google ads
Search

Everything you need to know about Computed Tomography (CT) & CT Scanning

June 2021 Imaging Pearls - Educational Tools | CT Scanning | CT Imaging | CT Scan Protocols - CTisus
Imaging Pearls ❯ June 2021

-- OR --

Adrenal

  • The Incidental Cystic Adrenal Mass: Differential Dx
    - Adrenal cyst
    - Adrenal hemorrhage (old)
    - Adrenal pheochromocytoma
    - Primary adrenal carcinoma
    - Adrenal metastases (melanoma, renal cell carcinoma)
  • The Incidental Cystic Adrenal Mass: Differential Dx
    - Adrenal cyst
    - Adrenal hemorrhage (old)
    - Adrenal adenoma
    - Adrenal pheochromocytoma
    - Primary adrenal carcinoma
    - Adrenal metastases (melanoma, renal cell carcinoma)
    - Uncommon benign tumors (i.e. ganglioneuroma, unusual myelolipoma)
  • The Incidental Cystic Adrenal Mass: Imaging Parameters
    - Lesion size
    - Lesion shape (round, oval or irregular shape)
    - Enhancement if any (especially peripheral)
    - Presence of calcification (peripheral or central)
    - Unilateral vs bilateral adrenal involvement
    - Extra-adrenal findings
    - Clinical history and presentation (i.e. hypertension, anti-coagulation therapy)
  • “Adrenal infections, although rare are important causes of adrenal insufficiency. Infection is the leading cause of adrenal insufficiency (Addison’s disease) in the developing world, with the most common agent Mycobacterium tuberculosis accounting for approximately 30% of reported cases. As with infections elsewhere in the body, adrenal infections are more common in the immunocompromised patient . Adrenal infections can be primary or secondary to systemic dissemination and adrenal involvement in systemic infection is reported in up to 80 percent of cases evaluated with autopsy.”
    CT and MR imaging of acute adrenal disorders  
    Amar Udare et al.
    Abdominal Radiology (2021) 46:290–302
  • “Early tuberculous adrenalitis is seen as bilateral adrenal enlargement with central non-enhancing areas due to necrosis with peripheral enhancement.  The imaging appearance of Histoplasmosis is indistinguishable from that of Tuberculosis and should be considered in the differential diagnosis in endemic areas, as adrenal insufficiency is seen in up to 50% of patients with disseminated histoplasmosis and is fatal if untreated. In chronic stages both tuberculosis and histoplasmosis are seen as atrophic adrenal glands with foci of calcification.”
    CT and MR imaging of acute adrenal disorders  
    Amar Udare et al.
    Abdominal Radiology (2021) 46:290–302
  • Adrenal Hemorrhage: Etiology
    - Trauma
    - Anticoagulant therapy
    - Stress related
    - Underlying tumor (benign and malignant)
  • “The imaging appearance of acute non-traumatic hemorrhage is similar to that of traumatic hemorrhage, typically a round to oval lesion appearing hyperdense on non-contrast enhanced CT images, hypointense on T1W and markedly hypointense on T2W images is observed. As with traumatic hemorrhages, hemorrhage gradually decreases in size and attenuation on CT and has a variable appearance on MRI depending on the stage of blood products, as described previously.Adrenal hemorrhage is often preceded by congestion which can be seen on CT as diffuse thickening of the gland with peri-adrenal fat stranding.”
    CT and MR imaging of acute adrenal disorders  
    Amar Udare et al.
    Abdominal Radiology (2021) 46:290–302
  • “Hemorrhage into an existing adrenal tumor can often mask the underlying lesion, especially in the acute stage and when there is no prior imaging available at time of first presentation. Intratumoral hemorrhage can either be spontaneous or secondary to trauma. Although rare, intratumoral adrenal hemorrhage is the fourth most common cause of spontaneous retroperitoneal hemorrhage after renal cell carcinoma, renal angiomyolipoma and renal artery aneurysm.”
    CT and MR imaging of acute adrenal disorders  
    Amar Udare et al.
    Abdominal Radiology (2021) 46:290–302
  • “The most common adrenal tumors associated with hemorrhage include pseudocyst, myelolipoma, adrenal hemangioma, pheochromocytoma, adrenocortical carcinomas, hemorrhagic adrenal metastases (most commonly from bronchogenic carcinoma and malignant melanoma) and rarely adrenal adenoma .Benign tumors more commonly hemorrhage compared to malignant tumors and pheochromocytoma is the most common benign tumor which may bleed.”
    CT and MR imaging of acute adrenal disorders  
    Amar Udare et al.
    Abdominal Radiology (2021) 46:290–302
  • “Adrenal infarction is a rare cause of adrenal insufficiency and can be hemorrhagic or non-hemorrhagic, the latter being less common. Most reports have been described in patients with primary antiphospholipid-antibody syndrome (PAPS) and less commonly in pregnancy, heparin induced thrombocytopenia, myelodysplastic syndrome and Crohn’s disease. Up to 36% of patients with PAPS present with adrenal insufficiency as the first manifestation of the disease.”
    CT and MR imaging of acute adrenal disorders  
    Amar Udare et al.
    Abdominal Radiology (2021) 46:290–302
  • “On CT, the infarcted adrenals are seen as enlarged hypodense glands with absent or poor contrast enhancement. Moschetta et al. described the capsular rim sign in 83% of patients with adrenal infarction, seen as diffusely enlarged hypodense gland with a thin rim of peripheral enhancement, likely due to residual perfusion of the adrenal capsular veins. On MRI, the infarcted adrenal glands have an edematous appearance with retroperitoneal edema, best seen as hyperintensity on fat saturated T2W images. A few recent case reports have described restricted diffusion in the infarcted adrenal glands.”
    CT and MR imaging of acute adrenal disorders  
    Amar Udare et al.
    Abdominal Radiology (2021) 46:290–302
  • “On CT, the infarcted adrenals are seen as enlarged hypodense glands with absent or poor contrast enhancement. Moschetta et al. described the capsular rim sign in 83% of patients with adrenal infarction, seen as diffusely enlarged hypodense gland with a thin rim of peripheral enhancement, likely due to residual perfusion of the adrenal capsular veins. On MRI, the infarcted adrenal glands have an edematous appearance with retroperitoneal edema, best seen as hyperintensity on fat saturated T2W images. A few recent case reports have described restricted diffusion in the infarcted adrenal glands.”
    CT and MR imaging of acute adrenal disorders  
    Amar Udare et al.
    Abdominal Radiology (2021) 46:290–302
Chest

  • “Thymic masses are comprised of hyperplasia, cysts, thymic epithelial tumors (TETs), lymphomas, malignant germ cell tumors or metastatic cancers and so on. True thymic hyperplasia is usually regarded as a rebound phenomenon and characterized by an increase in mass of the gland after a stressor, such as chemotherapy, radiation, steroid treatment, burns or surgery. Thymic cysts are relatively uncommon lesions that can be found at any age and can be congenital or acquired. Although TETs are rare neoplasms as to the whole tumors, they are the most common mediastinal tumors in adults, including thymomas and thymic carcinomas.”
    “Comparison between CT and MRI in the Diagnostic Accuracy of Thymic Masses.”  
    Li, Hao-Ran et al.  
    Journal of Cancer vol. 10,14 3208-3213. 
  • “True thymic hyperplasia is usually regarded as a rebound phenomenon and characterized by an increase in mass of the gland after a stressor, such as chemotherapy, radiation, steroid treatment, burns or surgery.”
    “Comparison between CT and MRI in the Diagnostic Accuracy of Thymic Masses.”  
    Li, Hao-Ran et al.  
    Journal of Cancer vol. 10,14 3208-3213. 
  • Thymic Hyperplasia: Etiology
    - Graves disease
    - Response following chemotherapy
    - Myasthenia gravis
  • Masses of Thymic Origin
    - Benign
    --- Thymic hyperplasia
    --- Thymic cyst
    --- Thymolipoma
    --- Thymoma (Masaoka-Koga stage I/II)
    - Malignant
    --- Thymoma (Masaoka-Koga stage III/IV)
    --- Thymic carcinoma
    --- Thymic lymphoma
    --- Thymic carcinoid
    - Rare lesions
    --- Metastatic disease
    --- Langerhans cell histiocytosis
    --- Thymic germ cell tumour
    --- Follicular dendritic cell sarcoma
  • “Two distinct histologic types of thymic hyperplasia exist:true thymic hyperplasia and lymphoid follicular hyperplasia. In true thymic hyperplasia, the gland is enlarged(ie, increased mass of tissue) with preserved microscopic and histologic architecture. In lymphoid follicular hyperplasia,enlarged lymphoid germinal centers account for the increased size of the gland. These 2 entities are indistinguishable from one another at imaging.”
    A Tour of the Thymus: A Review of Thymic Lesions With Radiologic and Pathologic Correlation
    Goldstein AJ et al.
    Canadian Association of Radiologists Journal, Volume 66, Issue 1,2015,Pages 5-15
  • "True thymic hyperplasia is usually seen as a rebound phenomenon, characterized by an increase in mass of the gland after a stressor, such as chemotherapy, radiation, steroid treatment, burns, or surgery. Lymphoid follicular hyperplasia is associated with numerous chronic inflammatory and autoimmune disorders, including myasthenia gravis, Graves disease, systemic lupus erythematosus, rheumatoid arthritis, scleroderma, and other autoimmune conditions.”
    A Tour of the Thymus: A Review of Thymic Lesions With Radiologic and Pathologic Correlation
    Goldstein AJ et al.
    Canadian Association of Radiologists Journal, Volume 66, Issue 1,2015,Pages 5-15
  • "Although the 2 types of thymic hyperplasia are impossible to differentiate at imaging, thymic hyperplasia can often be differentiated from neoplasm on the basis of key imaging findings. Thymic hyperplasia is usually manifested by diffuse, symmetric thymic enlargement, a smooth contour, interspersed fat and soft-tissue elements, normal vessels, and preserved adjacent fat planes. Alternatively, a neoplasm may demonstrate a focal mass, a nodular contour, heterogeneity (ie, hemorrhage or necrosis), or calcifications.”
    A Tour of the Thymus: A Review of Thymic Lesions With Radiologic and Pathologic Correlation
    Goldstein AJ et al.
    Canadian Association of Radiologists Journal, Volume 66, Issue 1,2015,Pages 5-15
  • "Thymolipoma is a rare, benign, predominantly fatty mass with interspersed fibrous septae and normal thymic tissue. Due to their pliability, thymolipomas can become very large and have been reported to occupy almost the entire hemithorax. On imaging, they appear as large, fatty masses with scattered soft-tissue components, and can mimic mediastinal or epicardial lipomatosis. On histologic examination, they are characterized by mature adipose tissue with non-neoplastic thymic epithelial cells and fibrous bands.”
    A Tour of the Thymus: A Review of Thymic Lesions With Radiologic and Pathologic Correlation
    Goldstein AJ et al.
    Canadian Association of Radiologists Journal, Volume 66, Issue 1,2015,Pages 5-15
  • "Thymoma is the most common anterior mediastinal mass in adults. These tumours are often asymptomatic and incidentally discovered but may present with cough, hoarseness, dysphagia, chest pain, or symptoms related to vascular compression. CT imaging usually reveals a homogenous soft-tissue mass with sharp borders and a lobulated, round, or oval shape. Occasionally, calcifications or low-density components that represent necrosis can be seen (especially in large tumours) . Thymoma is classically associated with myasthenia gravis, and approximately 30%–50% of patients with thymoma have myasthenia gravis; alternatively, only 10%–20% of patients with myasthenia gravis have an underlying thymoma.”
    A Tour of the Thymus: A Review of Thymic Lesions With Radiologic and Pathologic Correlation
    Goldstein AJ et al.
    Canadian Association of Radiologists Journal, Volume 66, Issue 1,2015,Pages 5-15
Colon

  • “Checkpoint inhibitor (CPI) immunotherapy has transformed the treatment of multiple cancers over the past decade, leading to durable remissions, but also to severe inflammatory toxicities. These toxicities, termed immune-related adverse events (irAEs), can affect any organ system in the body, but commonly induce inflammation in barrier organs. Gastrointestinal (GI) and hepatic irAEs are among the most frequent and most severe from contemporary immunotherapies, with inflammation in the colon and or small intestines (entero)colitis as the single most common GI irAE.”
    Gastrointestinal and Hepatic Complications of Immunotherapy: Current Management and Future Perspectives.
    Dougan M.  
    Curr Gastroenterol Rep. 2020 Mar 17;22(4):15
  • "Although most patients who develop enterocolitis recover without long-term GI sequelae, enterocolitis is still an important reason for treatment discontinuation, which, in patients with metastatic cancer, can be a life-threatening outcome. At present, we have almost no prospective, randomized data regarding the management of CPI enterocolitis, and current management algorithms are based on expert opinion and small retrospective studies with a high likelihood of bias. Retrospective studies have defined colonic ulceration as a predictor of colitis responsiveness to corticosteroids, and have defined microscopic colitis as a subtype of CPI enterocolitis with a distinct treatment response.”
    Gastrointestinal and Hepatic Complications of Immunotherapy: Current Management and Future Perspectives.  
    Dougan M.  
    Curr Gastroenterol Rep. 2020 Mar 17;22(4):15
  • Background and aims: Immune checkpoint inhibitor (ICI) enterocolitis is a common immune-related adverse event and can be fatal, especially when not diagnosed and treated promptly. The current gold standard for diagnosis is endoscopy with biopsy, but CT scan is a possible alternative. The primary objective of this study is to identify the diagnostic performance of CT in the evaluation of ICI enterocolitis.
    Results: Of the 4474 patients screened, 138 met inclusion criteria. Most common tumor types were melanoma (37%) and lung cancer (19%). Seventy-four per cent were treated with antiprogrammed cell death (PD-1)/PD-L1 therapy. Thirty-nine per cent had signs of enterocolitis on CT scan and 58% had biopsy-proven ICI enterocolitis. Sensitivity and specificity of CT were 50% and 74%, respectively. PPV was 73% and NPV was 52%. Of those with confirmed ICI enterocolitis, 70% had grade 3 or higher symptoms, 91% received steroids and 40% received infliximab.
    Conclusion: The performance of CT scan for diagnosis of ICI enterocolitis is moderate to poor and does not replace endoscopy with biopsy.
    Diagnostic utility of CT for suspected immune checkpoint inhibitor enterocolitis.  
    Durbin SM et al.
    J Immunother Cancer. 2020 Oct;8(2):e001329.
  • “Immune-related enterocolitis (irEC) is the most common serious complication from checkpoint inhibitors (CPIs). The current front-line treatment for irEC, high-dose corticosteroids (CS), have significant side effects and prolonged therapy may reduce CPI-anti-tumor activity. Early addition of TNF-α inhibitors such as infliximab (IFX) may expedite symptom resolution and shorten CS duration.”  
    Infliximab associated with faster symptom resolution compared with corticosteroids alone for the management of immune-related enterocolitis.  
    Johnson DH et al.
    J Immunother Cancer. 2018 Oct 11;6(1):103.
  • “Checkpoint inhibitors (CPIs) have improved overall survival (OS) for patients with various malignancies. Currently available CPIs target the cytotoxic T-lymphocyte antigen 4 (anti–CTLA-4 agents include ipilimumab and tremelimumab), programmed death 1 (anti–PD-1 agents include pembrolizumab and nivolumab), and programmed death ligand 1 (anti–PD-L1 agents include atezolizumab, avelumab, and durvalumab). Newer agents continue to emerge, expanding the therapeutic applications of CPIs in cancer management. However, CPIs can cause severe immune-related adverse events, among which immune-related enterocolitis (irEC) is the most common serious complication.”
    Infliximab associated with faster symptom resolution compared with corticosteroids alone for the management of immune-related enterocolitis.  
    Johnson DH et al.
    J Immunother Cancer. 2018 Oct 11;6(1):103.
  • “Cronkhite-Canada syndrome (CCS) is a rare nonhereditary disease characterized by diffuse gastrointestinal hyperplastic polypoid lesions and ectodermal symptoms such as pigmentation, alopecia and onychatrophia. Since Cronkhite and Canada first reported about this syndrome in 1955, more than 500 cases have been reported worldwide, the majority of which were from Japan. The etiology of CCS is currently unknown, and the association between gastrointestinal polyposis and ectodermal symptoms is undetermined.”
    “Cronkhite-Canada Syndrome Successfully Treated by Corticosteroids before Presenting Typical Ectodermal Symptoms.”  
    Murata, Kazumoto et al.  
    Case reports in gastroenterology vol. 14,3 561-569. 30 Oct. 2020
  • “Cronkhite-Canada syndrome (CCS) is a noninherited condition associated with high morbidity and characterized by gastrointestinal hamartomatous polyposis, alopecia, onychodystrophy, hyperpigmentation, and diarrhea.”
    Cronkhite-Canada syndrome: an acquired condition of gastrointestinal polyposis and dermatologic abnormalities.
    Sweetser S, Boardman LA.
    Gastroenterol Hepatol (N Y). 2012 Mar;8(3):201-3. 
  • “Polyps in CCS patients can develop throughout the gastrointestinal tract (except for the esophagus) and are non-neoplastic hamartomas. Nevertheless, there is concern that CCS polyps may possess malignant potential, as evidenced by the dysplastic intestinal changes noted by Seshadri and coworkers and by reports of gastric, colon, and rectal cancers in patients with CCS.”
    Cronkhite-Canada syndrome: an acquired condition of gastrointestinal polyposis and dermatologic abnormalities.
    Sweetser S, Boardman LA.
    Gastroenterol Hepatol (N Y). 2012 Mar;8(3):201-3. 
  • “The diagnosis of CCS should be considered in patients with gastrointestinal hamartomatous polyps, diarrhea, and the dermatologic triad of alopecia, hyperpigmentation, and onychodystro-phy. Malignant transformation of CCS polyps may occur, and the risk of colorectal cancer may warrant aggressive screening in CCS patients. Immunosuppression with corticosteroids or long-term azathioprine therapy may eradicate or lessen manifestations of CCS.”
    Cronkhite-Canada syndrome: an acquired condition of gastrointestinal polyposis and dermatologic abnormalities.
    Sweetser S, Boardman LA.
    Gastroenterol Hepatol (N Y). 2012 Mar;8(3):201-3. 
Deep Learning

  • “Artificial intelligence is poised to revolutionize medical image. It takes advantage of the high-dimensional quantitative features present in medical images that may not be fully appreciated by humans. Artificial intelligence has the potential to facilitate automatic organ segmentation, disease detection and characterization, and prediction of disease recurrence. This article reviews the current status of artificial intelligence in liver imaging and reviews the opportunities and challenges in clinical implementation.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "Artificial intelligence is commonly performed with supervised learning because of the complexity of medical image analysis. It is provided with annotated “ground truth,” which is used as feedback to improve the algorithm. The degree of data annotation in a detection or segmentation problem can range from labeling subjects as normal versus abnormal, creating an approximate bounding box in the region of the abnormality, to detailed slice-by-slice segmentation of the specific abnormality. Artificial intelligence algorithms depend on large data sets with high-quality images and annotations for training as well as validation, and their performance increases logarithmically with increased training data.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • “Radiomics converts imaging data into high-dimensional quanitative features, which can be classified into first order, shape, and texture features. First-order features are derived from histogram distribution of individual voxel signal intensities, which can provide statistics on central tendency, variance, range, and shape of the distribution. Shape features are generated from the 3-dimensional surface mask of the region of interest and can provide measures such as volume, surface area, and sphericity. Texture features, also referred to as second order features, quantify the correlation of signal intensities with respect to surrounding voxels in 3 dimensions. In addition, different types of filters (eg, wavelets, Laplacian of Gaussian) are often applied to the original imaging volume to generate the filtered imaging volume before feature extraction. This process typically generates hundreds of features, and redundant features are eliminated through dimension reduction. Machine learning algorithms, such as random forest and support vector machine, are frequently used to analyze the most relevant features.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • “Deep learning-based algorithms have outperformed traditional semiautomatic interactive methods25 and can be significantly faster than manual segmentation.26 In most cases, the deep network is trained to segment the liver in a specific modality (eg, CT or MRI). Wang et al16 trained an algorithm on 1 modality (eg, unenhanced MRI) and was able to adapt it to other modalities (eg, contrast-enhanced CT or MRI) via transfer learning. This type of modality-independent segmentation algorithm may broaden the scope of potential clinical applications.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "Because of black-box nature of the AI models, it can be difficult for the radiologists and clinicians to understand the rationale behind the AI output. This can especially problematic if there is discrepancy between the radiologists' subjective assessment and the AI output. Wang et al sought to make deep learning classification results more “understandable” by training a convolutional neural network with specific training image examples of radiologic features relevant in liver lesion classification. They generated feature maps that ranked the most relevant features used in the lesion classification task. This type of supportive evidence may increase radiologists' confidence in the AI classification.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "Radiomics models have been used to predict recurrence and survival after curative resection, ablation or liver transplantatio8 in patients with HCC. Radiomics models have been able to predict disease recurrence with higher accuracy than traditional clinical models, with the C-index (concordance index measuring goodness of fit for binary outcomes) ranging from 0.47 to 0.82 for radiomics models versus 0.56 to 0.78 for clinical models. The addition of radiomics features to clinical models generally helps to improve risk stratification. It makes intuitive sense that the best prognostic models would incorporate both tumor features (captured by qualitative imaging features and radiomics features) and clinical features that consider background liver disease, patient comorbidities, and performance status.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "Legal ramifications also need to be considered in the clinical implementation of AI. Just like humans, AI is not perfect. The IBM Watson Health's cancer AI algorithm (known as Watson for Oncology) was trained on a small number of synthetic cases with limited input from oncologists. As a result, many output treatment recommendations were erroneous and potentially harmful.93 If a clinician makes a mistake based on flawed AI decision support, who is legally responsible? The black-box nature of many AI algorithms also complicates efforts to tease out the exact cause of any errors. Medical AI systems are too new to have been involved in malpractice lawsuits, and it remains to be seen where the responsibilities lie.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "In this early exploratory phase of applying AI to liver imaging, studies have shown that AI can achieve impressive performance in disease detection, classification, and prognostication under highly controlled experimental settings. These results should be validated in multicenter trials with stringent postmarketing monitoring to ensure safety and efficacy across different practice environments. Artificial intelligence algorithms should be combined to perform comprehensive organ-specific or more general abdominal abnormality detection to be more clinically relevant.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351

  • Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman
    J Comput Assist Tomogr 2021;45: 343–351

  • Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman 
    J Comput Assist Tomogr 2021;45: 343–351

  • Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman 
    J Comput Assist Tomogr 2021;45: 343–351
Kidney

  • “Renal cell carcinoma (RCC) represents above 3 % of all cancers, with the highest incidence occurring in Western countries. At diagnosis, above 25 % of patients with RCC present an advanced disease, including locally invasive or metastatic cancer. The mean survival time of patient with metastatic RCC is approximately 13 months. The most common metastatic RCC sites are the lung and bone (up to 60 % and 40 % of patients with metastases). However, unusual sites of metastasis are characteristics of RCC and any organ site can be involved, including the thyroid, pancreas, skeletal muscle and skin.”
    Are gastric metastases of renal cell carcinoma really rare? A case report and systematic review of the literature
    Thomas Prudhomme et al.
    International Journal of Surgery Case Reports, Volume 82,2021
  • "At RCC gastric metastasis diagnosis, 73 % of the patients presented multiple metastatic sites, mainly lungs and bones. The median patients age (IQR) was 66.0 (60.0–69.0) years, of whom 74 % were men. The median time (IQR) between the diagnosis of RCC and metachronous gastric metastasis was 5.0 (2.0–9.5) years. 3 patients presented RCC with synchronous gastric metastasis. 35 % of the patients had a surgical treatment, 16 % an endoscopic treatment, 23 % a systemic therapy and 26 % a palliative treatment. Endoscopic treatment was mucosal and submucosal resection without positive surgical margins. Median patient survival (IQR), after treatment, was 6 months.”
    Are gastric metastases of renal cell carcinoma really rare? A case report and systematic review of the literature
    Thomas Prudhomme et al.
    International Journal of Surgery Case Reports, Volume 82,2021
  • "Renal cell carcinoma is the most common solid lesion within the kidney and accounts approximately 90 % of all kidney malignancies. It comprises different RCC subtypes with specific histopathological characteristics. Clear cell RCC is the most common histopathological entities of RCC and clear cell RCC has worse prognosis compared to other histopathological entities, even after stratification for stage and grade. Indeed, clear cell RCC has an abundant blood supply and can metastasize to several organs. Metastasis routes include hematogenous, lymphogenous, renal capsule, renal pelvis and ureteric routes, which explains the wide variety of organs that can be RCC metastatic sites.”
    Are gastric metastases of renal cell carcinoma really rare? A case report and systematic review of the literature
    Thomas Prudhomme et al.
    International Journal of Surgery Case Reports, Volume 82,2021
Liver

  • “Artificial intelligence is poised to revolutionize medical image. It takes advantage of the high-dimensional quantitative features present in medical images that may not be fully appreciated by humans. Artificial intelligence has the potential to facilitate automatic organ segmentation, disease detection and characterization, and prediction of disease recurrence. This article reviews the current status of artificial intelligence in liver imaging and reviews the opportunities and challenges in clinical implementation.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "Artificial intelligence is commonly performed with supervised learning because of the complexity of medical image analysis. It is provided with annotated “ground truth,” which is used as feedback to improve the algorithm. The degree of data annotation in a detection or segmentation problem can range from labeling subjects as normal versus abnormal, creating an approximate bounding box in the region of the abnormality, to detailed slice-by-slice segmentation of the specific abnormality. Artificial intelligence algorithms depend on large data sets with high-quality images and annotations for training as well as validation, and their performance increases logarithmically with increased training data.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • “Radiomics converts imaging data into high-dimensional quanitative features, which can be classified into first order, shape, and texture features. First-order features are derived from histogram distribution of individual voxel signal intensities, which can provide statistics on central tendency, variance, range, and shape of the distribution. Shape features are generated from the 3-dimensional surface mask of the region of interest and can provide measures such as volume, surface area, and sphericity. Texture features, also referred to as second order features, quantify the correlation of signal intensities with respect to surrounding voxels in 3 dimensions. In addition, different types of filters (eg, wavelets, Laplacian of Gaussian) are often applied to the original imaging volume to generate the filtered imaging volume before feature extraction. This process typically generates hundreds of features, and redundant features are eliminated through dimension reduction. Machine learning algorithms, such as random forest and support vector machine, are frequently used to analyze the most relevant features.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • “Deep learning-based algorithms have outperformed traditional semiautomatic interactive methods25 and can be significantly faster than manual segmentation.26 In most cases, the deep network is trained to segment the liver in a specific modality (eg, CT or MRI). Wang et al16 trained an algorithm on 1 modality (eg, unenhanced MRI) and was able to adapt it to other modalities (eg, contrast-enhanced CT or MRI) via transfer learning. This type of modality-independent segmentation algorithm may broaden the scope of potential clinical applications.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "Because of black-box nature of the AI models, it can be difficult for the radiologists and clinicians to understand the rationale behind the AI output. This can especially problematic if there is discrepancy between the radiologists' subjective assessment and the AI output. Wang et al sought to make deep learning classification results more “understandable” by training a convolutional neural network with specific training image examples of radiologic features relevant in liver lesion classification. They generated feature maps that ranked the most relevant features used in the lesion classification task. This type of supportive evidence may increase radiologists' confidence in the AI classification.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "Radiomics models have been used to predict recurrence and survival after curative resection, ablation or liver transplantatio8 in patients with HCC. Radiomics models have been able to predict disease recurrence with higher accuracy than traditional clinical models, with the C-index (concordance index measuring goodness of fit for binary outcomes) ranging from 0.47 to 0.82 for radiomics models versus 0.56 to 0.78 for clinical models. The addition of radiomics features to clinical models generally helps to improve risk stratification. It makes intuitive sense that the best prognostic models would incorporate both tumor features (captured by qualitative imaging features and radiomics features) and clinical features that consider background liver disease, patient comorbidities, and performance status.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "Legal ramifications also need to be considered in the clinical implementation of AI. Just like humans, AI is not perfect. The IBM Watson Health's cancer AI algorithm (known as Watson for Oncology) was trained on a small number of synthetic cases with limited input from oncologists. As a result, many output treatment recommendations were erroneous and potentially harmful.93 If a clinician makes a mistake based on flawed AI decision support, who is legally responsible? The black-box nature of many AI algorithms also complicates efforts to tease out the exact cause of any errors. Medical AI systems are too new to have been involved in malpractice lawsuits, and it remains to be seen where the responsibilities lie.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351
  • "In this early exploratory phase of applying AI to liver imaging, studies have shown that AI can achieve impressive performance in disease detection, classification, and prognostication under highly controlled experimental settings. These results should be validated in multicenter trials with stringent postmarketing monitoring to ensure safety and efficacy across different practice environments. Artificial intelligence algorithms should be combined to perform comprehensive organ-specific or more general abdominal abnormality detection to be more clinically relevant.”
    Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman  
    J Comput Assist Tomogr 2021;45: 343–351

  • Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman
    J Comput Assist Tomogr 2021;45: 343–351

  • Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman 
    J Comput Assist Tomogr 2021;45: 343–351

  • Current Status of Radiomics and Deep Learning in Liver Imaging  
    Linda C. Chu, Seyoun Park, Satomi Kawamoto, Alan L. Yuille, Ralph H. Hruban, and Elliot K. Fishman 
    J Comput Assist Tomogr 2021;45: 343–351
OB GYN

  • “Postpartum hemorrhage continues to be the leading preventable cause of maternal illness and death globally. Worldwide, postpartum hemorrhage accounts for 8% of maternal deaths in developed regions of the world and 20% of maternal deaths in developing regions. The United States has one of the highest maternal mortality rates among developed countries, with approximately 11% of all maternal deaths associated with postpartum hemorrhage.3 During the period from 1993 through 2014, the rate of postpartum hemorrhage (which was defined as blood loss >1000 ml after vaginal or cesarean delivery) requiring a blood transfusion4 increased from approximately 8 cases per 10,000 deliveries to 40 per 10,000 deliveries in the United States.”  
    Postpartum Hemorrhage  
    Jessica L. Bienstock et al.
    N Engl J Med 2021;384:1635-45
  • “The traditional definition of postpartum hemorrhage is blood loss of more than 500 ml after a vaginal delivery or more than 1000 ml after a cesarean delivery. More recently, postpartum hemorrhage has been redefined as a cumulative blood loss of 1000 ml or more or blood loss associated with signs or symptoms of hypovolemia, irrespective of the route of delivery. Typical clinical signs and symptoms of hypovolemia (e.g., hypotension and tachycardia) due to postpartum hemorrhage may not appear until blood loss exceeds 25% of total blood volume (>1500 ml during late pregnancy).”
    Postpartum Hemorrhage  
    Jessica L. Bienstock et al.
    N Engl J Med 2021;384:1635-45
  • “Postpartum hemorrhage is considered to be primary when it occurs within the first 24 hours after delivery and secondary when it occurs between 24 hours and up to 12 weeks after delivery. The causes of postpartum hemorrhage can be summarized by the four “T’s”: tone (uterine atony), trauma (lacerations or uterine rupture),  tissue (retained placenta or clots), and thrombin (clotting-factor deficiency).10 The most common cause is uterine atony (accounting for approximately 70% of cases), followed by obstetrical lacerations (approximately 20%), retained placental tissue (approximately 10%), and clotting-factor deficiencies (<1%).”
    Postpartum Hemorrhage  
    Jessica L. Bienstock et al.
    N Engl J Med 2021;384:1635-45
  • "The causes of postpartum hemorrhage can be summarized by the four “T’s”: tone (uterine atony), trauma (lacerations or uterine rupture), issue (retained placenta or clots), and thrombin (clotting-factor deficiency). The most common cause is uterine atony (accounting for approxi- mately 70% of cases), followed by obstetrical lac- erations (approximately 20%), retained placental tissue (approximately 10%), and clotting-factor deficiencies (<1%).”
    Postpartum Hemorrhage  
    Jessica L. Bienstock et al.
    N Engl J Med 2021;384:1635-45
  • "Other risk factors for postpartum hemorrhage are closely linked to the type of hemorrhage that develops. For example, obstetrical lacerations can be caused by operative vaginal delivery, precipitous delivery, or episiotomy, whereas retained placental tissue can be caused by placenta accreta spectrum (PAS; a spectrum of abnormal placentation disorders, including placenta accreta, placenta increta, and placenta percreta), which is associ- ated with prior uterine surgery. Retained placental tissue can also be the result of incomplete delivery of the placental tissue and membranes. Maternal coagulopathy that leads to postpartum hemorrhage can be a complication of severe pre- eclampsia and eclampsia, HELLP (hemolysis, elevated liver-enzyme level, and low platelet count) syndrome, intrauterine fetal death, placental abruption, or a coagulation disorder that is acquired (e.g., amniotic fluid embolism) or inherited.”
    Postpartum Hemorrhage  
    Jessica L. Bienstock et al.
    N Engl J Med 2021;384:1635-45
  • "Postpartum hemorrhage remains a clinically significant cause of maternal complications and death; worldwide, one woman dies from postpartum hemorrhage every 7 minutes. There- fore, prompt identification of patients who are at risk for postpartum hemorrhage, routine ac-  tive management of the third stage of labor, expeditious assessment of blood loss, appropriate patient monitoring, and management of postpartum hemorrhage are important.”
    Postpartum Hemorrhage  
    Jessica L. Bienstock et al.
    N Engl J Med 2021;384:1635-45
Pancreas

  • “In conclusion, pancreatic cystosis is a rare manifestation of CF and is thought to be caused by ductal dilatation resulting from ductal protein precipitation. The diagnosis can easily be made in the appropriate clinical setting by means of sonography, CT, or MRI; however, sonography should be the technique of choice for initial and follow-up evaluation of patients with these findings. Although CT and MRI allow an adequate assessment of the structure and content of the cysts and a more panoramic view of the pancreas than sonography, they do not provide any relevant additional information to the data provided by sonography.”  
    Pancreatic Cystosis in Children and Young Adults with Cystic Fibrosis: Sonographic, CT, and MRI Findings  
    Teresa Berrocal et al.
    AJR 2005;184:1305–1309 
  • "Pancreatic involvement can result in exo-  crine or endocrine insufficiency. The spectrum of pancreatic appearances has been described as follows: complete replacement of the pancreas by fibrofatty tissue, with enlargement of the pancreas corresponding to lipomatous pseudohypertrophy; partial replacement of the pancreas by fibrofatty tissue; complete atrophy of the pancreas without fatty replacement; diffuse pancreatic fibrosis; and cystic transformation of the pancreas. Calcifications may also be found.”
    Pancreatic Cystosis in Children and Young Adults with Cystic Fibrosis: Sonographic, CT, and MRI Findings  
    Teresa Berrocal et al.
    AJR 2005;184:1305–1309 
  •  “Cyst are a relatively common feature in the CF-affected pancreas, but their size does not usually exceed a few millimeters. Macroscopic cysts measuring more than 1 cm are a rare condition. Macrocysts of different sizes distributed throughout the gland represent an extremely unusual form of pancreatic involvement in CF that has been described in only a few patients and is known as pancreatic cystosis.”
    Pancreatic Cystosis in Children and Young Adults with Cystic Fibrosis: Sonographic, CT, and MRI Findings  
    Teresa Berrocal et al.
    AJR 2005;184:1305–1309 
  • "The imaging features of pancreatic macro- cysts seen in our patients are similar to those of uncomplicated pancreatic cysts from any other cause. No parietal cyst calcifications were present in our series. A parietal calcification in one cyst and evidence of hemorrhage in another cyst during an observation period in one CF patient with pancreatic cystosis have been reported using sonography and CT.”
    Pancreatic Cystosis in Children and Young Adults with Cystic Fibrosis: Sonographic, CT, and MRI Findings  
    Teresa Berrocal et al.
    AJR 2005;184:1305–1309 
  • “SPNs are usually large, well-demarcated lesions of the pancreas with both cystic and solid components. A review of more than 2700 patients suggested a mean tumour diameter of 8.6 cm, while smaller reviews point at a tumour size of 6 cm. Similarly, in our cohort, we found lesions of variable size ranging from 1.5 to 15.3 cm with a median size of 5 cm. The sheer size of these lesions makes non-specific abdominal pain the most common presenting symptom at the time of diagnosis [8], which was also reiterated by our cohort. Other presenting symptoms may include non-specific abdominal symptoms and jaundice. As many as 30% may be asymptomatic and are diagnosed incidentally, such as following screening for unrelated reasons or deranged blood tests like in our experience.”
    Solid Pseudopapillary Neoplasms of the Pancreas: a Single‐Center Experience
    Moustafa Allam et al.  
    Journal of Gastrointestinal Cancer  2021 (in press)
  • "As many as 30% may be asymptomatic and are diagnosed incidentally, such as following screening for unrelated reason or deranged blood tests like in our experience. Moreover, SPNs in our cohort, in concordance with what is reported in the literature, appear to be most commonly localized to either the tail or the head of the pancreas, with only a small minority found in the pancreatic body and tail- or head-body junction.”
    Solid Pseudopapillary Neoplasms of the Pancreas: a Single‐Center Experience
    Moustafa Allam et al.  
    Journal of Gastrointestinal Cancer  2021 (in press)
  • "Cross-sectional imaging is a widely accepted pre- operative diagnostic modality. On CT, SPNs usually appear as a large mass of mixed solid and cystic appearance originating in the pancreas. According to the extent of degenerative changes, their appearance may range from almost completely solid to almost completely cystic. Cystic areas are most commonly found in the centre, while solid components tend to predominate in the periphery. The attenuation of the cystic components can vary from density similar to water to dense haemorrhagic debris . Areas of calcification are also frequent, and these calcifications may be most prominent around the rim of the lesion but may also be found centrally.”
    Solid Pseudopapillary Neoplasms of the Pancreas: a Single‐Center Experience
    Moustafa Allam et al.  
    Journal of Gastrointestinal Cancer  2021 (in press)
  • "SPNs have an uncertain malignant potential, and as such, in 1996, the WHO classified them as borderline tumours. Although mostly benign, some SPNs have been shown to metastasize preferentially to the liver, but also to the lungs and peritoneum in most aggressive cases. As the vast majority of SPNs resected are benign, the overall survival is good; nevertheless, there is an increasing body of evidence recognizing the malignant potential of these lesions. Studies have identified several predictors of malignancy including large tumour size, focal discontinuity of SPN capsule, Ki-67 proliferative index, and exophytic growth pattern. Current literature has shown a recurrence rate after resection of around 10–15%.”  
    Solid Pseudopapillary Neoplasms of the Pancreas: a Single‐Center Experience
    Moustafa Allam et al.  
    Journal of Gastrointestinal Cancer  2021 (in press)
  • Background: Contrast-enhanced CT performed for pancreatic ductal adenocarcinoma (PDAC) detection traditionally uses a dual-phase (pan-  creatic and portal venous) protocol. However, PDAC may exhibit isoattenuation in these phases, hindering detection.  
    Objective: To assess the impact on diagnostic performance in detection of small PDAC of adding a delayed phase to dual-phase contrast-enhanced CT.  
    Conclusion: Addition of delayed phase to pancreatic and portal venous phase CT increases sensitivity for small PDAC without loss of specificity, partly related to delayed phase hyperattenuation of some small PDACs showing pancreatic phase isoattenuation.  
    Clinical Impact: Addition of delayed phase may facilitate earlier PDAC detection and thus improved prognosis.
    Adding Delayed Phase Images to Dual-Phase Contrast-Enhanced CT Increases Sensitivity for Small Pancreatic Ductal Adenocarcinoma  
    Yoshihiko Fukukura et al.
    AJR 2021 (in press)
  • “In this retrospective study, we assessed the benefit of adding delayed phase images to a dual-phase contrast-enhanced CT protocol for the detection of small PDACs. Triple-phase images yielded significantly higher diagnostic accuracy and sensitivity than dual-phase images. The detection of PDAC when small increases the chance of curative surgery. Therefore, the addition of delayed phase imaging may ultimately improve the prognosis of patients with PDAC.”
    Adding Delayed Phase Images to Dual-Phase Contrast-Enhanced CT Increases Sensitivity for Small Pancreatic Ductal Adenocarcinoma  
    Yoshihiko Fukukura et al.
    AJR 2021 (in press)
  • "In conclusion, this study showed that triple-phase contrast-enhanced CT resulted in increased sensitivity and accuracy, without change in specificity, for the detection of small PDAC compared with dual-phase contrast-enhanced CT. This benefit in part related to hyperattenuation in the delayed phase of some small PDACs showing isoattenuation in the pancreatic phase. This change in pancreas CT protocols merits further consideration to potentially achieve earlier detection and thus improved PDAC prognosis.”
    Adding Delayed Phase Images to Dual-Phase Contrast-Enhanced CT Increases Sensitivity for Small Pancreatic Ductal Adenocarcinoma  
    Yoshihiko Fukukura et al.
    AJR 2021 (in press)
  • “The incidence of pancreatic neuroendocrine tumors (PNETs) has risen more than 6-fold over the last several decades, likely because of widespread use of advanced imaging studies for abdominal complaints. A subject of ongoing controversy is how to best manage small (<2 cm), incidentally discovered PNETs. Although most PNETs behave in an indolent fashion, some lesions will manifest more aggressive behavior. Surgical proce- dures play a pivotal role in the management of these tumors, as they represent the only curative treatment. Although most surgeons would advocate for resection of all functional PNETs (those causing a syndrome), recommendations to resect or observe asymptomatic or nonfunctional (NF) PNETs 2 cm or smaller vary based on data from different studies. This Viewpoint highlights the issues surrounding management strategies for patients with small NF-PNETs.”  
    Surgery vs Observation for Patients With Small Pancreatic Neuroendocrine Tumors  
    Aziz H, Howe JR, Pawlik TM
    JAMA Surgery May 2021 Volume 156, Number 5 
  • "The European Neuroendocrine Tumor Society and the National Comprehensive Cancer Network guidelines suggest that observation is a reasonable option for pa- tients with PNETs 2 cm or smaller. The North American Neuroendocrine Tumor Society guidelines state that ob- servation is appropriate for NF-PNETs smaller than 1 cm, but management of 1- to 2-cm lesions should be individualized based on age, comorbidities, growth, grade, extent of the surgical procedure needed, and patient preference.”
    Surgery vs Observation for Patients With Small Pancreatic Neuroendocrine Tumors  
    Aziz H, Howe JR, Pawlik TM
    JAMA Surgery May 2021 Volume 156, Number 5 
  • “Dong et al analyzed 989 patients who underwent curative-intent resection for NF-PNETs. Of 328 patients with tumors 2 cm or smaller who underwent resection and nodal dissection, 12.8% had lymph node metastasis, which conferred a 3-fold increased risk of tumor recurrence. Of note, patients with tumors measuring 1.5 to 2 cm had a significantly higher incidence of lymph node metastasis (17.9% vs 8.7%), higher Ki-67, and a greater risk of recurrence (8.0% vs 4.5%) compared with patients with PNETs 1.5 cm or smaller. Therefore, the authors suggested that patients with NF-PNETs measuring 1.5 to 2 cm should be strongly considered for surgical resection.”  
    Surgery vs Observation for Patients With Small Pancreatic Neuroendocrine Tumors  
    Aziz H, Howe JR, Pawlik TM
    JAMA Surgery May 2021 Volume 156, Number 5 
  • “Observation may also be preferred because pancreatic resec- tion continues to be associated with a risk of substantial morbidity as well as the potential for exocrine and endocrine insufficiency. A common cause of postoperative morbidity is postoperative pancreatic fistula, and severe postoperative complications occurred in 30% to 45% of patients who underwent surgery for small PNETs.6 Although mortality has improved over time for pancreatic resection, 30-day mortality in national databases still ranges from 4% to 8%. With these complication and mortality rates in mind, and because patients under surveillance rarely die of disease or develop distant metastasis, an initial approach of observation appears to be a safe option for many patients with NF-PNETS 2 cm or smaller.”  
    Surgery vs Observation for Patients With Small Pancreatic Neuroendocrine Tumors  
    Aziz H, Howe JR, Pawlik TM
    JAMA Surgery May 2021 Volume 156, Number 5 
  • “For the time being, patients with tumors smaller than 1 cm can be safely observed, while those with 1- to 2-cm NF-PNETs are best served by individualized care based on factors set forth in the North American Neuroendocrine Tumor Society guidelines.”
    Surgery vs Observation for Patients With Small Pancreatic Neuroendocrine Tumors  
    Aziz H, Howe JR, Pawlik TM
    JAMA Surgery May 2021 Volume 156, Number 5 
Practice Management

  • “ED radiologists may be trained as ED radiologists or may develop the necessary skills and adopt the subspecialty. Choosing radiologists with the correct traits such as being a “night owl” and remaining calm under pressure and implementing an acceptable work schedule such as shift length of 9–10 h and a “one week on, two weeks off” schedule contribute to sustainability of the position. Strategies to address the unique stressors and workflow challenges of overnight emergency radiology coverage are also presented. Workflow facilitators including trainees, PAs, radiology assistants, and clerks all have roles to play in managing high case volumes and in making sure that the service is well staffed. Usage of artificial intelligence software is the latest technique to streamline workflow by identifying cases which should be prioritized on a busy worklist. Implementing such strategies will maintain quality of care for patients regardless of time of day as well as sustainability and quality of life for overnight emergency radiologists.”
    Update on establishing and managing an overnight emergency radiology division.  
    Scheinfeld, M.H., Dym, R.J.  
    Emerg Radiol (2021).
  • "On the other hand, there are also disadvantages to having a dedicated overnight ED radiology division. Overnight radiologists are hired at a premium due to the undesirable work hours and relative scarcity of these radiologists. In one report, there was an 18% salary premium for overnight radiologists compared to daytime radiologists. ED radiology attendings may encounter cases with new devices, unusual prior surgeries or rare diagnoses which are unfamiliar to emergency radiologists such that their interpretations may be inferior to a subspecialist in that area. Furthermore, some subspecialty-level subtleties may never be detected. Finally, it has been argued that on-hand ED radiologists may result in a loss of trainee independence, possibly impacting education and development of confidence.”
    Update on establishing and managing an overnight emergency radiology division.  
    Scheinfeld, M.H., Dym, R.J.  
    Emerg Radiol (2021).
  • "Practically speaking, staffing an emergency radiologist or multiple emergency radiologists at night will only be sustainable if there are ample overnight imaging cases to be read and there is financing for the division’s radiologists. A practical target would be an average of 8–10 thousand wRVU per radiologist per year, with adjustments for cFTE (clinical full-time equivalent) for each faculty member. Depending on the exact practice situation, this volume may derive purely from the ED or also from STAT inpatient exams. The exact wRVU target should vary based on case-mix as well as the amount of time spent on non-interpretive tasks and preliminary interpretations, as these efforts are not captured by the radiologist’s wRVU tally.”
    Update on establishing and managing an overnight emergency radiology division.  
    Scheinfeld, M.H., Dym, R.J.  
    Emerg Radiol (2021).
  • "Stress refers to too much physical demand or too much mental demand. Burnout refers to a state of exhaustion where there is a lack of motivation, a sense of detachment, feelings of ineffectiveness and lack of accomplishment, and a perceived lack of control. In a 2011 survey, emergency medicine physicians were found to have the highest burnout rate among physicians. Many of the factors contributing to burnout in ED clinicians are also found in ED radiologists, including high volume, unpredictable volume, and strong turnaround time pressures. A survey by Hanna et al. found that emergency radiologists who do no night shift work had 2.2 times higher odds of enjoying their job compared to those who worked 17 or more weeks of night shifts per year (i.e., the equivalent of a “one week on, 2 weeks off” schedule).”
    Update on establishing and managing an overnight emergency radiology division.  
    Scheinfeld, M.H., Dym, R.J.  
    Emerg Radiol (2021).
  • "How to foster job satisfaction depends on the individual. Some will appreciate the position more if they remain engaged with other radiologists and functions in the department, while others may prefer to work their overnight shifts and then be uninvolved with other departmental pursuits during their time off. Some overnight radiologists may enjoy the opportunity to work scheduled or moonlighting daytime shifts in order to participate in the daytime activities of the department and to interact with the daytime radiologists. Avoiding working in isolation, by either working with other attendings, trainees or both, can decrease stress by allowing for sharing of responsibilities and having someone to discuss challenging cases with. Last, engaging in non-radiology interests, maintaining health and wellness and getting adequate exercise are all important to balance a job which involves many uninterrupted sedentary hours of sitting (or standing) at a PACS workstation.”
    Update on establishing and managing an overnight emergency radiology division.  
    Scheinfeld, M.H., Dym, R.J.  
    Emerg Radiol (2021).
  • "Regarding shift length, as noted above, a shift length less than or equal to 9 h was associated with increased job satisfaction. Also, importantly, using a large teleradiology database of 2.9 million cases, errors were found to peak between 10 and 12 h into a shift. A similar increase in errors was found for residents after working 10 h. These factors suggest that a shift length of 9–10 h would be ideal.”
    Update on establishing and managing an overnight emergency radiology division.  
    Scheinfeld, M.H., Dym, R.J.  
    Emerg Radiol (2021).
  • “Careful consideration must be given to exams that are part of inter-departmental “turf-battles” during the day (e.g., vascular ultrasound or obstetric ultrasound). From a political standpoint, it may be undesirable to “cover” the other department that has the primary responsibility for the examination during the day. Furthermore, the technologists and radiologists may not have enough experience performing and reading these exams and having radiology cover only during off-hours may therefore provide suboptimal patient care. On the other hand, performing and reading these exams may allow for more complete usage of imaging equipment and staff and may provide trainee exposure to certain exams which they do not see during normal business hours. Furthermore, providing the service well during off-hours provides a foothold into expanding the department’s role in the exam, which may ultimately extend into normal business hours. Each department must take these factors into consideration when deciding whether to provide these services to the ED during off-hours.”
    Update on establishing and managing an overnight emergency radiology division.  
    Scheinfeld, M.H., Dym, R.J.  
    Emerg Radiol (2021).
  • "ED radiology divisions are rapidly becoming a common addition to US radiology departments, particularly for overnight coverage. Forming such a division presents unique challenges as the practice functions differently than most other radiology divisions. In order to attract and retain quality emergency radiologists, it is important that these divisions devise a structure and schedule that will be sustainable for their radiologists in the long term and will not increase the chances of “burnout” and resultant high radiologist turnover. Factors such as number of shifts and time frame of shifts are key variables to consider, and it is also critical to staff divisions such that the volume of imaging is manageable for radiologists and will allow for expeditious turnaround times.”
    Update on establishing and managing an overnight emergency radiology division.  
    Scheinfeld, M.H., Dym, R.J.  
    Emerg Radiol (2021).
Stomach

  • “Cronkhite-Canada syndrome (CCS) is a rare nonhereditary disease characterized by diffuse gastrointestinal hyperplastic polypoid lesions and ectodermal symptoms such as pigmentation, alopecia and onychatrophia. Since Cronkhite and Canada first reported about this syndrome in 1955, more than 500 cases have been reported worldwide, the majority of which were from Japan. The etiology of CCS is currently unknown, and the association between gastrointestinal polyposis and ectodermal symptoms is undetermined.”
    “Cronkhite-Canada Syndrome Successfully Treated by Corticosteroids before Presenting Typical Ectodermal Symptoms.”  
    Murata, Kazumoto et al.  
    Case reports in gastroenterology vol. 14,3 561-569. 30 Oct. 2020
  • “Cronkhite-Canada syndrome (CCS) is a noninherited condition associated with high morbidity and characterized by gastrointestinal hamartomatous polyposis, alopecia, onychodystrophy, hyperpigmentation, and diarrhea.”
    Cronkhite-Canada syndrome: an acquired condition of gastrointestinal polyposis and dermatologic abnormalities.
    Sweetser S, Boardman LA.
    Gastroenterol Hepatol (N Y). 2012 Mar;8(3):201-3. 
  • “Polyps in CCS patients can develop throughout the gastrointestinal tract (except for the esophagus) and are non-neoplastic hamartomas. Nevertheless, there is concern that CCS polyps may possess malignant potential, as evidenced by the dysplastic intestinal changes noted by Seshadri and coworkers and by reports of gastric, colon, and rectal cancers in patients with CCS.”
    Cronkhite-Canada syndrome: an acquired condition of gastrointestinal polyposis and dermatologic abnormalities.
    Sweetser S, Boardman LA.
    Gastroenterol Hepatol (N Y). 2012 Mar;8(3):201-3. 
  • “The diagnosis of CCS should be considered in patients with gastrointestinal hamartomatous polyps, diarrhea, and the dermatologic triad of alopecia, hyperpigmentation, and onychodystro-phy. Malignant transformation of CCS polyps may occur, and the risk of colorectal cancer may warrant aggressive screening in CCS patients. Immunosuppression with corticosteroids or long-term azathioprine therapy may eradicate or lessen manifestations of CCS.”
    Cronkhite-Canada syndrome: an acquired condition of gastrointestinal polyposis and dermatologic abnormalities.
    Sweetser S, Boardman LA.
    Gastroenterol Hepatol (N Y). 2012 Mar;8(3):201-3. 
  • Dieulafoy's lesion (or Dieulofoy lesion) is a medical condition characterized by a large tortuous arteriole most commonly in the stomach wall (submucosal) that erodes and bleeds. It can present in any part of the gastrointestinal tract.[2] It can cause gastric hemorrhage[3] but is relatively uncommon. It is thought to cause less than 5% of all gastrointestinal bleeds in adults. It was named after French surgeon Paul Georges Dieulafoy, who described this condition in his paper "Exulceratio simplex: Leçons 1-3" in 1898.
  • “A Dieulafoy lesion describes a tortuous, submucosal artery in the gastrointestinal tract—most commonly the posterior stomach—that penetrates through the mucosa over time, eventually perforating to cause severe gastrointestinal bleeding. Due to its insidious onset, tendency to cause intermittent but severe bleeding, and difficulty of endoscopic diagnosis, Dieulofoy lesion has a very high mortality rate. Although originally thought not to be a radiologically diagnosable entity, Dieulofoy lesions can be seen at enhanced CT of the abdomen.”
    Dieulofoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • “A Dieulafoy lesion describes a tortuous, submucosal artery in the gastrointestinal tract—most commonly the posterior stomach—that penetrates through the mucosa over time, eventually perforating to cause severe gastrointestinal bleeding. The lesion is not associated with surrounding ulcer or inflammation. Due to its insidious onset, tendency to cause intermittent but severe bleeding, and difficulty of diagnosis, a Dieulofoy lesion has up to an 80% mortality rate. Due to intermittent and heavy bleeding, initial endoscopic evaluation often does not provide accurate diagnosis of Dieulofoy lesions.”
    Dieulofoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • "Dieulafoy lesions are twice as common in men as they are in women and can occur at any age, most commonly presenting in the fifth decade. Patients usually present with massive bleeding, most often without an associated prodrome of gastric complaints, which can be seen with ulcer disease. Interestingly, a large portion of presentations occur in patients that are already hospitalized for a different condition, pointing towards physiological stress as an inciting factor for arterial perforation.”
    Dieulafoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • "The CT findings of a Dieulafoy lesion include an abnormally enlarged submucosal vessel, which may appear serpentine, linear, or as a non-specific blush of apparent mucosal/submucosal contrast medium. Contrast medium within the bowel or stomach lumen makes the lesion more conspicuous and suggests active extravasation. It is important to view the gastric mucosa and bowel in as many imaging planes as possible, preferably at least two, as sagittal or coronal imaging may make the abnormally large submucosal vessel more easily identifiable.”
    Dieulafoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • "Near-definitive diagnosis of a Dieulafoy lesion can be obtained with enhanced CT of the abdomen. Optimal studies are performed in the arterial phase of intravenous contrast enhancement without administration of oral contrast material. CTA shows an enlarged submucosal arteriole in the gastrointestinal submucosal layer with or without active contrast medium extravasation into the lumen. Familiarity with the lesion and its manifestations can help guide radiologists to make the correct diagnosis in cases where endoscopy or standard angiography have failed. CT diagnosis can then help guide endoscopic and endovascular localization and treatment, ultimately improving patient outcomes.”
    Dieulafoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • “Watermelon stomach (WMS), or gastric antral vascular ectasia, is an uncommon but clinically important cause of chronic occult or overt gastrointestinal (GI) blood loss. Patients typically present with symptomatic anemia and hemoccult positive stools. Although the diagnosis is based primarily on the typical endoscopic appearance, the lesion may be overlooked on initial evaluation or interpreted as "gastritis." Gastric biopsy may be helpful in confirming the diagnosis by showing vascular ectasia, typically without inflammation. WMS is idiopathic but is often associated with autoimmune diseases or cirrhosis of the liver. The majority of patients with classic WMS are elderly and female.”
  • “Gastric antral vascular ectasia (GAVE) is a rare entity with unique endoscopic appearance described as "watermelon stomach." It has been associated with systemic sclerosis but the pathophysiological changes leading to GAVE have not been explained and still remain uncertain.”
    Gastric Antral Vascular Ectasia in Systemic Sclerosis: Current Concepts.  
    Parrado RH et al.  
    Int J Rheumatol. 2015;2015:762546.
  • “Gastric antral vascular ectasia, or “watermelon stomach,” is a rare cause of chronic gastrointestinal bleeding, characterized endoscopically by a distinctive appearance of prominent red vascular folds traversing the gastric antrum and radiating to the pyloric sphincter; this appearance has been likened to the stripes on a watermelon rind.”
    Gastric antral vascular ectasia ("watermelon stomach"): radiologic findings.  
    Urban BA, Jones B, Fishman EK, Kern SE, Ravich WJ.  
    Radiology. 1991 Feb;178(2):517-8.
  • “Gastric antral vascular ectasia primarily affects women (9:1 female-to-male ratio) aged 56-76 years, and is associated with liver cirrhosis (37%) and achlorhydria (35%). The usual symptoms are iron-deficiency anemia and melena due to chronic gastrointestinal bleeding from the dilated, superficial, and easily traumatized vessels. Antrectomy is curative, but endoscopic treatment with heat probes or lasers has shown promise.”
    Gastric antral vascular ectasia ("watermelon stomach"): radiologic findings.  
    Urban BA, Jones B, Fishman EK, Kern SE, Ravich WJ.  
    Radiology. 1991 Feb;178(2):517-8.
  • “In our patient, the findings of prominent mucosal folds extending from the pyloric channel on upper gastrointestinal series and the thickened antral wall on CT scans correlate well with the known pathologic appearance of gastric antral vascular ectasia. Histologically, antral thickening results from a combination of foveolar and fibromuscular hyperplasia. Grossly, the antral fold prominence appears to result from bunching of the mucosa in the thickened, hypercontractile antrum.”
    Gastric antral vascular ectasia ("watermelon stomach"): radiologic findings.  
    Urban BA, Jones B, Fishman EK, Kern SE, Ravich WJ.  
    Radiology. 1991 Feb;178(2):517-8.
  • “Renal cell carcinoma (RCC) represents above 3 % of all cancers, with the highest incidence occurring in Western countries. At diagnosis, above 25 % of patients with RCC present an advanced disease, including locally invasive or metastatic cancer. The mean survival time of patient with metastatic RCC is approximately 13 months.The most common metastatic RCC sites are the lung and bone (up to 60 % and 40 % of patients with metastases). However, unusual sites of metastasis are characteristics of RCC and any organ site can be involved, including the thyroid, pancreas, skeletal muscle and skin.”
    Are gastric metastases of renal cell carcinoma really rare? A case report and systematic review of the literature
    Thomas Prudhomme et al.
    International Journal of Surgery Case Reports, Volume 82,2021
  • "At RCC gastric metastasis diagnosis, 73 % of the patients presented multiple metastatic sites, mainly lungs and bones. The median patients age (IQR) was 66.0 (60.0–69.0) years, of whom 74 % were men. The median time (IQR) between the diagnosis of RCC and metachronous gastric metastasis was 5.0 (2.0–9.5) years. 3 patients presented RCC with synchronous gastric metastasis. 35 % of the patients had a surgical treatment, 16 % an endoscopic treatment, 23 % a systemic therapy and 26 % a palliative treatment. Endoscopic treatment was mucosal and submucosal resection without positive surgical margins. Median patient survival (IQR), after treatment, was 6 months.”
    Are gastric metastases of renal cell carcinoma really rare? A case report and systematic review of the literature
    Thomas Prudhomme et al.
    International Journal of Surgery Case Reports, Volume 82,2021
  • "Renal cell carcinoma is the most common solid lesion within the kidney and accounts approximately 90 % of all kidney malignancies. It comprises different RCC subtypes with specific histopathological characteristics. Clear cell RCC is the most common histopathological entities of RCC and clear cell RCC has worse prognosis compared to other histopathological entities, even after stratification for stage and grade. Indeed, clear cell RCC has an abundant blood supply and can metastasize to several organs. Metastasis routes include hematogenous, lymphogenous, renal capsule, renal pelvis and ureteric routes, which explains the wide variety of organs that can be RCC metastatic sites.”
    Are gastric metastases of renal cell carcinoma really rare? A case report and systematic review of the literature
    Thomas Prudhomme et al.
    International Journal of Surgery Case Reports, Volume 82,2021
Vascular

  • Dieulafoy's lesion (or Dieulofoy lesion) is a medical condition characterized by a large tortuous arteriole most commonly in the stomach wall (submucosal) that erodes and bleeds. It can present in any part of the gastrointestinal tract.[2] It can cause gastric hemorrhage[3] but is relatively uncommon. It is thought to cause less than 5% of all gastrointestinal bleeds in adults. It was named after French surgeon Paul Georges Dieulafoy, who described this condition in his paper "Exulceratio simplex: Leçons 1-3" in 1898.
  • “A Dieulafoy lesion describes a tortuous, submucosal artery in the gastrointestinal tract—most commonly the posterior stomach—that penetrates through the mucosa over time, eventually perforating to cause severe gastrointestinal bleeding. Due to its insidious onset, tendency to cause intermittent but severe bleeding, and difficulty of endoscopic diagnosis, Dieulafoy lesion has a very high mortality rate. Although originally thought not to be a radiologically diagnosable entity, Dieulafoy lesions can be seen at enhanced CT of the abdomen.”
    Dieulafoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • “A Dieulafoy lesion describes a tortuous, submucosal artery in the gastrointestinal tract—most commonly the posterior stomach—that penetrates through the mucosa over time, eventually perforating to cause severe gastrointestinal bleeding. The lesion is not associated with surrounding ulcer or inflammation. Due to its insidious onset, tendency to cause intermittent but severe bleeding, and difficulty of diagnosis, a Dieulafoy lesion has up to an 80% mortality rate. Due to intermittent and heavy bleeding, initial endoscopic evaluation often does not provide accurate diagnosis of Dieulafoy lesions.”
    Dieulafoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • "Dieulafoy lesions are twice as common in men as they are in women and can occur at any age, most commonly presenting in the fifth decade.Patients usually present with massive bleeding, most often without an associated prodrome of gastric complaints, which can be seen with ulcer disease. Interestingly, a large portion of presentations occur in patients that are already hospitalized for a different condition, pointing towards physiological stress as an inciting factor for arterial perforation.”
    Dieulafoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • "The CT findings of a Dieulafoy lesion include an abnormally enlarged submucosal vessel, which may appear serpentine, linear, or as a non-specific blush of apparent mucosal/submucosal contrast medium. Contrast medium within the bowel or stomach lumen makes the lesion more conspicuous and suggests active extravasation. It is important to view the gastric mucosa and bowel in as many imaging planes as possible, preferably at least two, as sagittal or coronal imaging may make the abnormally large submucosal vessel more easily identifiable.”
    Dieulafoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
  • "Near-definitive diagnosis of a Dieulafoy lesion can be obtained with enhanced CT of the abdomen. Optimal studies are performed in the arterial phase of intravenous contrast enhancement without administration of oral contrast material. CTA shows an enlarged submucosal arteriole in the gastrointestinal submucosal layer with or without active contrast medium extravasation into the lumen. Familiarity with the lesion and its manifestations can help guide radiologists to make the correct diagnosis in cases where endoscopy or standard angiography have failed. CT diagnosis can then help guide endoscopic and endovascular localization and treatment, ultimately improving patient outcomes.”
    Dieulafoy lesion: CT diagnosis of this lesser-known cause of gastrointestinal bleeding
    A. Batouli et al.
    Clinical Radiology,Volume 70, Issue 6,2015,Pages 661-666
© 1999-2021 Elliot K. Fishman, MD, FACR. All rights reserved.