Publications by authors named "Alexander Kagen"

The purpose of this article is to provide a comprehensive review of the imaging findings along with histopathologic correlation of mature (benign) teratomas and malignant ovarian teratomas, which include both immature teratomas and malignant degeneration of mature teratomas. The radiologist's ability to provide an accurate diagnosis plays an essential role in guiding the interdisciplinary care of patients with malignant teratomas and improving their outcomes.

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Objective: Effort has been made to minimize the burden of non-interpretive tasks (NITs), in particular by hiring and training non-radiologist support staff as reading room coordinators (RRCs). Our medical center recruited and trained senior medical students from our affiliated school of medicine to work alongside on-call radiology residents as RRCs.

Methods: A 12-month Malpractice Carrier monetary grant was acquired to fund medical students at with the aim to reduce malpractice risk.

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Background: Intraoperative observation of Scarpa's fascia (SF) has suggested attenuation in the periumbilical region. This study's purpose was to objectively evaluate SF anatomy in the periumbilical region and assess clinical outcomes of a novel, modified SF closure technique of transverse abdominal wall incisions that only reapproximates SF where it is definitively present.

Methods: Women were identified who had undergone abdominal magnetic resonance (MR) angiography before their abdominal-based autologous breast reconstruction that used the modified SF closure technique.

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Background: Deep learning models are increasingly informing medical decision making, for instance, in the detection of acute intracranial hemorrhage and pulmonary embolism. However, many models are trained on medical image databases that poorly represent the diversity of the patients they serve. In turn, many artificial intelligence models may not perform as well on assisting providers with important medical decisions for underrepresented populations.

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Preoperative vascular imaging has been shown to be beneficial before free tissue transfer procedures, especially for deep inferior epigastric perforator flap breast reconstruction. Although computerized tomography angiography and magnetic resonance angiogram are increasingly frequently performed, there is no standardized method for recording, analyzing, and communicating the vast amount of clinically relevant information that is obtained from these tomographic imaging studies. Herein, the authors propose a new visual language system for preoperative imaging called "FlapMap," which allows for the creation of a clinically actionable, easily understood, and easily communicated single image that aids in preoperative planning before microvascular free tissue transfer.

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Article Synopsis
  • - The study explores the effectiveness of deep learning models utilizing electrocardiogram (ECG) data to improve the specificity of screening for pulmonary embolism (PE), addressing the issue of overusing computed tomography pulmonary angiograms (CTPAs).
  • - Researchers built a cohort of over 21,000 patients and developed three predictive models: one based on ECG data, one on electronic health records (EHR), and a Fusion model combining both, finding the Fusion model significantly outperformed the others in PE detection accuracy.
  • - The findings suggest that integrating ECG waveforms with clinical data can enhance the specificity and overall performance in detecting PE, offering a potential improvement over traditional clinical risk scoring methods.
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Autosomal dominant polycystic kidney disease (ADPKD) eventually leads to end stage renal disease (ESRD) with an increase in size and number of cysts over time. Progression to ESRD has previously been shown to correlate with total kidney volume (TKV). An accurate and relatively simple method to perform measurement of TKV has been difficult to develop.

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Aims: Lymphoepithelioma-like carcinomas (LELCs) are uncommon epithelial cancers characteristically showing two distinct components consisting of malignant epithelial cells and prominent dense lymphoid infiltrate. Hepatic LELCs consist of two types, the lymphoepithelioma-like hepatocellular carcinoma and lymphoepithelioma-like cholangiocarcinoma (LEL-CCA), with the latter being strongly associated with Epstein-Barr virus (EBV).

Methods And Results: We present a series of three cases of intrahepatic biliary EBV-associated LEL tumours in which the biliary epithelial component showed a distinctly benign appearance, instead of the usual malignant epithelial features of a typical CCA or EBV-associated LEL-CCA.

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Objective: The objectives of this study are to determine the efficacy of a roster of clinical factors in identifying risk for renal insufficiency in emergency department (ED) patients requiring intravenous contrast-enhanced CT scan (IVCE-CT) and to help mitigate potential for developing contrast-induced nephropathy (CIN).

Methods: A review was conducted of consecutive ED patients who received IVCE-CT during a 4-month period in our urban ED. The values of ED serum creatinine (SCr) performed were tabulated.

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As modern abdominal imaging equipment advances, pancreatic lesion detection improves. Most of these lesions are incidental, and present a conundrum to the clinician and create great anxiety to the patient until a final diagnosis is made. For the practicing physician, the plethora of diagnostic options is overwhelming.

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Popliteal venous aneurysms (PVAs) are rare and may represent a cause of recurrent pulmonary embolism. We present a case of PVA identified on ultrasound for deep venous thrombosis in a 27-year-old female with popliteal fossa pain. We discuss our recommendations for treatment and present a review of the previously reported cases.

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Background: The use of heterotopic vascularized lymph node transfer (HVLNT) for the treatment of lower extremity lymphedema is still evolving. Current techniques, either place the lymph nodes in the thigh without a skin paddle or at the ankle requiring an unsightly and often bulky skin paddle for closure. We explored the feasibility of doing a below-knee transfer without a skin paddle using the medial sural vessels as recipient vessels and report our experience in 21 patients.

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TensorFlow is a second-generation open-source machine learning software library with a built-in framework for implementing neural networks in wide variety of perceptual tasks. Although TensorFlow usage is well established with computer vision datasets, the TensorFlow interface with DICOM formats for medical imaging remains to be established. Our goal is to extend the TensorFlow API to accept raw DICOM images as input; 1513 DaTscan DICOM images were obtained from the Parkinson's Progression Markers Initiative (PPMI) database.

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 The medial sural vessels have been used extensively as donor vessels in free tissue transfer; however, there is sparse literature detailing their use as recipient vessels. The few existing reports involve small numbers of patients and describe operative approaches that are unnecessarily cumbersome. We explored our experience in free tissue transfer to the medial sural vessels and share a simplified operative approach to this recipient site.

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• Chronic traumatic AVF leads to significant morbidity when allowed to progress. • Traumatic AVF may be approached with endovascaular, open, and hybrid techniques. • We describe a traumatic AVF which was left to progress for over 30 years.

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Purpose: The evolving health care landscape demands a multidisciplinary approach to care and increased emphasis on patient engagement. Radiologists may play an important role in this respect, by improving patient agency and understanding through direct patient interaction. The purpose of this study is to assess patient preferences and perceptions regarding direct communication with radiologists, focusing on a medically underserved demographic.

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Purpose: To assess the diagnostic value of a fast scoring system based on non-invasive cross-sectional imaging to predict portal hypertension (PH) in patients with liver disease.

Methods: In this retrospective study, we included patients who underwent contrast-enhanced CT or MRI within 3 months of hepatic venous pressure gradient (HVPG) measurements. Two independent observers provided an imaging-based scoring system (max of 9): number of variceal sites, volume of ascites, and spleen size.

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Advances in microsurgical techniques have improved autologous reconstructions by providing new donor site options while decreasing donor site morbidity. Various preoperative imaging modalities have been studied to assess the relevant vascular anatomic structures, with magnetic resonance (MR) angiography traditionally lagging behind computed tomography (CT) with respect to spatial resolution. Blood pool MR angiography with gadofosveset trisodium, a gadolinium-based contrast agent with extended intravascular retention, has allowed longer multiplanar acquisitions with resultant voxel sizes similar to or smaller than those of CT and with improved signal-to-noise ratio and soft-tissue contrast while maintaining the ability to depict flow with time-resolved imaging.

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The current algorithm for the imaging diagnosis of hepatocellular carcinoma accurately detects large, progressed tumors displaying the classical imaging features of arterial hyperenhancement with 'washout' and/or 'capsule' appearance. Liver MRI with the relatively newer hepatobiliary agent, gadoxetate disodium, provides information on hepatocellular function in addition to vascularity, facilitates detection of small progressed tumors, as well as early/vaguely nodular tumors, and shows promise for characterizing hepatocellular carcinoma biology. Prediction of tumor grade, presence of biliary and stem cell markers, microvascular invasion, future hypervascularization and post-treatment recurrence have all been studied with gadoxetate disodium-enhanced MRI with encouraging results.

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Vascularized groin lymph node transfer (VGLNT) has been successfully used to treat lymphedema. However, lack of familiarity with the inguinal node anatomy and concerns regarding donor site morbidity have limited its widespread use. The purpose of this study was to use magnetic resonance angiography (MRA) to clarify the inguinal anatomy and provide a reliable method for identifying the location of the superficial transverse inguinal lymph nodes.

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Introduction: Aggressive angiomyxoma (AAM) is a rare, benign mass with propensity for local invasion and recurrence after resection. Infrequently, this tumor can be found arising from the scrotum or cord structures in males.

Aim/methods: A case report is presented followed by a review of relevant literature addressing the diagnosis, imaging, management and follow-up for aggressive angiomyxoma of the scrotum.

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Purpose: To prospectively evaluate comfort and image quality of prostate MRI using two different endorectal (ER) coils.

Materials And Methods: Thirty consecutive patients were prospectively randomized to receive prostate MRI using either a prostate endocoil (PEC) or colorectal endocoil (CEC). Patients and operators were surveyed with regard to endocoil placement.

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Purpose: The use of T2 MR for postimplant dosimetry (PID) after prostate brachytherapy allows more anatomically accurate and precise contouring but does not readily permit seed identification. We developed a reproducible technique for performing MR-CT fusion and compared the resulting dosimetry to standard CT-based PID.

Methods And Materials: CT and T1-weighted MR images for 45 patients were fused and aligned based on seed distribution.

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Objectives: To establish the efficacy of nephrolithotripsy via intercostal access route vs subcostal access route with respect to attained stone-free status, operating time, and complications.

Methods: Percutaneous nephrolithotripsies via the upper pole were performed in 142 patients (93 male, 49 female, age 24-78 years) from 1998 to 2005 at our 4 academic medical centers. Selection criteria for nephrolithotripsy via upper pole access were staghorn calculi > or = 5.

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Objective: The objective of our retrospective study was to provide evidence on the efficacy of the intercostal versus subcostal access route for percutaneous nephrolithotripsy.

Materials And Methods: 642 patients underwent nephrolithotomy or nephrolithotripsy from 1996 to 2005. A total of 127 had an intercostal access tract (11th or 12th); 515 had a subcostal access tract.

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