Victoria Chernyak

Transplant renal artery stenosis: clinical manifestations, diagnosis and therapy

Transplant renal artery stenosis (TRAS) is a well-recognized vascular complication after kidney transplant. It occurs most frequently in the first 6 months after kidney transplant, and is one of the major causes of graft loss and premature death in transplant recipients. Renal hypoperfusion occurring in TRAS results in activation of the renin–angiotensin–aldosterone system; patients usually present with worsening or refractory hypertension, fluid retention and often allograft dysfunction. Flash pulmonary edema can develop in patients with critical bilateral renal artery stenosis or renal artery stenosis in a solitary kidney, and this unique clinical entity has been named Pickering Syndrome. Prompt diagnosis and treatment of TRAS can prevent allograft damage and systemic sequelae. Duplex sonography is the most commonly used screening tool, whereas angiography provides the definitive diagnosis. Percutaneous transluminal angioplasty with stent placement can be performed during angiography if a lesion is identified, and it is generally the first-line therapy for TRAS. However, there is no randomized controlled trial examining the efficacy and safety of percutaneous transluminal angioplasty compared with medical therapy alone or surgical intervention.

Improved parenchymal liver enhancement with extended delay on Gd-EOB-DTPA-enhanced MRI in patients with parenchymal liver disease: associated clinical and imaging factors

AIMnTo establish the effect of prolonged hepatobiliary phase (HBP) delay time on hepatic enhancement in patients with parenchymal liver disease (PLD).nnnMATERIALS AND METHODSnGadoxetate disodium (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) examinations with HBP were obtained after 20- (HBP-20) and 30-minute (HBP-30) delays in patients with PLD. For each patient, the Model for End-Stage Liver Disease (MELD) score, total and direct bilirubin, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), prothrombin time (PT), and partial thromboplastin time (PTT) were recorded. Signal intensities of the liver, main portal vein, and spleen on pre-contrast, HBP-20, and HBP-30 were documented. Signal intensities were used to calculate liver relative enhancement (LRE), liver-spleen index (LSI), and liver-portal vein index (LPI) for HBP-20 and HBP-30. Improved hepatic enhancement was considered if two or more indices were higher on HBP-30 than HBP-20. A logistic regression model was constructed with improved hepatic enhancement as the outcome.nnnRESULTSnOne hundred and twenty-nine patients underwent 142 MRIs. Mean LRE, LSI, and LPI each increased from HBP-20 to HBP-30 (p = 0.004, p < 0.001, and p < 0.001, respectively). Seventy-two point five percent of cases demonstrated improved hepatic enhancement. The odds ratios for improved hepatic enhancement were 0.85 for MELD score (p = 0.02) and 3.2 for the 3 T scanner (p = 0.02), adjusted for age and sex.nnnCONCLUSIONnIncreasing HBP delay to 30 minutes improves hepatic enhancement in patients with PLD, particularly if using a 3 T scanner. This effect is attenuated with higher MELD scores.

MR imaging of renal collecting system with gadoxetate disodium: Feasibility for MR urography

To determine the feasibility of using gadoxetate disodium for MR urography.

Novel Imaging Modalities for Lymph Node Imaging in Urologic Oncology

Accurate lymph node staging in genitourinary (GU) malignancies is important for planning an appropriate treatment and establishing an accurate prognosis. This article discusses the novel imaging techniques for detection of metastases in various GU malignancies, including prostate, bladder, penile, and testicular cancers. Discussion includes nuclear medicine techniques of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT), (11)C-choline and (18)F-choline PET/CT, and ProstaScint scanning, as well as sentinel lymph node mapping. Magnetic resonance (MR) techniques include lymphotropic nanoparticle-enhanced MR imaging and diffusion-weighted MR imaging.

Advances in Imaging in Prostate and Bladder Cancer

Recent advancements in urologic imaging techniques aim to improve the initial detection of urologic malignancies and subsequent recurrence and to more accurately stage disease. This allows the urologist to make better informed treatment decisions. In particular, exciting advances in the imaging of prostate cancer and bladder cancer have recently emerged including the use of dynamic, functional imaging with MRI and PET. In this review, we will explore these imaging modalities, in addition to new sonography techniques and CT, and how they hope to improve the diagnosis and management of prostate and bladder cancer.

Hollow organ abdominal ischemia, part II: clinical features, etiology, imaging findings and management.

Acute hollow organ ischemia commonly presents with acute pain prompting radiologic evaluation and almost always requires urgent treatment. Despite different risk factors and anatomic differences, ischemia is commonly due to low flow states but can also be due to arterial and venous occlusion. Radiologic diagnosis is critical as many present with nonspecific symptoms. Contrast-enhanced computed tomography (CT) is the modality of choice. Magnetic resonance imaging (MRI) is preferred in suspected appendicitis in pregnant patients and is superior in biliary necrosis. This article provides a pictorial review of the CT/MRI features of hollow abdominal organ ischemia while highlighting key clinical features, pathogenesis, and management.

Improving diagnosis of atraumatic splenic lesions, Part III: malignant lesions

Focal atraumatic splenic lesions often pose a diagnostic challenge on cross-sectional imaging. They can be categorized based on etiology, as nonneoplastic, benign neoplastic, and malignant neoplastic (discussed in Part III) lesions, or on prevalence, as common, uncommon, and rare lesions. Familiarity with pertinent clinical parameters, etiology, pathology, prevalence, and ancillary features such as splenomegaly, concomitant hepatic involvement, and extrasplenic findings, in addition to knowledge of imaging spectra of the lesions, can improve diagnostic confidence. Consideration of these factors together can arm the radiologist with the necessary tools to render a more confident diagnosis and thus better aid management.

Improving diagnosis of atraumatic splenic lesions, part II: benign neoplasms/nonneoplastic mass-like lesions

Focal atraumatic splenic lesions often pose a diagnostic challenge on cross-sectional imaging. They can be categorized based on etiology as nonneoplastic, benign neoplastic (discussed in Part II), and malignant neoplastic lesions or on prevalence as common, uncommon, and rare lesions. Familiarity with pertinent clinical parameters, etiology, pathology, prevalence and ancillary features such as splenomegaly, concomitant hepatic involvement, and extrasplenic findings, in addition to knowledge of imaging spectra of the lesions, can improve diagnostic confidence. Consideration of these factors together can arm the radiologist with the necessary tools to render a more confident diagnosis and, thus, better aid management.

Improving diagnosis of atraumatic splenic lesions, part I: nonneoplastic lesions

Focal atraumatic splenic lesions often pose a diagnostic challenge on cross-sectional imaging. They can be categorized based on etiology as nonneoplastic (reviewed in Part I), benign neoplastic, and malignant neoplastic lesions. Lesions can also be characterized based on prevalence as common, uncommon, and rare. Familiarity with pertinent clinical parameters, etiology, pathology, prevalence, and ancillary features such as splenomegaly, concomitant hepatic involvement, and extrasplenic findings, in addition to knowledge of imaging spectra of these lesions, can improve diagnostic confidence. Since the nonneoplastic lesions are usually easily recognized, it is critical that the radiologist identifies them avoiding unnecessary work up.

Renal vein tumor thrombus from metastatic anal gland adenocarcinoma

A 62-year-old female with a history of anal gland adenocarcinoma presents with metastatic disease to the kidney with renal vein tumor thrombus extending into the inferior vena cava (IVC). Metastatic disease to the kidney with renal vein tumor thrombus is extremely rare with only several cases described in the literature. We present the first reported case of metastatic anal gland adenocarcinoma to the kidney with renal vein tumor thrombus.