Imaging of the porta hepatis: spectrum of disease.

A wide array of pathologic conditions can arise within the porta hepatis, which encompasses the portal triad (the main portal vein, common hepatic artery, and common bile ducts), lymphatics, nerves, and connective tissue. Major vascular diseases of the portal triad include thrombosis, stenosis, and aneurysm. Portal vein thrombosis can complicate liver cirrhosis and hepatocellular carcinoma and has important therapeutic implications. Hepatic artery thrombosis and stenosis require immediate attention to reduce graft loss in liver transplant recipients. Congenital (eg, choledochal cyst) and acquired (benign and malignant) diseases of the biliary system can manifest as mass lesions in the porta hepatis. Lymphadenopathy can arise from neoplastic and nonneoplastic entities. Uncommon causes of mass lesions arise from nerves (eg, neurofibroma, neurofibrosarcoma) and connective tissue (sarcomas) and are rare. The hepatoduodenal ligament is a peritoneal reflection at the porta hepatis and is an important route for the spread of pancreatic and gastrointestinal cancers. Imaging plays a major role in diagnosis and enables appropriate management. Ultrasonography accurately demonstrates anatomic variations and pathologic conditions and is the initial modality of choice for detection of vascular and biliary lesions. Multidetector computed tomography and magnetic resonance imaging allow characterization and differentiation of various masses in the porta hepatis. Imaging-guided interventions, including embolization and stent placement, also play a key role in disease management.

Imaging of tuberculosis of the abdominal viscera: beyond the intestines.

There is an increasing incidence of both intra- and extra-thoracic manifestations of tuberculosis, in part due to the AIDS epidemic. Isolated tubercular involvement of the solid abdominal viscera is relatively unusual. Cross-sectional imaging with ultrasound, multidetector computed tomography (CT), and magnetic resonance imaging (MRI) plays an important role in the diagnosis and post treatment follow-up of tuberculosis. Specific imaging features of tuberculosis are frequently related to caseous necrosis, which is the hallmark of this disease. However, depending on the type of solid organ involvement, tubercular lesions can mimic a variety of neoplastic and nonneoplastic conditions. Often, cross-sectional imaging alone is insufficient in reaching a conclusive diagnosis, and image-guided tissue sampling is needed. In this article, we review the pathology and cross-sectional imaging features of tubercular involvement of solid abdominopelvic organs with a special emphasis on appropriate differential diagnoses.

Current concepts in the imaging of uterine sarcoma.

Recent advances in genetics and pathology have improved our understanding of diagnosis and staging of uterine sarcomas. The major types of uterine sarcomas include leiomyosarcoma, low-grade endometrial stromal sarcoma, undifferentiated endometrial sarcoma, adenosarcoma and carcinosarcoma. The distinctive biological behavior and poor overall survival of uterine sarcoma create challenges in the management of these tumors. We herein present a comprehensive review of taxonomy, epidemiology, pathology, imaging findings and natural history of a wide spectrum of uterine sarcomas.

Spectrum of medication-induced complications in the abdomen: role of cross-sectional imaging.

OBJECTIVE: This article provides a comprehensive review of the role of MDCT and MRI in the diagnosis of drug-induced complications in the abdomen and pelvis in adults. A systematic organ-based review of these complications is presented, including but not limited to hepatic changes after chemotherapy, renal complications such as tumor lysis syndrome and lithium nephropathy, gastrointestinal manifestations, various opportunistic infections and secondary neoplasms, mycotic aortic aneurysm from intravesical bacille Calmette-Guérin, complications of anticoagulant therapy, and oral contraceptives. CONCLUSION: Advancements in imaging have led to recognition of radiologic features of previously unsuspected diseases. Occasionally, imaging may also identify effects of treatments instituted for these diseases. Consequently, imaging plays a critical role in the accurate diagnosis of a broad spectrum of drug-induced complications in the abdomen, both in emergent and nonemergent settings. Knowledge of the natural history, clinical manifestations, and salient imaging features of these entities is crucial to facilitate accurate clinical diagnosis in a timely fashion.

Benign biliary strictures: a current comprehensive clinical and imaging review.

OBJECTIVE: There is a wide spectrum of nonneoplastic causes of biliary stricture that can pose a significant challenge to clinicians and radiologists. Imaging plays a key role in differentiating benign from malignant strictures, defining the extent, and directing the biopsy. We describe the salient clinical and imaging manifestations of benign biliary strictures that will help radiologists to accurately diagnose these entities. CONCLUSION: Accurate diagnosis and management are based on correlating imaging findings with epidemiologic, clinical, and laboratory data. Cross-sectional imaging modalities permit precise localization of the site and length of the segment involved, thereby serving as a road map to surgery, and permit exclusion of underlying malignancy.

Comprehensive update on select immune-mediated gastroenterocolitis syndromes: implications for diagnosis and management.

There is a heterogeneous group of noninfectious gastroenterocolitis syndromes that are characterized by immune dysregulation. Recent advances in pathologic analysis have allowed for better characterization of many of these disorders. Some entities demonstrate characteristic disease distribution, epidemiologic features, natural history, and response to specific therapy. For instance, celiac disease occurs in genetically susceptible individuals who are sensitive to gluten, eosinophilic esophagitis is an immune response to ingested allergens, and microscopic colitis predominantly occurs in older patients with chronic diarrhea and is induced or exacerbated by drugs. Eosinophilic gastroenteritis has a variety of clinical and imaging manifestations. Crohn disease and ulcerative colitis are multifactorial immune-mediated chronic inflammatory disorders and have become increasingly prevalent in recent years. Multidetector computed tomography and magnetic resonance imaging provide valuable information that may be used to diagnose these conditions, guide treatment, and assess changes after treatment, and the role of imaging in evaluating response to therapy continues to evolve and expand.

Tumor response evaluation in oncology: current update.

Quantification of tumor burden and assessment of changes in tumor size after chemotherapy are commonly performed to evaluate treatment response in oncology trials. Validation and adoption of different criteria have been attempted in the past to achieve uniformity in scanning techniques and measurement metrics so that comparison of different oncological trials is feasible. Response assessment of solid tumors is usually consisted of either bidimensional (World Health Organization criteria) or unidimensional (Response Evaluation Criteria in Solid Tumors [RECIST] guidelines) measurement of tumors before and after chemotherapy. RECIST 1.1 criteria have been recently published. In this article, we try to provide a comprehensive review of the tumor response evaluation guidelines that were recently updated in attempts to overcome limitations of the previous criteria as well as incorporate recent advances in imaging techniques.

Clinical syndromes associated with ovarian neoplasms: a comprehensive review.

Functional ovarian neoplasms have unique clinical manifestations related to hormone overproduction and may give rise to a broad spectrum of clinical syndromes. Sex cord-stromal tumors, the most common functional ovarian neoplasms, are associated with either hyperestrogenism (as in granulosa cell tumor and thecoma) or hyperandrogenism (as in Sertoli-Leydig cell tumor and Leydig cell tumor). Other, less common ovarian neoplasms that may have endocrine or nonendocrine syndromic manifestations include germ cell tumors associated with the excessive production of human chorionic gonadotropin (eg, choriocarcinoma, dysgerminoma), monodermal teratomas (eg, carcinoid tumor, struma ovarii) associated with carcinoid syndrome and hyperthyroidism, and primary epithelial ovarian cancers associated with paraneoplastic syndromes. The application of diagnostic algorithms based on patient demographic information, clinical manifestations, laboratory findings, and cross-sectional imaging features may help identify ovarian neoplasms in complex clinical settings.

Gamut of focal fatty lesions in the liver: imaging manifestations with emphasis on magnetic resonance imaging.

A wide variety of hepatic lesions contain fat within them in a proportion good enough to be demonstrable on imaging. With the biological behaviors quite different from each other, they form a clinico-radio-pathologic spectrum worth remembering. We present a review of common and uncommon focal hepatic lesions containing fat (micro- and macroscopic) within them and emphasize the role of imaging in their diagnosis.

A clinical and radiologic review of uncommon types and causes of pancreatitis.

Acute pancreatitis is one of the most common conditions for which emergent imaging is indicated. Alcohol consumption and cholelithiasis are the most common causes of acute pancreatitis in adults, whereas the majority of cases in children are idiopathic or secondary to trauma. A wide variety of structural and biochemical abnormalities may also cause pancreatitis. Although in some cases it is difficult to identify the specific cause of the disease radiologically, certain uncommon types of acute or chronic pancreatitis may have unique imaging features that can help the radiologist make an accurate diagnosis. These unusual types include autoimmune pancreatitis, groove pancreatitis, tropical pancreatitis, hereditary pancreatitis, and pancreatitis in ectopic or heterotopic pancreatic tissue. Pancreatitis may occasionally be seen in association with cystic fibrosis or pancreas divisum, or secondary to worm infestation of the pancreaticobiliary tree (eg, by Ascaris lumbricoides). In addition, primary pancreatic and duodenal masses may occasionally manifest as acute or recurrent acute pancreatitis. Knowledge of the classic imaging findings of these entities allows prompt recognition of the relevant pathologic condition, thereby preventing misdiagnosis and subsequent inappropriate or delayed management.

Real time spatial compound ultrasound in the evaluation of meniscal injuries: a comparison study with conventional ultrasound and MRI.

The aim of this study was to compare real time spatial compound ultrasound (RTCS) and conventional ultrasound with MRI in the evaluation of meniscal injuries. Thirty five patients with clinical suspicion of meniscal injury underwent ultrasound of knee alternating between conventional and compound sonography followed by MRI of the knee on a 1.5 T MR system. The images were compared for their quality and ability to detect meniscal tear. Compound ultrasound significantly improved definition of soft tissue planes, reduced speckle and other noise, improved contrast resolution (p value<0.05) with improved confidence in detection of tears in doubtful cases. Interobserver variability was seen only for conventional ultrasound and the sensitivity, specificity, accuracy were 83.3%, 87.5% and 85.7% for the first observer and 80%, 87.5% and 84.3% for second observer. For compound ultrasound it was same for both the observers with sensitivity, specificity and accuracy being 90% each. Although compound ultrasound improves image quality in the evaluation of meniscal injuries the benefit with respect to detection of tears is only marginal. It is a valuable tool for screening the patients before MRI and we recommend that instead of conventional ultrasound, compound ultrasound should be routinely used for sonographic evaluation of meniscal injuries.