Sachit K. Verma

Exophytic Renal Masses: Angular Interface with Renal Parenchyma for Distinguishing Benign from Malignant Lesions at MR Imaging

PURPOSE To retrospectively determine whether benign exophytic renal masses can be distinguished from renal cell carcinoma (RCC) on the basis of angular interface at single-shot fast spin-echo (SE) T2-weighted magnetic resonance (MR) imaging. MATERIALS AND METHODS This retrospective study was compliant with HIPAA and was approved by the institutional review board. Patient informed consent was waived. A total of 162 exophytic (2 cm or greater) renal masses in 152 patients (103 men, 49 women; mean age, 58 years; age range, 23-85 years) were included. Two radiologists independently recorded the mass size and angular interface on single-shot fast SE T2-weighted MR images. Surgical pathologic report and MR follow-up were used as reference standards. Logistic regression analysis was used to examine the usefulness of these variables for differentiating benign masses from RCCs. Diagnostic performance was analyzed by comparing values for area under receiver operating characteristic curve (A(z)). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of angular interface for diagnosing benign masses were calculated. Reader agreement was assessed with kappa-weighted statistics and intraclass correlation coefficients (ICCs). RESULTS Of 162 masses, 65 were benign, and 97 were RCCs. The sensitivity, specificity, PPV, NPV, and A(z) of angular interface for diagnosing benign masses were 78%, 100%, 100%, 87%, and 0.813, respectively. Angular interface (P < .001) was a significant predictor of benign renal mass but mass size (P = .66) was not. There was almost perfect interobserver agreement for mass size (ICC = 0.96) and angular interface (kappa = 0.91). CONCLUSION The presence of an angular interface with the renal parenchyma at single-shot fast SE T2-weighted MR imaging is a strong predictor of benignity in an exophytic renal mass 2 cm or greater in diameter with high specificity and diagnostic accuracy.

Adenomyosis: Sonohysterography with MRI Correlation

OBJECTIVE The purpose of this study was to describe the sonohysterographic features of adenomyosis with MRI correlation. CONCLUSION In this study, when the sonohysterographic findings suggested adenomyosis, MRI findings confirmed the diagnosis in 96% of cases. Myometrial cracks are, to our knowledge, a previously undescribed sonohysterographic sign of adenomyosis.

Submucosal Fibroids Becoming Endocavitary Following Uterine Artery Embolization: Risk Assessment by MRI

OBJECTIVE The purpose of our study was to assess the relationship between the endometrium and submucosal fibroids before and after uterine artery embolization (UAE). MATERIALS AND METHODS Contrast-enhanced pelvic 1.5-T MRI was performed in 49 women before and after UAE over a 2-year period. Dominant (largest diameter) fibroids in intramural, submucosal, subserosal, pedunculated subserosal, and endocavitary locations were assessed on pre- (baseline) and postembolization MRI. Size, locations of dominant fibroids relative to endometrium and serosa before and after embolization were compared. The ratio between the largest endometrial interface and the maximum dimension of the dominant submucosal fibroid (interface-dimension ratio) was determined on baseline MRI. The infarction rate for dominant fibroids was estimated after UAE. RESULTS One hundred forty dominant fibroids were identified on baseline MRI. Forty-nine (35%) were intramural, 39 (28%) were submucosal, 34 (24%) were subserosal, eight (6%) were pedunculated subserosal, and 10 (6%) were endocavitary in location on preembolization MRI. After UAE, of 39 dominant submucosal fibroids, 13 (33%) became endocavitary: complete (n = 4), partial (n = 9) on the basis of European Society of Gynaecological Endoscopy (ESGE) classification. The preembolization mean interface-dimension ratio and mean diameters for dominant fibroids that became endocavitary were significantly greater than for those that did not become endocavitary after embolization (0.65 vs 0.32, p < 0.005; 8 vs 5.4 cm, p < 0.05, respectively). All dominant submucosal fibroids showed 100% infarction after UAE. CONCLUSION Submucosal fibroids with an interface-dimension ratio of greater than 0.55 are more likely to migrate into the endometrial cavity after UAE. The majority of these are expelled spontaneously without significant symptoms. Rarely, submucosal fibroids greater than 6 cm in size that become endocavitary may cause postprocedural complications requiring further intervention and medical treatment.

Spectrum of imaging findings on MRI and CT after uterine artery embolization

Uterine artery embolization (UAE) is an effective treatment for symptomatic uterine fibroids. Magnetic resonance (MR) imaging is typically employed to evaluate the uterus following UAE for fibroid infarction, size, location change, persistent enhancement, changes in adenomyosis, and uterine necrosis. Variable pattern of calcification on computed tomography (CT) can differentiate embolic particles and fibroid involution. CT following UAE may be requested because of acute pelvic pain or chest discomfort or pyrexia and/or for complications that may require treatment in acute phase. Visualization of gas in uterus and uterine vessels following UAE is an expected finding that should not be misinterpreted as a sign of infection. The MRI and CT appearances vary depending upon the time interval after UAE and success of the procedure. Radiologists should be familiar with the range of post-UAE appearances on MRI and CT to better aid clinicians in correct diagnosis and treatment. The main purpose of this pictorial review is to identify the spectrum of findings on MRI and CT performed after UAE, to illustrate UAE-associated common and uncommon MRI and CT appearances and discuss post-UAE complications that require urgent medical or surgical intervention.

Dilated cisternae chyli: a sign of uncompensated cirrhosis at MR imaging

BackgroundIn order to retrospectively determine the frequency of dilated cisterna chyli (CC) on MR images in patients with cirrhosis, and to assess its value as a simple diagnostic imaging sign of uncompensated cirrhosis.MethodsStudy population included 257 patients (149 with pathologically proved cirrhosis and 108 control subjects without the history of chronic liver diseases) who had 1.5 T MR imaging. Cirrhosis patients were divided into compensated and uncompensated groups. Three independent observers qualitatively evaluated the visibility of CC 2 mm or greater in transverse diameter, identified as a tubular structure with fluid signal intensity. CC diameters greater than 6 mm were defined as dilated. Statistical analysis was performed by Student t-test and interobserver agreement via intraclass correlation coefficient.ResultsCCs with diameter 2 mm or more were recorded in 113 of 149 (76%) cirrhotic patients and 15 of 108 (14%) control subjects (P < 0.001). Dilated CCs were significantly more frequent in uncompensated than compensated cirrhotic patients (54% vs 5%, P < 0.001). The sensitivity, specificity, accuracy, and positive predictive value of dilated CC for uncompensated cirrhosis were 54%, 98%, 80%, and 96%, respectively.ConclusionsDilated CC can be used as a simple and specific sign complimentary to other findings of uncompensated cirrhosis.

Intra-abdominal Esophageal Duplication Cysts: A Review

Esophageal duplication cysts (EDCs) are well described within the literature, normally occurring within the mediastinum. Intra-abdominal EDCs are rare and typically occur near the intra-abdominal esophagus. Herein, we describe two cases of intra-abdominal EDCs: a 60-year-old man who was incidentally found to have a retro-duodenal cystic mass and a 50-year-old woman with a cystic lesion near the body and tail of her pancreas causing left flank pain. Both patients underwent enucleation of their respective masses. Pathology revealed ciliated pseudostratified columnar epithelium with scattered mucus-secreting cells and two smooth muscle layers in the cyst wall of both patients, consistent with EDCs. Although intra-abdominal EDCs have been reported in the literature, our two cases and a review of the literature indicate that these lesions are not always adherent to or even near the intra-abdominal esophagus.

MR imaging for predicting the recurrence of pancreatic carcinoma after surgical resection

OBJECTIVE To study the relationship of characteristics of pancreatic carcinoma on MR imaging to tumor recurrence time after surgical resection. MATERIALS AND METHODS Twenty-seven patients with pancreatic carcinoma were followed up at least 2 years after surgical resection of the tumor. All patients had MR imaging within 1 month before surgery. The tumors size, signal intensity, local and vascular invasion, abdominal lymphadenopathy on MR imaging and the positive surgical margin were noted. The results from MR imaging were compared with the duration after surgery until tumor recurrence and with the positive surgical margin. RESULTS 59% of patients had various degree of extrapancreatic invasion. The tumor recurrence times were, respectively, 24+/-21 months and 26+/-29 months in patients with and without vascular invasion (P=0.79). The combination of vascular with local invasion showed a correlation to the time of tumor recurrence (r=-0.34; P<0.05). Patients with positive surgical margins had a higher local invasion score on MR imaging and a shorter recurrence time than those with negative surgical margins. The number and size of lymph nodes were not related with tumor recurrence time. CONCLUSION MR imaging was useful for predicting the recurrence of pancreatic carcinoma after surgical resection. Local invasion associated with and without vascular invasion on MR imaging was the indicator for the tumor recurrence.

Simple linear measurements of the normal liver: Interobserver agreement and correlation with hepatic volume on MRI

Estimation of liver size can be used as an index to monitor various aspects of liver disease and response to treatment1,2 Serial magnetic resonance imaging (MRI) may be used to monitor patient treatment and determine management. Midclavicular (MCL) craniocaudad (CC), or midhepatic (MHP) CC measurements have been used in ultrasound (US) to estimate liver size.4,5 These methods have been extrapolated to advanced imaging methods, including computed tomography (CT) and MRI.6–9 There are no studies correlating simple linear hepatic measurements on MRI and hepatic volume. The aim of the present study was to determine interobserver agreement for the following linear hepatic measurements: MHP CC, maximum CC to liver tip (Max CC), maximum transverse, and MHP anteroposterior (AP) dimensions. Individual liver measurements and their products

Hematocolpos secondary to acquired vaginal scarring after radiation therapy for colorectal carcinoma.

Hematocolpos in a postmenopausal woman is uncommon because most cases are due to a congenital anomaly and present during the neonatal or perimenarchal period. In older women, hematocolpos results from near or complete vaginal occlusion secondary to radiation therapy for cervical carcinoma or from scarring after surgical procedures such as cone biopsy Rarely, vaginal obstruction may be due to postmenopausal atrophy, endometriosis, or vaginitis, leading to scarring or adhesions. 1―6 Hematocolpos after radiation therapy for colorectal carcinoma is a rare clinical entity. We report an unusual case of hematocolpos secondary to acquired vaginal scarring after radiation therapy for colorectal carcinoma in a postmenopausal woman who had dyspareunia and pelvic and lower back pain. Characteristics on 3-dimensional (3D) transvaginal sonography (TVS) and magnetic resonance imaging (MRI), as well as intraoperative sonographic guidance, are described, together with current management and a review of the literature. The diagnosis of vaginal scarring and associated hematocolpos was suggested by TVS and confirmed by intraoperative sonography.

Case report: MRI diagnosis of multifocal epithelioid hemangioendothelioma of the liver

Epitheloid hemangioendothelioma (EHE) is a vascular tumor of intermediate malignancy that arises in soft tissues, liver, lung, bone, and spleen.[1] The hepatic form of multifocal EHE is a rare, less aggressive, slowly progressive tumor, with malignant cells showing dendritic and epitheloid appearances.[2] The tumor is often misdiagnosed because of its nonspecific clinical manifestations and biochemical parameters, the prolonged clinical course, and variable imaging findings. In our patient, characteristic liver contour abnormalities on dynamic contrast-enhanced MRI and histopathological confirmation with appropriate immunohistochemical markers facilitated a correct diagnosis. The only definitive treatment is surgical resection or orthotopic liver transplantation after dedicated radiological and histopathological examination.[3–5]