Sung Eun Rha

MR Imaging Findings of Hydrosalpinx : A Comprehensive Review

Hydrosalpinx is a common adnexal lesion that may occur either in isolation or as a component of a complex pathologic process (eg, pelvic inflammatory disease, endometriosis, fallopian tube tumor, or tubal pregnancy) that leads to distal tubal occlusion. On magnetic resonance (MR) images, hydrosalpinx appears as a fluid-filled C- or S-shaped tubular structure that arises from the upper lateral margin of the uterus. Although hydrosalpinx is most often seen on ultrasonographic images, it also may be delineated on multiplanar MR images. MR imaging also may be useful for determining the cause of a hydrosalpinx or its associated adnexal process by characterizing the nature of the contents of the dilated tube. Tubal fluid with high signal intensity on T1-weighted images is suggestive of hematosalpinx associated with endometriosis and tubal pregnancy. A thickened wall of a dilated fallopian tube that displays variable or heterogeneous signal intensity may be indicative of pyosalpinx as a component of a tubo-ovarian abscess. The presence of an enhancing solid mass within a dilated tube is suggestive of fallopian tube carcinoma, whereas enhancement of the dilated tubal wall surrounding a saclike cystic mass may be indicative of a tubal pregnancy. Understanding the pathogenesis and clinical manifestations of conditions associated with hydrosalpinx may aid in the timely diagnosis of complex adnexal masses at MR imaging, enabling avoidance of unnecessary procedures.

Gallbladder wall thickening: MR imaging and pathologic correlation with emphasis on layered pattern.

The aim of this study was to correlate MR findings of gallbladder wall thickening with pathologic findings on the basis of the layered pattern and to evaluate the diagnostic value of MR imaging in gallbladder disease. We retrospectively evaluated the source images of HASTE sequences for MR cholangiography in 144 patients with gallbladder wall thickening. The layered pattern of thickened wall was classified into four patterns. Type 1 shows two layers with a thin hypointense inner layer and thick hyperintense outer layer. Type 2 has two layers of ill-defined margin. Type 3 shows multiple hyperintense cystic spaces in the wall. Type 4 shows diffuse nodular thickening without layering. MR findings of a layered pattern of thickened gallbladder were well correlated with histopathology. Chronic cholecystitis matched to type 1, acute cholecystitis corresponded to type 2, adenomyomatosis showed type 3, and the gallbladder carcinomas showed type 4. All four layered patterns were associated with PPV of 73% or greater, sensitivity of 92% or greater and specificity of 95% or greater. Our results indicate that MR findings of gallbladder wall thickening are characteristic in each entity and correlate well with pathologic findings. The classification of the layered pattern may be valuable for interpreting thickened gallbladder wall.

CT and MRI findings of cystadenofibromas of the ovary

Abstract.The aim of this study was to assess imaging findings on CT or MR images of histologically proven ovarian cystadenofibromas. In the period 1995–2001, 32 histologically proven ovarian cystadenofibromas were identified in 28 women. Of the 32 ovarian cystadenofibromas, 16 tumors were purely cystic and the remaining 16 were complex cystic on CT or MR images. Solid components of 16 complex cystic tumors were seen as nodular (n=8) or trabecular (n=9) solid areas. One tumor had both nodular and trabecular solid components. Among 16 complex cystic tumors, 14 had thick or irregular septa; thus, half of ovarian cystadenofibromas had morphological imaging features of malignancy on CT or MR images. On histology, solid components in the cystic tumors were correlated with fibrous stromas that occasionally made a false-positive result for malignancy on imaging.

Planning Ultrasound for Percutaneous Radiofrequency Ablation to Treat Small (≤ 3 cm) Hepatocellular Carcinomas Detected on Computed Tomography or Magnetic Resonance Imaging: A Multicenter Prospective Study to Assess Factors Affecting Ultrasound Visibility

PURPOSE To assess factors affecting tumor visibility on planning ultrasound (US) for percutaneous radiofrequency (RF) ablation to treat small hepatocellular carcinomas (HCCs) primarily detected on computed tomography (CT) or magnetic resonance (MR) imaging. MATERIALS AND METHODS Patients referred for planning US for percutaneous RF ablation between September 2008 and June 2009 were prospectively enrolled from nine institutions in Korea. The first small (≤ 3 cm) single HCC or new single HCC after treatment was included. The study enrolled 898 patients (684 men and 214 women, age range 32-86 years). HCCs that were invisible on planning US were compared with visible HCCs with respect to tumor size, distance between the tumor and the diaphragm, subcapsular location, etiology of liver disease, liver cirrhosis, macronodular cirrhosis on US, ascites, Child-Pugh class, serum alpha fetoprotein (AFP) level, body mass index (BMI), previous treatments for HCC, previous chemoembolization treatments for HCC, institutions, and experience of radiologists. RESULTS Among 898 HCCs, 671 (74.7%) were visible on the planning US. In multivariate analysis, tumor size, distance between the tumor and the diaphragm, liver cirrhosis, and macronodular cirrhosis were statistically significant factors affecting US detection (each P < .05). CONCLUSIONS Smaller tumors, subphrenic location of the tumor, liver cirrhosis, and macronodular cirrhosis were independent predictors of invisible tumors on planning US.

Comprehensive reviews of the interfascial plane of the retroperitoneum: normal anatomy and pathologic entities

The retroperitoneum is conventionally divided into three distinct compartments: posterior pararenal space, anterior pararenal space, and perirenal space, bounded by the posterior parietal peritoneum, transversalis fascia, and perirenal fascia. But more recent work has demonstrated that the perirenal fascia is not made up of distinct unilaminated fascia, but a single multilaminated structure with potential space. These potential spaces are represented by retromesenteric plane, retrorenal plane, lateral conal plane, and combined fascial plane. The purpose of this review was to demonstrate embryogenesis, anatomy of interfascial plane, and spreading pathways of various pathologic entities with computed tomography imaging.

Correlation of dynamic contrast‐enhanced MRI perfusion parameters with angiogenesis and biologic aggressiveness of rectal cancer: Preliminary results

To investigate whether quantitative parameters derived from dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) are correlated with angiogenesis and biologic aggressiveness of rectal cancer.

Sonography of Various Cystic Masses of the Female Groin

The purpose of this presentation is to review the pathologic spectrum of cystic masses that may involve the female groin region, with a correlation of the lesions with their sonographic appearance.

Gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid–enhanced magnetic resonance imaging predicts the histological grade of hepatocellular carcinoma only in patients with child-pugh class a cirrhosis†

The aim of this study was to investigate the role of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd‐EOB‐DTPA)–enhanced magnetic resonance imaging (MRI) in predicting the histological grade of hepatocellular carcinoma (HCC) according to the hepatic function. Eighty‐one consecutive patients with 122 histologically proven HCCs who underwent Gd‐EOB‐DTPA–enhanced MRI before resection (45 HCCs in 42 patients) or transplantation (77 HCCs in 39 patients) were analyzed retrospectively. We calculated the relative enhancement ratios (RER), which is the ratio of the relative intensity of a tumor versus the surrounding parenchyma on hepatobiliary phase images to the relative intensity on unenhanced MRI scans. We then analyzed the correlation between the RER and the tumor differentiation grade in patients with various degrees of hepatic function. The degree of tumor enhancement, which included the precontrast relative intensity ratio (RIR), the postcontrast RIR, and the RER, for well‐differentiated (WD) HCCs was significantly higher than the degree of tumor enhancement for moderately differentiated and poorly differentiated (PD) HCCs (P = 0.001 and P = 0.001, respectively, for precontrast RIRs; P < 0.001 and P < 0.001, respectively, for postcontrast RIRs; and P = 0.01 and P = 0.001, respectively, for RERs). In a subgroup analysis based on liver function, the correlation between the histological grade and the enhancement ratio was demonstrated only in the group of patients with Child‐Pugh class A cirrhosis. The accuracy of postcontrast RIRs for predicting WD and PD HCCs was favorable; the areas under the receiver operating characteristic curves were 0.896 [95% confidence interval (CI) = 0.817‐0.974] and 0.769 (95% CI = 0.658‐0.879), respectively. In conclusion, the hepatobiliary phase of Gd‐EOB‐DTPA–enhanced MRI may help to predict the differentiation of HCCs, especially in HCC patients with Child‐Pugh class A cirrhosis before liver transplantation or resection. Liver Transpl, 2012.

Gastrointestinal leiomyoma and leiomyosarcoma : CT differentiation

PURPOSE Our goal was to evaluate CT efficacy in differentiating gastrointestinal leiomyoma and leiomyosarcoma. METHOD We retrospectively reviewed CT scans of 45 patients (21 men, 24 women, mean age 55 years) with surgically proven gastrointestinal leiomyomas (n = 21) and leiomyosarcomas (n = 24) with respect to size, contour, enhancing pattern, mesenteric fat infiltration, calcification, ulceration, regional lymphadenopathy, direct invasion, distant metastasis, and growth pattern after visual inspection by two radiologists in agreement. On the basis of these CT features, subjective diagnosis was also categorized into three groups (Group I: probably benign, Group II: probably malignant, Group III: diagnostic malignant). The results were compared with the final histopathologic diagnosis. RESULTS In addition to the features of direct invasion and distant metastasis suggesting diagnostic malignancy, the CT features favoring malignancy with statistical significance included larger size (> 5 cm), lobulated contour, heterogeneous enhancement, mesenteric fat infiltration, ulceration, regional lymphadenopathy, and exophytic growth pattern (p < 0.005). However, calcification was not significant in differentiating the two entities (p = 0.25163). A subjective analysis revealed 89% sensitivity, 85% specificity, and 87% accuracy for diagnosis of leiomyosarcoma. CONCLUSION CT features are useful in differentiating leiomyoma and leiomyosarcoma in gastrointestinal tract.

Gastroduodenal Glomus Tumors: Differentiation From Other Subepithelial Lesions Based on Dynamic Contrast-Enhanced CT Findings

OBJECTIVE The purpose of this study was to describe the CT features of gastroduodenal glomus tumors and determine the CT features differentiating glomus tumors from other subepithelial lesions. MATERIALS AND METHODS CT images of 89 pathologically proven small (≤ 5 cm) gastroduodenal glomus tumors (n = 11), gastrointestinal stromal tumors (n = 44), schwannomas (n = 15), ectopic pancreata (n = 12), and leiomyomas (n = 7) were retrospectively reviewed. For subjective analysis, location, shape, growth pattern, enhancement pattern, and presence of necrosis, calcification, and surface ulceration were analyzed. For objective analysis, the long and short diameters of the lesion, ratio of long to short diameter, thickness of the overlying layer, CT attenuation of the lesion and aorta, and lesion-to-aorta ratio in the arterial, portal venous, and equilibrium phases were measured. Among these findings, significant CT variables were determined with the chi-square, Fisher exact, and Student t tests. Receiver operating characteristic analysis was used to determine the optimal cutoff values of thickness of the overlying layer and lesion-to-aorta ratio that differentiate glomus tumor from other subepithelial lesions. RESULTS Typical location (antrum and duodenum), hemangioma-like enhancement pattern, overlying layer thickness 2.6 mm or greater, and portal venous phase lesion-to-aorta ratio 0.86 or greater were found to be significant variables for differentiating glomus tumors from other subepithelial lesions (p < 0.05). Among these CT findings, location and portal venous phase lesion-to-aorta ratio 0.86 or greater were highly sensitive findings for glomus tumor, and a hemangioma-like enhancement pattern was highly specific. All odds ratios were infinity. The odds ratio of overlying layer thickness of 2.6 mm or greater was 12.2 (95% CI, 2.9-51.8). CONCLUSION A subepithelial lesion with a lesion-to-aorta ratio less than 0.86 in the portal venous phase or not in the gastric antrum or duodenum is never a glomus tumor. On the contrary, a subepithelial lesion with hemangioma-like enhancement during dynamic CT is essentially a glomus tumor. On the basis of these CT findings, glomus tumor can be differentiated from other subepithelial lesions with high diagnostic accuracy.