Jae Mun Lee

Intestinal infarction secondary to mesenteric venous thrombosis: CT-pathologic correlation.

We reviewed CT of four patients with surgically proved bowel infarction secondary to superior mesenteric vein (SMV) thrombosis. Pathologic correlation was available in all patients. Three patients had thrombus in both portal vein and proximal SMV and the remaining patient had thrombus that was seen only in the peripheral branches of the SMV. Contrast-enhanced CT showed a segmental distribution of marked concentric bowel wall thickening in all four patients. Two patients also showed zones of different attenuation in the bowel wall, which were caused by varying degrees of edema and hemorrhage in the submucosa. Dense peripheral enhancement of the bowel wall was present in one patient. Other CT findings included ascites and mesenteric changes such as edema and vascular engorgement. The combination of thrombus in the SMV with bowel wall thickening strongly suggests bowel infarction and, therefore, warrants initiation of appropriate therapy.

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.

Effect of microbubble contrast agent during high intensity focused ultrasound ablation on rabbit liver in vivo.

OBJECTIVE To evaluate the effect of a microbubble contrast agent (SonoVue) during HIFU ablation of a rabbit liver. MATERIALS AND METHODS HIFU ablations (intensity of 400W/cm(2) for 4s, six times, with a 5s interval between exposures) were performed upon 16 in vivo rabbit livers before and after intravenous injection of a microbubble contrast agent (0.8ml). A Wilcoxon signed rank test was used to compare mean ablation volume and time required to tissue ablation on real-time US. Shape of ablation and pattern of coagulative necrosis were analyzed by Fishers exact test. RESULTS The volume of coagulative necrosis was significantly larger in the combination microbubble and HIFU group than in the HIFU alone group (P<0.05). Also, time to reach ablation was shorter in the combination microbubble and HIFU group than in the HIFU alone group (P<0.05). When analyzing the shape of tissue ablation, a pyramidal shape was more prevalently in the HIFU alone group compared to the combination microbubble and HIFU group (P<0.05). Following an analysis of the pattern of coagulative necrosis, non-cavitary necrosis was found in ten and cavitary necrosis in six of the samples in the combination microbubble and HIFU group. Conversely, non-cavitary necrosis occurred in all 16 samples in the HIFU alone group (P<0.05). CONCLUSION HIFU of in vivo rabbit livers with a microbubble contrast agent produced larger zones of ablation and more cavitary tissue necrosis than without the use of a microbubble contrast agent. Microbubble contrast agents may be useful in tissue ablation by enhancing the treatment effect of HIFU.

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.

The sternalis muscles: incidence and imaging findings on MDCT.

Objective We studied the incidence and appearance of the sternalis muscles on multidetector computed tomography (MDCT) to permit the differentiation of the sternalis from significant pathologic condition. Methods We retrospectively evaluated consecutive contrast-enhanced 16 row MDCT scans of the chest obtained in 1387 Korean patients (790 males and 597 females) between September 2003 and January 2005. All computed tomography scans were obtained in the supine position. Age ranges were 16 to 87 years and average was 59.2 years. Imaging analysis was based upon distribution (unilateral or bilateral, size, shape, and location). Statistical differences were evaluated by χ2 tests and Independent Samples t tests. Results The sternalis muscle was present in 86 (6.2%) of 1387 patients. This muscle was more common in female (44 of 597, 7.3%) than in male (42 of 790, 5.3%) patients, but statistical significance was not noted (P=0.058). Twenty-three patients showed bilateral sternalis muscles. Among 63 patients with unilateral sternalis muscles, 28 patients showed left sternalis muscles and 35 patients showed right sternalis muscles. Unilateral distribution was more common. The height, AP diameter, and width of the sternalis muscle were not significantly different between unilateral and bilateral muscles (P=0.182, 0.911, and 0.114, respectively). The height and AP diameter showed no significant difference between male and female (P=0.470, 0.329, respectively) patients, but the width was wider in male (P<0.001) patients. All sternalis muscles showed flat appearance, except for 1 case. The sternalis muscles were located longitudinally in parasternal position in all cases. Conclusions The sternalis muscle is an unusual normal variant of the chest wall musculature running parallel to the sternum with various sizes and most sternalis muscles are flat on MDCT. Unilateral distribution is more common, and the size of muscle is larger in males. Its incidence is 6.2% in Korean population. Radiologists should be familiar with the image findings of the sternalis muscle to avoid any confusing pathologic lesions and facilitate its clinical use such as flap.

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.

Utility of catheter-assisted Guglielmi detachable coiling in the treatment of wide-necked aneurysms

SummaryBackground. Catheter-assisted Guglielmi detachable coiling (CAGDC) is a technical option that was developed to allow the endovascular treatment of wide-necked aneurysms. We report upon our experiences of the CAGDC in treating aneurysms with an assessment of its efficacy and safety. Methods. The effect of CAGDC of wide-necked aneurysms was retrospectively evaluated in 10 patients (5 females, 5 males, mean age 56, range 40–76 yrs) who underwent the procedure. Findings. All the aneurysms were successfully embolized with CAGDC. Eight patients presented with SAH from an acutely ruptured aneurysm. Six patients were available for an angiographic follow up (mean: 10.3 months, range: 6–12 months). At the angiographic follow-up, all the aneurysms were stable and occluded (3 aneurysms with complete and 3 with near complete packing of the sac and neck). Complications directly related to the procedure were encountered in two patients (one coil migration, one thrombo-embolism). Three patients died as a result of complication of subarachnoid hemorrhage. Conclusion. CAGDC is a viable option for the treatment of wide neck aneurysms prior to balloon (or stent) assisted coil embolization.

Utility of the resistance index ratio in differentiating obstructive from nonobstructive hydronephrosis in children

We assessed the utility of the resistance index ratio (RIR) in distinguishing between obstructive and nonobstructive upper urinary tract dilatation in children.

Breast MRI findings after modified radical mastectomy and transverse rectus abdominis myocutaneous flap in patients with breast cancer

To evaluate the MRI findings in breast cancer patients who had undergone a modified radical mastectomy (MRM) and a transverse rectus abdominis myocutaneous (TRAM) flap.

Renal artery embolization controls intractable pain in a patient with polycystic kidney disease

A 65-year-old man with adult polycystic kidney disease (APKD) and chronic renal failure suffered from intractable abdominal pain and distension for 2 weeks. Meperidine infusion did not alleviate his pain. However, pain and abdominal distension were successfully controlled by embolization of both renal arteries.