A case of testicular seminoma in persistent Mullerian duct syndrome with transverse testicular ectopia.

We present a rare case of testicular seminoma in persistent Mullerian duct syndrome (PMDS) with transverse testicular ectopia (TTE). A 42-year-old man noticed scrotal swelling a few weeks earlier and underwent magnetic resonance imaging (MRI) on suspicion of testicular tumor. MRI revealed a normal left testis on the left side of the left scrotum and a heterogeneous mass on the right side within the left scrotum. No right testis was found in the right scrotum. A blind-ending tubular structure with thickened wall showed a three-layer appearance on T2-weighted imaging and extended from the prostate through the left inguinal canal to the left scrotum. Findings during surgery suggested right testicular tumor associated with right TTE. The histopathological and immunohistochemical diagnoses of the testicular tumor and blind-ending tubular structure were seminoma and persistent Mullerian duct, respectively. Testicular tumor in PMDS with TTE is rare but may possess a characteristic appearance on imaging. Proper knowledge of these diseases will allow correct preoperative diagnosis.

Pneumothorax induced by radiofrequency ablation for hepatocellular carcinoma beneath the diaphragm under real-time computed tomography-fluoroscopic guidance.

BACKGROUND: Various treatments for hepatocellular carcinoma (HCC) beneath the diaphragm have been reported. Transpulmonary radiofrequency (TPRF) ablation for HCC beneath the diaphragm has been developed as a safe treatment, but pneumothorax has been reported as the most common complication of TPRF ablation. PURPOSE: To evaluate the relationship between the incidence of pneumothorax and various variables after TPRF ablation. MATERIAL AND METHODS: Seventy-six TPRF ablation sessions for unresectable HCC were performed in 66 patients (19 women, 47 men; mean age 69.6 years) under computed tomography (CT)-fluoroscopic guidance between November 2005 and April 2009. All patients had HCC beneath the diaphragm, not visible by ultrasonography. In 62 of the 76 sessions, the number of transpulmonary approaches was one as adequate, while multiple transpulmonary approaches were performed in 14 of the 76 sessions. The rate of pneumothorax and risk factors for pneumothorax were investigated. RESULTS: Among the 76 sessions, pneumothorax was detected in 51 sessions (67.1%). Among the 14 sessions with multiple transpulmonary passages, pneumothorax was detected in 13 (92.9%), while in the 62 sessions with a single transpulmonary passage, pneumothorax occurred in 38 sessions (61.3%). Hence, the number of transpulmonary approaches was a significant factor (P=0.0232). Among 13 variables investigated for the 62 sessions with a single transpulmonary approach, the only significant factor correlated with the occurrence of pneumothorax was the length of the needle trajectory through the aerated lung (P=0.0014). The incidence of chest tube placement was 7.9%. CONCLUSION: Pneumothorax occurred frequently after TPRF ablation for HCC. The main risk factors for pneumothorax after TPRF ablation for HCC were increased length of needle trajectory through the aerated lung and multiple transpulmonary approaches in one session. Even if pneumothorax occurred, pneumothorax disappeared spontaneously or with simple treatment such as manual aspiration in most cases.

MRI features of the nested variant of urothelial carcinoma of the urinary bladder: report of four cases.

We report on four patients with the nested variant of urothelial carcinoma (NVUC) of the urinary bladder and focus on their magnetic resonance imaging (MRI) findings. MRI showed that all lesions had irregular wall thickening with little protrusion into the bladder lumen. All had extravesical invasion, and two had invaded other organs (uterus and seminal vesicle). On T2-weighted images, all tumors mainly showed relatively strong hypointensity similar to that of the muscularis propria, and in three cases there was also a thin hyperintense layer on the tumor surface, suggesting edematous mucosa. Diffusion-weighted images demonstrated different degrees of hyperintensity, which was faint in one case. Dynamic contrast-enhanced MRI was performed in two cases and both showed gradual contrast enhancement. It has been suggested that NVUC may produce unique MRI findings reflecting its pathological features. It would be useful for those who interpret bladder MRI to recognize this rare urothelial carcinoma variant.

Risk factors and clinical course of portal and/or splenic vein thrombosis after partial splenic embolization.

BACKGROUND: Although portal and/or splenic vein thrombosis after partial splenic embolization (PSE) is a well-known complication, few reports evaluating risk factors have been published. PURPOSE: To investigate risk factors and clinical course of portal and/or splenic vein thrombosis after PSE. MATERIAL AND METHODS: Sixteen patients with severe hypersplenism underwent PSE between March 2005 and April 2008. The correlation between portal and/or splenic vein thrombosis after PSE detected on multidetector row CT (MDCT) and various factors were retrospectively reviewed. Further, the clinical course of portal and/or splenic vein thrombosis after PSE was observed on follow-up MDCT. RESULTS: Splenic vein thrombosis was detected in eight patients (50%) on MDCT images taken within 9 days after PSE. In one, the thrombosis also involved the portal vein. The infarct volume was identified as a significant risk factor for portal and/or splenic vein thrombosis (P=0.046). In all but one patient, splenic vein thrombosis resolved completely or improved without anticoagulation therapy. In this patient, both portal and splenic vein thrombosis developed after PSE, and anticoagulation therapy was necessary. CONCLUSION: It is suggested that a large splenic infarct volume is a risk factor for portal and/or splenic vein thrombosis after PSE. Indications for treatment of thrombosis of the portal vein system after PSE may be limited to patients with portal vein thrombosis.

Use of N-butyl cyanoacrylate in implantation of a port-catheter system for hepatic arterial infusion chemotherapy with the fixed-catheter-tip method: is it necessary?

OBJECTIVE: The purpose of our study was to evaluate the usefulness of N-butyl cyanoacrylate (NBCA) in addition to microcoils in the percutaneous implantation of a port-catheter system for repeated hepatic arterial infusion chemotherapy with the fixed-catheter-tip method. MATERIALS AND METHODS: We retrospectively studied 166 consecutive patients with unresectable advanced liver cancer for whom a port-catheter system was percutaneously implanted with its tip fixed at the gastroduodenal artery with microcoils. In 107 patients, NBCA was also used for catheter tip fixation. We compared this group with a control cohort of 59 patients who did not receive NBCA. Outcomes, including rate of success in implantation, details of embolic agents for fixation, and occurrence of complications related to catheter placement that would prohibit continuation of chemotherapy if not corrected, were compared. RESULTS: In all, port-catheter placement was successful. However, 38 complications occurred in 32 patients. Catheter dislocation occurred in nine. Hepatic artery obstruction or severe stenosis was seen in 10. Recanalization of a once-embolized gastroduodenal artery was found in two patients. The rate of dislocation did not differ significantly between patients in whom NBCA was and those in whom it was not used. However, hepatic artery obstruction appeared at a significantly higher rate, and recanalization of a gastroduodenal artery at a significantly lower rate, in patients in whom the catheter tip was fixed with NBCA. CONCLUSION: The use of NBCA correlated with a higher rate of hepatic artery obstruction. The use of NBCA should not always be required in port-catheter implantation with the fixed-catheter-tip method.

Delayed and recurrent pneumothorax after radiofrequency ablation of lung tumors.

BACKGROUND: In daily clinical work, we often face delayed or recurrent pneumothorax after radiofrequency (RF) ablation for lung tumors, but a large study on this theme has not been done. Thus, we examined the rate of delayed or recurrent pneumothorax after RF ablation for lung tumors and the risk factors associated with its occurrence. MATERIALS AND METHODS: This retrospective study was based on 194 consecutive sessions of percutaneous RF ablation of 220 lung tumors in 68 patients performed under CT fluoroscopic guidance at a single institution. Numerous variables were analyzed to the assess risk factors for delayed or recurrent pneumothorax. RESULTS: Pneumothorax after RF ablation occurred in 82 of 194 ablation sessions (42.3%). Thirty-three of 82 sessions had either delayed pneumothorax (n = 20) or recurrent pneumothorax (n = 13). The other 49 sessions had nonprogressive pneumothorax. Only contact of the ground-glass opacity (GGO) that emerged around the ablated lesion with the pleura significantly correlated with the frequency of delayed or recurrent pneumothorax in comparisons between no pneumothorax vs delayed/recurrent pneumothorax and between nonprogressive pneumothorax vs delayed/recurrent pneumothorax. The mean (+/- SD) duration before confirmation of the presence or recurrence of pneumothorax was 24.0 +/- 66.4 h. Among the 33 sessions with delayed or recurrent pneumothorax, 4 subjects needed additional treatment. CONCLUSION: Our results indicated that delayed or recurrent pneumothorax is relatively frequently encountered after RF ablation of lung tumors. Particular care must be taken with regard to the occurrence of delayed or recurrent pneumothorax when contact of a GGO with the pleura is seen after RF ablation.

Percutaneous drainage of psoas abscess under real-time computed tomography fluoroscopic guidance.

OBJECTIVES: The goal of our study was to determine the usefulness of percutaneous abscess drainage under guidance of computed tomography (CT) fluoroscopy. MATERIALS AND METHODS: Our subjects were 21 patients (seven women, 14 men; mean age 64 years; age range 30-87 years) who had undergone percutaneous drainage of 26 psoas abscess lesions under CT fluoroscopic guidance between May 2001 and January 2008. Drainage methods involved a needle puncture, insertion of a guidewire, serial dilations, and the exchange of the needle with a drainage tube. The procedures were guided by use of a helical CT scanner that provided real-time fluoroscopic reconstruction. RESULTS: Percutaneous drainage under real-time CT fluoroscopic guidance was successfully performed in every procedure. Use of real-time CT fluoroscopy allowed rapid assessment of needle, guidewire, and catheter placement. No patient had serious complications related to the drainage procedure. The mean procedure time required to drain one lesion was 35.6 +/- 13.6 min. Mean period after the drainage procedure until complete disappearance of the abscess as confirmed by CT was 12.4 +/- 10.0 days (range 3-46 days). CONCLUSION: CT fluoroscopy is useful in achieving accurate and safe drainage of abnormal psoas fluid collections.

Development of a portable training tool for simulating visceral angiographic procedures for beginners.

The purpose of this study was to evaluate the usefulness of a tool that we developed to simulate performance of visceral angiography to train beginners in the field of splanchnic angiography. Seven residents and two fellows who were rotating within the Division of Interventional Radiology at our institution between June and August 2008 participated in the evaluation of this tool. They had no experience in performing visceral angiography as an operator. Time for selection of arterial branches arising from the celiac axis on the model was measured before and after training. After such training, the participants performed actual visceral angiography as an operator with instructors beside them. Success of the trainees in selecting visceral arterial branches was evaluated in these real-life cases. In the first test using the model, seven of nine trainees (77.8%) succeeded in selecting all required arteries, while the remaining two failed to select all required arteries. After training using the model, all trainees succeeded in selecting all required arteries just before the actual angiographic study. In the actual angiography, the catheter was successfully inserted from the femoral artery and advanced to the superior mesenteric, celiac, splenic, common hepatic, gastroduodenal, and right and left hepatic arteries by all trainees with only two exceptions. In conclusion, this tool is helpful for training beginners in visceral angiographic procedures.

Successful embolization using interlocking detachable coils for a congenital extrahepatic portosystemic venous shunt in a child.

The authors report the case of a 6-year-old boy with a congenital extrahepatic portosystemic venous shunt. He had hyperammonemia. The shunt was 18 mm in diameter and located between the inferior mesenteric vein and the left internal iliac vein. The flow in the shunt was very rapid. After decreasing blood flow by inflating a balloon catheter inserted into the left internal iliac vein from the femoral vein, a microcatheter was coaxially advanced to the shunt to embolize the shunt. Embolization was successfully performed with interlocking detachable coils and microcoils without any complication. This patient's hyperammonemia resolved soon after the procedure.