Imaging Features of Adult Choledochal Cysts: a Pictorial Review

Choledochal cysts are rare congenital anomalies which are principally diagnosed by disproportional dilatation of the extrahepatic bile ducts. In addition, choledochal cysts are believed to arise from the anomalous union of the common bile duct and pancreatic duct outside the duodenal wall which is also proximal to the sphincter of the Oddi mechanism. The various types of choledochal cysts have been classified on the basis of these anomalous unions (Komi classification) and their anatomical locations (Todani classification). The multidetector computed tomography with reformatted imaging, magnetic resonance cholangiopancreatography, and an endoscopic retrograde cholangiography represent the important techniques providing the anatomical resolution and detail required to properly diagnose and classify choledochal cysts and their associated abnormal features of the biliary tree, as well as their pancreaticobile duct union. This study describes the various imaging features of a choledochal cyst in adults according to the various types of anomalous unions of the pancreaticobile duct according to Komi's classification and anatomic location according to Todani's classification. Lastly, we also review and discuss the associated abnormal findings developed in biliary systems.

Detection of Hyperechoic Inflammatory Fatty Tissue during Transabdominal Ultrasonography: Diagnostic Role in Acute Abdomen

PURPOSE: To assess the incidence and diagnostic role of hyperechoic inflammatory fatty tissue (HIFT) in transabdominal ultrasonography (TAUS) for acute abdomen. MATERIALS AND METHODS: With TAUS, we examined 98 consecutive patients (68 women, 30 men; mean age, 32 years; age range, 4-84 years) having acute abdominal pain. We examined the abdomen and pelvis by TAUS to determine the cause of acute abdomen, to check for the presence of HIFT, and to investigate whether it was easier and earlier to find the main cause and HIFT presence. We also prospectively evaluated the shape, distribution, and diagnostic role of HIFT. Final diagnoses consisted of 47 cases of acute appendicitis, 14 of enterocolitis, 13 of PID, 7 of gynecological hemoperitoneum, 5 of colonic diverticulitis, 3 of ovarian torsion, 2 of colon perforation, 2 of only presence of non-specific HIFT, 1 of mesenteric lymphadenitis, and 4 of normal. RESULTS: HIFT were seen in 67 patients (68.4%), including 44/47(93.6%) of acute appendicitis, 2/14(14.3%) of enterocolitis, 11/13(84.6%) of PID, 0/7 of hemoperitoneum, 5/5 of colonic diverticulitis, 0/3 of ovarian torsion, 2/2 of colon perforation, and 1/1 mesenteric lymphadenitis. HIFT were detected earlier than the main cause in 17/44 of acute appendicitis, 6/11 of PID, and 4/5 of colonic diverticulitis. In acute appendicitis, the shape of HIFT appeared as fat thickening along the mesoappendix in 12/44, fat thickening along the mesoappendix and the opposite side in 13/44, fat encircled appendix in 6/44, fatty mass wrapping abscess in 10/44, and diffuse intraperitoneal fat thickening in 3/44. In PID, HIFT appeared as a single fatty mass in the pelvis and lower abdomen in 6/11, wrapping pelvic abscess in 2/11, and multiple fatty masses scattered in abdomen and pelvis in 3/11. In colonic diverticulitis, all 5 cases appeared as hyperechoic hemispheric mass covering the inflamed diverticulum. CONCLUSION: HIFT are a usual US finding in patients with acute abdomen, particularly on abdominal and pelvic inflammatory conditions, and they appear with characteristic shape and location in each disease. Therefore, earlier detection of HIFT using TAUS may be useful to make differential diagnosis and find complication in acute abdomen.

Focal Nodular Hyperplasia with Retraction of Liver Capsule: A Case Report

Focal nodular hyperplasia (FNH) is characterized by the presence a central scar with radiating fibrous septa. Our case had a capsular retraction, which was the result of an extension of the central scar to the surface. In addition, a hypointense scar on the T2-weighted image and a minimal enhancing central scar on the enhanced T1-weighted image, which was due to dense, sclerotic collagenous tissue, were observed. We report the first case of FNH with a capsular retraction.

Von Hippel-Lindau disease: A Case Report

Von Hippel-Lindau disease is an autosomal dominant disorder characterized by the presence of multiple benign and malignant tumors including hemangioblastomas of the retina and central nervous system, pancreatic cysts and tumors, renal cell carcinomas, pheochromocytomas and epididymal cystadenomas. We report the radiologic findings of a case of von Hippel-Lindau disease, describing the family history.

Detection of Acute Gastrointestinal Bleeding by Intra-arterial Scintigraphy: An Experimental Study andPreliminary Clinical Experience

PURPOSE: The purpose of this animal and clinical study was to compare intra-arterial(IA) scintigraphy withangiography in the localization of gastrointestinal (GI) bleeding. MATERIALS AND METHODS: After sedation withintramuscularly administered ketamine, lower GI bleeding was induced in ten rabbits. Using inguinal cut-down, anarterial femoral 3F catheter was placed in the proximal mesenteric artery. Following abdominal incision to exposethe bowel, lower GI bleeding was caused by incising the antimesenteric border of the small bowel wall. Initialangiography was performed, and this was followed by Tc-99m pertechnetate IA scintigarphy. Tc-99m RBC IAscintigraphy involved two patients who had undergone selective mesenteric arterial catheterization for theevaluation of acute lower GI bleeding. RESULTS: Ten rabbits, bleeding at a mean rate of 0.7g/min, were studied.IA scintigraphy was superior to angiography in four cases and equal in six. The sensitivity of angiography was40%(4/10), and IA scintigraphy 80%(8/10). In one patient, Tc-99m RBC was administered directly into the superiormesenteric artery and ulcer bleeding in the transverse colon was identified. Prior to conventional angiography,the bleeding had been occult. In a second patient, in whom angiography had revealed a hypervascular mass,selective injection of Tc-99m RBC into the superior mesenteric artery revealed tumor(leiomyoma) bleeding in thejejunum. CONCLUSION: Selective IA scintigraphy was valuable for detecting intestinal bleeding, occult duringconventional studies and may be useful for detecting acute bleeding at the time of negative angiography.

Simple Bone Cyst involving Proximal Epiphysis of the Humerus: A Case Report

Simple or unicameral bone cysts are metaphyseal lesions of long bones. They usually move away from the physiswith growth to become diaphyseal in location. Involvement of the physis and epiphysis by these cystic lesions isvery rare. This paper reports a case of simple bone cyst of the proximal humerus in a 11- year -old girl which wasshown by MR imaging to extend through the physis into the epiphysis.

Preoperative Tract Dilatation for Percutaneous Nephrolithotomy

PURPOSE: The purpose of this study was to understand the principle of percutaneous nephrolithotomy(PNL), toincrease its success rate, and to base the radiologic approach on preoperative interventional tract dilatation. MATERIALS AND METHODS: Twenty-six patients(male, 19, female, 7) with staghorn or pelviocalyceal calculi who hadundergone PNL were included in this study. After percutaneous nephrostomy(PCN) was performed in each patient, thetract was dilated to 30F with Amplatz dilators using coaxial techniques or a 30F, 10cm high-pressure tractdilatation balloon. One day before the calculi were fragmented and removed by PNL, a 30F Amplatz sheath wasinserted under local anesthesia. The time required for tract dilatation, complications, and surgery was analyzed. RESULTS: Percutaneous tract dilatation were successful in all patients, and forceps, a nephrolithotome and anephroscope were successfully introduced into the pelvocalyceal system. The average procedure time was 19.5minutes ; a double J stent was replaced in the pelvocalyceal system of 13 of 26 patients (50%) ; because ofimproper catheter direction or/and bleeding, the Amplatz sheath was replaced in three. After PNL, complicationsinvolving renal hematoma occurred in one patient. This did not affect the patient's prognosis, however. CONCLUSION:Owing to its short procedure time and low complication rate, interventional preoperative tract dilatation forPNL is thought to be an effective technique for patients with staghorn or pelvocalceal calculi.

Large Deep Infarcts found in Proximal Middle Cerebral Artery Steno-occlusive Disease: MRI and AngiographicFindings

PURPOSE: To determine the nature of large deep -seated infarcts without cortical infarct in patients withsteno-occlusive disease of the proximal middle cerebral artery(MCA) using magnetic resonance images(MRI) andangiography. MATERIALS AND METHODS: By means of MRI and MR angiography(MRA), we examined 24 patients with largedeep cerebral infarctions(>3cm in size) involving the basal ganglia, corona radiata and/or centrum semiovale, aswell as steno-occlusive lesion of the proximal MCA. According to location, infarctions were classified into fivegroups, as follows: Group 1: basal ganlgia and corona radiata; 2: basal ganglia, corona radiata and centrumsemiovale; 3: corona radiata and centrum semiovale; 4: corona radiata; 5: basal ganglia only. We evaluated thetopography of the lesions and correlated the results with the findings of angiography(all 24 MRA; the 13:conventional angiography). Involvement of the head of the caudate nucleus and the internal capsule were alsoevaluated. RESULTS: Fifteen of 24 cases(63%) were assigned to group 1 (4 proximal MCA(M1) occlusion and 11stenosis), and five of 24 (21%) with M1 occlusions to group 2. Group 3 comprised only one case with M1 occlusion.Two cases with both occlusion and stenosis were included in group 4, and only one case-with M1 stenosis-in group5. Infarctions at the caudate nucleus were seen in five cases, and at the internal capsule in two. On conventionalangiography(13 cases) cortical branches of the MCA were delineated through the leptomeningeal collaterals ofanterior or posterior cerebral arteries. CONCLUSION: Most large deep cerebral infarctions found in proximal MCAdiseases are thought to extend cephalad to the corona radiata. When large deep-seated infarctions with proximalMCA occlusion is observed more frequently than stenosis.

Efficacy of Renal Artery Embolization with 50% Acetic Acid in Rabbits, and Pathologic Findings

PURPOSE: To evaluate the embolic effect and pathologic change in the kidney after infusion of 50% acetic acidin the renal artery. MATERIALS AND METHODS: Five kidneys were embolized with 50% acetic acid mixed with saline(group A) and five were embolized with 50% acetic acid mixed with contrast medium (group B). Four rabbits(2 fromgroup A and 2 from group B) were sacrificed during the first day and the remaining six, 28 days afterembolization. To determine the effect of embolization and pathologic findings, the two groups were compared. RESULTS: Complete occlusion of the renal artery was observed in both groups; histologic findings indicatingtubular necrosis and blood clots within the renal artery were noted one day after embolization. After four weeks,complete necrosis of the renal arterial wall and tubular cells had occurred. The procedures required forembolization were easier in group B because the extent of embolization could be controlled by fluoroscopy. CONCLUSION: At 50% dilution after mixing with contrast medium, the embolie effect of acetic acid isperfect;because the embolic material is visualised the procedure was easier to control than embolization withalcohol. acetic acid can, threrfore, be used as an effective embolic agent in renal artery embolization.