Two cases of pyogenic liver abscess due to Klebsiella pneumoniae in immunocompetent children

Pyogenic liver abscess (PLA) can be caused by bacteria entering the liver via the portal vein or primary bacteremia, or it can be cryptogenic. Recently, Klebsiella pneumoniae has been increasingly found as a PLA pathogen. PLA due to this bacterium often leads to formation of extrahepatic abscesses. The treatment of choice is dual therapy with insertion of percutaneous catheter drainage and antibiotic therapy. We report 2 cases of PLA due to K. pneumoniae in immunocompetent children. We successfully treated patient 1 with percutaneous catheter drainage for 18 days and 6-week course of antibiotic therapy. Patient 2 was treated with percutaneous needle aspiration and antibiotic therapy for the same period. In both patients, the PLAs showed the ultrasound-confirmed resolutions after the dual therapy.

A Case of an Omental Infarction in a Child / 대한소아소화기영양학회지

An omental infarctions is an uncommon cause of an acute abdomen and a rare entity in children. The etiology is still unclear and the symptoms mimic acute appendicitis. We recently encountered a case of a 10-year-old boy who had a previous surgical history of a manual reduction for intussusception. He complained of abdominal pain and right upper quadrant tenderness without fever or anorexia. An abdominal ultrasonography suggested an omental infarction and computed tomography confirmed the diagnosis. Conservative management was adopted with a rapid and uneventful recovery. Non-operative treatment is a safe and effective treatment of choice for omental infarction.

MR Imaging Findings of Hypertrophic Olivary Degeneration

PURPOSE: To describe the magnetic resonance (MR) imaging findings of hypertrophic olivary degeneration (HOD). MATERIALS AND METHODS: MR images of seven patients with HOD were retrospectively reviewed. Two were women and five were men, and they were aged between 48 and 65 (mean 58) years. Imaging examinations were performed with a 1.5-T unit, and the findings were used to evaluate the size and signal intensity of olivary lesions. The time interval from hemorrhagic ictus to MR imaging was between two and 30 months. Follow-up examinations were performed in two patients. RESULTS: All four patients with hemorrhages involving the central tegmental tract in the pons or midbrain showed ipsilateral HOD. Among these four, bilateral HOD was seen in one patient with hemorrhage involving the bilateral central tegmental tract, and in another with tegmental hemorrhage extending to the ipsilateral superior cerebellar peduncle. One patient with cerebellar hemorrhage involving the dentate nucleus had contralateral HOD. Two patients with multiple hemorrhages involving both the pons and cerebellum showed bilateral HOD. Axial MR images showed mild enlargement of the involved olivary nucleus, with high signal intensity on both proton density and T2 weighted images. There was no apparent enhancement on postcontrast T1-weighted images. CONCLUSION: MR imaging can clearly distinguish secondary olivary degeneration from underlying pathology involving the central tegmental tract in the pons or midbrain and cerebellum. These olivary abnormalities should not, however, be mistaken for primary medullary lesions.

Comparison of Conventional Spin Echo, Fast Spin Echo and Fast Multiplanar Spoiled Gradient Recalled Imaging for Evaluation of Focal Hepatic Lesions

PURPOSE: To compare the detectability and conspicuity of focal hepatic lesions among conventional spin echo techniqueniques and fast scanning techniqueniques in MR imaging. MATERIALS AND METHOD: 36 patients (24 men and 12 women, mean age of 54 years) with suspected liver mass on CT scan and US underwent MR imaging at 1.5 T system. Conventional spin echo T1, T2 weighted imaging, T2 weighted fast spin echo, T1 weighted fast multiplanar spoiled gradient recalled(FMPSPGR) imaging and Gd-enhanced FMPSPGR(Gd-FMPSPGR) were performed. 16 cases of hepatocellular carcinoma, 13 cases of hemangioma, 3 cases of metastasis, 3 cases of cholangiocarcinoma, and 1 case of lymphoma were included. Lesion conspicuity and number of detected hepatic masses were compared among the MR sequences. RESULTS: Overall 63 hepatic lesions were detected in 36 patients. Lesion detection' was 63(100%) with Gd-FMPSPGR, 62(98%) with non-enhanced FMPSPGR, 58(92%) with SE T2WI, 56(89%) with SE T1WI and 54 (86%)with FSE. For solid tumors, the contrast to noise ratio was greatest on Gd-FMPSPGR which was significantly higher than any other sequences. For hemangiomas it was greatest on SE T2WI and was significantly higher than SE T1WI. In the qualitative assessment, Gd-FMPSPGR was preferred for both solid mass lesion and hemangioma. FSE was inferior to SE T2WI for lesion detection and conspicuity without statistical significance. CONCLUSIONS: For the evaluation of focal hepatic lesions, breath-hold FMPSPGR with and without contrast enhancement may replace the conventional SE T1WI. Because FSE was inferior to SE T2WI when the later is used with respiratory compensation in some cases, it is difficult to replace the SE T2WI with FSE. But FSE, FMPSPGR and Gd-FMPSPGR images, when combined, may replace SE T1WI and SE T2WI.

Focal Hepatic Lesions: Dynamic Multi-slice MR Imaging

PURPOSE: To evaluate the dynamic enhancement patterns of focal hepatic lesions using breath-hold dynamic MR imaging for differential diagnosis. MATERIALS AND METHOD: Thirty three patients (24 men and 12 women, mean age of 55 years) with 56 known liver masses on CT scan and US underwent MR imaging with 1.5T. After Tl-weighted fast multiplanar spoiled gradient recalled (FMPSPGR) imaging, breath-hold FMPSPGR images were obtained at 0, 1, 3, 5, and 10 minutes after bolus injection of Gd-DTPA. The cases consisted of 16 hepatocellular carcinomas, 24 hemangiomas, 6 metastases, 3 cholangiocellular carcinomas, and 7 hepatic cysts. The dynamic enhancement patterns were evaluated on the basis of initial enhancement study and, the degree of enhancement was also levaluaied. RESULTS: Of 24 hemangiomas, most cases showed centripetal filling-in pattern of enhancement except 3 cases which showed homogeneous enhancement pattern on the early dynamic phase. All hemangiomas showed very high signal intensity which persisted to the delayed phase. The eccentric enhancement pattern was the most common type in hemangiomas (63%). Hepatocellular carcinomas had heterogeneous enhancement pattern on early and delayed phase (81, 88%) and showed diminished signal intensity on the delayed images. 14 of 16 hepatocellular carcinomas (88%) had peritumoral halo. Variable enhancement pattern was observed in metastases including progressive centripetal filling-in pattern (67%). All metastases showed prominent peritumoral halos and low signal intensity. Cholangiocellular carcinomas showed early centripetal filling-in and heterogeneous enhancement pattern on delayed phase. None of hepatic cysts showed enhancement. CONCLUSIONS: Dynamic breath-hold MR imaging with Gd enhancement allows accurate assessment of hemodynamic status of hepatic lesions and is useful in differential diagnosis of focal hepatic lerions.

Focal Hepatic Lesions: Dynamic Multi-slice MR Imaging

PURPOSE: To evaluate the dynamic enhancement patterns of focal hepatic lesions using breath-hold dynamic MR imaging for differential diagnosis. MATERIALS AND METHOD: Thirty three patients (24 men and 12 women, mean age of 55 years) with 56 known liver masses on CT scan and US underwent MR imaging with 1.5T. After Tl-weighted fast multiplanar spoiled gradient recalled (FMPSPGR) imaging, breath-hold FMPSPGR images were obtained at 0, 1, 3, 5, and 10 minutes after bolus injection of Gd-DTPA. The cases consisted of 16 hepatocellular carcinomas, 24 hemangiomas, 6 metastases, 3 cholangiocellular carcinomas, and 7 hepatic cysts. The dynamic enhancement patterns were evaluated on the basis of initial enhancement study and, the degree of enhancement was also levaluaied. RESULTS: Of 24 hemangiomas, most cases showed centripetal filling-in pattern of enhancement except 3 cases which showed homogeneous enhancement pattern on the early dynamic phase. All hemangiomas showed very high signal intensity which persisted to the delayed phase. The eccentric enhancement pattern was the most common type in hemangiomas (63%). Hepatocellular carcinomas had heterogeneous enhancement pattern on early and delayed phase (81, 88%) and showed diminished signal intensity on the delayed images. 14 of 16 hepatocellular carcinomas (88%) had peritumoral halo. Variable enhancement pattern was observed in metastases including progressive centripetal filling-in pattern (67%). All metastases showed prominent peritumoral halos and low signal intensity. Cholangiocellular carcinomas showed early centripetal filling-in and heterogeneous enhancement pattern on delayed phase. None of hepatic cysts showed enhancement. CONCLUSIONS: Dynamic breath-hold MR imaging with Gd enhancement allows accurate assessment of hemodynamic status of hepatic lesions and is useful in differential diagnosis of focal hepatic lerions.