D. Kehagias

Hemodynamic interaction between portal vein and hepatic artery flow in small-for-size split liver transplantation.

Abstract.In split-liver transplantation, the entire portal flow is redirected through relatively small-for-size grafts. It has been postulated that excessive portal blood flow leads to graft injury. In order to elucidate the mechanisms of this injury, we studied the hemodynamic interactions between portal vein- and hepatic artery flow in an experimental model in pigs. Six whole pig liver grafts were implanted in Group 1 (n=6) and six whole liver grafts were split into right and left grafts and transplanted to Groups 2 (n=6) and 3 (n=6), respectively. The graft-to-recipient liver volume ratio was 1:1, 2:3 and 1:3 in Groups 1, 2 and 3, respectively. Portal vein- and hepatic artery flows were measured with an ultrasonic flow meter at 60,120 and 180min after graft reperfusion. Portal vein pressure was also recorded at the same time intervals. Graft function was assessed at 3,6h and 12h, and morphological changes at 12h after reperfusion. Following reperfusion, portal vein flow showed an inverse relationship to graft size, while hepatic artery flow was reduced proportionately to graft size. The difference was significant among the three groups (P<0.05). Portal vein pressure was significantly higher in group 3, compared to groups 1 and 2 (P<0.05). Hepatic artery buffer response was significantly higher in Group 3, compared to Groups 1 and 2 in relation to pre-occlusion values (P<0.05). Split-liver transplantation, when resulting in small-for-size grafts, is associated with portal hypertension, diminished arterial flow, and graft dysfunction. Arterial flow impairment appears to be related to increased portal vein flow.

Focal nodular hyperplasia: imaging findings.

Abstract Focal nodular hyperplasia is an uncommon benign hepatic tumor that continues to pose diagnostic dilemmas. Imaging techniques are of great value in diagnosis of this tumor. In this article we present the US, CT, MR imaging, scintigraphy, and angiography findings. The demonstration of a central vascular scar is very helpful. Although the radiologic features may be diagnostic, many atypical cases must be differentiated from other benign or malignant hepatic tumors. In these cases excisional biopsy and histopathologic examination are necessary to determine a definite diagnosis.

MR imaging of tuberculous vertebral osteomyelitis: pictorial review

Abstract Vertebral osteomyelitis is one of the most common manifestations of tuberculosis. Magnetic resonance imaging is considered the main imaging modality for the diagnosis, the demonstration of the extent of the disease, and follow-up studies. Vertebral destruction involving two consecutive levels with sparing of the intervertebral disc, disc herniation into the vertebral body, epidural involvement, and paraspinal abscess are the most common MRI findings suggestive of tuberculous vertebral osteomyelitis.

Abdominal retained surgical sponges: CT appearance

Abstract. Retention of surgical sponges is rare. They cause either an aseptic reaction without significant symptoms or an exudative reaction which results in early but nonspecific symptoms. Computed tomography is very useful for recognition of retained sponges. The appearance of retained sponges is widely variable. Air trapping into a surgical sponge results in the spongiform pattern which is characteristic but unfortunately uncommon. A low-density, high-density, or complex mass is found in the majority of cases, but these patterns are not specific. Sometimes, a thin high-density capsule may be seen. Rim or internal calcification is a rare finding. Finally, a radiopaque marker is not a reliable sign. Differentiation from abscess and hematoma is sometimes difficult.

CT appearance of solitary and multiple cystic and cavitary lung lesions

Abstract Cystic and cavitary lung lesions constitute a spectrum of pulmonary diseases diagnosed in both children and adults. We reviewed the CT findings of the most common cystic and cavitary lung lesions and we defined useful morphological criteria that will help

MR imaging of complex tail-gut cysts

Retrorectal-cyst hamartomas (RCH) are rare developmental tail-gut cystic tumours of the retrorectal space, which occasionally undergo malignant transformation. We describe the magnetic resonance imaging (MRI) findings in two patients with RCH and in a third patient with unclassified sarcoma arising from a RCH. The RCH were hypointense or hyperintense on T1-weighted images and hyperintense on T2-weighted images; they did not enhance and they contained multiple septations. A solid component in the periphery of one cyst was markedly hypointense on T2-weighted images in keeping with fibrous material. The sarcoma arising from the wall of the RCH enhanced and was of intermediate signal intensity on all sequences. MR may help establish the diagnosis of RCH if an unenhanced cystic tumour is discovered in the retrorectal space and it can help detect those rare cases of malignant transformation of these developmental tumours.

Liver resection with repair of major hepatic veins.

BACKGROUND Liver resections for tumors adjacent to major hepatic veins often require reconstruction of venous wall defects. We describe a new operative approach that facilitates repair of major hepatic veins during hepatectomies. METHODS In 3 cases of liver tumors, the resection line had to include partially the wall of the right hepatic vein, middle hepatic vein and left hepatic vein of the preserved liver. The procedure was carried out by employing portal triad clamping combined with extrahepatic occlusion of the hepatic veins. Venous grafts for vascular repair were harvested from the inferior mesenteric vein. RESULTS In all 3 patients, histology showed tumor-free resection margins. Follow-up of 32 to 42 months revealed no recurrence and excellent liver function. CONCLUSIONS Combination of selective hepatic vascular exclusion with venous repair techniques, facilitates extensive liver resections in patients with tumors adjacent to the major hepatic veins and maximizes preservation of healthy liver tissue.

Horseshoe kidney associated with anomalous inferior vena cava

Abstract. Horseshoe kidney associated with anomalous inferior vena cava is a rare congenital anomaly. Radiological demonstration of this combined anomaly is also uncommon, with only two cases of preisthmic inferior vena cava with horseshoe kidney in the imaging literature. We report a case of simultaneous horseshoe kidney and inferior vena cava lying anterior to the right renal moiety diagnosed by ultrasound and computed tomography.

MR appearance of pelvic hemangiopericytoma

Abstract. A case of pelvic hemangiopericytoma in a 59-year-old woman is reported. The MR imaging features are presented. The tumor was unresectable and the patient received postoperative irradiation of 4200 cGy on the pelvis. One year after diagnosis, metastasis to a lumbar vertebra was discovered and additional irradiation of 3900 cGy was applied. One year later, CT showed control of the pelvic tumor and its metastasis.

Retroperitoneal lymphangioleiomyomatosis: CT appearance

Abstract. Lymphangioleiomyomatosis is a rare disease involving the lung, lymphatic trunk and lymph nodes. Sometimes it appears in the retroperitoneum with or without subsequent development in the lungs. We present a 52-year-old woman with retroperitoneal location of the disease. We discuss the abdominal CT appearance, the cytologic and immunophenotypic features and a preoperative differential diagnosis is attempted.