MR imaging features for improved diagnosis of hepatocellular carcinoma in the non-cirrhotic liver: Multi-center evaluation.

PURPOSE: To determine MR-imaging features for the differentiation between hepatocellular carcinoma (HCC) and benign hepatocellular tumors in the non-cirrhotic liver. MATERIAL AND METHODS: 107 consecutive patients without liver cirrhosis (46 male; 45 ± 14 years) who underwent liver resection due to suspicion of HCC were included in this multi-center study. The following imaging features were assessed: lesion diameter and demarcation, satellite-lesions, central-scar, capsule, fat-content, hemorrhage, vein-infiltration and signal-intensity (SI) on native T1-, T2- and dynamic-enhanced T1-weighted images (center versus periphery). In addition, contrast-media (CM) uptake in the liver specific phase was analyzed in a sub-group of 42 patients. RESULTS: Significant differences between HCC (n=55) and benign lesions (n=52) were shown for native T1-, T2- and dynamic-enhanced T1-SI, fat-content, and satellite-lesions (all, P<.05). Independent predictors for HCC were T1-hypointensity (odds-ratio, 4.81), T2-hypo-/hyperintensity (5.07), lack of central tumor-enhancement (3.36), and satellite-lesions (5.78; all P<0.05). Sensitivity and specificity of HCC was 91% and 75% respectively for two out-of four independent predictors, whereas specificity reached 98% for all four predictors. Sub-analysis, showed significant differences in liver specific CM uptake between HCC (n=18) and benign lesions (n=24; P<0.001) and revealed lack of liver specific CM uptake (odds-ratio, 2.7) as additional independent feature for diagnosis of HCC. CONCLUSION: Independent MRI features indicating HCC are T1-hypointensity, T2-hypo- or hyperintensity, lack of central tumor-enhancement, presence of satellite-lesions and lack of liver specific CM-uptake. These features may have the potential to improve the diagnosis of HCC in the non-cirrhotic liver.

Colonic transformation of ileal pouch-anal anastomosis and of the distal ileum: MRI findings.

Colonic metaplasia of the ileal reservoir in patients after ileal pouch-anal anastomosis (IPAA) is described in pathological and histochemical studies. So far, there are no reports on the imaging presentation of colonic transformation. We describe the distinctive post-operative MRI features found in a 28-year-old patient with IPAA after failed conservative treatment of chronic ulcerative colitis. These distinct MRI features of colonic transformation of ileum mimicking normal colon are important to know for radiologists reading MR examinations of patients with IPAA.

18F-FDG-PET and MRI in patients with malignancies of the liver and pancreas. Accuracy of retrospective multimodality image registration by using the CT-component of PET/CT.

PURPOSE: To evaluate the accuracy of retrospective rigid image registration and fusion between F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and magnetic resonance imaging (MRI) of the upper abdomen. PATIENTS, MATERIAL, METHODS: Image fusion of PET and MRI was performed in 30 patients with suspected malignancy of the liver or pancreas. Using a commercially available image fusion tool capable of rigid manual point-based registration, PET-Images were retrospectively registered and fused by matching eight homologous points in the 3D spoiled gradient echo (GRE) MRI sequences acquired in portal venous phase and in the CT-component of PET/CT. Two separate observers (R1, R2) assessed accuracy of image registration by determining the distances in the x-, y- and z-axis as well as the absolute distance between anatomical landmarks which differed from the landmarks chosen for registration. Quality of fusion was graded using a three point grading scale (1 poorly fused; 2 satisfactory fused; 3 correctly fused) and compared to hybrid PET/CT fusion. RESULTS: Mean time of registration per patient was less than 2 minutes. Objective registration assessment showed errors between 2.4-6.3 mm in x-axis: mean 3.6 mm (R1); 4.6 mm (R2), 2.3-9.3 mm in y-axis (mean 5.1 mm; 5.5 mm) and 3.3-12.0 mm in z-axis (mean 5.9 mm; 5.9 mm.) The mean error in absolute distance between points was 6.0-16.8 mm (mean 9.9 mm; 10.6 mm). In visual assessment, most fusions were graded to be satisfactory or correctly fused: R1, R2: grade 3, 11/30 (36.7%), 22/30 (73.3%); grade 2, 13/30 (43.3%), 8/30 (26.7%); grade 1, 6/30 (20%), 0/30 (0%). Fusions were mostly comparable to hybrid PET/CT fusions. All of the fusions were defined as diagnostically relevant by both observers. CONCLUSION: Retrospective rigid image fusion of FDG-PET and MRI of the upper abdomen using the CT-component of PET/CT for registration is feasible without adaptation in image acquisition protocols and shows sub-centimeter registration errors in most cases.

[Intrahepatic sarcoma of the follicular dendritic cells]. / Intrahepatisches Sarkom der follikulär-dendritischen Zellen.

We report an intrahepatic sarcoma of the follicular dendritic cells in a 76-year-old woman with a medical history of a hyaline-vascular type of Castleman's disease. We discuss the clinico-pathological findings, the pathogenesis and the differential diagnosis of this rare tumour entity.

[Genital elephantiasis: reconstructive treatment of penoscrotal lymphoedema with a myocutaneous M. gracilis flap. Experiences from a District Hospital in Ethiopia]. / Genitale Elephantiasis: Rekonstruktive Behandlung des penoskrotalen Lymphödems durch myokutane M. gracilis-Lappenplastik. Erfahrungen aus einem District Hospital in Athiopien.

BACKGROUND: Genital elephantiasis is an illness leading to serious functional and aesthetic as well as psychosocial impairment. Since the 19th century there have been articles describing methods for surgical ablative treatment of penoscrotal lymphoedema. However, most of these methods ignore the creation a new drainage for the lymph. We now describe a new technique using a myocutaneous M. gracilis muscle flap for the reconstruction of the soft tissue damage resulting from radical excision, thus ensuring drainage of the lymph into the deep muscle compartment of the thigh. PATIENTS AND METHOD: In the District Hospital "Mettu-Karl Hospital" in the Ethiopian rain forest region of Illubabor, during a period of 6 months the described surgical procedure was applied to 9 patients suffering from severe forms of this grotesquely disfiguring disease. Two patients presented with combined penoscrotal oedema, while the other 7 patients were suffering from isolated scrotal lymphoedema alone. All patients benefited from reconstruction with a myocutaneous M. gracilis muscle flap after radical excision of the affected tissue. All patients were evaluated after 3 and 12 months postoperatively in the presence of a translator. RESULTS: All nine patients showed a functionally and aesthetically satisfying result after 3 months without postoperative occurrence of infection. The evaluation 12 months postoperatively showed no recurrence of genitoscrotal lymphoedema. All patients reported on having regained normal ability for sexual intercourse and no occurrence of urinary tract infections since the operation. Concerning fertility, no statements could be made. A significant improvement in the quality of life was observed by the regained ability to walk and work and consequently the reintegration of the patients into their socio-economic environment. CONCLUSION: Radical excision of the affected tissue followed by transferring a functioning lymphatic drainage into the deep muscle compartment of the ipsilateral thigh using a proximally based myocutaneous gracilis muscle flap treats genital lymphoedema without recurrence. Satisfying aesthetic and functional results are achieved. The described surgical technique is still successfully being performed by two Ethiopian surgeons trained in this procedure.