[Evaluation of living donors for liver transplantation: radiology and virtual surgery]. / Evaluation des donneurs vivants pour transplantation hépatique: imagerie et chirurgie virtuelle.

PURPOSE: To propose a comprehensive imaging algorithm of living donors for liver transplantation allowing virtual presurgical planning. MATERIAL AND METHODS: Prospective CT and MRI evaluation of 20 patients selected as potential living donors for liver transplantation, between June 2001 and March 2003. For each patient, a virtual hepatectomy according to anatomical biliary and vascular variations, total liver Volume and residual liver Volume, were simulated. The imaging results were correlated to the surgical findings. RESULTS: CT and MRI demonstrated thirty-five vascular and biliary anatomical variations in 17 patients. Knowledge of these variations resulted in modification of the surgical planning in 6 cases. Four additional variations were described at surgery. The virtual graft Volumes correlated well to the surgical ones (p<0.0001). CONCLUSIONS: CT and MRI are useful for the presurgical evaluation of living donors prior to liver transplantation. Estimation of the residual liver Volume allows a good prediction of the postsurgical outcome.

[Helical CT and diagnostic evaluation of cranio-facial fibrous dysplasia]. / Scanner spiralé et bilan diagnostique de dysplasie fibreuse cranio-faciale.

PURPOSE: To evaluate the role of helical CT in the evaluation of skull abnormalities seen in fibrous dysplasia. MATERIALS AND METHODS: Prospective study on 6 cases with cranio-facial fibrous dysplasia (3 males and 3 females) aged 8 to 59 years old, evaluated with plain radiographs, helical CT and, in 1 case, MRI. Helical CT was performed in 3 cases on a CT Twin scan (Elscint), in 3 cases on a Somatom Plus scan (Siemens). Multiplanar reconstructions and 3D reconstructions were done in all cases. 4 cases had a histopathological confirmation of fibrous dysplasia lesions by bone-biopsy (3 cases) or surgical biopsy (1 case). RESULTS: The 6 cases included sclerotic form in 3 cases, cystic variety in 1 case, polyostotic variety in 1 case, mixed form in 1 case. Topographic localizations of fibrous dysplasia were skull base involvement in 1 case, multizonal skull involvement in 4 cases, maxillo-mandibulary involvement (cherubism) in 1 case. CONCLUSION: Helical CT is an optimal method to evaluate the skull lesions of fibrous dysplasia. The review of source images must always be done. 3-dimensional bone reconstructions are better to visualize the anterior cranial vault and skull base dysmorphy. Helical acquisition is a compromise in case by case between the dose of irradiation and the quality of source images.

[Spiral CT evaluation of the craniosynostoses]. / Exploration des crâniosténoses par scanner spiralé.

Craniosynostoses are defined as the premature closure of one or more sutures of the cranial bones. The resulting craniofacial deformities may be associated with neurologic complications owing to the disproportion between the growing brain and the limited content of the intracranial cavity. Plain skull radiographs are often contributive to the diagnosis. However, they may not be sufficient to detect early cases and to properly evaluate the more complex cases. Computed tomography has been proved to be more efficient in the pretherapeutic evaluation. The authors present here their results in the spiral computed tomographic evaluation of primary and syndromic craniosynostosis, based on a prospective series of 26 patients. The radiologic findings are presented. They have been found here to be similar to those previously described on sequential acquisitions. Spiral computed tomography was found to provide better information than did plain radiographs in 5 cases. The value of the helical acquisition as well as tridimensional reconstructions are discussed.

The value of computed tomography in the diagnosis of the prehepatic portal hypertension.

The dynamic computed tomography (CT) is used by the authors in a complex system of investigations. It is preceded by a diagnosis stage which determines the "normal" character of the liver and it is followed by the angiographic exploration for the cases with surgical indication. 36 patients with CT diagnosis of prehepatic portal hypertension were studied; from these patients, 24 had an angiographic confirmation and 16 of them were operated. The most valuable CT signs which have been found by the authors were: the study of the portal vein at the hilum level and in the distal parapancreatic region, the hypoplasia of the left hepatic lobe and the absence of the ascites. The other signs were considered less important, only the localization of the porto-systemic shunts being to a certain degree important for surgery. It is underlined the early age of the patients (69% are under 30 years old). The diagnosis concordance was in the studied group 100% for the positive diagnosis of the syndrome, but only 79% for the localization of the obstruction. CT is the most innocuous diagnostic procedure which obtains a maximum of data on the portal system morphology.