Software for hepatic vessel classification: feasibility study for virtual surgery.

PURPOSE: The detection and classification of hepatic vessels in diagnostic images are essential for hepatic pre-surgery planning. Our team has developed a tool for classification, analysis, and 3D reconstruction of the hepatic and portal systems. METHODS: Our software first extracts a graphic representation of a set of connected voxels, representing both systems. It then calculates two binary volumes representing the main part of the two venous systems. Finally, it combines these results to obtain the correct vessel classification. RESULTS: Segmentation steps are semi-automatic and require about 40 min to complete. Schematization and classification steps are automatic and require about 17 min for results. CONCLUSION: The software provides a correct and detailed reconstruction even where pathologies have caused morphological and geometrical variations in the vessels. The time required for the entire procedure is compatible with clinical requirements, providing an efficient tool for diagnosis and surgical planning.

[Endoscopic, percutaneous and laparoscopic treatment for acute biliary pancreatitis]. / Traitement endoscopique, percutané et coelioscopique des pancréatites aiguës biliaires.

AIM OF THE STUDY: The aim of this study is to evaluate the results of acute gallstone pancreatitis treatment and to discuss indications in relation with the different forms of the disease. MATERIAL AND METHOD: From january 1992 to june 2001, 137 patients have been treated for an acute gallstone pancreatitis. Diagnostic criteria were given by the history, clinical examination, biochemical and radiological findings. After exclusion of patients with a systemic disease, a group of 129 patients have been enrolled in a treatment regimen with an endoscopic retrograde cholangiopancreatography (ERCP) and eventual sphincterotomy, a percutaneous US-guided cholecystostomy (PC) when necessary and an elective laparoscopic cholecystectomy. RESULTS: ERCP has been successfully performed in 121/129 patients. A PC has been performed in 5/8 patients of the failed endoscopic procedure and in 14 with acute cholecystitis. Retrograde and percutaneous cholangiographies showed main bile duct stones in 89 patients, a dilatation of the main bile duct without stones in 26 patients and a negative finding in 6 patients. An endoscopic sphincterotomy has been performed in 117 patients. A laparoscopic cholecystectomy has been performed in 118 patients. Mortality and morbidity rates were 1.6 and 10.3%, respectively. CONCLUSION: ERCP and sphincterotomy seem to be indicated in all patients observed during the first 72 hours. Endoscopic treatment and percutaneous procedure make it possible to reduce at a very low rate the cases with an unfavourable course of the disease. A definitive treatment may then be performed by the way of a laparoscopic cholecystectomy.

Influence of the boundary thermal conditions on the air change efficiency indexes.

The influence of a thermal heterogeneity boundary conditions on the air change efficiency (ACE) of a mechanical ventilation system in a test room was experimentally evaluated by means of the "step-down" tracer gas technique in 24 different experimental conditions. The experiments were performed under isothermal condition, varying the air supply temperature with respect to the walls and varying the surface temperature of a wall with respect to the other walls and the supply air, simulating both heating and cooling situations. Changing the position of the outlet grid two different configurations of the ventilation system were tested. The nominal supply air velocity varied between 0.04 and 0.11 m/s, corresponding to a range from 1 to 3 ach, and the temperature differences varied from 0 to 5 degrees C. Results are reported in terms of air change efficiency indexes, both local and global. The global air change efficiency (ACE), values are presented as a function of the Archimedes number (Ar), whose values were in the range 0 to 181. The reported results suggest that the Ar number may be used to organize the ACE values when in the presence of thermal heterogeneity, both in the external envelope and in the supplied air. The obtained results show that there is a logarithmic relation between Ar and ACE. In particular, for both ventilation strategies tested, the increase of the absolute value of Ar leads to an increase of ACE when the supply air is warmer than the walls, and to a decrease of ACE when the supply air is colder than the walls. Under isothermal conditions the Reynolds number (Re) fairly correlates the experimental results.

Vater's papilla and periampullary area villous adenoma: personal experience about nine cases and review of the literature.

Villous tumor of the duodenum is a rare disease. The authors report their personal experience from 1987 to 1993 with nine cases of duodenal villous tumors. The treatment was pancreatoduodenectomy in four cases, segmental resection of the duodenum in two cases and submucosal excision in three cases. The authors review the literature of the last 15 years in which only 241 cases of duodenal villous tumors are reported; in this review the clinical, diagnostic and therapeutic characteristics of the disease are analyzed. This malignancy presents peculiar characteristics for histologic diagnosis and pathology classification. For this reason, even surgical treatment deserves careful reflection to guarantee a curative procedure and to formulate a positive prognosis.

[Reconstructive techniques in malignant tumors of the sternum]. / Tecniche ricostruttive nei tumori maligni dello sterno.

The Authors analyze the main surgical techniques for the treatment of malignant sternal neoplasms. Their experience in two cases of sternal chondrosarcoma is reported. Techniques of reconstruction of the chest wall as well as long-term results are described.

[Esophageal prostheses by the endoscopic route (technics and results)]. / Le protesi esofagee per via endoscopica (tecnica e risultati).

The Authors reviewed their experience with palliative intubation for esophageal cancer. They have treated with endoscopic endoprostheses 197 patients with malignant strictures of the esophagus and/or cardias. Results and complications ore reported.

[Conservative treatment of stenosis of the pylorus. A proposal of a technic and results]. / Trattamento conservativo delle stenosi del piloro. Proposte di technica e risultati.

The authors reported 6 cases of pyloric stenosis treated endoscopically by a new technic. Results have been good in all cases.

Esophagectomy and esophageal replacement by gastric pull-through procedure.

The gastric pull-through procedure is a relatively new surgical technique for carcinomas of the hypopharynx and cervical esophagus and benign diffuse stricture of the thoracic esophagus, that require total esophagectomy. This technique is original both in the exeretic and reconstructive phase: total esophagectomy is performed by blunt dissection; thoracotomy and pleural damage are avoided. The basic principle of the operation is the gastric transposition into the neck through the posterior mediastenum and a pharyngogastric or esophagogastric anastomosis, according to the type of disease. Fourteen of our cases who underwent a gastric pull-through are presented and discussed.

Carcinoembryonic antigen and cancer: a comparative study.

The sera of 212 patients with malignant and non-malignant diseases have been radioimmunoassayed for the presence of the carcinoembryonic antigen (CEA) using 3 different kits produced of Hoffman La Roche, Switzerland (RCK), BY Sorin-IRE, Italy and Belgium (SCK), and by the Istituto Sieroterapico Milanese, Italy (ICK). In the presence of endodermically-derived system carcinomas, the RCK gave more positive results (72.6%) than did the SCK (63.1%) or ICK (56.2%). With regard to other carcinomas, ICK (50.0%) and SCK (47.1%) gave better results than did RCK (30.6%). The results are discussed in terms of clinical usefulness of the CEA assay and as regards reproducibility, procedural advantages, and economical cost of each kit. It is concluded that the CEA assay cannot be used for the diagnosis of gastrointestinal cancers, although it is useful as a measure of "cancerosity" for prognostic purposes. In this sense the double antibody method employed by SCK and ICK is clinically more advantageous than is the perchloric acid extraction-zirconyl phosphate gel precipitation method of RCK.