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M Ciocca

Publications and source records attributed to M Ciocca.

53 records · Page 3Linked to original sources

[Treatment technic and clinical dosimetry in whole-body irradiation].

At the Istituto Nazionale Tumori, Milan, total-body irradiation (TBI) is delivered by a 15 MV linear accelerator, with two lateral opposed beams. Maximum build-up at the skin is achieved by lateral slabs of perspex 3 cm thick. Attenuation filters or bolus are used for dose compensation, or reduction, to the head and lungs. The dose delivered to clinically relevant anatomic regions is determined by "in vivo" dosimetry. For this purpose, calibrated diodes are employed, which are positioned at the entrance and at the exit of the beams. "In vivo" dosimetry data show our TBI technique to allow an homogeneous irradiation of all body areas, with maximum deviation of the mean dose value from reference point dose of -11% in the posterior abdomen, at the spinal cord shielded by arms.

Humans↗

Anti-delta antibody in various HBsAg positive Argentine populations.

One thousand five hundred and seventeen HBsAg carriers from different cities of Argentina were studied for the presence of anti-Delta antibody (anti-HDV) in their sera. One thousand one hundred and sixty-eight were volunteer blood donors and 349 were patients with liver disease. Different liver diseases were diagnosed by clinical, biochemical, and histological parameters. Among blood donors, 16 (1.4%) were positive for the antibody and none was Delta-antigen positive. In 130 patients with acute hepatitis, one (0.77%) was positive for anti-HDV, as well as three (2.22%) out of 135 patients with chronic active hepatitis (CAH), and three (5.77%) out of 52 patients with cirrhosis (C). No anti-HDV positive was found among seven fulminant hepatitis (FH) cases. The presence of HBeAg and anti-HBe was studied in anti-HDV positive sera; eleven (69%) volunteer blood donors were anti-HBe positive, and five (31%) were HBeAg positive. HBeAg was positive in the three CAH cases, and in one out of three C Cases with anti-HDV positive. Hepatitis Delta antigen was also positive in the hepatocytic nuclei in the three patients with C and two of the three CAH cases. The present results show that Delta infection is rare among blood donors in Argentina. A small variation without statistical significance could be found within different geographical areas. Among patients with HBsAg related liver disease, the presence of HDV markers was also low.

Adolescent↗

[Liver ultrastructure in congenital atresia of the extrahepatic bile ducts].

Seven patients with diagnosis of biliary atresia (BA) and two patients with neonatal hepatitis were studied by electron microscopy. In all patients the diagnosis was done by clinical examinations, laboratory assays, histological studies by punch or surgical biopsies and or surgical examinations combined with intraoperatory cholangiography. The ultrastructural alterations found in both groups of patients were essentially similar to those described in other forms of cholestasis. In patients suffering from biliary atresia the main features found at hepatocytic livel were: Finely granular deposits of electron dense substance sometimes conforming lamellar structures; 2) Some increase and vesiculation of smooth endoplasmic reticulum membranes; 3) Reductions in number and length of sinusoidal microvilli; in some areas was also detected basal membrane and an increase in the amount of collagen fibers in the space of Disse; 4) Marked bile canaliculi dilatations with reduction of microvilli and thickening of the pericanalicular surrounding area, some canaliculi were constitued by several hepatocytes. Ductules were found in only 3 cases with the following alterations: 1) Intracytoplasmic electron dense deposits of granular material without limiting membranes; 2) A marked increase in the number of microfilaments mainly located in the apical portion of the cell or in the vicinity of the nuclei; 3) Inflammatory cells in the duct epithelium or in direct contact with the hepatocytes. The ultrastructural findings in the two cases of neonatal hepatitis (NH) resembled those described in the biliary atresia.(ABSTRACT TRUNCATED AT 250 WORDS)

Bile Ducts↗

[Rectal tonometry in the differential diagnosis of constipation in pediatrics].

Based on the difficulties regarding the clinical, radiological, and histological diagnosis of colonic aganglionosis, we resorted the motility studies. Sixty-two children (15 days-10 years of age) were studied by means of rectal motility without knowing the results of the other auxilary methods. We obtained a clear difference between aganglionic and other group formed by constipated functional or psicogenic. We conclude that rectal motility studies have the advantage of being rapid and non-aggressive, besides avoiding rectal biopsy.

Child↗

Quality control by portal film analysis in radiotherapy for prostate cancer: a comparison between two different institutions and treatment techniques.

AIMS AND BACKGROUND: Accuracy and reproducibility of patient setup during radiotherapy for prostate cancer were investigated in two different Institutions (A and B), within their Quality Assurance programs. The purpose of the study was to evaluate and compare setup accuracy and reproducibility in Institutions A and B, which adopt different patient positioning and treatment techniques for prostate irradiation. MATERIALS AND METHODS: A retrospective analysis of portal localization films taken during the treatment course was performed: 30 and 21 patients in Institutes A and B, respectively, entered the study. In Institute A, patients were treated in a prone position, utilizing an individualized immobilization cast (either an alpha cradle or a heat and vacuum-formed cellulose acetate cast) with an open table top and individual abdominal wall compressor to minimize small bowel irradiation; a 5-field conformal technique was used. In Institute B, patients were treated in a supine position without any immobilization device; a 6-field BEV-based technique (conformal only for patients treated with a radical aim) was adopted. A total of 598 portal films (420 from Institute A and 178 from Institute B) were analyzed. The mean number of films per patient was 12 (range, 4-29). Systematic and random setup errors were estimated utilizing the statistical method suggested by Bijhold et al. (1992). RESULTS: When patients with a mean (systematic) error larger than 5, 8 and 10 mm in craniocaudal, lateral and posterior-anterior directions, respectively, were compared, no statistically significant difference between the two groups was observed. Similarly, when comparing portal films, a significant difference (P <0.01) appeared only in the craniocaudal direction (errors > 5 mm: Institute A = 24%; Institute B = 11%). In both Institutes, the SD of random and systematic error distribution ranged from 1.8 to 4.2 mm, with a small prevalence of systematic errors. Only for craniocaudal shifts in Institute A was the random error larger than the systematic error, and it was significantly worse than in Institute B (1 SD, 4.2 mm in Institute A vs 1.8 mm in Institute B). CONCLUSIONS: Setup errors observed in Institutes A and B were similar and in accord with data reported in the literature. In Institute B, satisfactory geometrical treatment quality was achieved without patient immobilization. In Institute A, the goal of minimizing small bowel irradiation and prostate motion through the aforementioned technique, which makes patient position less comfortable, did not seem to considerably increase daily setup uncertainty.

Aged↗