[Documentation management: from theory to practice]. / La gestion documentaire: de la théorie à la pratique.

The management of the documentation is one of the key points regarding the efficacy and the performance of the quality management of health centres. It offers to all professionals the possibility to be informed on the procedures in use, leading to a pool of documents for improvement of organisations and for securing the critical steps of the patient management. In this paper, we will describe the optimal organisation of the documentation according to Haute autorité de santé (HAS) and ISO recommendations, then we will discuss in concrete terms the potential methods usable for the production of a tool well adapted to our routine practice, in order to achieve the objectives for security.

[Study of a new commercial film for high energy photon dosimetry]. / Etude d'un film récemment commercialisé pour la dosimétrie des faisceaux de photons de haute énergie.

Dosimetric properties of a new film, the Extended Dose Range-EDR2, manufactured by Kodak, have been studied. We have established the response of the film versus dose and compared it with that of X-OMAT V films. We found a linear response with dose, for the range from 0.5 to 4 Gy. No dependence of this curve with beam quality and with depth is observed. EDR2 films are useful for dosimetric study of high-energy photon beam, especially when high dose gradient occurs such as for Intensity Modulated Radiotherapy Treatment.

Radiotherapy with high dose rate brachytherapy boost and concomitant chemotherapy for Stages IIB and III esophageal carcinoma: results of a pilot study.

PURPOSE: Radiotherapy (RT) and concomitant chemotherapy (CT) is the standard treatment for non resectable esophageal cancer. Usual total radiation dose is 50 Gy. In order to enhance local control rate a Phase II study was initiated to evaluate the feasibility of a combined treatment with an external radiation dose of 60 Gy and three cycles of concomitant CT, using the three main active drugs (CDDP, 5 FU and MMC), followed by a high dose rate (HDR) brachytherapy delivering 10 Gy. METHODS AND MATERIALS: Fifty-three patients, 48 men and 5 women, were entered in this study. Stages were evaluated with CT scan and with endoscopic sonography. Fifteen were Stage IIB, 38 Stage III. Treatment consisted of conventional fractionated RT to a total dose of 60 Gy delivered with 2 Gy per fraction, one fraction per day and five fractions per week. The CT regimen was a combination of Cisplatinum (CDDP) 20 mg/m2 and 5 Fluorouracil (5FU) 600 mg/m2 continuous infusion, from days 1-4 Mitomycin C (MMC) was given at 6 mg/m2 on day 1. Three cycles were administered on days 1, 22, and 43. Brachytherapy was delivered one week after the end of external radiation therapy. RESULTS: Full radiation therapy dose was delivered for 94% of the patients. CT compliance, evaluated on the mean relative dose-intensity was 85% for CDDP, 81% for 5FU and 51% for MMC. Overall grade 3 and 4 WHO toxicity rates were 23% and 7%, respectively. Haematologic toxicity was the most limiting factor. One patient died from treatment toxicity. Local control rate at one year was 74%. Three-year actuarial survival rate was 27%. Distant metastasis was the main cause of treatment failure. Swallowing score was good for 75% of the patients. Stage, performance status and weight loss were prognostic factors. CONCLUSION: This regimen with high dose RT, HDR brachytherapy and concomitant CT is feasible; however, a high level of haematologic toxicity was observed with the CDDP, 5FU and MMC regimen. Despite a poor compliance with CT, treatment results are very encouraging for patients with locally advanced disease.

Polarity effect for various ionization chambers with multiple irradiation conditions in electron beams.

The effect of reversing the voltage polarity applied to an ionization chamber has been investigated in electron beams for several types of chambers and several irradiation conditions. It has been found that differences in readings can be significant for cylindrical chambers (about 10%) as well as for plane parallel chambers (20%). The effect is larger for large field sizes than small ones. It generally includes an appreciable stem and cable effect. Differences in readings with both polarities are related to the energy distribution of the electron beam and are greater for lower electron energies than higher. Polarity effect and charge deposit within the chamber wall material appear to be closely connected. This charge deposit, expressed as a proportion of the total collected charge, can be directly derived from double polarities measurements. Careful investigation of the effect should be made to avoid significant error (over 5%) in the determination of the absorbed dose.

Eye sparing in high energy X ray beams.

Treatment of cancer of the antrum and nasopharynx often includes the radiation of tissues close to an uninvolved eye. One treatment method consists of using an anterior high energy X ray beam directed to the tumor through the eye. To maintain a high dose adjacent to and behind the eye while reducing the entrance dose to the eye, build-up material is placed on the skin and a tunnel cut through to the eye. When the build-up material is tissue-like, the tunnel can be several centimeters in height and scattered radiation from the tunnel walls will largely offset the build-up properties of the beam. Using higher density build-up material, the dose to the superficial layers of the eye can be reduced almost to the limit set by the open beam characteristics. This technique has been used successfully for 8 years.

Utilization of a high energy photon beam for whole body irradiation.

Use of a high energy linear accelerator (giving high dose rates) for whole body irradiation is recommended because (a) there is a shorter treatment time compared with other techniques using orthovoltage or 60Co irradiation; and (b) there is more comfort for the patient, who does not have to turn over to receive an acceptably uniform dose. Dosimetry indicates that the usual data is not applicable for such treatments given at large distances from the source. A method of dosage calculation at large distances was checked by using TLD dosimetry in a Rando phantom.

[Use of photogrammetry for taking body contours in radiotherapy]. / Emploi de la photogrammétrie pour la prise des contours corporels en radiothérapie

A photogrammetric method for taking outline of patients in radiotherapy is described in details. Using only one couple of photographs, this fast and very precise process may restitute a great deal of transversal or longitudinal cross-sections, even after a long time because photographic stocking of information. An automatic numeric lecture of the outline may directly enter a computer for dosimetry.