Publications (5)20.27 Total impact
-
Article: A modified 60C teletherapy unit for total body irradiation.
[show abstract] [hide abstract]
ABSTRACT: A modified teletherapy unit to achieve total body irradiation with a vertical beam in a conventional treatment room. A standard 60C teletherapy unit has been modified to achieve total body irradiation with a vertical beam in a conventional treatment room. Patients are treated in prone and supine positions. Removal of the adjustable collimator assembly of this standard machine provides a circular field of 196 cm in diameter at 167 cm from the source. Second, the machine has been elevated by about 50 cm on a metallic base to enlarge irradiation field to obtain 248 cm in diameter at 210 cm from the source, and to encompass tall patients under better conditions. A special lead conical beam flattening filter, 10-mm thick at the center, was designed to compensate the spatial inhomogeneity of the beam. An instantaneous dose rate of 6.10(-2) Gy/min is attained at the L4 level (midplane) in an average 20-cm thick patient with a source activity of 5099 RHM (air kerma rate of 44.8 Gy.h-1.m2). Between February 2, 1984 and December 27, 1990, 244 total body irradiations were performed either by single dose (n = 69, 10 Gy were given to midplane at L4 level in about 6 to 8 h, 8 Gy to the lungs), or by fractionated dose (n = 175, 12 Gy were given in 6 fractions over 3 consecutive days to midplane at L4 level, 9 Gy to the lungs). The dose distribution is similar than the ones obtained by a linear accelerator with patients lying on their sides. Patients were treated in a comfortable and highly reproductible position. Organ shielding was easily achievable. This could be a less expensive and reasonable alternative to linear accelerator.International Journal of Radiation OncologyBiologyPhysics 12/1995; 33(4):951-7. · 4.11 Impact Factor -
Article: A fatal thrombotic complication during liver transplantation after aprotinin administration.
Transplantation 07/1994; 57(11):1664-6. · 4.00 Impact Factor -
Article: Total-body irradiation and cataract incidence: a randomized comparison of two instantaneous dose rates.
[show abstract] [hide abstract]
ABSTRACT: To assess the influence of instantaneous total-body irradiation dose rate in hematological malignancies, we randomized 157 patients according to different instantaneous dose rates. Between December 10, 1986 and December 31, 1989 157 patients have undergone a total-body irradiation before bone-marrow transplantation according to two different techniques: either in one fraction (1000 cGy given to the midplane at the level of L4, and 800 cGy to the lungs) or in six fractions (1200 cGy over 3 consecutive days to the midplane at the level of L4, and 900 cGy to the lungs). Patients were randomized according to two instantaneous dose rates, called LOW and HIGH, in single-dose (6 vs. 15 cGy/min) and fractionated (3 vs. 6 cGy/min) TBI groups; there were 77 cases for the LOW and 80 for the HIGH groups, with 57 patients receiving single-dose (28 LOW, 29 HIGH) and 100 patients receiving fractionated total-body irradiation (49 LOW, 51 HIGH). As of July 1992, 16 (10%) of 157 patients developed cataracts after 17 to 46 months, with an estimated incidence of 23% at 5 years. Four (5%) of 77 patients in the LOW group, 12 (15%) of 80 patients in the HIGH group developed cataracts, with 5-year estimated incidences of 12% and 34%, respectively (p = 0.03). Ten (18%) of 57 patients in the single-dose group, and 6 (6%) of 100 patients in the fractionated group developed cataracts, with 5-year estimated incidences of 39% and 13%, respectively (p = 0.02). When the subgroups were considered, in the single-dose group, 3 (11%) of 28 LOW patients, and 7 (24%) of 29 HIGH patients developed cataracts, with 5-year estimated incidences of 24% and 53%, respectively; in the fractionated group, 1 (2%) of 49 LOW patients, and 5 (10%) of 51 HIGH patients developed cataracts, with 5-year estimated incidences of 4% and 22%, respectively (single-dose LOW vs. single-dose HIGH vs. fractionated LOW vs. fractionated HIGH, p = 0.006). There was no statistically significant difference in terms of 5-year estimated cataract incidence between the patients receiving steroids and those not (30% vs. 25%, p = 0.22). Multivariate analyses revealed that the instantaneous dose rate was the only independent factor influencing the cataractogenesis (p = 0.04). We conclude that the total-body irradiation regimen (instantaneous dose rate and/or fractionation) may have an influence on the development of cataracts following bone-marrow transplantation.International Journal of Radiation OncologyBiologyPhysics 02/1994; 28(2):343-7. · 4.11 Impact Factor -
Article: Pharmacokinetics and pharmacodynamics of pipecuronium in patients with cirrhosis.
[show abstract] [hide abstract]
ABSTRACT: To determine the effect of liver cirrhosis on the pharmacokinetics and pharmacodynamics of pipecuronium, the authors administered 100 micrograms/kg of pipecuronium intravenously to eight patients with liver cirrhosis and eight patients with normal liver and renal function undergoing elective abdominal surgery. All patients were anesthetized with thiopental (5-7 mg/kg), nitrous oxide (50-70% in oxygen), and fentanyl in repeated doses (2 micrograms/kg). Plasma concentrations of pipecuronium were determined by high-pressure liquid chromatography. A two-compartment open model was used for pharmacokinetic analysis. Thumb-elicited mechanical response to single-twitch ulnar nerve stimulation was also measured. Total plasma clearance did not differ between controls (2.96 +/- 1.05 mL.min-1.kg-1, mean +/- SD) and cirrhotics (2.61 +/- 1.16 mL.min-1.kg-1). Terminal elimination half-life was 111 +/- 46 min in controls and 143 +/- 25 min in cirrhotics. The total apparent volume of distribution at steady state did not differ between controls (350 +/- 81 mL/kg) and cirrhotics (452 +/- 222 mL/kg). The volume of the central compartment was not different between the two groups. The onset of neuromuscular blocking effect was longer in cirrhotics (233 +/- 112 s) (P < 0.05) than in controls (170 +/- 33 s). The clinical duration (injection until single twitch returned to 25%) was similar between the two groups: 167 +/- 41 min in controls and 165 +/- 48 min in cirrhotics. The authors conclude that hepatic insufficiency due to cirrhosis does not alter the pharmacokinetics and pharmacodynamics of pipecuronium (100 micrograms/kg).Anesthesia & Analgesia 01/1994; 77(6):1203-6. · 3.29 Impact Factor -
Article: Total-body irradiation before bone marrow transplantation. Results of two randomized instantaneous dose rates in 157 patients.
[show abstract] [hide abstract]
ABSTRACT: One hundred fifty-seven patients referred to the Department of Radiation Oncology of the Hôpital Tenon, Paris, France, between December 10, 1986 and December 31, 1989 for total-body irradiation (TBI) were treated according to the following two techniques: (1) either in one fraction (1000 cGy administered to the midplane at L4 and 800 cGy to the lungs) or (2) in six fractions (1200 cGy on 3 consecutive days to the midplane at L4 and 900 cGy to the lungs). The patients were randomized according to two instantaneous dose rates, called LOW and HIGH, in single-dose (6 versus 15 cGy/min) and hexafractionated (3 versus 6 cGy/min) TBI groups. There were 77 patients in the LOW group and 80 in the HIGH group, with 57 patients receiving single-dose TBI (28 LOW and 29 HIGH) and 100 patients receiving fractionated-dose TBI (49 LOW and 51 HIGH). In March 1991, the 4-year relapse-free and overall survival rates were 58.4% and 52.1%, respectively. The 4-year relapse-free survival and survival rates were 54.9% and 50.7% in the LOW group; 61.9% and 53.5% in the HIGH group (P = 0.69 and 0.82, respectively); 60.3% and 50.4% in the single-dose group; and 57.9% and 53.3% in the fractionated group (P = 0.65 and 0.78, respectively). There was no difference in the incidence of graft versus host disease, interstitial pneumonitis, or venoocclusive disease either between the LOW and the HIGH groups or between the single-dose and fractionated-dose TBI groups. The 4-year estimated cataract incidence was significantly higher in the single-dose HIGH instantaneous dose rate group than in the LOW instantaneous dose rate TBI group (P = 0.049). Multivariate analyses showed that instantaneous dose rate and fractionation do not influence the relapse-free and overall survival rates or the incidence of interstitial pneumonitis.Cancer 07/1992; 69(11):2853-65. · 4.77 Impact Factor
