Dose monitoring of health care workers occupationally exposed to ionizing radiation in Mansoura university hospitals

This study aims at evaluating the efficacy of radiation safety in Mansoura University Hospitals [MUHs] and to establish practical dose constraint [DC] for medical application. The study has been conducted upon health care workers [HCWs] occupationally exposed to ionizing radiation in various diagnostic and therapeutic activities in six health premises of MUHs. Four medical applications [radiotherapy, nuclear medicine, general radiology and interventional radiology] and five specialties [medical doctors, physicists, technicians, nurses and non-classified personals] were accounted. Doses were measured on a quarterly basis using thermoluniscent dosimeters [TLD-badges], while pocket dosimeters were used whenever TLD was not available. The annual doses were collected to build up a data base for years 1994-2005. The results show that TLD-badges were used in best situation in Oncology and Nuclear Medicine Dept. to cover less than one third of the exposed HCWs. The occupational doses showed a highly significant difference [p<0.0001] depending on the field of medical application. It is found that HCWs in radiotherapy were exposed to an average annual dose of 1.36 +/- 0.61mSv/y. For interventional radiology, the mean annual dose was found 2.25 +/- 2.47mSv/y unlike that of general radiology 1.07 +/- 0.65mSv/y. The largest sources of occupational exposure came from fluoroscopic radiology .equipments [1.76 +/- 0.92mS/y] followed by Cobalt-60 teletherapy machine [1.12 +/- 0.72mS/y]. The study showed that about 90% of HCWs received doses less than 2mSv/y and only 1.39% reported doses 5mSv or above. Dose constraint level can be set at 2mSv/y in premises of MUHs that may be considered achievable ceiling value referring to acceptably applied practices rather than optimized ones

Estudo da resposta de fotodiodos para dosimetria beta / Study of response of photodiode to beta dosimetry

Neste trabalho foram analisadas as respostas dos fotodiodos comerciais SFH-206, BPY-12 e BPW-34 para uso em dosimetria beta. O resultado obtidos mostram que as respostas destes fotodiodos variam linearmente com a dose, apresentando um desvio menor que 1 por cento. O fotodiodo BPY-12 demonstrou ser mais sensível à radiação do que os outros dois fotodiodos estudados.

Investigación sobre niveles de dosis en exámenes con fluoroscopia gastrointestinal como parte de un programa de control de calidad / An investigation of the levels of radiation exposure in diagnostic examinations involving gastrointestinal tract fluoroscopy

El Servicio de Radiodiagnóstico del Hospital Universitario de la Universidad Federal de Río de Janeiro, juntamente con el Instituto de Radioprotección y Densitometría de la Comisión Nacional de Energía Nuclear, se encuentra desarrolllando programas en el área de garantía de calidad en radiodiagnóstico. Estas actividades contemplan como objetivo importante la optimización de las dosis. Uno de los programas en marcha comprende exámenes de fluoroscopia gastrointestinal. A fin de investigar los niveles de exposición a la radiación fueron realizadas medidas de dosis de entrada en la piel recibidas por pacientes y médicos en exámenes de esofagografía, seriografía y colon, utilizando dosímetros colocados en varias posiciones del cuerpo. En este trabajo se describe la metodología seguida y se muestran los resultados obtenidos hasta el presente. Se hace un análisis del espectro de dosis observadas en pacientes y profesionales, de acuerdo con diversos parámetros tales como ubicación de dosímetros, tiempo de exposición, técnicas empleadas, número de radiografías, etc. También se describen los pasos a seguir con el objeto de concretar la implantación de un programa de control de calidad en los exámenes mencionados

Está correta a dosimetria laser em J/cm2 / Dosimetry in J/cm2: is it correct?

Constataçöes clínicas däo ensejo à revisäo de dosimetria em laser. O artigo mostra que o equacionamento físico está conforme com resultados práticos, indicando cuidados até agora näo levados em consideraçäo na escolha de equipamentos, bem como as densidades de potência e energia influem grandemente nos resultados que se pretende desses aparelhos, bem como na profundidade de penetraçäo do feixe laser