El fin de la protección gonadal en radiografía de pelvis: una revisión / The end of gonadal protection in pelvic radiography: a review

Resumen: La protección gonadal ha sido durante largo tiempo un importante factor para abordar el requisito "tan bajo como sea razonablemente posible" ALARA. El presente artículo realiza una revisión sistemática sobre la utilidad de la protección gonadal en la radiografía de pelvis en la cual se han destacado los factores que tienen que ver con su realización diaria, es decir, la dosis de radiación involucrada, la radiosensibilidad de las gónadas, la posición del protector gonadal y el factor psicológico de la población en relación con su uso. La incorporación de equipamientos modernos, con dosis y protocolo optimizados, transforma el beneficio de la protección en un tema al menos debatible. Mientras algunos siguen respaldando la medida, otros organismos y autores ya no la respaldan. Es necesario reconsiderar prácticas actuales fundadas en consensos científicos que pueden estar obsoletos y considerar el factor de cambio cultural basados en estos nuevos consensos para su implementación, sin generar mayor preocupación en la población.

Abstract: Gonadal protection has long been an important factor in addressing the ALARA "as low as reasonably possible" requirement. This article performs a systematic review on the usefulness of gonadal protection in pelvic radiography, in which the factors that have to do with its daily performance have been highlighted, that is, radiation dose involved, the radiosensitivity of the gonads, the position of the gonadal shielding and the psychological factor of the population in relation to its use. The incorporation of modern equipment, with optimized dose and protocols, transforms the benefit of gonad shielding into an issue that is at least debatable. While some continue to support the measure, other agencies and authors no longer support it. It is necessary to reconsider current practices based on scientific consensus that may be obsolete and consider the factor of cultural change based on these new consensus for its implementation, without generating major concern in the population.

Niveles de dosis en radiología convencional / Radiation doses in conventional radiology

Se ha medido la dosis en la superficie de entrada de ojos, tiroides y gónadas en pacientes sometidos a estudio de radiografía de tele de tórax mediante dosimetría termoluminiscente. Se usaron 5 dosímetros en cada una de las exploraciones; encontrándose los siguientes rangos de dosis: 20 mGy a 350 mGy. En el caso de los pacientes pediátricos se propone incluir la información de las dosis recibidas en su cartilla de vacunación con el fin de hacer un seguimiento de los posibles efectos nocivos en su salud.

Doses have been measured at the entrance surface of eyes, thyroid and gonads in patients undergoing chest x-ray studies, using thermo-luminiscent dosimetry. Five dosimeters were used in each investigation, and doses ranged from 20 mGy to 350 mGy. In the case of pediatric patients, it is proposed that dose information from diagnostic examinations is included in the vaccination chart in order to correlate with findings at follow-up.

Gonad, bone marrow and effective dose to the population of more than 90 towns and cities of Iran, arising from environmental gamma radiation

Since 1996 the assessment of environmental gamma radiation dose in residential areas of Iranian towns and cities has been accomplished for 10 counties. As a practical method and based on the results of a pilot study, in order to attribute the final results to the whole residential area of a town five stations were selected for every town. The location of individual station was studied closely to comply with recommended conditions in the literature. RDS-110 was employed to measure gamma dose rate for one hour. Average annual dose rates plus conversion coefficients were employed to estimate gonad, bone marrow, equivalent and effective dose. Minimum and maximum annual bone marrow and gonad dose equivalent attributed to environmental gamma are 0.24 mSvy[-1] [for both tissues] and 1.44 and 1.46 mSvy[-1], respectively. Average gonad and bone marrow doses for North Khorasan, Boshehr and Hormozgan provinces were less than the corresponding values for normal area

Endolymphatic irradiation in preparation for renal transplantation: a 26-year follow-up

The aim of the present study was to analyze the long-term evolution of patients submitted to endolymphatic irradiation as a pre-transplant preparation. Setting: Referral center of university hospital. Design: Case-control study. Main outcomes measures: The study was designed to evaluate the incidence of rejection, kidney loss, leukopenia, infection, and graft survival in the group treated (group 1) prior to surgery, compared to a control group (group 2) composed of patients under identical clinical conditions (Sex, age, type of donor, immunosuppresive therapy and time of transplant) that did not undergo treatment preparation. Patients: Patients were selected from amongst transplatation candidates on a long-term waiting list, some with a high level of antibodies against panel. The control group was chosen from amongst recently transplanted patients. Patients in the treated group received lipoidine containing I with specific activity ranging between 4 and 6 mCu/ml. Results: A significant difference between the two groups was found with regard to the incidence of rejection crises (21.0 per cent in group 1 and 73.6 per cent in group 2; P=0.003), and the maintenance dose of azathioprine (smaller in group 1; P<0.01). As to kidney graft loss due to rejection, a tendency to significance could be identified (10.5 per cent in group 1 and 42.1 per cent in group 2; P=0.063); however, the difference was not significant the two groups in terms of reversibility of rejection episodes during the first 60 post-transplant days. Conclusions: The authors concluded that this method, besides being relatively innocuous (there was no compromising of either the thyroid gland or of gonad function and there was no increase in tumor incidence), has na extended immunosuppressive effect, and can be indicated for cadaveric renal allograft recipients, especially those showing high panel reactivity.

Estudo comparativo entre riscos carcinogênicos decorrentes de radiografias realizadas com os aparelhos panorâmicos Status X e Panoramax em órgäos críticos: globo ocular, tireóide e gônadas / The comparative study between carcinogenic risk deriving of the radiography using panoramic equipment Status X and Panoramax in critical organs: eye ball, thyroid gland and gonads

Neste trabalho o autor pesquisa e compara as doses absorvidas em três órgäos considerados críticos: globo ocular, glândula tireóide e gônadas, advindas de tomadas de radiografias com dois aparelhos panorâmicos, um com foco emissor intrabucal - o STATUS X e outro com foco emissor extrabucal - o PANORAMAX. As doses de radiaçäo absorvidas foram mensuradas através de dosímetros termoluminescentes de fluoreto de lítio (DTL Lif 700) colocados nos três locais de estudo. Com os resultados obtidos foi estabelecida uma relaçäo com os dados fornecidos pela UNSCEAR (1977) no que diz respeito aos riscos biológicos. A probabilidade de incidência de tumor maligno foi calculada pelo relatório da ICRP (1977). Dos resultados obtidos, concluímos que o aparelho panorâmico com foco emissor intrabucal, o STATUS X, produz maior índice de dose de radiaçäo absorvida que o PANORAMAX com foco emissor extrabucal, porém ambos promovem dose de absorçäo à radiaçäo cuja probabilidade de instalaçäo de um tumor maligno é menor que 1 (um) para um milhäo de exames

Dose gonadal em radiografias de tórax em berçário / Gonadal doses in hest radiographs in baby nursery

Como a radiografia de tórax é utilizada em determinadas afecçöes pulmonares de recém-nascidos mais de uma vez ao dia, para avaliaçäo da rápida mudança das condiçöes clínicas, constitui uma das mais importantes causas de exposiçäo `as radiaçöes ionizantes na infância. Por proteçäo radiológica entendem-se medidas e condutas destinadas a proteger o indivíduo, seus descendentes e a comunidade como um todo, ao mesmo tempo estabelecendo normas para as atividades nas quais a exposiçäo `a radiaçäo se origina. Este trabalho visa medir a dose de radiaçäo que atinge as gônadas, com a utilizaçäo de dois tipos diferentes de aparelhos portáteis usados para a obtençäo de radiografias de torax em berçarios. O material utilizado foi o seguinte: a) aparelhos portáteis com colimador de raios X com dispositivo luminoso, e sem colimador, o qual irradia a criança como um todo; b)simulador de tecido equivalente representando o tonco de um recém-nascido; c)dosímetros termoluminescentes de fluoreto de lítio em forma de gräo, para as medidas de dose de radiaçäo. Foram realizadas inúmeras exposiçöes, com as técnicas de rotina, com colocaçäo de dosímetros no tórax e na regiäo gonadal, com e sem colimaçäo, para que se obtivessem valores de soses significantes. Como em nosso meio a fabricaçäo dos equipamentos portáteis é voltada principalmente ao do tipo sem colimaçäo, espera-se que haja uma radiaçäo excessiva nas gônadas quando houver comparaçäo com as doses obtidas com os aparelhos portáteis com colimaçäo, o que näo justificaria a utilizaçäo desses modelos na rotina diária dos berçários, devida aos riscos da radiaçäo