introduction: nasopharyngeal carcinoma is one of the most common malignancies in the head and neck region and radiotherapy is its treatment of choice. in spite of the fact that it is widely used, due to the presence of many sensitive organs or tissues in this region, patients may suffer from a wide range of side effects. one such sensitive tissue is the spinal cord. if the absorbed dose to spin...

Introduction: Digital radiography possesses a wide dynamic range and has a major advantage in producing an acceptable image of diagnostic value even though overexposure occurs. Lumbar spine (LS) radiography is the most common examinations that gives high radiation dose to patients and accounts for the highest collective population dose of any conventional radiographic ...

The operation of the bowtie filter in x-ray CT is correct if the object being scanned is properly centered in the scanner's field-of-view. Otherwise, the dose delivered to the patient and image noise will deviate from optimal setting. We investigate the effect of miscentering on image noise and surface dose on three commercial CT scanners. Six cylindrical phantoms with different size and materi...

This survey analyses data from 17 French burn units with respect to age, severity of injury and survival of patients admitted to hospital during 1985. Of the 2398 patients treated, more than half were between 15 and 50 years old. About 90 per cent of the patients had burns covering less than 50 per cent of the body surface area. The overall mortality rate was 11.8 per cent. The LD50 for the 239...

Efficacy of low-dose, intra-dermal hepatitis B vaccination was assessed among sixty-one doctors and paramedical staff of Chandka Medical College Hospital, Larkana. Subjects were randomly divided into two groups. Group-A (n = 25) received 20 micrograms of purified Hepatitis B Surface Antigen (Euvax B, LG Chemicals) by i.m. injection in the deltoid by 0, 1 and 6 schedule while group B (n = 36) re...

The objective of this work was to estimate patient doses (dose-area product, organ dose, effective dose and entrance surface dose) for barium procedures. A total of 175 procedures, in 175 patients, for five different examination categories was analysed. Dose-area product was determined using a transmission ionization chamber. Organ dose and effective dose were assessed using a knowledge of the ...

background: to suggest south india ct diagnostic reference levels (drls) by collecting radiation doses for the most commonly performed ct examinations. materials and methods: a pilot study investigated the most frequent ct examinations. 110 ct sites were asked to complete a survey booklet to allow the recording of ct parameters for each of 3 ct examinations during a 1 year time period. dose dat...

Background: Intraoral radiographies are the most frequent X-ray examinations in humans. According to International Commission on Radiation Protection (ICRP) recommendations, the selection of a diagnostic reference level (DRL) should be specific to a country or region. Critica l organs such as thyroid gland are exposed to X-rays in intraoral radiography and these exposures should be kept as low ...