Evaluation of work practices and radiation dose during adult micturating cystourethrography examinations performed using a digital imaging system.

A micturating cystourethrography (MCU) examination is a specific radiological procedure that is performed under fluoroscopic screening to visualize the bladder by filling it with contrast material and to evaluate the urethral morphology during voiding. It is necessary to evaluate radiation dose during MCU examination since it involves radiosensitive organs such as the gonads. Radiation dose imparted to 109 patients undergoing MCU examination were measured using a dose-area product (DAP) meter. Patients were categorized into two groups based on whether filling of the bladder with contrast medium was done retrogradely (MCU) or by the suprapubic percutaneous route (SP-MCU). The DAP values to Group A (MCU) and Group B (SP-MCU) patients varied from 0.43 Gycm(2) to 9.26 Gycm(2) and 0.54 Gycm(2) to 9.87 Gycm(2), respectively. Reduction of radiation dose to patients was possible by the use of optimized exposure factors, precise collimation of X-ray beam, use of 0.2 mm copper filters and by acquiring images digitally.

Radiation dosimetry using junction field-effect transistor detectors.

The use of junction field effect transistors (JFET) has been studied by connecting them in a bridge circuit. With a suitable back-up circuit, it was possible to measure doses as well as dose-rates. It was possible to alter the sensitivity of the JFET bridge by varying the biasing components of the JFET. Easy temperature compensation was also possible. However, response of the JFET to radiation showed energy dependency similar to that of semiconductor diodes.

Weight appreciation in the hand in normal subjects and in patients with leprous neuropathy.

The Weber fraction was used as an index of the sensitivity with which subjects appreciated weights ranging from 20 to 500 g suspended from the middle finger. Normal subjects were able to appreciate weight when it caused cutaneous compression alone. The sensitivity increased when subjects lifted weights by flexing the metacarpophalangeal joint. This increase was more marked for weights ranging from 20 to 100 g than for weights ranging from 200 to 500 g. When subjects lifted weights by flexing the elbow joint, the sensitivity with which they appreciated weight was comparable to that from cutaneous compression alone. Leprous subjects having glove anaesthesia were unable to appreciate any weight up to 500 g when it caused cutaneous compression alone. However, they were able to appreciate weights above 200 g when they lifted weights by flexing the metacarpophalangeal or elbow joints.