[Reduction of radiation exposure by using storage phosphor radiography on pelvis and lumbar spine].

Purpose: To examine the reduction of radiation dose for radiography of the pelvis and lumbar spine (LS) by using storage phosphor radiography (SPR)?

Material And Methods: Each pelvis and LS of 2 phantoms (3 M) and 2 corpses were X-raxed digitally in an anterior-posterior orientation using SPR (ADC compact, Agfa). The tube current time product (mAs) was diminished gradually while keeping the voltage constant. The surface entrance dose was measured by a Dosimax (Wellhöfer) sensor.

[Reduction of radiation dosage by using digital luminescence radiography on a hand phantom].

Purpose: How much can the radiation dose be reduced for hand radiography by using digital luminescence radiography (DLR)?

Methods And Materials: A hand phantom (3M) with a cyst, two fractures and an "amputation" was digitally exposed in an anterior-posterior orientation using DLR (ADC-70, Agfa). The tube current time product (mAs) was reduced gradually while keeping the voltage constant. The surface entrance dose was measured by a Dosimax sensor (Wellhöfer).

[The reduction of the radiation dosage by means of storage phosphor-film radiography compared to a conventional film-screen system with a grid cassette on a skull phantom].

Purpose: How much can the radiation dose be reduced for skull radiography by using digital luminescence radiography (DLR) compared to a conventional screen film system with a grid cassette?

Methods And Materials: A skull phantom (3M) was x-rayed in anterior-posterior orientation using both a conventional screen film system with grid cassette and DLR (ADC-70, Agfa). The tube current time product (mAs) was diminished gradually while keeping the voltage constant. The surface entrance dose was measured by a sensor of Dosimax (Wellhöfer).

[Sound spectrographic studies in the diagnosis of dysfunctions of mechanical heart valve prostheses (Björk-Shiley prostheses)].

A newly developed real-time sound spectroanalyzer was found to be capable of diagnosing malfunction of prosthetic heart valves (Björk-Shiley prostheses). Sound spectroanalysis was carried out 430 times on 257 patients with a prosthetic heart valve. The valvular click of prosthetic heart valves shows a typical sound spectroanalysis pattern in real time, with a high-frequency peak which diminishes beyond 25 kHz.