Goniometer in use

Goniometer

The polarized light goniometer is a machine for making on-line recordings of the relative and absolute angular displacements and velocities of adjacent and non-adjacent limb and body segments. It has been developed by a team in the Department of Human Sciences at Loughbor- ough University of Technology, headed by Mr. D.L. Mitchelson. Work started in 1973 followed by 3 years of clinical trials. The manufacturers are Crane Electronics Ltd. It provides a fast, efficient and objective method for quantitatively discriminating between the effects of different kinds of treatments or surgical procedures and the means for monitoring the progress of individual patients and so facilitates more accurate prognosis. A belt pack is placed around the patient’s wrist and transducers attached to her limbs, and connected to the machine which makes a recording of movements during a predetermined exercise. The traces made by suffering patients may be compared with normal results,

and progress after treatment followed.

Crane Electronics Ltd Station Road, Stoke Golding, Nuneaton, Warwicks, UK Tel: (0455) 212157

Critical flicker fusion monitor

Claimed to be the first commerc- ially available instrument specifi- cally designed for the measurement of critical flicker fusion frequency, the model 1199 from System 696 Ltd is supplied complete with an optically designed sight tube. The flicker frequency of the red light presented to the subject is measured to an initial accuracy of 30 ppm. The light source is diffuse, collimated and parallel, eliminating peripheral vision effects.

Novel design has overcome the difficulties inherent in the measurement of the low frequen- cies (17-60Hz) involved, which in the past have obliged users of the technique either to measure the period of the lamp driving signal and then calculate its reciprocal, or to wait ten seconds for a conventional counter timer to measure the frequency. The model 1199 Critical Flicker Fusion Monitor resolves to 0.1 Hz in only half a second, and presents the result on a large three digit display having good visibility in high ambient light. In addition the linear relationship between the rotation of the frequency control and the frequency is linear and this and the use of a ten turn knob eliminates the need for a very steady hand on the control. The instrument allows easy exploit- ation of a technique which is recognised for its sensitivity in demonstrating the changes in visual discrimination occurring after the administration of centrally-acting drugs. The instrument is priced at E195.

A.I. Frampton System 696 Ltd. 73 Tabley Road, London N7 UK.

Blood samples with less distress

Radiometer of Copenhagen has introduced a specially-designed syringe - the B109 Arterial Blood Sampler - for obtaining anaerobic blood gas samples. In use, it fills spontaneously without requiring any plunger manipulation. Only one hand is needed to hold the syringe once the puncture is made, and the other can therefore be used to steady an arm or wrist. It is a timesaver for physicians, since the same artery can be used for repeated arterial punctures.

Patients say they have felt far less distress with this syringe compared to normal PH/blood gas syringes, and arterial damage is minimal.

The 1 ml plastic syringe is supplied with a G23 stainless steel hypodermic needle. Individually packaged unheparinized syringes are radiation sterilized, and available in boxes of 135, 1.350 or 4.050.

Radiometer A/S Emdruprej 72 DK-2400 Copenhagen NV Denmark.

B109 Arterial blood sampler from Radiometer, Copenhagen

76 J. Biomed. Eng. 1979, Vol. 1, January