Changes in pressure pulse amplitudes of normotensive diabetic eyes after panretinal photocoagulation. A long term study with comparison of xenon arc and argon laser

Abstract

Among 40 diabetic patients with normal intraocular pressures, a comparison of a long term (half a year) pressure pulse amplitude (IOPA) lowering effect of attempted equivalent monocular panretinal xenon arc and argon laser photocoagulation was made from measurements in 32 patients. For the bilateral simultaneous IOPA recordings the applanating suction cups were used. IOPA recordings with identical IOP levels of treated eye and control eye were aimed at, and this experimental condition was obtained in 23/40 pairs of eyes before treatment and in 21/40 and 19/40 pairs of eyes after 1 and 6 months, respectively. The long term IOPA lowering effect of treatments with the xenon arc as well as the argon laser was approximately 20%, that is averagely 0.25-0.50 mmHg. The present investigations demonstrated a long term reduction of the IOPA of the same magnitude as the previous reported short term (one month). The retrobulbar anaesthesia had no significant influence on the result and there were no changes in the ocular rigidity.