Neurosensory Control of Intraocular Pressure in the Human Eye. A Fundamental and Clinical Correlation

Abstract

The maintenance of intraocular pressure (IOP) and its regulation are under the control of the sympathetic, parasympathetic, and sensory nervous systems. This study investigated the influence of these systems on the nyctohemeral variations of the IOP. Hourly pressure curves were established in normal subjects both before and after blockade of one or several ocular receptors. Timolol, guanethidine, atropine, and indomethacin were used either by themselves or in combination. In addition, hourly pressure curves were established for patients who had undergone either section or high frequency thermocoagulation of the first trigeminal branch. Comparison of the results from either pharmacological blockade or anatomical lesion provides the first evidence that nyctohemeral variations of the IOP are under reflex sensory control. The possible role of endogenous prostaglandins and plasma cortisol are discussed.

Key Words:

• intraocular pressure
• sensory nervous system
• autonomic nervous system
• trigeminal system
• human eye