Glaucoma & Retinal Diseases

Biography

Biography: Amaghere O. Charles

Abstract

Spontaneous venous pulsation is viewed as a subtle variation in the calibre of the retinal vein(s) as they cross the optic disc. The pressure gradient of the retinal vein varies because of the difference between the intraocular space and the cerebrospinal fluid. Various theories have been propounded to explain what is going on: chief amongst them is that the intraocular pressure rises and exceeds the venous pressure during systole thereby causing the veins to collapse. Retinal venous pressure exceeds IOP, making the vein to expand. Of much importance is the fact that when the intracranial pressure rises, the intracranial pulse pressure rises to equal the intraocular pulse pressure and the spontaneous venous pulsations cease. In this manner, the cessation of the spontaneous venous pulsation becomes a sensitive marker of raised intracranial pressure. The fact that pulsations are increased in patients with significant elevated intraocular pressure, intraocular hypotension and increased intracranial pressure has been associated with absent pulsations. Therapies that lower intraocular pressure without also lowering intracranial pressure (such as topical rather than oral carbonic anhydrase inhibitors) should be favoured.