Effects of Deep Sclerectomy on Retrobulbar Hemodynamics

Abstract

Purpose: : Deep sclerectomy is an efficient intraocular pressure lowering operation. Aim of the present study was to investigate the effect of deep sclerectomy on retrobulbar blood flow velocities.

Methods: : Intraocular pressure (IOP) as well as peak systolic velocity (PSV) and end-diastolic velocity (EDV) in the short and long posterior ciliary artery (SPCA, LPCA), central retinal artery (CRA) and ophthalmic artery (OA) were recorded by color Doppler imaging (CDI) in 24 glaucoma patients before and four weeks after deep sclerectomy.

Results: : Four weeks after deep sclerectomy IOP was significantly lowered from 16.0 (±0.8) mmHg to 13.3 (±0.7) mmHg (P=0.01). CDI measurements before and after deep sclerectomy revealed no significant change of the PSV (8.7±0.6cms^-1 vs 9.0±0.4cms^-1; P=0.67) and of the EDV (2.4±0.2cms^-1 vs 2.7±0.2cms^-1; P=0.30) in the SPCA or in any of the other investigated vessels.

Conclusions: : Despite a significant drop in IOP no change in retrobulbar blood flow velocities was detected after deep sclerectomy. This finding can be interpreted as another hint, that even in glaucoma patients ocular blood flow is kept constant over a certain range of IOP due to local regulatory mechanisms.

Keywords: blood supply • intraocular pressure • imaging/image analysis: clinical