Abstract
Purpose: :
To measure the IOP lowering effect of SLT in patients with open angle glaucoma and insufficient control of IOP under maximum tolerated therapy.
Methods: :
Open-label, non-controlled, prospective, single center study. Preoperative examinations included best corrected visual acuity (VA), Goldmann applanation tonometry (GAT), slit lamp examination, gonioscopy, and non-dilated funduscopy.SLT was performed using a frequency doubled, Q-switched Nd:YAG laser (Ellex Medical Pty Ltd., Adelaide). Preoperatively, one drop of Brimonidine was administered. We treated 360° of the trabecular meshwork (TM) applying 100 non-overlapping laser spots. Energy was chosen depending on the grade of TM pigmentation. No anti-inflammatory drugs were applied postoperatively. A control of IOP was obligatory 2 hours after laser treatment.Postoperative examinations were done on day 1, 30, 90 and 180 including VA, GAT, slit lamp examination, non-dilated funduscopy, and gonioscopy. Preoperative medication was continued unchanged until 90 days and then reduced if possible.
Results: :
30 eyes of 30 patients were included. Mean follow up was 174 days (±57.9, 33-249). Mean IOP decreased from 19.6 mmHg ± 4.69 preoperatively to 15.2 mmHg±3.2 (-22.8%, p < 0.001) at 30 days, 15.8±3.5 mmHg (- 19.2%, p= 0.001) at 90 days, and 17.4±2.8 mmHg (- 11.4%, p= 0.09) at 180 days. There was no significant change in visual acuity over the complete period of follow up. Mean number of IOP lowering substances decreased from 2.4 preoperatively to 1.9 after 180 days (not significant). No serious complications occurred during or after SLT treatment. In 12 cases a mild anterior chamber (AC) inflammation was diagnosed at day 1, which resolved completely without additional therapy. 3 patients developed a paradox rise of IOP 2 hours after SLT and were treated additionally with 250 mg acetazolamid. No synechia formation in the AC angle was observed.
Conclusions: :
SLT is a non-thermal laser treatment without coagulative tissue damage. It can reduce IOP up to 22 % without severe side effects or complications.
Clinical Trial: :
www.clinicaltrials.gov NCT00801658
Keywords: laser • trabecular meshwork • anterior segment