Selective laser trabeculoplasty in exfoliative glaucoma eyes with prior argon laser trabeculoplasty

Abstract

Purpose: To explore the efficacy of selective laser trabeculoplasty (SLT) within eyes with exfoliative glaucoma and history of prior argon laser trabeculoplasty (ALT). Methods: A single-centre trial consisting of 47 patients (47 eyes) with uncontrolled exfoliative glaucoma. The main outcome measure was intraocular pressure (IOP) reduction 3 and 9 months after SLT. Treatment success was defined as reduction from the preoperative IOP by 20% and 2 mmHg (<12 mmHg), 3 mmHg (12-16 mmHg) or 4 mmHg (>16 mmHg) depending on the baseline IOP. Results: Patient age was 79.3 AE 7.6 years (mean AE SD) and gender distribution 15 males and 32 females. The mean pre-SLT IOP was 15.6 AE 5.1 (range 9-28) mmHg, and mean number of glaucoma drugs 2.0 AE 1.2. The mean interval between prior ALT and SLT was 44.0 AE 36.9 (range 11-137) months. After SLT, the mean IOP change was À2.7 AE 4.2 mmHg (À14.8 AE 23.5%) at 3 months, and À2.8 AE 3.5 mmHg (À16.3 AE 19.4%) at 9 months. Pre-SLT IOP correlated with the IOP reduction at 3 months (r = 0.530, p < 0.001) and at 9 months (r = 0.432, p = 0.007). The overall success rate was 50% at 3 months, and 42% at 9 months. At both 3 and at 9 months, the cut-off level for treatment success was achieved when preoperative IOP was 18 mmHg and above. IOP lowering effect of SLT did not correlate with the number of glaucoma drugs, age, gender or use of prostaglandin inhibitors. Neither postoperative iritis nor other adverse effects were documented during the follow-up. Conclusions: Selective laser trabeculoplasty is a safe and noteworthy treatment option to reduce IOP in exfoliative glaucoma eyes, especially with pre-SLT IOP over 18 mmHg.

The Effect of Primary Argon Laser Trabeculoplasty on Intraocular Pressure Reduction and Quality of Life in Patients with Pseudoexfoliation Glaucoma

“…Another two patients from this group had transient IOP elevation, which was efficiently treated within the next 3 days. Although the exact mechanism of action of ALT is still unknown, there are two theories trying to explain how ALT acts in reducing IOP ( 7 ). According to the mechanical theory, transmitted thermal energy causes tissue contraction and stretching of the trabecular meshwork.…”

“…The main restriction in primary ALT could be its transient effect. It is known that after approximately five years, laser-made spots fade away, which causes IOP rise and the procedure has to be repeated ( 7 , 8 , 20 ). Some investigators advocate that primary ALP be part of glaucoma treatment in some specific conditions ( 20 , 21 ), including patients suffering from dementia, rheumatic and mental disorders, or noncompliant patients.…”

“…Electromagnetic energy generated by argon laser gets converted into thermal energy. This causes thermal burn of the trabecular meshwork, which consecutively improves aqueous humor resorption ( 6 , 7 ). In some cases, argon laser trabeculotomy can be used primarily.…”

Selective laser trabeculoplasty as adjunctive treatment in pseudoexfoliative glaucoma patients

“…Immediately before treatment, IOP was measured and after that 0.5% solution of apraclonidine was instilled in the treated eye with the aim to prevent IOP spikes [7,8].…”

“…Sometimes higher energy was required for the treatment of the superior, less pigmented angle. Approximately 100 adjacent, but non overlapping, laser spots were placed over 360° of the TM [8].…”