Effectiveness Of Selective Laser Trabeculoplasty (Slt) Correlated With Grade Of Pigmentation Of The Trabecular Meshwork Over A 12 Month Period

To report and assess the effect of selective laser trabeculoplasty (SLT) treatment correlated with different degrees of pigmentation of the trabecular meshwork in glaucoma and ocular hypertension over a 12 month period following a 360° application scheme in 2 sessions.

Retrospective, noncomparative observational case series

80 eyes of 52 patients with ocular hypertension or glaucoma were followed up for 12 months after initial SLT treatment. Two SLT treatments with 94±11 pulses each were applied in 180° per eye by the same ophthalmologist. Energy levels ranged from 0.8-1,0mJ per pulse with no regard to the existing topical treatment. Grade of pigmentation was rated using a arbitrary scale ranging from 0 to 3, where 0 represents no and 3 heavy pigmentation. If grade of pigmentation  changed from the top to the bottom location, an average was estimated. IOP was measured 4 weeks, 3, 6 and 12 months,  after final SLT treatment, All treatmens were performed with ARC Cito 532 SLT laser. 

Baseline IOP was 23.2 (±5.3) mmHg and differed not significantly between groups. Correlation with grade of pigmentation showed after 4 weeks sigificantly higher IOP reductions in grade 2 and 3 eyes (5.4mmHg and 4.6mmHg) than in grade 0 and 1 eyes ( 2.2mmHg and 3.4 mmHg). These results could still be seen after 12 months, although with a slight increase in IOP. Intraocular inflammation or other side effects where not to be seen in any of the treated eyes.

These results show a higher SLT effect in eyes with a higher grade of trabecular meshwork pigmentation. The effect lasted during the 12 months follow-up period.