Effect of primary selective laser trabeculoplasty on tonographic outflow facility - a randomised clinical trial.

Saurabh Goyal (1) , Laura Beltran-Agullo (1) , Safina Rashid (1) , Shaheen Shah (2) , Remin Nath (1) , Adanna Obi (1) , Kin Sheng Lim (1)

1 Guy's and St Thomas' Hospital [London]
2 LSHTM - London School of Hygiene and Tropical Medicine

Purpose: To investigate the effect of 180º versus 360º primary Selective Laser Trabeculoplasty (SLT) on tonographic outflow facility (TOF) and intraocular pressure (IOP). Design: Prospective, single masked randomised clinical trial. Participants: Patients with untreated primary open angle glaucoma or ocular hypertension both with IOP >21-35mmHg. Methods: Forty patients randomly treated with ? d 180º or 360 º SLT after baseline TOF (electronic Schiøtz tonography) and IOP measurement which were repeated after one month. One eye from each patient was randomly selected for analysis. Eight untreated eyes were included as a control group. Main Outcome Measures: TOF and IOP difference. Responders were defined as having at least a 20% reduction in IOP. Results: Three patients were excluded due to poor tonography. There were eighteen eyes in 180º group and nineteen eyes in the 360º group. TOF increased significantly (180º p=0.003, 360º p=0.005) and IOP decreased significantly (180º & 360º p<0.001) from baseline. There were no significant differences between the two groups as regards the increase in TOF (180º group 37.5%, 360º group 41%, p=0.23) and decrease in IOP (180º group 24%, 360º group 35%, p=0.35). There were similar number of responders in 180º group (72%) as compared to 360º group (89.5%, p=0.23). TOF and IOP did not change significantly from baseline in the control group (TOF-8% increase p=0.48, IOP-4% decrease p=0.33). Conclusions: Primary SLT significantly increased the tonographic outflow facility and decreased the IOP in patients with primary open angle glaucoma and ocular hypertension but no statistically significant differences were found between the 360º and 180º groups. The level of IOP reduction due to primary SLT treatment could not be explained by the increase in TOF alone.

Mots clés: Aqueous humour; Intraocular pressure; Physiology; Treatment Lasers; Clinical Trial

Saurabh Goyal, Laura Beltran-Agullo, Safina Rashid, Shaheen Shah, Remin Nath, et al.. Effect of primary selective laser trabeculoplasty on tonographic outflow facility - a randomised clinical trial.. British Journal of Ophthalmology, 2010, 94 (11), pp.1443. ⟨10.1136/bjo.2009.176024⟩. ⟨hal-00557357⟩