Superior Laser Peripheral Iridotomy Confers Greater Risk of Negative Dysphotopsias than Temporal Laser Peripheral Iridotomy.

Purpose: Laser peripheral iridotomy (LPI) is largely used as the first course of action to treat primary angle-closure (PAC). Previous literature has long been divided on the relationship between iridotomy position and dysphotopsia onset. The current study investigates whether there is a correlation between iridotomy position, temporal versus superior, and new onset post-operative dysphotopsia rates.

Methods: The project involves a retrospective chart review of 2,385 lasered eyes. Demographic data and iridotomy-specific data including laterality, iridotomy position, and new onset post- operative dysphotopsias were recorded.

Results: Of 2385 eyes with LPIs, 217 (9.10%) experienced postoperative dysphotopsia. Superior and temporal LPIs were associated with total dysphotopsia rates of 11.20% and 8.01%, respectively. The percentage distribution of dysphotopsias among negative, positive, and non-specific categories were 2.81%, 4.99%, and 1.26%, respectively. Superior LPIs are associated with a greater risk of new onset dysphotopsia than temporal LPI (p = 0.0107), specifically negative dysphotopsia (p < 0.0001).

Conclusions: Patients with superior LPI were more likely to experience negative dysphotopsia onset than those with temporal LPI. Among negative dysphotopsias, positive dysphotopsias, and non-specific symptoms, only negative dysphotopsias were significantly impacted by iridotomy position. Results may influence providers to perform LPI temporally to prevent negative dysphotopsia. Further research into the etiology of dysphotopsia may elucidate further clinical decisions to protect patients from dysphotopsia onset.