Abstract
Purpose :
Femtosecond laser assisted cataract surgery is associated with pupillary constriction. This study aimed to look at patient and surgical factors predisposing to abnormal pupil behaviour during FLACS.
Methods :
This prospective observational study included all patients undergoing FLACS in the Princess of Wales Hospital, Bridgend, UK between February and June 2017. Pupils were measured with a ruler at three time points; immediately before and after laser pre-treatment, and at the start of surgery. Pupil behaviour during surgery was noted in descriptive terms, patient demographic, co-morbidities, eye measurements, suction on time, shifting time and laser energy levels were recorded.
Results :
Seventy- three eyes were included. Average patient age was 74.84 +/- 9.1 years. Mean horizontal pupil sizes immediately before and after femto pre-treatment were 7.87 +/- 0.87mm and 7.7 +/- 0.89mm respectively (P<0.0005). Mean horizontal pupil size at the start of surgery was 6.83 +/-1.43 mm (P<0.0005). Short capsulotomy – pupil distance (P=0.01), shallower anterior chamber (P=0.0012), smaller pre-operative pupil size (P= 0.045) and longer suction on time (P= 0.0019) were significantly associated with intra-operative miosis during FLACS. Longer delays between dilating drops and surgery predisposed to progressive pupillary miosis. Use of topical diclofenac within 2 hours of surgery was observed in eyes with sustained mydriasis.
Conclusions :
FLACS can result in significant pupil miosis. Eyes particularly at risk are ones with smaller pre-operative pupils and shallower anterior chambers, subjected to longer suction on time. A regular dilating drop regime and NSAIDs application close to surgery could be protective against this phenomenon.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.