Abstract
Purpose :
Prior studies have indicated that pupillometry detects altered pupillary dynamics in patients who are on tamsulosin. The purpose of our prospective cohort study was to compare pre-surgical pupillary dynamics in patients who have taken tamsulosin with control patients scheduled for cataract surgery. We aimed to identify differences in pupillary dynamics of those tamsulosin patients who developed IFIS during surgery with those who did not. This study will indicate if there is increased risk of IFIS in tamsulosin patients detectable via the Neuroptics NPi-200, a handheld, digital pupillometer.
Methods :
This study included 11 eyes of 11 tamsulosin patients and 31 eyes of 31 control patients. Pupillary dynamics were measured before and after dilation for patients who underwent cataract surgery between July 2015 and August 2015. Resting pupil diameter (mm), constricted pupil diameter (mm), constriction latency (ms), constriction and dilation velocity (m/s) were measured. The surgeon, masked to the groups, determined the presence of IFIS and rated severity based on a literature based grading scale. Patients over the age of 18 were included regardless of existing comorbidities. Two-tailed t-tests were used to compare differences between the two groups.
Results :
Mean pre-dilated max diameter for tamsulosin patients was 3.15±0.66, 16 percent smaller than mean for control patients (3.73±0.93, p=0.03). Mean pre-dilated resting diameter for tamsulosin patients was 2.27±0.37, 16 percent smaller than the mean for controls patients (2.70±0.72, p=0.01). Other pupillary dynamics were not significantly different between the two groups. Of the 11 tamsulosin patients, 45% (5) exhibited IFIS, ranging from grade 1 to grade 3. No significant differences of pupillary dynamics were found between IFIS and non-IFIS Flomax patients. Mean post-dilated max diameter approached significance, with IFIS patients being 17% smaller (5.91±1.16) than non-IFIS (7.15±0.93, p=0.07).
Conclusions :
Pupillometry measured significant differences in pupillary dynamics between patients on tamsulosin and controls. It also identified differences approaching significance between IFIS patients and non-IFIS patients, specifically post-dilated maximum pupil size. Pupillary dynamics of patients on tamsulosin may be measured prior to surgery to determine if IFIS is likely to occur, allowing special precautions.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.