Abstract and Introduction
Purpose of review: Cataract surgery is the most common surgical procedure performed worldwide. Small pupils have been an eternal challenge for cataract surgeons; insufficient pupil dilation is associated with increased complication rates, including capsule rupture, vitreous loss, iris trauma or postoperative inflammation. The aim of the current review is to present the methods for pupil dilation and the risk factors for a small pupil in a cataract patient.
Recent findings: Risk factors for intraoperative small pupil include diabetes, intraoperative floppy iris syndrome, pseudoexfoliation syndrome, receiving glaucoma medications, having undergone previous ocular surgery and iris sphincter sclerosis from aging. There is a wide range of options to manage the small pupil, including pharmacological treatment, mechanical stretching, dilation with iris hooks or pupil expanders. We recommend a stepwise approach for intraoperative pupil dilation, from pharmacological mydriasis to pupil expanders.
Summary: The current article discusses risk factors for a small pupil and the methods for pupil dilation in a cataract patient. Every cataract surgeon needs to be ready to cope with a small pupil, both manifesting preoperatively and intraoperatively.
Cataract surgery is the most common surgical procedure performed worldwide. With almost 20 millions surgery performed each year it could be considered as the most successful intervention in contemporary medicine. As the procedure has acquired technical advances, with sophisticated preoperative diagnostics and even more precise instruments, the patients' expectations have raised as well.
Small pupils have been an eternal challenge for cataract surgeons. A well dilated pupil is vital for cataract surgery including laser-assisted procedures, as it allows good access to the lens. Small pupils can be associated with increased complication rates, including capsule rupture, vitreous loss, iris trauma or postoperative inflammation. Difficulties to dilate the pupil are not an unusual finding; in a recent study on 1144 eyes undergoing cataract surgery, 6.8% of cases [95% confidence interval (CI): 5.2–8.8%] manifested a pupil size under 6 mm despite the application of the routine dilation regimen. Given that up to 4.0 million cataract surgeries are performed in the United States annually, and up to 20.0 million worldwide, would result in an annual rate of more than a million small pupil operations annually. According to Narendran et al the odds ratio of developing posterior capsule rupture (PCR), vitreous loss or both in eyes with small pupil is 1.45 (95% CI 1.1–1.91). Another study found that in cataract surgery complicated with vitreous loss 54.2% eyes had a pupil diameter of 6 mm or less, and only 38.6% of cases without vitreous loss manifested a small pupil (P = 0.003).
The aim of the study is to present the current methods for managing small pupils during cataract surgery.
Curr Opin Ophthalmol. 2020;31(1):33-42. © 2020 Lippincott Williams & Wilkins