The effects of surgical factors on postoperative astigmatism in patients enrolled in the Infant Aphakia Treatment Study (IATS)

Abstract

Purpose To evaluate the impact of surgical factors such as incision type, number of sutures, and technique of closure on postoperative astigmatism in infants undergoing cataract extraction with or without intraocular lens implantation. Methods The IATS is a multicenter (n=12) clinical trial in which 114 infants with unilateral congenital cataracts were randomized to undergo cataract extraction with intraocular lens (IOL) placement or contact lens aphakic correction. Surgical videos were reviewed with regard to incision type and location, whether the incision was extended, the number of sutures placed, and technique of closure. Corneal astigmatism was measured using a handheld keratometer prior to surgery and at 1 year of age. Results Corneal astigmatism decreased from a mean of 1.92 D at baseline to 1.62 D at age 1 year in the CL group, but remained almost unchanged from 2.00 D to 2.09 D in the IOL group (p=0.023). There was no statistical difference between the amount of corneal astigmatism irrespective of incision type (p=0.214) and no increase in astigmatism with extension of the incision to facilitate IOL placement (p=0.849) at 1 year. The number of sutures and technique of closure did not influence the amount of astigmatism at 1 year. Conclusions At the age of one year following cataract extraction in infants, contact lens correction and the lack of IOL placement are associated with a significant decrease in postoperative corneal astigmatism compared to intraocular lens placement. No other surgical factors considered in this study had a statistically significant impact on corneal astigmatism.

Axial Length Shortening After Cataract Surgery: New Approach to Solve the Question

“…For this reason several authors concentrated their attention on how to minimize astigmatism onset after surgery, focusing their attention to the astigmatism present before 22–24 and after surgery. 25–29 To make such an evaluation, it is mandatory to perform a vectorial analysis. 30 However, we decided not to check this in our patients because this topic has been widely studied in the international literature, 25–29,31 and we could have added no new information.…”

Biometry and corneal aberrations after cataract surgery in childhood

“…However these studies are of older date when large corneal incisions were used. A more recent study in children undergoing unilateral surgery at age 28 days to <7 months and evaluated at 1 year of age found that corneal astigmatism regressed in aphakic children but remain unchanged in pseudophakic children 20 . Interestingly, a long‐term study of 12 pseudophakic eyes from nine children showed an increase in corneal astigmatism over time 11 .…”

“…A more recent study in children undergoing unilateral surgery at age 28 days to <7 months and evaluated at 1 year of age found that corneal astigmatism regressed in aphakic children but remain unchanged in pseudophakic children. 20 Interestingly, a long-term study of 12 pseudophakic eyes from nine children showed an increase in corneal astigmatism over time. 11 Stepwise regression analysis did show a higher level of astigmatism on the back of the cornea associated to pseudophakia but no association between pseudophakia and the level of astigmatism on the front of the cornea was found.…”

Management of Contact Lenses and Visual Development in Pediatric Aphakia

“… 18 , 19 , 20 , 22 , 23 , 28 , 29 The results of the studies indicated that CL wear is more advantageous in infancy, IOL implantation is safer after 2 years of age, and secondary IOL surgery at later ages will result in less refractive error. 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 …”