Study Of Higher Order Aberration And Its Effect On Visual Performance In Patients Undergoing Miol Implantation

Purpose of the study is to understand the incidence of visually significant Higher Order Aberration (HOA) using an aberrometer, in patients undergoing cataract surgery with prebyopia correcting IOL (PCIOL)  implanation and to under their effect in visual performance in various PCIOL implanted in the patient.

Single centre observational retrospective study done at a terteriary eye care centre in a tier 2 city of India 

All patients who underwent cataract surgery were subjected to corneal aberrometry before the surgery. A total of N=300 patients ( 600 eyes) were analysed. All patients who had corneal pathology causing irregular topography and HOA were excluded. Out of these N=50 patients who underwent a trifocal IOL were assigned to group A (PanOptix Alcon) while N=50 patients who underwent an EDOF IOL implant were assigned to group B, for the purpose of the study. RMS of total HOA , 3rd order trefoil Z (3, ±3) and 3rd order coma Z (3, ±1) were considered for 6mm pupil using Scheimflug-Placido based topographer (SIRIUS +), for the study.

Of the 300 patients analysed over 6 months, N=90 patients (30%) had significant HOA (p<0.05). Out of these N=50 had coma HOA while N=40 had trefoil HOA. N=5 had both , however the presence of one HOA over the other was not significant statistically. The incidence of HOA in patients of both groups was similar to control, with group A having N=14 patients and group B having N=16 patients having HOA. While the difference in  BCDVA, BCIVA and BCNVA was not statistically significant across all groups, the patients having HAO in both groups had higher complains of visual dysphotopsia as compared to control. Noteworthy was that patients having trefoil HOA were significantly unhappier with EDOF lens as compared to trifocals or control group. 

HOA are often overlooked aspect in routine cataract surgery workup and can be of significant importance in patient choosing PCIOL. As shown by our study, HOA are often present in as much as 30% of population, which can lead to a significant complains in visual performance and dysphotopsia , often wrongly atributed to PCIOL. Special mention is Trefoil aberration which had higher visual distatisfaction in patients getting EDOF as compared to Trifocals. Overall , patients with clinically significant HOA should be counselled to avoid the PCIOL in view of higher visual complains.