Not Everything Is Spherical Aberration

To describe a clinical case of a patient who had cataract surgery in both eyes and was complaining of haloes at night due to spherical aberration althought his vision was 20/20 uncorrected. He had two monofocal spheric sensar 1 piece IOLs, a 8mm pupil, and a corneal spherical aberration of +0.37. In this case we will review the importance of spherical aberration in IOL selection, but also that patients who suffer from this symptoms, usually tend to have any type of dysphotopsias or night vision symptoms.

The patient underwent an IOL exchange in his right eye for a tecnis za9003 IOL, with an asphericity of -0.27 in order to reduce spherical aberration as minimal as possible four months after the initial surgery. He didnt have any more haloes at night but now complains about positive dysphotopsia. After that the other eye was exchanged

A 55 yo patient underwent uneventvul cataract surgery in both eyes. He had two sensar monofocal spheric IOL placed, and altought vision was 20/20 uncorrected, he complained about seeing haloes at night. The pre op exam was pretty much normal, but he has an 8mm pupil and a spherical aberration of his cornea +0.37.

Four months after initial surgery, he had an IOL exchange in his right eye. The IOL selected was tecnis za9003, with an asphericity of -0.27, in order to reduce spherical aberration from his cornea as much as it can. The surgery went well, but the patient was now complaining about positive dysphotopsia. I decided to exchange the IOL in his left eye for a Bausch & Lomb LI61AO, a silicone IOL with zero spherical aberration. Due to the silicone having a lower refractive index than acrylic, the problem was solved.

He still stays with the positive dysphotopsia because he is happy with his small myopic result as he can see the computer without glasses.

Nowadays he uses brimonidine drops whenever dysphotopsia bothers but he is happy with the result.

Despite having a higher spherical aberration in the eye with a zero asphericity IOL, the night vision symptoms are not bothering him after trying three different types of IOLs.

Spherical aberration needs to be taken into account when choosing IOLs. In some developing countrys spherical IOLs are common due to economical reasons. Patient should be troughly studied before choosing this type of IOL.

If a patient have type A personality as this one had, a big pupil size, and also a considerably high amount of spherical aberration in his cornea, could possibly be a candidate for any type of night vision symptom, regardless the IOL.

Silicone IOL like LI61AO from Bausch and Lomb, specially doing reverse optic capture, should be the IOL of choice when we encounter with some of this problems. Due to its material, the incidence of dysphotopsia is as low as possible even in patients like this one.