EyeWorld Asia-Pacific June 2014 Issue

30 EWAP CAtArACt/IOL Pseudophakic dysphotopsia June 2014 FAM Han Bor, MD Senior Consultant & Head, Cataract & Implant Service, The Eye Institute @ Tan Tock Seng Hospital 11 Jalan Tan Tok Seng, Singapore 308411 Tel. no. +65-6357-7726 Fax no. +65-6357-7718 famhb@singnet.com.sg D ysphotopsia or photic phenomena is a general term to describe light-related visual phenomena encountered by a subject. It includes a broad range of visual phenomena such as glare, halos, flashes, etc. Some of these visual phenomena are more specific in nature while others are more general. There are many causes of dysphotopsia. Aggravated higher order aberrations, changes in optical media properties in the eyes from various causes, etc. may cause dysphotopsia. Lately, IOL-related dysphotopsia has been an increasingly recognized problem after IOL implantation. These symptoms can be broadly divided into positive (lighted) or negative (dark). It occurs in about 20% of post-cataract patients. Fortunately, most of these symptoms are mild and do not affect patients’ daily activities. Most of these symptoms resolve with time. Negative dysphotopsia is usually more bothersome and persistent than positive dysphotopsia. It is also more difficult to eliminate. IOL-related dysphotopsia may be more commonly associated with truncated (square) edge, high refractive index, high reflectance material, and flatter anterior surface IOLs. The actual cause, however, is much more complex, involving a combination of the factors in the capsular bag–IOL complex. The management of dysphotopsia can be divided into 2 categories: ascertaining the cause of dysphotopsia and controlling the dysphotopsia. Ascertaining the cause of dysphotopsia can be a time-consuming process. The nature of the dysphotopsia may provide important clues to the cause of dysphotopsia. Hence, getting a good history on the nature dysphotopsia is very important. Glare and halos in multifocal IOLs are common and most patients can adapt to these symptoms. Early intervention in these cases is usually unnecessary. Other non-IOL causes of dysphotopsia such as refractive errors, severe dry eye, corneal scar, etc., should be considered and managed appropriately. As for IOL-related dysphotopsia, various options have been suggested. Fortunately, most of these symptoms are mild and resolve with time. If it is very symptomatic, a trial of pharmacologic miosis may be instituted. If that fails, YAG capsulotomy of the anterior nasal capsule may be helpful. Interventional alternatives include reverse optic capture where the optic of the IOL is captured anteriorly by the circular anterior capsulorhexis; IOL exchange with a round-edge IOL or more definitely piggyback IOL in the sulcus. Editors’ note: Dr. Fam has no financial interests related to his comments. Views from Asia-Pacific AWARDS CEREMONY