Posters

On so-called ‘over-correction' symptoms after LASIK

Poster Details

First Author: K.Okuyama JAPAN

Co Author(s):                  

Abstract Details

Purpose:

Try and clarify the actual cause of what has been accused as ‘over-correction' symptoms after Lasik. In 2013,the Consumer Affairs Agency (CAA) of Japan said on Dec. 4th that eighty cases of health hazards by Lasik has been reported so far, the data based on what has been accumulated by the National Consumer Affairs Center (NCAC) of Japan since 2009. According to CAA, the largest number of claims, some twenty cases or more, are seem-likes of over-correction, causing headache and nausea as a result of Lasik. A close look into CAA's report, though, reveals a fundamental flaw. No data is shown regarding hypermetropia after ‘over-correction', and refractometry data resembles emmetropia. For that very reason, most patients are likely to be diagnosed OK as far as ophthalmology is concerned, or even sent, after Lasik, to psychiatrist or neurologist, and they have been notoriously entitled as ‘Lasik Sufferers'. It was those people who ran into NCAC for help, in the reality.

Setting:

Studied at the Sangubashi Eye Clinic, Tokyo, Japan, by MD Kodo OKUYAMA in 2014..

Methods:

Retrospective study on Keratotopograms; of four patients, two male and two female, in their thirties to fifties. One year or more have already passed after each operation using either the Profile 500 of the Fyodrov Institute for the PRK, or SVS Apex Plus of the Summit Technology for Lasik. Microkeratome Chiron Hansatome, Keratotopography TMSⅡ-N and other routine examinations attending pre and post refractive surgery. Retrospective study on Keratotopograms of; Lasik and PRK, Case 1; both eyes with SE-3D / Case 2; both eyes with SE-11D Keratotopograms of Case 3; both eyes underwent Lasik with SE-4D. Keratotopograms of Case 4; both eyes underwent PRK with SE-4D. Of Case 5; which underwent PRK with SE-16D. According to CAA's web survey, eighty cases of Lasik are said to have underwent health hazards since 2009, and the largest number of claims, some twenty cases or more, are related to ‘over-correction' of sight. Though the tendency of which was never really the case while PRK was the mainstream before 2009, so the comparison of PRK in contrast to Lasik might help understand the discrepancy.

Results:

For each case of Keratotopogram shows that after PRK, wider transitional zone is born, more so than after Lasik. Detailed examinations are now under way, on accommodation's heavy-loading probabilities, for the future chance to elaborate on the matter, though.

Conclusions:

At the core of what has been called ‘over-correction' symptoms after Lasik, hides a question of over-loading of accommodation, as the keratotopgraphic analyzer shows, because of a narrower transitional zone after PRK abrasion. Taking Lasik flap of 160 microns from cornea with thickness of 500 microns means, most commonly, 360 microns still remains. And the remaining lesser thickness narrows transitional zone, resulting in heavy over-loading of accommodation, so the greater chances of headache, nausea, dry eye and other unidentified complaints are likely to be seen. Further more study must be made, however, on the accommodation and its over-loading probabilities. FINANCIAL INTEREST: NONE