Abstract
Purpose: :
Cataract surgery is the most commonly performed ambulatory surgery in the United States, with over one million intraocular lenses inserted each year. There have been reports of iatrogenic surface aberrations (ISAs) on intraocular lenses in literature and anecdote despite following manufacturer recommendations for lens loading and implantation. The effects of ISAs on patient vision have not been well characterized or reported. We surmised that ISAs are in fact detectable by patients under certain lighting conditions, although ISAs are unlikely to diminish overall visual function. The aim of this study is to determine if patients have visual symptoms from ISAs and to document if visual function is compromised.
Methods: :
A prospective single-center study was performed on patients status-post intraocular lens implantation. Under a slit lamp, intraocular lenses were examined for any ISAs. The length, position and angle of patient ISAs were documented. Patients were asked to record their visual observations at various distances while staring at a pinpoint light source under scotopic conditions. The patients also completed the National Eye Institute Visual Functioning Questionnaire 25 (NEI VFQ-25) to document visual health.
Results: :
Thirteen patients status-post intraocular lens implantation were recruited for this prospective single-center pilot study. Of the seventeen intraocular lenses observed under slit-lamp, ten contained an ISA and seven were pristine. The average length of the ISAs was 2.38 mm. The average angle difference calculated between observed scratch and patient documented streak angle was found to be 91.1 degrees (SD = 12.8). Patients with intraocular lens surface aberrations scored 93.1 (SD = 6.8) on the composite score of their questionnaires, patients without lens aberrations scored 95.9 (SD = 4.5).
Conclusions: :
Preliminary data suggests that all patients with ISAs (n=10) were able to detect visual aberrations under the study conditions, as opposed to none of the control group (n=7). As predicted, the ISAs manifest as broad streaks perpendicular in angle to their associated intraocular lens surface aberration. In conclusion, iatrogenic lens aberrations on intraocular lenses were appreciable under scotopic conditions. However, patients rarely complain of decreased visual acuity or dysphotopsia under normal circumstance.
Keywords: intraocular lens • cataract • visual acuity