Abstract
Purpose :
To quantitatively assess the magnitude of toric intraocular lens (IOL) rotation using a custom photographic method compared to the traditional slit-lamp method.
Methods :
IOL rotation was evaluated as part of a large prospective, multicenter, single-arm, open-label clinical study in which 200 eyes were implanted with a toric IOL. For the photographic method, all eyes were evaluated by two independent masked analysts using a validated, custom-developed analysis software program. This software featured automatic image alignment based on ocular landmarks photographed intraoperatively with the surgical microscope and postoperatively with a slit-lamp camera. In addition, the slit-lamp examination was used to determine lens axis orientation by rotating the beam to align with the toric lens markings. Lens rotation was defined as the absolute difference between IOL axis at the end of surgery and IOL axis measured using the photographic or slit-lamp method at the 1-day, 1-wk, and 3-mo visits.
Results :
The mean lens rotation measured at the 1-day, 1-wk, and 3-mo visits with the photographic method was 0.82±1.00°, 0.85±0.92°, and 0.94±0.71°, respectively; the slit-lamp method was 2.98±3.60°, 3.14±3.54°, and 3.45±3.78°, respectively. The maximum rotation measured with the photographic method was 8.32° and with the slit-lamp method was 25.0°. At the 3-mo visit, 100% of IOL rotations using the photographic method and 95.5% using the slit-lamp method were measured to be ≤10°. There was a greater discrepancy between methods, 100% with the photographic method and 80.5% with the slit-lamp method, for reporting IOL rotations within ≤5°.
Conclusions :
The photographic method demonstrated a greater sensitivity for detecting toric IOL rotation and was more likely to detect small degrees of IOL rotation. However, it may be difficult to implement as part of standard clinical care. This analysis may suggest a tendency for clinicians to over-estimate IOL rotation, especially small misalignments, using the slit-lamp method.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.