Purpose: The aim of this study was to develop software for the universal objective
evaluation of factors influencing intraocular correction of astigmatism, such as decentration,
tilt, axial position and angular orientation the toric intraocular lens (IOL).
Patients and Methods: Software was developed using the MS Visual Studio environment.
The analysis was presented using images of 67 eyes with an implanted IOLs of the SN6ATx
model series. Decentration and angular position of the lens were obtained from images of the
anterior segment of the eye, using a Visucam unit. Tilt was measured on tomographic images
from OCT Avanti (in meridian of highest tilt and perpendicular meridian) and preoperative
biometry parameters of eye (axial length, anterior chamber depth – ACD, ocular lens
thickness – LT, limbus diameter and mean keratometry value) including postoperative
anterior chamber depth (pACD) were measured using Lenstar LS900.
Results: Applying the software methodology to the evaluation of individual toric IOL
parameters, the following results were obtained: mean decentration 0.25 ± 0.17 mm which
was observed in 61.19% of eyes, mean misalignment to the planned axis equal to 3.8 ± 3.6
degrees, mean highest inclination equal to 3.7 ± 1.2 degrees and mean difference of pACD
and ACD was equal to 1.46 ± 0.31 mm. There was only a weak nonsignificant correlation
between preoperative ACD versus decentration and tilt of IOL or a weak significant
correlation between preoperative LT and both decentration and misalignment of IOL.
Conclusion: The use of the presented methodology for determining the positional
parameters of the toric IOL provided comparable results with the results of recent
studies. Software design can be considered as a suitable alternative to previously published techniques, with the significant advantage of the possibility of using universal
input images, their graphical editing and especially the possibility of comprehensive
analysis of all parameters.
eng
dc.format.mimetype
application/pdf
dc.language.iso
eng
dc.publisher
Dove Medical Press
dc.relation.ispartof
Clinical Ophthalmology
dc.subject
astigmatism and cataract
eng
dc.subject
toric IOL centration
eng
dc.subject
toric IOL tilt
eng
dc.subject
toric IOL axis misalignment
eng
dc.title
Evaluation of Decentration, Tilt and Angular Orientation of Toric Intraocular Lens