Changes of parameters for IOL calculation for patients after combined phacovitrectomy with ILM-peeling

Session Details

Session Title: Presented Poster Session: New & Interesting I

Venue: Poster Village: Pod 3

First Author: : I.Bayer GERMANY

Co Author(s): :    M. Shajari   S. Priglinger   W. Mayer   E. Vounotrypidis              

Abstract Details

Purpose:

We want to assess the occurrence and the magnitude of changes in the eye parameters which are used for IOL calculation. These include axis length (AL), anterior chamber depth (ACD), corneal diameter (WZW), corneal radii (K1,K2) and the corneal anterior and posterior surface (cornea front/back).  The objective of this study was to analyze whether these parameters changed in patients undergoing phacovitrectomy for vitreomacular pathology and cataract.

Setting:

Department of Ophthalmology, Ludwig-Maximilians-University Munich, Germany

Methods:

The retrospective non-randomized, single-center consecutive case series consisted data of 50 eyes of 50 patients with age-related cataract, and clinically significant vitreomacular pathology (epiretinal membrane=ERM, macular hole=MH, vitreomacular traction syndrome=VMTS) that underwent combined phacovitrectomy with ILM-peeling Objective refraction, axial length (AL), anterior chamber depth (ACD), corneal diameter (WZW), corneal radii (K1,K2) and the corneal anterior and posterior astigmatism (cornea front/back) were obtained preoperatively and 3 months after surgery. We therefore used a novel swept-source optical coherence tomography-based (SS-OCT) biometer (IOLMaster 700,Carl Zeiss Meditec,Jena,Germany). In a second step we analyzed if there is a difference between the pre- and postoperative data.

Results:

For the statistical analysis, we used the Wilcoxon signed-rank test as well as Vector analysis for the corneal surface. The evaluation revealed a statistic significant difference between the pre- and postoperative axial length(p=<0,001), the anterior chamber depth (p=<0,001) and the postoperative corneal radius K1(p=0,0004) but no statistic significant difference between the pre- and postoperative corneal diameter(p=0,3760), and corneal radiusK2(p=0,0515). Furthermore, we did a vector analysis to measure the changes in the corneal surface. The refraction showed a difference from 0,10/0,28x18 in the corneal front, a difference from 0,02/0,10x44 in the corneal back and a total difference of 0,06/0,32x31.

Conclusions:

Results indicate that there are statistic significant differences between the pre- and postoperative anterior chamber depth and the postoperative corneal radius K1 as expected through the operative procedure. Furthermore, the vectoranalysis shows a small refractive change in the corneal surface with a hyperopic shift and a reduction of the corneal astigmatism.  However, the most interesting result was a change in the axial length.

Financial Disclosure:

None