Posters

Risk factors for a non-optimal vault in eyes implanted with implantable collamer lenses (ICLs)

Poster Details

First Author: J.Cerpa Manito SPAIN

Co Author(s):    P. Serra   Á. Sánchez Trancón   O. Torrado   A. Baptista           

Abstract Details

Purpose:

The implantation of a phakic Implantable Collamer Lens (ICL) requires the prediction of the postoperative distance between the ICL and the crystalline lens. It is known that using preoperative parameters and lenses features (size and power) can assist in vault estimation. However, prior to this step, the clinician might have to decide whether the ICL implantation is a suitable technique for a patient. Therefore having threshold values for the preoperative parameters associated with the vault might assist in the decision process. This study aims to identify the risk factors associated with non-optimal vault sizes.

Setting:

Ophthalmology Clinic Vista Sánchez Trancón, Badajoz, Spain

Methods:

This study reports a retrospective case series of 360 eyes (1eye-1patient) operated between Dec/2012—Dec/2017, with implantation of myopic ICL (EVO-V4c, STAAR Surgical Co. Monrovia, CA, USA). Scheimpflug tomography was used for measuring the White-to-white(WTW), Central keratometry (KC) and central corneal thickness (CCT). Anterior-segment optical coherence tomography (AS-OCT Visante) applied for measuring the iridocorneal angle-to-angle (ATA), internal anterior chamber (ACQ), crystalline lens elevation (CLE), iridocorneal angle (ACA) and vault. The eyes were divided into low (OVG: ≤250µm), optimal(OVG: 250-1000 µm) and high(HVG: ≥1000 µm) vault groups. Multinomial logistic regression (MLR) was used to find the non-optimal vault predictors.

Results:

Eyes in the HVG were younger and had higher ICL size-ATA differences (ICL-ATA) compared to the OVG and LVG. The LVG had higher CLE and less myopic spherical equivalent (SE) than the OVG and HVG. Vaults were higher in deeper ACQ. MLR found CLE, ICL-ATA , age, SE and lens size as contributing factors for non-optimal vaults (pseudo R-squared=0.39). Increased CLE (Odds-Ratio:1.01) and less myopic ICL SE (OR:1.22) contributed to low vaults. Larger ICL-ATA (OR:41.29) and the 13.7mm lens (OR:7.08) were risk factors for a high vault, whereas less myopic SE (OR:0.85) and older age(OR:0.92) were protective factors.

Conclusions:

High CLE and low myopic power are risk factors for presenting a low vault, suggesting that relationship between the ICL sagittal depth and the CLE plays an important role in the vault size. On the opposite direction, ICL-ATA is the major contributor for high vault indicating that eyes with average CLE the compression induced by the excessive ICL size is the main contributor for the vault. This relationship is more critical in higher myopic SE and when 13.7mm lenses are used. The present findings allow clinicians to have a critical view on the preoperative parameters.

Financial Disclosure:

... is employed by a for-profit company with an interest in the subject of the presentation