Optimizing Suboptimal Results Following Cataract Surgery by Priya Narang William B. Trattler

Author:Priya Narang,William B. Trattler
Language: eng
Format: epub
Publisher: Thieme Medical Publishing Inc.
Published: 2018-10-04T00:00:00+00:00

13.4 Intraocular Lens Selection

IOL selection is complex in the presence of corneal endothelial disease, due to a difficulty in gaining accurate preoperative measurements, as well as the uncertain effect on corneal function and therefore power postoperatively. In addition, if the patient goes on to require EK, the corneal power will further change, and that change will be unpredictable.

General considerations include the type of IOL, the material of the IOL, and the power. Monofocal IOLs are usually appropriate. Multifocal IOLs and extended depth of focus IOLs are generally not recommended for patients with endothelial cell compromise. Toric IOLs may have a place, and should be considered on a case-by-case basis depending on accuracy and reproducibility of measurements. Hydrophilic material is known to have the potential to opacify when it comes into contact with air or gas. There have been several cases reported of IOL opacity post-EK in patients with hydrophilic IOLs.4 It is therefore recommended to avoid hydrophilic IOLs in patients who may go on to require EK in the future.

EK is associated with a hyperopic shift, of varying magnitude. The reason for this is multifactorial, and includes the addition of a concave lenticule (in the case of DSAEK), and an unpredictable amount of corneal deturgescence with Descemet’s stripping automated endothelial keratoplasty (DSAEK) and DM endothelial keratoplasty (DMEK). Up to 1.5-diopter hyperopic shift in spherical equivalent has been reported after DSAEK,5 and a lesser shift after ultrathin (UT) DSAEK6 and DMEK.7 The range is great, and predictability is difficult. Common targets for patients undergoing combined cataract surgery and EK would be −0.5 - −0.75 for DMEK and −0.75 - −1.5D for DSAEK or UT DSAEK. If the patient is undergoing cataract surgery alone, this hyperopic shift should still be taken into account, in case EK is required in the future. Surgeons should then aim to reduce the chance of postoperative hypermetropia where possible, by selecting a myopic target.

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