Long Term Safety And Efficacy Outcomes Of Anterior Chamber Intraocular Lens Implantation: A Retrospective Single Centre Cohort Study

Routine cataract surgery involves implantation of an intraocular lens (IOL) into the posterior chamber. Rarely in complex or complicated cataract surgery, IOLs can be placed in the anterior chamber (AC-IOL). Over the past decade, there has been a trend towards fixating the IOL using iris or sclera, as it has been postulated that AC-IOL use is associated with a higher risk of complications (e.g. inflammation, raised intraocular pressure or corneal decompensation). This retrospective study therefore seeks to examine the long-term outcome and establish audit standards from our patient cohort of those who had an AC-IOL implanted over the past 13 years.

Gloucestershire Hospitals NHS Foundation Trust

All available MediSight data (since 2012) in Gloucestershire Hospitals NHS Foundation Trust pertaining to patients who have had implantation of Alcon MTAxU0 AC-IOLs were extracted. 16 eyes were excluded owing to insufficient follow-up duration (defined as <6 months). This left n = 33 eyes to be included in this study, which were followed-up for a total duration of between 6 months – 12 years (mean = 48 months). Subjects included 11 males and 22 females, with an average age of 77 years old at the time of surgery (range 17-93 years old). Where available, the following outcome metrics were extracted: visual acuity, intra-ocular pressure (IOP), corneal clarity, refraction, associated complications and any further surgery.

Pre-existing conditions included pseudoexfoliation (5/33) and connective tissue disorders (3/33). AC-IOL implantation proceeded following zonular dialysis (21/33), posterior capsule rupture (12/33), crystalline lens subluxation (4/33), aphakia (2/33), and IOL dislocation (2/33), with insertion complicated by Descemet’s membrane detachment (2/33). By week 1, 3/33 eyes were >25 mmHg, whilst 2/33 eyes were hypotonous (<5 mmHg). Late complications included: reduced corneal clarity (7/33), chronic inflammation (5/33), giant cells on IOL (2/33), pseudophakic bullous keratopathy (1/33), AC-IOL dislocation (1/33), endophthalmitis (1/33), raised IOP (1/33). The final mean BCVA was 0.65 (range 0.00 – NPL), with 17/33 eyes achieving 0.50 or better. 

AC-IOL placement in the setting of prior complex/complicated cataract surgery may offer effective long term visual outcomes with a low rate of complications. Monitoring of intraocular pressure and corneal clarity (and, where possible, endothelial cell density) should constitute routine clinical practice in establishing audit standards, when such lenses are used.