A prospective pilot study using a low power piggy-back toric implantable Collamer lens to correct residual refractive...

To assess whether residual refractive error after in-the-bag multifocal intraocular lens (mIOL) implantation can efficaciously and safely be corrected with a piggy-back low power Visian Toric Implantable Collamer Lens^® (VTICL, STAAR Surgical) placed in the ciliary sulcus.

Twenty-four eyes of 23 patients (mean age: 57.5 years) with diminished uncorrected distance visual acuity (UDVA) of ≥2 lines due to residual refractive error after mIOL implantation were included in the study. VTICL size was calculated using the standard STAAR Visian ICL calculation software for phakic eyes. Postoperative study visits (1 day, 1 week, 3 months and 6 months after VTICL implantation) included UDVA, corrected distance visual acuity (CDVA), VTICL axis alignment, vault (space between mIOL and VTICL), IOP and documentation of adverse events.

At 6 months, mean UDVA (logMAR) increased from 0.26 preoperatively to -0.01 (P<0.001) while mean CDVA remained unchanged. Mean VTICL misalignment from the preoperative target axis was 5.3° and mean vault was 1385 µm. In the initial phase of the study, 2 VTICL had to be exchanged due to oversizing.

Piggy-back low power VTICL can efficaciously correct residual refractive error after mIOL implantation and significantly increase UDVA. Advantages of this novel surgical approach include: VTICL availability in small diopter steps, no significant surgical-induced astigmatism, atraumatic and reversible procedure.