Comparison of new motorized injector vs manual injector for implantation of foldable intraocular lenses on wound integrity: an ASOCT study

Abstract

Purpose: To compare intraocular lens implantation using a motorized injector vs standard manual injector through a 2.2-mm clear corneal incision.

Methods: Patients underwent standard phacoemulsification using a 2.2-mm clear corneal incision. Hydrophobic acrylic aspheric intraocular lens (Acrysof SN60WF intraocular lens (IOL)) was inserted using D cartridge with manual monarch injector or autosert motorized injector. IOL safety, final incision size and wound integrity in terms of anterior and posterior wound gape, and descemet's membrane detachment were compared between the two groups at post-operative day 1 and at 1 month using Anterior Segment Optical Coherence Tomography.

Results: The study recruited 32 patients in the group I (manual injector) and 30 patients in group II (motorized injector). In group I, the final incision after IOL insertion increased by 0.12 mm (95% CI: 0.134-0.106) (P<0.0001), which was seen in 100% of the patients. In group II, the incision enlarged by 0.01 (95% CI: 0.021-0.0.001) (P=0.07) and was seen in only 6.67% of the cases. IOL nicks were seen in 9.37% of the cases in group I only. Although the incidence of descemet's membrane detachment and anterior wound gape was similar for both groups, posterior wound gape was seen more often with the manual injector in the immediate post-operative period. (P=0.018) CONCLUSION: The motorized insertion system was gentle and safe for the IOLs with lesser incidence of IOL nicks. Regarding wound safety, it caused significantly less incision enlargement and better posterior wound integrity.

Figure 1

Incision gauges used for measuring incision size.

Figure 2

Arrow showing IOL nick in periphery in a patient in which IOL implantation was done using manual injector.

Figure 3

(a) ASOCT image showing descemet membrane detachment in a patient in the manual injector group on day 1. (b) ASOCT image showing descemet membrane detachment in a patient in the motorized injector group on day 1. (c) ASOCT image showing posterior wound retraction in a patient in the manual injector group at 1 month. (d) ASOCT image showing posterior gape in a patient in the manual injector group on day 1. (e) ASOCT image showing posterior gape in a patient in the motorized injector group on day 1. Note that the incision architecture is arcuate thus imparting greater wound strength.