Influence to anterior chamber pressure by injection of microincision intraocular lenses

Poster Details

First Author: N.Gotoh JAPAN

Co Author(s):    H. Matsushima   T. Senoo           

Abstract Details

Purpose:

Transient high pressures have been shown to cause disc cupping and temporary depression of the visual field, which is greater in eyes with glaucoma. On one hand, microincison caratact surgery (MICS) is subject to considerable research. However, intraocular pressure during intraocular lens (IOL) implantation is not really investigated. In this study, we compared anterior chamber pressure during insertion of some types of microincision IOLs using by different types of injectors.

Setting:

N/A

Methods:

After lens extraction in porcine eye, the anterior chamber pressure was controlled in 15mmHg with injecting Healon Viscoelastic (AMO) before IOL imlpantation. Microincision IOLs (Tecnis-1 ZCB00(AMO), AcrySof IQ SN60WF(Alcon), iMics1 251(HOYA)) were inserted through 2.40mm or 2.65mm corneal incision using different insertion techniques (cartridge-insertion or wound-assisted) and different plunger types (dial or push). Pressure transducer placed in the anterior chamber measured real-time pressure changes (10 reading per second) during IOL implantation.

Results:

The peak of anterior cumber pressures during IOL implantation in 2.65mm incision (Tecnis-1=92.3+/-12.8mmHg, AcrySof IQ=50.7+/-9.9mmHg) were smaller than the pressures of IOL implantation in 2.40mm incision (Tecnis-1= 99.1+/-24.6mmHg, AcrySof IQ= 102.8+/-23.8mmHg). However, the pressure of iMics1 implantation (41.7+/-3.4mmHg) was not increased in 2.40mm incision because the cartridge contains a slit at its tip. The pressures during injection of IOL by cartridge-insertion technique (Tecnis-1= 99.1+/-24.6mmHg, AcrySof IQ= 102.8+/-23.8mmHg) were much smaller than the pressures of IOL implantation by wound-assisted technique (Tecnis-1=92.3+/-12.8mmHg, AcrySof IQ=50.7+/-9.9mmHg, iMics1=41.7+/-3.4mmHg). Under the dial type injector, the peaks of pressure were soon after the IOL implantation and then underwent a gradual decrease in pressures. Under the push type injector, the pressures were increased by pushing on plunger and were decreased rapidly with IOL insertion.

Conclusions:

The anterior chamber pressure during IOL implantation was influenced by incision size, insertion technique, and plunger type. In MICS, elevation of intraocular pressure during IOL implantation may be controlled by considering these influence factors in eyes with glaucoma and optic nerve neuropathy. FINANCIAL DISCLOSURE?: No