Abstract
Purpose: :
The Menicon Z rigid gas permeable (RGP) contact lens material (tisilfocon A) has the highest oxygen transmissibility (Dk) value of any lens in this class. To our knowledge there is no published literature documenting the success of this material in fitting contact lenses to highly irregular and diseased corneas.
Methods: :
A retrospective chart review of 34 consecutive patients (56 eyes) who had worn the Menicon Z RGP lens were reviewed. All patients had some form of corneal pathology and were fitted in a single tertiary care hospital based contact lens service.
Results: :
Menicon Z contact lenses were fit to 28 eyes of 17 patients with Keratoconus of varying stages of progression, 24 eyes of 18 patients after corneal surgery (PK, DALK, RK, or AK), 1 eye with ocular cicatricial pemphigoid and 2 eyes of 1 patient with chronic staphylococcal blepharo-keratoconjuncitivitis. Treatment goals included limitation of neovascularization and edema, comfort, and preserved visual acuity. In the KC group, there was a 75% (21/28 eyes) success rate as measured by treatment goals. Mean duration of wear for successful patients is 2.5 years (0.5-5 yrs). 7.1% (2/28 eyes) had epithelial defects, 7.1% (2/28 eyes) had unacceptable fits, and 10.7% (3/28 eyes) experienced material incompatibility. Only 7.1% (2/28 eyes) failed directly due to inability of the Menicon Z material to perform adequately while another material was acceptable. In the irregular surface group (surgical and ocular surface disease), there was a 74.1% (20/27 eyes) success rate. Mean duration of wear for successful patients in this group is 2.79 years (3 mo - 7 yrs). 3.7% (1/27eyes) experienced discomfort, 11.1% (3/27 eyes) had unacceptables fits , 7.4% (2/27 eyes) experienced material incompatibility, and 3.7% (1/27) experienced intolerance to all lenses. All eyes met corneal physiology treatment goals. Only 3.7% (1/27 eyes) failed directly due to inability of the Menicon Z material to perform adequately while another material was acceptable.
Conclusions: :
The Menicon Z RGP hyper Dk lens material (tisilfocon A) effectively maintains corneal physiology and visual acuity for KC and irregular corneal surfaces. In this series of patients with complicated corneal disease, the majority of failures were due to design issues and discomfort not related to the Menicon Z material. The Menicon Z material was inadequate in only 5.45% of eyes, while another RGP material was successful. The majority of irregular corneas eyes in a tertiary care center can be successfully fit with the Menicon Z RGP material for visual rehabilitation.
Keywords: contact lens • keratoconus • clinical (human) or epidemiologic studies: outcomes/complications