The Effect of Myopic Optical Defocus on the Humphrey Matrix 30-2 Test

The Humphery Matrix (Zeiss, Dublin, California, USA; in cooperation with Welch Allyn, Skaneateles, New York, USA), which is a recently developed version of FDT perimetry, showed more improved technology to detect early glaucomatous damage. The user's guide for the Humphrey Matrix (Humphrey® matrix visual field instrument user's guide. Zeiss, Dublin, California, USA; in cooperation with Welch Allyn, Skaneateles, New York, USA; 2003) suggests that myopic refractive errors more than -3.0 D need to be corrected before the 30-2 test. However, the proper correction of the optical defocus is not always easy because of a lack of trial frame.

The purpose of the present study is twofold. At first, the influence of the low-grade myopia on the Humphery Matrix 30-2 test will be evaluated and compared to the effect of moderate-grade myopia. Secondly, the influence of myopic optical defocus and the glaucomatous visual field damage on the pattern deviation plot change according to the severity of glaucomatous visual field damage will be estimated.

Inclusion criteria

• intra-ocular pressure 23 or higher
• suspicious glaucomatous optic disc change
• suspicious defect of retinal nerve fiber layer
• or eyes with various degrees of glaucoma

Exclusion criteria

• a high myopic eye (SE more than -6.0 D)
• moderate to severe cataract
• evidence of diabetic or hypertensive retinopathy
• macular disease
• intra-ocular inflammation
• history of intraocular surgery and any other ocular lesion that could have an influence on the perimetry result