Patient Perception of Glaucomatous Visual Field Loss Associated with Disease Severity

Abstract

 

Purpose

 

To investigate patient perception of glaucomatous visual field loss and its association with glaucoma severity using the Amsler grid test.

 

Methods

 

Glaucoma patients with abnormal 10-2 Humphrey visual field (VF) tests within the previous 4 months were enrolled consecutively. Black-on-white Amsler grid tests were administered for each eligible eye at a distance of 30 cm. Patients were asked to outline any perceived scotomas (areas with missing or blurred grid lines) and then describe verbally their perception of the scotomas. Responses and descriptions used by patients were recorded in their own words. Descriptor frequency and association of descriptors with 10-2 VF mean deviation (MD) were analyzed.

 

Results

 

We included 88 eyes of 50 patients (10-2 VF MD = -11.74±8.69 dB; mean age = 67±11 years). Patients used a total of 40 different descriptors (Table 1). Descriptors were classified into categories that incorporated similar effects, resulting in 6 overarching categories: Missing (M), White (W), Blurry (B), Gray (G), Dark/Black (K), and Not aware (N) (Table 1). The frequency order was: M (40%), B (33%), W (27%), G (24%), K (5%), and N (19%). Mean number of descriptor categories per eye was 1.47±0.71 (range, 1-3). Eyes with greater number of descriptor categories had worse VF MD (p<0.001) (Fig 1A). After Missing (M) and Blurry (B) were combined with White (W) and Gray (G) to generate categories ‘MW’ and ‘BG,’ respectively, each eye naturally sorted into one of the following 5 groups: MW (27 eyes; 31%), BG (21 eyes; 24%), combined MW and BG (MW+BG; 19 eyes; 21%), K (4 eyes; 5%), and N (17 eyes; 19%). The MD severity order was K (-21.55±10.44 dB), MW+BG (-16.51±10.32 dB), MW (-12.41±6.79 dB), BG (-11.05±7.03 dB), and N (-3.91±4.05 dB) (p<0.001): ‘Not aware (N)’ eyes had significantly better VF MD than all the other categories (p<0.005), and ‘Dark/Black (K)’ eyes had significantly worse VF MD than all categories (p<0.030) except ‘MW+BG’ eyes (p=0.227) (Fig 1B).

 

Conclusions

 

Patient perception of glaucomatous VF loss within the central 10 degrees varied considerably, with ~1 of 5 eyes recognizing no VF loss and ~1 of 20 eyes perceiving scotomas as dark or black areas. Eyes with greater number of descriptor categories had more advanced glaucoma, and glaucoma severity tendency was ‘Dark/Black’ < other descriptors < ‘Not Aware.’

 

 

 

Keywords: 758 visual fields • 641 perception • 496 detection