Efficacy of SLO-Microperimetry and Humphrey for evaluating macular sensitivity changes in advanced glaucoma

• Published in: Canadian journal of ophthalmology 2013-10, Vol.48 (5), p.406-412
• Main Authors: Kulkarni, Sadhana V., MD, Coupland, Stuart G., PhD, Stitt, David M., BSc, Hamilton, John, BSc, COMT, Brownstein, Jonathan J., BSc, Damji, Karim F., MD, FRCSC, MBA
• Format: Article
• Language: English
• Subjects: Aged; Cohort Studies; False Positive Reactions; Female; Fixation, Ocular - physiology; Glaucoma, Open-Angle - diagnosis; Glaucoma, Open-Angle - physiopathology; Humans; Internal Medicine; Male; Ophthalmology; Ophthalmoscopes; Pilot Projects; Predictive Value of Tests; Prospective Studies; Retina - physiopathology; Scotoma - diagnosis; Scotoma - physiopathology; Sensory Thresholds; Visual Field Tests - methods; Visual Fields - physiology
• ISSN: 0008-4182; 1715-3360
• DOI: 10.1016/j.jcjo.2013.08.001

Abstract Objective To compare the efficacy of scanning laser ophthalmoscope microperimetry (SLO-MP) and Humphrey visual fields in detecting macular sensitivity changes in advanced glaucoma. Design Prospective cohort study. Participants 25 patients with advanced primary open angle glaucoma and 2 consecutive abnormal Humphrey 10-2 SITA Standard visual field tests. Methods Thirty-six eyes of 25 patients with 2 consecutive abnormal Humphrey 10-2 SITA Standard (H10) visual fields were retested with a modified 10-2 SLO-MP within 3 months of the last reliable H10. A standardized grid was used to mark the macula. Primary outcome was change in mean macular sensitivity (dB; H10 and SLO-MP) in relation to mean macular retinal nerve fibre layer (RNFL) thickness (µm) by SLO- optical coherence tomography (SLO-OCT). Secondary outcome was comparison of reliability indices for both tests. Linear regression was used for analysis. Results Mean macular sensitivity was significantly lower in SLO-MP (9.33 ± 3.37 dB) than H10 (18.83 ± 6.46 dB; p < 0.0001). Mean macular RNFL thickness correlated significantly with retinal sensitivity by both SLO-MP ( r = 0.39, p < 0.02) and H10 ( r = 0.37, p < 0.03). Fixation losses were better controlled in SLO-MP (0.38 ± 1.1) than H10 (4.28 ± 7.9; p = 0.008). False-positive responses were similar (SLO-MP: 2.25 ± 4.53, H10: 1.78 ± 3.33; p = 0.80). A statistically significant difference was noted in the false-negative responses (SLO-MP: 26.87 ± 25.24, H10: 5.33 ± 9.70; p < 0.0001). Conclusions Macular sensitivity determined by both H10 and SLO-MP correlates significantly with mean macular RNFL thickness measured by SLO-OCT. Precise localization of the macula in SLO-MP results in lower fixation losses. Detection of denser field defects by SLO-MP results in higher false-negative responses. A larger sample size is needed to further study the value of this diagnostic tool.