Scanning laser polarimetry for measurement of retinal nerve fiber layer in absolute, advanced and early glaucoma.
BACKGROUND
To detect differences in retinal nerve fiber layer (RNFL) measurements in absolute, advanced and early glaucoma with scanning laser polarimetry (The Nerve Fiber Analyzer GDx), and to assess the usefulness and limitations of this technique for longitudinal follow-up of glaucoma patients.


METHODS
This is a prospective, cross-sectional study. Twenty-one eyes of 21 patients with absolute glaucoma, twenty-six eyes of 26 patients with advanced glaucoma and twenty-four eyes of 24 patients with early glaucoma were imaged using scanning laser polarimetry. The twelve standard GDx measurement parameters were compared using ANOVA (analysis of variance) and the Tukey test.


RESULTS
No significant differences were demonstrated for any of the twelve GDx measurement parameters between absolute and advanced glaucoma cases. There were significant differences for some GDx parameters, including the GDx number (p < 0.0001) superior ratio (p < 0.0001), inferior ratio (p < 0.0001), superior/nasal ratio (p < 0.0001), maximum modulation (p < 0.0001), ellipse modulation (p < 0.0001) and inferior average (p = 0.001) between early and advanced glaucoma, and, between early and absolute glaucoma. Significant differences were demonstrated for the superior average (p = 0.01) parameter between early and absolute glaucoma, but not between early and advanced glaucoma.


CONCLUSIONS
For follow-up of glaucoma progression, RNFL measurements using scanning laser polarimetry are more useful in the early stage than in the advanced stage.
Tsai
Jen-Chia
JC
Department of Ophthalmology, Chang Gung Memorial Hospital, Kaohsiung, Medicine of School, Chang Gung University, Taiwan. tsai4118@ms26.hinet.net
Chang
Hsueh-Wen
HW
Teng
Mei-Ching
MC
Lin
Pei-Wen
PW
Lai
Ing-Chou
IC
D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000175:diagnosis*; D006801:Humans; D007834:Lasers; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D011446:Prospective Studies; D012160:Retina / Q000473:pathology*