Prediction of functional loss in glaucoma from progressive optic disc damage.
OBJECTIVE
To evaluate the ability of progressive optic disc damage detected by assessment of longitudinal stereophotographs to predict future development of functional loss in those with suspected glaucoma.


METHODS
The study included 639 eyes of 407 patients with suspected glaucoma followed up for an average of 8.0 years with annual standard automated perimetry visual field and optic disc stereophotographs. All patients had normal and reliable standard automated perimetry results at baseline. Conversion to glaucoma was defined as development of 3 consecutive abnormal visual fields during follow-up. Presence of progressive optic disc damage was evaluated by grading longitudinally acquired simultaneous stereophotographs. Other predictive factors included age, intraocular pressure, central corneal thickness, pattern standard deviation, and baseline stereophotograph grading. Hazard ratios for predicting visual field loss were obtained by extended Cox models, with optic disc progression as a time-dependent covariate. Predictive accuracy was evaluated using a modified R(2) index.


RESULTS
Progressive optic disc damage had a hazard ratio of 25.8 (95% confidence interval, 16.0-41.7) and was the most important risk factor for development of visual field loss with an R(2) of 79%. The R(2)s for other predictive factors ranged from 6% to 26%.


CONCLUSIONS
Presence of progressive optic disc damage on stereophotographs was a highly predictive factor for future development of functional loss in glaucoma. These findings suggest the importance of careful monitoring of the optic disc appearance and a potential role for longitudinal assessment of the optic disc as an end point in clinical trials and as a reference for evaluation of diagnostic tests in glaucoma.
Medeiros
Felipe A
FA
Hamilton Glaucoma Center and Department of Ophthalmology, University of California-San Diego, La Jolla, USA. fmedeiros@eyecenter.ucsd.edu
Alencar
Luciana M
LM
Zangwill
Linda M
LM
Bowd
Christopher
C
Sample
Pamela A
PA
Weinreb
Robert N
RN
D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009798:Ocular Hypertension / Q000175:diagnosis* / Q000503:physiopathology; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis* / Q000503:physiopathology; D010781:Photography / Q000379:methods; D011446:Prospective Studies; D015203:Reproducibility of Results; D012307:Risk Factors; D014786:Vision Disorders / Q000175:diagnosis* / Q000503:physiopathology; D014792:Visual Acuity / Q000502:physiology; D058609:Visual Field Tests; D014794:Visual Fields