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Evaluation of Visual Field and Imaging Outcomes for Glaucoma Clinical Trials (An American Ophthalomological Society Thesis)

Garway-Heath, D. F., Quartilho, A., Prah, P. , Crabb, D. P. ORCID: 0000-0001-8754-3902, Cheng, Q. & Zhu, H. (2017). Evaluation of Visual Field and Imaging Outcomes for Glaucoma Clinical Trials (An American Ophthalomological Society Thesis). Transactions of the American Ophthalmological Society, 115, T4-1-T4-23-.


PURPOSE: To evaluate the ability of various visual field (VF) analysis methods to discriminate treatment groups in glaucoma clinical trials and establish the value of time-domain optical coherence tomography (TD OCT) imaging as an additional outcome.

METHODS: VFs and retinal nerve fibre layer thickness (RNFLT) measurements (acquired by TD OCT) from 373 glaucoma patients in the UK Glaucoma Treatment Study (UKGTS) at up to 11 scheduled visits over a 2 year interval formed the cohort to assess the sensitivity of progression analysis methods. Specificity was assessed in 78 glaucoma patients with up to 11 repeated VF and OCT RNFLT measurements over a 3 month interval. Growth curve models assessed the difference in VF and RNFLT rate of change between treatment groups. Incident progression was identified by 3 VF-based methods: Guided Progression Analysis (GPA), 'ANSWERS' and 'PoPLR', and one based on VFs and RNFLT: 'sANSWERS'. Sensitivity, specificity and discrimination between treatment groups were evaluated.

RESULTS: The rate of VF change was significantly faster in the placebo, compared to active treatment, group (-0.29 vs +0.03 dB/year, P<.001); the rate of RNFLT change was not different (-1.7 vs -1.1 dB/year, P=.14). After 18 months and at 95% specificity, the sensitivity of ANSWERS and PoPLR was similar (35%); sANSWERS achieved a sensitivity of 70%. GPA, ANSWERS and PoPLR discriminated treatment groups with similar statistical significance; sANSWERS did not discriminate treatment groups.

CONCLUSIONS: Although the VF progression-detection method including VF and RNFLT measurements is more sensitive, it does not improve discrimination between treatment arms.

Publication Type: Article
Additional Information: © 2017 by the American Ophthalmological Society. This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
Publisher Keywords: Aged; Aged, 80 and over; Disease Progression; Female; Follow-Up Studies; Glaucoma; Humans; Intraocular Pressure; Male; Middle Aged; Ophthalmology; Retinal Ganglion Cells; Societies, Medical; Tomography, Optical Coherence; United States; Visual Field Tests; Visual Fields
Subjects: R Medicine > RE Ophthalmology
Departments: School of Health & Psychological Sciences > Optometry & Visual Sciences
SWORD Depositor:
[thumbnail of AOS thesis Revised 23.06.17.pdf]
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