12/4/2015 Introduction � Traditional visual field is done at doctor’s office � High cost � Labor intensive � Time consuming � Would it be possible to test visual field at home? � Low or no cost Ying Han, MD, Ph.D � Convenient to patients Associate Professor of Ophthamology � Possible screening tool University of California, San Francisco Introduction � Peristat, a free novel web-based perimetry � It can be done on any computer with a standard 17 inch or larger screen via internet connection at www.keepyoursight.org 1 � It systematically maps out 24 degrees of visual field function. � It takes ~5 mins to finish the test 1
12/4/2015 Testing condition Parameters � The target size is 3 mm in diameter and presents within � In a dark room 6-degree apart. � The brightness and contrast sensitivity of the � Each target is presented for 0.2 seconds, and the patient monitor should be adjusted to 50% of maximal value is allowed an additional grace period of 1.8 seconds to of brightness and contrast sensitivity respond. � One eye is covered � Points were tested at three stimulus brightness with a range of 1odB � Test distance is ~ 18-inches � It ensures reliability through measurements of fixation losses, false positives, and false negatives. Example – control subject HVF Peristat 2
12/4/2015 Example Left eye Right eye Left eye Right eye Example – moderate glaucoma Example – severe glaucoma HVF Peristat HVF Peristat 3
12/4/2015 A Clinic study on Peristat Methods � To study the correlation between Peristat and � Inclusion criteria: Humphrey visual field (HVF). � Diagnosis of glaucoma with glaucomatous optic nerve change and abnormal HVF. � Corrected visual acuity in tested eye better than 20/60. � To evaluate sensitivity and specificity of Peristat for � Without other ocular or neurological causes of visual detecting glaucoma. field defects. � Can reliably perform HVF. Methods Results: Demographic Comparison � All subjects performed 24-2 SITA-standard HVF and Glaucoma Patients Control P value Peristat in the office. (63) (12) 64.8 ± 14.6 61.1 ± 10.7 � A reliable field for both tests was defined as fixation Age (years) 0.2 loss, false positive and false negative ≤ 33%. Gender Female: 32 (51%) Female: 7 (58%) 0.36 Male: 31 (49%) Male: 5 (42%) � Mild, moderate and severe glaucoma were defined by 0.24 ± 1.6 0.17 ± 1.4 Visual Acuity (logMAR) 0.54 Hodapp-Anderson-Parrish criterion. 4
12/4/2015 Methods Results: Correlation between HVF and Peristat 60 Abnormal HVF points Total number of abnormal points on HVF pattern � 50 deviation and total number of abnormal Peristat 40 points were counted. Spearman’s Rank correlation 30 was analyzed. 20 ROC analysis to evaluate the Peristat for detecting � 10 mild, moderate and severe glaucoma. 0 0 10 20 30 40 50 Abnormal Peristat points Correlation Coefficient (r) = 0.70 (p<0.0001) Results: ROC for patients with mild glaucoma Results: ROC for patients with moderate glaucoma Area under curve Area under curve Total Points Moderate glaucoma Total Points Mild glaucoma Light Grey 0.87 Light Grey 0.85 Dark Grey 0.88 Dark Grey 0.77 Black 0.86 Black 0.74 P-value comparing 3 P =0.57 P-value comparing 3 P =0.004 curves curves 5
12/4/2015 Results: ROC for patients with moderate and Results: ROC for patients with severe glaucoma severe glaucoma Area under curve Total Points Severe glaucoma Sensitivity = 80% Light Grey 0.90 Specificity = 91% Dark Grey 0.91 Black 0.88 P-value comparing 3 P =0.24 Area under curve is 0.87-0.88 curves Conclusion Limitation and Future Studies � Online visual field (Peristat) can be performed � Test whether Peristat can be performed reliably reliably at doctor’s office. outside of doctor’s office by HVF-naïve patients. � Peristat has strong correlation with HVF. � Refining Peristat test to improve its usability. � Peristat has moderate-high sensitivity and specificity � Longitudinal study to exam whether Peristat can be to identify eyes with moderate to severe glaucoma. used to detect progression with moderate-severe � Peristat could be a good screening tool. glaucoma. 6
12/4/2015 Thank you Results � Keepyoursight � Jing Hou, MD, PhD � Consecutive seventy-seven glaucoma patients with 129 Foundation: � Shan Lin, MD eyes and 12 controls with 14 eyes were enrolled. � Sean Ianchulev, MD � Robert Stamper, MD � Sixty-three (82%) glaucoma patients with 84 eyes and 12 � Jeremy Keenan, MD controls (100%) with 14 eyes obtained reliable Peristat � Travis Porco, PhD � Stanford University tests. � Gene Lowry, MD � Robert Chang, MD � The number of eyes with mild glaucoma was 51 (60.7%). � Brian Chon, MD � Sean Wong � The number of eyes with moderate glaucoma was 18 (21.4%). � University of California, � The number of eyes with severe glaucoma was 15 (17.9%). San Francisco Results: example Results: example Light grey: -3 dB Dark grey: -6dB Peristat Peristat 7
12/4/2015 Results: example Black: -10 dB Peristat 8
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