1 / 12

Comparison of Pupillometer With Pupillometry Function of Binocular Free-Viewing Autorefractor

Comparison of Pupillometer With Pupillometry Function of Binocular Free-Viewing Autorefractor. Charles D Cohn, MD; Jay C Bradley, MD; Peter W Wu, BS; Sandra M. Brown, MD The authors have no financial interest in the subject matter of this poster. Background.

kovit
Download Presentation

Comparison of Pupillometer With Pupillometry Function of Binocular Free-Viewing Autorefractor

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Comparison of Pupillometer With Pupillometry Function of Binocular Free-Viewing Autorefractor Charles D Cohn, MD; Jay C Bradley, MD; Peter W Wu, BS; Sandra M. Brown, MD The authors have no financial interest in the subject matter of this poster

  2. Background • Accurate measurement of the dark-adapted pupil diameter (DAPD) has become a standard element of the pre-operative assessment for corneal and intraocular refractive surgery • Most pupillometers in clinical use occlude one eye, which theoretically enlarges pupil size by halving the total retinal light flux • No independent clinical data have been presented comparing a monocular device to a binocular free-viewing device

  3. Purpose To assess the performance of a binocular free-viewing autorefractor with pupillometry function against a monocular occlusion pupillometer (Neuroptics Pupillometer or NOP) of known clinical performance. Note: The NOP has been validated in previous studies to be reliable under our test conditions.1

  4. Devices Used WAM-5500 Binocular Accommodation Instrument (FVAR) NeurOptics pupillometer (NOP)

  5. Methods • All subjects were volunteers without strabismus, prior intraocular surgery, or trauma affecting pupillary shape • Device test order and eye test order were randomized • All subjects were dark-adapted prior to testing • 50 patients, divided evenly into groups by age, were tested under 1 lux and 7 lux ambient illumination with controlled distance fixation at 20 feet • Testing with the FVAR was done with both eyes open (binocular) and repeated with one eye occluded (monocular) • Testing with the NOP was repeated until a standard deviation <0.07 mm was obtained

  6. Results • FVAR had clinically unacceptable outliers of ≥ 0.5 mm in DAPD at both illumination levels tested • At all age decades, FVAR underestimates DAPD • Right or left eye testing order and which device was tested first did not affect results

  7. Results • The FVAR is quite sensitive to small degrees of parallax and decentration and significant effort was required to obtain measurements even in fully cooperative subjects. • The FVAR takes only one measurement of pupil size instead of averaging several measurements and providing a standard deviation (SD) • Pupil size is larger when occluding one eye when testing with the FVAR

  8. Results Mean DAPD (in mm) as a function of age for the NOP & FVAR at 1 & 7 lux

  9. Results Difference in DAPD (in mm) between NOP & Binocular FVAR

  10. Results Difference (in mm) between right eye DAPD with left eye occluded and with both eyes open using FVAR

  11. Conclusions • The WAM 5500 pupillometry function frequently disagreed with the NOP by ≥ 0.5 mm in DAPD. • Testing the first eye with the NOP does not induce sustained pupillary constriction that biases the result of the second eye. • The FVAR is technically more difficult to operate than the NOP • FVAR accuracy may suffer since the device obtains only a single measurement instead of averaging several • FVAR measurements suggest pupil size is larger with one eye occluded

  12. References 1. Bradley JC, Bentley KC, Mughal AI, Brown SM. Clinical performance of a handheld digital infrared monocular pupillometer for measurement of the dark-adapted pupil diameter. J Cataract Refract Surg 2010;36:277-81. 2. Boxer Wachler BS. Effect of pupil size on visual function under monocular and binocular conditions in LASIK and non-LASIK patients. J Cataract Refract Surg 2003;29:275-8. 3. Kurz S, Krummenauer F, Pfeiffer N, Dick HB. Monocular versus binocular pupillometry. J Cataract Refract Surg 2004;30:2551-6. 4. Scheffel M, Kuehne C, Kohnen T. Comparison of monocular and binocular infrared pupillometers under mesopic lighting conditions. J Cataract Refract Surg 2010;36:625-30. 5. Brown SM. Monocular versus binocular pupillometry. J Cataract Refract Surg 2006;32:374-5. 6. Ettinger ER, Wyatt HJ, London R. Anisocoria. Variation and clinical observation with different conditions of illumination and accommodation. Invest Ophthalmol Vis Sci 1991;32:501-9. 7. Lam BL, Thompson HS, Corbett JJ. The prevalence of simple anisocoria. Am J Ophthalmol 1987;104:69-73.

More Related