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Updated: Jan 29, 2026

Pupillary Response as Assessment of Effective Seizure Induction by Electroconvulsive Therapy
Published on: April 11, 2019
A 30 s test for quantitative assessment of a relative afferent pupillary defect (RAPD): the infrared pupillary
Nathalie Stéphanie Meneguette1,2, J Emanuel Ramos de Carvalho2,3, Axel Petzold4,5,6
1Department of Neurology and Ophthalmology, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil.
Background:
Detection of a relative afferent pupillary defect (RAPD) by the swinging-light test can be challenging in clinical practice (dark eyes, anisocoria, dark environment). We developed a new method of RAPD quantification based on the recording of the infrared pupillary asymmetry (IPA) with a standard optical coherence tomography (OCT) device.
Methods:
The diagnostic value of the IPA for detection of the RAPD was determined by receiver-operating characteristic (ROC) curves and area under the curve (AUC).
Results:
Twenty-nine subjects were included in this study (17 controls and 12 unilateral optic neuropathies). The IPA was significantly greater in unilateral optic neuropathies (0.39) compared to controls (0.18, p = 0.001). The diagnostic value was good with a ROC-AUC of 0.843. Importantly, the IPA correlated significantly with the inter-eye percentage difference of the macular ganglion cell-inner plexiform layer (mGCIPL) thickness (R = 0.53, p = 0.01). Assessment of the IPA took less than 30 s.
Conclusion:
The present data show that the IPA is a practical and rapid test that can be applied in a clinical setting. The IPA may be a valuable functional outcome measure for clinical trials, complementing structural retinal OCT data in a biological meaningful way. The IPA should be further investigated for suitability for optic neuritis treatment trials.
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