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Preliminary data on a novel smart glasses system for measuring the angle of deviation in strabismus



To propose a novel smart glasses device for recording eye movement and compare its results to the prism alternate cover test (PACT).


This method comparison study enrolled patients with strabismic conditions, who first underwent conventional strabismus evaluations (PACT in the primary position), followed by the smart glasses NeuroSpeed system (NSS) recording protocols. The video recordings were analysed using specialized software, to calculate the horizontal deviation from the primary position. The results were compared with those of the PACT using Passing‒Bablok regression and Bland‒Altman analysis.


This study included 70 individuals aged 4 to 80 years, of which 38 were men and 32 were women. The overall analysis of horizontal deviations using the Passing‒Bablok regression revealed a correlation coefficient (r) of 0.969, with a systemic bias of 0.00, a proportional bias of 0.809, and a perpendicular residual standard deviation of 4.134.


The predictive values of eye movement examinations recorded by the NSS were comparable to those of the PACT. Thus, this new system can provide additional information for ophthalmologists to aid in the diagnosis and measurement of strabismus.

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Fig. 1: The NeuroSpeed system (NSS) recording protocol.
Fig. 2: Method comparison study between the prism alternate cover test (PACT) and the NeuroSpeed system (NSS)-based results.

Data availability

The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.


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We wish to thank the research team of Neurobit Technologies Co., Ltd (Chun-Chen Yang, Wei-Cheng Chen, Chin-Hsun Huang, and Ching-Fu Wang) for the development of the NeuroSpeed system (Ophthalmic version).


This research was funded by the MOST (Ministry of Science and Technology) (MOST 110-2314-B-016-051 and MOST 111-2314-B-016-035), TSGH (Tri-Service General Hospital) (TSGH-D-109190 and TSGH-D-110111) and Ministry of National Defense Medical Affairs Bureau (MND-MAB-C-11105-111019 and MND-MAB-C14-112057).

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Authors and Affiliations



Design of the study (KC) and conduct of the study (KC); data collection (KF, LL), data analysis (PC, LL), and interpretation of the data (KF, LL, KC); and preparation (YC), review (KC), and approval of the manuscript (KC, YC).

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Correspondence to Ke-Hung Chien.

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Lee, LC., Feng, K.M., Chuang, PC. et al. Preliminary data on a novel smart glasses system for measuring the angle of deviation in strabismus. Eye (2023).

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