Theranostics 2022; 12(7):3273-3287. doi:10.7150/thno.71164 This issue

Research Paper

Optic chiasmatic potential by endoscopically implanted skull base microinvasive biosensor: a brain-machine interface approach for anterior visual pathway assessment

Yikui Zhang1✉*, Shengjian Lu1*, Shenghai Huang1, Zhonghao Yu1, Tian Xia1, Mengyun Li1, Chen Yang1, Yiyang Mao1, Boyue Xu1, Lixu Wang1, Lei Xu2, Jieliang Shi1, Xingfang Zhu1, Senmiao Zhu1, Si Zhang1, Haohua Qian3, Yang Hu4✉, Wei Li5✉, Yunhai Tu1✉, Wencan Wu1✉

1. The Eye Hospital, School of Ophthalmology & Optometry, Wenzhou Medical University; Wenzhou 325027, China.
2. Medical Radiology Department, 2nd Affiliated Hospital, Wenzhou Medical University; Wenzhou 325027, China.
3. Visual Function Core, National Eye Institute, National Institute of Health, NIH; Bethesda, United States.
4. Department of Ophthalmology, Stanford University School of Medicine; Palo Alto, United States.
5. Retinal Neurophysiology Section, National Eye Institute, National Institute of Health, NIH; Bethesda, United States.
*These authors contributed equally to this work.

This is an open access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/). See http://ivyspring.com/terms for full terms and conditions.
Citation:
Zhang Y, Lu S, Huang S, Yu Z, Xia T, Li M, Yang C, Mao Y, Xu B, Wang L, Xu L, Shi J, Zhu X, Zhu S, Zhang S, Qian H, Hu Y, Li W, Tu Y, Wu W. Optic chiasmatic potential by endoscopically implanted skull base microinvasive biosensor: a brain-machine interface approach for anterior visual pathway assessment. Theranostics 2022; 12(7):3273-3287. doi:10.7150/thno.71164. Available from https://www.thno.org/v12p3273.htm

File import instruction

Abstract

Graphic abstract

Background: Visually evoked potential (VEP) is widely used to detect optic neuropathy in basic research and clinical practice. Traditionally, VEP is recorded non-invasively from the surface of the skull over the visual cortex. However, its trace amplitude is highly variable, largely due to intracranial modulation and artifacts. Therefore, a safe test with a strong and stable signal is highly desirable to assess optic nerve function, particularly in neurosurgical settings and animal experiments.

Methods: Minimally invasive trans-sphenoidal endoscopic recording of optic chiasmatic potential (OCP) was carried out with a titanium screw implanted onto the sphenoid bone beneath the optic chiasm in the goat, whose sphenoidal anatomy is more human-like than non-human primates.

Results: The implantation procedure was swift (within 30 min) and did not cause any detectable abnormality in fetching/moving behaviors, skull CT scans and ophthalmic tests after surgery. Compared with traditional VEP, the amplitude of OCP was 5-10 times stronger, more sensitive to weak light stimulus and its subtle changes, and was more repeatable, even under extremely low general anesthesia. Moreover, the OCP signal relied on ipsilateral light stimulation, and was abolished immediately after complete optic nerve (ON) transection. Through proof-of-concept experiments, we demonstrated several potential applications of the OCP device: (1) real-time detector of ON function, (2) detector of region-biased retinal sensitivity, and (3) therapeutic electrical stimulator for the optic nerve with low and thus safe excitation threshold.

Conclusions: OCP developed in this study will be valuable for both vision research and clinical practice. This study also provides a safe endoscopic approach to implant skull base brain-machine interface, and a feasible in vivo testbed (goat) for evaluating safety and efficacy of skull base brain-machine interface.

Keywords: Microinvasive biosensor, trans-nasal endoscopy, skull base brain-machine interface, visual evoked potential, optic chiasmatic potential