Dataset Information

Oculomotor Responses to Dynamic Stimuli in a 44-Channel Suprachoroidal Retinal Prosthesis.

ABSTRACT:

Purpose

To investigate oculomotor behavior in response to dynamic stimuli in retinal implant recipients.

Methods

Three suprachoroidal retinal implant recipients performed a four-alternative forced-choice motion discrimination task over six sessions longitudinally. Stimuli were a single white bar ("moving bar") or a series of white bars ("moving grating") sweeping left, right, up, or down across a 42? monitor. Performance was compared with normal video processing and scrambled video processing (randomized image-to-electrode mapping to disrupt spatiotemporal structure). Eye and head movement was monitored throughout the task.

Results

Two subjects had diminished performance with scrambling, suggesting retinotopic discrimination was used in the normal condition and made smooth pursuit eye movements congruent to the moving bar stimulus direction. These two subjects also made stimulus-related eye movements resembling optokinetic reflex (OKR) for moving grating stimuli, but the movement was incongruent with stimulus direction. The third subject was less adept at the task, appeared primarily reliant on head position cues (head movements were congruent to stimulus direction), and did not exhibit retinotopic discrimination and associated eye movements.

Conclusions

Our observation of smooth pursuit indicates residual functionality of cortical direction-selective circuits and implies a more naturalistic perception of motion than expected. A distorted OKR implies improper functionality of retinal direction-selective circuits, possibly due to retinal remodeling or the non-selective nature of the electrical stimulation.

Translational relevance

Retinal implant users can make naturalistic eye movements in response to moving stimuli, highlighting the potential for eye tracker feedback to improve perceptual localization and image stabilization in camera-based visual prostheses.

SUBMITTER: Titchener SA

PROVIDER: S-EPMC7757638 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Publications

Oculomotor Responses to Dynamic Stimuli in a 44-Channel Suprachoroidal Retinal Prosthesis.

Titchener Samuel A SA Kvansakul Jessica J Shivdasani Mohit N MN Fallon James B JB Nayagam D A X DAX Epp Stephanie B SB Williams Chris E CE Barnes Nick N Kentler William G WG Kolic Maria M Baglin Elizabeth K EK Ayton Lauren N LN Abbott Carla J CJ Luu Chi D CD Allen Penelope J PJ Petoe Matthew A MA

Translational vision science & technology 20201218 13

<h4>Purpose</h4>To investigate oculomotor behavior in response to dynamic stimuli in retinal implant recipients.<h4>Methods</h4>Three suprachoroidal retinal implant recipients performed a four-alternative forced-choice motion discrimination task over six sessions longitudinally. Stimuli were a single white bar ("moving bar") or a series of white bars ("moving grating") sweeping left, right, up, or down across a 42″ monitor. Performance was compared with normal video processing and scrambled vide ...[more]

PMID: 33384885

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Project description:ImportanceIn-office suprachoroidal viscopexy (SCVEXY) is a minimally invasive technique for rhegmatogenous retinal detachment (RRD) repair that can be performed with no incision, no tamponade agent, and no positioning requirements. This technique has the potential to be a step forward in the armamentarium to treat RRDs.ObjectiveTo describe in-office SCVEXY for RRD repair.Design, setting, and participantIn this single-case report with short follow-up, a man in his 50s with pseudophakia and recent visual loss presented to St Michael's Hospital, Unity Health Toronto, with a fovea-off RRD in the right eye, extending from 6 to 10 o'clock, with no visible causative retinal break.ExposureInjection of suprachoroidal sodium hyaluronate, 1%, in the region of the suspected break, using a 30-gauge needle with a custom-made guard that exposed only 1 mm of the needle.Main outcome and measuresAbility to perform in-office SCVEXY and to obtain a visible choroidal indentation.ResultsAfter the procedure, a dome-shaped choroidal convexity was present in the superior temporal area. The patient achieved macular reattachment in less than 24 hours with no postoperative abnormalities, such as outer retinal folds, residual subfoveal fluid, or retinal displacement, with rapid recovery of the outer retinal bands on optical coherence tomography. The optical coherence tomography scans acquired in the area of the choroidal convexity demonstrated the location of the viscoelastic material in the suprachoroidal space. Laser retinopexy was applied in the suspected region of the retinal tear, and the patient was able to resume normal activity immediately after the procedure with no restrictions.Conclusions and relevanceSuprachoroidal viscopexy is feasible as an in-office technique to create a temporary choroidal buckle for RRD repair. It is a minimally invasive procedure with the potential to maximize anatomical outcomes of integrity and postoperative functional outcomes in RRD because its mechanism of action does not require drainage of subretinal fluid or intraocular gas tamponade. Nevertheless, this was a single-case report with short follow-up, which limits the ability to determine the procedure's benefits, potential adverse events, failure rates, and best-case selection. Further work is required to refine the procedure and assess its efficacy and safety.

Dataset Information

Oculomotor Responses to Dynamic Stimuli in a 44-Channel Suprachoroidal Retinal Prosthesis.

Purpose

Methods

Results

Conclusions

Translational relevance

Publications

Oculomotor Responses to Dynamic Stimuli in a 44-Channel Suprachoroidal Retinal Prosthesis.

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