Development of a Cortical Visual Neuroprosthesis for the Blind

NCT02983370 | Recruiting

• 1 other identifier: CORTIVIS16-HUM1
• Study Type: interventional
• Target: 5
• Locations: 1 country
• Sites: 2

Brief Summary

The objective of this study is to evaluate the usefulness of a cortical visual prosthesis based on intracortical microelectrodes to provide a limited but useful sense of vision to profoundly blind. This pilot study will provide important information on safety and efficacy for the development of an useful cortical visual neuroprosthesis for the blind.

Conditions

Blindness

Outcome Measures

Primary Outcomes (1)

• Thresholds of visual perceptions elicited by intracortical microstimulation

  Charges needed for eliciting visual perceptions through electrical stimulation of the human cortex

  Within implantation period (up to 6 months)

Secondary Outcomes (5)

• Phosphene mapping

  Within implantation period (up to 6 months)

• Visual Acuity

  Within implantation period (up to 6 months)

• Motion perception

  Within implantation period (up to 6 months)

• Visual function

  Within implantation period (up to 6 months)

• Number of participants with significant adverse events.

  Within implantation period (up to 6 months)

Study Arms (1)

Blind volunteer

EXPERIMENTAL

Blind volunteers will be implanted with our existing vision neuroprosthetic system, which utilizes a FDA cleared microelectrode array, using a minicraniotomy. The array will be implanted near the occipital pole or in extra striate areas. The investigators will collect descriptive feedback regarding thresholds, evoked perceptions and stimulation parameters leading to recognizable patterns.

Procedure: Minicraniotomy

Interventions

Minicraniotomy PROCEDURE

The surgical method for the implantation of the intracortical microelectrodes is straightforward and follows the standard neurosurgical procedures. Briefly, after the scalp is prepped with an antiseptic, a small skin incision is made. Then the skin and muscles are lifted off from the bone and folded back. Next, one small burr hole or a minicraniotomy of approximately 1.5 cm is made in the skull. This is a minimally invasive procedure that allows an easy access to the brain and is a standard procedure widely used in neurosurgery.

Blind volunteer

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Participant is capable and willing to provide informed consent for participation in the trial.
• Severe visual impairment with bilateral visual loss.
• Greater than 18 years of age.
• General health: excellent.
• Following a general physical and neurological examination, patient must have normal serum electrolytes, C-reactive protein, complete blood count and PT and PTT.
• No history of stroke, seizure, coagulopathy, cardiac arrhythmias or ischemia, pulmonary, hepatic or renal disease, nor transmissible viruses such as hepatitis or HIV.
• Stable dose of current regular medication for at least four weeks prior to trial entry.
• Able to perform the study during the full time period of up to 6 months.
• Special consideration will be given to patients with (1) detailed medical histories, including documentation of the onset, mechanism and evolution of the blindness; (2) lower risks associated with surgery; and (3) no psychiatric disorders or other mental disabilities.

You may not qualify if:

• Age \<18 or \>70.
• Period of appropriate visual functions \< 12 years /lifetime.
• For medical reasons: Individuals with a history of seizure disorders, coagulopathy, cardiac arrythmias or ischemia, pulmonary, hepatic or renal disease, and any other neurological disorder. Patients who carry a transmissible virus such as hepatitis and individuals with HIV-related neuropathies.
• Vulnerable subject groups (e.g., pregnant women, prisoners, etc.).
• Persons unable to give written informed consent prior to participation in the study.
• Not able to perform the study during the full time period (at least 3 months).
• Any other significant disease or disorder which, in the opinion of the Investigator, may either put the participants at risk because of participation in the trial, or may influence the result of the trial, or the participant's ability to participate in the trial.

Sponsors & Collaborators

• Universidad Miguel Hernandez de Elche: lead
• Hospital IMED Elche: collaborator

Study Sites (2)

Hospital IMED Elche

Elche, Alicante, 03202, Spain

RECRUITING

Universidad Miguel Hernandez de Elche

Elche, Alicante, 03202, Spain

RECRUITING

Related Publications (24)

• Martinez-Alvarez A, Crespo-Cano R, Diaz-Tahoces A, Cuenca-Asensi S, Ferrandez Vicente JM, Fernandez E. Automatic Tuning of a Retina Model for a Cortical Visual Neuroprosthesis Using a Multi-Objective Optimization Genetic Algorithm. Int J Neural Syst. 2016 Nov;26(7):1650021. doi: 10.1142/S0129065716500210. Epub 2016 Mar 29.

  PMID: 27354187 BACKGROUND

• Alfaro A, Bernabeu A, Agullo C, Parra J, Fernandez E. Hearing colors: an example of brain plasticity. Front Syst Neurosci. 2015 Apr 14;9:56. doi: 10.3389/fnsys.2015.00056. eCollection 2015.

  PMID: 25926778 BACKGROUND

• Fernandez E, Greger B, House PA, Aranda I, Botella C, Albisua J, Soto-Sanchez C, Alfaro A, Normann RA. Acute human brain responses to intracortical microelectrode arrays: challenges and future prospects. Front Neuroeng. 2014 Jul 21;7:24. doi: 10.3389/fneng.2014.00024. eCollection 2014.

  PMID: 25100989 BACKGROUND

• Normann RA, Greger B, House P, Romero SF, Pelayo F, Fernandez E. Toward the development of a cortically based visual neuroprosthesis. J Neural Eng. 2009 Jun;6(3):035001. doi: 10.1088/1741-2560/6/3/035001. Epub 2009 May 20.

  PMID: 19458403 BACKGROUND

• Warren DJ, Fernandez E, Normann RA. High-resolution two-dimensional spatial mapping of cat striate cortex using a 100-microelectrode array. Neuroscience. 2001;105(1):19-31. doi: 10.1016/s0306-4522(01)00174-9.

  PMID: 11483297 BACKGROUND

• Maynard EM, Fernandez E, Normann RA. A technique to prevent dural adhesions to chronically implanted microelectrode arrays. J Neurosci Methods. 2000 Apr 15;97(2):93-101. doi: 10.1016/s0165-0270(00)00159-x.

  PMID: 10788663 BACKGROUND

• Morillas CA, Romero SF, Martinez A, Pelayo FJ, Ros E, Fernandez E. A design framework to model retinas. Biosystems. 2007 Feb;87(2-3):156-63. doi: 10.1016/j.biosystems.2006.09.009. Epub 2006 Sep 7.

  PMID: 17011701 BACKGROUND

• Fernandez E, Pelayo F, Romero S, Bongard M, Marin C, Alfaro A, Merabet L. Development of a cortical visual neuroprosthesis for the blind: the relevance of neuroplasticity. J Neural Eng. 2005 Dec;2(4):R1-12. doi: 10.1088/1741-2560/2/4/R01. Epub 2005 Nov 29.

  PMID: 16317227 BACKGROUND

• Marin C, Fernandez E. Biocompatibility of intracortical microelectrodes: current status and future prospects. Front Neuroeng. 2010 May 28;3:8. doi: 10.3389/fneng.2010.00008. eCollection 2010.

  PMID: 20577634 BACKGROUND

• Bernabeu A, Alfaro A, Garcia M, Fernandez E. Proton magnetic resonance spectroscopy (1H-MRS) reveals the presence of elevated myo-inositol in the occipital cortex of blind subjects. Neuroimage. 2009 Oct 1;47(4):1172-6. doi: 10.1016/j.neuroimage.2009.04.080. Epub 2009 May 5.

  PMID: 19426816 BACKGROUND

• Normann RA, Fernandez E. Clinical applications of penetrating neural interfaces and Utah Electrode Array technologies. J Neural Eng. 2016 Dec;13(6):061003. doi: 10.1088/1741-2560/13/6/061003. Epub 2016 Oct 20.

  PMID: 27762237 BACKGROUND

• Fernandez E, Alfaro A, Soto-Sanchez C, Gonzalez-Lopez P, Lozano AM, Pena S, Grima MD, Rodil A, Gomez B, Chen X, Roelfsema PR, Rolston JD, Davis TS, Normann RA. Visual percepts evoked with an intracortical 96-channel microelectrode array inserted in human occipital cortex. J Clin Invest. 2021 Dec 1;131(23):e151331. doi: 10.1172/JCI151331.

  PMID: 34665780 BACKGROUND

• Kucukoglu B, Soo L, Leeftink D, Grani F, Soto Sanchez C, Guclu U, van Gerven M, Fernandez E. Bayesian optimization of cortical neuroprosthetic vision using perceptual feedback. J Neural Eng. 2025 Jul 24;22(4). doi: 10.1088/1741-2552/adeae9.

  PMID: 40602416 RESULT

• Alfaro A, Soo L, Waclawczyk D, Morollon R, Grani F, Fernandez E. The unexpected sight: improvement of visual function following intracortical microstimulation of the human occipital cortex. Brain Commun. 2026 Feb 3;8(1):fcaf504. doi: 10.1093/braincomms/fcaf504. eCollection 2026.

  PMID: 41788163 RESULT

• Lozano A, Chen X, La Grouw M, Li B, Wang F, van der Grinten M, Soto-Sanchez C, Morales-Gregorio A, Fernandez E, Roelfsema PR. Large-scale mapping of artificial perceptions for neuroprostheses using spontaneous neuronal activity in macaque and human visual cortex. Brain Stimul. 2026 Jan-Feb;19(1):103019. doi: 10.1016/j.brs.2025.103019. Epub 2025 Dec 29.

  PMID: 41475513 RESULT

• Grani F, Soto-Sanchez C, Rodil Doblado A, Lopez Peco R, Gonzalez-Lopez P, Fernandez E. Neural correlates of phosphene perception in blind individuals: A step toward a bidirectional cortical visual prosthesis. Sci Adv. 2025 Nov 7;11(45):eadv8846. doi: 10.1126/sciadv.adv8846. Epub 2025 Nov 5.

  PMID: 41191758 RESULT

• Ruiz RM, Garces JAC, Soo L, Fernandez E. Enhancing Orientation and Mobility Assessments: Integrating Visual and Auditory Factors Using Artificial Intelligence Tools. Transl Vis Sci Technol. 2025 Jul 1;14(7):14. doi: 10.1167/tvst.14.7.14.

  PMID: 40689721 RESULT

• Waclawczyk D, Soo L, Morollon Ruiz R, Caspi A, Fernandez E. Integrating Eye-Tracking With Cortical Visual Prostheses in Patients Without Eyes: A Case Study. IEEE Trans Neural Syst Rehabil Eng. 2025;33:3998-4007. doi: 10.1109/TNSRE.2025.3615286.

  PMID: 41021945 RESULT

• Lopez-Peco R, Val-Calvo M, Soto-Sanchez C, Villamarin-Ortiz A, Ruiz-Boix G, Ferrandez-Vicente JM, Fernandez E. Neuronal Waveform Classification in Multielectrode Recordings Using Machine Learning Techniques and Multidimensional Analysis. Int J Neural Syst. 2025 Jun;35(6):2550031. doi: 10.1142/S0129065725500315.

  PMID: 40375639 RESULT

• Farfan FD, Soo L, Grani F, Grima-Murcia MD, Fernandez E. Brain connectivity changes in response to cortical electrical stimulation in blind neuroprosthesis users. Cereb Cortex. 2025 Apr 1;35(4):bhaf075. doi: 10.1093/cercor/bhaf075.

  PMID: 40173310 RESULT

• Fernandez E, Robles JA. Advances and challenges in the development of visual prostheses. PLoS Biol. 2024 Oct 24;22(10):e3002896. doi: 10.1371/journal.pbio.3002896. eCollection 2024 Oct.

  PMID: 39446886 RESULT

• Rocca A, Lehner C, Wafula-Wekesa E, Luna E, Fernandez-Cornejo V, Abarca-Olivas J, Soto-Sanchez C, Fernandez-Jover E, Gonzalez-Lopez P. Robot-assisted implantation of a microelectrode array in the occipital lobe as a visual prosthesis: technical note. J Neurosurg. 2023 Oct 27;140(4):1169-1176. doi: 10.3171/2023.8.JNS23772. Print 2024 Apr 1.

  PMID: 37890180 RESULT

• Grani F, Soto-Sanchez C, Fimia A, Fernandez E. Toward a personalized closed-loop stimulation of the visual cortex: Advances and challenges. Front Cell Neurosci. 2022 Dec 13;16:1034270. doi: 10.3389/fncel.2022.1034270. eCollection 2022.

  PMID: 36582211 RESULT

• Grani F, Soto-Sanchez C, Farfan FD, Alfaro A, Grima MD, Rodil Doblado A, Fernandez E. Time stability and connectivity analysis with an intracortical 96-channel microelectrode array inserted in human visual cortex. J Neural Eng. 2022 Jul 22;19(4). doi: 10.1088/1741-2552/ac801d.

  PMID: 35817011 RESULT

MeSH Terms

Conditions

Blindness

Condition Hierarchy (Ancestors)

Vision Disorders; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Eye Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Eduardo Fernandez, MD and PhD

  Universidad Miguel Hernandez de Elche

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Eduardo Fernandez, MD and PhD

CONTACT

+34 965222001; e.fernandez@umh.es

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: OTHER
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD and PhD

Study Record Dates

• First Submitted: September 12, 2016
• First Posted: December 6, 2016
• Study Start: October 1, 2019
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): October 1, 2028
• Last Updated: May 5, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

ES (2)