Environmental Localization Mapping and Guidance for Visual Prosthesis Users

Retinitis Pigmentosa Clinical Trial

— SLAM  

Official title:

Environmental Localization Mapping and Guidance for Visual Prosthesis Users

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT04359108
• Other study ID #: IRB00228932
• Secondary ID: 1R01EY029741-01A
• Status: Recruiting
• Phase: N/A
• Start date: March 16, 2021
• Est. completion date: July 30, 2024

Study information

• Verified date: June 2024
• Source: Johns Hopkins University
• Contact: Seth Billings, Ph.D.
• Phone: 4437787462
• Email: seth.billings[@]jhuapl.edu
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study is driven by the hypothesis that navigation for users of retinal prosthetics can be greatly improved by incorporating Spatial Localization and Mapping (SLAM) and object recognition technology conveying environmental information via a retinal prosthesis and auditory feedback. The investigators will study how effectively the SLAM technology enables the visual prosthesis system to construct a map of the user's environment and locate the user within that map. The technology will be tested both with normally sighted individuals donning a virtual reality headset and with retinal prosthesis users (Argus II).

Description:

About 1.3 million Americans aged 40 and older are legally blind, a majority because of diseases with onset later in life, such as glaucoma and age-related macular degeneration. Second Sight Medical Products (SSMP) has developed the world's first FDA approved retinal implant, Argus II, intended to restore some functional vision for people suffering from retinitis pigmentosa (RP). In this era of smart devices, generic navigation technology, such as GPS mapping apps for smartphones, can provide directions to help guide a blind user from point A to point B. However, these navigational aids do little to enable blind users to form an egocentric understanding of the surroundings, are not suited to navigation indoors, and do nothing to assist in avoiding obstacles to mobility. The Argus II, on the other hand, provides blind users with a limited visual representation of their surroundings that improves users' ability to orient themselves and traverse obstacles, yet lacks features for high-level navigation and semantic interpretation of the surroundings. The proposed study aims to address these limitations of the Argus II through a synergy of state-of-the-art simultaneous localization and mapping (SLAM) and object recognition technologies.

This study is driven by the hypothesis that navigation for users of retinal prosthetics can be greatly improved by incorporating SLAM and object recognition technology conveying environmental information via a retinal prosthesis and auditory feedback. SLAM enables the visual prosthesis system to construct a map of the user's environment and locate the user within that map. The system then provides object location and navigational cues via appropriate sensory modalities enabling the user to mentally form an egocentric map of the environment. Investigators will develop and test a visual prosthesis system which 1) constructs a map of unfamiliar environments and localizes the user using SLAM technology 2) automatically identifies navigationally-relevant objects and landmarks using object recognition and 3) provides sensory feedback for navigation, obstacle avoidance, and object/landmark identification.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 35
• Est. completion date: July 30, 2024
• Est. primary completion date: July 30, 2024
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Criteria for inclusion of normally sighted individuals:

• Subject speaks English;

• Subjects must be an adult (at least 18 years of age);

• Subject has the cognitive and communication ability to participate in the study (i.e., follow spoken directions, perform tests, and give feedback);

• Subject is willing to conduct psychophysics testing up to 4-6 hours per day of testing on 3-5 consecutive days;

• Subject has visual acuity of 20/40 or better (corrected);

• Subject is capable of understanding participant information materials and giving written informed consent.

• Subject is able to walk unassisted

Criteria for inclusion of Argus II users:

The inclusion criteria for the study are the following:

• Subject is at least 25 years of age;

• Subject has been implanted with the Argus II system;

• Subject's eye has healed from surgery and the surgeon has cleared the subject for programming;

• Subject has the cognitive and communication ability to participate in the study (i.e., follow spoken directions, perform tests, and give feedback);

• Subject is willing to conduct psychophysics testing up to 4-6 hours per day of testing on 3-5 consecutive days;

• Subject is capable of understanding patient information materials and giving written informed consent;

• Subject is able to walk unassisted.

Exclusion criteria for all subjects is the following:

• Subject is unwilling or unable to travel to testing facility for at least 3 days of testing within a one-week timeframe;

• Subject does not speak English;

• Subject has language or hearing impairment.

Related Conditions & MeSH terms

• Retinitis
• Retinitis Pigmentosa
• Vision Disorders
• Vision, Low
• Visual Impairment
• Visual Prosthesis

Intervention

Device:
• Navigation System for Users of a Visual Prosthesis
We use common psychophysical judgments such as the following: discriminating between two alternatives by saying which is present in the field of view, touching a tablet computer to indicate the apparent location of a target in the frontal plane, and looking for targets by rotating the head and pointing when one is found. We will compare user performance using the Basic system with user performance using the Augmented and Augmented + Modal systems where contextual information associated with the task is conveyed to users via enhanced visual, auditory, and haptic modalities.

Locations

Country	Name	City	State
United States	Johns Hopkins Medicine - Wilmer Eye Institute	Baltimore	Maryland
United States	Johns Hopkins Applied Physics Laboratory	Laurel	Maryland

Sponsors (3)

Lead Sponsor	Collaborator
Johns Hopkins University	Carnegie Mellon University, National Eye Institute (NEI)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Accuracy as assessed as ratio of target identification success to total trials	The participant will be asked to identify intended targets in a closed environment, as well as to navigate to intended targets. We will measure accuracy as the total number of successes divided by the total number of trials.	Up to 5 minutes
Primary	Trial Time as assessed by mean time duration to identify target	This will be assessed by the mean duration of time to identify intended target (in seconds). For successful trials, the shorter the amount of time to conduct a task, the better the performance on said task.	Up to 5 minutes
Primary	Success in psychophysical judgments	This will be assessed by the metric error in distance judgment, that is, the correctness of identification of judgments of target features. Measurement in meters.	Trial Duration: estimated at up to one minute.