An interventional study of Collision warning device in Hemianopia, Hemianopsia and Peripheral Visual Field Defect, sponsored by Massachusetts Eye and Ear Infirmary. Completed at 1 site in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2021-02-10.
Sponsored by Massachusetts Eye and Ear Infirmary · Not applicable, Interventional, and Other
This study evaluates a novel collision warning device to help people with severe vision impairment or blindness avoid collisions with obstacles. The main hypothesis to be tested is that the device reduces the number of collisions with obstacles in everyday activities.
Participants with blindness or severe visual field loss (hemianopia or tunnel vision) will be trained to use a collision warning device that alerts them to impending collisions. Participants will use the device at home during everyday mobility for about 1 month. The device is designed to supplement existing mobility devices, such as a long cane or dog guide. The device will provide warnings about potential collisions with mid- or high-level obstacles (which are typically not detected by a long cane).
63 studies on the registry are indexed under Hemianopsia; 24 are open to participants now.
This study's enrollment of 49 is above the median of 32 across 53 interventional studies indexed under Hemianopsia.
Browse Hemianopsia studies →Massachusetts Eye and Ear Infirmary is the lead sponsor of 100 studies on the registry; 23 are open to participants now.
Of its 13 completed or terminated interventional studies of FDA-regulated products, 7 (54%) have results posted.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Participants will use the collision warning device as much as possible for about one month during everyday activities, when walking indoors and outdoors.
Device: Collision warning device
The collision warning device is a pocket-sized, electronic system that includes a micro-computer, a clip-on miniature camera, a gyro-sensor, an accelerometer, and a rechargeable battery, all contained within a shoulder bag. It is about the size of a smart phone. When a potential collision is detected by the device it emits a warning to the user, either in the form of an audible beep or a tactile warning through bracelets worn on the wrist. The time to collision will be coded in both the auditory and tactile domains. The device is designed to only give warnings about high risk collisions, so the users will not be continually bombarded by warnings for every potential collision object in the environment.
Number of Collision Incidents (All Contacts)
Collision incidents recorded by the device in everyday use, including long cane contacts and body contacts with surrounding objects in the environment.
Time frame: During the one-month period of device use
Number of Body Contacts
Collision incidents with body contacts recorded by the device
Time frame: During the one-month period of device use
Device Questionnaire
Questionnaire addressing participants' experiences of using the device. Scores were on a 5-point rating scale (1 to 5) with higher scores representing a better score. Questions were grouped into four main categories: i) overall satisfaction, ii) comfort, iii) mobility benefit, and iv) ease of operation. An average score was computed for questions within each category.
Time frame: During the one-month period of device use
Subjects were recruited between January 2018 and May 2019 via referrals from the Carroll Center for the Blind, the Massachusetts Commission for the Blind and practitioners at vision rehabilitation clinics in the Greater Boston area, and via a pool of volunteers who had previously participated in studies in our lab.
| Milestone | Silent and Active Mode |
|---|---|
| Started | 49 |
| Started home-use trial | 36 |
| Completed | 31 |
| Not completed | 18 |
| Withdrew: Withdrawal by subject | 8 |
| Withdrew: Lost to follow-up | 5 |
| Withdrew: Did not use device during home trial | 3 |
| Withdrew: Device failure | 2 |
Collision incidents recorded by the device in everyday use, including long cane contacts and body contacts with surrounding objects in the environment.
| Rate (contacts per 100 hazards per hour) | Silent Mode | Active Mode |
|---|---|---|
| Number of Collision Incidents (All Contacts) | 13.79 (7.28 to 24.29) | 9.26 (6.56 to 14.96) |
Collision incidents with body contacts recorded by the device
| Rate (contacts per 100 hazards per hour) | Silent Mode | Active Mode |
|---|---|---|
| Number of Body Contacts | 1.13 (0.45 to 3.08) | 1.09 (0.3 to 1.97) |
Questionnaire addressing participants' experiences of using the device. Scores were on a 5-point rating scale (1 to 5) with higher scores representing a better score. Questions were grouped into four main categories: i) overall satisfaction, ii) comfort, iii) mobility benefit, and iv) ease of operation. An average score was computed for questions within each category.
| scores on a scale | Silent and Active Mode |
|---|---|
| Overall satisfaction | 3.68 ± 0.74 |
| Comfort | 4.08 ± 0.53 |
| Mobility benefit | 3.05 ± 1.08 |
| Ease of operation | 3.96 ± 0.49 |
Collected over Adverse event data were collected during the one-month period when subjects were using the device.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Silent and Active Mode | 0/36 (0%) | 0/36 (0%) | 6/36 (16.7%) |
| Event | Silent and Active Mode |
|---|---|
| Minor contact with object in the environmentGeneral disorders | 6/36 |
The baseline analysis population includes only those subjects who completed the one-month period of device use and had data successfully recorded by the device.
| Age, Continuous(Years) | Silent and Active Mode |
|---|---|
| Median | 61 (25 to 73) |
| Sex: Female, Male(Participants) | Silent and Active Mode |
|---|---|
| Female | 13 |
| Male | 18 |
| Ethnicity (NIH/OMB)(Participants) | Silent and Active Mode |
|---|---|
| Hispanic or Latino | 0 |
| Not Hispanic or Latino | 28 |
| Unknown or Not Reported | 3 |
| Race (NIH/OMB)(Participants) | Silent and Active Mode |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 1 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 8 |
| White | 18 |
| More than one race | 1 |
| Unknown or Not Reported | 3 |
| Region of Enrollment(participants) | Silent and Active Mode |
|---|---|
| United States | 31 |
| Habitual mobility aid(Participants) | Silent and Active Mode |
|---|---|
| Long cane | 28 |
| Guide dog | 3 |
| Cause of vision impairment(Participants) | Silent and Active Mode |
|---|---|
| Retinitis Pigmentosa | 8 |
| Retinopathy of prematurity | 5 |
| Other | 15 |
| Unknown | 3 |
| Vision impairment onset(Participants) | Silent and Active Mode |
|---|---|
| At birth | 17 |
| Adult | 14 |
2 further baseline measures are reported on the registry.
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
Ran from Jan 2018 to primary completion in Nov 2019, 21 months.
Results were first posted in Dec 2020, 1 year 1 month after primary completion.
Of 36 interventional studies with no phase under Hemianopsia, half reached primary completion within 47 months of starting (the median), counting those still running; a quarter within 21 and three quarters within 95. This study's 21 months is below that.
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This study is completed, as verified in Jan 2021. You cannot join it, but the record below documents what was studied.
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