Randomized Controlled Multicenter Clinical Trial of Multi-Periscopic Prism Glasses for Homonymous Hemianopia
Phase: NA
Conditions: Homonymous Hemianopia
Sponsor: Massachusetts Eye and Ear Infirmary

 
 
 
 
 
 
Randomized Controlled Multicenter Clinical Trial 
of Multi-Periscopic Prism Glasses for Homonymous Hemianopia 
 
NCT04827147  
 
IRB protocol and analysis plan 
12 June 2025 
 

 
 
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Institutional Review Board 
Intervention/Interaction Detailed Protocol 
 
 
Principal Investigator: 
Dr. Eliezer Peli OD 
 
Project Title: 
Randomized Controlled Multicenter Clinical Trial of Multi-Periscopic 
Prism Glasses for Homonymous Hemianopia 
 
Version Name: 
v 4 
Version Date: 
12 June 2025 
 
 
 
1. Background and Significance 
 
Patients with homonymous hemianopia (HH), the loss of half the field of vision on the same side in both 
eyes, have difficulties navigating and avoiding obstacles (Yates et al., 2002; Chen et al., 2009; Bowers et 
al., 2014a). The consequent loss of mobility, increased risk of collision with other pedestrians, falls due 
to tripping obstacles (Freeman et al., 2007), and unsafe driving (Bowers, 2016) are detrimental to 
patients’ independence and quality of life (Papageorgiou et al., 2007; Chen et al., 2009; O'Neill et al., 
2011).  
Prisms designed to shift portions of a scene from the blind field to the residual seeing field are 
the simplest, lightest, and most cost-effective devices for field expansion for patients with HH. 
Commercially available Fresnel peripheral prism (FPP) glasses (Fig. 1) have a maximum power of 57∆, 
providing about 30° of field expansion. In multicenter and laboratory-based studies, this field expansion 
was found to be helpful for detecting obstacles on the blind side when walking (Giorgi et al. 2009, 
Bowers et al, 2008; Bowers et al., 2014) and improved detection of blind side hazards in a driving 
simulator (Houston et al., 2018). However, current prism devices for patients with HH still have some 
limitations (Apfelbaum et al., 2013; Jung et al., 2014; Peli et al., 2016b; Peli et al., 2017a). In particular, 
currently available FPP glasses do not provide sufficient field expansion to enable detection of 
pedestrians approaching from a bearing angle of 45°, determined to be the bearing angle with the 
highest collision risk when walking (Peli et al., 2016a). Since the maximum power of currently available 
Fresnel prisms is only 57∆ (≈30°), these prisms fall short of covering the highest risk (45°).  
 
 
Figure 1: Commercially available Fresnel peripheral prism glasses 
manufactured by Chadwick Optical, shown here in front of the left eye for 
a patient with left HH. The 57 ∆ Fresnel prism segments are embedded in 
the upper and lower parts of the spectacle lens with a prism-free area 
between. Patients look through the prism-free area while the prism 
segments provide expansion in peripheral vision.   
 
To address the need for higher power prismatic devices, we have developed a new type of 
prismatic field expansion device for patients with HH, the “multi-periscopic prism” (MPP). The MPP is a 
specially arranged cascade of half-penta prisms (commonly used in binoculars) that provide 45° image 

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Detailed Protocol 
 
 
 
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shift (Fig. 2a) and facilitate a wide (15°) eye scanning range (Peli et al., 2016c; Peli et al., 2018). The half-
penta prisms are assembled using 3D-printed modules (Fig. 2b) and then mounted in spectacle carrier 
lenses as peripheral prisms (Fig. 2c). Since the MPP uses double reflections, it is free of refractive image 
quality effects such as distortion (minification), image dimming, and contrast reduction due to the color 
dispersion which limits the image quality of conventional Fresnel prisms (Katz, 2004b; Katz, 2004a). The 
method of use of the MPP does not differ from that of the conventional FPPs currently prescribed for 
patients with HH by optometrists or ophthalmologists; the MPP only provides a clearer image, wider 
field expansion, and facilitate 3 times wider eye scanning than is possible with the FPP. (Peli et al., 2020) 
 
Figure 2. MPP for field expansion. (a) Optical design of MPP (cascading 5 units of 8 mm width half-penta prisms) 
for HH with base left. The different rays indicate visual field at 15° steps (0° to 45°) all together showing a 45° 
shift and permitting an additional 15° eye scanning into the blind side. (b) CAD design (left) and 3D-printed 
prototype (right) of MPP for HH with base left (c) A prototype of peripheral MPPs mounted for left HH (base-in). 
The MPPs are mounted in front of the carrier lens and thus incorporate the spectacle correction. 
 
In early feasibility tests, prototype MPPs provided 45° (100Δ) of lateral field expansion for 
patients with HH, measured using a conventional visual fields test, and improved detection of 
pedestrians at bearing angles of 25° and 40° on the blind side in our VR walking simulator. In contrast, 
30° (57∆) FPP glasses improved detection of blind side pedestrians at a bearing angle of 25°, but not 40°. 
Based on these promising preliminary data we are now proposing to conduct a multi-site clinical trial to 
evaluate the MPPs for patients with HH.  
 
2. Specific Aims and Objectives  
We will conduct a multi-center randomized crossover clinical trial to evaluate the efficacy of Multi-
Periscopic Prisms (MPP) compared to conventional Fresnel peripheral prisms (FPP) as a mobility device 
for patients with HH.  We will evaluate the ability of the prismatic devices to improve detection of 
moving hazards on the side of the field loss.  
 
We hypothesize that performance will be better with the MPPs than the FPPs as evidenced by higher 
detection rates in the pedestrian detection and collision judgment task in our virtual reality (VR) walking 
simulator. In particular, we predict that the MPP will enable detection of pedestrians at much higher 
bearing angles on the side of the field loss and thereby protect against the higher risk for such collisions.  
 
 
 

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Detailed Protocol 
 
 
 
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3. General Description of Study Design 
 
This is a masked, randomized controlled multi-center trial (with a crossover design) to evaluate the 
efficacy of the MPP in comparison to the current standard of Fresnel peripheral prisms (FPP).  
 
 
 
 
 
 
Informed consent 
Screening 
Randomize eligible 
subjects 
Sequence AB 
Sequence BA 
Use MPP (4 weeks) 
Evaluation with MPP 
Use FPP (4 weeks) 
Evaluation with FPP 
Use FPP (4 weeks) 
Evaluation with FPP 
Use MPP (4 weeks) 
Evaluation with MPP 
Clinical decision  
Do not continue 
with glasses 
Continue with glasses 
for 12 months 
6 and 12 month 
telephone follow up 
Study ends 
Study ends 

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4. Subject Selection 
 
Inclusion/Exclusion criteria: 
• 
Inclusion Criteria: 
o At least 7 years of age 
o Homonymous hemianopia with or without macular sparing for at least 3 months 
o Visual acuity of at least 20/50 in each eye, with correction if needed 
o Refractive error within the -12D to +5D range 
o Able to walk independently, using a cane or walker if needed  
o Able to communicate in English sufficiently to understand the study procedures and 
how to use the prisms, to be determined by examiner’s judgement on visit 1 (because 
funding is not available for interpreter services) 
 
• 
Exclusion Criteria: 
o Central visual field loss in the seeing hemifield of either eye (e.g., from macular 
degeneration, glaucoma, diabetic retinopathy or other maculopathies) 
o Hemi-spatial neglect 
o Significant cognitive impairment 
o Dementia 
o Any other physical or mental disabilities, or general health problems that could impair 
the ability to be independently mobile (i.e., walk), participate in the VR walking 
simulator test or use the prism glasses 
 
Recruitment sources and procedures: 
The clinical trial will be conducted in two phases: a pilot phase during which participants will be 
recruited at Schepens Eye Research Institute and Massachusetts Eye and Ear, followed by the main 
phase when participants will be recruited at Mass Eye and Ear and other sites outside the MGB network.  
In this version of the protocol, recruitment sources and procedures are described in detail for the pilot 
phase at Schepens Eye Research Institute and Massachusetts Eye and Ear. Similar procedures will be 
used at other sites when they are added to the parent protocol. 
 
• 
Who is responsible (role on research team) for identifying and recruiting individuals 
Please see paragraphs below for details of who is responsible for identifying and recruiting 
participants for each of the recruitment sources. 
 
• 
When individuals are recruited 
Participants may be recruited at any time point providing it is at least 6 months since the onset of 
the HH. 
 
• 
Where individuals are recruited 
In the pilot phase of the clinical trial, subjects will be recruited at Schepens and Mass Eye and Ear 
from the following sources:  
 
1) Vision rehabilitation clinic at MEE  
Clinic staff will identify patients that meet our recruitment criteria. Clinic staff will present details 
about the study to potential subjects when they attend the clinic. Clinic staff will use the information 
sheet in our recruitment pack (described below). The potential subject can then either contact us 

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directly (using the contact information on the information sheet) or can complete the permission-to-
be-contacted form (part of the recruitment pack described below) and give the form to a clinic staff 
member. Completed permission-to-be-contacted forms will be returned by clinic staff to the study 
coordinator.  A study team member (study coordinator or research assistant) will then contact the 
patient by telephone about the study (Telephone script). 
 
2) Other ophthalmology and rehabilitation clinics in the MGB network 
This will primarily involve recruitment from rehabilitation clinics at Spaulding. Procedures for 
recruitment will be the same as described in (1) above.  
 
3) The vision rehabilitation clinic of Dr. Peli at Tufts  
Dr. Peli’s clinic at Tufts is outside the MGB network. However, Dr. Peli holds appointments at both 
Tufts and Schepens. (Please see the uploaded letter from the Department Chief at Tufts in support 
of recruitment from Dr. Peli’s clinic at Tufts). The methods for recruitment are similar to those 
described in (1) above.  Dr Peli will identify patients that meet our recruitment criteria. Then either 
Dr. Peli or the receptionist at the front-desk assisting in Dr Peli’s clinic will inform eligible patients 
about the study after the patient completes their appointment at Dr. Peli’s clinic. Eligible patients 
will be given the information sheet from the recruitment pack. They can then either contact us 
directly (using the contact information on the information sheet) or can complete the permission-to-
be-contacted form and return it to Dr. Peli (or the staff at his clinic’s front desk who will forward it to 
Dr. Peli). Dr. Peli will then give it directly to study staff at Schepens.  
 
4) Using personalized letters mailed to patients found using the RPDR  
We will use the RPDR database to screen subjects who have not opted out of receiving information 
about suitable studies. We will query the database to include patients from any hospital site in 
Massachusetts that is included in the database. Patients with an ICD code of Homonymous 
Hemianopia who are alive and do not have ICD codes of other physical or cognitive disabilities or 
visual impairments listed, and do not have interpreter services mentioned on the list will be 
contacted first. We will begin by contacting 100 subjects in chronological order from most recent to 
older encounter dates. The research assistant on the study team will use the RPDR database to 
query this data. Dr. Alex Bowers will be the workgroup leader and approve these requests to receive 
mailing information of potential subjects to contact. Personalized letters will be mailed out to these 
potential subjects. (Recruitment letter attached). Persons responding with interest in learning about 
the study can contact the research assistant or study coordinator on the phone and they will use the 
telephone script (attached) to explain the study to the participant. 
 
5) Subjects who participated in prior studies in Dr. Peli’s lab  
Subjects with HH may also be recruited from the pool of volunteers who have previously 
participated in studies in Dr. Peli’s lab and who have given their permission to be contacted about 
future studies. Contact information for subjects interested in participating in future studies is held in 
a secure database on the network. Participants identified from this database will be contacted 
directly by phone by the coordinator or the research assistant from the study to tell them about the 
study. (Telephone script) 
 
6) Study listing on websites and social media:  
In addition, we might list our study on social media platforms relevant to patients with hemianopia. 
We will contact the host of each platform and request that information about our study be listed 

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and, if possible, that chat and comment features be disabled. Participants recruited in this fashion 
will contact us directly either by phone or by using our recruitment email address. Potential 
participants who respond to this study listing will then be contacted directly by phone by a study 
team member (Telephone script). In the interest of privacy/confidentiality, there will be no 
interaction or answering of questions via posts and/or commenting features on the platforms. 
 
• 
Recruitment Pack  
The pack includes an information letter for the practitioner, an information sheet about the study 
for the patient and a Permission-to-be-contacted form for disclosure of the subject’s contact 
information. Potential participants can either complete the Permission-to-be-contacted form which 
will be returned to the study coordinator by the healthcare provider, or the patient can contact the 
study coordinator directly by phone. The coordinator or research assistant from the study will call 
patients who complete the contact form and give them further information about the study and will 
schedule a screening visit if the person is interested in participating. (Telephone script attached) 
 
• 
Methods to reduce risks of coercion or undue influence 
For participants who are among Dr. Peli’s own patients, the risks of coercion or undue influence will 
be minimized by having one of the study staff contact the patient about the study upon receiving a 
permission-to-be-contacted form and give them further information about the study. If the 
potential subject has additional questions about the study, then they can talk with co-investigator, 
Dr. Bowers, who is an optometrist (licensed to practice in the UK). Thus Dr. Peli will be directly 
involved when one of their patients is making a decision about whether to participate in the study.   
 
• 
How recruitment goals match the prevalence rates of the condition/disease being studied and the 
populations most impacted by the condition/disease being studied? 
Hemianopia affects both genders and members of all racial and ethnic groups. Therefore, during this 
study, no individuals will be excluded based on race, ethnicity or gender, and every attempt will be 
made to ensure that minorities and women meeting the eligibility criteria are recruited for 
participation. It is expected that approximately equal numbers of males and females will be recruited. 
There are some racial/ethnic group differences in the prevalence of certain diseases that cause 
hemianopia and we expect that this will be reflected in the sample populations that we recruit.  
 
• 
Methods to enhance enrollment of diverse individuals and under-represented populations 
We are not proposing any specific outreach programs for recruiting specific gender, racial and ethnic 
groups, as all eligible participants will be recruited regardless of gender, race and ethnicity. 
 
 
5. Subject Enrollment 
 
Pre-screening  
Subjects will not be prescreened  
 
Consent process: 
• 
When and where informed consent will be obtained  
Informed consent will be obtained at the start of the first visit. Consent procedures will be 
conducted in a quiet, private area at the study site by a trained member of the study team. Before 
the first visit all potential participants will be given an opportunity to receive a copy of the consent 

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form (by email or mail). During the subject’s first visit, the research assistant or site-specific staff 
administering the consent forms will discuss the forms on site and address any concerns related to 
the study procedures. Subjects will be given ample opportunity to discuss all aspects of the study 
and ask questions before signing the form. The forms will be signed by the subject on-site only. 
However, subjects are not obligated to sign the form on the same day and may choose to take time 
to decide before signing the forms. 
 
• 
Consent process for minors and children  
In the case of minors (age <18 years old), at least one parent or guardian will undergo the consent 
process with the subject and will be requested to sign the consent form. The subject will sign the 
consent form (age ≥ 14 years) or child assent form (7-13 years) as appropriate for the age. If a 
subject turns 18 years of age while taking part in this study, we will ask them  to sign a new consent 
form at that time. 
 
• 
The process for obtaining consent from non-English speakers if applicable 
N/A 
 
• 
The process to determine capacity to consent and use surrogate decision makers if applicable 
N/A 
 
• 
Procedures to minimize undue influence to enroll investigators’ own patients 
If a participant is a patient of one of the investigators, that investigator will not be directly involved 
in the consent process and will not be in the room during signature, to prevent any sense of 
pressure/coercion.   
 
• 
Post-consent intervention assignment and randomization method  
Participants who meet the eligibility criteria will be randomly assigned to sequence AB or BA. The 
allocation will be performed using software that implements the process of minimization. In 
minimization, the first participant is assigned randomly with each subsequent participant assigned in 
such a way as to approximately balance the two sequences for age and study site. Letter codes, 
randomly assigned to each of the treatment allocations by Dr. Jae-Hyun Jung, will be used by the 
software. The code breaker will be kept in a sealed envelope in a locked file cabinet in one of Dr. 
Jung’s rooms at Schepens. Dr. Jung is a member of the study team who is neither involved in data 
collection nor statistical analysis of the data. Data provided to the masked person conducting 
statistical analyses will use the letter codes to identify treatment allocation.   
 
 
6. Study Procedures 
 
 
Study devices   
Fresnel peripheral prism glasses and multi-periscopic prism glasses will be supplied for each subject. 
 
• 
Fresnel peripheral prism glasses (FPP) 
FPP glasses (Fig. 1) comprise Fresnel prism segments embedded as peripheral prisms in a 
prescription carrier lens, providing about 30° image shift. FPP glasses, known as the “Peli lens”, are 
commercially available from Chadwick Optical. They will be manufactured by Chadwick Optical for 
the study participants, including their individual prescription for spectacles. 

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• 
Multi-periscopic prism glasses (MPP):  
MPP glasses (Fig. 2) comprise a series of half-penta prisms (commonly used in binoculars) that provide 
45° image shift. The half-penta prisms are assembled using 3D-printed modules and then mounted in 
spectacle carrier lenses as peripheral prisms. MPP glasses will be assembled by Chadwick Optical for 
study participants, including their individual prescription for spectacles. 
 
• 
Method of administration 
The FPP and MPP glasses manufactured by Chadwick Optical will be sent directly to the study sites 
and stored in a secure location at each site. Prism glasses will be fitted to subjects by study staff at 
each site. Each pair of prism glasses is unique and can only be used by the subject for whom they were 
made. There will be no re-use of prism glasses by other subjects. After a subject finishes study 
participation, any study glasses not being used by the subject will be returned to Chadwick Optical for 
recycling.  
 
Description of each study visit and procedures, and schedule of assessments 
The following provides a summary of each visit and procedures. The timing of each visit is summarized in 
Table 1. The majority of data collection will be performed using standard clinical tests or questionnaires. 
The virtual reality (VR) walking simulator test, which will be the main outcome measure for the clinical 
trial, is described in detail below. Other standard clinical tests are not described in detail. 
 
• 
Visit 1: Screening and measurements for prisms 
‒ 
Informed consent 
‒ 
Visual acuity 
‒ 
Visual fields 
‒ 
Tests for hemispatial neglect (Bells test and Schenkenberg Line Bisection) 
‒ 
Test of cognitive status (Short portable mental status questionnaire) 
‒ 
Ocular and other relevant history  
‒ 
Ocular examination (or ocular examination within prior 6 months) 
‒ 
Refraction to verify spectacle prescription (or refraction within prior 3 months) 
‒ 
Clinical tests of binocular status (as necessary) 
‒ 
Fitting measurements for prism glasses including use of a photograph: After selecting a suitable 
spectacle frame for the subject a photo will be taken for reference measurements (the photo 
will only show one eye and the frame around that eye; Figure 3). 
 

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Figure 3: A reference photo to document the location of the pupil with respect to the frame. The person 
taking the photo will zoom in as much as possible so that the photo includes only the eye and frame on 
the side that the prisms will be fitted. If needed, the photo will be cropped to exclude any other facial 
features. Only the cropped photo will be stored. This photo will be referenced with the subject’s study 
ID code and included with the order for prism glasses sent to Chadwick Optical by study staff at 
Schepens 
 
 
• 
Eligibility determination 
After Visit 1, study staff at Schepens, supervised by Dr. Peli or Dr. Bowers, will review the results of 
the screening tests and make a decision about eligibility.  Eligible participants will then be assigned 
to sequence AB or BA using minimization by a member of the study team at Schepens and the study 
site will be informed.   
 
• 
Manufacture of prism glasses 
A pair of FPP glasses and a pair of MPP glasses will be manufactured for each eligible participant by 
Chadwick Optical. Schepens will prepare the order for prism glasses based on the measurements 
taken at Visit 1 and send the order directly to Chadwick, including the reference photo to document 
the location of the pupil with respect to the frame. After manufacture, study glasses will be sent by 
Chadwick Optical to the study site. Study ID codes will be used on all orders for prism glasses 
(participant names will not be used). We anticipate that it will take about one month for the study 
glasses to be manufactured and sent to the study sites.  
 
• 
Visit 2: Fitting first pair of prism glasses 
‒ 
Mobility questionnaire (rate level of difficulty in various situations without prism glasses)  
‒ 
Fit first pair of glasses 
‒ 
Photo to document fitting of first pair of prism glasses (includes only the eye and frame on the 
side the prisms are fitted) 
‒ 
Training in how to use the first pair of glasses, including a walk through corridors and rooms, 
accompanied by a member of the research team  
‒ 
VR walking simulator test (practice without prism glasses) 
 
• 
Home use - first pair of prism glasses  

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Subjects will use the first pair of prism glasses in everyday mobility as much as possible for about 
four weeks. They will receive a telephone call about one week after visit 2 to review how they are 
using the prism glasses, answer any questions they may have, and check for any adverse events that 
might have occurred. 
 
• 
Visit 3: Evaluation of performance with first pair of prism glasses and fitting second pair 
‒ 
Visual fields (without and with first pair of glasses)  
‒ 
VR walking simulator test (without and with first pair of glasses, order counterbalanced)  
‒ 
Mobility questionnaire and device questionnaire (for first pair of glasses) 
‒ 
First pair of glasses will be retained at the study site 
‒ 
Fit second pair of prism glasses 
‒ 
Photo to document fitting of second pair of prism glasses (includes only the eye and frame on 
the side the prisms are fitted) 
‒ 
Training in how to use second pair of glasses including a walk through corridors and rooms, 
accompanied by a member of the research team 
 
 
• 
Home use - second pair of prism glasses  
Subjects will use the second pair of prism glasses in everyday mobility as much as possible for about 
four weeks. They will receive a telephone call about one week after visit 3 to check that they are 
using the prism glasses, answer any questions they may have and check for any adverse events that 
might have occurred. 
 
• 
Visit 4: Evaluation of performance with second pair of prism glasses and clinical decision 
‒ 
Visual fields (without and with second pair of glasses)  
‒ 
VR walking simulator test (without and with second pair of glasses, order counterbalanced)  
‒ 
Mobility questionnaire and device questionnaire (for second pair of glasses) 
‒ 
Comparison questionnaire (compare two pairs of prism glasses) 
‒ 
Clinical decision by practitioner about whether subject should continue with MPP, FPP or no 
prisms (based on practitioner’s clinical judgment, subject’s preference and if performance with 
the prism glasses is not worse than the performance without the prism glasses during the study 
visits).   
 
• 
Optional extended wear with long term follow up 
Subjects who have a clinical decision to continue and wish to continue with either the MPP or the 
FPP glasses will be invited to participate in the extended wear phase of the study. Participants in the 
extended wear phase will receive a follow up telephone call about 6 months after Visit 4 and again 
about 12 months after Visit 4 to determine whether they are still using the prism glasses. If a subject 
is having difficulties with the prism glasses during the extended wear phase, a study visit to review 
the problems will be arranged if necessary. Otherwise there will be no in-person study visits during 
the extended wear period.  
If a subject is interested in continuing with prism glasses, but not willing to participate in the 
telephone follow ups, they will not be able to participate in the extended wear trial and the study 
team will retain both pairs of prism glasses. (They could, however, be fitted with prism glasses by 
their eye doctor outside of the study as part of clinical management of their condition). Based on 

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prior experience, we believe that it is highly unlikely that a subject who wants to continue with 
either the FPP or MPP glasses will not be willing to receive the follow-up phone calls. Completion of 
the extended wear part of the study is the best way for us to determine whether it is appropriate for 
the subject to continue to wear prism glasses in the long term. 
We believe that this is in the participant's best interests. Based on prior experience of two multi-
site trials of the FPP glasses for hemianopia, it is highly unlikely that a participant who wants to try 
the prism glasses in the longer term would not be willing to participate in the extended wear part of 
the study, which involves only 2 telephone calls. 
There will be no long term follow up for subjects who do not have a clinical decision to continue 
with either the MPP or FPP glasses.  
At the end of study participation, all subjects will return to the routine care of their eye doctor. 
 
Rationale for permitting subjects to keep glasses only after the end of the extended wear period: By 
the end of the crossover period, participants will only have worn each pair of prism glasses for 4 
weeks. This is a relatively short period of time. It is long enough to evaluate whether it is clinically 
appropriate for them to continue with prism glasses in the extended wear phase of the study, but 
not long enough to determine whether they should continue with glasses in the long term. It is only 
after participants have worn prism glasses for an extended period (more than 4 weeks) that we will 
be able to fully determine whether they should continue to use glasses in the long term after the 
end of the extended wear part of the study.  Therefore, participants will only be permitted to keep 
glasses after the end of the extended wear part of the study. 
 
 
Table 1: Schedule of visits and assessments 
 
 
 
 
Visit 1 
 
Visit 2 
Day 1  
1-week follow up 
Day 8 ± 3 
Visit  3 
Day 29 ± 7 
1-week follow up 
Day 36 ± 3 
Visit  4 
Day 57 ± 7 
6 month follow up 
Day 225 ± 21 
1 year follow up 
Day 393 ± 21 
Informed Consent 
X 
 
 
 
 
 
 
 
Visual acuity 
X 
 
 
 
 
 
 
 
Visual fields without prism glasses 
X 
 
 
X 
 
X 
 
 
Visual fields with prism glasses 
 
 
 
X 
 
X 
 
 
Neglect tests 
X 
 
 
 
 
 
 
 
Cognitive status test 
X 
 
 
 
 
 
 
 
Ocular and other relevant history 
X 
 
 
 
 
 
 
 
Ocular examination 
X 
 
 
 
 
 
 
 
Refraction 
X 
 
 
 
 
 
 
 
Binocular status tests 
X 
 
 
 
 
 
 
 
Measurements for prisms with photo 
X 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Fit and train in use of prism glasses 
 
X 
 
X 
 
 
 
 
Photo to document fitting of prisms 
 
X 
 
X 
 
 
 
 
VR walking simulator practice 
 
X 
 
 
 
 
 
 

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Visit 1 
 
Visit 2 
Day 1  
1-week follow up 
Day 8 ± 3 
Visit  3 
Day 29 ± 7 
1-week follow up 
Day 36 ± 3 
Visit  4 
Day 57 ± 7 
6 month follow up 
Day 225 ± 21 
1 year follow up 
Day 393 ± 21 
VR walking simulator data collection 
 
 
 
X 
 
X 
 
 
Mobility questionnaire 
 
X 
 
X 
 
X 
 
 
Device questionnaire 
 
 
 
X 
 
X 
 
 
Comparison questionnaire 
 
 
 
 
 
X 
 
 
Clinical decision on keeping glasses 
 
 
 
 
 
X 
 
 
 
 
 
 
 
 
 
 
 
Telephone follow up 
 
 
X 
 
X 
 
X 
X 
 
 
 
 

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Data collection methods and variables 
• 
Clinical tests and questionnaires 
At each visit, results of clinical tests and responses to questionnaires will be recorded by study staff 
at each site on the relevant data collection sheets (included as attachments). Electronic scanned 
copies of the data sheets will subsequently be sent to Schepens by secure data transfer for review 
and analysis. 
 
• 
VR walking simulator 
Each study site will have an identical set up for the VR walking simulator, comprising a large TV 
screen and a laptop computer with test software installed (Fig 4). Subjects will be asked to stand (or 
sit) in front of the TV screen. For subjects who stand, there will be a high walking frame to provide 
support and help maintain the correct position (Fig 4).  A video that simulates walking through a 
busy mall with other pedestrians will be displayed on the TV screen (Fig 4). Subjects will watch the 
video and push a joystick when they see a pedestrian which might collide/walk into them (push the 
joystick in the direction from which the pedestrian is approaching). They will also be asked to 
perform a task to control gaze location, which will involve looking at a fixation target and calling out 
occasional numbers within a string of letters they see displayed on the fixation target (Fig 5). 
Subjects will have an opportunity to practice the tasks before experimental data collection 
commences. Each video will be about 4 to 5 minutes in duration and subjects will be able to take a 
break whenever they need to. Data from the VR walking simulator (e.g., timing of button press 
responses) will automatically be recorded as numeric data by the software and saved in an 
electronic file, which will subsequently be sent to Schepens by secure data transfer to which only 
the study personnel will have access. Performance will primarily be quantified in terms of detection 
rates for colliding pedestrians and response times (from pedestrian appearance to the button press 
response). Other variables, such as the distance of the pedestrian at the time of the button 
response, might also be computed. 
 
 
 
Figure 4: VR walking simulator set up with 
large TV screen on a height adjustable table 
and a high walker with arm rests for 
support. Joysticks (to record participant 
responses) are mounted on the ends of the 
arm rests.  
 
 

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Figure 5: Sample screen shot of a VR walking simulator video from the participant’s perspective (spanning 110° 
horizontally) showing multiple pedestrians walking in a virtual shopping mall. The participant’s walking path is 
denoted by the green markers on the floor. There is an overtaken colliding pedestrian on the left and multiple 
non-colliding pedestrians on both sides.  In this example, the participant would be asked to call out numbers 
that appear in the yellow square at the gaze point, as well as to push the joystick when they see a pedestrian 
likely to collide with them.  When looking straight ahead without the prism glasses, a participant with HH will 
see the scene on only one side of their walking path. 
 
 
Plans for return of research results    
There are no plans to return research results to subjects at the end of the study. If subjects indicate an 
interest in the outcome of the study, a note-to-file will be made, and the PI may share the final 
published manuscript with these study participants. 
 
Primary and secondary outcomes   
• 
Primary outcome measure: Our primary outcome measure will be the improvement (binary, yes/no) 
in collision detection with prism glasses for pedestrians approaching from the blind side at a bearing 
angle of 40 (within the expansion range of MPPs but not FPPs).  Improvement will be defined as 
blind-side detection rates that are significantly higher with than without prisms at the same visit (p < 
0.05; z-test for two proportions) for correct detections with a timely response (more than 1 second 
until the collision point). 
• 
Secondary outcome measures: The secondary outcomes will include 1) improvement in detection 
with prism glasses for pedestrians approaching from the blind side at a bearing angle of 20 (within 
the expansion range of MPPs and FPPs), and 2) responses to the comparison questionnaire addressing 
device preference and comparison of the two devices for specific attributes such as helpfulness for 
obstacle avoidance and cosmetic appearance. We have included patient preference as one of the 
secondary measures because it reflects each patient’s self-determination of device efficacy based on 
their perception of device functionality in everyday mobility.  
 
Study termination criteria 
Study participation will be terminated and the prism glasses will be retained by the study team if: 

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• 
It becomes apparent that the subject is having difficulties with the prism glasses that could 
endanger the subject or others; 
• 
The subject no longer meets the inclusion criteria (e.g., becomes unable to walk during the course of 
the study); 
• 
The subject experiences a serious adverse event; 
• 
The subject reports any risky behavior while wearing the glasses such as driving or operating heavy 
machinery. 
 
Local site restrictions or site-specific procedures: 
All sites will use the same procedures. 
 
Description of what happens to participants when the study ends or if a participant’s 
participation in the study ends prematurely. 
At the end of the study, subjects will return to the routine care of their own eye doctor. If a subject’s 
participation ends prematurely, they will return to the routine care of their own eye doctor. 
 
Remuneration  
Subjects will not be reimbursed for time participating in study visits but will be reimbursed up to $50 per 
visit for transportation to Schepens Eye Research Institute/Mass. Eye and Ear. 
However, they will be permitted to keep one pair of prism glasses (that cost about $1000) at the end of 
the extended wear phase, if considered clinically appropriate. (Subjects who do not complete both 
periods of the crossover will be requested to return the prism glasses to the site.) 
 
Plans for receiving data from research collaborators outside Mass General Brigham  
In the first phase of the clinical trial (pilot data collection at Schepens and Mass Eye and Ear), data will 
not be received from collaborators outside of Mass General Brigham.  Once the multi-site sIRB protocol 
is implemented, data will be received from research collaborators outside MGB and will be transferred 
via a secure method (e.g., MGB Dropbox Business). All of the experimental data will be de-identified and 
will be labeled using only the subject’s study ID code. Only consent forms will have identifiable 
information. Consent forms will be electronically scanned, attested by the site personnel to be a true 
copy and sent to Schepens by the secure transfer method. 
 
Masking  
• 
Only the person conducting the statistical analyses will be masked to treatment allocation.  
• 
Study participants will not be masked as it would be impossible to do so.  (Information about FPPs is 
readily available on the internet so they could easily determine which pair of prism glasses was 
already commercially available). 
• 
Study team members fitting prism glasses, training participants to use prism glasses, and performing 
data collection will not be masked as it would be impossible to do so. These team members will all 
be knowledgeable about prism glasses and will easily be able to see whether participants are using 
the MPP or FPP glasses; the prism glasses have to be worn during data collection for the primary 
outcome measure. Given that the primary outcome measure is based on objective electronic data 
(rather than questionnaire data), we believe the risk that data collectors might bias the results is 
very low. (The primary outcome measure is based on performance in the VR walking simulator 
pedestrian detection task. Electronic data collected while the participant performs the test will be 
sent directly to Schepens for processing to derive the primary outcome measure.)  

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7. Risks and Discomforts 
 
All procedures in this study are minimal risk.  
Vision Tests: These are regularly performed for most eye exams.  
Prism glasses: There are some risks associated with using the prism glasses, but these are similar to the 
risks encountered when first wearing bifocal or progressive addition lenses. There may be a period of 
adjustment to the use of the new prism glasses during which the subject may find mobility more difficult 
and he/she may experience some discomfort.  These risks are minimized by fitting the prism glasses while 
the subject is seated, taking subjects for a supervised walk so that they can get used to the prism glasses 
before they take them home, providing take-home instructions on how to use the prism glasses, advising 
subjects to start by using the glasses in a familiar environment, advising subjects to always carry their 
regular glasses with them so that they can take the prism glasses off and wear their regular glasses if the 
prism glasses make them feel uncomfortable in any situation, and advising subjects not to drive or operate 
heavy machinery when wearing the prism glasses.   
VR walking simulator pedestrian detection task:  There is a slight risk that some people may experience 
slight and temporary motion sickness from viewing video backgrounds with simulated motion. There will 
be programmed breaks in testing sessions, which will help to reduce the risk of motion sickness, and 
subjects will be able to take a break at any time if they become uncomfortable.  
Confidentiality: Procedures to minimize risks to confidentiality include recording demographic and 
contact information on a separate form from the rest of the experimental data, storing in locked file 
cabinets all forms or records with information about a subject that would allow identification, and the use 
of unique subject identifier codes on all experimental research data forms and electronic data files.  Any 
electronic data files that would allow subject identification will be password protected on a secure server 
at each site.  Except for the consent form, all data transferred from the clinical sites to Schepens will be 
de-identified and will be transferred via a secure method. Any photographs taken of the subject to verify 
the position of the frame on the face will include only one eye and the position of the frame around that 
eye (i.e., the photo will be de-identified). Other facial features or the full face will not be photographed.  
Each site will be provided with a mobile phone to capture the photo. The phone will not be connected to 
any internet or mobile networks. The study personnel will transfer the photo to a PowerPoint slide with 
instructions to crop unnecessary identifiable information that may inadvertently be included in the photo 
and only save the cropped version. Each site will be provided with a laptop encrypted at MGB which will 
be used to run the software and log the data for the VR walking simulator test.  
 
8.  Benefits 
 
Potential Benefits to Participants: Subjects will get to take home and try two pairs of prism glasses (retail 
cost of $1000 or more for each). The glasses may help them to detect and avoid collisions with obstacles 
when walking resulting in safer mobility during everyday activities. At the end of the study, they may be 
allowed to keep one pair of glasses, if clinically appropriate, which may continue to help them in the longer 
term to detect obstacles when walking. 
 

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Potential Benefits to Society: Demonstrating efficacy of the MPP glasses will give patients with HH 
access to a new type of glasses having much better image quality and greater expanded field of view 
compared to those currently in the market. We expect that the use of these glasses will help patients 
with HH detect obstacles on their blind side and therefore aid safer mobility in everyday situations. 
 
 
9. Statistical Analysis 
 
Data analysis plan  
The differences in blind-side detection improvement rates between MPPs and FPPs will be analyzed 
using a McNemar test for data combined across both periods of the crossover, testing the hypotheses 
that improvements rates will be higher with MPPs than with FPPs at the 40° bearing angle (primary 
hypothesis) but will not differ at 20° (secondary hypothesis). An intention to treat analysis will be used.  
Participants who withdraw after treatment allocation but before the end of the crossover will be 
categorized as no improvement for both types of prism glasses. Questionnaire responses will be 
analyzed with non-parametric statistics. An α-value ≤ 0.01 will be considered to indicate statistical 
significance for the primary analysis and ≤ 0.05 for the secondary analyses 
 
Sample size estimate: 
The sample size calculation is based on results from a small pilot study (n = 6) conducted in Dr. Peli’s lab 
at Schepens in which participants with hemianopia completed measurements of collision detection 
using the same test as in the clinical trial. The sample size is computed for the primary outcome based 
on a McNemar test for a 2-by-2 contingency table of the binary improvement (yes/no) for MPPs and 
FPPs for detection of 40° pedestrians with data combined across both periods of the crossover. In the 
lab-based pilot study, 100% of participants improved with MPPs for the 40° pedestrians and 33% 
improved with FPPs. For the clinical trial, we anticipate that some participants will not show 
improvement with MPPs, and the overall effect size will be smaller. We therefore estimate that 70% of 
participants will improve with MPPs and 25% will improve with FPPs. The minimum sample size to 
detect a 45% difference between the proportion of participants improving with MPPs and FPPs is 36 
participants, assuming 20% overlap (i.e. improved with both MPPs and FPPs), power of 90% and 
significance (alpha) level of 1%, 2-tailed test. Allowing for 30% failing to meet inclusion criteria and 20% 
attrition after starting the clinical trial, we estimate a total sample size of 54 participants.  
Based on prior multi-site clinical trials of prism glasses for HH (Bowers et al., 2014), we expect 
that up to 30% of enrolled participants may fail to meet the inclusion criteria and 20% may withdraw 
after treatment allocation. Therefore, we will need to enroll at least 55 participants in total (as screening 
is done at the first visit).  In addition, prior to the main clinical trial, we plan to conduct a pilot of the 
clinical trial at Schepens and Mass Eye and Ear to verify study procedures and generate data to verify the 
sample size calculation. We plan to enroll 10 participants for the pilot clinical trial.  Therefore, the total 
enrollment will be 65 participants.  
 
 
 

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10. Monitoring and Quality Assurance 
 
Adverse event criteria and reporting procedures 
 
Criteria to define adverse events: 
This protocol uses the definition of adverse event from 21 CFR 312.32 (a): any untoward medical 
occurrence associated with the use of an intervention in humans, whether or not considered intervention-
related. 
• 
Serious adverse event means any event temporally associated with the subject’s participation in 
research that meets any of the following criteria:  
• results in death; • is life threatening (places the subject at immediate risk of death from the 
event as it occurred); • requires inpatient hospitalization;  • results in a persistent or significant 
disability/incapacity; or • any other adverse event that, based upon appropriate medical 
judgment, may jeopardize the subject’s health and may require medical intervention to prevent 
one of the outcomes listed above. 
 
Unanticipated Problems: 
Any incident, experience, or outcome that meets all of the following criteria:  
• 
It is unexpected (in terms of nature, severity (see severity grades below), or frequency) given 
(a) the research procedures that are described in the protocol-related documents, such as 
protocol and informed consent documents; and (b) the characteristics of the subject 
population being studied;  
• 
It is related or possibly related to participation in the research (possibly related means there is 
a reasonable possibility that the incident, experience, or outcome may have been caused by 
the procedures involved in the research); and  
• 
It suggests that the research places subjects or others at a greater risk of harm (including 
physical, psychological, economic, or social harm) than was previously known or recognized. 
 
This definition could include an unanticipated adverse device effect, any serious adverse effect on 
health or safety or any life-threatening problem or death caused by, or associated with, a device, if that 
effect, problem, or death was not previously identified in nature, severity, or degree of incidence in the 
investigational plan or application (including a supplementary plan or application), or any other 
unanticipated serious problem associated with a device that relates to the rights, safety, or welfare of 
subjects (21 CFR 812.3(s)). 
 
Reporting Adverse events: 
All adverse events whether serious or non-serious, expected or unexpected, will be reported as soon as 
possible to the PI (Dr. Peli) or co-PI (Dr. Bowers) - by a subject or member of the research team.   
 
They will promptly review documented adverse events to determine 1) if the event should be classified 
as an adverse event: 2) if there is a reasonable possibility that the adverse event was caused by the 
study device(s); and 3) if the adverse event meets the criteria for a serious adverse event. 
 
Dr. Peli (PI) and Dr. Bowers (co-PI) will be responsible for determining whether an AE is expected or 
unexpected. An AE will be considered unexpected if the nature, severity, or frequency of the event is not 
consistent with the risk information previously described for the study device.  
 

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All AEs will have their relationship to the study device assessed.  The PI will determine the AE’s causality 
based on the temporal relationship and his/her best judgment. The degree of certainty about causality 
will be graded using the categories below.  
• 
Definitely Related – There is clear evidence to suggest a causal relationship, and other possible 
contributing factors can be ruled out.  
• 
Possibly Related – There is some evidence to suggest a causal relationship. However, other 
factors may have contributed to the event (e.g., the participant’s clinical condition, other 
concomitant events).  
• 
Not Related – There is no reasonable possibility that the study device caused the event, there is 
no temporal relationship between use of the study device and event onset, or an alternate 
etiology has been established.  
The severity of a non-serious, unexpected adverse event will be graded as follows: 
• 
Mild adverse event – Events that do not interfere with the participant’s daily activities.  
• 
Moderate adverse event – Events result in a low level of inconvenience or concern with the use 
of the glasses. Moderate events may cause some interference with regular activities related to 
mobility. 
• 
Severe adverse event – Events interrupt a participant’s usual daily activity but not potentially 
life-threatening or incapacitating.  Of note, the term “severe” does not necessarily equate to 
“serious”. (For example: A person suffering a temporarily incapacitating injury such as a 
sprained ankle due to slipping on snow while wearing the prism glasses, even though the fall 
was not caused due to wearing the glasses) 
 
 
Any adverse events that are serious, unexpected and related or possibly related to the study will be 
reported to the Mass Eye and Ear IRB within 7 calendar days from the time the PI becomes aware of the 
event.  Any unexpected and study-related death will be reported to the Mass Eye and Ear IRB within 24 
hours of the PI’s knowledge of the event by e-mail or telephone. If there is any doubt as to whether an 
incident or observation is an AE, the event will be reported to IRB nevertheless based on the schedule 
described below. 
  
The PI will report events to the IRB based on the following schedule: 
• 
Possibly, Probably, or Definitely Related Expected AE – Report to IRB on annual basis 
• 
Possibly, Probably, or Definitely Related Expected Serious AE – Report to IRB within 7 days 
• 
Possibly, Probably, or Definitely Related Unexpected AE – Report to IRB within 30 days of event 
• 
Possibly, Probably, or Definitely Related Unanticipated Problem – Report to IRB within 7 days of 
event (24 hours for death or data loss) 
• 
Possibly, Probably, or Definitely Related Unexpected Serious AE – Report to IRB within 7 days of 
event (24 hours for death) 
 
 
Unanticipated Problem Reporting 
All UAPs involving risks to subjects or others will be reported to the Mass Eye and Ear IRB within 7 
calendar days from the time the PI becomes aware of the event. If a UAP or an unexpected Serious AE 
results in a subject’s death or was potentially life-threatening, the PI will notify the Mass Eye and Ear IRB 

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through e-mail or phone within 24 hours from the time the event is identified. A follow-up report will be 
submitted if applicable, at a later date when more information is available.  For UAPs that result in data 
loss the PI will notify the Mass Eye and Ear IRB through e-mail or phone within 24 hours from the time 
the UAP is identified.   
 
Planned safety monitoring 
The subjects in this study will not be participating in any activities that they would not otherwise 
participate in as a part of their daily life. The subjects are not expected to be exposed to any potential 
risks other than those commensurate with the fitting of prismatic devices in a regular low vision clinic. 
No irreversible effects of using prism glasses or effects related to the duration of use of the glasses have 
been reported in our experience so far. Given the minimal risk involved in participating in the study and 
the nature of the use of these glasses, the study will be primarily monitored for safety by the PI. An 
external safety monitor (Dr. Lotfi Merabet, OD, PhD, MPH) will also be appointed. Schepens Eye 
Research Institute will act as the data and safety monitoring center for the study. 
 
Monitoring for Off-site Adverse Events (Solicited and Unsolicited) 
The subjects will be instructed to report any adverse events to the study personnel through telephone 
or email as soon as they occur (Unsolicited report). The study personnel will interview the subject for 
the occurrence of any adverse event while wearing the prism glasses at home during the telephone 
follow-up (One week after providing the glasses) or during the return visit to the clinic (After 4 weeks of 
using the glasses). Events reported by the subject during these interviews will be noted as solicited 
adverse events. Personnel preparing the study safety logs will screen for double reporting of 
solicited/unsolicited events. 
 
Internal monitoring: 
Study sites will submit source data and data collection sheets to Schepens by secure file transfer after 
each subject visit (please see Description of Data management methods below). Internal monitoring of 
the source data documentation, completion of data sheets, protocol adherence, recording keeping will 
be carried out weekly by a research assistant (or other study team member) at Schepens under the 
supervision of Dr. Peli (PI) and Dr. Bowers (co-I). The research assistant will also note any documented 
AEs or UAPs. AEs or UAPs that occur on-site will be noted in the subject’s data sheets.  Additionally, a 
separate monitoring log of expected and unexpected events and any solicited or unsolicited AE report, 
will be kept and sent to the PI on a case-by-case basis (usually within 24 hours of the event occurrence). 
This monitoring log will be stored electronically. Non-compliance with protocol (e.g., failure to use the 
study checklist, complete data sheets correctly, or properly document or report in a timely manner 
adverse events) will be documented.  Once identified, minor issues will be addressed by the PI by special 
meeting or at weekly study meetings.  Special meetings may be called depending on the seriousness of 
the issue.  Repeated offenses will result in removal of that study staff from the protocol. Adverse events 
will be documented and reported to the IRB and NEI per the schedule described in the protocol.   
 
Outcomes monitoring, including planned frequency of review. 
Data summaries will be produced by the research assistant (including data on topics such as subject 
enrollment, withdrawals, primary outcome measures, and any safety issues) and reviewed by the PI and 
other study personnel during weekly study meetings. Approximately once a quarter, data summaries 
will be reviewed by an internal committee comprising the PI and members of the research team at 
Schepens to monitor data quality, primary outcomes and study progress.   
 

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Internal Data Safety Monitoring Committee and External Safety Monitor 
The PI will be the primary safety monitor for this study. An internal data safety monitoring committee 
consisting of the PI, co-investigator (Bowers) and other members of the study team at Schepens will 
periodically review the study reports internally as mentioned above. Additionally, an external safety 
monitor, Dr. Lotfi Merabet, OD, PhD, MPH, who has no conflict of interest with the study will be 
appointed (please see uploaded letter and CV). Dr. Merabet is a clinician-scientist with specialist 
expertise in rehabilitation of patients with brain injuries and clinical trial experience. He will review 
safety monitoring reports prepared by the research assistant about twice a year. These reports will 
include data on aspects such as subject enrollment (numbers screened and enrolled), subject losses 
(numbers withdrawn or lost to follow up), data form completion, clinical outcomes (number of subjects 
advised to continue with the study devices, or to continue without devices after completion of the 
study), and any safety issues.  
 
Study stopping rules as applicable 
There are no study stopping rules (other than the criteria for terminating a subject from the study, 
detailed in the section on study termination criteria above)  
 
Independent monitoring of source data as applicable:  
Not applicable 
 
Description of data management methods: 
Data collection sheets will be completed for each subject enrolled into the study.  Data collection sheets 
will be study visit specific and the study personnel preparing the weekly summaries for the PI will review 
the data sheets for completeness and document any minor protocol deviations.  
 
Subjects will be identified by a unique study ID code that will be used on all data sheets and electronic 
data files. Links between study ID codes and subject identifiers will be kept in a separate secure 
document in a secure location at the site where the subject was recruited. The code that links 
information that can identify the participant to the data collected for this research will be kept separate 
from their health information and will be destroyed once this study is complete and all manuscripts have 
been published. 
 
When study sites outside the MGB network are added to the protocol, personnel at the sites will scan 
de-identified datasheets and transfer them to Schepens using a secure file-sharing system that only the 
study team will have access to. Any deviations from protocol will be documented on a deviation log and 
communicated with the study site.  All computer-generated data will be de-identified and shared using 
the approved file sharing system along with the data collection sheets. Only the PI and researchers 
specific to this study who have been granted access to the data by the PI will be able to view the data.  
 
Originals of consent forms will be kept in a secure location at each site. Electronic scanned copies of 
consent forms, attested as true copies by study personnel, will be sent to Schepens by the secure 
transfer method. 
 
11. Select the Privacy and Confidentiality measures that apply to this research: 
☒ Study procedures will be conducted in a private setting 
☒ Only data and/or specimens necessary for the conduct of the study will be collected 

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☒ Data collected (paper and/or electronic) will be maintained in a secure location with appropriate 
protections such as password protection, encryption, physical security measures (locked 
files/areas) 
☒ Specimens collected will be maintained in a secure location with appropriate protections (e.g. 
locked storage spaces, laboratory areas) 
☒ Data and specimens will only be shared with individuals who are members of the IRB-approved 
research team or approved for sharing as described in this IRB protocol 
☒  Data and/or specimens requiring transportation from one location or electronic space to 
another will be transported only in a secure manner (e.g. encrypted files, password protection, 
using chain-of-custody procedures, etc.) 
☒   All electronic communication with participants will comply with Mass General Brigham secure 
communication policies 
☒ Identifiers will be coded or removed as soon as feasible and access to files linking identifiers 
with coded data or specimens will be limited to the minimal necessary members of the research 
team required to conduct the research 
☒ All staff are trained on and will follow the Mass General Brigham policies and procedures for 
maintaining appropriate confidentiality of research data and specimens 
☒ The PI will ensure that all staff implement and follow any Research Information Service Office 
(RISO) requirements for this research 
☐ Additional privacy and/or confidentiality protections 
 
 
 
12. References 
 
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and diplopia when prescribing prisms for homonymous hemianopia. Translational vision science & 
technology, 2(4), 2-2. 
Bowers, A. R. (2016). Driving with homonymous visual field loss: a review of the literature. Clinical and 
Experimental Optometry, 99(5), 402-418. 
Bowers, A. R., Houston, K. E., Goldstein, R. B., & Peli, E. (2014). Peripheral prisms and training improve 
detection of pedestrians by drivers with hemianopia. Investigative Ophthalmology & Visual Science, 
55(13), 2155-2155. 
Bowers, A. R., Keeney, K., & Peli, E. (2008). Community-based trial of a peripheral prism visual field 
expansion device for hemianopia. Archives of ophthalmology, 126(5), 657-664. 
Bowers, A. R., Keeney, K., & Peli, E. (2014). Randomized crossover clinical trial of real and sham 
peripheral prism glasses for hemianopia. JAMA ophthalmology, 132(2), 214-222. 
Chen, S. C., Suaning, G. J., Morley, J. W., & Lovell, N. H. (2009). Rehabilitation regimes based upon 
psychophysical studies of prosthetic vision. Journal of neural engineering, 6(3), 035009. 
Freeman, E. E., Munoz, B., Rubin, G., & West, S. K. (2007). Visual field loss increases the risk of falls in 
older adults: the Salisbury eye evaluation. Investigative ophthalmology & visual science, 48(10), 
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Giorgi, R. G., Woods, R. L., & Peli, E. (2009). Clinical and laboratory evaluation of peripheral prism glasses 
for hemianopia. Optometry and vision science: official publication of the American Academy of 
Optometry, 86(5), 492. 

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Houston, K. E., Peli, E., Goldstein, R. B., & Bowers, A. R. (2018). Driving With Hemianopia VI: Peripheral 
Prisms and Perceptual-Motor Training Improve Detection in a Driving Simulator. Translational vision 
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