Visual Rehabilitation After Retinal Prosthesis Implantation: An 18-month Case Report,From Candidate Selection to Follow-Up

Abstract

Introduction: Various retinal implants are being developed and appear to be a promising option for improving the visual capacities of individuals with retinal dystrophy. A multidisciplinary approach to both assessment of a candidate’s factors and rehabilitation could contribute to improved activity and participation. The purpose of this study was (i) to document the approach taken by a multidisciplinary team in the candidate selection process and in training in the use of the Argus II retinal prosthesis system (RPS), and (ii) to examine the effects of the RPS on sensory and mental functions and on activity and participation. Methods: An A1-B1-A2-B2 experimental case report was used, with repeated measures pre- and post-rehabilitation program design. The A phases represent the periods with the system off, whereas the B phases represent the periods with the system on. A 65-year-old man with retinitis pigmentosa and total blindness was followed by a multidisciplinary team for over 18 months. After receiving the retinal implant, he benefited from a 10-week rehabilitation program (twice per week; B1 phase). Results: Globally, the RPS improved vision in the B phases when the system was on and visual acuity was stable at 2.3 logMAR (functional blindness). The participant’s mental and neuromusculoskeletal function scores were generally stable throughout the data collection periods. Lower performance on some measures at the end of phase B2 coincided with a negative mood. Discussion: Use of the RPS improved activity, but this did not transfer into greater participation in the living environment. Despite efforts made by the rehabilitation team to manage the user’s expectations concerning the RPS, the interventions reactivated his grieving over his vision loss. Implications for Practitioners: New technologies can make users dream of unrealistic possibilities, and managing their expectations requires problem solving supported by a multidisciplinary team.

Keywords

visual prosthesis patient care team patient participation retinitis pigmentosa rehabilitation

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Retinitis pigmentosa (RP) is a disease that causes blindness following progressive degeneration of the retina. It affects about one in 4000 people (Garip & Kamal, 2019). These individuals live with a participation restriction (Garip & Kamal, 2019), and there is currently no effective treatment for RP. Some interventions are in development (e.g., cell transplantation, gene and nutrition therapy), but they have limited efficacy (He et al., 2015). Recently, various retinal implants have also been developed. They seem promising for improving the visual capacities of these individuals and may improve their activities (Ayton et al., 2020; Dagnelie et al., 2017a).

The Argus II retinal prosthesis system (RPS; Second Sight Medical Products, Sylmar, CA, USA) is one such technology. It uses a 60-electrode chip that is surgically implanted in the eye and connected to a camera attached to eyeglasses (see description of the system elsewhere; Ho et al., 2015). Studies conducted with the device show modest vision improvement with mean acuity values of 2.5 logMAR (Ho et al., 2015) and visual fields of approximately 20 degrees (Markowitz et al., 2018). However, results vary (Zrenner & Birch, 2015), partly due to the selection of candidates. Therefore, some authors (Farvardin et al., 2018; Finn et al., 2018; Markowitz et al., 2018) proposed guidelines for assessing candidates and post-operative interventions. Ghodasra et al. (2016) suggest that the rehabilitation team that assesses candidates may have a positive effect: Farvardin et al. (2018) found that a multidisciplinary approach by a cross-functional team optimizes strategies and leads to better user outcomes. Moreover, the literature (Bentley et al., 2019; Markowitz et al., 2018) suggests that psychosocial factors be considered in candidate selection. Also, there seems to be a lack of appropriate assessment methods for this client group. Ghodasra et al. (2016) stresses that “rehabilitation efforts and correlation with validated outcome measures following implantation are critical.”

Finally, these studies show that use of the implant improves visual capacities. Although some studies have documented long-term effects (da Cruz et al., 2016; Geruschat et al., 2016), effects on psychological adjustment have not been addressed. In addition, the effects of the implant on participation, such as performance in activities in the community have not been evaluated. In this context, it is legitimate to ask whether a multidisciplinary approach to both assessment and rehabilitation could help improve activity and participation of implant recipients.

Objective

The objective was to track the functional and psychological development of a single Argus II RPS user over an 18-month period (i.e., pre-operative evaluation to 12 months post-rehabilitation, with multiple interdisciplinary rehabilitation interventions), and examine the effects of the RPS on sensory and mental functions, and on activity and participation. We sought also to report user’s views of the effects of the retinal implant.

Methods

Design

Originally, we planned an experimental case report with repeated measures pre- and post-rehabilitation, but due to a 27-day accidental disconnection of the system, the study was transformed into an A1-B1-A2-B2 design (Lanovaz, 2013). The A phases represent the periods with the system off, whereas the B phases were when the system was on.

Participant

The participant Mr. H was a 65-year-old male who lived in a rural area with his spouse. He owned a family business and was gradually retiring. He was a curious and analytical man who enjoyed reading and doing automotive repairs and renovations. He was diagnosed with RP at age 51 years. He gradually became completely blind and started to develop visual hallucinations corresponding to Charles Bonnet Syndrome (CBS). A previous article explored his CBS in relation to his RPS (Moore et al., 2020).

Mr. H had tried various therapies, including the so-called “revitalizing surgery” combined with ozonotherapy and electrostimulation, at 57 years of age. Shortly after this therapy, he received some vision rehabilitation, with the main objective of accessing written communication. Eight years after the surgery, he expressed interest in receiving an RPS, stating he wanted to advance science, decrease his CBS, and regain some vision.

This study was approved by the Research Ethics Committee of the Center for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR-1330-0418), and informed consent was obtained.

Setting

This study was conducted at the Institut Nazareth et Louis-Braille rehabilitation center (institute; Longueuil, Canada) for visually impaired persons. The implantation of the RPS was performed at Hôpital Maisonneuve-Rosemont (hospital; Montreal, Canada).

Procedure

To select this candidate for RPS, we relied on (i) data from the literature and (ii) the selection process previously developed by a team of 10 professionals from the rehabilitation center. Documented valid and reliable assessment tools (Finn et al., 2018) and clinical experience were used to assess Mr. H’s visual and mental functions (T0). Measurements were taken at two other times (T1 and T2), thus creating the baseline (A1; see Figure 1). One month after selection, between T1 and T2, two ophthalmologists performed the implantation of the retinal prosthesis. The system was activated and calibrated 40 days later at the rehabilitation center, with the assistance of the Second Sight team.

Figure 1.

Timeline and professionals’ involvement.

The first phase with the RPS on (B1) included a single measurement (T3). Eleven weeks after activation, it accidentally disconnected (A2). During this phase, assessments of the participant’s mental functions and capacities were performed (T4) and the RPS was replaced and programmed in an identical manner. Phase B2 involved reconnection of the system and three assessments were conducted up to 18 months after T0 (T5 to T7).

Each time, assessments were taken in a single day at the Institute and always in the same order. Mr. H first met with the psychologist (2 hours), then with the optometrist (1 hour), and after a lunch break he met with the occupational therapist (2–3 hours).

Training

The rehabilitation program aimed to help Mr. H learn how to effectively use the prosthesis system and develop the visual skills and strategies needed to accomplish various tasks. The program was provided by an interdisciplinary team composed of a low-vision therapist (LVT), an orientation and mobility (O&M) specialist, and an occupational therapist. Many interventions were co-performed by two professionals (LVT–O&M specialist or occupational therapist–O&M specialist). It included 20 training sessions each lasting from two to three hours, given twice per week for 10 weeks (see Figure 1). The first session took place 2 days after the RPS was activated.

The rehabilitation program was driven by Mr. H’s objectives and the literature (Geruschat et al., 2017; Markowitz et al., 2018). To master the device, Mr. H was trained to detect, localize, align, count, compare, identify, reach, get around, et cetera (see Figure 2) using various stimuli, facing a black wall and table, or in an empty white gym (150–350 lux).

Figure 2.

Exercises that were used during the training.

In week 20, the rehabilitation team met the participant and his spouse to refine the participant’s objectives and discuss the team’s views. Few realistic functional goals were identified for the intervention plan. Mr. H was already very independent, but orientation difficulties in his garage were targeted, since it was a room with a strong echo that caused difficulties in locating sound sources. A visual stimulus would therefore have allowed for a significant functional gain.

At week 21, the device was reprogrammed in an attempt to improve the perception thresholds.

The last intervention by the occupational therapist in phase B1 (week 22) occurred at the participant’s home to identify an area where the system would be useful and test it. The last intervention by the O&M specialist involved reviewing some cane techniques to help the participant in difficult areas. During phases A2 and B2, the participant no longer benefited from rehabilitation. During T5 to T7, the occupational therapist provided follow up and encouraged the use of RPS in daily activities.

Mr. H was offered psychological support interventions at the outset and on other occasions during rehabilitation, but always declined. However, during each assessment with the psychologist, he was given an opportunity to talk about his experience with the implant.

Data collected

The measurement tools used are presented in Table 1 according to the International Classification of Functioning, Disability and Health (ICF; World Health Organization, 2001). Measures were taken from 4 to 8 times over the course of the study to account for potential learning effects.

Table 1.

Measures and data collection times.

Measure	Administrator	Data collection times
		A1*			B1	A2*	B2
		T0*	T1*	T2*	T3	T4*	T5	T6	T7
A. Sensory Functions
1. BRVT		X	X	X	X	NA	X	X	X
2. Transilluminator	Optometrist	X	X	X	X	NA	X	X	X
3. Octopus perimeter	Optometrist	X	X	X	X	NA	X	X	X
B. Mental Functions
4. Beck Anxiety Inventory		X	X	X	X	X	X	X	X
5. Geriatric Depression Scale	Psychologist	X	X	X	X	X	X	X	X
6. MoCA-Blind	Psychologist or OT	X	X	X					X
7. Stuart Tactile Maps		X	X	X					X
8. Spatial relationships between objects (from OT-APST)	OT	X	X	X					X
C. Neuromusculoskeletal and Movement-Related Functions
9. Berg Balance Scale	OT	X	X	X	X	X	X	X	X
D. Activities and Participation
10. FLORA		X		X		X	X	X
11. ULV-VFQ 23	OT	X	X	X	X	X	X	X

* Columns A1 and A2 (and subcolumns T0, T1, T2, and T4) correspond to the collection times when the system was off. Note. OT = occupational therapist. NA = not available.

Sensory Functions (ICF-b2)

Light perception was assessed with a 3.5V transilluminator (Welch Allyn, Skaneateles Falls, NY, USA); visual acuity was tested with the Berkeley Rudimentary Vision Test (Bailey et al., 2012), and visual field was examined with an Octopus 900 perimeter (Haag Streit, Mason, Ohio, USA) in the kinetic examination mode with the V4e target. Because of the unexpected disconnection of the RPS, the participant’s visual function could not be assessed at T4.

Mental Functions (ICF-b1)

Mental functions were assessed with: the Beck Anxiety Inventory (BAI; Beck et al., 1988), the Geriatric Depression Scale (GDS; Yesavage, 1988), the MoCA-Blind (Wittich et al., 2010); Stuart Tactile Maps (STM; Finger et al., 2014; Stuart, 1995) and the Apraxia and Body Scheme subsections of the Occupational Therapy Adult Perceptual Screening Test (OT-APST; Cooke et al., 2006). For the MoCA-Blind and STM, considering potential learning effects and the participant’s relative stability on the first three measures, a single follow-up measure was taken at the end of the study.

Neuromusculoskeletal and Movement-Related Functions (ICF-b7)

Balance was measured using the Berg Balance Scale (Berg et al., 1992).

Activities and Participation (ICF-d) Activities

The Functional Low-Vision Observer-Rated Assessment (FLORA) (Geruschat et al., 2016) is an observer-rated measure of activities performed in the laboratory. Many tasks that could not be performed by the participant were not assessed, so as not to discourage him. Eighteen out of 35 tasks were selected, based on the participant’s goals and routine activities (Geruschat et al., 2016). Except for the baseline obtained before activating the RPS, the assessment was performed with the system on.

Participation

Participation was documented using the Ultra-Low Vision Visual Functioning Questionnaire 23 (ULV-VFQ 23; short form) (Dagnelie et al., 2017b). This test is based on the participant’s subjective perception of his ability to perform a task while using only his vision. Response options were “impossible,” “very difficult,” “somewhat difficult” and “easy.” At T4 (phase A2, during the disconnection), the question was adjusted as follows: “Just before the disconnection, were you able to….”

Participant’s Views

The participant’s views were obtained from the open-ended questions section of the FLORA.

Data analysis

Raw data were graphed for each measure pre- to post-program for all functions but sensory functions.

Data were analysed using the two standard deviation band method (SDB) when baseline scores were higher than 0 (Domholdt, 2000; Ottenbacher, 1986). Although this method is primarily intended for detecting a change in response level between baseline and treatment phases, it controlled for variations in test performances that might be attributed to causes external to the rehabilitation.

Results

The results are presented by ICF category. In the pre-program phase (A1), the participant was totally blind.

Sensory functions (a)

The results for visual function are presented in Table 2 and Figure 3. Globally, vision improved in the B phases (system on), and visual acuity was stable at 2.3 logMAR. At its best, the participant’s visual field was 12 × 12 and slightly declined over time. Figure 3 shows the participant’s visual field impairment.

Table 2.

Measures of visual functions.

Measure	Data collection times
	A1*			B1	A2*	B2
	T0*	T1*	T2*	T3	T4*	T5	T6	T7
VA trans	NLP	NLP	NLP	LP	NA	LP	LP	LP
VA BRVT logMAR	NLP	NLP	NLP	2.3	NA	2.3	2.3	2.3
VF horizontal (deg)	0	0	0	12	NA	12	10	9
VF vertical (deg)	0	0	0	12	NA	9	12	5

* Columns A1 and A2, and their associated subcolumns (T0, T1, T2, and T4), represent collection times when the system was off. Note. NLP = no light perception. LP = light perception. NA = not available.

Figure 3.

Participant’s visual field at T6.

Mental functions (b)

Using the SDB method, the visual analysis of the participant’s mental function scores generally revealed stability over time. However, the graph for the Beck Anxiety Inventory shows a peak at T4 (phase B1) corresponding to the period of accidental disconnection (Figure 4(a)). The graph for the Geriatric Depression Scale reveals that the participant's mood fluctuated within the limits of two standard deviations (Figure 4(b)), except for a slight peak at T7 (phase B2), thus suggesting a more negative episode. For the MoCA-Blind and Stuart Tactile Maps tests, only one follow-up measure (T7) was taken after baseline. For the MoCA-Blind (Figure 4(c)), the follow-up score remained between the limits of two standard deviations, but returned to its initial level right at the cut-off point for mild cognitive impairment (18/22). For the STM test (Figure 4(d)), the participant decided to end this test (T7) and, thus, scored under the SDB limits. The OT-APST scores (not shown) remained at a maximum during the study.

Figure 4.

Results on function and activity measures.

The alliance that developed during the study between Mr. H and the psychologist made it possible to gauge the psychological effect of the implant and enabled the psychologist to support him. Topics discussed at each session and observations were noted (Table 3). At the end of the whole process, Mr. H reported that these “times for discussion” were helpful, and even necessary.

Table 3.

Views of the psychologist and the participant.

Phase	Time	Observations on the psychological development of the participant	Report from the participant (qualitative section of the FLORA)
A1	T0	Motivational interview for an informed decision. The purpose of this interview was to better identify the participant’s expectations and to provide him with information about the implant itself and the rehabilitation work, thus enabling him to make an informed decision.
A1	T1–T2	Expectation and hope. Prior to surgery, the participant’s mental state was one of hope and optimism in relation to the experience that was about to begin. He also showed certain nervousness over the upcoming surgery. Nevertheless, the feeling of having nothing left to lose drove away the fears. His grief over his vision loss was an emotional experience that was still painful in some respects.
B1	T3	Disappointment and hope for rehabilitation. Dashed expectations were a factor that reactivated unresolved grief over vision loss and, combined with the significant increase in visual hallucinations, led to a host of negative affects. The participant’s self-esteem was shaken by the challenge of rehabilitation, and awoke in him a desire to be a good candidate for retinal implant; he felt privileged to have such an expensive device in his hands and to have been selected to receive it. He maintained a good level of motivation for the training in progress.	Usability. I use it here at the rehab center and at home. Elsewhere, I'm afraid it's too distracting, and I'm going to smash into something because I'm distracted by the information I’m getting from it.
A2	T4	Disillusionment. The system disconnection seemed to have a significant impact on the participant's mood. This was not because of loss of function, but because he feared being responsible for the breakdown of the device.The participant displayed disappointment and anger at the low functional gains. These results undermined his hope and motivation. Despite the feeling that he was doing everything possible to use the device properly, the participant was confronted with the impossibility of transferring the learning into his activities of daily living.
B2	T5–T6	Progressive gains. The participant took a more realistic view of the device's limitations and valued the efforts he had made to maximize his use of the device, even if the results were still disappointing. However, the participant was pleased that the rehabilitation made his family and friends more aware of his reality. He was proud of the energy he had invested in the experience and the contribution he had made to scientific research.	Usability. I have sniper vision, with a very small field, and when I'm on to something, it brings me flashes. I don't know what it is, and people around me don't always know what I'm looking at. It's hard for me to keep up with them. […] Moving along a line is nice here [laboratory], but when we tried it in my garage, the line on the ground, it was lost among the cracks in the concrete floor. So I didn't do the line in my garage.Unsatisfied expectations. Psychologically, there are days when I'm better off not playing with it. I'm disappointed. I expected more than that. But then again, that's part of the game. I know you told me about that, but I believed it anyway. […] The system gives me absolutely nothing. It entertains me and takes my mind off things, that's pretty much it. [I see] like water on a car hood. You see it, but you lose it easily. I see what's bright like a window, but the rest of it, well...
	T7	Mourning. The participant expressed frustrations and disappointments related to the retinal implant. He could no longer deny the loss and spoke in more detail about his disillusionment, that is, by admitting the permanent limitations imposed by the disability, but in a way that was easier to assimilate as he could identify his disappointment. The creative quest to regain balance was over. He reached an impasse, in much the same way as after his treatments in Cuba. He expressed the hope that he had been useful to science. He felt supported and valued by the rehabilitation team in the process.	Disappointment. A lot of disappointment. My expectations were higher; it's not what I expected. I was very satisfied at first. I was euphoric because I was seeing bright reflections. […] But I can't tell the real from the abstract in real life. The best was last summer, then it was no longer the same. […] As long as the device will send something, I'll keep using it. But I feel like I'm going to mourn that, too.

Neuromusculoskeletal and Movement-Related Functions (c)

For the Berg Balance Scale, visual analysis (Figure 4(e)) reveals that, while staying within the limits of two standard deviations, balance scores increased slightly through the end of rehabilitation (end of phase B1), but improvement was not sustained.

Activities and Participation (d)

The FLORA and the ULV-VFQ scores are presented in Figure 4(f) and 4(g). For both, visual analysis reveals improved activities and participation during rehabilitation up to a plateau (T5), followed by a slight decrease. For FLORA (see Table 4) Mr. H’s best results (T5) were obtained with supportive instructions and in a controlled environment; for the ULV-VFQ, the participation score lays between “impossible” and “very difficult.”

Table 4.

Best results obtained by the participant on FLORA (T5).

Score category	Tasks
Easy	Visually locate people in a non-crowded settingDetermine when people walk byDetermine the direction of movement of people walking by
Reasonable	Follow a line on the floorAvoid obstacles while walkingEstimate the size of an obstacleSort light from dark laundry (socks)Locate lights in the environmentUse light from windows to determine orientationDetermine whether room lights are on or offDetect another person approaching
Difficult	Visually locate a place setting on a dining tableLocate ordinary objects at various distances (familiar environment)Find doorwaysUse artificial light to determine orientation
Impossible	Identify ordinary objects at various distancesVisually locate people in a crowded settingDetermine the direction another person is facing

Participant’s Views (e)

Mr. H reported that, at the start of rehabilitation, he used the RPS daily for 3–4 hours; at the end of rehabilitation, he was using it for 2 hours, three or four days per week. Mr. H’s perceptions about the system are presented in Table 3.

Discussion

The objective of this study was to track the functional and psychological development of an individual following the implantation of an RPS, from the selection process to long-term follow-up and including multiple interdisciplinary rehabilitation interventions.

The selection process at T0 confirmed that the participant was an appropriate candidate: He had no light perception in either of his eyes (i.e., he was totally blind) before the study, no cognitive impairment, and was emotionally stable and expressed realistic expectations about the system. Finally, he was able to manipulate the system easily. However, he had few significant functional goals. Two elements were identified that could have altered the positive prognosis for visual rehabilitation with the RPS: For the rehabilitation team, the presence of CBS; and for the surgeons, a previous “revitalizing surgery.”

Concerning sensory functions, the participant’s prosthetic visual acuity results place him in the middle range or slightly above average (Finn et al., 2018). The participant’s visual acuity improved, but he remained functionally blind (blindness category 4 according to WHO (2001)). His visual field also improved, but was limited to approximately 10 × 10 degrees, which complicated his ability to perceive an object as a whole and required extensive scanning. A mild decrease in visual functioning was measured over time. Although this decrease may be attributed to measurement error, the participant also reported a corresponding decrease is his vision from T3 to T7.

Concerning mental functions, mood issues could explain the changes in some scores at T7. Also, there appeared to be less effort, since Mr. H quickly abandoned the tasks (e.g., STM). The interventions provoked another period of grieving his loss of vision, and despite the rehabilitation team’s focus on his expectations concerning the RPS, Mr. H’s disappointment with the poor functional outcome seemed inevitable. Consistent with the literature (Finn et al., 2018; Ghodasra et al., 2016), managing user expectations remains a crucial issue, regardless of what an individual says during the selection process. Many authors (Devenyi et al., 2018; Finn et al., 2018) focus on the hope given by this kind of technology, but do not address the need for psychological support related to disappointed hopes and expectations, which highlights the importance of a holistic and transparent approach to visual devices.

Concerning neuromusculoskeletal and movement-related functions, Mr. H’s balance improved slightly for several weeks, but returned to the same point 18 months later. The improvement (T0 to T4) may be explained either by the stimulation generated by rehabilitation (walking more) or a greater effort from Mr. H (possibly induced by his will to prove he was really a good candidate or high motivation toward the RPS). The decrease of the effect at T7 also coincides with the negative mood episode reported above.

Regarding the ability to carry out activities, the RPS only allowed the participant to detect and locate targets in a simple and clear environment. Under these conditions, the participant could follow, reach, and avoid a target. One target could also be compared to another, but only if both were very simple. Nonetheless, their identification required a lot of time for analysis and deduction. It is important to note that the instructions had to be supportive. An RPS user can be confused by reflections and perceive them as actual objects. These parameters can be adjusted in the laboratory, but not necessarily in one’s home environment. Mr. H’s capacities improved (i.e., carrying out the task in a controlled environment), but there was no effect on performance (the ability to perform tasks in one’s personal environment, at home). Moreover, Mr. H pointed out that he considered the use of the RPS in a real-life travel situation more dangerous. With the RPS, he had to divide his attention, which prevented him from listening well to sounds or using his white cane. At the end of the follow-up period, he was using the RPS mainly for entertainment. In our opinion, standard rehabilitation provides results that are equivalent or superior to what this technology currently allows. In hindsight, a clinician who takes into account the level of vision provided by the RPS knows that he or she will need to put more effort into the person’s nonvisual skills to enable the person to function.

With regards to the cost-effectiveness of the Argus II RPS, despite a favorable context of interdisciplinary rehabilitation, the results were mitigated by limited cost-effectiveness. This is in line with the recent conclusion of the Institut national d’excellence en santé et en services sociaux [National Institute of Excellence in Health and Social Services] (INESSS) in Quebec, which determined that public reimbursement of the Argus II epiretinal prosthesis is not a fair and reasonable option (Arbour et al., 2019). Since the Second Sight Company went out of business in April 2020, no further Argus II surgeries will be performed, and we will not be able to replicate our results with other individuals. However, the study results could help better organize the selection and rehabilitation processes for the next generation of visual implants. If technological improvements lead to better visual performance, this could certainly increase the cost-effectiveness of such technologies.

Limitations

The findings of this study are limited by the fact that this is a single case, and the assessments were performed by clinicians providing the interventions. However, to our knowledge this is the first time that an 18-month follow-up study has been conducted on the rehabilitation of a person with an RPS, with functional and psychological data.

In addition to objective measurements (such as visual acuity), other measurements (like ULV-VFQ) may have been biased by the participant’s desire to please the evaluator or by his satisfaction with receiving services.

Comparable amounts of data in each phase of the A1-B1-A2-B2 type design would have allowed us to perform a statistical analysis (see Perdices and Tate, 2009).

Conclusion

The selection process performed by the rehabilitation team certainly is a factor worth considering, as it might facilitate interventions. However, it is not sufficient to guarantee success. Improved vision with the RPS does not automatically translate into increased participation in the living environment. New technological innovations allow for impressive advances, but sometimes make people hope for unrealistic results. Pointing this fact out to potential candidates is not always enough to make them aware of the risk, even if it is done as early as during the selection process. Psychological support is essential throughout the process. Our results suggest that, for some RP individuals, the RPS would not provide any added benefit when compared to standard rehabilitation. This study provides a detailed description of a rehabilitation process associated with prosthetic vision that could prove helpful when more advanced technologies become available.

Footnotes

Acknowledgments

The authors thank the participant, his family and friends and the other professionals who participated in the data collection working at the Institut Nazareth et Louis-Braille du CISSS de la Montérégie-Centre, and Hôpital Maisonneuve-Rosemont du CIUSSS de l’Est-de-l’Île-de-Montréal.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Frédérique Poncet

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