The effect of prism adaptation therapy and the practice in treatment of post-stroke unilateral spatial neglect

Abstract

Background: Unilateral Spatial Neglect (USN) affects the rehabilitation process and leads to poor functional outcomes after stroke. Knowledge and research about the rehabilitation of USN seem plentiful albeit most studies on interventions for USN treatment seem to present mixed results. Also, physiotherapists’ level of uptake of available evidence in USN rehabilitation in their practice and the barriers they encounter are not known in South Africa and Nigeria. Evidence for the treatment of USN in the sub-acute phase of recovery is not conclusive. This thesis aims to bridge the gap.

Objectives and Methodology: The purpose of this thesis is to explore the current trend of USN treatment, to evaluate physiotherapists’ knowledge, current practice, barriers and facilitators to USN rehabilitation in South African and Nigerian cohorts and to evaluate the effect of prism adaptation on USN in stroke survivors at the subacute phase of recovery.

To achieve these thesis aims, this study was conducted in stages.

Stage I: A scoping review was undertaken using a three-step search strategy guided by the Joanna Briggs Institute's (JBI) guideline for scoping reviews. Databases such as PubMed, CINAHL, The Cochrane Central Register of Controlled Trial, SCOPUS, PROSPERO, JBI, Sport Discus and Google Scholar databases were searched. The searches were limited to publications from January 1, 2008, to May 1, 2020. Critical appraisal was undertaken by two independent reviewers using a standardized critical appraisal instrument from JBI. Non-English articles were excluded, and data were extracted using a study-specific charting table. Findings were categorized and descriptively presented using tables and figures.

Stage II Study: A cross-sectional survey was conducted to evaluate physiotherapists’ knowledge of USN, and the current practice of USN management among a cohort of Nigerian physiotherapists. Convenient sampling technique was used to recruit participants registered with the medical rehabilitation and therapist board of Nigeria. A self-developed questionnaire that assessed therapist’s knowledge, current practice, barriers and facilitators were sent electronically to therapists. Descriptive statistics and inferential statistics were used to summarise the data using STATA 16.

Stage III: A cross-sectional survey was conducted to evaluate physiotherapists’ knowledge of USN, and the current practice of USN, barriers and facilitators to USN rehabilitation among South African neuro-physiotherapists. A total sampling technique was used in this study to recruit all two hundred and seventy-seven members of the neurology special interest group of the South African society of physiotherapists. A self-developed questionnaire that assessed therapist’s knowledge, current practice, barriers and facilitators were sent electronically to therapists. Descriptive statistics and inferential statistics were used to summarise the data using STATA 16.

Stage IV study: A single-blinded randomized controlled trial was conducted to evaluate the effect of Prism Adaptation Therapy (PA), as assessed by the Behavioural Inattention Test-conventional sub-test (BIT-C) and Catherine Bergego Scale (CBS). The effect of PA therapy on activities of daily living (ADL), functional mobility, balance abilities and quality of life (QoL) were evaluated with the Barthel index, modified Rivermead mobility index (MRM), Berg balance scale (BBS) and stroke specific quality of life (SSQoL) questionnaire respectively. A total of 74 USN patients who presented with USN following right-brain damage were divided into prism (n = 37) and control (n = 37) groups. The prism group used 20 diopter prism lenses for repeated aiming, five days a week, 12 days a day, and induced right optical shift every day, while the control group used neutral lenses for similar aiming training.

Results Stage I results: Out of the 3,648 articles identified, 311 full-text papers were screened, and 86 articles were critically appraised, with 83 articles included in the final review. Thirty-seven studies were quasi-experimental, and 46 studies were randomized controlled trials; most interventions targeted stroke patients at the sub-acute phase of recovery. Thirty interventions for post-stroke unilateral spatial neglect symptom amelioration were identified and studies using randomised control trial study design were in majority. Prism Adaptation (PA) was the most investigated intervention while combination therapy appeared to be a new approach.

Stage II results: Two hundred and forty physiotherapists responded to the Nigerian survey. The total knowledge score was 12.6±4.75 on a scale of twenty-five. Nineteen Physiotherapists (7.92%) demonstrated good knowledge of USN, while the majority had moderate knowledge (N=154; 64.17%). There was no significant association between USN knowledge and physiotherapist’s gender (t=0.25; p=0.801), Cadre (F=1.94; p=0.470), settlement setting of facility (F=0.26; p=0.855) and physiotherapist’s educational level (F=1.94; p=0.125). However, having a postgraduate certification in neurorehabilitation (t=-3.780; p=0.001), clinical practice setting (F=3.51; p=0.008), and working full time in neurorehabilitation (t=-2.158; p=0.033) were significantly associated with therapist’s knowledge of USN. There was also a non-significant minimal positive correlation between duration of practice in neurorehabilitation setting (r=0.02; p=0.854), with USN knowledge. Further, there was a non-significant minimal negative correlation between practice as a physiotherapist (r=-0.02; p=0.772) with USN knowledge. Age of physiotherapists showed no linear relationship with therapist’s knowledge of USN (r=-0.00; p=0.992).

Constraint-induced movement therapy (CIMT) (86.47%) was the most common used USN treatment while Albert's test (49.37%) was the most utilized screening tool for USN. When therapists were asked about enablers to USN rehabilitation “Specialized training in USN management” was reported by a majority (83.56%) of a physiotherapist as an enabler to post-stroke USN treatment; “Presence of multidisciplinary stroke team in clinical practice” (83.56%) and “Availability of relevant equipment at clinical practice” (84.25%) were also found to be major enablers. The majority of the respondents indicated that “Lack of relevant equipment for Rehabilitation of USN at clinical practice” (73.72%), “Limited staff capacity” (62.82%), and “lack of hands-on pre-requisite skills needed for post-stroke unilateral spatial neglect rehabilitation” (57.0%) were the major barriers to post-stroke USN rehabilitation.

Stage III results: Twenty-eight physiotherapists completed the South African survey. The overall knowledge score of USN was 14.11±5.23 (on a total scale of 25). Key findings include a significant moderate positive correlation between respondents' age (r=0.46; p=0.016) and years of practice as a physiotherapist (r= 0.43; p= 0.026) and knowledge of USN. Constraint-induced movement therapy and mirror therapy were the two most utilized interventions for USN management by South African physiotherapists while the comb and razor test were the most utilized assessment tools utilised in patient assessment for USN. “Lack of relevant equipment for rehabilitation of unilateral spatial neglect at clinical practice” (38.89%) were identified as major barriers to USN rehabilitation whilst enablers identified by a majority of the respondents include: “Presence of multidisciplinary stroke team in clinical practice” (83.35%), “availability of adequate staffs” (76.47%).

Study IV results: There was significantly greater improvement of BIT-C in the intervention group post treatment (P= >0.001) and decline in the CBS. Greater clinical recovery (BIT-C score >129) was observed in the intervention group (n=23; 62.16%) vs control group (n=3; 8.11%) post treatment. Similarly, significant improvement, posttreatment, was observed in ADLs (p =0.011), functional mobility (p=0.016), balance (p=>0.001), and QoL (p = 0.004). Cognitive ability (OR =1.52, CI = 1.08- 2.14, p = 0.016) was found to significantly influence recovery following PA treatment. Other socio-demographic and clinical data didn’t show statistically significant influence on recovery post treatment (p>0.05).

Conclusions: A plethora of intervention studies has been explored to ameliorate neglect symptoms post-stroke. In the treatment of USN after a stroke, no single treatment has the best advantage. Evidence for the selection of treatment at a specific phase of recovery is not conclusive as both improvements and non-improvements on neglect measures were observed across all treatment approaches without specific reference to the phase of recovery. The surveys confirmed that only a small number of physiotherapists demonstrated good knowledge of USN. Prism adaptation therapy had a very low usage in USN in both the South African and Nigeria cohorts. Nigerian Physiotherapists with postgraduate qualifications demonstrated better knowledge of USN. Findings emphasize the need for more specific rehabilitation training for post-stroke neglect rehabilitation. The randomised controlled trial in this thesis confirmed that prism adaptation therapy can significantly improve ADL, balance, QoL and functional mobility in patients with subacute stroke. Good cognitive function is needed in stroke patients to benefit from post-treatment from PA therapy regimen.