Filter Interventions to Support Occupational Performance for People With Traumatic Brain Injury With Visual Symptoms (June 2013–October 2020)

Abstract

Systematic Review Briefs provide a summary of the findings from systematic reviews developed in conjunction with the American Occupational Therapy Association’s Evidence-Based Practice Program. Each Systematic Review Brief summarizes the evidence on a theme related to a systematic review topic. This Systematic Review Brief presents findings from the systematic review on the effectiveness of filter interventions that address visual impairments and visual perception to improve occupational performance for adults with traumatic brain injury.

Full Systematic Review Question

This systematic review addressed the question “What is the evidence for the effectiveness of interventions that address visual impairments and visual perception to improve occupational performance for people with TBI?”

Current Theme Reported

The main theme of the studies included in this systematic review brief are interventions that use filters.

Clinical Scenario

Traumatic brain injury (TBI) can have a significant impact on the visual system leading to deficits in visual field, visual acuity, oculomotor skills, and visual processing abilities (Cockerham et al., 2009), with estimates as high as 90% of all people with TBI experiencing visual consequences (Jacobson & Marcus, 2011). Visual and visual perceptual deficits as a result of TBI can significantly impact participation in meaningful everyday activities (Greenwald et al., 2012; Kerkhoff, 2000). More specifically, sensitivity to light after TBI has a significant impact on quality of life (Shepherd et al., 2019). Filters refer to colored lenses that modify the wavelength frequency, spectral composition, and overall luminance of light entering the eyes (Fimreite et al., 2016).

Summary of Key Findings

Two intervention studies that used filters during intervention were included in this review (Table 1). The levels of evidence used in this review are from Oxford Centre for Evidence-Based Medicine (2009).

Table 1.

Evidence Table for Filter Interventions

Author/Level of Evidence	Intervention	Statistically Significant Improvement Resulting From Intervention
One Level 2B randomized controlled pilot study and one level 3B retrospective cross-sectional study used filters to improve visual symptoms or reading performance. Low strength of evidence supports the effectiveness of this therapy.
Fimreite et al. (2016) 2B—RCT Setting USA laboratory clinic Country USA	Population Adults with concussion mTBI, >6 mo postinjury, N = 12 Intervention Reading tasks using colored lenses, including red, blue, neutral density BPC filters, or PT lens, as well as NL. Reading rate and oculomotor measures were assessed. Delivery Method Individual Dose Single session	Statistical significance of results were not reported.
Clark et al. (2017) 3B—Retrospective chart review cross-sectional study Setting Outpatient rehabilitation clinic Country USA	Population Adults with visual disturbances and concussion symptoms, N = 39 (33 with photophobia) Intervention A photophobia assessment was performed initially without glasses and was then followed by a photophobia assessment with glasses including a range of colored lenses. Participants then performed a range of customized activities including functional mobility in a well-lit room, looking at electronic media, reading from a book or ADL tasks while wearing colored lenses that provided relief of photophobia symptoms. Delivery Method Individual Dose Single session	Statistical significance of results were not reported. 85% of participants reporting photophobia had relief of some symptoms when using glasses of 1 or more colors. Colors that produced most relief (in order of benefit) were blue, green, red, and purple (yellow was not beneficial).

The levels of evidence used in this review are from Oxford Centre for Evidence-Based Medicine (2009). Note. ADL = activities of daily living; BPC = band-pass chromatic; mTBI = mild traumatic brain injury; NL= no lens; PT = precision tint; RCT = randomized clinical trial.

Bottom Line for Occupational Therapy Practice

Of the studies reviewed, there is low strength of evidence to support the use of filters as a preparatory strategy to improve visual discomfort and reduce photophobia in people with visual impairments post TBI (Clark et al., 2017; Fimreite et al., 2016). The use of colored filters may facilitate engagement in occupations such as reading and activities of daily living by reducing the impact of visual symptoms (i.e., visual discomfort/photophobia) on occupational performance. Occupational therapy practitioners should consult on a case-by-case basis with neuro-optometry/ophthalmology to consider the use of filters to manage/resolve visual symptoms in adults with TBI. Findings suggest that the specific color and wavelength frequency of the filter that produces the most relief will differ by individual. To promote safe participation in daily tasks, the intensity (wavelength frequency, spectral composition, and overall luminance of light) and duration of filter use should be considered in collaboration with the consulting neuro-optometry/ophthalmology. Although there is evidence to support the use of filters, it is important to keep in mind that there were only two studies that met the inclusion criteria: One was conducted retrospectively with no visually normal comparison group, and the other was a pilot study with a small sample size (n = 12).