Visual rehabilitation interventions following mild TBI

In an alternate therapy study to examine the effects of hyperbaric oxygen (HBO₂) on eye tracking abnormalities after mTBI by Cifu et al. (2014), the research population were 60 male military servicemembers with at least one mild traumatic brain injury from combat, confirmed by a TBI specialist, and a mean age of 23.3. No subjects reported any active difficulty with the following vision-related items; blurred vision, light sensitivity and double vision. It was a 10-week single-center, randomized, double-blind, sham-controlled, prospective study at the Naval Medicine Operation Training Center. At each once a day session, the subject breathed either surface air, 100% oxygen at 1.5 ATA, or 100% oxygen at 2.0 ATA for the duration of 1 hour.

To determine if treatment effect existed, the study utilized computerized eye tracking equipment to examine the possible effects of hyperbaric exposure on individuals with mTBI and persistent post concussive syndrome. There were no clinically significant improvements associated with the exposure to the HBO₂ (Cifu et al., 2014).

Gallaway, Scheiman & Mitchell (2017) performed a study to determine the frequency and types of vision disorders associated with concussion related symptoms and to determine the success rate of vision therapy for these conditions in two private practice setting that specialize in vision therapy/neuro-optometric rehabilitation. A total of 95 subjects with concussion participated in the study, they had a mean age of 20.5 years, post-concussion vision problems were prevalent and convergence insufficiency and accommodative insufficiency were the most common diagnoses. Vision therapy consisted of once or twice weekly 45 minute in office sessions, for 3-5 days a week 15 minutes of home activities were completed. The vision therapy activities consisted of various vision exercises that utilized the use of optical devices such as loose lenses, prisms, polaroid glasses and computerized vision training (Sanet Vision Integrator and Computer Orthoptics Random Dot Stereogram). Clinically and statistically significant changes were seen in the areas of near point of convergence, positive fusional vergence and convergence insufficiency symptoms, accommodative amplitude and eye movement (Gallaway et al., 2017).

Thiagarajan & Ciuffreda (2014) published an article regarding oculomotor rehabilitation in mild traumatic brain injury. Both studies were a crossover, interventional experimental design of a single blind nature, eight females and four males between the ages of 23 and 33 participated in the discussed studies. In one study they evaluated accommodative parameters in mild TBI before and after oculomotor training. This was a lab-based oculomotor training and a placebo training, which consisted of 6 weeks, two sessions per week, 3 hour of training each. The oculomotor training used computerized exercises to train accommodation (with plus and minus lenses), version and vergence which was done in a clinical setting. Following the oculomotor training, the dynamics of accommodation improved significantly. After the placebo training, none of the measurements were found to have significantly changed (Thiagarajan & Ciuffreda, 2014).

Thiagarajan (2014) also published a study to determine if oculomotor training is effective in individuals with mTBI having oculomotor-based signs and symptoms following their mild traumatic brain injury. The sample size and characteristics were the same as the previous article, this was also a lab-based training program over 6 weeks. Each session was 40 minutes in duration involving 30 minutes of actual training, 15 minutes for horizontal vergence and 15 minutes for accommodation, with rest periods. The training resulted in significant improvements in those with mTBI with intersystem correlation. The researchers concluded that this suggested considerable residual neural visual system plasticity in adults with mTBI. (Thiagarajan, 2014) Clark and Bigsby (2017) published an article in which they assessed if colored glasses mitigate photophobia symptoms in individuals with posttraumatic mild brain injury. This was a cross-sectional study in a rehabilitation clinic, they assessed post-concussion patients for visual symptoms including photophobia and photosensitivity. Off the shelf glasses were used to determine if there were specific colors that provided relief, the test was done using a penlight and multiple pairs of colored glasses. A total of 39 patients had visual symptoms, 76% complained of photophobia and 85% of these patients reported relief of their symptoms while using their colored glasses. Blue, green, red and purple colored glasses provided the most relief (Clark et al., 2017)

A case report by Olson, Tunning & Boesch (2016) described the chiropractic management of a 14-year-old boy with post-concussion syndrome 13 days after his initial injury. The patient experienced occipital headache, upset stomach, blurry vision, nausea, dizziness, balance problems, a “foggy feeling”, difficulty with concentration and memory, fatigue, confusion, drowsiness and irritability. Multimodal manual therapy and chiropractic interventions were used, which included spinal manipulative therapy, myofascial release and instrument-assisted soft tissue mobilization. Additionally, the patient was given exercises to further rehabilitation, this included cervical retraction with superior ocular movement, heel-to-shin walk with the eyes open and closed and sideways crisscross stepping with the eyes open. The patients neurocognitive testing scores improved, the patient didn’t report any symptoms after the treatment plan and was found fit to play (Olson et al., 2016).

In an article on the role of the cervical spine in post-concussion syndrome by Marshall, Vernon, Leddy & Baldwin (2015) presented 5 case reports, 2 of which had visual problems that were co-managed with an optometrist. One of these cases mentioned a 19-year-old male hockey player that sustained a concussion after a car accident. He presented 14 weeks after the accident with frontal headaches, visual problems, concentration difficulties, neck pain, irritability, emotional lability and sleeping difficulties. The visual difficulties were with visual smooth pursuit demonstrating saccadic eye movements, after the initial exam, chiropractic treatment of the cervical spine was initiated. After the treatment, the patient reported significant relief of his symptoms. After the seventh visit, the patient reported residual symptoms of a neck pain as well as blurred vision. He was referred to a performance vision optometrist for co-management, he was given visual exercises and reported on the eighth visit that he was symptom-free.

The second case was of another 19-year-old hockey player that was referred by his family physician to the chiropractor, following 2 years of post-concussion symptoms resulting from a body check. Symptoms included dizziness, tinnitus, headache, mental fogginess, sleep disturbance and mild visual difficulty’s particularly with reading and watching television. For the visual difficulties he was referred to a performance vison optometrist for co-management. This optometric care was not specified in the article. His care was still ongoing during the writing of the article by the authors (Marshall et al., 2015).