Faculty Bibliography

BACKGROUND: The purpose of this retrospective study was to determine the frequency of occurrence of visual field defects in a sample of visually symptomatic, ambulatory outpatients who have acquired brain injury (ABI), either traumatic brain injury (TBI) or cerebral vascular accident (CVA). METHODS: The medical records of 220 individuals with TBI (n=160) or CVA (n=60) were reviewed retrospectively. This was determined by a computer-based query spanning the years 2000 through 2003. The individuals' records were reviewed to determine the frequency of targeted visual field defects that were classified as scattered, restricted, homonymous, nonhomonymous, and visual neglect. The altitudinal and lateral characteristics of these defects were also determined. RESULTS: In the total ABI sample of 220, some 102 (46.36%) individuals had 1 of the targeted defects diagnosed. These defects were present in 62 (38.75%) of the TBI subgroup and in 40 (66.67%) of the CVA subgroup. The most frequent defects in the TBI group were scattered (58.06%) followed by homonymous (22.58%). In the CVA group, the most numerous were homonymous (47.5%), with scattered and nonhomonymous accounting for 20% each. CONCLUSION: The uniqueness of the current study is that it reports the frequency of occurrence of specified visual field defects in the total ABI sample and in the TBI and CVA subgroups. This enabled comparisons with other studies that generally have reported on just 1 of these groupings. The current results are in accord with most of the other studies that are reviewed. The findings of this study should alert the reader to the high frequency of occurrence of visual field defects in the ABI population, and make the reader aware of the adverse effects they can have on quality of life and rehabilitation.

BACKGROUND: The purposes of this study were to retrospectively evaluate the frequency of medications used by individuals with either traumatic brain injury (TBI) or cerebrovascular accident (CVA) and to consider the possible relationship between vision symptoms and diagnoses in this sample and the established visual and ocular side effects of the prescribed medications. METHODS: Charts of patients examined in the Raymond J. Greenwald Rehabilitation Center at the SUNY State College of Optometry from the years 2000 to 2003 were reviewed. Only TBI (n=160) or CVA (n=60) patients were included. Prescribed medications from 12 possible categories were identified. Patients experiencing blurred vision, diplopia, asthenopia, poor depth perception, and/or light sensitivity were identified. Patients with accommodative dysfunction, vergence dysfunction, versional dysfunction, dry eyes, and/or ptosis were also identified. RESULTS: The 4 most common medication categories taken by TBI patients were anti-anxiety/antidepressants (42.5%), anticonvulsants (26.9%), opiate/combination analgesics (23.8%), and cardiac/antihypertensives (23.1%). For the CVA patients, the medications were cardiac/antihypertensives (66.7%), anti-anxiety/antidepressants (31.7%), vitamins/mineral supplements (26.7%), and anticonvulsants (23.3%). Frequency of vision symptoms and diagnoses in the TBI and CVA patients appeared not to be related to medication use in most cases. CONCLUSIONS: Anti-anxiety drugs, antidepressants, and anticonvulsants were the overlapping medication categories between the TBI and CVA groups. Medication intake did not affect the frequency of the reported vision symptoms and diagnoses in most cases, suggesting the symptoms and diagnoses were primarily related to either the TBI or CVA itself.

BACKGROUND: Oculomotor dysfunctions are among the most common abnormalities found in the brain-injured population. The purpose of the current study was to determine retrospectively the effectiveness of conventional optometric vision therapy for oculomotor disorders of vergence and version in a sample of ambulatory, visually symptomatic, predominantly adult outpatients who had either mild traumatic brain injury (TBI) or cerebrovascular accident (CVA). METHODS: A computer-based query for acquired brain injury patients examined between the years of 2000 and 2003 was conducted in our clinic. This yielded 160 individuals with mild TBI and 60 with CVA. Of these patients, only those for whom vision therapy was prescribed and who completed an optometric vision therapy program for remediation of their oculomotor dysfunctions were selected. This included 33 with TBI and 7 with CVA. The criterion for treatment success was denoted by marked/total improvement in at least 1 primary symptom and at least 1 primary sign. RESULTS: Ninety percent of those with TBI and 100% of those with CVA were deemed to have treatment success. These improvements remained stable at retesting 2 to 3 months later. CONCLUSION: Nearly all patients in the current clinic sample exhibited either complete or marked reduction in their oculomotor-based symptoms and improvement in related clinical signs, with maintenance of the symptom reduction and sign improvements at the 2- to 3-month follow-up. These findings show the efficacy of optometric vision therapy for a range of oculomotor abnormalities in the primarily adult, mild brain-injured population. Furthermore, it shows considerable residual neural plasticity despite the presence of documented brain injury.

PRIMARY OBJECTIVE: To determine whether critical flicker frequency (CFF) thresholds are abnormal in individuals with mild traumatic brain injury (TBI) and, if so, if they are correlated with the degree of reported motion and light sensitivity. METHODS AND PROCEDURES: The foveal CFF threshold was assessed in individuals with mild TBI (n = 18) having varying degrees of reported light and motion sensitivity. Mean CFF values were obtained using the ascending and descending psychophysical method of limits with binocular viewing at 40 cm. A 7-item, rating-scale questionnaire was used to assess the degree of light and motion sensitivity. These parameters were also assessed in a large visually-normal, non-TBI cohort. MAIN OUTCOMES AND RESULTS: CFF in the mild TBI group was not significantly different across age groups from the visually-normal, non-TBI cohort. However, mean CFF among the mild TBI subjects was significantly higher for the 'light sensitive' and 'motion sensitive' sub-groups when compared to the 'not light sensitive' and 'not motion sensitive' sub-groups. The majority of TBI subjects manifested both light and motion sensitivity. CONCLUSION: CFF was found to be related to the reported degree of light and motion sensitivity in individuals with mild TBI. Neurological disinhibition as a result of brain injury may be causal of the subjective hypersensitivity to light and motion in the presence of normal CFF.

BACKGROUND: The purpose of this retrospective study was to determine the frequency of occurrence of oculomotor dysfunctions in a sample of ambulatory outpatients who have acquired brain injury (ABI), either traumatic brain injury (TBI) or cerebrovascular accident (CVA), with associated vision symptoms. METHODS: Medical records of 220 individuals with either TBI (n = 160) or CVA (n = 60) were reviewed retrospectively. This was determined by a computer-based query spanning the years 2000 through 2003, for the frequency of occurrence of oculomotor dysfunctions including accommodation, version, vergence, strabismus, and cranial nerve (CN) palsy. RESULTS: The majority of individuals with either TBI (90%) or CVA (86.7%) manifested an oculomotor dysfunction. Accommodative and vergence deficits were most common in the TBI subgroup, whereas strabismus and CN palsy were most common in the CVA subgroup. The frequency of occurrence of versional deficits was similar in each diagnostic subgroup. CONCLUSION: These new findings should alert the clinician to the higher frequency of occurrence of oculomotor dysfunctions in these populations and the associated therapeutic, rehabilitative, and quality-of-life implications.

PRIMARY OBJECTIVE: To determine retrospectively the relative risk of ocular disease in a selected, visually-symptomatic sample of clinic patients having traumatic brain injury (TBI; n=160) vs. cerebrovascular accident (CVA; n=60), with all initially presenting at the clinic with symptoms and/or signs of vision dysfunction. METHODS AND PROCEDURES: To review retrospectively 220 medical records of individuals with TBI (n=160) vs. CVA (n=60), as determined by a computer-based query spanning the years 2000-2003, to ascertain the frequency of occurrence of ocular disease in the two major sub-groups of acquired brain injury. MAIN OUTCOMES AND RESULTS: Conditions with high relative risk unique to TBI included corneal abrasion, blepharitis, chalazion/hordeolum, dry eye, traumatic cataract, vitreal prolapse and optic atrophy. This is distinct from those ophthalmic conditions unique to CVA, which included sub-conjunctival haemorrhage and ptosis. CONCLUSION: These new findings should alert clinicians to the potential increased frequency of occurrence of specific ocular diseases in a selected, visually-symptomatic population with TBI and their associated rehabilitative and quality-of-life implications.

The purpose of this study was to assess reading-related oculomotor rehabilitation in individuals with acquired brain injury. Adults with either stroke (n=5) or traumatic brain injury (n=9) participated. Training paradigms included single-line and multiple-line simulated reading, as well as basic versional tracking (fixation, saccade, and pursuit), twice per week over an 8 week period. Training modes included normal internal oculomotor visual feedback either in isolation (4 weeks) or concurrent with external oculomotor auditory feedback (4 weeks). Training effects were assessed objectively using infrared eye movement recording technology for simulated and actual reading, with the assessments occurring before, midway, and after training. In addition, the individuals were assessed subjectively using a reading rating-scale questionnaire. All reported considerably improved reading ability, and this was confirmed by several of the objective oculomotor measures. There was a trend for improvement to be better with the combined visual and auditory oculomotor feedback. Reading-related oculomotor rehabilitation produced significant gains in both the subjective and objective domains. It is believed that rapid saccadic oculomotor adaptation, as well as the training of rhythmicity and automaticity, were involved in modifying eye movement behavior to produce a more systematic approach and resultant improved reading profile.

Many individuals with acquired brain injury (ABI) report reading problems of oculomotor origin. These may include frequent loss of place, skipping of lines and difficulty shifting to the next line of print. We describe two protocols for the testing and training of reading-related eye movements in adult individuals with ABI (traumatic brain injury [TBI] and stroke with hemianopia), who experience oculomotor-based symptoms when reading. These protocols use objective eye movement recording techniques and computer-based stimulus presentation and analysis. One protocol tests and the other trains basic horizontal and vertical versional eye movements (fixation, saccades and pursuit), as well as reading eye movements using simulated single and multiple line dynamic arrays. In addition, a reading rating-scale questionnaire is administered before and after completion of training to assess subjective reading improvement. In all paradigms, the target consists of a 0.5 degrees luminous square, which is displayed on a computer monitor positioned 40 cm from the subject along the midline. All testing and training are conducted under binocular viewing conditions with optical correction in place. There are two modes of training: normal internal oculomotor visual feedback either alone (4 weeks) or in conjunction with external oculomotor auditory feedback (4 weeks) administered in a counterbalanced manner within each diagnostic group. Training is performed 1 h, twice weekly for the 8 weeks. Oculomotor testing is conducted before, midway and after training. Following training, reading-related eye movements and reading ability improved as assessed both subjectively and objectively. These protocols provide a systematic approach to the quantitative and comprehensive testing and training of reading-related eye movement skills and behaviors in the ABI population manifesting oculomotor-based reading dysfunctions. Furthermore, the training protocol results in the rapid remediation of the eye movement deficits, which appear to transfer to activities of daily living.

OBJECTIVE: To investigate the effects of systematic, oculomotor rehabilitation on basic versional ocular motility, as well as reading eye movements, in subjects with acquired brain injury, using objective eye movement recording and subjective rating of reading ability. DESIGN: Case series. SETTING: Clinical research laboratory. PARTICIPANTS: Two men with acquired brain injury: one with traumatic brain injury and one with stroke. INTERVENTIONS: Versional oculomotor training was performed for 1 hour, twice weekly for 8 weeks. There were 2 feedback modes of training: normal internal oculomotor visual feedback alone (4wk), or that feedback in conjunction with external oculomotor auditory feedback (4wk). Testing was conducted before and after training. Main outcome measures Objective outcome measures included both basic eye movement parameters (fixational accuracy, saccadic gain and latency, pursuit gain, mean saccade frequency ratio for simulated reading), and reading eye movement parameters (words per minute, grade level equivalent, fixations per 100 words, regressions per 100 words, percentage of reading comprehension, duration of fixation in seconds). Subjective outcome measures included the subject's ability to read based on the responses to the reading rating-scale questionnaire. RESULTS: Both subjects improved objectively in terms of basic versional oculomotor accuracy and reading ability. These findings concurred with their subjective impressions. CONCLUSIONS: This case series provides objective documentation of the positive effects of oculomotor rehabilitation on basic ocular motility and reading ability in selected cases with acquired brain injury, thus suggesting the need for a larger clinical trial in this area.

Vision disturbances following traumatic brain injury (TBI) include anomalies of accommodation, version, vergence (nonstrabismic, as well as strabismic), photosensitivity, visual field integrity, and ocular health. Traumatic brain injury patients with complex diplopia patterns, noncomitant strabismic anomalies, and advanced ocular health anomalies are either monitored by or referred to neuro-ophthalmologists and ophthalmologists for evaluation and possible surgical or medical intervention, as needed. Anomalies of accommodation, vergence, version, photosensitivity, and field of vision are amenable to noninvasive, rehabilitative interventions, such as vision therapy, which is rendered by optometrists and is described in this article. Further, vision therapy may be performed in isolation or in conjunction with the application of the following: Fusional prism spectacles (for diplopia) Tinted spectacles (for photosensitivity) Yoked prism spectacles (for visual-spatial hemispheric inattention, with or without a manifest visual field defect), as appropriate Dependent on the severity of vision impairment post-TBI, other types of rehabilitation, such as vestibular, physical, cognitive, and occupational rehabilitation, are deferred pending the stabilization of vision function to an appropriate level. Rehabilitative optometric intervention is appropriate and beneficial for many TBI patients. Therefore, it should be offered as a possible evaluation and treatment option to investigate the patient's symptoms and determine the prognosis for treatment, as would be done with any other therapeutic modality.