Optometric Vision Therapy Research Articles

George Crow, O.D., Pioneer in Optometric Vision Therapy

George Crow (1901-1978) practiced optometry in southern California. He was active in the Optometric Extension Program and contributed to concepts of optometric vision therapy. Two monographs which he co-authored and his role in the 1944 Baltimore Myopia Project are discussed.

Remediation of Visual Snow (VS) and Related Phenomena in a Neuro-Optometric Practice: A Retrospective Analysis

INTRODUCTION: Visual Snow (VS) and the Visual Snow Syndrome (VSS) represent relatively new and important medical and neuro-optometric diagnoses. While there is much information dealing with their defining characteristics and diagnosis, there is a relative paucity of information dealing with therapeutic intervention. Methods: In the present investigation, a retrospective analysis of 27 patients (ages 9-55 years, mean of 28 years) with documented VSS was performed with respect to treatment of the visual snow, palinopsia, and the newly-discovered versional oculomotor dysfunctions in a private, optometric practice setting. Patients were provided a comprehensive neurooptometric and binocular vision examination, as well as completed the VSS Symptom Survey. Treatment: they were given a selection of 5 BPI and FL-41 chromatic tints to assess using a simple clinical comparison protocol for the VS; they were provided a range of saccadic tests to remediate the common finding of palinopsia; and they were given optometric vision therapy to remediate the common, versional oculomotor problems. Results: Chromatic filters were prescribed in 24 of the 27 patients for their VS, with symptom reduction of at least 50%. Reduction of the palinopsia by 50-65% was found in all 23 patients who had palinopsia following the saccadic therapy. 23 of the 27 were given oculomotor-based vision therapy for their versional deficits (i.e., OMD), and marked symptom reduction was reported in all. Conclusion: This is the first study to demonstrate that neuro-optometric rehabilitation (NOR) provided successful remediation of the problems of VS, palinopsia, and OMD in symptomatic, clinical patients with VSS.

Clinical Management of Monofixation Syndrome due to Microtropia

BACKGROUND: Monofixation syndrome is a binocular vision disorder characterized by peripheral fusion with a central suppression of one eye due to smallangle strabismus (microtropia) or anisometropic amblyopia. Reduced stereopsis and acuity are noted in the non-fixating eye. Although often left untreated due to good cosmetic appearance, central suppression and reduced stereopsis can affect visual performance, comfort, and depth perception. CASE REPORT: EJ, a 17-year-old Caucasian female was previously treated for amblyopia of the left eye (OS) with glasses and patching since age 8 with no improvement to vision. EJ experienced the following symptoms: blurred vision at near when reading, blurred vision at far distances, eye pain and fatigue, difficulty copying from the board, difficulty seeing at night while driving, and poor depth perception. Entering uncorrected visual acuity was 20/20-2 OD and 20/50-2 OS with Snellen Letter Chart. Near uncorrected acuity was 20/20 OD and 20/200 OS with a reduced Snellen chart at 40 cm. Microtropia of 2 to 12 prism diopters of esotropia, eccentric fixation on visuoscopy, and central suppression on various tests were measured. EJ was diagnosed with monofixation syndrome, monocular esotropia of the left eye, strabismic amblyopia of the left eye, suppression of binocular vision (OS), and fusion with defective stereopsis. The patient completed 19 sessions of in-office vision therapy with the practice of home reinforcement activities between therapy sessions. Visual performance was reassessed after 10 and 19 sessions of vision training with improvements noted in acuity, accommodation, oculomotor accuracy and speed, eye alignment, fusional vergence skills, and stereopsis. CONCLUSION: Optometric vision therapy can decrease suppression, improve central fusional ability, visual acuity, accommodative accuracy, and stereopsis in a patient with monofixation syndrome.

Case Study: Treatment of Adult-onset Constant Esotropia with Lenses, Optometric Vision Therapy and Prisms

There are few documented cases, and no cases with a video journal recording a successful outcome from non-surgical treatment of adult- onset constant esotropia. Resolving diplopia caused by sudden onset esotropia is typically achieved through the application of prisms, or surgery. Surgery can resolve the diplopia and significantly reduce the strabismic angle, sometimes entirely. The application of prisms can resolve the diplopia but not alter the strabismic angle . Optometric vision therapy as a treatment, with or without the use of compensatory prisms, is rarely offered.

Enhancing Vision Therapy Through a Psychological Lens: Applications to Build a Better Method

Optometric vision therapy has been a treatment modality in place to correct and treat visual dysfunction for over 90 years. Despite the abun- dant support from patients who have bene- fited from treatment, there is disagreement in the medical community about its efficacy. To dispel this notion and provide the best patient- centered care, this paper regards research from developmental psychology and learning and behavior psychology to suggest avenues that will support comprehensive therapist training and improve patient outcomes. Methods to increase patient motivation, interact with patients more effectively, build autonomy in middle childhood patients, and improve retention of visual skills are suggested to enhance therapy training programs. By improving treatment success rates and providing lasting results, this modality will find increased support through the patients and families it is serving. Ongoing research to support the efficacy of vision therapy is welcome. Investigations into special needs populations, brain injury populations, personality types, cultural, and gender differences can give insight into therapist-patient interactions and could prove beneficial in training therapists as well.

Which Comes First in Sports Vision Training: The Software or the Hardware Update? Utility of Electrophysiological Measures in Monitoring Specialized Visual Training in Youth Athletes.

In the present study we combined popular methods of sports vision training (SVT) with traditional oculomotor protocols of Optometric Vision Therapy (OVT) and electrophysiological indexes of EEG and VEP activity to monitor training progress and changes in performance of youth ice hockey players without the history of concussion. We hypothesized that administration of OVT protocols before SVT training may result in larger performance improvements compared to the reverse order due to the initial strengthening of visual hardware capable of handling greater demands during training of visuomotor integration and information processing skills (visual software). In a cross-over design 53 youth ice hockey players (ages 13–18) were randomly assigned to one of the two training groups. Group one (hardware-software group) completed 5 weeks of oculomotor training first followed by 5 weeks of software training. For group 2 (software-hardware) the order of procedures were reversed. After 10 weeks of training both groups significantly improved their performance on all but one measure of the Nike/Senaptec Sensory station measures. Additionally, the software-hardware training order resulted in significantly lower frontal theta-to-gamma amplitude ratios on the Nike/Senaptec test of Near-Far Quickness as well as in faster P100 latencies. Both training orders also resulted in significant decreases in post-treatment P100 amplitude to transient VEP stimuli as well as decreased theta-gamma ratios for perception span, Go/No-Go and Hand Reaction time. The observed changes in the electrophysiological indexes in the present study are thought to reflect greater efficiency in visual information processing and cognitive resource allocation following 10 weeks of visual training. There is also some evidence of the greater effectiveness of the software-hardware training order possibly due to the improved preparedness of the oculomotor system in the youth athletes for administration of targeted protocols of the Optometric Vision Therapy.

Introducing The Dizziness Wheel – A New Approach for Optometrists to Evaluate Dizziness/Imbalance in mTBI/Concussion Patients

More than 3.8 million Americans sustain a concussion or mild traumatic brain injury each year. Over 70 percent (2.66 million) of these patients suffer consequential vision dysfunctions. Research has shown that optometric vision therapy can provide significant improvement in post-concussion vision problems. However, assessing and managing post-concussion visual dysfunctions can be challenging for the optometrist. This difficulty is primarily due to the complex and diffuse damage the brain incurs from concussion, resulting in a unique clinical profile for each individual patient. When vision-based dizziness or imbalance complaints are included in the post-concussion patient’s presentation, the evaluation and management process becomes more complicated. This challenge is exacerbated by the plethora of comorbid, non-vision-based causes for dizziness/imbalance (D/I) that might also be present. According to the Center of Disease Control and Prevention, more than one-third of adults aged 65 years and older suffer falls each year, many of which are secondary to D/I. At least half of the U.S. population is affected by a balance or vestibular disorder sometime during their lives. The purpose of this article is to introduce The Dizziness Wheel. It is a graphic tool, developed and utilized by this author, to help assess and triage a concussed patient’s D/I. It also aids the identification of links amongst multisystem disruptions. This is especially helpful because D/I almost always represent a complex combination of overlapping symptoms. The Dizziness Wheel is not intended to be used as a formal diagnostic tool. Rather it is a differentiation graphic for use throughout the patient’s therapeutic experience. This author has found it to be helpful during initial exams, follow-ups, and in-office therapy. The Dizziness Wheel also can serve as a helpful guide for referral to other types of healthcare providers. Many D/I patients present to the neuro-rehabilitation optometrist without having been comprehensively assessed and treated for non-visual causes of D/I. The Dizziness Wheel can help the optometrist ensure the patient’s safety and access to effective integrated management of dizziness and imbalance.

A Team Approach to Remote Vision Therapy and the Transformation to Virtual Vision Therapy

Our practice, Alderwood Vision Therapy Center (AVTC) focuses on optometric vision therapy. We are located in Washington state. This holds great significance in this era of COVID-19 as the first documented case of the novel coronavirus in the United States was confirmed in Washington State on January 21, 2020. The individual who holds this ominous distinction, a gentleman in his 30s, had travelled to Wuhan, China where the pandemic originated. Initially there was optimism that our practice could continue in-office operations at our two locations. We sent out a notice to our patients that we were making continual changes to our normal practices in response to the COVID-19 outbreak. These changes included having only those individuals essential to the patient’s visit attend the appointment as to limit exposure in the reception area. Patients were advised that if they had fever within the past two weeks or had exposure to anyone confirmed as having the virus, their appointment would be rescheduled. We indicated that we were looking at the option of Remote Vision Therapy sessions and that, while insurance did not as yet pay for this, it was a vital option. It seemed as if every day the landscape was changing and it became apparent, fairly rapidly, that in-office therapy would be difficult to continue. As we investigated the alternative of Remote Vision Therapy more seriously, we ultimately made the heart wrenching decision to close in-office operations on March 18, 2020, five days in advance of Governor Jay Inslee’s Stay Home Order that closed nonessential businesses in the state.

Use of Remote Optometric Vision Therapy in a Primary Eye Care Practice

Many optometrists supplement office-based vision therapy with home-based vision therapy procedures. Others prescribe primarily home-based vision therapy activities with in-office instruction. With recent development of telehealth online platforms, it is possible to enhance home-based vision therapy with one-on-one doctor-guided and vision therapist-guided remote optometric vision therapy (ROVT). This may increase access for times when the patient is not able to present to the office. Procedures for implementing ROVT are discussed including patient selection, case management, and technical requirements. 35 patients received ROVT, with the vast majority responding positively. Three cases of ROVT are presented. While there are significant limitations to ROVT, this experience shows that it is possible to conduct ROVT when there is need. We found that case selection and parental support at home are important factors for success.

Perceived Importance of and Equipment Used for Home Vision Therapy Activities

Home vision therapy activities can be prescribed as part of an in-office optometric vision therapy treatment program. Home training between in-office sessions can be prescribed anywhere from intensive activities to sporadic assignments during a week. Anteo and Emergent ran independent surveys, prior to their partnership and previous to the COVID-19 lockdown, to gather information from vision therapy providers in 2019 and 2015 respectively. Emergent is a vision therapy equipment company whose services also include online vision therapy training and practice management consulting. Anteo is a vision therapy platform for in-office and remote vision therapy. The Anteo survey aimed to (1) identify the perceived importance of vision therapy home activities during a weekly in-office vision therapy regimen (2) assess home activity compliance. The Emergent survey aimed to (1) determine what equipment providers were using when assigning home vision therapy (2) the cost and price charged for that equipment.

Management of Accommodative Insufficiency with Optometric Vision Therapy: A Case Report

Management of Accommodative Insufficiency with Optometric Vision Therapy: A Case Report

A Case of Accommodative Insufficiency with Vergence Disorder in a 17-Year Old Student

Accommodation Insufficiency (AI) is a condition in which a patient has an inability to focus or maintain focus at near. AI is mostly observed to occur with a vergence problem especially convergence insufficiency due to the close link between accommodation and convergence system of the eyes. Common symptoms seen in AI are diplopia, asthenopia and difficulty reading at near. Several management options are available including plus lenses for near work, optometric vision therapy and monitoring. A 17-year-old lady presented to the eye department with eyestrains, frontal headache, blurry vision at near with reading difficulties. According her, this problem started in 2018. Visual acuity (VA) for both distance and near was measured. Detailed anterior and posterior segments assessment revealed no anomalies, but binocular assessment showed reduced Amplitude of Accommodation (AOA), increased lag of accommodation, reduced Monocular Accommodative Facility (MAF) and Binocular Accommodative Facility (BAF), reduced Positive Relative Accommodation (PRA) and receded Near Point of Convergence (NPC). Based on the patient’s complaint and what the assessment revealed, accommodative insufficiency with vergence disorder was made. Vision therapy and distance optical correction were prescribed to manage the problem. Accommodative Insufficiency can be treated effectively by an in-office/home-based program. The repetition of appropriate optometric vision therapy procedures at home will help resolve a patient’s maladaptive visual condition over time.

Incorporating Behavior Modifications, Strategies, and Supports to Maximize the Effectiveness of Vision Therapy in the Autism Spectrum Disorder Population

The prevalence of autism spectrum disorders has increased almost two-fold since 2007. This increase has facilitated a need for a new approach in vision therapy when treating deficits in accommodation, binocularity, oculomotor, and visual processing in children with autism. The clinician may face challenges when treating this population because children with autism may have difficulty engaging in reciprocal conversation, have poor attention due to sensory overstimulation, be resistant to change, or be non-verbal. This paper seeks to compile effective behavior modifications, strategies, and supports used by other professionals, such as teachers, and physical, occupational, and behavioral therapists, that may be incorporated into optometric vision therapy to maximize visual outcomes for this patient population.

ACC Research Agenda Conference 2019: Peer Reviewer Acknowledgments and Abstracts of Proceedings.

ACC Research Agenda Conference 2019: Peer Reviewer Acknowledgments and Abstracts of Proceedings.

Efektywność optometrycznej terapii wzroku w akomodacyjnej ezotropii z wysokim AC/A

Convergence excess esotropia is commonly treated with corrective glasses (plus lenses), which reduces the angle of deviation for a distance, but the near deviation is still observed. Two types of approach are used to manage convergence excess esotropia: bifocals or eye muscles surgery. Nevertheless, both treatments seem to fail to influence the stereovision. The paper describes the case of 10-year-old girl, diagnosed with convergence excess esotropia with high AC/A ratio, who was subjected to the optometric vision therapy and bifocals. As an effect, visual parameters were improved, and majority of visual symptoms decreased. This case indicates that treatment plan for esotropia should include improvement of accommodation, eye movements and inter-ocular suppression, what strongly influence oculo-motor control and stereovision.

The Role of Suppression in Amblyopia: A Literature Review

Amblyopia is a developmental vision disorder typically treated by occlusion therapy. Recent research suggests suppression is closely linked to deficits in visual acuity and stereopsis, and considerations regarding treatment should include reducing interocular suppression. The aim of this literature review is to provide an analysis of vision science research published within the past 5 years which investigates the role of suppression in amblyopia and discuss the implications to clinical practice. Recent research suggests binocular cells are present in the visual cortex of amblyopes, but are rendered functionally monocular by the development of a GABA inhibitory network. Suppression, or inhibition, can be quantified in both strabismic and anisometropic amblyopia by reducing contrast to the fixating eye until simultaneous perception occurs. In both strabismic and anisometropic amblyopes, higher levels of suppression are associated with lower visual acuities and absent stereopsis. In addition, the evaluation and treatment of suppression is important for the effective treatment of amblyopia, particularly in patients with deep suppression, as they may not respond as well to occlusion therapy. Variable contrast anti-suppression training improves visual acuity, reduces suppression, and improves stereopsis in both children and adults. No age trends were found, which suggests that significant neuroplasticity exists in the adult brain, and suppression may not need to be treated differently in children and adults. Incorporating variable contrast into anti-suppression therapy techniques may enhance treatment progress and promote the development of stereopsis. Existing optometric vision therapy techniques already used to treat suppression are described. Additionally, some of the computer-based tools possess variable contrast stimuli presentation capabilities. Further research is needed to evaluate the optimal length of treatment and long term stability of gains in visual acuity and stereopsis using this treatment strategy.

Optometric Vision Therapy for Visual Deficits and Dysfunctions: A Suggested Model for Evidence-Based Practice

Evidence from neural science supports a neuroplasticity thesis where the development and rehabilitation of functional neural pathways can be facilitated by management of biological factors, central processing and environmental interactions. Healthy eyes and clear sight are not themselves sufficient for efficient functional vision. How a person uses vision determines their operational skill. Efficient functional vision requires dynamic interactions between and within visual receptive and reflexive biology, acquired neural networks that serve basic visual inspection processes and visuo-cognitive operational patterns driving top down visual – spatial analysis and problem solving. This presentation is a review and discussion of evidence-based practice (EBP) principles that we utilise in clinical neuro-developmental and rehabilitative optometric vision therapy (OVT) for selected visual deficits and dysfunctions. OVT services, like other collaborative therapies such as cognitive behavioural therapy, speech therapy and occupational therapy, must progressively adapt to new knowledge and advancing technology through EBP. Clinical services directed at treatable neuro-developmental and acquired dynamic functional vision problems require the application of an emerging set of principles resulting from systematic logic and EBP related to the art and science of case analysis, practice management and OVT delivery.

Vision therapy for basic exotropia in adults: 2 case studies

Background Basic exotropia accounts for approximately 50% of all intermittent exotropias. Many clinicians view treating these patients, especially adults with childhood-onset exotropia, as challenging. Conflicting opinions still exist regarding prescribing any treatment for adult strabismics, including surgical realignment and optometric vision therapy (VT). Case Reports Two cases are discussed, both of which are adult patients with moderate-size intermittent exotropia of the basic type who presented with asthenopia, headaches, and/or diplopia. Twenty to 30 in-office VT sessions were recommended to reduce the magnitude and frequency of the deviation as well as improve their binocularity and decrease their symptoms. After completing VT, both patients became phoric for all distances, had normal vergence ability, and had normal near points of convergence. In the second case, the long-term outcome was evaluated 5 years post-therapy. Conclusion Optometric VT was highly successful in both patients with childhood intermittent exotropia of the basic type. Most important, optometric VT eliminated the patients’ symptoms of asthenopia and diplopia without the need for surgery.

Vision Therapy and Orthoptics

Vision therapy by orthoptists is a form of treatment to restore binocular single vision and to enhance the control of a deviation using prisms and convergence therapy. It is differentiated from optometric behavioral vision therapy (BVT) as a form of treatment to decrease rates of juvenile recidivism and to improve learning disabilities using colored overlays and tools such as trampolines. Evidence-based findings of randomized controlled clinical trials versus conclusions drawn from nonrandomized, poorly controlled studies of various forms of vision therapy are explored. Concrete evidence in the mainstream literature supports the positive effects of eye exercises in patients with convergence insufficiency and yoked prisms in patients with neurologic deficits. Vision therapy for juvenile delinquents and patients with dyslexia is unsubstantiated.

The College of Optometrists in Vision Development checklist related to vision function: Expert opinions

Background The College of Optometrists in Vision Development (COVD) Quality of Life (QOL) checklist has been reported to have good test-retest reliability. Symptom scores measured by this instrument have demonstrated validity by showing a significantly improved score with optometric vision therapy. The COVD-QOL scores inversely correlate with academic achievement on standardized tests, and the instrument has been shown to differentiate between attention deficit disorder/attention deficit hyperactivity disorder children. The individual items on the COVD-QOL have not, however, been studied as to their relationship to general areas of vision investigated by the optometric examination. Methods To ascertain if COVD-QOL symptoms can be related to areas of vision function, a group of 28 practicing optometrists from all parts of the United States were surveyed for their opinions. The venue was a conference whose theme was vision therapy and the functional use of lenses and prisms. All the participants offered vision therapy within their practices. They were asked to rank 5 general areas of vision skills (orientation, ocular motor, binocular, accommodation, and perception) as to whether these areas might relate to individual symptoms contained in the COVD-QOL. A frequency distribution was developed based on these results. A Likert scale was also used to compare the specific symptom (COVD-QOL item) to the opinion of the clinicians who participated. A Likert scale assumes equal separation among the 5 levels of symptom severity. Results Thirteen items were found to have high agreement, and 11 were considered in moderate agreement when the opinions of these experts were compared. Each of the 5 areas of vision had at least 1 item with high or moderate agreement. Conclusions Expert opinion is a reasonable first step in investigating symptoms as they relate to signs, but more study is needed to verify if these subjective relationships actually exist.