Vision therapy management for dissociated horizontal deviation.

PURPOSE: Dissociated horizontal deviation (DHD), a rare subtype of strabismus, is a change in horizontal eye alignment that does not obey Hering's law. The variation is unrelated to a change in accommodation and depends on which eye is fixating. Both esotropia (ET) and exotropia (XT) can manifest in the same patient with DHD. Surgery has been reported to manage DHD, but often a second or third surgery is necessary. We report two cases of DHD that were managed with vision therapy (VT). CASE REPORTS: Case one: A 9-year-old girl presented for eye examination with her parents noting an eye drifting out. Cover test showed a DHD that varied from 15Δ left ET to 15Δ alternating XT. A 40Δ XT manifested when she was inattentive. Antisuppression, vergence, accommodation, and oculomotility were addressed with VT. Upon completion of VT, binocular vision functions were normal except for appreciation of global stereopsis. No strabismus was observed during the examination. These findings were stable at a 7-month follow-up visit. Case two: A 40-year-old man presented for eye examination with the complaint of double vision and eye strain. Cover test revealed a DHD that varied from 5Δ ET to 15Δ XT, along with DVD. A 30 to 40Δ XT was observed during visual inattention. Antisuppression and vergence skills were addressed with VT. At the end of VT, most binocular vision functions were normal. No strabismus was observed on cover test. Follow-up examination 16 years later showed no strabismus by cover test, although XT manifested when he was inattentive. CONCLUSIONS: In two DHD cases, control of eye alignment improved with VT. To the best of our knowledge, these are the first case reports to describe management of DHD with VT. Eye care practitioners should be aware that a long period of VT may be necessary to successfully manage DHD.

Diagnosing and managing functional visual complications after brain injury.

BACKGROUND: Brain injury caused by an arteriovenous malformation (AVM) hemorrhage is an uncommon occurrence in a teenager. An AVM is a congenital anomaly of unknown etiology, often described as a tangle of arteries and veins that may vary in length and width leading to a loss of capillary bed. The vessels can break down with time and cause hemorrhage or aneurysm. Hemorrhage occurs in a significant number of patients with AVM. Intracranial hemorrhage causes brain injury, which can lead to systemic and ocular complications, neurologic deficits, and death. CASE REPORT: A 15-year-old girl presented to our clinic with a chief complaint of horizontal diplopia while reading, lasting from seconds to 5 minutes. Nine months before the examination she had a ruptured cerebral AVM, then surgery to control the bleeding. She spent 6 weeks in a coma after surgery and woke up a hemiplegic. There were no visual problems before the bleeding. Our evaluation showed accommodative insufficiency, oculomotor dysfunction, dry eye syndrome, and a right beating latent nystagmus in both eyes. Perceptual testing showed a severe visual sequential memory deficit. The patient was given a reading prescription to aid with accommodation and was to use artificial tears and lacrilube ointment. At the follow-up examination, she reported increased efficiency and fewer episodes of diplopia while reading with bifocals and fewer dry eye symptoms since using the artificial tears. CONCLUSIONS: After a brain injury, a young adult can present with perceptual and visual efficiency problems as well as nystagmus. It is important to test all areas that may be affected by this type of event and to investigate all complaints thoroughly with continued follow-up care. A latent nystagmus was discovered during thorough near point testing. The visual perceptual testing helped to confirm the visual sequential memory deficit, which may otherwise have been overlooked. It is believed that the diplopic complaint and poor oculomotor skills were directly related to the newly acquired nystagmus.

An optometric approach to patients with sensory integration dysfunction.

BACKGROUND: Sensory integration dysfunction is a neurologic condition that can cause children to process environmental sensations in an inappropriate way. As a result, they may either seek out strong sensations or avoid even mild sensations. Some of the characteristics of these children may be hyperactivity, poor awareness of pain, high risk taking, listening to loud sounds, clumsiness, poor fine motor skills, poor gross motor skills, poor visual tracking, problems with sequencing, and problems with balance. Sensory integration dysfunction often is related to children with developmental disabilities, autism, and attention deficits. METHODS: Two children from the same family were examined for general eye examinations because of a history of sensory integration problems. J.H., an 11-year-old girl, and her 6-year-old half-brother, A.T., returned to the clinic for visual-perceptual testing: the Test of Variables of Attention (TOVA), the Developmental Eye Movement Test (DEM), and the Visagraph (Compevo AB, Stockholm, Sweden). The use of yoked prisms with these children was also explored. RESULTS: Both children showed oculomotility problems based on the DEM and Visagraph results. Whereas J.H. performed well on the visual-perceptual profile overall, A.T. showed problems in many areas such as reversals, visual spatial relations, visual sequential memory, visual form constancy, and attention. Both children were low hyperopes and showed positive postural and balance changes when tested with yoked prisms. CONCLUSIONS: Children with sensory integration dysfunction can have a number of signs and symptoms that may bring them to the optometrist's office. It is important to thoroughly test their visual, perceptual, and oculomotor systems to determine the best way to help these patients. The use of vision therapy and yoked prisms can be beneficial treatment options for many of these patients.