Duanes Syndrome

DEFINITION:

Duane’s syndrome is characterized by three potential categories of disorders:

Duane’s Type I: marked limitation/absence of abduction, normal or slightly restricted adduction, globe retraction on adduction, narrowing of the palpebral fissure upon adduction, and widening of the palpebral fissure upon attempted abduction.

Duane’s Type II: marked limitation/absence of adduction, normal or slightly restricted abduction, globe retraction on abduction, narrowing of the palpebral fissure upon abduction, and widening of the palpebral fissure upon attempted adduction.

Duane’s Type III: combination of restriction or absence of abduction and adduction with globe retraction and narrowing of the palpebral fissure upon attempted adduction.

SIGNS AND SYMPTOMS:

The signs and symptoms associated with Duane’s syndrome may include, but are not limited to, the following:

1. eye turn, deviation (ICD:H51.9); sensation of monocular viewing; head turn
2. defective stereopsis and inaccurate/inconsistent depth judgment
3. general fatigue after sustained task
4. diplopia (ICD: H53.2)
5. inaccurate eye-hand coordination
6. reduced efficiency and productivity/diminished accuracy/inconsistent work product
7. asthenopia and diminished performance with increased task time
8. abnormal postural adaptation/abnormal working distance (ICD: R29.3)
9. spatial disorientation/incoordination/clumsiness (ICD: R27.8)

DIAGNOSTIC FACTORS:

Duane’s syndrome is characterized by one or more of the following findings:

1. limitation of either adduction or abduction
2. globe retraction and narrowing of the eye upon attempted adduction
3. eye is deviated inward

THERAPEUTIC MANAGEMENT CONSIDERATIONS:

The doctor of optometry determines appropriate diagnostic and therapeutic modalities, and frequency of evaluation and follow-up, based on the urgency and nature of the patient’s conditions and unique needs. Vision disorders that are not totally cured through vision therapy may still be ameliorated with significant improvement in visual function and quality of life. In cases of Duane’s syndrome, co-management with medicine (i.e. internists, neuro-ophthalmology and/or ophthalmology) is often in order due to systemic complications. The management of the case and duration of treatment would be affected by:

1. the severity of symptoms and diagnostic factors, including onset and duration of the problem
2. the complications of associated visual conditions
3. implications of patient’s general health, cognitive development, physical development, and effects of medications taken
4. etiological factors
5. extent of visual demands placed upon the individual
6. patient compliance and involvement in the prescribed therapy regimen
7. type, scope, and results of prior interventions

 

PRESCRIBED TREATMENT REGIMEN:

Some cases are successfully managed by the prescription of therapeutic lenses and/or prisms. Many Duane’s syndrome cases benefit from optometric vision therapy, which incorporates the prescription of specific treatments in order to:

1. develop adequate fusional vergence ranges and stability in all positions of gaze at distance and near
2. enhance accommodative/convergence relationships
3. enhance depth judgments and/or stereopsis
4. integrate binocular function with information processing
5. enhance fusional vergence facility and flexibility
6. integrate binocular skills with accurate motor responses
7. integrate binocular skills with other sensory skills (vestibular, kinesthetic, tactile, and auditory)
8. increase visual stamina/integrate newly established skills with information processing

DURATION OF TREATMENT:

The following treatment ranges are provided as a guide. Treatment duration will depend upon the particular patient’s condition and associated factors. When duration of treatment beyond these ranges is required, documentation of the medical necessity for additional treatment services may be warranted for third-party claims processing and review purposes.

1. Full treatment requires resolution of associated visual conditions.
2. The most commonly encountered cases of Duane’s syndrome usually require 24 to 32 hours of office therapy.
3. Associated factors such as cerebral vascular accident, head trauma, and/or systemic conditions may warrant an increase in treatment period.

FOLLOW-UP CARE:

At the conclusion of the active treatment regimen, periodic follow-up evaluation is required. Should signs, symptoms, or other diagnostic factors recur, further therapy may be medically necessary. Therapeutic lenses may be prescribed during or at the conclusion of active vision therapy to assist in the maintenance of long-term stability.