O Donnell Pappas syndrome

Overview

A rare eye disorder characterized by early onset of cataracts and an underdeveloped fovea which is responsible for seeing details such as is needed when reading

Symptoms

* Rapid involuntary eye movements * Presenile cataract * Mild foveal underdevelopment * Peripheral corneal pannus

Causes

* accompanied by vertigo, tinnitus, or deafness): Etiologies include labyrinthitis, vestibular neuronitis, Ménie're's disease, migraine, BPV –Central (asymmetric, rotary nystagmus that changes direction in different gazes, no latency, not fatigable): Etiologies include lesions of cerebellum, pons, or cerebellopontine angle –Horizontal * Gaze-evoked –Physiologic: Fixing on objects with eyes when head is turned (e.g., ballerinas) –Pathologic (asymmetric): Etiologies include toxic-metabolic lesions, cerebellar or pontine lesions * Dissociated (different nystagmus between eyes): Etiologies include internuclear ophthalmoplegia of multiple sclerosis or cerebral disease * Periodic alternating nystagmus (cervicomedullary junction) * Downbeat (cervicomedullary junction, characteristic of syringobulbia) * Upbeat (brainstem or cerebellum when present in primary gaze; drug effect if only present in upgaze) * Drug-induced (e.g., anticonvulsants, sedatives, alcohol) * Monocular visual loss (ipsilateral slow vertical oscillation) * Head nodding, head turn (due to motor or sensory deficits) –Latent nystagmus (occurs only when one eye is viewing, and is always associated with strabismus) –Nystagmus blockage syndrome (convergence, esotropia, and head turn) –Spasmus nutans: Onset 4–14 months, resolves by age 5; head nodding, torticollis, see-saw

Diagnosis

1. Is the nystagmus pendular? Pendular nystagmus without a fast or slow component suggests ocular nystagmus due to albinism, partial blindness, or other ocular disorders. 2. Is it intermittent or fatigable? Intermittent or fatigable nystagmus suggests otologic disorders such as acoustic neuroma, Ménière's disease, vestibular neuronitis, and acute labyrinthitis. 3. Is there associated tinnitus or deafness? The presence of nystagmus with tinnitus or deafness also suggests otologic disorders such as acoustic neuroma, Ménière's disease, or cholesteatoma. If there are long tract signs, multiple sclerosis and brain stem tumors must be considered. 4. Is the nystagmus brought on by change of position? Nystagmus brought on by certain changes of position suggests benign positional vertigo. However, this also may be found in post-traumatic labyrinthitis and postconcussion syndrome. 5. Are there associated long tract signs? The presence of long tract signs suggests multiple sclerosis, basilar artery insufficiency, syringomyelia, and Friedreich's ataxia. Certain brain stem tumors may also be associated with long tract signs.

Treatment

* Treat the underlying etiology if possible * Remove offending medications/toxins if possible * Medications to treat the nystagmus (e.g., meclizine for BPV) have varying success * BPV: Otolith repositioning maneuvers (Epley's, Semont's) * Botulinum toxin injection to the appropriate extraocular muscles may be used for severe disabling nystagmus * Congenital nystagmus: Maximize vision by refractive lenses, treat amblyopia (“lazy eye”) if indicated, prism, and/or eye muscle surgery * Vestibular: Vestibular suppressant (meclizine, diazepam), vestibular adaptation exercises * Baclofen may be useful in periodic alternating nystagmus and some congenital nystagmus * Clonazepam for downbeat nystagmus