[Treatment options for nystagmus]

The goal of treatment for nystagmus is to reduce or to abolish the typical symptoms associated with nystagmus. These are (i) reduction of visual acuity (and amblyopia in infantile nystagmus), (ii) abnormal head posture (with possible secondary changes of cervical spine) and (iii) oscillopsia (often connected with vertigo and disorders of gait and orientation). Treatment strategies include pharmacological treatment, surgical therapy and optical devices. Choice of treatment depends on the type of nystagmus and its characteristics.

The following surgical procedures were successfully used as treatment of selected symptoms: (i) unilateral recess-resect surgery of the dominant eye in infantile esotropia with latent nystagmus for the relief of abnormal head posture, (ii) Kestenbaum operation of both eyes in infantile nystagmus syndrome with excentric null zone and abnormal head posture, (iii) recess-resect surgery to produce artificial exophoria in infantile nystagmus syndrome. PHARMACOLOGICAL TREATMENT: Depending on the pathophysiology of different types of nystagmus, several drugs were effective in clinical application (off-label use): (i) gabapentin (non-selective GABAergic and anti-glutamatergic effect): up to 2400 mg/d in infantile nystagmus, acquired pendular nystagmus and oculopalatal tremor, (ii) nemantine (anti-glutamatergic effect): dosage up to 40 mg/d in infantile nystagmus, also in acquired pendular nystagmus and oculopalatal tremor, (iii) baclofen (GABA-B-receptor agonist): 3 × 5-10 mg/d in periodic alternating nystagmus and in upbeat nystagmus, (iv) 4-aminopyridine (non-selective blocker of voltage-gated potassium channels): 3 × 5 mg/d or 1-2 × 10 mg Fampridin in downbeat nystagmus and upbeat nystagmus, (v) acetazolamide (carbonic anhydrase inhibitor): in hereditary episodic ataxia type 2. OPTICAL DEVICES: (i) Contact lenses are used in infantile nystagmus in order to overcome negative effects of eye glasses in abnormal head posture, lateral gaze, and higher refractive errors, (ii) spectacle prisms are useful to induce an artificial exophoria (base-out prisms) or to shift an excentric null zone (base in direction of head posture) of infantile nystagmus with abnormal head posture, (iii) low vision aids may be necessary and should be prescribed according to magnification requirements.