Zusammenfassung
Nystagmus ist definiert als unwillkürliche, periodische Bewegung, bei der eines oder
beide Augen vom Fixationspunkt wegdriften (sog. Drift). Auf die Drift, die langsame
Phase, folgt
entweder eine schnelle, refixierende Bewegung (sog. Refixationssakkade oder schnelle
Phase) oder eine langsamere Bewegung zur Wiederaufnahme der Fixation. In dieser Übersichtsarbeit
sollen
die wichtigsten Formen von Nystagmus bei Kindern erörtert werden, für eine Übersicht
bei Erwachsenen sei auf [1] verwiesen.
Abstract
Nystagmus describes an involuntary, periodic movement of one or both eyes. About 1/600
children and adolescents have nystagmus, most of them idiopathic infantile nystagmus
(IIN), also
called “congenital nystagmus”, which can be caused by mutations in the FRMD7 gene. Other frequent forms of nystagmus are latent nystagmus, which is usually associated
with infantile
strabismus, and nystagmus associated with albinism. Sometimes difficult to distinguish
in young infants is a sensory nystagmus, where a defect in the visual system reduces
vision and causes
nystagmus. Causes include retinal dystrophies, congenital stationary night blindness
and structural ocular defects including optic nerve hypoplasia or dense bilateral
congenital cataracts.
Unilateral nystagmus can be the sign of an anterior visual pathway lesion. Seesaw
nystagmus may be associated with suprasellar and mesodiencephalic lesions and – rarely
– with retinal
dystrophies.
The ophthalmology plays a key role in identifying the form of nystagmus. Children
with new onset nystagmus, with spasmus nutans, with vertical or unilateral nystagmus
and those with seesaw
nystagmus require neurologic evaluation including imaging of the brain.
The treatment of nystagmus depends on the underlying cause. Even minor refractive
errors should be corrected, contact lenses offer advantages over glasses.
Gabapentin and memantine, possibly also carbonic anhydrase inhibitors, are effective
in treating IIN, nystagmus in albinism and sensory nystagmus. Nevertheless, pharmacologic
treatment of
nystagmus is rarely used in children; the reasons are the limited effects on vision,
the need for lifelong therapy, and potential side effects. Eye muscle surgery (Anderson
procedure,
Kestenbaum procedure) can correct a nystagmus-related anomalous head posture. The
concept of “artifical divergence” of Cüppers may help to decrease nystagmus intensity
in patients whose
nystagmus dampens with convergence. The four-muscle-tenotomy, which involves disinsertion
and reinsertion of the horizontal muscles at the original insertion of both eyes,
has a proven but
limited positive effect on visual acuity.
Schlüsselwörter
Nystagmus - Kind - Diagnose - Therapie - ophthalmologische Chirurgie - Kopfzwangshaltung
Key words
nystagmus - child - diagnosis - therapy - eye surgery - anomalous head posture