J Korean Neurol Assoc.  2010 Feb;28(1):27-32.

Congenital Ocular Motor Apraxia: Clinico-Radiological Analyses

• Kim JS
• Oh YM
• Hwang JM
• Kim JH

Abstract

BACKGROUND
Congenital ocular motor apraxia (COMA) is characterized by impaired voluntary saccades and abnormal head thrusts. However, mechanism of this disorder remains to be elucidated.
METHODS
This study analyzed the eye movements and imaging findings in 16 patients with COMA, who had been recruited from 2003 to 2009 at the Neuro-Ophthalmology Clinic of Seoul National University Bundang Hospital.
RESULTS
All the children showed impaired saccades and smooth pursuit in the horizontal direction. One of them also exhibited impaired vertical saccades and smooth pursuit. Eight children showed excessive blinks in association with an attempt to generate saccades. The typical head thrust usually developed around the age of eight months and had resolved by the age of 6-7 years. History of spasmus nutans was confirmed in seven children. Fourteen children showed cerebellar vermian hypoplasia, mostly in the inferior portion, and five of them also had dysgenesis of the corpus callosum. The severity of cerebellar vermian hypoplasia was correlated with developmental delay, as determined by the age of independent walking.
CONCLUSION
Cerebellar vermian hypoplasia is a frequent finding in COMA. Dysfunction of the oculomotor vermis may responsible for the impaired saccades and smooth pursuit in COMA. The occasional association of COMA with spasmus nutans indicates a common pathophysiology of these benign developmental disorders.

Keyword

Ocular motor apraxia; Cerebellum; Hypoplasia; Saccades; Smooth Pursuit

MeSH Terms

Apraxias
Cerebellum
Child
Cogan Syndrome
Coma
Corpus Callosum
Eye Movements
Head
Humans
Infant
Infant, Newborn
Pursuit, Smooth
Saccades
Spasms, Infantile
Cogan Syndrome