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Ocular features of CHARGE syndrome
Karen McMain1, Kim Blake, Isabel Smith
1Clinical Vision Science, Dalhousie University, Halifax, Nova Scotia, Canada. Karen.mcmain@iwk.nshealth.ca
Summary
CHARGE syndrome in Maritime Canada presents significant ocular and cranial nerve issues, including colobomas and severe hearing loss. Early identification of sensory deficits is vital for development.
Area of Science:
- Ophthalmology
- Neurology
- Genetics
Background:
- CHARGE syndrome is a complex genetic disorder with a wide range of congenital anomalies.
- Ocular and cranial nerve involvement are common but variable in presentation.
Purpose of the Study:
- To investigate the prevalence and severity of ocular and cranial nerve abnormalities in CHARGE syndrome patients from Maritime Canada.
- To characterize the specific ophthalmic and neurological findings in this population.
Main Methods:
- Prospective examination of nine individuals with CHARGE syndrome identified from a Canadian database.
- Ophthalmic and neurological evaluations to assess structural and sensorial defects impacting visual function.
Main Results:
- Colobomas, typically bilateral chorioretinal involving the optic nerve, were the primary ophthalmic finding.
- All participants had bilateral severe sensorineural deafness (cranial nerve VIII); 89% had facial nerve (cranial nerve VII) involvement.
- Anisometropia (89%), severe myopic astigmatism (72%), and limited elevation in adduction (33%) were notable findings, alongside strabismus, cataracts, and visual field defects.
Conclusions:
- The presence of coloboma with other CHARGE features suggests further investigation, including CHD7 gene screening.
- Prompt recognition and management of visual, auditory, and vestibular issues are critical for optimal psychomotor and cognitive development.
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