Korean J Ophthalmol.  2010 Dec;24(6):360-363. 10.3341/kjo.2010.24.6.360.

Brain Imaging Studies in Leber's Congenital Amaurosis: New Radiologic Findings Associated with the Complex Trait

• Yang HK
• Hwang JM
• Park SS
• Yu YS

• KMID: 1769090
• DOI: http://doi.org/10.3341/kjo.2010.24.6.360

Abstract

PURPOSE
To report the incidence and new findings of abnormal brain imaging studies associated with patients initially diagnosed with Leber's congenital amaurosis (LCA) without definite systemic abnormalities and to determine the need for brain imaging studies in these patients.
METHODS
A retrospective review of medical records was performed in 83 patients initially diagnosed as LCA and without definite systemic abnormalities before the age of 6 months in 2 tertiary referral centers. Brain magnetic resonance imaging was performed in 31 of 83 patients (37.3%).
RESULTS
Six of 31 patients (19%) had radiologically documented brain abnormalities. Two patients had cerebellar vermis hypoplasia, 1 patient showed an absence of septum pellucidum, 2 subjects showed mild external hydrocephalus, and 1 patient was found to have a small cerebellum.
CONCLUSIONS
Approximately one fifth of the LCA patients in whom brain imaging was performed were associated with brain abnormalities, including the absence of septum pellucidum, which has not been documented in the literature. Brain imaging is mandatory in patients primarily diagnosed with LCA, even without definite neurologic or systemic abnormalities.

Keyword

Cerebellar vermis hypoplasia; Leber's congenital amaurosis; Magnetic resonance imaging; Septum pellucidum

MeSH Terms

Brain/*pathology
Cerebellum/pathology
Female
Humans
Hydrocephalus/pathology
Infant
Leber Congenital Amaurosis/*diagnosis
*Magnetic Resonance Imaging
Retrospective Studies
Septum Pellucidum/pathology

Figure

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  Fig. 1 The T2 weighted axial magnetic resonance imaging of a Leber's congenital amaurosis patient (case 1) shows the absence of the septum pellucidum, which should normally be present in the area indicated between the black arrows. The hemispheric fissure is intact and indicated by the white arrows.

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