Magnetic resonance imaging in congenital Brown syndrome.
OBJECTIVE
Our aim was to elucidate the etiology of Brown syndrome by evaluating the trochlea position, morphologic characteristics of the extraocular muscles including superior oblique muscle/tendon complex, and the presence of the cranial nerves (CN) III, IV, and VI using magnetic resonance imaging (MRI) in eight patients with unilateral congenital Brown syndrome and one patient with bilateral congenital Brown syndrome.


METHODS
Nine consecutive patients diagnosed with congenital Brown syndrome had a comprehensive ocular examination and MRI for the CN III, CN VI, and the extraocular muscles. Five of the nine patients underwent additional high resolution MRI for CN IV. The distance from the annulus of Zinn to the trochlea was measured.


RESULTS
Normal sized CN III, IV, and VI, as well as all extraocular muscles, could be identified bilaterally in all patients with available MRI. The distance from the annulus of Zinn to the trochlea was the same in both eyes.


CONCLUSIONS
The findings for our patients, particularly in those who underwent additional high resolution MRI, did not provide evidence of a lack of CN IV as a cause of Brown syndrome.
Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
Jae Hyoung
JH
Kim
Jeong-Min
JM
Hwang
D000010:Abducens Nerve / Q000002:abnormalities; D002648:Child; D005124:Eye Abnormalities / Q000175:diagnosis; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D015835:Ocular Motility Disorders / Q000151:congenital* / Q000175:diagnosis* / Q000209:etiology; D009801:Oculomotor Muscles / Q000294:innervation; D009802:Oculomotor Nerve / Q000002:abnormalities; D013710:Tendons / Q000294:innervation; D014321:Trochlear Nerve / Q000002:abnormalities