BROWN SYNDROME

HISTORY

Brown syndrome was first discovered by Harold Brown in 1950 when he studied patients with an unusual motility disorder in the eye. It was characterized by;
divergence in straight upgaze (V pattern)
limited elevation in adduction
normal elevation in abduction
Compensatory chin elevation for binocular fusion.
He attributed this disorder to a short or tight anterior superior oblique tendon sheath. In Brown’s classic study of 126 patients, there was a higher incidence of the syndrome in females (59%) than males (41%). The right eye involvement was 55%, the left eye 35%, and bilateral 10%.

CONGENITAL AND ACQUIRED CAUSES
Brown syndrome can be divided into two types congenital and acquired.

Congenital Brown Syndrome is a developmental abnormality that limits the eye at birth. A few theorical causes are;
1. A short and stiff superior oblique tendon complex that restricts ocular elevation
2. A form of congenital fibrosis of the superior oblique muscle
3. Tendon-slackening that comes from a telescoping elongation of the central tendon
4. A developed abnormality of the elastic-crossed fibers that normally allow the telescoping movement of the central tendon fibers

Acquired Brown Syndrome is an abnormal condition that is acquired in late childhood or adulthood of the eye. Some theorical causes are;
1. A rare acquired fibrosis of the superior oblique muscle
2. A superior oblique tendon tuck
3. A mass that displaces the tendon or a scleral buckling
4. Abnormal telescoping mechanism which can be constant or intermittent
5. Extensive scarring around the trochlea from trama or surgery which can restrict the tendon movement in both ways

TREATMENT

The treatments for Brown Syndrome are anti-inflammatory medication such as oral ibuprofen, oral corticosteroids and steroid injections in the area of the trochlea. Spontaneously resolution rarely occurs except in non-traumatic acquired cases. Congenital cases are unlikely to improve spontaneously; therefore, surgery should be considered.
The presence of chin elevation and severe limitation of elevation in adduction is the most important indication for surgery. MRI exams of the orbit may identify pathology for acquired Brown Syndrome; especially if pain, discomfort, signs of inflammation or an atypical pattern of strabismus is present.

For more information go to: http://www.emedicine.com/oph/topic552.htm