Brown syndrome consists of an inability to elevate an eye in adduction. Other associated clinical features include an exodeviation in attempted upgaze and an ipsilateral hypodeviation that gets worse in upgaze.
Brown syndrome is caused by a mechanical restriction of the superior oblique tendon moving through the trochlea. The most common cause is a congenitally tight superior oblique muscle tendon complex, termed true congenital Brown syndrome.
The acquired form is usually caused by an inflammation around the superior oblique tendon and trochlea. The patient may complain of intermittent pain and tenderness on the superior nasal quadrant. The other causes of acquired or pseudo-Brown syndrome include orbital floor fracture, trochlear inflammation (such as in rheumatoid arthritis), peritrochlear scarring or superior oblique tendon sheath syndrome, glaucoma implant under the superior oblique tendon in the superior nasal quadrant, or fat adherence syndrome.
By assuming chin elevation and face turn away from the affected eye, most patients with Brown syndrome can fuse the images of the two eyes and have good binocular vision. Surgery is indicated when the compensatory head posture is unacceptable.
True congenital Brown syndrome is usually managed conservatively. It is better to wait until the child reaches visual maturity before any surgery is done because strabismus is not an uncommon complication of surgery and may lead to loss of binocular vision post-op. The most common indication for surgical treatment is a significant vertical deviation in primary position. Surgery consists of one of the many procedures to weaken the superior oblique tendon. The procedure of choice is superior oblique tenotomy with insertion of silicone tendon expander (Wright).
In contrast to the congenital form, inflammatory Brown syndrome may resolve spontaneously. Treatment options include oral non-steroidal anti-inflammatory medication, or local steroid injection in severe cases. Surgery is usually contraindicated.
Wright KW. Brown’s syndrome: diagnosis and management. Trans Am Ophthalmol Soc 1999; 97: 1023-1109