Brown Syndrome Clinical Presentation

• Diplopia may occur when the patient looks up and to the contralateral side of the affected eye.

  • Patients with congenital Brown syndrome rarely complain of diplopia, because most patients have developed suppression.
  • Patients with acquired Brown syndrome in late childhood or adulthood experience diplopia when tropic.
• Pain
• Some patients with acquired Brown syndrome present with inflammatory signs.
• These signs include supranasal orbital pain, tenderness, intermittent limitation of elevation in adduction, and pain that is associated with this ocular movement.

Characteristic physical findings include the following:

• Limited elevation in adduction, an invariable sign, is the hallmark of Brown syndrome. The amount of limited elevation in adduction can range from minimal (-1) to severe (-4). The severe form has been termed Brown plus. Even in severe cases of congenital Brown syndrome, there is minimal hypotropia in primary position and no hypotropia in downgaze.
• A significant limitation of elevation in abduction is present in 70% of patients, but it is the difference between elevation in adduction versus elevation in abduction that differentiates Brown syndrome from such disorders as double elevator palsy (where elevation is equal to or worse in abduction).
• A lack of significant hypotropia in primary position in cases of nontraumatic Brown syndrome has been observed. In contrast, much larger hypotropias have been observed in cases of Brown syndrome associated with trauma or periorbital surgery.
• If the vertical deviation in primary position is greater than 10-12 PD, consider an inferior oblique palsy, severe periocular scarring, or a superior nasal mass; do not consider Brown syndrome caused by a tight or inelastic superior oblique tendon.
• Patients often present with compensatory head-posturing, their chin up, and a contralateral face turn to avoid the hypotropia that increases in upgaze and gaze to the contralateral side of the affected eye.
• Amblyopia can occur in patients with Brown syndrome, but the incidence compared with the general population is low in most patients with good binocular fusion.
• Minimal or no superior oblique overaction and positive forced ductions up and in are present. The presence of even mild superior oblique overaction should be regarded with suspicion, since this finding is inconsistent with Brown syndrome of superior oblique tendon etiology.
• A feature that often is associated with acquired Brown syndrome is an audible or palpable superior nasal click on ocular rotations up and nasalward; sometimes, the pain is associated with this ocular movement.
• Digital pressure in the area of the trochlea can unlock and improve ocular rotations in some cases.
• Contralateral pseudoinferior oblique overaction occurs because of the limited elevation in abduction.

  • Because of the Hering law of yoke muscles, increased innervation to the contralateral inferior oblique muscle occurs as the eye with Brown syndrome tries to elevate and abduct.
  • Apparent inferior oblique overaction disappears when the superior oblique restriction is relieved.
• The positive forced ductions maneuver is a critical part of the syndrome; it equals the limitation that is seen on ductions and versions.
• A positive forced ductions test, by itself, does not indicate a tight superior oblique muscle tendon as the cause of Brown syndrome. Nonsuperior oblique restrictions (eg, inferior orbital adhesions) can restrict ocular elevation in adduction.
• Objective fundus torsion: In Brown syndrome secondary to a tight superior oblique tendon, intorsion occurs as the eye moves up and encounters the tight superior oblique tendon. Clinically, no torsion occurs in primary position or downgaze, but intorsion in upgaze does occur. Fundus torsion is shown in the images below. Fundus torsion (direct view). The bottom set of fundus photographs represents downgaze; the center photographs, primary position; and the top photographs, upgaze. Note that in the top set of photographs, the left fundus is intorted as the foveal fixation is slightly above the top of the optic disc. Courtesy of Kenneth Wright, MD.
• The images below show acquired Brown syndrome. A 3-year-old patient with acquired right Brown syndrome. Marked limitation of elevation in adduction is present in the right eye. Pseudo-overaction of the left inferior oblique is present. Courtesy of Kenneth Wright, MD. The same patient as in the image above, 6 years later. The patient shows normal eye movements, and no signs of Brown syndrome. A spontaneous resolution occurred over a 2-year period. Courtesy of Kenneth Wright, MD. Composite photographs, showing left Brown syndrome with marked limitation of elevation in adduction. Courtesy of Kenneth Wright, MD.

The classification/potential causes of Brown syndrome are as follows:

• Congenital onset

  • Congenital Brown syndrome
    • Inelastic muscle-tendon complex (Wright hypothesis)
    • Anomalies of the superior oblique tendon fibers
  • Congenital pseudo-Brown syndrome
    • Anomalous inferior orbital adhesions
    • Posterior orbital bands
• Acquired onset

  • Acquired Brown syndrome
    • Peritrochlear scarring and adhesions - Chronic sinusitis, trauma (superior temporal orbit), blepharoplasty and fat removal, and lichen sclerosus et atrophicus and morphea
    • Tendon-trochlear inflammation and edema - Idiopathic inflammatory (pain and click), trochleitis with superior oblique myositis, acute sinusitis, adult rheumatoid arthritis, juvenile rheumatoid arthritis, systemic lupus erythematosus, possibly distant trauma (cardiopulmonary resuscitation [CPR] and long bone fractures), and possibly postpartum hormonal changes
    • Superior nasal orbital mass - Glaucoma implant and neoplasm
    • Tight or inelastic superior oblique muscle - Thyroid disease (inelastic muscle), peribulbar anesthesia (inelastic tendon), Hurler-Scheie syndrome (inelastic tendon), and superior oblique tuck (short tendon)
    • Idiopathic
  • Acquired pseudo-Brown syndrome
    • Floor fracture
    • Retinal band around inferior oblique muscle
    • Inferior temporal adhesions