HEREDITARY BROWN SYNDROME

DR. JOSEPH KURIANPG STUDENT , ACME PARIYARAM

DEFINITION• Brown syndrome is a disorder of

elevation involving mechanical restriction of extra ocular movement.

• Brown was the first to describe this anomaly

• He suspected a congenitally short superior oblique tendon sheath to be the cause hence

“superior oblique tendon sheath syndrome”

INCIDENCE

• Incidence is low – 6 in 2583 (Croswell & Haldi )

• Familial occurrence is rare 2%(Birgit Lorenz, Michael C. Brodsky

)

• Usually unilateral but 10% is bilateral

• Syndrome can be : Congenital Acquired Constant Intermittent

SUPERIOR OBLIQUE MUSCLE

• Origin : Annulus of Zinn at the orbital apex, medial to optic canal

• Insertion :Outer posterior quadrant of the eyeball (insertion line 11mm)

• Artery : Lateral muscular branch of the ophthalmic artery

• Nerve : Trochlear nerve

SUPERIOR OBLIQUE MUSCLE

• Actions : Primary action Intorsion Secondary actions Abduction  Depress the eyeball

AETIOLOGY

AETIOLOGY1. Anomalies of Superior Oblique Tendon

Sheath

2. Anomalies of Superior Oblique tendon

► Shortening of tendon due to development anomalies

AETIOLOGY3. Anomalies of Inferior oblique & adjacent

structures

► Dense attachments causing restriction of action

4. Impaired slippage of tendon through Trochlea

► Anomalies of Trochlea ►Retro bulbar thickening of tendon

AETIOLOGY5. Acquired causes

► Post operative after superior oblique tucking surgery, scleral buckling & Molteno implant

► Trauma to orbital roof

► Inflammatory conditions like Rheumatoid arthritis

CLINICAL FEATURES CONSISTENT

• Absence of elevation in adduction

• Normal elevation in abduction

• Forced duction test shows restriction in adduction

CLINICAL FEATURES VARIABLE• Mild limitation of elevation in primary gaze

• Down shoot in adduction

• Widening of palpebral fissure

• Hypotropia in primary position

• Compensatory head posture>Head Tilt ,Chin lift

DIAGNOSISI. Inability to elevate eye in adduction

II. Normal elevation in abduction

III. Forced Duction Test shows resistance in adducted position to elevation

DIFFERENTIAL DIAGNOSISi. Paralysis of Inferior oblique muscle

ii. Congenital fibrosis of inferior rectus muscle

iii. Grave’s ophthalmopathy

CASE HISTORY 8yr old girl presented to our ophthal OPD

. Her mother had noticed squinting in the RE in certain gaze positions. No complaints of diplopia .

Family History: Father gives history of squint in LE. He is a diagnosed case of Browns syndrome in LE.

ON EXAMINATION DaughterHead posture Normal

Hirschberg Test Central

Cover Test Orthophoria in primary gaze

ON EXAMINATION Daughter RE LE

Extra ocular Restriction in Equal & fullmovement elevation on adduction

Forced duction Resistance to Normal test elevation on adduction

ON EXAMINATION FatherHead posture Normal

Hirschberg Test Central

Cover Test Orthophoria in primary gaze

ON EXAMINATION Father

RE LE

Extra ocular Equal & full Restriction inmovement elevation on adduction

Forced duction Normal Resistance to test elevation on adduction

TREATMENTINDICATIONS:

i. Involved eye hypotropic in primary gaze position

ii. Significant anomaly in head posture Head tilt towards affected side Chin lift

TREATMENTPROCEDURES Complete Tenectomy of Superior Oblique

muscle. * Forced duction test becomes negative * In case of symptoms of superior oblique

paralysis consider recession of contra lateral IR muscle or ipsilateral IO muscle.

TREATMENTSilicon superior oblique tendon expanders

to lengthen tendon * Preferred procedure * Advantage: No symptoms of SO

palsy

REFERENCES• BINOCULAR VISION & OCULAR

MOTILITY 5th edition by Gunter K von Noorden

• DELHI JOURNAL OF OPHTHALMOLOGY vol 22

• KANSKI BOWLING 7th edition

THANK YOU