Brown syndrome
- Introduction
- Clinical features
- Classification
- Incidence
- Etiology
- Acquired form
- Congenital form
- Treatment
- References
- In 1950, Brown reported a motility disorder characterised mainly by deficient elevation of the eye in adduction. Originally it was termed superior oblique tendon sheath syndrome. It is now known as Brown's syndrome.
- deficient elevation in adduction
- less elevation deficiency in midline
- minimal or no elevation deficit in abduction
- minimal or no superior oblique overaction
- divergence in upgaze producing a V-pattern
- positive forced duction testing
- downshoot in adduction
- widened palpebral fissure in adduction
- anomalous head posture: chin-up &/or face-turn away from affected eye
- primary position hypotropia
- congenital vs acquired
- constant vs intermittent
- severity:
- mild: deficient elevation in adduction no hypotropia or downshoot in adduction
- moderate: deficient elevation and downshoot in adduction no hypotropia in primary position
- severe: deficient elevation and downshoot in adduction hypotropia present in primary position commonly associated with an abnormal head posture
- Brown's syndrome occurs in 10 to 24 % of vertical muscle anomalies.
- The right eye is more commonly affected than the left eye.
- Females have a greater incidence than males (3:2).
- Brown called it superior oblique tendon-sheath syndrome thinking it was caused by a shortened anterior sheath of superior oblique tendon; this theory has been shown to be incorrect.
- Disturbance of free tendon movement through the trochlear pulley (i.e. a stenosing tenosynovitis of the trochlea).
- Usually intermittent and associated with an audible "click".
- Associated with inflammation and trauma such as rheumatoid arthritis, juvenile arthritis, collagen vascular diseases, trochlear bursitis, sinus surgery, orbit or muscle surgery, scleral buckling and glaucoma implant surgery.
- Canine tooth syndrome refers to a posttraumatic condition that produces scarring in the trochlear region such that movement of the tendon in either direction is restricted producing a combined Brown`s syndrome and superior oblique palsy.
- It is possibly secondary to a short and inelastic superior oblique muscle and tendon.
- Inflammation, trauma and stenosis may be contributing factors.
- Fibrous adhesions may be present around the trochlear area.
- Spontaneous resolution is possible and improvement can occur in time.
- Observation alone is the most common suggested management for all forms of Brown's syndrome.
- Spontaneous regression is common in acquired and intermittent cases and less common in congenital and constant cases.
- Motion eye exercises and local/systemic steroids have been showed to improve the condition in selected patients.
- If Brown's syndrome occurs in association with a systemic inflammatory disease, resolution can occur when the systemic disease is in remission.
- Surgery is usually indicated for primary position hypotropia and/or anomalous head posturing.
- Superior oblique tenotomy is effective but produces a superior oblique palsy with overacting ipsilateral inferior oblique 44 to 82% of the time.
- Superior oblique recession nasally using a silicone spacer (Wright) is also effective and avoids this complication.
- Brown HW: True and simulated superior oblique tendon sheath syndromes.Doc Ophthalmol 1973 Feb 21; 34(1): 123-36
Link to Reference. - Buckley EG, Flynn JT: Superior oblique recession versus tenotomy: a comparison of surgical results.J Pediatr Ophthalmol Strabismus 1983 May-Jun; 20(3): 112-7
Link to Reference. - Clarke MP, Bray LC, Manners T: Superior oblique tendon expansion in the management of superior oblique dysfunction.Br J Ophthalmol 1995 Jul; 79(7): 661-3
Link to Reference. - Clarke WN, Noel LP: Brown's syndrome with contralateral inferior oblique overaction: a possible mechanism.Can J Ophthalmol 1993 Aug; 28(5): 213-6
Link to Reference. - Helveston EM, Birchler C: Superior oblique palsy:subclassification and treatment suggestions.Am Orthopt 1982; 32: 104-110.
- Helveston EM, Merriam WW, Ellis FD: The trochlea. A study of the anatomy and physiology.Ophthalmology 1982 Feb; 89(2): 124-33
Link to Reference. - Parks MM, Brown M: Superior oblique tendon sheath syndrome of Brown.Am J Ophthalmol 1975 Jan; 79(1): 82-6
Link to Reference. - Parks MM: Bilateral superior oblique tenotomy for A-pattern strabismus in patients with fusion (commentary).Binoc Vis 1988; 3: 39.
- Prieto-Diaz J: Posterior tenectomy of the superior oblique.J Pediatr Ophthalmol Strabismus 1979 Sep-Oct; 16(5): 321-3
Link to Reference. - Scott AB, Knapp P: Surgical treatment of the superior oblique tendon sheath syndrome.Arch Ophthalmol 1972 Sep; 88(3): 282-6
Link to Reference. - Scott WE, Jampolsky AJ, Redmond MR: Superior oblique tenotomy: indications and complications.Int Ophthalmol Clin 1976 Fall; 16(3): 151-9
Link to Reference. - Von Noorden GK: Binocular Vision and Ocular Motility.St. Louis: CV Mosby; 1996:437-442.
- Wright KW: Surgical procedure for lengthening the superior oblique tendon.Invest Ophthamol Vis Sci 1989; 30(sup): 377.
- Wright KW: Superior oblique silicone expander for Brown syndrome and superior oblique overaction.J Pediatr Ophthalmol Strabismus 1991 Mar-Apr; 28(2): 101-7
Link to Reference. - Wright KW: Color Atlas of Ophthalmic Surgery-Strabismus.Philadelphia, Pa: Lippincott; 1991:201-219.
- Wright KW, Min BM, Park C: Comparison of superior oblique tendon expander to superior oblique tenotomy for the management of superior oblique overaction and Brown syndrome.J Pediatr Ophthalmol Strabismus 1992 Mar-Apr; 29(2): 92-7; discussion 98-9
Link to Reference. - Wright KW, Silverstein D, Marrone AC: Acquired inflammatory superior oblique tendon sheath syndrome. A clinicopathologic study.Arch Ophthalmol 1982 Nov; 100(11): 1752-4
Link to Reference. - Wright KW: Brown's syndrome: diagnosis and management.Trans Am Ophthalmol Soc 1999; 97: 1023-109
Link to Reference.
