Reuben Oza
Introduction
Brown syndrome, which is also referred to as superior oblique tendon sheath syndrome, describes a rare presentation of vertical strabismus in which there is restricted ability to elevate the affected eye when it is adducted (1). This article aims to highlight the pathophysiology, clinical features, associations, diagnosis and management of this visual phenomenon which was initially reported in 1949 by Dr Harold Whaley Brown (2).
Pathophysiology
Brown syndrome occurs due to dysfunction of the superior oblique muscle. Theories differ as to the exact pathology affecting the muscle, but it is thought that Brown syndrome may be secondary to the superior oblique muscle being either too short or tight, preventing full range of movement (3). Identification of a fibrotic strand at the posterior part of the superior oblique tendon during surgical treatment of Brown syndrome has given rise to a more recent theory that it is this strand of fibrosis that causes the restriction in range of movement of the superior oblique muscle (2).
Clinical Features
In majority of cases, Brown syndrome presents unilaterally, and more commonly affects females than males. The affected eye characteristically has impaired elevation when held in adduction. Affected patients may describe vertical diplopia, eye pain, difficulty looking upwards, and/or a popping sensation when trying to move the affected eye upwards and inwards (4).
Associations
Some patients may have congenital Brown syndrome, in which they are affected from birth. In others, Brown syndrome develops in later life, with acquired causes including autoimmune disease, such as rheumatoid arthritis and Sjrögen’s syndrome, infectious diseases, such as sinusitis and orbital cellulitis, and trauma (4).
Diagnosis
Diagnosis of Brown syndrome is dependent on history and examination. The characteristic sign of Brown syndrome on assessment of oculomotor movement, is a V pattern strabismus on upward movement of the eye (5). In Brown syndrome, a positive forced duction test is noted, in which there is resistance when the affected eye is manually elevated in the adducted position. Another notable feature which may be seen on assessment includes hypotropia of the affected eye in its neutral position. In acquired cases, investigation for the precipitating cause include serological testing to identify infectious/autoimmune causes, or orbital imaging to identify traumatic causes (1).
Management
Approach to management of Brown syndrome is largely dictated by severity of disease and underlying cause. If mild cases, a period of observation may be used to ascertain if cases will improve with time. In cases where Brown syndrome occurs secondary to infectious or autoimmune causes, medical control of inflammation with non-steroidal anti-inflammatory drugs or steroids may result in improvement of Brown syndrome (4). If particularly severe, or not self-resolving, a surgical approach can be taken. Surgical management centres around weakening the superior oblique tendon by either lengthening the tendon or performing a tenotomy (1).
References
- Tsakiris KA, Seely KR, Kumar A, Adamopoulou C, Akkara JD, Saluja G, et al. Brown Syndrome. EyeWiki [Internet]. 2024 Dec 27 [cited 2025 Sep 7]. Available from: https://eyewiki.org/Brown_Syndrome
- Fu L, Gurnani B, Malik J. Brown Syndrome. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Mar 3 [cited 2025 Sep 7]. Available from: https://pubmed.ncbi.nlm.nih.gov/33085357/
- Moorfields Paediatric Information Group. Brown syndrome (teens + parents) [Internet]. London: Moorfields Eye Hospital NHS Foundation Trust; approval Mar 2018 [cited 2025 Sep 7]. Available from: https://www.moorfields.nhs.uk/mediaLocal/osdl3gk4/brown-syndrome-teens-plus-parents.pdf
- Cleveland Clinic. Brown Syndrome: What It Is, Causes & Treatment [Internet]. Cleveland (OH): Cleveland Clinic; [cited 2025 Sep 7]. Available from: https://my.clevelandclinic.org/health/diseases/24195-brown-syndrome
- Khorrami-Nejad M, Azizi E, Tarik FF, Akbari MR. Brown syndrome: a literature review. Ther Adv Ophthalmol. 2024 Feb 22;16:25158414231222118. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC10893837/