Brown_Syndrome_30_Slides_White_Font.pptx

cornealdystrophies

1. Brown Syndrome Overview Vertical strabismus with limited elevation in adduction Mechanical restriction of SO tendon-trochlea complex Can be congenital or acquired Slight female predominance, ~10% bilateral

2. Epidemiology More common in females 10% of cases are bilateral Most congenital cases are sporadic Genetic predisposition suggested

3. Clinical Presentation Limited elevation of affected eye in adduction Possible head tilt or chin-up posture Diplopia may be present Pain or 'clicking' sensation in acquired cases

4. Congenital vs Acquired Congenital: present from birth, painless Acquired: onset later in life, often painful Acquired may be intermittent Associated with systemic/inflammatory causes

5. Historical Background Described by Dr. Harold Brown (1950) Originally named 'SO tendon-sheath syndrome' Now understood as trochlear-tendon abnormality Recent theories include CCDD

6. Pathophysiology SO tendon doesn't slide freely through trochlea Can be fibrotic, thickened, or adhesed May restrict globe movement on elevation in adduction Anomalies can be seen during surgery

7. Tendon-Trochlea Abnormalities Adhesions and fibrosis are common Some cases show fibrotic band behind trochlea Restrictive movement leads to vertical strabismus

8. CCDD Hypothesis Congenital Cranial Dysinnervation Disorders Developmental nerve miswiring May affect SO function or coordination

9. Acquired Causes Trauma or scarring near trochlea Orbital mass or cyst Sinusitis or orbital inflammation Iatrogenic from surgery

10. Systemic Associations Rheumatoid arthritis Juvenile idiopathic arthritis Systemic lupus erythematous Thyroid eye disease

11. Symptoms Vertical diplopia Orbital pain or tenderness Clicking sound with movement Reduced stereopsis

12. Head Posture and Compensation Chin up posture common Head turned away from affected eye Adopted to maintain binocular fusion

13. Eye Movement Patterns Limited elevation in adduction Possible downshoot in adduction V-pattern on upgaze in some cases

14. Differentiation from IO Palsy Both limit elevation in adduction IO palsy has no restriction on forced duction Brown shows mechanical resistance

15. Forced Duction Testing Gold standard diagnostic test Performed under anesthesia in children Shows resistance on elevation in adduction

16. Imaging and Workup Orbital CT/MRI for mass or cysts Lab tests in inflammatory cases Assess systemic autoimmune activity

17. Mild Cases May show no vertical deviation in primary gaze May go unnoticed unless tested in 9 gazes No downshoot

18. Moderate Cases Downshoot in adduction No deviation in primary gaze May require observation or treatment

19. Severe Cases Hypotropia in primary position Significant downshoot in adduction Obvious abnormal head posture

20. Observation Approach Used in mild congenital cases Up to 75% resolve spontaneously Follow for signs of deterioration

21. Medical Management NSAIDs or systemic steroids Immunosuppressants for systemic causes Steroid injection near trochlea

22. Surgical Indications Significant hypotropia Persistent diplopia Severe head posture Orbital pain or downshoot

23. Surgical Options I SO tenotomy or tenectomy Often paired with IO recession Can lead to SO palsy

24. Surgical Options II SO tendon lengthening Silicone band or split tendon Preferred due to fewer complications

25. Other Surgical Techniques SO tendon thinning Cyst removal in mass-related cases Plication reversal if iatrogenic

26. Prognosis Excellent in congenital cases Acquired may resolve with treatment Surgery yields good outcomes in indicated cases

27. Case Study (Optional) 6-year-old female with limited elevation in adduction Chin-up posture, pain on movement Diagnosis confirmed with FDT Managed conservatively with NSAIDs

28. Summary Brown Syndrome = restriction of SO tendon Diagnose with forced duction test Treat based on severity and etiology Surgery reserved for symptomatic cases

29. References [1]–[16] as cited in main document

30. Q&A Thank you for your attention Any questions?