Strabismus For Medical Students & GP

1. Strabismus For Medical Students & GP Samir Jamal MD, FRCSC KAUH

2. Strabismus • Misalignment of one or both eyes so as the eye (eyes) is not looking straight at the object of regard.

3. Significance In Children • Children need normally aligned eyes to develop vision. • Strabismus in childhood is the second most common presentation of retinoblastoma. • Strabismus is a common presentation for refractive errors.

4. Significance in Adults • Frequent sign of neurological disease • Frequent presentation of systemic disease ( Thyroid disease & Myasthenia) • Cosmetology

5. Types of Eye Movements • Horizontal direction • Vertical direction • Torsional direction All superior muscles are intortors. All inferior muscles are extortors.

6. Anatomy & Physiology

7. Anatomy & Physiology

8. Types of Strabismus • Esodeviation  eye turned in • Exodeviation  eye turned out • Hyperdeviation  eye turned up • Hpodeviation  eye turned down

9. Classification of Strabismus • Constant or intermittent • Latent or manifest (phoria or tropia) • Unilateral or alternating • Comitant or incomitant (restrictive or paralytic) • Paralytic or non-paralytic • Nuclear or supranuclear

10. Non-Accommodative Esotropia

11. Non-Accommodative Esotropia

12. Alternating Esotropia

13. Exotropia

15. Alternating Esotropia

17. Causes of Strabismus • Congenital: imbalance between innervations and contraction • Refractive errors • Loss of vision • Paralysis or Neuromuscular • Restrictive: thyroid eye disease • Tumors

18. Strabismus secondary to loss of vision from Cataract in Lt. eye

19. Presenting symptoms of Strabismus • Deviation of the eye (cosmesis) • Double vision • Torticollis (abnormal head posture) • Unexplained visual loss in a normal looking eye (Microtropia)

20. Abnormal Head Posture

21. Role of GP • Confirm Diagnosis • Decide on urgency • Teach patients • Referral to Ophthalmologist

22. Management of Strabismus History: 4 most important questions: • Age of onset • Constant or intermittent • Unilateral or alternating • Diplopia or torticollis

23. Management of Strabismus Examination: Three objectives: • Confirm the diagnosis • Diagnose type of strabismus • Differentiate paralysis from no paralysis

24. Examination of Strab Patient To achieve the first and second objectives we do: • Simple observation for the nasal white of the eye • Corneal light reflex • Cover test

26. Examination of Strab Patient To achieve the 3 rd objective we look for: • Presence of torticollis • Answer the following question: Is the strabismus the same in all directions of gaze or not i.e. comitant or incomitant? • Same = no paralysis. • Different = paralysis or restriction.

27. Examination • Test the extraocular movements in all directions of gaze. • Paralysis / restriction Limitation • No Paralysis No limitation

28. Doll's Head Manoeuvre • Used for testing the eye movement when the patient is uncooperative. • The eyes move in opposite direction to the head movement.

29. Common Forms of Esotropia • Congenital (No-Accommodative)  Surgery. • Accommodative  R/ Glasses. • P. Accommodative Glasses then surgery. • Sixth Nerve Palsy  observation for 6 M  surgery.

30. Accommodative Esotropia Before Glasses After Glasses

31. Non-Accommodative Squint Non-Accommodative Esotropia Before and After Surgery

32. Partially Accommodative Squint

33. Common Forms of Exotropia • Congenital exotropia Surgery • Sensory deprivation exotropia • Third nerve paralysis

34. Common Causes of Hypertropia or Hypotropia • Fourth nerve palsy • Third nerve palsy • Thyroid disease • Myasthenia gravis • Orbital floor fracture