Strabismus and Eye Muscle Surgery

1. Strabismus and Eye Muscle Surgery

6. Nomenclature Orthorphoria o Esophoria E Esotropia ET Intermittent Esotropia E(T) Exophoria X Exotropia XT Intermittent Exotropia X(T) At near X(T)� Right Hypertropia RHT

7. Right Hypertropia

8. Strabismus Why is it Important? Preserving Stereo acuity 8 yo with worsening X(T) Intermittent Exotropia. Enlarging Visual field for Pts with ET. Appearance Would you hire me? Would you date me? Is there something wrong with you?... Diplopia

10. Accommodative esotropia Typically presents around age 2 years, may present acutely. Always put +3.00 sph OU when you see an ET for the first time. If its improved or resolved think Accom ET! Why is there ET with Accommodation? Eyes will usually converge when accommodation is attempted. If high hyperope then must accommodate, if accommodating then will converge, cross, specially at near.

11. Accommodative ET Use cyclogyl to measure Rx (wait 40 minutes) Recheck 4 weeks later with glasses, If still some ET present, use Atropine to make sure you measured the full CRx Tell parents they eyes will continue to cross every time the glasses come off. Always give full CRx, cycloplegic refraction for suspected Accom ET. Child might not like full CRx ? Use Atropine when using hyperopic glasses for the first time, it will break the accommodative spasm and allow the pt to get used to the glasses.

14. Accommodative ET, AC/A AC/A = Accommodative convergence / accommodation An accom ET crosses because he/she has normal AC/A. Ie of high AC/A: an emmetrope, WRx = plano OU pt At Distance they are ortho At near they are 25PD ET� They are over converging for a normal amount of accommodation. This is a high AC/A ratio.

15. AC/A Example of a pt with low AC/A? who underconverges? +8.00 hyperope who is ortho at near and distance. They have adapted to their hyperopia by under converging.

17. Infantile esotropia continued Must rule out other causes CN 6 palsy from birth? Often spontaneous resolution Remember some variable, intermittent strabismus is expected until 4 months of age.

18. Esotropia associated with Viral illness Often self limited, will spontaneously resolve in 3-6 months. Acute Not improved with hyperopic glasses. Consider ruling out neoplastic causes. Treat/prevent amblyopia in the mean time

19. Esotropia associated with Diabetes Abducens, lateral, CN 6 usually affected. Isolated unilateral palsy Ischemic Usually resolves after 4-6 months. Consider Botox in the meantime, to which muscle�

21. Add droopy lid

22. Sensory strabismus - Peds Young pts with poor monocular vision will often develop esotropia in that eye. OKAP NOTE:::::::: DOES YOUR PEDS PT HAVE ESOTROPIA BECAUSE THEY CAN NOT SEE OUT OF THAT EYE? WHY? CATARARCT, RETINOBLASTOMA, MACULAR SCAR, ANISOMETROPIA?

24. Duane�s Syndrome ALL FORMS RETRACT IN ADDUCTION Abda Dubba Deux Type I: deficit in abduction and retraction in adduction (due to co-contraction of MR and LR Type II: deficit in adduction Type III: both. Watch for strabismus, face turn: attitude Usually sporadic, also think Goldenhars, Wildervanck syndromes OS more common than OD Females > males Watch also for vertical pull, leashing phenomenom. Occasional absent CN 6 nucleus.

25. Duane�s Syndrome Type I: OSlimited abduction, retraction in adduction

26. Duane�s Syndrome Type Ilimited abduction, retraction in adduction: superior viewnotice co-contraction of LMR & LLR

27. Duane�s Syndrome Type I retraction in adduction limited abduction, superior view

28. Duane�s Syndrome Type II: OSlimited adduction retraction in adduction

29. Duane�s Syndrome Type III: OSlimited adduction and abduction retraction in adduction

30. Funny Story� 15 yo wm Bad attitude� ortho�?

31. Funny Story� 15 yo wm Bad attitude� ortho�? 30 PD LET actually, But can fuse in right gaze, left head turn

32. Funny Story� 15 yo wm Bad attitude� ortho�? 30 PD LET actually, But can fuse in right gaze, left head turn And, I forgot to notice the limited abduction and narrow fissure in adduction

33. Duane�s Syndrome Type I: OSlimited abduction, retraction in adduction

34. Duane�s treatment If strabismus in 1ry position ET>XT Or significant head turn: attitude. Never resect LR if no abduction. This will worsen globe retraction and not improve abduction.

42. Exotropia Intermittent is very common How symptomatic are they? Make sure they have BCVA glasses Diplopia? Often familial, so what? Dad had it too. �What hump?� Intermittent exotropia can breakdown over time, check serial stereo. If worsening think surgery. Most common time of pediatric surgery is 7 years old. Can the pt converge?

43. Convergence insufficiency Seen in kids who have trouble reading Adults with Parkinson�s disease Sometimes over diagnosed by some vision therapy developmental optometrist. Consider Convergence exercises by an orthoptist, or software Decreasing add in bifocals to extend reading distance (holding reading material further away) Prisms, etc. pencil pushups.

44. Nomenclature Orthorphoria o Esophoria E Esotropia ET Intermittent Esotropia E(T) Exophoria X Exotropia XT Intermittent Exotropia X(T) At near X(T)� Right Hypertropia RHT

48. Alternate cover test Remember to allow the pt time to fixate on the target, give them a minute. Then quickly cover the other eye to prevent the pt from regaining fusion. But do not go back and forth quickly because the pt will not have time to refixate.

54. Constant Strabismus Workup, acute presentation, nerve palsy (Case of newly acquired left CN 6 in a 55 yo male) Ischemic, GCA Neoplastic Invasive Paraneoplastic Compressive Nerve regeneration Longstanding breakdown. Sensory Degenerative CNS, Parkinson�s, MS Infectious Myositis (trichinosis) Iatrogenic Post non-strabismus surgery Cataract, retrobulbar blocks (nerve damage vs. contracture) Glaucoma, valves Lasik Mechanical Trauma Blow out Fracture Tumor

55. More Types of Strabismus Convergent, Esotropia Accommodative Congenital or infantile Acquired, CN 6 palsies Divergent, Exotropia Vertical, Torsional and Oblique Parks 3 Step test Superior Oblique Palsies Tucks vs. IO recessions Inferior Oblique Over action (V patterns) DVD�s Dissociated Vertical Deviation Complex Cases Adjustable vs Fixed sutures. Re-ops Different measurements based on eye fixation Optics Angle Kappa

57. Exotropia Remember to measure while fixating at a far distance. Also use +3.00 sph in front of each eye to eliminate the accommodative convergence component at distance. Consider 30 minute patch test to break fusion and really see how bad the XT can get.

58. How much to operate? How much to operate Tables: Personal experience Dosages (surgical) bilat , 2 muscles ie for ET 40PD recess 5.5mm both MR ET XT PD Rec Rst Rec Resect 15 3 3 4 2.5 20 3.5 4 5 3 25 4 5 6 4 30 4.5 6 7 5 35 5 7 7.5 5.5 40 5.5 7.5 8 6 50 6 8 9* 7 60 6.5 8.5 10* 8

60. Large ET (65PD) , bilateral MR recession, and LLR resection

61. How much to operate-Patient preference Case of monocular 85 yo BF with sensory XT one eye or two? Pt wished to not have OD operated, understood risk of under correction. Therefore only recessed LMR 7mm and LLR 6mm. Pt had some residual XT 15-20 PD, but was happy, therefore surgeon was happy too.

62. Surgical Notes Sutures: Most stitches used in eye surgery are thinner than human hairs. They will dissolve on their own over 6 weeks. They may make your eye feel scratchy for the first few weeks. The antibiotic ointment and a cool compresses will alleviate this symptom if it occurs. Adjustable sutures What to expect after surgery Some double vision is normal for the first few weeks after eye muscle surgery. Precaution: General post op hygiene Eye rubbing Can my child swim after his or her eye surgery? Length of surgery and recovery

63. Notes on Anesthesia Notes on Anesthesia General Pediatric anesthesia doctors Risk of Gen. Anesthesia in children Primary MD clearance

64. Complications and Risks or surgery Infection (1 in 3 years, Tx oral Abx) Nausea (Tx: Phenergan, etc.) Blood loss (what blood loss, maybe a little more than corneal surgery) Loss of sight? (globe perforation) Scar tissue Diplopia Residual or consecutive strabismus Oculo-Cardiac Reflex � Bradycardia Tx: Atropine

65. When to operate? Or �When NOT to operate? Prisms Fresnels Permanent prisms Occlusion (non-operable, CNS disease) BCVA (sharp image will often help pt fuse)

66. When not to operate cont. Botox best for small, new, noncontractile strabismus, ie ischemic CN 6 palsy. Or very variable strabismus ie cerebral palsy, to prevent contracture and save time. Exercises, best for convergence insufficiency X(T)�. Small Magnitude (<8 PD) Tolerability, symptoms head position, career, lifestyle Surgeon aggressiveness, cut, cut, cut Pre-existing Amblyopia (how much to treat before surgery?) Angle Kappa pseudo XT�

67. How to operate Go to Recession and Resection Lectures

68. Add skew deviations and Different angle measured depending on fixation.