Consecutive Exotropia Consecutive Exotropia 1. General comments1. General comments

2. Surgical audit2. Surgical audit

Lionel Kowal, Lionel Kowal, DirectorDirector

Elaine Wong, Elaine Wong, 2005 Registrar & 2006 Fellow2005 Registrar & 2006 Fellow

OCULAR MOTILITY CLINICOCULAR MOTILITY CLINIC

& CERA, RVEEH, MELBOURNE& CERA, RVEEH, MELBOURNE

CONSECUTIVE XTCONSECUTIVE XT

Any XT happening after previous ET Any XT happening after previous ET [usually after ET surgery][usually after ET surgery]

Rare: spontaneous consecutive XTRare: spontaneous consecutive XT

Old medial rectus Surgery

CONSECUTIVE XT - WHY?CONSECUTIVE XT - WHY?

Ciancia: CET. n=390.Ciancia: CET. n=390.perfect early alignment after Cong ET surgery perfect early alignment after Cong ET surgery 30%30%

consec XT over next 25yconsec XT over next 25y

Reason #1:Reason #1:If repositioned MR successfully aligns the eyes, If repositioned MR successfully aligns the eyes,

subsequent growth of globe, muscle, orbit may alter subsequent growth of globe, muscle, orbit may alter this mechanical ‘balance’ this mechanical ‘balance’ mechanical disadvantage mechanical disadvantage of repositioned MR *of repositioned MR *

The ET correction doesn’t ‘grow’ with the pt *The ET correction doesn’t ‘grow’ with the pt *

**Speculative - no evidenceSpeculative - no evidence

The ET correction doesn’t ‘grow’ The ET correction doesn’t ‘grow’ with the ptwith the pt

Globe growth:Globe growth: ? Rc changes the way the ? Rc changes the way the sclera anterior to the new insertion subsequently sclera anterior to the new insertion subsequently grows : a 5mm Rc becomes a 7mm Rc *grows : a 5mm Rc becomes a 7mm Rc *

**Speculative - no evidenceSpeculative - no evidence

Core defect in consec XTCore defect in consec XT

Usually medial rectus underactionUsually medial rectus underaction RRxx: Have to make MR function normal [or : Have to make MR function normal [or

near- normal] for satisfactory long term near- normal] for satisfactory long term resultresult

#1 : L XT ‘A’ pattern L>R MR UA#1 : L XT ‘A’ pattern L>R MR UASO OA OUSO OA OU

L XT

XT greater on downgaze‘A’ pattern

Sup obl OA OU

MR UAL > R

#2, RMR UA#2, RMR UA

R XT

RMR UA

Right GazeLMR normal

#3, RMR UA#3, RMR UA

R XT

RMR UA

#4, LMR UA#4, LMR UA

LMR UA

L XT

Early consec XT - WHY?Early consec XT - WHY?More reasonsMore reasons

#2: Wrong surgical dose#2: Wrong surgical doseSurgical tables assume normal globe size, average muscle stiffness Surgical tables assume normal globe size, average muscle stiffness

[L-T curve], average scleral rigidity, average mechanical [L-T curve], average scleral rigidity, average mechanical response of antagonist, ….response of antagonist, ….

#3: Poor surgical technique#3: Poor surgical technique #4: Knots come undone #4: Knots come undone #5: Poor / aberrant early healing#5: Poor / aberrant early healingVicryl hydrolysis not uniformVicryl hydrolysis not uniform

Delayed consec XT - WHY?Delayed consec XT - WHY?

Reason #6Reason #6 ‘‘Stretched scar’ - look for stretchmarks, healing of other Stretched scar’ - look for stretchmarks, healing of other

surgical scars, ….surgical scars, …. Scar remodelling is an ongoing lifelong processScar remodelling is an ongoing lifelong process Scar is metabolically more active than tendonScar is metabolically more active than tendon

Ludwig IH Ludwig IH J AAPOS. 2000 & Trans Am J AAPOS. 2000 & Trans Am Ophthalmol Soc. 1999Ophthalmol Soc. 1999 Use non- absorbable sutures - Use non- absorbable sutures - recurrence of recurrence of

stretched scarstretched scar

Reason #7:Reason #7: Scar migration* [Ludwig] Scar migration* [Ludwig]**Speculative - no evidenceSpeculative - no evidence

Audit of Consecutive XTAudit of Consecutive XT LK private pts, 2y to Oct 2005:LK private pts, 2y to Oct 2005: 91 cases of consec XT91 cases of consec XT Av time to XT ~ 8 yAv time to XT ~ 8 y 58/91 : XT surgery by LK58/91 : XT surgery by LK 32 : follow up ≥1 y32 : follow up ≥1 y Number of surgeries: 1- 4Number of surgeries: 1- 4

Median: 1Median: 1 Average:1.3Average:1.3 Botox for consec ET : 4 (10%)Botox for consec ET : 4 (10%) Adjustables: 19 (57 %)Adjustables: 19 (57 %)

These are difficult casesThese are difficult cases Need to make MR function normal or Need to make MR function normal or

XT will recurXT will recur Difficult to dissect out tendons Difficult to dissect out tendons Muscle ‘meat’ can be 20+ mm from limbusMuscle ‘meat’ can be 20+ mm from limbus Adjustables often necessary [57%]Adjustables often necessary [57%] Fat may be presentFat may be present NO surgical tablesNO surgical tables Guide: Early ET ≥ 10 ∆Guide: Early ET ≥ 10 ∆

Pre-op: Range 6 – 66 XT; Av 31XTPost-op: Range 18ET – 45XT; Av 0

2/32: ended up worse! - work in progress

Pre and post op results

-30

-20

-10

0

10

20

30

40

50

60

70

80

0 5 10 15 20 25 30 35

Patient number

<--- Esotropia Exotropia ---->

(_)Pre op

Post op

Post- op results

11 11

7

3

0

2

4

6

8

10

12

Excellent (0-5 ET/XT)

Good (6-10 ET/ XT) Imperfect (11-20ET/ XT)

Poor (>20 ET/ XT)

No. of patients

22/32 ≤ ± 10 ∆

3/32 10% poor result

Amblyopia and XT surgical results

0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

% of patients

No amblyopia

6/12 - 6/36

<6/48

No amblyopia 26.67% 40.00% 26.67% 6.67%

6/12 - 6/36 36.36% 45.45% 9.09% 9.09%

<6/48 50.00% 0.00% 33.33% 16.67%

Excellet good Imperfect Poor

Amblyopia no guide to surgical outcome

Hypermetropia and XT surgery results

0.00%

10.00%

20.00%

30.00%

40.00%

50.00%

60.00%

70.00%

% of patients

<+2.00

+2.00 - +4.00

> +4.00

<+2.00 37.50% 25.00% 18.75% 18.75%

+2.00 - +4.00 20.00% 60.00% 20.00% 0.00%

> +4.00 50.00% 33.33% 16.67% 0.00%

Excellent Good Imperfect Poor

Hyperopia no guide to surgical outcome

Age and XT surgery results

0.00%

5.00%

10.00%

15.00%

20.00%

25.00%

30.00%

35.00%

40.00%

45.00%

50.00%

% of patients

<20

20-40

>40

<20 44.44% 33.33% 22.22% 0.00%

20-40 33.33% 33.33% 20.00% 13.33%

>40 25.00% 37.50% 25.00% 12.50%

Excellent Good Imperfect Poor

Younger pts less likely to get bad results

RESULTS 1RESULTS 1 Gomez De Liano Sanchez et alGomez De Liano Sanchez et al Consecutive exotropia surgery Consecutive exotropia surgery

Arch Soc Esp Oftalmol. 2001 Arch Soc Esp Oftalmol. 2001 Retrospective n= 30Retrospective n= 30 Before surgery, 53% amblyopia, 67% Before surgery, 53% amblyopia, 67%

rotation limitation. rotation limitation. LR Rc OU for < 35 ∆ LR Rc OU for < 35 ∆ Advance 1-2 MR if > 35 ∆Advance 1-2 MR if > 35 ∆ 70%: ≤± 10∆70%: ≤± 10∆ > 50% one surgery. > 50% one surgery.

RESULTS 2RESULTS 2

Donaldson Donaldson MJMJ, , Forrest MPForrest MP, , Gole GAGole GA

Surgical management of consec XTSurgical management of consec XT

J AAPOS. 2004 J AAPOS. 2004 n=59. F/up ≥ 6w [mean 16 mo] n=59. F/up ≥ 6w [mean 16 mo] SSx x : LR Rc, MR adv to original insertion : LR Rc, MR adv to original insertion Time to XT STime to XT Sx mean 14y (4mo-47 y) mean 14y (4mo-47 y) LK 8yLK 8y

Mean preop XT 32 ∆ Mean preop XT 32 ∆ LK 31∆LK 31∆

Result ≤±10∆ : 71% @ final follow-up Result ≤±10∆ : 71% @ final follow-up LK 71%LK 71%

66% : exodrift after surgery - mean 8 ∆66% : exodrift after surgery - mean 8 ∆

Spontaneous consecutive XTSpontaneous consecutive XT

2 cases of spontaneous consecutive XT2 cases of spontaneous consecutive XT 2% of all consecutive XT2% of all consecutive XT High +, amblyopia, cong ETHigh +, amblyopia, cong ET

# 1 : 10 yo F, infantile ET# 1 : 10 yo F, infantile ET XT first noted ~ 2 yoXT first noted ~ 2 yo Now XT 10Now XT 10ΔΔ with V with V R +8.75, L +7.00R +8.75, L +7.00 R amblyopia 6/12R amblyopia 6/12 No surgeryNo surgery

Spontaneous consec XTSpontaneous consec XT

# 2# 2 30 yo F30 yo F Infantile ET Infantile ET ? Age onset XT? Age onset XT RXT 35RXT 35ΔΔ R +7.50, L +4.50R +7.50, L +4.50 R 6/45R 6/45 R Rc/ Rs : RET 7R Rc/ Rs : RET 7ΔΔ

Spontaneous consec XTSpontaneous consec XT Alan Scott : unpublished series n= 19 ET ≤ 20 ∆ Onset ≤ 2y ≥ + 4 DS Amblyopia ≥ 1 line 12/19 : spontaneous consec XT Only 4/19 stayed ET ET usually declined ≥ age 5

“This set you don’t want to touch surgically at an early age”

LK: 70 pts with ET > +6 2003-5 2/70 spontaneous consec XT

SUMMARY - CONSEC XTSUMMARY - CONSEC XT

DifficultDifficult Common in a dedicated strabismus Common in a dedicated strabismus

practicepractice Common in a cong ET populationCommon in a cong ET population Expect 70% to do very wellExpect 70% to do very well Expect 10% not to do very wellExpect 10% not to do very well