40 cases
≥3mo follow up
Retrospective private practice chart review
Kowal L, Marshman W, Sahare P 1



Introduced by Alan Scott in 1979 for adult strabismus
Mechanism :
While muscle is totally paralysed, stretching of this muscle & contracture of active ipsilateral antagonist → new sarcomere density, new L - T curve & new alignment SOME of which persists when paralysis recovers
Kowal L, Marshman W, Sahare P 2


Results – what we used it for

Indications – what it’s good for
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Problems
Kowal L, Marshman W, Sahare P 3

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
77% (n=31) in office Botox most 2.5 – 5 u [thyroid → 20u]
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EMG control
Repeated if no ‘take’ or inadequate result @ Dr’s discretion
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23% (n=9) : intraoperative injection
Kowal L, Marshman W, Sahare P 4

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
Fairly reliable for residual & consecutive ET
Not reliable in Graves’ and XT



Effective as adjunct to surgery in large angle esotropia Tychsen
> 60 ∆ : BMR 6mm + Botox 2.5 to MR
> 75 ∆ : ….. + Botox to both medials
Kowal L, Marshman W, Sahare P 5


Age 3 mo to 80 y (mean 40.5 y)

47% F 53% M
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70% eso 20% hypo 10% exo
70% strab ≥ 6 mo
20% strab ≤ 3 mo
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55% previous strab surgery [n=2]
Kowal L, Marshman W, Sahare P 6

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All ≥ 3 mo follow up
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53% ≥ 6 mo follow up

Unknown selection bias : How different are those with < 3 mo follow up?
Kowal L, Marshman W, Sahare P 7


70% (n=31) Botox to MR

20% (n=8) Botox to IR
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10% (n=4) Botox to LR
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68% (n=27) 5 u

20% (n=8) 2.5 u


5% (n=2) 7.5 u
8% (n=3) ≥ 10 u
Kowal L, Marshman W, Sahare P 8

COMPLICATIONS

Ptosis 15% (n=6)
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Acquired vertical 8% (n=3)
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ALL RECOVERED
Kowal L, Marshman W, Sahare P 9

 N PRE INJ POST INJ %CHANGE


Residual 7 26 ∆ 5 ∆ 59
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Consec 6 32 9 74
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Large 5 64 22 66
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Cong 1 80 0 100 with surgery
Kowal L, Marshman W, Sahare P 10

TABLE 2



DIAGNOSIS N PRE INJ POST INJ CHANGE
ET after RD Sx 2 25 8 75%

ET after Transp 1 18 6 67
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6th n paresis 3 27 9 62
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Neurological ET 2 22 12 47
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All ET 27 36 8 66
Kowal L, Marshman W, Sahare P 11

TABLE 3
DIAGNOSIS N PRE INJ POST INJ CHANGE




Graves’ 6 25 17 36
Iatrogenic vertical 2 15 6 60
ALL HYPO 8 24 15 36
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Residual XT 2 22 35 0
Exotropia 1 35 5 85
Consecutive XT 1 25 14 44
ALL XT 4 26 22 32

AASI 1 32 15 53
Kowal L, Marshman W, Sahare P 12


Retrospective chart analyses not great EBM

NO prospective randomised series on Botox for strabismus

Otis Paul SKI series n > 200 patient – selected randomisation
Low % follow up
ARVO not [yet] accepted by refereed jnl

Carruthers
Smaller prospective series
Kowal L, Marshman W, Sahare P 13


Residual 7 26 ∆ 5 ∆ 59

Consec 6 32 9 74

All ET 27 36 8 66

Reliabilty approaches surgery esp in difficult pts [multiple re-ops] & esp if 2 nd Botox shot ‘allowed’
Kowal L, Marshman W, Sahare P 14

Suggested scenarios for Botox


2 yo cong ET
4 surgeries so far now 45 ∆ ET

R/O +, 6ths, Duanes
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McNeer / Gomez : Bimedial Botox repeated prn
Can it be less reliable than a 5 th surgery?
Kowal L, Marshman W, Sahare P 15

Suggested scenarios for Botox


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25 yo WCF
+ 1.50 won’t wear gls sc L ET 15, ET’ 25

L amblyopia

Consec XT less likely with Botox than surgery
Kowal L, Marshman W, Sahare P 16

CONCLUSIONS
Botox > 20 y experience
NO good studies
Useful for ET esp difficult ET
LK: recommends for Graves’ hypo
Kowal L, Marshman W, Sahare P 17