STRABISMUS REOPERATION : A SECOND CHANCEPRE-OPERATIVE EVALUATION

LIONEL KOWAL

MELBOURNE AUSTRALIA

STRABISMUS REOPERATION : A SECOND CHANCE

Starting points:This will be difficultI need to be careful and

accurate in my evaluationMy pt’s expectations may be

unrealistically high

STRABISMUS REOPERATION : A SECOND CHANCE

PRE-OPERATIVE EVALUATION How did the pt get to this

point? Full exam Surgical plan Patient’s expectations = Dr’s

THE NEED FOR RE-OPERATION

IS IT ANYONE’S FAULT?

CONG ET

NEED FOR RE-OPERATION CAN BE PART OF THE NATURAL HISTORY OF ALIGNMENT SURGERY

PART OF THE NATURAL HISTORY OF ALIGNMENT SURGERY

CIANCIA’S EXTRAORDINARY PERSONAL SERIES OF CONG ET

BMR SOME: OTHER MUSCLES ALSO

WEEK 1: 90% ORTHOTROPIA 5Y: 10% CONSEC XT 15+Y: 30% CONSEC XTFollow up about 50%

NATURAL HISTORY OF SUCCESSFUL ALIGNMENT SURGERY IN CONG ET

THAT AMOUNT OF MEDIAL RECTUS REPOSITIONING REQUIRED FOR ALIGNMENT IN CONG ET WILL, WITH SUBSEQUENT GROWTH OF EYE, MUSCLE, ORBIT

→ REDUCED MR FUNCTION IN 30% → XT NEEDING TREATMENT

NATURAL HISTORY OF SUCCESSFUL ALIGNMENT SURGERY IN CONG ET

SUCCESSFUL HORIZONTAL STRAIGHTENING DOES NOT PRECLUDE SUBSEQUENT DEVPT OF DVD REQUIRING Rx

THE NEED FOR RE-OPERATIONIS IT ANYONE’S FAULT? EXOTROPIAS

ET : MR ALWAYS TIGHT & MR Rc ADDRESSES THE BASIC PROBLEM.

XT DUE TO ‘ABNORMAL BALANCE OF FASCIAL FORCES WITHIN THE ORBITS’

XT : LR NOT ALWAYS TIGHT. LR SURGERY DOESN’T ALWAYS

ADDRESS THE BASIC PROBLEM IN XT → HIGHER LONG TERM FAILURE RATE THAN ET

THE NEED FOR RE-OPERATIONIS IT ANYONE’S FAULT?

SURGERY MECHANICALLY REALIGNS THE EYES

EYES THEN HELD STRAIGHT BY: STABLE MUSCLE- SCLERA UNION LUDWIG: NOT ALWAYS SO NORMAL MUSCLE MECHANICS5mm recess may function better than 7mm recess FUSIONAL VERGENCE – KEEPS ANY

MISALIGNMENT AS A PHORIA

SENSORY FACTORS IN MAINTAINING STRAIGHTNESS

GOOD SENSORY FUSION NEEDED FOR GOOD MOTOR FUSION HIGH AMETROPIA esp high+ → POOR PERIPHERAL FUSION →

SPONT / CONSEC XT MORE COMMON POOR VISION → POOR PERIPH & POOR CENTRAL FUSION →

SPONT XT MORE COMMON

PRE OPERATIVE EVALUATION:HISTORY

REOPERATION FOR DIPLOPIA

ACCURATE HISTORY : HOW TROUBLESOME IS IT?

Diplopia itself Sore neck?

COMMONLY MISSED BARRIERS TO FUSION:** TORSION ** ANISEIKONIA

PREDISPOSITION TO DIPLOPIA

REALIGNMENT IN PT WITHOUT DIPLOPIA:

TESTS WITH probably GOOD Pos Pred Value FOR POST OP SINGLE VISION

1. CAN THE PT RECALL SINGLE VISION WHEN PERFECTLY ALIGNED?

2. PRISM & PAT3. Botox testing [UK]

PRE OPERATIVE EVALUAION:HISTORY TIME COURSE OF STRAB

Recurrence / overcorrection seen early has different etiology / Rx / expectations to that seen late

Accurate history supported by Family Album Test important

PRE OPERATIVE EVALUAION:HISTORY TIME COURSE OF STRAB

CASE 32 YO [XT], WORSE IF TIRED. ET & THICK GLS WHEN YOUNG RECALLS PARENTS’ / DOCTORS’

CONCERN ABOUT ADDUCTION IN Week 1 AFTER BMR age 7.

NOW : LMR UA > RMR UAManifest Refraction + 2 DS OU. Uncorrected vision 20/20.

PRE OPERATIVE EVALUATION

HISTORY STRETCHED SCAR OF LUDWIG

POOR SCAR MATURATION / ILLNESS / MALNUTRITION INTERFERES WITH INTEGRITY OF MUSCLE/ SCLERA UNION → STRETCHED SCAR

LOOKS LIKE MUSCLE HAS SLIPPED WITHIN ITS TENDON

POTENTIALLY HAZARDOUS DURING SURGERY [‘SNAP!’]

PRE OPERATIVE EVALUATION

HISTORY STRETCHED SCAR OF LUDWIG

ONE CAUSE OF CONSEC XT AFTER BMR EXAMINE EASILY VISIBLE SURGICAL

SCARS ON SKIN - ?THIN ATROPHIC SCARS MAY REFLECT MUSCLE / SCLERA UNION ? XS STRETCHMARKS

NON-ABSORBABLE SUTURES FOR REOP

PRE OPERATIVE EVALUATION:THE PLAN

40 yo WCF consec XTNo baby photos – looked too bad4 surgeries ages 2,8,12,13 variously ET /XTNever had diplopia‘perfectly’ aligned ages 13-291st pregnancy @ 29: XT develops

PRE OPERATIVE EVALUATION:THE PLAN

40 yo WCF consec XT

BCVA +3 etc 20/30+, +4 etc 20/40XT 30Δ, XT’ 40ΔSmooth pursuit asymmetryRMR UA > LMR UAScars all H recti

PRE OPERATIVE EVALUATION:THE PLAN

40 yo WCF consec XT

EXPECTATIONS? Over Rc MR OU ? Stretched scarSURGICAL PLANExplore MR OU with great careMake MR function normalEarly ET desirable = best result2nd best result : larger early ET

PRE OPERATIVE EVALUATION: THE EXAMINATION

DO AN ACCURATE / COMPLETE STRAB EXAM

CHECK GLS FOR Δ & PALs NEUTRALISE STRAB WITH Δ &

CHECK SENSORY RESPONSE

PRE OPERATIVE EVALUATION: THE EXAMINATION : FACTORS THAT MAY MODIFY THE SURGICAL PLAN

IF LATERAL / VERTICAL INCOMITANCES LOOK FOR ALL THE USUAL ASSOCIATED FACTORS TO MAKE SURE IT ALL ‘FITS’

PRE OPERATIVE EVALUATION: THE EXAMINATION : FACTORS THAT MAY MODIFY THE SURGICAL PLAN

VERSION / DUCTION DEFICITS / OVERACTIONS

IS A DEFICIT DUE TO UA OR RESTRICTION? MR UA looks like tight LR FORCEPS TESTING – IS DUCTION DEFICIT

DUE TO WEAKNESS OR RESTRICTION? Rc LR when the MR is weak → result won’t

last

PRE OPERATIVE EVALUATION:SPECIAL AND FANCY TESTS

RISK OF ISCHAEMIANEED TO OPERATE ON ADJACENT

MUSCLES

NORMAL IRIS ANGIOGRAM ENCOURAGING

PRE OPERATIVE EVALUATION:SPECIAL AND FANCY TESTS

WHEN TO SCAN

EVOLVING

IF THINGS DON’T ‘FIT’

PRE OPERATIVE EVALUATION

Reops are difficult for patient and Dr Careful complete assessment Careful pt education 2nd opinions sensible for difficult

cases Starting with humility is easier than

having it thrust on you