EXOTROPIA EXOTROPIA DR LIONEL KOWAL FRANZCO FRACS MELBOURNE

EXOTROPIA

EXOTROPIA DR. LIONEL KOWAL FRANZCO, FRACS MELBOURNE, AUSTRALIA

EXOTROPIA ETIOLOGY OF EXODEVIATIONS NOT A MIRROR IMAGE OF ESOTROPIA BALANCE OF FASCIAL FORCES IN ORBIT HARD TO QUANTIFY ANESTHESIA POORLY UNDERSTOOD ANATOMICAL FACTORS ORBITAL SHAPE LR TENSION MAY BE NORMAL ET: MR ALWAYS HIGH [ROSENBAUM] LESS RELIABLE SURGICAL RESULTS Kowal

EXOTROPIA ETIOLOGY OF EXODEVIATIONS NEED TO EXPLAIN ALL OF: CAUCASIAN : ET > XT ASIA : XT > ET JAPAN : CONV INSUFF COMMONEST XT POSSIBLE REASONS / ASSOCIATIONS > 25% CAUCASIAN NEONATES > +4 > 60% ADULT ASIANS MYOPIC ORBITAL SHAPE IN ASIANS Kowal

EXOTROPIA ETIOLOGY OF EXODEVIATIONS MOTOR FUSION ’PROTECTS’ AGAINST XT REDUCED MF → MORE PRONE TO XT S: VA ANY REASON e. g. AMBLYOPIA M: CYCLOVERTICAL ANOMALY MF > EXO : PHORIA MF = EXO: I/MITT TROPIA MF < EXO: CONSTANT TROPIA Kowal

EXOTROPIA ‘STANDARD’ XT : D > N – WHY? MF : N>D - PROVIDES MORE ‘PROTECTION’ AGAINST NEAR XT & OTHER PROXIMAL MECHANISMS ARE ADDITIVE (TPF) Kowal

EXOTROPIA KUSHNER ARCHIVES 2 -4/98, 2/99 NEW MINIMUM STANDARDS FOR EVALUATION OF XT TARGET ANGLE & SURGICAL DOSE DEPENDENT ON SEVERAL SUBTLE ASPECTS OF EXAMINATION Kowal

EXOTROPIA KUSHNER SCHEME 1 A. 20 ft EXAM & B. OUTSIDE TARGET EXAM & C. PATCH FOR 1 HOUR B, C : ½ PTS - XT ANGLE AUGMENTS LARGER SURGICAL DOSE Kowal

EXOTROPIA KUSHNER SCHEME 2 ? DIVERGENCE XS (DX) C : PATCH 1 HOUR 80% of DX BECOME D = N →Simulated DX DX PERSISTS: CHECK WITH +3 FOR N TRUE HIGH ACA / TRUE DX Kowal

EXOTROPIA OTHER EXOTROPIAS 1. DXD 2. CONSECUTIVE XT 3. INFANTILE XT 4. CONVERGENCE INSUFFICIENCY 5. NEUROLOGICAL XT Kowal

EXOTROPIA DXD [RAAB, WILSON] DISSOCIATED EXO DEVIATION LOOKS LIKE ‘UNILATERAL’ XT E. G. : RIGHT FIXATION : L EXO LEFT FIXATION : NO EXO Exclude: Uncorrected + LE & RMR UA “COUSIN” OF D. V. D ? SIMILAR NYSTAG BLOCKING MECHANISMS • ALL : Smooth Pursuit Asymm / CONGENITAL STRAB • MANY : PREVIOUS LR RESECT Kowal

EXOTROPIA CONSECUTIVE XT CIANCIA : 390 CASES CONG ET WEEK 1 : 90% ORTHO 10 -28 y follow up : 20% > 10∆ XT ** THAT AMOUNT OF MR RECESS → SUCCESSFUL EARLY ALIGNMENT EVENTUALLY → CONSEC XT IN 20% Kowal

EXOTROPIA CONSECUTIVE XT 1. MOTOR FACTORS SCAR REMODELLING / MIGRATION [LUDWIG] ALPHABET PATTERNS esp. A SUBSEQUENT GLOBE / ORBITAL GROWTH 2. SENSORY FACTORS MORE COMMON WITH HIGH + POOR PERIPHERAL FUSION Kowal

EXOTROPIA INFANTILE XT • MIRROR IMAGE CONG ET • EARLY ONSET “REGULAR” XT • SYSTEMIC DISEASE esp. CNS Kowal

EXOTROPIA CONVERGENCE INSUFFICENCY MULTIPLE DIAGNOSTIC CRITERIA REMOTE NPC X’ XT N > D REDUCED NEAR BOFR MULTIPLE CLINICAL TYPES CHILDHOOD ADOLESCENT SENILE NEUROLOGICAL AWAITS RECLASSIFICATION AND IMPROVED UNDERSTANDING Kowal

EXOTROPIA NEUROLOGICAL XT ‘BREAKDOWN OF PRE-EXISTING PHORIA’ DANGEROUS DIAGNOSIS • I. N. O. • FIELD DEFECT all types • POOR MOTOR FUSION TBI, PARKINSON’S • +VE NEURONAL ANTIBODY • C. P. E. O. • MYESTHENIA Kowal

EXOTROPIA CORE SLIDE: DECIDING ON THRESHOLD FOR TREATMENT DELICATE / CAREFUL BALANCE BETWEEN : • NATURAL HISTORY • ADVANTAGES OF XT • DISABILITY OF XT [DISABILITY ‘SCORE’] & • ADVANTAGES OF RX • MORBIDITY OF RX Kowal

EXOTROPIA SYMPTOMS SCORE UCLA : HOME 1. XT, EX’=O MANIFEST TIRED , INATTENTIVE 2. XT < 5/d 3. XT > 5/d EX’=O 4. ONLY OCCASIONALLY STRAIGHT Kowal

EXOTROPIA SYMPTOMS SCORE UCLA : OFFICE 1. COVER TEST TO BREAK→RAPID RECOVERY 2. RECOVERY AFTER BLINKING 3. BREAKS SPONTANEOUSLY Kowal

EXOTROPIA MELBOURNE XT SYMPTOM SCORE 1. POTS % OF TIME STRABISMIC ______x 10% = /10 2. M. E. C. /3 3. DIPLOPIA /2 4. OTHERS NOTICE IT /2 5. OTHER _______ /2 _____ /17+ USUAL THRESHOLD 7 -8 Kowal

EXOTROPIA OTHER FACTORS TO REACH THRESHOLD • GLARE SENSITIVITY • ↓ DISTANCE STEREO • BOTHERSOME AWARENESS OF XT [ADULTS] • BINOCULAR BLUR Kowal

EXOTROPIA OTHER FACTORS TO REACH THRESHOLD BINOCULAR BLUR [La Roche] 12 y old : I/MITT BLUR 2 y ago : I/MITT M. E. C. & DIPLOPIA 5 y ago : I/MITT MISALIGNMENT BEO : 20/25 EITHER EYE : 20/20 NOW SYMPTOMS OF Xs ACCOMMODATION 2 y ago : SYMPTOMS OF EXO Kowal

EXOTROPIA CONCLUSION • XT COMPLEX • MORE TRAPS • MORE DIFFICULT TO EVALUATE • THRESHOLD FOR RX : DEPENDENT ON SYMPTOMS Kowal

EXOTROPIA VERTICALS IN XT E. G. XT 30, LH 6 EX’=0 8 CYCLOVERTICAL MUSCLES Vertical Fusion Range ± <3∆ → FRAGILE BALANCE c. f. HORIZ FR WITH LITTLE / NO ROOM FOR ERROR 15° HORIZONTAL MISALIGNMENT : VERTICAL IMBALANCE NO SURPRISE Kowal

EXOTROPIA THRESHOLD FOR TREATMENT SYMPTOMS DEFINE THE NEED TO RX SIGNS DEFINE HOW TO RX Kowal