Analysis of Results of Various Surgeries on the Superior Oblique KOWAL L MAHINDRAKAR A RVEEH, MELBOURNE

Preamble Superior oblique surgeries are infrequent in Anglo-American strabismus Reputation for being difficult and prone to complications AIM: To examine the results of various superior oblique surgeries (single surgeon)

Methods Records of 27 patients who had SO surgeries* and who were seen between 2004 -08 were analysed *some had their surgeries outside this period

1. Superior oblique paresis / palsy SOP Diagnostic groups 1. Superior oblique paresis / palsy SOP 2. Hypotropia 3. Brown’s 4. A pattern

Typical Pre-op case

RIO +, RSO -, RIR - Typical changes of ‘chronic’ true SOP. RSO UA, RIO OA, and RIR UA from the tight SR seen after ‘chronic hypertropia’

SOP Full tendon width strengthening operation considered if: Intra- op FDT shows significant unequivocal floppiness [‘..just keeps going’] Usually: Coronal scan shows atrophy Usual operation: advancement / plication @ insertion till mild Brown’s created [can elevate 6 o’clock limbus ~3mm above the intercanthal horizon]

Results – 4 pts with SO plication 2 unilateral cong. SOP 1 bilateral cong. SOP 1 bilateral acquired SOP due to post. fossa lesion

Unilateral Cong. SOP n=2 Both had SO plication and Parks’ IO recess One required re-plication Both have improved AHP 3 yrs later One has good ROSV with 100” stereo

Bilateral cong SOP n=1 Bilateral SO plication Has large ROSV at 1 year Torsion corrected from 10° excyclo to < 5° incyclo Minimal residual hypertropia in R gaze (pre-op 20∆); none in L gaze (pre-op 12∆)

Bilateral SOP 2ary to post. fossa lesion n=1 Unilateral plication + bilateral IO recession + vertical R-R OU [!] 13 years follow-up: good ROSV SO plication corrected 10° of excyclotorsion (8° residual)

In selected cases, a reliable and safe operation Plication for SOP In selected cases, a reliable and safe operation

2. Hypotropia Diagnostic groups 1. Superior oblique paresis / palsy SOP 2. Hypotropia 3. Brown’s 4. A pattern

Hypotropia n=4 1-2y follow-up n = 2 Tenotomy corrected hypo (7∆ and 15∆) improved A pattern from 25 to 12 ∆ in one pt.

Hypotropia n=4 1-2y follow-up n =2: Recession – [posterior] transposition to 13mm from limbus & 2mm nasal to SR (Souza Dias) corrected hypo (15 and 14∆) improved A pattern from 25 ∆ to < 5∆

3. Brown’s Diagnostic groups 1. Superior oblique paresis / palsy SOP 2. Hypotropia 3. Brown’s 4. A pattern

Results - Brown’s 6 patients Spacer, Tenotomy, Recession 1-2 years follow-up

Results - Brown’s Spacer → no improvement (1 pt.) FDT was negative SO tenotomy + IO recession → no improvement (1 pt.) SO tenotomy + IO Rc + LR Rc → Good range of movement (1pt.)

Results - Brown’s SO tenotomy + IO rec. + other SR faden → improved appearance (1 pt.) SO spacer (later removed) + IO rec. + other SR faden → No AHP; large ROSV (1 pt.) SO recession ~12mm → corrected AHP (1 pt.)

Brown’s These results are not as good as published series Pathology may vary 2ary effects [eg tight verticals] may come to dominate the clinical picture and obscure the original pathology

4. A pattern Diagnostic groups 1. Superior oblique paresis / palsy SOP 2. Hypotropia 3. Brown’s 4. A pattern

A pattern n=14 10 : Partial tendon weakening operation : bilateral SO posterior tenectomy [SOPT] 4 : full tendon width weakening operation 1 full tendon width tenotomy 1 spacer 2 recession – transposition 1-3 y follow-up 10 had a PARTIAL tendon width operation, the SO PT operation

Posterior tenectomy SO

Posterior tenectomy NOTE: WIDE SCATTER OF RESULTS OVER HALF HAVE AN UNDERCORRECTION! From Souza Dias & Praeto Diaz

Posterior tenectomy NOTE: WIDE SCATTER OF RESULTS OVER HALF HAVE AN UNDERCORRECTION! From Souza Dias & Praeto Diaz

SO Post. Tenectomy n=10 1-4 years follow-up 2/10 patients improved completely Max. correction 20 ∆

SO Post. tenectomy 5/10 had partial or complete correction 3/10 patients had partial correction Improvement varied from 10 – 12 ∆ 5/10 had partial or complete correction

SO Post. tenectomy 3 patients had no improvement 2 patients : A pattern worse

‘A’ pattern – complete tenotomy n=1 2 years follow-up ‘A’ pattern improved from 25 ∆ to 12 ∆ Also corrected hypotropia of 7 ∆

‘A’ Pattern – SO spacer n=1 1 year follow-up AHP resolved

‘A’ Pattern Recession – Transposition n=2 One had correction of 70 ∆ !! One had improvement in ‘A’ from 25 ∆ to < 5 ∆ + correction of 14 ∆ hypo

Recession - transposition FAIRLY TIGHT RESULTS

SO surgeries One abandoned as no tendon was found

Complications One spacer: chronic inflammation and recurrence of Brown’s after temporary improvement No lid problems

Conclusions Palsy → plication reliable [if well selected] Hypotropia → good results from tenotomy, recess / transpose ‘A’ pattern → Full tendon width procedure better than PTSO PTSO → not reliable for ‘A’ pattern Brown’s → mixed results

Pre-op (Centofanti Rec- trans)

Pre-op (dula – tenotomy)

Pre-op (dula tenotomy)