Inferior Oblique Weakening By Myectomy Versus Inferior
Oblique Muscle Recession Dr Sudhir Singh
Consultant & H.O.D
JW.Global Hospital & Research Centre
Mount Abu
The inferior oblique may be weakened effectively by
recession, disinsertion, or myectomy, disrupting the
muscle continuity between Lockwood's ligament and
the muscle's insertion. But recession and myectomy
are most commonly performed procedures world wide.
It
is widely reported that both myectomies and
recessions procedures of inferior oblique muscles
result in a self-grading operation, so that the
greater the preoperative hyper deviation, the larger
the correction obtained postoperatively
postoperatively.1,2,3,4Both
surgical procedures are effective, so that good
primary position alignment can achieved
Inferior
Oblique Muscle Myectomy
Group
group
Inferior
Oblique Muscle Recession Group
1.T Shipman and J Burke
16 : repoted that the average reduction of
the hyperdeviation in the myectomy group at
12 months postoperatively in primary
position was
14
.
2.Toosi and Von Noorden11 found a mean
reduction of 11.9
of
hyper deviation in primary position and
relatively little difference between the
alignment in primary position and in the
field of action of the inferior oblique or
superior oblique muscles.
3. Helveston and Haldi12similarly
described a greater reduction of 20
of
hyper deviation in the field of action of the
inferior oblique muscle from weakening a
single inferior oblique muscle.
4.Davis G, McNeer KW, Spencer RF2
Reported that distal myectomy is simple,
quick, predictable, and devoid of
significant complications. To affirm this,
130 myectomies performed in 81 patients were
reviewed. The procedure was satisfactory,
although 5% had a postoperative residual
overaction, and 3% had a residual
underaction. No significant complications,
such as the "adherence syndrome," were
observed.
1.Parks: found inferior
oblique muscle recession to be the most
effective procedure. He observed a
persistent inferior oblique muscle
overaction in 37% of patients and inferior
oblique muscle underaction in 8% of patients
after an inferior oblique muscle myectomy,
and 13% incidence of inferior oblique muscle
adhesive syndrome when the myectomy was
performed at the inferior oblique muscle
insertion.
2.Cooper and Sandall7 : found that a measured
recession will decrease the hyperdeviation
by 6.88
∆
in primary position and by 12.3∆
in the field of action of the overacting
inferior oblique muscle.
3. T Shipman and J Burke
16 : a recession reduced
the hyperdeviation by a median of 8 in
primary position and by 16 in contralateral
gaze
4. Kutschke and Scott3
:stated that a reduction of 6.9
PD in
primary position and 15.6 in contralateral
gaze.
5 Mittleman and Folk13
reported a decrease of 9
PD
from a 1012 mm measured recession.
How to perform
Inferior oblique muscle recession ? Inferior oblique muscle recession step by step
approach
An inferotemporal conjunctival fornix incision was
made
the conjunctiva and tenons were opened separately
in layers.
The inferior oblique muscle was identified and
hooked under direct vision.
The inferior oblique was cleared of its
surrounding inter muscular septa from its insertion
to near the temporal border of the inferior rectus
muscle.
The inferior oblique muscle was clamped adjacent
to its insertion and disinserted from the globe
between the artery clamp and its insertion.
For an, a double-armed 6-0 vicryl suture was then
passed through the muscle adjacent to the artery
clamp with lock-bites at either pole.
The two ends of the 60 vicryl suture were then
passed through scleral tunnels 23 mm apart with the
anterior suture inserted 3 mm posteriorly and 2.5 mm
lateral to the temporal pole of the inferior rectus
muscle.
The conjunctiva and tenons were then closed in
separate layers using interrupted 8-0 vicryl
sutures.
How to perform
Inferior oblique muscle myectomy
? Inferior oblique muscle myectomy
step by step approach
Inferior oblique muscle myectomy
An inferotemporal conjunctival fornix incision was
made
the conjunctiva and tenons were opened separately
in layers.
The inferior oblique muscle was identified and
hooked under direct vision.
The inferior oblique was cleared of its
surrounding intermuscular septa from its insertion
to near the temporal border of the inferior rectus
muscle.
The inferior oblique muscle was clamped adjacent
to its insertion and disinserted from the globe
between the artery clamp and its insertion.
a second artery clamp was used to clamp the muscle
near the temporal border of the inferior rectus
muscle.
The muscle was transected adjacent and temporal to
the second clamp.
Haemostasis was achieved prior to removing the
clamp.
The inferior oblique muscle was then observed and
its retraction facilitated into tenons capsule
overlying the inferior rectus muscle so that its
stump was no longer in direct contact with the
sclera.
The conjunctiva and tenons were then closed in
separate layers using interrupted 8-0 vicryl
sutures.
Complications of inferior oblique weakening
persistent over action,
operation on the wrong muscle,
adherence syndrome.
Note: The adherence syndrome is not related to the
myectomy procedure specifically but is probably
related to (or caused by) fat rupture with
hemorrhage, which may accompany any type of inferior
oblique weakening. The adherence syndrome can be
avoided by careful surgical technique.
References
1.
Harcourt B, Almond S, Freedman H. The efficacy of
inferior oblique myectomy operations. In: Mein J,
Moore S (eds). Orthoptics, Research and Practice.
Transactions of the Fourth International Orthoptic
Congress, 1979, Berne. Kimpton: London, 1981, pp.
2023.
2. Davis G, McNeer KW, Spencer RF. Myectomy of the
inferior muscle. Arch Ophthalmol 1986; 104: 855858.
| PubMed |
3. Kutschke PJ, Scott WE. The effect of inferior
oblique muscle recession in the treatment of
unilateral superior oblique palsy. Am Orthoptic J
1994; 44: 98102.
4. Morad Y, Weinstock VM, Kraft SP. Outcome of
inferior oblique recession with or without vertical
rectus recession for unilateral superior oblique
paresis. Binocular Vision 2001; 16: 2327.
5. Reynolds JD, Biglan AW, Hiles DA. Congenital
superior oblique palsy in infants. Arch Ophthalmol
1984; 102: 15031505. | PubMed |
6. Costenbader FD, Kertesz E. Relaxing procedures of
the inferior obliquea comparative study. Am J
Ophthalmol 1964; 57: 276280. | PubMed |
7. Cooper EL, Sandall GS. Recession versus free
myotomy at the insertion of the inferior oblique
muscle. J Pediatr Ophthalmol 1969; 6: 610.
8. Parks MM. The weakening surgical procedures for
eliminating overaction of the inferior oblique
muscle. Am J Ophthalmol 1972; 73: 107122. | PubMed
|
9. Parks MM. Causes of the Adhesive Syndrome.
Symposium on strabismus. Transactions of the New
Orleans Academy of Ophthalmology. The C.V. Mosby
Company: St. Louis, 1978, pp 269279.
10. Doughty DD, Lenarson LW, Scott WE. A graphic
portrayal of versions. Perspect Ophthalmol 1978; 2:
5559.
11. Toosi SH, Von Noorden GK. Effect of isolated
inferior oblique muscle myectomy in the management
of superior oblique muscle palsy. Am J Ophthalmol
1979; 88: 602608. | PubMed |
12. Helveston EM, Haldi BA. Surgical weakening of
the inferior oblique. Int Ophthalmol Clin 1976; 16:
113. | PubMed |
13. Mittleman D, Folk ER. The evaluation and
treatment of superior oblique muscle palsy. Trans Am
Acad Ophthalmol Otolaryngol 1976; 81: 893898. |
PubMed |
14. Del Monte M, Parks MM. Denervation and
extirpation of the inferior oblique an improved
weakening procedure for marked overaction.
Ophthalmology 1983; 90: 11781183. | PubMed |
15. Gonzalez C. Discussion of denervation and
extirpation of the inferior oblique. Ophthalmology
1983; 90: 11841185.
16. T Shipman and J Burke.Unilateral inferior
oblique muscle myectomy and recession in the
treatment of inferior oblique muscle overaction: a
longitudinal study .Eye (2003) 17, 10131018.
