surgeries Flashcards
SO tuck
strengthing
- achieves the same result as resection without the need to
detach the muscle and thus preserves the blood supply. It consists of folding the
muscle over and suturing it in place to shorten it. It also possesses the advantage of
being potentially reversible by dividing the fixing sutures. However, some surgeons
feel it is not quite as effective as resection and so surgical amounts may need to be
increased.
-ckmplication: can cause iatrogenic browns
Harado-Ito
. In fourth nerve palsy where excyclorotation is the main finding, 1/3 SO fibres can be transposed inferiorly and laterally towards the LR to help augment incyclorotation , because anterior fibres control torsion.
Knapp
LR + MR moved to SR
Inverse Knapp
LR + MR attached to IR
Yokoyama
The LR and SR muscle bellies are
sutured together to reform the muscle cone without involving the sclera or splitting
the muscles with good results .
Heavy Eye syndrome or myopic fixus is a condition where there is progressive
development of hypotropia and esotropia in a highly myopic eye (Fig. 12.10). It is
thought that the large globe prolapses between the SR and the LR displacing them
nasally and inferiorly respectively. The loop myopexy procedure was first described
by Yokoyama for the treatment of this condition. The LR and SR muscle bellies are
sutured together to reform the muscle cone without involving the sclera or splitting
the muscles with good results .
silicone band myoplexy
Silicone band passed joinign the LR and SR via scleral tunnel and tightened to bring two muscles together
myopic eso
why would you do IR instead of SR in 4th
IR becuase greatest problem on downgaze
disinsertion / myectomy
- weakening
Myectomy is the process of disinserting a muscle that is allowed to retract into
its capsule and not attached at a specific point on the sclera. It is only really routinely used for Inferior oblique weakening procedures. Rarely, a LR myectomy is
performed in third nerve palsy where the muscle is attached to the periosteum.
Humelshiem
where the SR and IR are cut and the lateral halves are moved towards the LR and attached to the sclera right next to the upper and lower poles.
Jensens
-muscle hook used to splt muscle equally in two halves
-suture looped around lateral half of SR and anterior half of LR, and lateral half of IR and inferior half of LR!
- no disinsertion of muscle so reduced ASI
hang-back recession
-weakening
The muscle is disinserted from its original attachment and placed posteriorly by
a pre determined amount. It may be sutured directly to the sclera or anchored to the
original insertion in a hang back fashion. Hang back recession has the advantage of
a lower rate of scleral perforation as the suturing is carried out anteriorly with better
access and visibility
myotomy
-weakening
Myotomy is the weakening of a muscle by partial division of the muscle fibres
or removing a portion of the tendon. It tends to have a non-predictable effect and is
not commonly used.
Fadens
-weakning
The muscle is fixed to the sclera back on the equator. As a result, the lever arm
is shortened with consequent reduced force generation but only when the muscle is
used. There is no effect in primary position but a reduction in movement in the
direction of action of the muscle. This can be used very effectively in incomitant
strabismus where there is a deviation in particular direction of gaze but none in
primary gaze
anterior transposition of inferior oblique
The inferior oblique is an elevator of the eye. However, in the treatment of DVD and
fourth nerve palsy, it can be converted into an anti-elevator by changing its course.
The muscle is detached near its insertion and reattached just lateral to the IR at
the same level as its tendon
complications sx
- globe perforation
-lost muscle
-slipped muslce afterwards
-infection
