This 5 year old girl was injured with a sharp
object which penetrated the inferior orbit
between the lower lid and the globe since 1
year. The lower lid had an injury near the outer
canthus, the lower fornix and the bulbar
conjunctiva were also had an injuries which were
sutured at the day of trauma. Three days later,
the mother noticed that the Rt eye is
significantly higher. Motility examination was
shown here together with a short video for the
child.
See video of this patient
Fat Adherence Syndrome
Fat adherence is a
restrictive form of strabismus occurring
after periocular surgery or accidental
trauma.
Normally, Tenon’s
capsule and muscle sleeve act as an elastic
barrier separating the globe from the
surrounding orbital fat. Fat adherence is
caused by violation of the posterior Tenon’s
capsule, allowing exposure and manipulation
of extraconal fat and fascia, which produces
an adhesion of these tissues to the sclera.
Because the septae within the extraconal fat
connect to the periorbita, fibrosis
associated with fat adherence can extend
from the orbital bone to the sclera. In
severe cases, the eye is virtually scarred
to the orbital bone, immobilizing ocular
rotations. Violation of the muscle sleeve
can also result in fat adherence to a rectus
muscle causing a tight muscle.
Fat adherence is
difficult to surgically correct, as
recurrence of fat adherence after removal of
adhesions is very common. Once Tenon’s
capsule is violated and a scar established,
it is almost impossible to reestablish the
delicate fascial barrier to prevent
recurrence of scarring. Teflon or silicone
sheaths have been used as an artificial
barrier, but they become encapsulated in
scar and often make the restriction worse.
Amniotic membrane transplantation has been
used to create a barrier separating
periocular fat from the sclera, but the
technique is difficult. Surgical correction
of fat adherence consists of releasing the
scar by dissecting close to sclera and
removing the adhesions without repenetrating
the orbital fat. (Perform forced ductions
after freeing adhesions to evaluate
improvement of the restriction.) Dissect
carefully with direct visualization, as
posterior dissections can be dangerous.
Cases of inadvertent optic nerve transection
have occurred, although they are rarely
reported. If fat and scar are adherent to a
rectus muscle, remove a small amount of the
anterior scar, then recess the tight muscle
en bloc with the scar rather than trying to
dissect all the scar off the muscle. Avoid
extensive dissection of scar off the muscle,
as this usually results in further fat
manipulation and worsening of the adherence.
Medical treatment with mitomycin-C has not
been effective in reducing postoperative
fibrosis and may even increase scarring.
Injection of peribulbar corticosteroids also
fails to prevent postoperative scarring. The
best treatment for fat adherence syndrome is
prevention: avoid penetration of posterior
Tenon’s capsule during the initial surgery.
During strabismus surgery, perform minimal
dissection of muscle fascia and, when
dissecting, dissect close to the muscle to
stay away from surrounding orbital fat. If
Tenon’s capsule is inadvertently torn so fat
is
exposed, cover the
exposed fat by repairing the Tenon’s tear
with 7-0 vicryl suture.
الموقع المصري للحول
وامراض الجهاز الحركي للعين
The Egyptian Site of
Strabismus & Oculomotor Disorders
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