Transcript AAPOS poster 2006

AAPOS poster 2006
Lateral Orbitotomy in the Management of Challenging Exotropia
Yahalom C (1), Mc Nab A (2), Ben Simon G (2), Kowal L (2).
1-Hadassah University Hospital, Jerusalem. Israel.
2-Royal Victorian Eye and Ear Hospital, Melbourne, Australia
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Introduction: The surgical management of recurrent exotropia (like the one seen following third nerve palsy and other cases with unwanted overactivity of the
lateral rectus), that resists treatment by standard surgical techniques, is one of the most difficult problems facing the strabismus surgeon. The lateral rectus
muscle often keeps pulling the eye back to exotropia following surgery, and further surgical procedures in this muscle become very hard.
Purpose: We present an “un-orthodox” surgical approach, to reach the posterior segment of the lateral rectus through a lateral orbitotomy, to manage these
difficult cases of recurrent exotropia.
Methods: A review of the records of two patients with recurrent exotropia, following standard surgery was done.
Patient number one (N1) had an exotropia following retinal detachment repair, with failed multiple re-operations/explorations on his right lateral rectus (LR)
which was super-glued to the globe due to extensive scarring (not feasible dissection from sclera). A lateral orbitotomy 1 was performed with lengthening of the
posterior segment of the LR with a temporal fascia spacer.
Patient number 2 (N2) had a recurrent exotropia after a complete third nerve palsy. He underwent several surgeries to weaken the LR, including a failed trial to
suturing LR to the orbital wall 2,3,4(due to shortened muscle after repeated surgeries), and an excision of anterior 10mm of the muscle 5 with myochol injection
to the remaining posterior muscle. Two months following the surgery the eye was again 50 PD exotropic. An MRI showed reattachment of lateral rectus stump
to the sclera near the level of the equator. Finally, we performed a posterior excision of LR remnants via a lateral orbitotomy.
Lateral Orbitotomy technique: A skin incision is made in the lateral canthal area, soft tissue is spread out down to the periosteum of the lateral orbital wall. A
vertical incision is made in the lateral orbital rim periosteum, with peeling of this layer. The bone is cut using a saw superior to the level of the zygomatic arch
and take off at the level of Whitnall's tubercle. The lateral wall is removed and kept in moist gauze. The periorbita is incised at the level of the lateral rectus
muscle, the LR is lifted on a squint hook.
At the end of surgery the periorbita is sutured, the bone is positioned back in place and sutured to the wall. The periosteal lining is re-sutured.
Results: Both of the patients achieved satisfactory ocular alignment following surgery. These results were stable for 4 months in patient N1, and 2 years in
patient N2. No mayor complications occurred. Any residual XT?/???
Conclusion: Lateral orbitotomy for posterior lengthening/extirpation of lateral rectus in resistant exotropia, when a standard anterior approach for surgery is not
feasible after repeated surgery on LR, is a safe and effective surgical procedure for restoring ocular alignment in persistent exodeviation.
References:
1-Arai H et al. Lateral approach to intraorbital lesions: anatomic and surgical considerations. Neurosurgery
1996;39(6):1157-1163.
2-Velez F, Thacker N, Britt M, Alcorn D, Foster R, Rosenbaum A. Rectus muscle orbital wall fixation: a reversible
profound weakening procedure.
J AAPOS. 2004 Oct;8(5):473-80
3-Morad Y, Kowal L, Scott A. Lateral rectus muscle disinsertion and reattachment to the lateral orbital wall. BJO
2005;89:983-985.
4-Salazar-Leon JA, Ramirez-Ortiz MA, Salas-Vargas M. The surgical correction of paralytic strabismus using fascia lata.
J Pediatr Ophthalmol Strabismus 1998;35:27-32.
5-Sato M, Maeda M, Ohmura T, et al. Myectomy of lateral rectus muscle for third nerve palsy. Jpn J Ophthalmol
2000;44:555-558.
Lateral Orbitotomy in the Management of Challenging Exotropia
Yahalom C (1), Mc Nab A (2), Ben Simon G (2), Kowal L (2).
Introduction: The surgical management of recurrent exotropia
(like the one seen following third nerve palsy and other cases
with unwanted overactivity of the lateral rectus), that resists
treatment by standard surgical techniques, is one of the most
difficult problems facing the strabismus surgeon. The lateral
rectus muscle often keeps pulling the eye back to exotropia
following surgery, and further surgical procedures in this muscle
become very hard.
1-Hadassah University Hospital, Jerusalem. Israel.
2-Royal Victorian Eye and Ear Hospital, Melbourne, Australia
Purpose: We present an “un-orthodox”
surgical approach, to reach the posterior
segment of the lateral rectus through a
lateral orbitotomy, to manage these difficult
cases of recurrent exotropia.
Fig.2: LR muscle
exposure through
lateral orbitotomy
Results: Both of the patients achieved
satisfactory ocular alignment following
surgery. These results were stable for 8
months in patient N1, and 2 years in patient
N2. No mayor complications occurred.
Patient N1has a small residual XT
Fig.3: Patient N1 (post-op)
Methods: A review of the records of two patients with recurrent exotropia, following standard surgery was done .
Patient number one (N1) had an exotropia following retinal detachment repair, with failed multiple re-operations/explorations on
his right lateral rectus (LR) which was super-glued to the globe due to extensive scarring (not feasible dissection from sclera). A
lateral orbitotomy 1 was performed with lengthening of the posterior segment of the LR with a temporal fascia spacer.
Patient number 2 (N2) had a recurrent exotropia after a complete third nerve palsy. He underwent several surgeries to weaken the
LR, including a failed trial to suturing LR to the orbital wall 2,3,4(due to shortened muscle after repeated surgeries), and an
excision of anterior 10mm of the muscle 5 with myochol injection to the remaining posterior muscle. Two months following the
surgery the eye was again 50 PD exotropic. An MRI showed reattachment of lateral rectus stump to the sclera near the level of
the equator. Finally, we performed a posterior excision of LR remnants via a lateral orbitotomy.
Lateral Orbitotomy technique: A skin incision is made in the lateral canthal area, soft tissue is spread out down to the periosteum of the
lateral orbital wall. A vertical incision is made in the lateral orbital rim periosteum, with peeling of this layer. The bone is cut using a
saw superior to the level of the zygomatic arch and take off at the level of Whitnall's tubercle. The lateral wall is removed and kept
in moist gauze. The periorbita is incised at the level of the lateral rectus muscle, the LR is lifted on a squint hook.
At the end of surgery the periorbita is sutured, the bone is positioned back in place and sutured to the wall. The periosteal lining is
re-sutured.
Fig.1: patient N1
(Pre-op)
Conclusion: Lateral orbitotomy for posterior lengthening/extirpation of lateral rectus in
resistant exotropia, when a standard anterior approach for surgery is not feasible after
repeated surgery on LR, is a safe and effective surgical procedure for restoring ocular
alignment in persistent exodeviation.
References:
1-Arai H et al. Lateral approach to intraorbital lesions: anatomic and surgical considerations. Neurosurgery 1996;39(6):1157-1163.
2-Velez F, Thacker N, Britt M, Alcorn D, Foster R, Rosenbaum A. Rectus muscle orbital wall fixation: a reversible profound weakening
procedure.
J AAPOS. 2004 Oct;8(5):473-80
3-Morad Y, Kowal L, Scott A. Lateral rectus muscle disinsertion and reattachment to the lateral orbital wall. BJO 2005;89:983-985.
4-Salazar-Leon JA, Ramirez-Ortiz MA, Salas-Vargas M. The surgical correction of paralytic strabismus using fascia lata. J Pediatr
Ophthalmol Strabismus 1998;35:27-32.
5-Sato M, Maeda M, Ohmura T, et al. Myectomy of lateral rectus muscle for third nerve palsy. Jpn J Ophthalmol 2000;44:555-558.