Access Osteotomies in Oral and Maxillofacial Surgery
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Transcript of Access Osteotomies in Oral and Maxillofacial Surgery
PRESENTERDR.REHANA SULTANA
POST GRADUATE STUDENT
Access osteotomies in oral and maxillofacial surgery
CONTENTS
INTRODUCTIONHISTORYCONCEPT OF MODULAR OSTEOTOMIESVARIOUS OSTEOTOMIES MAXILLARY OSTEOTOMIESMANDIBULAR OSTEOTOMIESMODIFICATIONSCONCLUSIONREFERENCES
Introduction
The craniofacial skeleton can be regarded as an osteoplastic structure as its excellent blood supply allows the mobilisation and replacement of bone fragments,either pedicled on their soft tissues or as free bone segments
History
Von langenbeck in 1859 performed a horizontal osteotomy at the level of fracture line
Later in 1901, it was described as the lefort 1 position to access the pathology in the nasopharynx
Kocher modified vonlangenbeck’s technique by dividing the maxilla in the midline to approach the pituitary fossa
Concept of modular osteotomies
Various osteotomies to access various areas
Infratemporal fossa :zygomatic arch osteotomy with or without lateral orbital rim or
Inverted L zygomatic bone osteotomy with or without involvement of lateral orbital rim
Lesions involving parapharyngeal, lateral pharyngeal and deep spaces of neck, posterior oral floor, retromaxillary and tonsillar fossa can be accessed by mandibular osteotomies
For increased exposure of the parapharyngeal space, infratemporal fossa and pterygomaxillary region upto the skull base --- a second horizontal osteotomy of the mandibular ramus above the lingula.
Skull base can be approached anteriorly and laterally---bitemporal craniotomy with frontonasalorbital osteotomy
Middle cranial base approaches include Le Fort I maxillary osteotomy, sometimes combined with mandibulotomy and frontonasoorbital osteotomy
Pedicled osteotomy of maxilla/hard palate & zygoma
Maxillary osteotomy
Provides wide exposure of soft palate and nasopharynx
IF INFRAORBITAL NERVE HAS TO BE LIGATED
IF INFRAORBITAL NERVE HAS TO BE SACRIFICED
Nasal osteotomy
Primarily for the resection of any pathology within nasal cavity,ethmoid and sphenoid sinuses
Modification -- maxillary nasal osteotomy
Lefort 1 osteotomy
In 1986, Sailer described the use of the Le Fort I osteotomy as a surgical approach for the removal of pathological conditions within the maxilla.(Sailer and Makek, 1986)
Different approaches for removal of tumours in the midface, pterygomaxillary region, skull base and nasopharynx have been described. Most of these use the Ferguson Weber incision or modifications thereof, giving access to the facial skeleton in order to perform osteotomies or en bloc resections (Shah and Galicich, 1977; Altemir, 1986a; Brusati, 1991; Salins, 1997).
Anatomic boundaries/surgical exposure The LeFort I downfracture creates a funnel-like opening with
a 3:1 ratio of anterior to posterior displacement of the inferior maxilla. The anterior nasal spine travels 3.5-4.5 cm inferiorly compared with the 1-1.5 cm for the posterior nasal spine.
Superior extent: sella turcica, cribiform plate. Inferior extent: C1 (possibly C2) Lateral extent: pterygoid and temporalis muscle Posterior extent: Clivus, posterior wall of sphenoid
sinus, greater wing of sphenoid bone
Accessible areas
View after lefort 1 down fracture
Exposure from posterior ethmoidal cells to craniocervical junction
Advantages
No visible scar
The aesthetic aspect of this approach is not only relevant in younger patients, but is even more important in patients undergoing radiotherapy
Facilitation of the ensuing reconstructive procedures. It allows excellent access to mobilize and fix the buccal fat pad to the medial aspect of the defect following partial maxillary resection in order to cover the nasal aspect of bone grafts in resections involving the whole maxillary sinus floor(Egyedi, 1977; Sailer and Makek, 1986).
Indications : for the tumours situated in or extending into the maxillary sinus, the sphenoid sinus or the nasopharynx
Accessible areas: nasal cavity, maxillary sinuses & nasopharynx
The Le Fort I osteotomy was even described as a single access for exposing the medial compartment of the inferior skull base from the tuberculum sellae to the foramen magnum,in order to perform neurosurgical procedures following pharyngotomy, clivectomy and dural opening (van Loveren et al., 1994).
The LeFort I osteotomy for approaching diseases in the cranial base was first described by Cheever (Moloney and Worthington, 1981) in which a maxillary osteotomy was used for removing a tumour from the nasopharyngeal area.
Limitations: vascular supply to mobilised maxillaRestriction of lateral access due to pterygoid platesThe incidence of other minor intra-operative and
peri-operative complications are considered low (Kramer et al., 2004).
Avascular necrosis of maxilla in 1% of cases (Lanigan, 1997). The possible factors could be rupture of the descending palatine artery (DPA) during surgery (Sasaki et al., 1990), post-operative vascular thrombosis, perforation of the palatal mucosa that impairs blood supply to the maxillary segment (Pereira et al., 2010).
Complications
Rare complications with this procedure includes subcutaneous emphysema (Stringer et al., 1979)
Unilateral abducens nerve palsy (Watts, 1984),
Upper lip hypoesthesia (Ueki et al.,2008) Aseptic necrosis of the maxilla (Lanigan et
al.,1990),Fatal arteriovenous fistula (Laetitia Goffinet
et al.,2010) and Blindness(Cruz and dos Santos, 2006).
Lip split /mandibular split – mandibular swing approach
An incision to divide the lower lip and chin
Division of the mandible anterior to mental foramen
Dissection of tissues in the floor of mouth, submandibular region and neck
Access areas : floor of mouth
Tongue, tonsillar fossa, soft palate, oropharynx including the posterior pharyngeal wall,supraglottic larynx and the pterygomandibular region
MANDIBULAR SWING OSTEOTOMY
Various osteotomies for tumors of parapharyngeal space
The rigid bony walls of the mandible direct tumour growth medially to the parapharyngeal space
Bulge of soft palate is the diagnostic sign
Double mandibular osteotomy with coronoidectomy for tumours in the
parapharyngeal spaceBritish Journal of Oral and Maxillofacial Surgery (2003) 41, 142–146
Vertical ramus osteotomy
Osteotomy in the vertical ramus outside the mandibular foramen for tumours in the
parapharyngeal spaceJournal of Cranio-Maxillo-Facial Surgery 42 (2014) e29- e32
Mandible osteotomies
Inverted L or C osteotomy
Inverted L or C osteotomy
Lateral zygomatic osteotomy
Conclusion
Tumors occurring in the inaccessible regions present a surgical challenge and access osteotomies of the facial skeleton is the answer to access these deeply situated, inaccessible tumors of the head and neck.
Various approaches have been devised for their better exposure and it is our expertise as maxillofacial surgeons to provide surgical access by various approaches.