It is the purpose of this paper to review the various types of osteotomies which are available for the correction of craniofacial anomalies.
Congenital craniofacial anomalies include variety of conditions such as hypertelorism, Crouzon´s disease, Apert´s syndrome and hemi-facial microsomia etc. Post-traumatic craniofacial anomalies have a traumatic origin, which in early life affecting the growth of craniofacial skeleton or causing a deformity as a result of malunited fracture.
In 1924, Greig introduced the term "ocular hypertelorism" to describe the congenital facial deformity with a "great breadth between the eyes". Many attempts have been made to correct the deformities since 1938, but tried to correct only the extra-orbital malformations (epicanthus, eyebrows, root of the nose). A number of major development have made possible the recent success of craniofacial and mid-facial osteotomies.
The first was disclosure of the remarkable propensity of bone grafts, particularly those consisting of cancellous bone, to bridge gaps over defects of the orbital floor, anterior wall of the maxillary sinus and lateral nasal wall. The second development was the demonstration of success, despite contamination by oral bacteria, of bone grafts and osteotomies through an intra-oral approach(Converse, 1950). The antibiotics undoubtedly contributed to the success of the procedures. In 1952, Gillies performed first high maxillary osteotory successfully for the correction of craniostenosis.
In 1959, Converse and Smith performed corrective surgery on 3 cases of hypertelorism, displaced medial canthus inwardly_ with a part of the medial orbital wall and nasal rim of the orbit, the osteotomies extending through or behind the lacrimal grooves.
In 1962, Tessier displaced the medial canthi, together with the medial orbital walls and the inframedial angles, with the lacrimal apparati. Those mentioned procedures were all doomed to fail, because they moved only small portions of orbital rim, so they had little effect in moving the globe. Subsequently he performed first correction of hypertelorism through a narrow cranial route, which are consisting of two stages. First stage was reinforcement of the dura and after an interval of a number of months, in a second stage, the central portion of the frontonasal skeletal framework and anterior cranial fossa was resected. Medial -orbital displacement was then achieved by medial orbital osteotomy or either by subtotal orbital osteotomy.
In 1969, Converse modified the Tessier´s ´technique and performed one-stage technique with preservation of cribriform plate by resecting the lateral mass of the ethmoid. He insist, this technique preserves the cribriform plate, the olfactory nerve and the sense of olfaction although Tessier do not believe it is always possible to preserve olfaction entirely because the olfactory nerve is very sensitive to retraction.
The menace of injury to the optic nerve is ever-present. Unpredictable hemorrhage in the apex of the orbit may cause blindness without direct injury to the optic nerve during osteotomy. Spinal fluid drainage undoubtedly diminish the chance of cerebral edema which was the main cause of immediate post-operative mortality. Amblyopia does not appear to be corrected and many patients requires subsequent extra-ocular muscle surgery. The optimal age at which these operation should be performed has not been defined. The age of the patient and the degree and types of hypertelorism will determine the surgeon´s choice of procedure.
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