Dennis T. Lanigan

Aseptic necrosis following maxillary osteotomies: report of 36 cases

The sequelae of insufficient vascularity following maxillary orthognathic surgery can vary from loss of tooth vitality, to periodontal defects, to tooth loss, to loss of major maxillary dentoalveolar segments. The results of a questionnaire mailed to oral and maxillofacial surgeons found this complication was most likely to occur with Le Fort I osteotomies done in multiple segments in conjunction with superior repositioning and transverse expansion. Significant palatal perforations definitely seem to compromise the already tenuous blood supply to the anterior maxilla. Suggestions are given regarding the prevention and treatment of this complication.

Trigeminocardiac reflexes: maxillary and mandibular variants of the oculocardiac reflex.

Three case reports are presented to illustrate the existence and importance of reflex bradycardic responses that can occur during maxillofacial surgical procedures. All three patients were healthy young adults undergoing operations which did not include any manipulation of orbital structures. After the patients had been anaesthetized for some time and were haemodynamically stable, profound bradycardia or ventricular asystole occurred suddenly in response to manipulations of the bony structures of the maxilla or mandible, or dissection of, or traction on, the attached soft tissue structures. The parasympathetic supply to the face is carried in the trigeminal nerve. Alternative afferent pathways must exist via the maxillary and/or mandibular divisions, in addition to the commonly reported pathway via the ophthalmic division of the trigeminal nerve in the classic oculocardiac reflex. The efferent arc involves the vagus, regardless of which branch of the trigeminal nerve transmits the afferent impulses. All patients undergoing maxillofacial procedures should be monitored carefully for reflex bradycardia and ventricular asystole.RésuméVoici trois cas mettant en lumière l’existence d’une importante bradycardie réflexe pouvant survenir pendant une intervention chirurgicale maxillofaciale. Alors que l’anesthésie durait depuis un bon moment, que leur hémodynamie était stable, et en l’absence de manipulation des structures de l’orbite, nos trois patients, de jeunes adultes, devinrent sévèrement bradycardes ou asystoliques pendant la mobilisation du maxillaire supérieur ou inférieur ou la dissection/traction des tissus s’y rattachant. Le trijumeau assure l’innervation parasympathique de la face. On connaît bien le réflexe oculocardiaque qui passe par la branche ophtalmique du trijumeau. Les branches maxillaires et/ou mandibulaires du nerf peuvent done aussi transporter des afférences initiant un reflexe similaire avec efférence vagale. Soyons dorénavant aux aguets d’une bradycardie réflexe ou d’une asystolie ventriculaire lors des chirurgies maxillofaciales.

Major Vascular 'Complications of Orthognathic Surgery: Hemorrhage Associated With Le Fort I Osteotomies

Major intraoperative or postoperative bleeding associated with Le Fort I osteotomies can be venous and/or arterial in nature. Arterial hemorrhage generally involves the maxillary artery and its terminal branches. Arterial hemorrhage tends to be more persistent and can be recurrent, which makes it more difficult to manage. Postoperative bleeding following Le Fort I osteotomies generally presents as epistaxis and usually occurs initially within the first 2 weeks following surgery. Treatment modalities that have been used to successfully arrest postoperative hemorrhage include anterior and/or posterior nasal packing; packing of the maxillary antrum; reoperating with clipping or electrocoagulation of bleeding vessels, or the use of topical hemostatic agents in the pterygomaxillary region; external carotid artery ligation; and selective embolization of the maxillary artery and its terminal branches.

Ophthalmic complications associated with orthognathic surgery

Ophthalmic complications are rare following maxillary osteotomies. Potential complications include a decrease in visual acuity, extraocular muscle dysfunction, neuroparalytic keratitis, and nasolacrimal problems involving both an increase or a decrease in tearing. Ophthalmic injuries appear to be primarily mediated through indirect injuries to neurovascular structures occurring from traction, compression, or contrecoup injuries from forces transmitted during the pterygomaxillary dysjunction using an osteotome or from fractures extending to the base of the skull or orbit associated with the pterygomaxillary dysjunction or the maxillary downfracture. A review of the literature of previous ophthalmic complications as well as eight new cases are reported. The possible etiologic basis for these injuries is discussed in detail as well as treatment possibilities when appropriate.

Hemorrhage following mandibular osteotomies: A report of 21 cases

Hemorrhage associated with mandibular osteotomies, especially to the extent that it becomes life threatening, is a rare occurrence and its risk is less than that following maxillary orthognathic surgery. Twenty-one cases of significant bleeding following mandibular sagittal split ramus osteotomies, vertical and oblique ramus osteotomies, and genioplasties are presented. Life-threatening hemorrhage associated with mandibular osteotomies is primarily an intraoperative problem and the incidence of major postoperative and recurrent hemorrhage is not as great as following maxillary osteotomies. Suggestions for the avoidance and treatment of these bleeding complications are discussed.

Alternative approaches to pterygomaxillary separation

Pterygoid plate fractures, resulting from the pterygomaxillary separation in a Le Fort I osteotomy, may be associated with untoward fractures that extend to the base of the skull and orbit and which can lead to rare but significant complications. Five alternative approaches to the pterygomaxillary dysjunction were studied in 50 fresh cadavers. The results of this study show that the use of a curved Obwegeser osteotome to achieve the pterygomaxillary dysjunction should be abandoned, as it leads to an unacceptably high incidence of high-level pterygoid plate fractures at, or near, the base of the skull. The best results were obtained with a Stryker micro-oscillating saw.

Difficult tracheal extubation

We describe a case of nasotracheal tube fixation with a screw. A second case is described in which a broken drill bit was found to impinge on the wall but not penetrate into the lumen of a nasotracheal tube. Possible sequelae of this complication include airway leak, aspiration, tube obstruction, and trauma from attempts at forceful extubation. We recommend the routine intraoperative testing for tracheal tube movement and routine fibreoptic bronchoscopy through the tube when blind surgical procedures occur in the vicinity of a tracheal tube.RésuméOn communique un cas de fixation du tube nasotrachéal par une vis. Un deuxième cas est décrit ou la meche brisée d’une perceuse s’est appuyée sur la paroi du tube nasotrachéal sans le percer. Les complications possibles sont les suivantes: perte d’air du tube nasotrachial, aspiration bronchique, obstruction du tube nasotrachéal et une lésion secondaire a une extubation traumatique. Nous recommendons que la mobilité du tube trachéal soit examinée de routine au cours de l’opération et qu’une bronchoscopie flexible soit faite de routine par le tube trachéal quand une procedure chirurgicale n’est pas faite sous vision directe dans la proximité d’un tube trachéal.

Retrograde Hemorrhage (Hemolacria) From the Lacrimal Puncta After a Le Fort I Osteotomy: A Report of 2 Cases and a Review of the Literature

c a c t l fi a m t d p a cquired lacrimal obstruction caused by trauma, inflamation, and ablative or corrective surgeries can potenially occur in various anatomical regions of the nasolacimal system. The incidence of a nasolacrimal pparatus injury in the nontrauma setting, however, is xceedingly low. Occasionally, damage to the distal acrimal duct apparatus has been associated with epihora, the continuous accumulation of tears in the lacimal lake, due to an impeded outflow. Although the istal portion of the lacrimal apparatus is normally proected within a bony framework, it has the potential to e obstructed secondarily after maxillectomies, maxilary and/or nasal osteotomies, midfacial fractures, and ntrostomies. The nasolacrimal obstruction that folows these events normally occurs early during the postperative phase and is typically transient and self-limitng. This obstruction is generally secondary to edema, hich creates a temporary functional blockage to the assage of tears. Only rarely does surgical disruption of he nasolacrimal system lead to a permanent obstrucion, resulting in persistent epiphora and/or recurrent acryocystitis. Even fewer reports have discussed hemolacria, hemrrhage from the lacrimal puncta, because of retrograde lood flow from the nasolacrimal system. Although