Role of Le Fort type I osteotomy approach in juvenile nasopharyngeal angiofibroma

Abstract

Le Fort type I osteotomy is a fracture that extends from the pyriform aperture to each of the pterygoid plates, resulting in the detachment of the upper jaw from the cranial base. A retrospective study was conducted on 12 patients with juvenile nasopharyngeal angiofibroma (JNA) who underwent the Le Fort type I approach. Preoperatively, all cases were investigated with computed tomographic scans with contrast and angiography with embolisation. This paper highlights the surgical technique, results and treatment morbidity. The average age of the patients was 21 years, average duration of surgery was 3.2 h and average blood loss was 550 ml. All cases had significant symptomatic improvement postoperatively. At 1 year follow up, the authors encountered dental malocclusion in one case and no recurrence of JNA. The Le Fort I osteotomy approach is an excellent approach for the excision of JNA because it allows good surgical exposure, better haemostasis, is cosmetically more acceptable and has a very low morbidity.

Juvenile nasopharyngeal angiofibromas (JNAs) are slow growing yet aggressive neoplasms that are highly vascular, composed of primitive types of vessels and poorly encapsulated, facilitating local invasion. JNA is a rare, benign neoplasm usually affecting adolescent males . It accounts for 0.5% of all head and neck tumours . There is evidence that JNA originates in the region above the sphenopalatine foramen at the junction between the sphenoid process of the palatine bone and the pterygoid process of the sphenoid bone . It grows on a submucosal plane extending to the nasopharynx, nasal cavity and sphenoid sinus and has the potential to reach the infratemporal fossa and orbit via the sphenopalatine foramen and pterygomaxillary fossa. Even rarer is extension of the neoplasm to the cranial cavity .

Various surgical approaches for the excision of this neoplasm have been described. They include lateral rhinotomy, transpalatal, midfacial degloving techniques with medial maxillectomy, Le Fort type I osteotomy, facial translocation and craniofacial resection . Transnasal, transantral approaches such as lateral rhinotomy have been designed to remove a well-circumscribed angiofibroma. Extensive angiofibromas can be removed by other approaches such as midfacial degloving, facial translocation and craniofacial resection.

In 1901, Le Fort described the classic lines of fractures. Le Fort type I osteotomy is a fracture that extends from the pyriform aperture to each of the pterygoid plates, resulting in the detachment of the upper jaw from the cranial base . The main advantages of this approach are the lack of visible scars, clear visibility of resection margins and wide surgical exposure . This article highlights the role of Le Fort type I osteotomy in JNA.

Materials and methods

A retrospective study was conducted at the authors’ tertiary care centre on 12 patients with JNA with no previous history of treatment from 2006 to 2009. The presenting symptoms of the cases were noted and compared pre- and postoperatively. Preoperatively all cases were investigated with a computed tomographic (CT) scan with contrast and were staged according to Radkowski’s staging system as Stage IIa (tumour involving the pterygopalatine fossa). Digital subtraction angiography with embolisation was also performed in all the cases 24 h prior to surgery.

All surgery was performed under general anaesthesia through the submental route of endotracheal intubation. Patients were placed in the supine position with varying degrees of tilt for access. The nasal cavity was decongested and infiltration was given using 2% xylocaine with 1:200,000 adrenaline over the sublabial mucosa and nasal mucosa.

A horizontal incision was made through the gingivobuccal sulcus between the second maxillary premolars. A mucoperiosteal flap was elevated to expose the piriform aperture, nasal spine, floor of the nasal cavity and anterior wall of maxillary sinus. Le Fort I osteotomy was carried out using a microdrill bilaterally extending from the piriform aperture to the posterior maxilla ( Fig. 1 ). A curved chisel was used to complete the pterygomaxillary dysjunction. The nasal septum and vomer were detached from the maxillary crest with a straight chisel. The maxilla was downfractured with the help of two Rowers clamps exposing the maxillary sinus and nasopharynx. A modified Dingman’s gag was inserted to keep the mucosa and maxillary segment retracted, which opened a clear view of the surgical site ( Fig. 2 ).

Fig. 1
The Le Fort type I osteotomy cuts, which extend from the pyriform aperture to each of the pterygoid plates, resulting in the detachment of the upper jaw from the cranial base.

Fig. 2
The wide surgical exposure provided by the Le Fort type I approach and a well-circumscribed JNA.

To gain further access posteriorly, the authors excised the posterior ends of the inferior turbinate and septum. This added exposure allowed them to employ a nasal endoscope and an operating microscope. Once the tumour was removed the maxilla was replaced and plated. The predrilled holes helped achieve good alignment.

The nasal cavity was packed with cotton wool soaked in bismuth iodoform and paraffin pack, which was removed the following morning. The mucosa was closed with a continuous absorbable suture. The patients were allowed fluids after 24 h and subsequently progressed to a soft diet. All patients were operated on by the same surgical team. The time taken to perform the surgery after intubation was recorded. Blood loss was also noted by observing the volume of blood collected in the suction apparatus during surgery. Patients were followed up for 1 year and on review a nasal endoscopic examination and repeat CT scan was done to check for recurrence ( Fig. 3 ).

Fig. 3
CT scan axial cut with contrast depicting the classical contrast enhancing vascular JNA seen in the posterior part of the nasal cavity, nasopharynx and extending to the pterygopalatine fossa.

Results

The 12 patients in the study were young adolescent males aged 15–25 years (mean 21 years). Fifty percent had a tumour on the left side and 50% on the right side. The average duration of the surgical procedure was 3.2 h and the average blood loss during surgery was 550 ml. The size of tumours ranged from 4 to 5.8 cm. All cases were unilateral; arising from the sphenopalatine foramen, extending laterally into the pterygopalatine fossa and anteriorly into the nasal cavity. All cases presented as a well defined lobulated tumour covered with nasopharyngeal mucosa. On histopathological examination, the tumour consisted of proliferating irregular vascular channels within a fibrous stroma. The tumour blood vessels lacked smooth muscle and elastic fibres .The stromal compartment was composed of spindle or stellate shaped plump cells with varying amounts of collagen. Intraoperatively, the entire tumour was removed in toto and no residual tumour was left behind. All cases had significant symptomatic improvement on postoperative follow up.

A visual analogue scale was used to assess the symptoms pre- and postoperatively. Each symptom was defined and graded at the 1 year follow up. Nasal obstruction was defined as the inability to breathe through one or both nasal cavities. Epistaxis was defined as a painless, profuse, spontaneous, unprovoked nasal bleed occurring more than twice a week. Facial deformity was described as an obvious change in facial appearance visible as a swelling. Hyposmia was defined as reduction in the sense of smell and was evaluated using coffee beans. Hearing loss was assessed by tuning fork tests, which included Rinne, Weber, and absolute bone conduction tests. Headache was defined as pain over the face and head mainly localized to the side of lesion for the same duration as the lesion or more. At the 1 year follow up the cases were reassessed and the symptoms were graded as: resolved if there was complete recovery; improved if the patient had intermittent symptoms; same if there was no improvement; and worse if the symptoms had worsened. Table 1 compares the pre- and postoperative (1 year follow up) symptoms of JNA.

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Jan 27, 2018 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Role of Le Fort type I osteotomy approach in juvenile nasopharyngeal angiofibroma

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