Abstract
Background
Currently described endoscopic techniques for subtotal resections of the maxilla include endoscopic medial maxillectomy and extended endoscopic medial maxillectomy; however, a complete resection of the maxilla is sometimes warranted. We describe a combined transoral and endoscopic technique for total and subtotal maxillectomy in an attempt to decrease the morbidity of traditional approaches.
Methods
Technical note, Feasibility, Human cadaveric dissection.
Results
Ten total and subtotal maxillectomies were performed in human specimens without the need of facial incisions or transfixion of the nasal septum. The pterygopalatine and infratemporal fossas were accessed and dissected in all cases.
Conclusions
A combined transoral and endoscopic approach is feasible and can be used in selected patients when other minimally endoscopic techniques are not indicated. The benefits of no facial incisions and/or transfixion of the nasal septum, potential improvement in hemostasis, and visual magnification may help to decrease the morbidity of traditional open approaches.
1
Introduction
Extensive maxillectomies, such as total and subtotal maxillectomies, are performed to resect malignant and extensive benign tumors of the maxillary bone and associated soft tissues. Multiple surgical approaches have been developed to resect the maxilla over the past several decades, which include lateral rhinotomy (LR) and Weber-Ferguson extension (WFE). These approaches are still widely used despite leaving facial scars that can be unsightly.
More recently, endoscopic procedures have been proposed to manage malignant tumors of the maxilla, such as the endoscopic medial maxillectomy and extended endoscopic medial maxillectomy . However, these techniques can be insufficient to completely resect a large tumor of the maxilla, especially if the tumor involves the lateral, inferior, or anterior wall of the maxillary sinus.
We present a surgical approach and technical note based on the combination of the endoscopic and transoral techniques, which allows extensive resection of the maxilla, offers the possibility of extending the endoscopic dissection into the infratemporal and pterygopalatine fossas (ITF and PPF, respectively), improves cosmesis, and can potentially improve hemostasis.
2
Material and methods
Five preserved human specimens were used for anatomical dissections in accordance with institutional protocols. Karl Storz endoscopes (Tuttingen, Germany) with 4 mm in diameter; 18 cm in length; and 0°, 30°, 45°, and 70 ° lenses were used for visualization. A high-speed drill (Stryker, Kalamazoo, MI) with a Saber 5100-120 handpiece, microdebrider (Medtronic, Minneapolis, MN), straight guarded burrs, and angled diamond bit burrs were used for the bone work.
2
Material and methods
Five preserved human specimens were used for anatomical dissections in accordance with institutional protocols. Karl Storz endoscopes (Tuttingen, Germany) with 4 mm in diameter; 18 cm in length; and 0°, 30°, 45°, and 70 ° lenses were used for visualization. A high-speed drill (Stryker, Kalamazoo, MI) with a Saber 5100-120 handpiece, microdebrider (Medtronic, Minneapolis, MN), straight guarded burrs, and angled diamond bit burrs were used for the bone work.
3
Anatomy
The maxillary bones are the second largest bones of the face and form the entire upper jaw. They form some of the boundaries of the ITF and PPF, and inferior orbital and pterygomaxillary fissures. Each bone has a body and 4 processes: zygomatic, frontal, alveolar, and palatine. The body contains the maxillary sinus, which has a pyramidal shape and 4 surfaces: anterior, posterior, superior, and medial. The nasal wall forms the base of the pyramid, whereas the apex extends into the zygomatic process of the maxilla. The infraorbital canal will be found on the roof of the sinus. Posterior to the canine region, the medial or lingual wall of the alveolar process will join the lateral wall of the nose, whereas the lateral or buccal wall of the alveolar process will join the facial wall of the maxilla. Therefore, the dental alveoli will form the floor of the maxillary sinus , which is usually below the level of the nasal cavity. The roots of the first and second molars and, occasionally, other teeth are included in the floor of the sinus . The limits of the posterolateral wall are the ITF and PPF. The anterior wall is slightly concave and has the infraorbital foramen, where the infraorbital nerve (ION) exits the maxilla .
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Technical note
The procedure is started by performing a total ethmoidectomy (or inferior/subtotal ethmoidectomy) and a wide maxillary antrostomy with standard sinus or powered instrumentation. This is followed by the resection of the medial wall of the maxillary sinus (including the inferior turbinate) and the inferior aspect of the middle turbinate.
Subsequently, an incision is performed at the level of the ipsilateral gingivobuccal sulcus. The incision is made from the contralateral central incisor to the ipsilateral third molar. Blunt subperiosteal dissection of the soft tissues is performed with a freer dissector along the anterior wall of the maxillary sinus, until locating the ION superiorly and the zygomaticomaxillary fissure (ZMF) laterally ( Fig. 1 A).
Vertically oriented osteotomies along the intermaxillary fissure or segment, ZMF, and ascending process of the maxilla (APM), and transversally along the superior or inferior margin of the infraorbital neurovascular bundle are performed with powered instrumentation to detach the anterior aspect of the maxilla ( Figs. 1B-D and 2 ).
