NEW APPROACH TO THE NASOPHARYNX: THE MAXILLARY SWING APPROACH William 1. Wei, FRCSE, DLO, Kam H. Lam, MS, FRCSE, FRACS, and Jonathan S. T. Sham, DMRT, FRCR

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A new approach to expose the nasopharynx and the paranasopharyngeal space is described. The maxilla, severed from its bony connections, is swung laterally to provide exposure of the nasopharynx. Tumors in the nasopharynx and the paranasopharyngeal space can be adequately resected and tubings for afterloading brachylherapy can be positioned accurately during surgery. The blood supply of the maxilla is from the attached cheek flap and masseter muscle. Three illustrative cases are presented. The wounds in all of them healed primarily with minimal morbidity. The only disadvantage is the development of mild trismus, which responded to conservative treatment. HEAD & NECK 1991; 13~200-207

Pathologies in the nasopharynx and its adjacent area, and the paranasopharyngeal space, impose a difficult problem in management. This region is not easy to examine without the use of the fiberoptic endoscope' and it is even more difficult to approach surgically. The nasopharynx, because of its position, is

difficult t o approach and to obtain adequate exposure for surgical procedures. This problem is not a new one and was summarized in 1950 by Wilson.2 Since then, a number of surgical approaches were designed to provide adequate access t o the nasopharynx. In most of these procedures, the primary objective was the removal of tumors in the maxillo-ethmoidal region, but they had also been used for extirpation of benign and malignant tumors of the na~opharynx.~ The wide diversity of operations demonstrate that no particular procedure is superior to others. More importantly, in most of the described approaches, the nasopharynx and the paranasopharyngeal space are not adequately exposed to allow an oncological procedure to be carried out. We have developed a new approach to the nasopharynx with adequate exposure for radical resection of a tumor in the region. SURGICAL TECHNIQUE

From the Department of Surgery (Drs. Wei and Lam) University of Hong Kong, Queen Mary Hospital, Hong Kong. and the Department of Radiotherapy and Oncology (Dr. Sham), Queen Mary Hospital, Hong Kong. Acknowledgments. We are grateful to Drs. Homer W.K. Tso. W C Chung, George C K. Lau and Connie Chiu of the Department of Prosthetic Dentistry, University of Hong Kong, for providing prosthetic dental support. and Mr. Anthony C.S. Yiu and Mr P.A. Darton of the Medical Illustration Unit, University of Hong Kong. for the illustrations. Address reprint requests to Dr. Wei at the Department of Surgery, University of Hong Kong. Queen Mary Hospital, Hong Kong. CCC 0148- 6403191/030200- 08 $04.00 0 1991 John Wiley & Sons, Inc

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The operation is performed under general anesthesia with the patient in a supine position and an oral endotracheal tube inserted. The whole face, except the contralateral eye, is exposed. Through a Weber-Ferguson-Longmire incision, the horizontal limb is extended to the zygoma. The vertical limb of the incision extends t o the inner surface of the upper lip and continues on to the hard palate between the two medial incisors. The palatal incision, on reaching the junction be-

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FIGURE 1. Weber- Ferguson-Longmire facial incision continues onto the palate and turns laterally behind the maxillary tuberosity.

FIGURE 4. The maxillary tuberosity is separated from the pterygoid plates by a curve osteotome inserted through the mouth.

FIGURE 5. The maxilla is freed from all bony connections and is only attached by soft tissue to the cheek flap. FIGURE 2. The soft tissue over the maxilla is lifted off to expose a narrow strip of bone for osteotomy. Inset: osteotomy site.

FIGURE 3. Oscillating saw is inserted through the osteotomy on the anterior wall of the maxillary antrum to divide the posterior wall.

Maxillary Swing Approach to Nasopharynx

tween the hard and soft palates, turns laterally to run behind the maxillary tuberosity (Fig. 1). The incision on the face goes through the subcutaneous tissue and muscle to reach the periosteum. This is then lifted off the underlying bone to expose a narrow strip of bone, just adequate for osteotomy (Fig. 2). The cheek flap remains attached to the anterior wall of the maxilla during the whole procedure, and the periosteum over the anterior wall is not elevated. Using an oscillating saw, osteotomies are made on the maxilla. The zygoma is first separated from the maxilla and the osteotomy continues medially on the anterior wall of the maxilla, just below the inferior orbital rim, until the nasal process is divided. The medial wall of the maxilla is also divided with the saw inserted anteroposteriorly. The oscillating saw is then inserted through the maxillary antrum parallel to and below the floor of the orbit to divide the posterior maxillary wall (Fig. 3).This osteostomy is not done under direct vision, and the infraorbital

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nerve and vessels are usually divided during the procedure. The floor of the orbit is, however, always kept intact. The mucoperiosteum over the hard palate is lifted off in the midline and the hard palate is also divided with the oscillating saw. The final osteotomy is to separate the maxillary tuberosity from the pterygoid plates by using a curved osteotome inserted through the mouth (Fig. 4). No attempt is made to preserve the greater palatine vessels. The whole maxilla is now freed from bony connections and can be swung laterally while remaining attached t o the masseter muscle and the cheek flap (Fig. 5 ) . The whole mucosal surface of the nasopharynx, including the roof, posterior wall, and lateral walls with the orifices and cushions of the Eustachian tube, is exposed. A tumor in the fossa of Rosenmuller can be identified (Fig. 61, and en bloc resection of the tumor with the cartilaginous portion of the Eustachian tube and the paranasopharyngeal tissue can be carried out. The internal carotid artery lying posterolaterally to the Eustachian tube can be located by its pulsation. With the maxilla swung laterally, there is adequate space to allow dissection around the internal carotid artery. In certain patients when the resection margin is close, spinal needles can be inserted from behind the ascending rami of the mandible and hollow plastic tubes can be positioned accurately in the nasopharynx (Fig. 7). Postoperatively, a radioactive source can be introduced into these needles and tubes to give further irradiation to the surrounding tissues. After the resection is completed, an inferior turbinectomy on the side of the swing is performed, and the mucosa over the inferior turbinate is dissected out and laid on the bone over the basisphenoid region as a free graft to facilitate healing. The laterally swung maxilla, which is attached to the cheek flap, is then returned. Miniplates and screws are used for fixing t o the zygoma and the opposite maxilla (Fig. 8). A dental plate, which is prepared before the operation, can be fitted onto the upper alveolar ridge. This prevents tilting of the maxilla and facilitates accurate repositioning and fixation of the maxilla bone. A Foley’s catheter with the balloon inflated is inserted to keep the free graft in position, and the nasal cavity is packed. The facial wound is closed in layers, and the palatal incision is closed directly. As the cartilaginous portion of the Eus-

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FIGURE 6. The maxilla attached to the cheek flap is swung laterally to expose the nasopharynx with tumor in the fossa of Rosenmuller.

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FIGURE 7. Needles and plastic tubes for afterloading brachytherapy can be inserted accurately and securely fixed in the nasopharynx after the maxilla is swung laterally.

FIGURE 8. The maxilla is fixed to the zygoma and the opposite maxilla with screws and miniplates.

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FIGURE 9. Case 7. All bony connections of the maxilla are divided.

FIGURE 10. Case 7. The maxilla attached to the cheek flap is swung laterally.

tachian tube is removed, a ventilation tube is inserted into the middle ear to prevent the development of serous otitis media. Postoperatively, no special care is required, and oral feeding is usually restarted on the third day. The Foley’s catheter in the nose is removed on the seventh day after operation and the dental plate at 6 weeks when all the wounds have healed.

cnsE REPORTS Case I. A 35-year-old man with a history of nasopharyngeal carcinoma was treated with radical doses of radiation in China. Recurrent tumor was discovered in the nasopharynx 6 months later. A split-palate approach for the insertion of radioactive gold grains was performed; the tu-

mor in the nasopharynx was controlled with this form of brachytherapy . Flexible endoscopic examination and biopsy was carried out monthly. At 10 months after the brachytherapy, a small recurrent tumor 1cm in diameter was discovered in the left fossa of Rosenmuller. There were no cervical nodes or distant metastases. Resection of the nasopharynx tumor was performed using the maxillary swing approach (Figs. 9 and 10). At surgery, a tumor 1 cm in diameter was found in the fossa of Rosenmuller next to the medial crus of the Eustachian tube opening (Fig. 11);this was resected with an adequate margin (Fig. 12). The patient made a smooth recovery, and examination at 12 months after the operation

adequately exposed. The forcep is on the lateral crus of the left Eustachian tube opening. Medial crus of Eustachian tube (arrow) soft plate (arrow heads).

FIGURE 12. Case 7. Resected specimen showing the tumor with margin.

Maxillary Swing Approach to Nasopharynx

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showed normal facial features and function (Figs. 13 and 14). The nasopharyngeal mucosa has healed completely, and there was no recurrence. About 6 months after the operation, the patient noticed a mild trismus, which responded to conservative management. care 2. A 35-year-old man, who had TINIMo nasopharyngeal carcinoma, received 6100 cGy of radiation. Both the primary tumor in the nasopharynx and the cervical lymph node responded to radiotherapy. Follow-up endoscopy and clinical examination showed no pathology in the nasopharynx nor the neck. Computed tomography, however, showed residual tumor in the paranasopharyngeal space (Fig. 151, but there were no distant metastases. Resection of the nasopharynx, the paranasopharyngeal tissue, and the cartilaginous portion of the Eustachian tube was carried out by the maxillary swing approach (Fig. 16). Myringotomy and grommet insertion were performed at the end of the operation. The patient recovered smoothly from the surgery and at 8 months after resection had no evidence of disease. He developed trismus, which responded to conservative measures. All of his teeth remained viable with no evidence of resorption of maxilla (Fig. 17).

sidual tumor at the nasopharynx, at the paranasopharyngeal space, and in the neck glands. The residual tumor in the neck was treated with radical neck dissection, but the facial vessels were preserved. At the same time, the residual tumor in the nasopharynx and paranasopharyngeal space was removed en bloc through the maxilla swing approach. Although a frozen section of the resection margins showed no residual tumor, in view of the extensive nature of the disease, afterloading brachytherapy was planned. Spinal needles were introduced into the paranasopharyngeal space from behind the ascending rami of the mandible, and flexible hollow plastic tubes were placed on the bed of resection in the nasopharynx (Fig. 18). The patient recovered from the operation, and the radioactive source lg2iridium wires were inserted into the needles and tubings on the fourth postoperative day. The whole set of tubings and needles together with the source were removed 5 days later, having delivered a total of 50 Gy at 0.5 cm from the plane of implant. The patient tolerated all of these well, and the wounds healed primarily. He was last seen 6 months after the operation and had no evidence of local disease. DISCUSSION

geal carcinoma that affected the nasopharynx, the paranasopharyngeal space, and the cervical lymph nodes. Radical doses of radiation in the range of 6100 cGy were given to the tumor sites. The tumor responded initially, but an examination at 10 weeks postradiotherapy showed a re-

The nasopharynx as well as the immediate paranasopharyngeal space is a difficult region to approach because of its position. Lesions in this area are actually located in the center of the head. It is anterior to the upper cervical vertebrae and the brain stem, thus a posterior surgical approach is impossible.

FIGURE 13. Case 7. The facial scar is nearly invisible 12 months after surgery.

FIGURE 14. Case 7. The facial musculature functions normally 12 months after surgery.

Care 3. A 60-year-old man had a nasopharyn-

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FIGURE 15. Case 2. Computed tomography showing residual tumor in the paranasopharyngeal space (arrow).

FIGURE 16. Case 2. Nasopharynx and paranasopharyngeal area adequately exposed for resection after the maxilla is swung laterally (forceps lifting up the posterior wall of the nasopharynx).

FIGURE 17. Case 2. The patient 8 months after surgery showing normal teeth with no resorption of maxilla.

Maxillary Swing Approach to Nasopharynx

Superiorly, the nasopharynx is bounded by the sphenoid sinus and the base of skull. Although pathologies in this region can be approached and resected via the trans-skull base approach as described by D e r ~ m ethere , ~ is a significant morbidity due to exposure of the subarachnoid space to pathogens in the nasal cavity. Because the surgeon has to go through the base of skull, other complications, such as the meningitis, diabetes insipidus, and encephalocele, have been r e p ~ r t e d . ~ The nasopharynx can also be approached lab erally through the infratemporal fossa.6 Using this approach, a radical mastoidectomy must be carried out and some important structures divided or removed. These include the zygomatic arch, bony component of the floor of the middle cranial fossa, middle meningeal artery, and mandibular branch of the 5th cranial nerve. The internal carotid artery also has to be exposed from the middle ear to the foramen lacerum and displaced before entering the nasopharynx. Although tumors affecting the Eustachian tube and lateral paranasopharyngeal space can be removed, the exposure is not adequate for an ontological procedure to be carried out. The nasopharynx can be approached inferiorly via the transpalatal route. In patients with a wide nasopharynx, retracting the soft palate with catheters introduced through the nostrils may provide an adequate exposure of the nasopharynx. Successful removal of a chordoma in the region in this manner has been r e p ~ r t e d . ~ This approach, which obviously has its limitations, is of use only in a small number of patients with a wide nasopharynx. The palate can be incised and retracted to expose the nasopharynx. It is incised transversely and the soft palate retracted,8 or an incision is placed along the inner margins of the upper alveolus, and the mucoperiosteum of the hard palate is lifted up as a flap and retracted posteriorly to expose the nas~pharynx.~ The palate can also be split in the midline and retracted laterally to expose the nasopharynx. Small recurrent tumors have been successfully removed with this approach." We have employed this approach for the insertion of radioactive gold grains in the treatment of recurrent nasopharyngeal carcinoma." We have found that in all instances, although visual exposure of the recurrent tumor in the nasopharynx is adequate, the exposure is not sufficient for surgical resection of the recurrent tumor.

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FIGURE 18. Case 3. After the maxilla is swung laterally, resection of nasopharynx and paranasopharyngeal area completed. Spinal needles are inserted through the paranasopharyngeal space behind the ascending rami of the mandible (left). Hollow plastic tubes are placed on the bed of the nasopharynx through the nose for postoperative brachytherapy (right).

The usual anterior approach to the nasopharynx is disadvantageous because the surgeon has to work through a small opening on the face to remove a tumor deep in the wound. The various transnasal and transantral approaches described by Wilson12 did not give an adequate exposure of' the nasopharynx to allow an oncological surgical procedure t o be carried out. The nasopharynx can be exposed adequately by extending a subtotal maxillectomy or maxillotomy, but in this case, the malar bone and the coronoid process of the mandible must be removed.13 The maxillary swing approach to the nasopharynx as reported here overcomes these drawbacks. After the maxilla is swung laterally on the cheek flap, the whole nasopharynx is exposed. The lateral walls as well as the superior and posterior walls of the nasopharynx can be clearly seen. The exposure is adequate to allow scissors and other instruments to be employed in carrying out a truly oncological resection as illustrated in the 3 cases. The cartilaginous portion of the Eustachian tube is fully exposed after the maxilla is swung laterally. It can be included in the resection. When this is being performed, a ventilation tube

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in the middle ear is mandatory to prevent the development of serous otitis media.'* As the internal carotid artery is in close proximity with pathologies located in the upper paranasopharyngeal space, radical resection of a tumor in this region was previously considered to be dangerous. With the maxillary swing approach, the paranasopharyngeal space is adequately exposed to allow precise dissection. The carotid artery can be palpated easily, and tissues around it can be removed adequately with the artery safeguarded. Oncological resection of a tumor in this region is possible as illustrated in the second and third patients. Because the exposure of the nasopharynx with this approach is adequate, part of the skull base can be included in the resection if deemed necessary. When the resection margin of the tumor is considered to be close, then needles and tubings for afterloading brachytherapy can be placed accurately and secured precisely during the surgery. With the identification of the internal carotid artery at operation, the danger of its injury during the insertion of the needles is minimized as illustrated in the last patient. In the first patient, in whom the internal

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maxillary artery was left intact, the viability of the maxilla depends on the masseter muscle insertion over the zygoma and from the cheek flap, which in turn is nourished by the facial and superficial temporal vessels. In the second and third patients, who had resection of paranasopharyngeal space tissue, the internal maxillary artery was divided. The blood supply to the maxilla is then solely from the attached cheek flap. These sources of blood supply are apparently adequate, as the wounds of all 3 patients healed primarily despite previous radiotherapy. The last patient had additional postoperative brachytherapy, but the wound on his face healed very well and was hardly noticeable after 6 months. Trismus developing postoperatively was, to a variable degree, a definite problem in all patients. This was probably due to fibrosis at the pterygoid region after the surgical dissection. Fortunately, in all patients, this responded significantly to passive stretching with no functional disability. In our opinion, the maxillary swing approach to the nasopharynx can be recommended for the management of small recurrent or persistent nasopharyngeal carcinomas after radiotherapy. A curative resection is possible with this approach.

When the tumor has extended to involve the paranasopharyngeal space, radical resection is still possible. If the resection margin is close, tubings should be placed at the time of the operation for afterloading brachytherapy . The maxillary swing approach can .also be recommended for the management of congenital cranio-vertebral bony anomalies in the midline, or hemangioma in the nasopharynx where adequate exposure is necessary, either for correction or vascular control. Recurrent angiofibroma involving the skull base can be adequately exposed with this approach. A previous lateral rhinotomy or transpalatal resection scars can all be incorporated into the incision for the maxillary swing approach. CONCLUSION

The maxillary swing approach t o the nasopharynx offers adequate exposure of the whole nasopharynx and the paranasopharyngeal space. Bony and soft tissue reassembly is not difficult, and the resultant morbidity is minimal. It is recommended for surgical management of pathologies in the nasopharynx and its immediate neighborhood, especially for small recurrent or persistent nasopharyngeal carcinomas after radical radiotherapy.

REFERENCES

1. Wei WI, Lau WF, Lam KH, Hui Y. The role of the fiberoptic bronchoscope in otorhinolaryngological practice. J Laryngol Otol 1987;101:1263- 1270. 2. Wilson CP. The approach to the nasopharynx. Proc R SOC Med 1950;44:353-358. 3. Maran AGD. Surgical approaches to the nasopharynx. Clin Otolaryngol 1983;8:417-429. 4. Derome PJ. The transbasal approach to tumors invading the base of the skull. In: Schmidek HH, Sweet WH, eds. Operative neurosurgical techniques, vol 1. New York, Grune & Stratton, 1982:357-379. 5. Van Buren JM, Ommaya AK, Ketcham AS. Ten years’ experience with radical combined craniofacial resection of malignant tumors of the paranasal sinuses. J Neurosurg 1968;28:341-350. 6. Fisch U.The infratemporal fossa approach for nasopharyngeal tumors. Laryngoscope 1983;93:36-44. 7. Mullan S, Naunton R, Hekmat-Panah J , Vailati G. The use of a n anterior approach to ventrally placed tumors in the foramen magnum and vertebral column. J Neurosurg 1966;24:536- 543. 8. Ruddy LW. A transpalatine operation for congenital atresia of the choanae in the small child or the infant. Arch Otolaryngol 1945;41:432-438.

Maxillary Swing Approach to Nasopharynx

9. Owens H.Observations in treating seven cases of choanal atresia by the transpalatine approach. Lavngoscope _. . . 1951;61:304-319. 10. Fee WE. Jr.. Gilmer PA. Goffinet DR. Sureical manaaement of recurrent nasopdaryngeal carcinoma after radiation failure at the primary site. Laryngoscope 1988;98:1220- 1226. 11. Wei WI, Sham JST, Choy D, Ho CM, Lam KH. Split-palate approach for gold grain implantation in nasopharyngeal carcinoma. Arch Otolaryngol Head Neck Surg 1990;116:578-582. 12. Wilson CP. Observations on the surgery of the nasopharynx. Ann Otol Rhino1 Laryngol 1957;66:5-40. 13. Cocke EW Jr., Robertson JH , Roberston JT, Crook J P Jr. The extended maxillotomy and subtotal maxillectomy for excision of skull base tumors. Arch Otolaryngol Head Neck Surg 1990;116:92-104. 14. Wei WI, Engzell UCG, Lam KH, Lau SK. The efficacy of myringotomy and ventilation tube insertion in middleear effusions in patients with nasopharyngeal carcinoma. Laryngoscope 1987;97:1295- 1298. I

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New approach to the nasopharynx: the maxillary swing approach.

A new approach to expose the nasopharynx and the paranasopharyngeal space is described. The maxilla, severed from its bony connections, is swung later...
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