Presented at the Meeting of the Southern Section of the American Laryngological, Rhinological and Otological Society, Inc., New Orleans, Louisiana, January 15, 1999.
Objective To describe a lateral preauricular temporal approach for resection of juvenile nasopharyngeal angiofibroma (JNA).
Study Design A retrospective review of five patients with JNA tumors that were resected by a lateral preauricular temporal approach.
Methods The medical records of five patients who underwent resection of JNA tumors via a lateral preauricular temporal approach were reviewed, and the following data collected: tumor extent, blood loss, hospital stay, and surgical complications.
Results Five patients with JNA tumors had resection by a lateral preauricular temporal approach. These tumors ranged from relatively limited disease to more e-tensive intracranial, e-tradural tumors. Using the staging system advocated by Andrews et al., 1 these tumors included stages II, IIIa, and IIIb. Four patients (stages II, IIIa, IIIa, and IIIb) who underwent primary surgical excision had minimal blood losses and were discharged on the first or third postoperative day with minimal transient complications (mild trismus, frontal branch paresis, serous effusion, and cheek hypesthesia). The remaining patient (stage IIIb) did well after surgery, despite having undergone preoperative radiation therapy and sustaining a significant intraoperative blood loss. There have been no permanent complications or tumor recurrences.
Conclusions A lateral preauricular temporal approach to the nasopharynx and infratemporal fossa provides effective exposure for resection of extradural JNA tumors. The advantages of this approach include a straightforward route to the site of origin, the absence of facial and palatal incisions, and avoidance of a permanent ipsilateral conductive hearing loss.
Juvenile nasopharyngeal angiofibromas (JNA tumors) are highly vascular neoplasms that most commonly arise in the head and neck region of adolescent male patients. These benign tumors originate along the posterolateral nasal cavity near the petroclival fissure and from this region of initial growth may spread extensively following the natural soft tissue planes. 1,2 When significantly advanced, these angiofibromas can result in bone destruction and eventual intracranial extension. Although radiation therapy and chemotherapy have met with some success in the treatment of JNA tumors, the current consensus for optimal treatment of these benign vascular neoplasms remains surgical resection with the former modalities of therapy being reserved for unresectable disease. The benign nature of these tumors, combined with the relatively low overall recurrence rate, supports surgical removal provided that resection does not result in significant loss of form or function.
The variety of surgical approaches to JNA resections that have been described in the literature provides an indication of the complexity of tumor resection in this region of difficult exposure and important anatomical structures. However different in their approach, common to each of these methods is the straightforward goal of maximizing exposure and vascular control with minimal associated morbidity. Specific considerations that are essential to surgical design include an accurate determination of each of the following: the extent of tumor spread, the vascular supply to the tumor bed, and the ability to gain secure vascular control. Advancements in skull base surgery have helped achieve the goals of surgical resection by improving surgical access and vascular control, thereby lowering overall morbidity. Moreover, extensive JNA tumors of the past that were treated with primary radiotherapy would, perhaps, be initially approached surgically today.
Appropriate surgical planning depends on a thorough understanding of the routes of growth of these neoplasms. JNA tumors are known to initiate their growth of fibrous tissue and epithelial vascular spaces in the area of fusion of the superior portion of the pterygoid process of the sphenoid bone, the horizontal portion of the posterior vomer, and the sphenoidal process of the palatine bone. 2 In this region of the pterygopalatine fossa lies the sphenopalatine, artery which is the primary initial blood supply to angiofibromas. As these tumors expand, vascular supply is increased from feeding arteries derived from the internal carotid artery system.
Initially, the tumor growth extends along a submucosal plane to involve the nasopharynx, nasal cavity, and sphenoid sinus. Growth then can occur from the sphenopalatine foramen laterally into the pterygomaxillary fissure and eventually into the infratemporal fossa. From this location, the tumor can invade the orbit via the inferior orbital fissure. Intracranial extension of the tumor to involve the anterior and middle cranial fossae is permitted by destruction of the base of the pterygoid process. The mechanism of bone destruction of these aggressive vasoformative tumors is known to result from a pushing pattern of growth rather than one of infiltration. For this reason, intracranial extension is usually extradural. 1
Several surgical approaches have been used to remove JNA tumors. For disease confined to the nasopharynx, nasal cavities, and ethmoid and sphenoid cavities, endonasal endoscopic, transfacial, midfacial degloving, and transpalatal approaches have been used successfully. 3–6 For lateral extension into the maxillary sinus cavity, transantral exposure has been used, in addition to the aforementioned approaches. 3 Tumors that extend into the pterygomaxillary space, infratemporal fossa, and orbit require wider skull base exposure for safe removal. A variety of approaches have been used to access these more extensive extradural JNA tumors, including 1) facial translocation; 2) transpalatal, transfacial, or midfacial degloving approaches combined with a transzygomatic exposure; 3) a lateral preauricular approach, which is combined with a frontotemporal craniotomy for intracranial disease; 4) postauricular infratemporal fossa approaches that sacrifice the middle ear space, and 5) infratemporal fossa approaches that preserve the middle ear space. 7–16
The combined transzygomatic and transpalatal excision of JNA tumors can be used to remove large tumors with limited intracranial, extradural extension. 13 In this approach, the tumor is delivered through an extended palatobuccal incision. The transzygomatic exposure includes a bicoronal incision, which is required to safely mobilize the superior extent of the tumor. While this approach provides excellent exposure for many large JNA tumors, it is limited to those with a modest amount of intracranial involvement, because of the limited exposure of the middle cranial fossa. The transfacial and midfacial degloving approaches can also be combined with the transzygomatic approach for good exposure of most tumors. However, similar to the combined transzygomatic and transpalatal approaches, exposure of the middle cranial fossa is limited.
The facial translocation procedure as described by Janecka et al. 14 affords excellent exposure of large tumors through modified Weber-Ferguson and coronal incisions. Exposure includes division and reanastomosis of the temporal branch of the facial nerve and sacrifice of the infraorbital nerve. Then a frontotemporal craniotomy is performed. Although this approach offers excellent exposure of large JNA tumors, it is associated with facial incisions, some degree of forehead weakness, and cheek and upper lip numbness.
The Fisch infratemporal fossa type C approach offers excellent skull base exposure for extra-dural tumors. 1,8 With this procedure, a postauricular approach is used to perform a mastoidectomy and subtotal petrosectomy. The mandibular branch of the trigeminal nerve is sectioned, and after tumor removal the middle ear structures are removed, middle ear obliterated, and the eustachian tube closed. This approach allows the patient to avoid facial incisions and a craniotomy; but it results in a permanent ipsilateral conductive hearing loss and chin numbness.
The combined frontotemporal and lateral infratemporal fossa approach to the skull base as described by Mickey et al. 9 provides excellent exposure of the anterior portion of the cavernous sinus and orbital apex and allows for the safe removal of both extradural and intradural intracranial tumors. In this technique, the infratemporal fossa is approached laterally through a preauricular incision and the zygomatic arch and lateral orbital rim are temporarily removed. Similar in this type of exposure are the lateral preauricular approaches reported by Gates 16 and by Zhang et al. 15 in their type D approaches. All three authors report excellent anterior exposure with the advantage of preserving the integrity of the middle ear space.
Although the approach described in this report developed as a modification of the Fisch infratemporal fossa type C procedure and is similar to the Fisch type D procedure, the technique used in our series differs from these and other preauricular approaches in the extent of dissection necessary for exposure. This procedure is described in detail, and five illustrative cases are presented to demonstrate how this lateral preauricular approach can be used for all extradural stages of JNA.
Five patients have undergone JNA resection by a lateral preauricular infratemporal fossa approach by the senior author (j.d.b.). Each case is discussed, and the specific surgical procedure described.
An 11-year-old boy presented with a 4-month history of nasal obstruction and epistaxis. Physical examination was limited by turbinate hypertrophy, which did not permit visualization of the nasopharynx. A contrasted computed tomography (CT) scan was performed, which demonstrated a mass in the area of the lateral nasopharynx with erosion of the pterygoid plates and a radiographic appearance consistent with a stage II angiofibroma. The patient underwent preoperative embolization of the right-side external carotid artery feeder vessels. The following day, the patient was taken to the operating room, where the tumor was removed through a right-side (preauricular), anterolateral subcranial approach. The surgical findings included a tumor arising from the right-side petroclival fissure with erosion of the pterygoid plates and extension into the nasopharynx without intracranial involvement. The total blood loss was 100 mL. Postoperatively, the patient demonstrated only mild, transient trismus. His unilateral nasal packing was removed on the second postoperative day, and he was discharged to home the following day. Follow-up CT scans at 3 and 14 months revealed complete removal tumor.
A 16-year-old boy presented with an 18-month history of nasal obstruction and intermittent right epistaxis. Physical examination revealed a right-side serous effusion, hyponasal speech, and mucoid rhinorrhea with a vascular mass in his right posterior nasal cavity. CT and magnetic resonance imaging (MRI) scans were obtained, which revealed a large enhancing mass filling the nasopharynx with extension into the maxillary, posterior ethmoid, and sphenoid sinuses and further intracranial/extradural involvement in the area of the foramen rotundum consistent with a stage IIIb JNA tumor. The circulation from both external carotid arteries was heavily embolized, and tumor extirpation was performed the following day.
Intraoperatively, a large angiofibroma was found to be arising from the right-side petroclival fissure with extension into the infratemporal fossa. Bony erosion was seen around the foramen rotundum with superior displacement of the maxillary division of the trigeminal nerve with intracranial, extradural extension into the middle cranial fossa. The tumor was removed through an anterolateral preauricular subcranial approach, as described later. This approach allowed dissection of the tumor from the second division of the trigeminal nerve (V2) and the adjacent dura. The patient remained hemodynamically stable during the procedure, sustaining a total blood loss of 200 mL. After surgery, he demonstrated mild, transient paresis of the frontal branch of the facial nerve, hypesthesia of V2, and mild trismus. On postoperative day 2 his nasal pack was removed without bleeding, and the patient was discharged to home on postoperative day 3. Six months after surgery, the patient's serous effusion and motor (forehead branch of facial nerve) and sensory (V2) deficits had completely resolved. Two years after surgery, the patient remained free of disease.
A 9-year-old boy presented with a 9-month history of nasal congestion and a 3-week history of left-side frontal headaches and left-side proptosis. 10 An infused CT scan was performed, which revealed a large mass with radiographic imaging consistent with JNA. The mass was invading the left-side infratemporal fossa with extension into the sphenoid sinus and destruction of the sella turcica with upward displacement of the cavernous portion of the left internal carotid artery (stage IIIb). Because of the patient's age and the extensive nature of his disease, the child underwent 3454 cGy of radiation therapy via linear accelerator. This measure resulted in a significant decrease in the tumor size and a resolution of his symptoms. The mass remained stable over the next 3.5 years, as was documented by serial MRI scans. After this time, however, the patient began complaining of increasing nasal obstruction. An MRI scan revealed the tumor to have increased by approximately 20% with continued extension into the right-side nasal cavity and sphenoid sinus. There was continued extension of disease into the region of the cavernous sinus and base of the middle cranial fossa with elevation of the temporal lobe (Fig. 1).
At 13 years of age, the patient was referred to the senior author for resection and subsequently prepared for definitive extirpation by preoperative embolization. However, multiple large bilateral cavernous carotid artery feeders (greater on the ipsilateral side) could not be embolized. Although the potential consequence of significant intraoperative blood loss was appreciated, preoperative permanent balloon occlusion of the larger ipsilateral internal carotid artery was not performed, because of the young age of the patient. The following day, the tumor was removed via the lateral preauricular temporal fossa and midfacial degloving approaches. The tumor was found to occupy the entire nasopharynx with bone erosion over the left-side orbital apex, left cavernous sinus, and adjacent sphenoid bone, with some extension and deformity of the contralateral pterygomaxillary fossa. Further, because of prior irradiation, the tumor was found to be densely adherent to the middle fossa and cavernous sinus dura, as well as the contralateral posterolateral nasal wall and nasopharynx. Although a plane of dissection was ultimately defined, intense bleeding was encountered in the area of the petrous carotid, and the wound had to be packed repeatedly and intermittently, according to the rate of hemorrhage and hemodynamic stability of the patient. Total blood loss during the 12-hour procedure was estimated at 10,000 mL; blood products were replaced throughout the surgery to maintain stable cardiopulmonary function. No intradural extension was present, and ultimately, the tumor was removed, leaving the wide dural interface intact.
The patient's postoperative course was uneventful. He was returned to the operating room on postoperative day 6 for nasal pack removal. No bleeding was encountered, and the patient was discharged to home the following day. The child initially experienced mild trismus, which resolved over the following 2 months. The frontal branch of his facial nerve has remained intact without ever demonstrating weakness. Seven years after surgery, he was an active college student without sequelae from his extensive blood product replacements. His 5-year postoperative CT scan revealed no evidence of recurrence (Fig. 2). The only reminder of his surgery is the mild concavity of the left temporal region. His preauricular scar is unnoticeable, and his hair covers the temporal scalp scar.
A 21-year-old man presented with a 2-year history of right-side nasal obstruction that was unresponsive to medical management. Nasal endoscopy revealed a vascular mass obstructing the right posterior nasal cavity. A CT scan revealed findings consistent with a JNA stage IIIa tumor. The patient underwent preoperative embolization followed by surgical removal the same day. Intraoperatively, the tumor was found to erode the right-side lateral and medial pterygoid plates with extension into the infratemporal fossa and intimate association with V2. The tumor was approached by the lateral subcranial method leaving V2 and the posterior orbital floor intact (Figs. 3–9). The surgical procedure was accomplished with a total blood loss of 250 mL. The patient was observed overnight and discharged the following day, after nasal pack removal. After surgery he experienced moderate trismus and hypesthesia of V2. The trismus quickly resolved, and the patient was tolerating a normal diet by the second postoperative week. Cheek sensation had completely returned to normal by the sixth postoperative week. One year after surgery the patient remained free of disease.
As an 8-year-old boy, the patient initially underwent resection of a stage II JNA tumor via a midfacial degloving procedure, followed by endoscopic removal of a 1.5-cm residual mass within the sphenoid sinus 9 months later. Yearly MRI scans obtained through his local physician revealed no evidence of recurrent disease until 12 years of age, when he presented with a 3-month history of progressive nasal obstruction. CT and MRI studies revealed a recurrent stage IIIA JNA tumor filling the nasopharynx and eroding bone at the skull base around foramen rotundum. Review of prior studies suggested that the recurrence arose from tumor that was not appreciated within the ipsilateral pterygoid plates at the initial anteriorly oriented resection. The patient was subsequently referred for surgical therapy and underwent preoperative embolization of multiple bilateral external carotid feeders. Several ipsilateral petrous and cavernous carotid feeders could not be embolized.
Via a preauricular temporal approach, the tumor was removed in total, with an estimated blood loss of 800 mL. Brisk bleeding was encountered during dissection of the tumor away from the skull base and the adjacent exposed and elevated V2 trunk underneath the temporal horn. Unlike the irradiated tumor in patient 3, the lesion was expeditiously dissected to minimize blood loss from the internal carotid feeders. No replacement blood products were necessary. An ipsilateral nasal tampon pack placed at the conclusion of the procedure was removed on the first postoperative day; the patient was discharged on the second postoperative day. Six months after surgery there was no evidence of recurrent disease; postoperative trismus was mild and transient and infraorbital nerve function was normal, despite displacement by the tumor requiring nerve retraction and elevation during tumor removal.
MATERIALS AND METHODS
The patient is positioned in the supine position and placed under general anesthesia, and oral intubation is established. The head is rotated to the contralateral side, and the temporal region shaved and prepped with Betadine. Hemostasis is aided by the injection of 1% lidocaine with a 1:100,000 concentration of epinephrine along the planned line of incision. A curvilinear preauricular incision beginning in the pretragal area and curving in a C-shaped fashion into the temporal fossa is performed (Fig. 4). Sharp dissection is used to elevate the anterior skin flap to the zygomatic arch. Care is taken to avoid injury to the frontal branch of the facial nerve by elevating it with the surrounding soft tissue and periosteum overlying the zygoma (Fig. 5). A microplate is predrilled in the area of the zygomatic arch and the lateral orbital rim in preparation for replacement of this segment of bone at the conclusion of the procedure. The zygomatic arch is removed at its junction with the lateral orbital rim and glenoid fossa; inferior displacement of the zygoma is unnecessary. The temporomandibular joint is left untouched and the parotid is not dissected. After removal of the zygomatic arch, electrocautery is used to perform a subperiosteal elevation of the temporalis muscle from the lateral orbital wall, squamosa of the temporal bone, and the lateral process of the sphenoid, with the muscle pedicled inferiorly on the coronoid process of the mandible. This results in exposure of the bone over the orbital apex and temporal horn, the lateral bone of the greater wing of the sphenoid bone, and the squamosa portion of the temporal bone (Fig. 10).
The extent of bone removal depends on the extent of tumor with varying portions of the lateral orbital wall, orbital apex, and contiguous bone of the greater wing of the sphenoid bone removed down to the middle fossa dura and periorbita as necessary. For tumors that either directly contact dura or significantly involve V2 on preoperative scanning, a small skull base temporal craniectomy overlying the temporal horn is performed with a high-speed drill to allow the temporal lobe dura to be retracted away from tumor and involved trigeminal nerve branches. By gentle elevation of the middle fossa dura, the bone underlying the temporal horn can be sequentially removed up toward the cavernous sinus and petrous carotid, if necessary. Smaller tumors that do not impact V2 or contact dura do not necessarily require dural exposure during the dissection. The lateral pterygoid muscle is mobilized anteriorly and laterally, allowing for improved exposure. As mentioned, the temporomandibular joint and parotid are left undisturbed in this approach.
After this initial exposure, the superior portion of the medial and lateral pterygoid plates are removed by drilling away the remaining sphenoid bone, with the extent of bone removal, again, dictated by tumor extent. The tumor is identified at or just deep to the pterygoid plates. The maxillary division of the trigeminal nerve is identified in the inferior/lateral orbital wall dissection as bone is sequentially removed for tumor exposure; this approach allows for protection and separation of V2 from tumor under direct visualization. In larger tumors, V2 is frequently dehiscent and displaced superiorly by the JNA. It can be identified lying on the surface of the tumor as it is approached laterally (Fig. 6).
The Fisch infratemporal fossa retractor is placed for improved exposure of the tumor. When necessary, the mandibular division of the trigeminal nerve is identified and preserved. Blunt dissection is used to mobilize and sweep the tumor toward the attachments at the lateral nasopharynx, taking care to avoid injury to any adjacent dura, periorbita, or trigeminal nerve branch. A sharp tenaculum is used to firmly grasp and pull the tumor out through the lateral defect while dissection continues with blunt elevators through the defect (Figs. 7 and 8). To routinely avoid extensive blood loss during this portion of the procedure, adequate preoperative embolization is essential. Intracranial, extradural disease can be removed using this approach. If preoperative imaging studies suggest extensive intradural extension, a pterional craniotomy can be performed through the exposure to allow direct visualization and removal of the tumor.
After tumor removal, bleeding is controlled by temporary gauze packing and bipolar cautery. As a dressing, the ipsilateral nasal cavity is filled with nasal tampon packing preceded by lining the operative cavity lined with thrombin-soaked Gelfoam. Approximately half of the temporalis muscle is left pedicled posteriorly and secured against the lateral orbit to fill the temporal fossa and therefore minimize the postoperative depression in this area. The remaining anterior half of the muscle is reserved for rotation into the infratemporal fossa cavity to provide soft tissue bulk in the cavity and as a barrier between the nasal cavity/nasopharynx and dura. Then the zygomatic arch is secured into its original position with titanium miniplates. The scalp incision is closed. A suction drain is placed.
This procedure alone was employed for tumor extirpation for patients 1, 2, 4, and 5. In the case of patient 3, this lateral preauricular approach was combined with a midfacial degloving approach for tumor exposure. Although unnecessary in this series, the preauricular curvilinear temporal incision allows access for expansion of the exposure to include the anterior middle ear space for carotid dissection and exposure, and/or a pterional craniotomy for extensive intradural exposure of tumor and cavernous carotid access.
The evolution and refinements made in skull base surgery, anesthesia, and endovascular neuroradiology have, undoubtedly, expanded the limits of resectability of complex lesions such as JNA tumors. The number and variety of reported techniques attest to the challenges of surgical therapy in this region. Regardless of the route of tumor access, each approach has sought to maximize exposure while limiting morbidity. With these same goals, a lateral preauricular approach was used in this series to expose the anatomical region of tumor origin at the beginning of the dissection and allow direct exposure of the cranial base involved with tumor extension. The potential hazard of leaving behind a nidus of tumor within air cells in and around the pterygoid plates (as seen in patient 5) is minimized by the lateral approach, which allows direct exposure of this area.
The fibrous nature of an embolized JNA allows this tumor to be literally pulled laterally from the nasopharynx via the surgical entry zone, once critical attachments have been severed by drilling, and blunt or sharp dissection (e.g., pterygoid plates, dural adhesions, envelopment of V2, nasopharyngeal mucosa, and pterygoid musculature). Limiting bone removal and exposure to that required for tumor exposure allows flexibility in this approach and its applicability to a wide variation in tumor extent. The preauricular placement of the incision inclusive of the temporal fossa allows potential expansion of exposure via a pterional craniotomy for extensive intradural disease.
The minimal morbidity encountered through this preauricular approach is attributable in part to confining the major surgical approach to a lateral one. In a pure lateral approach, there are no palatal, sublabial, or transfacial incisions; an oral diet is hampered only by mild transient trismus. The nasal packing is only ipsilateral. The middle ear is unharmed, and the eustachian tube is dissected from the tumor with the other muscular and mucosal attachments. For this approach to be used, excellent preoperative embolization of all external carotid feeders is essential. With the exception of the preoperatively irradiated patient 3 with a stage IIIb tumor, no patients required blood replacement.
Although not exclusively employing a lateral approach, the therapy of patient 3 was included in this small series to illustrate the benefit of complementing the lateral approach with an anterior midfacial degloving procedure in very extensive intracranial, extradural lesions involving bilateral nasal walls. Although understandable at the time, it is unfortunate that patient 3 received irradiation, because this led to intense fibrosis at an extensive dural/tumor interface. In this setting of wide dural involvement and multiple bilateral petrous/cavernous carotid feeders remaining after embolization, extensive blood loss was anticipated and experienced. Hemorrhage was significant; nevertheless, this approach allowed careful dissection in a fibrotic surgical field. Separation of tumor from dura was accomplished without a cerebrospinal fluid leak or intracranial complications. Although this lateral approach was beneficial to patient safety, blood loss and surgical time would have been less in a nonirradiated field. Efforts at developing the use of percutaneous, direct puncture therapeutic embolization of vascular neoplasms can significantly complement the care of patients with large JNA tumor with persistent internal carotid feeders following traditional endovascular procedures. 17
As described, this reports summarizes the successful application of a lateral preauricular infratemporal fossa approach to the nasopharynx and skull base to remove JNA tumors ranging in size from small, isolated disease to extensive intracranial, extradural tumors. Unlike prior reports of preauricular and lateral techniques, this series reports a technique involving minimal bone removal that is dictated by tumor extent and involves only the removal of bone away from tumor and dura that is necessary for safe extirpation. The temporomandibular joint, parotid, zygoma, facial nerve, and trigeminal nerve branches are left undisturbed; only the zygomatic arch is temporarily removed. In each case, the approach was well tolerated with minimal morbidity and excellent exposure at the affected skull base. In the four nonirradiated patients in this series, the procedure was combined with preoperative embolization, resulting in minimal blood losses and short hospital stays. Cosmetic deformities are limited to well-hidden scalp and preauricular scars, since all facial incisions are avoided. The temporal fossa depression is minimal and generally covered by hair. The use of this lateral preauricular approach allows flexibility in the degree of bone removal and dural exposure to achieve visualization of the nasopharynx and infratemporal fossa for the safe and complete removal of these tumors. Limiting exposure to this lateral technique minimizes the morbidity encountered with transoral, transmaxillary, or transnasal procedures. When used in conjunction with effective endovascular embolization of the tumor, excision of angiofibromas is straightforward and affords visualization of the tumor base at the beginning of the dissection. This technique should be considered as a preferential (although not exclusive) approach in the resection of all angiofibromas, without limiting its application to only large tumors.