Facial translocation: a new approach to the cranial base

Advantages and caveats of endoscopic to the infratemporal fossa as isolated and combined techniques

Objective

Identify the benefits and caveats of combining minimal access approaches to the infratemporal fossa (ITF), such as the endoscopic transnasal, endoscopic transorbital, endoscopic transoral, and endoscopic sublabial transmaxillary approaches to address extensive lesions not amenable to a single approach. The study provides anatomical metrics including area of exposure and degree of surgical freedom.

Methods

Five human cadaveric specimens (10 sides) were dissected to expose and methodically analyze the anatomical intricacies of the ITF using the following minimal access approaches: endoscopic transnasal transpterygoid (EETA), endoscopic sublabial transmaxillary, endoscopic transorbital via infraorbital foramen, and endoscopic transoral techniques. Area of exposure at the pterygopalatine fossa and surgical freedom at the ITF were obtained for each approach.

Results

The endoscopic sublabial transmaxillary sinus and the combined approach afford a significantly greater exposure than an isolated EETA. The difference in exposure (mean) between the endoscopic sublabial transmaxillary and EETA was 1.62 ± 0.85 cm2 (p < 0.001), and the difference between the combined approach and EETA was 4.25 ± 0.85 cm2 (p < 0.001).

Conclusions

Combining minimal access endoscopic approaches to the ITF can provide significantly greater exposure than an isolated EETA; thus, providing enhanced access to address lesions with extensive involvement of the ITF, especially those with superolateral and inferolateral extensions. In addition, some approaches may have an adjunctive role to the resection, such as the endoscopic transoral approach offering the potential for early control of the internal maxillary artery and its branches, some of which may be supplying the tumor in the ITF; or the endoscopic transorbital approach yielding a direct line of sight to the superior ITF and middle cranial fossa.

Level of Evidence

NA.

Endoscopic endonasal transpterygoid nasopharyngectomy: Anatomical considerations and technical note

BACKGROUND

The study was designed to identify new landmarks in the parapharyngeal segment of the internal carotid artery (ICA) for nasopharyngectomy and describe a surgical procedure of endoscopic endonasal transpterygoid nasopharyngectomy (EETPN).

METHODS

Four cadaveric specimens were injected with colored silicone and subjected to CT scanning before dissection. The nasopharyngeal skull base was exposed using the endoscopic endonasal transpterygoid approach. The clinical data of four patients with nasopharyngeal malignances who underwent EETPN were reviewed.

RESULTS

The lateral edge of the longus capitis muscle medially; the foramen lacerum, petrous apex spine and the stump of the levator veli palatini muscle superior laterally; and the upper parapharyngeal ICA laterally constitute the ICA-longus capitis muscle-petrous apex spine triangle which was a novel landmark for the upper parapharyngeal segment of the ICA.

CONCLUSION

The ICA-longus capitis muscle-petrous apex spine triangle are important landmarks of the upper parapharyngeal segment of the ICA.

Midface microvascular reconstruction after maxillary complex tumor resection: A retrospective study

The study purpose is to review the surgical approach and evaluate the results in managing patients with advanced midface and maxillary complex tumors. The most common anatomical site of the primary tumor was the maxilla, sometimes with extension to the orbit and anterior fossa, parotid and middle ear or even the lip. Surgical resection included maxillectomy in the majority of cases, combined with orbital exenteration or orbitectomy and anterior fossa resection. Parotidectomy and mastoidectomy/core petrosectomy were also performed. Reconstruction was performed with radial forearm osteocutaneous free flap, latissimus dorsi myocutaneous flap with scapular bone flap, lengthening temporalis myoplasty, rectus abdominis free flap, anterolateral thigh flap, in combination with temporalis and vastus lateralis, as well as pectoralis major myocutaneous flap. A total of 36 midface tumor excisions were performed, followed by the appropriate reconstruction. The average follow-up period was 15 years. To date, 23 patients are disease free, while 6 patients presented disease recurrence and 7 patients died during the 15-year follow-up period. Surgical resection remains the gold standard for midface tumors management. When safely performed, combined with microvascular and dynamic face reconstruction, surgery can offer improvement in quality of life and prolong the overall survival.

Predictors of postoperative performance status after surgical management of infratemporal fossa malignancies

Infratemporal fossa (ITF) tumors are difficult to access surgically due to anatomical constraints. Moreover, aggressive ITF carcinomas and sarcomas necessitate aggressive treatment strategies that, along with tumor-related symptoms, contribute to decreases in patient performance status. To assess factors that predict postoperative performance in patients undergoing surgery for ITF tumors. We reviewed medical records for all patients surgically treated for an ITF malignancy between January 1, 1999, and December 31, 2017, at our institution. We collected patient demographics, preoperative performance, tumor stage, tumor characteristics, treatment modalities, pathological data, and postoperative performance data. The 5-year survival rate was 62.2%. Higher preoperative Karnofsky Performance Status (KPS) score (n = 64; p < 0.001), short length of stay (p = 0.002), prior surgery at site (n = 61; p = 0.0164), and diagnosis of sarcoma (n = 62; p = 0.0398) were predictors of higher postoperative KPS scores. Percutaneous endoscopic gastrostomy (PEG) (n = 9; p = 0.0327), and tracheostomy tube placement (n = 20; p = 0.0436) were predictors of lower postoperative KPS scores, whereas age at presentation (p = 0.72), intracranial tumor spread (p = 0.8197), and perineural invasion (n = 40; p = 0.2195) were not. Male patients and patients with carcinomas showed the greatest decreases in KPS scores between pretreatment and posttreatment. Higher preoperative KPS score and short length of stay were the best predictors of higher postoperative KPS scores. This work provides treatment teams and patients with better information on outcomes for shared decision-making.

Maxillary Swing Approach for Central Skull Base Lesions in Extreme Situations: A Single-Institutional Case Series

OBJECTIVE

Radical resection of complex lesions occupying multiple compartments at the central skull base remains a significant challenge, since surgical outcomes may be compromised by insufficient exposure and inappropriate techniques. However, the efficiency of the maxillary swing approach for these lesions has not been sufficiently evaluated. Careful assessment of lesion characteristics must be performed when selecting the appropriate procedure.

METHODS

Between May 2006 and February 2017, 17 patients underwent resection of extensive lesions in the central skull base using the maxillary swing approach. As shown in the representative cases, data regarding clinical findings and technical considerations were reviewed.

RESULTS

Complete resection was achieved in all patients. The pathological findings were diverse, and the majority were schwannomas (9 cases, 52.94%), followed by meningiomas (World Health Organization II) (3 cases, 17.65%). Complications were managed as described in the case illustrations, and symptoms improved with time. The follow-up duration ranged from 62 to 192 months (median, 114 months), while 2 patients were lost to the follow-up. No mortality was observed. Two patients who experienced malignancy relapse were still under observation due to their asymptomatic status.

CONCLUSIONS

Our preliminary results suggest that the maxillary swing approach can be an alternative option for managing extreme cases, such as large, extensive, hypervascularized masses with fibrous or calcified consistency, or for recurrent lesions in the central skull base. En bloc resection can be successfully obtained, resulting in long-term local control.

Anatomy of the sphenoidal spine and its implications in endoscopic endonasal surgery of the infratemporal fossa

BACKGROUND

The sphenoidal spine protrudes from the roof of the infratemporal fossa (ITF). This study aims to assess the anatomic relationships among the sphenoidal spine and other structures within the ITF from the perspective of an endoscopic endonasal access (EEA), and to explore the implications of these relationships.

METHODS

An EEA to the ITF was completed on six cadaveric specimens (12 sides). The anatomical relationships among the sphenoidal spine and adjacent structures were explored and associated distances from each other were measured using a navigation system.

RESULTS

The foramen spinosum is located anterosuperior to the sphenoidal spine, whereas the chorda tympani courses caudal and medial to the sphenoidal spine and the Eustachian tube and parapharyngeal internal carotid artery (pICA) are at its posterior aspect. Two virtual vertical planes, at the anterior and posterior aspects of the sphenoidal spine, respectively, correspond to the posterior trunk of V₃ and middle meningeal artery, and the stylopharyngeal aponeurosis. The average length of sphenoidal spine was 8.5 ± 2.43 mm, and the distance from distal apex of the sphenoidal spine to the foramen ovale, foramen spinosum, and pICA were 10.82 ± 0.83 mm, 6.42 ± 0.52 mm, and 5.02 ± 0.54 mm, respectively.

CONCLUSIONS

The sphenoidal spine is a meaningful landmark for endonasal approaches to the ITF. Measurements and conceptualization of vertical planes prior and posterior to the sphenoidal spine are beneficial to better appreciate the anatomic relationships in the ITF.

Trends in the Management of Non-Vestibular Skull Base and Intracranial Schwannomas

The aim of this review is to analyze the latest trends in the management of non-vestibular skull base and intracranial schwannomas in order to optimize tumor control and quality of life. Non-vestibular cranial nerve schwannomas are rare lesions, representing 5–10% of cranial nerve schwannomas. Management decisions should be individualized depending on tumor size, location and associated functional deficits. Generally, large sized schwannomas exerting significant mass effect with increased intracranial pressure are treated surgically. In some cases, even after optimal skull base resection, it is not possible to achieve a gross total resection because tumor location and extent and/or to reduce morbidity. Thus, subtotal resection followed by stereotactic radiosurgery or fractioned radiotherapy offers an alternative approach. In certain cases, stereotactic radiosurgery or radiotherapy alone achieves good tumor control rates and less morbidity to gross total resection. Finally, given the slow growth rate of most of these tumors, observation with periodic radiographic follow-up approach is also a reasonable alternative for small tumors with few, if any, symptoms.

Combined Simultaneous Multiportal Approach via Minimally Invasive Transciliary and Endoscopic Endonasal Approaches for Tumors Invading Both the Skull Base and the Sinonasal Area

BACKGROUND

A combined transcranial and transfacial approach has long been the gold standard for surgical management of large tumors with sinonasal and skull base involvement. The extended endoscopic endonasal approach for such pathologies has its advantages, but it has flaws as well, such as anatomic limitations and more ponderous skull base reconstruction and thus higher risk of postoperative complications. Our primary technique for surgical treatment of these pathologies has been a combination of transfacial and minimally invasive transciliary supraorbital keyhole approaches. With the aim to further minimize invasiveness, potential complications, and unsatisfactory aesthetic outcomes during surgical treatment of large tumors invading both the sinonasal area and the skull base, we abandoned the transfacial approach and simultaneously combined the transciliary supraorbital keyhole approach with the endoscopic endonasal approach.

METHODS

The well-known microscope-assisted minimally invasive approach via a transciliary supraorbital keyhole craniotomy was combined with the endoscopic endonasal approach.

RESULTS

Six patients with different histologic types of tumors affecting the sinonasal area and the skull base were operated on. The mean operative time was 3 hours, there were no unexpected intraoperative or postoperative complications, and total tumor removal was achieved in each patient. None of the patients experienced complications associated with the surgery during follow-up.

CONCLUSIONS

Our combined simultaneous multiportal approach enables total tumor eradication with reduced operative time and is associated with minimal intraoperative and postoperative complications, low mortality rate, and excellent cosmetic results.

Endoscopic-Assisted Lateral Corridor to the Infratemporal Fossa: Proposal and Quantitative Comparison to the Endoscopic Transpterygoid Approach

Objective  This study was aimed to propose an expanded endoscopic-assisted lateral approach to the infratemporal fossa (ITF) and compare its area of exposure and surgical freedom with the endoscopic endonasal transptergyoid approach (EETA). Methods  Anatomical dissections were performed in five cadaver heads (10 sides). The ITF was first examined through the endoscopically assisted lateral corridor, herein referred to as the endoscopic-assisted transtemporal fossa approach (TTFA). After that, the EETA was performed and coupled with two sequential maxillary procedures (medial maxillectomy [MM], and endoscopic-assisted Denker's approach [DA]). Using the stereotactic neuronavigation, measurements of the area of exposure and surgical freedom at the foramen ovale were determined for the previously mentioned approaches. Results  Bimanual exploration of the ITF through the endoscopic-assisted lateral approach was achieved in all specimens. The DA (729 ± 49 mm ² ) provided a larger area of exposure than MM (568 ± 46 mm ² ; p <  0.0001). However, areas of exposure were similar between the DA and the TTFA (677 ± 35 mm ² ; p  = 0.09). The surgical freedom offered by the TTFA (109.3 ± 19 cm ² ) was much greater than the DA (24.7 ± 4.8 cm ² ; p <  0.0001), and the MM (15.2 ± 3.2 cm ² , p <  0.0001). Conclusion  The study demonstrates the feasibility of the proposed approach to provide direct access to the extreme extensions of the ITF. The lateral corridor offers an ideal working area in the posterior compartment of the ITF without crossing over important neurovascular structures. The new technique may be used alone in selected primary ITF lesions or in combination with endonasal approaches in pathologies spreading laterally from the nose or nasopharynx.

Endoscopic transorbital approach to anterolateral skull base through inferior orbital fissure: a cadaveric study

BACKGROUND

Endoscopic transorbital approach (eTOA) has been announced as an alternative minimally invasive surgery to skull base. Owing to the inferior orbital fissure (IOF) connecting the orbit with surrounding pterygopalatine fossa (PPF), infratemporal fossa (ITF), and temporal fossa, the idea of eTOA to anterolateral skull base through IOF is postulated. The aim of this study is to access its practical feasibility.

METHODS

Anatomical dissections were performed in five human cadaveric heads (10 sides) using 0-degree and 30-degree endoscopes. A stepwise description of eTOA to anterolateral skull base through IOF was documented. The anterosuperior corner of the maxillary sinus in the horizontal plane of the upper edge of zygomatic arch was defined as reference point (RP). The distances between the RP to the foramen rotundum (FR), foramen ovale (FO), and Gasserian ganglion (GG) were measured. The exposed area of anterolateral skull base in the coronal plane of the posterior wall of the maxillary sinus was quantified.

RESULTS

The surgical procedure consisted of six steps: (1) lateral canthotomy with cantholysis and preseptal lower eyelid approach with periorbita dissection; (2) drilling of the ocular surface of greater sphenoid wing and lateral orbital rim osteotomy; (3) entry into the maxillary sinus and exposure of PPF and ITF; (4) mobilization of infraorbital nerve with drilling of the infratemporal surface of the greater sphenoid wing and pterygoid process; (5) exposure of middle cranial fossa, Meckel's cave, and lateral wall of cavernous sinus; and (6) reconstruction of orbital floor and lateral orbital rim. The distances measured were as follows: RP-FR = 45.0 ± 1.9 mm, RP-FO = 55.7 ± 0.5 mm, and RP-GG = 61.0 ± 1.6 mm. In comparison with the horizontal portion of greater sphenoid wing, the superior and inferior axes of the exposed area were 22.3 ± 2.1 mm and 20.5 ± 1.8 mm, respectively. With reference to the FR, the medial and lateral axes of the exposed area were 11.6 ± 1.1 mm and 15.8 ± 1.6 mm, respectively.

CONCLUSIONS

The eTOA through IOF can be used as a minimally invasive surgery to access whole anterolateral skull base. It provides a possible resolution to target lesion involving multiple compartments of anterolateral skull base.

Evolution of transmaxillary approach to tumors in pterygopalatine fossa and infratemporal fossa: anatomic simulation and clinical practice

BACKGROUND

The endoscopic transnasal approach has been proven to have advantages on the removal of the tumors in pterygopalatine fossa (PPF) and infratemporal fossa (ITF). Herein, this study aimed to describe a modified approach for resection of the tumors in these areas, both in cadaveric specimen and clinical patients.

METHODS

The 20 adult cadaveric specimens and five patients with tumors in PPF and ITF were enrolled in this study. For the cadaveric specimens, ten were simulated anterior transmaxillary approach and ten were performed modified endoscopic transnasal transmaxillary approach. The exposure areas were compared between two groups and main anatomic structure were measured. Surgery was operated in the five patients with tumors of PPF and ITF to verify the experience from the anatomy. Perioperative management, intraoperative findings and postoperative complications were recorded and analyzed.

RESULTS

The modified endoscopic transnasal transmaxillary approach provided as enough surgical exposure and high operability to the PPF and ITF as the anterior transmaxillary approach did. The diameter of maxillary artery in the PPF was 3.77 ± 0.78 mm (range: 2.06-4.82 mm), the diameter of middle meningeal artery in the ITF was 2.79 ± 0.61 mm (range: 1.54-3.78 mm). Four patients who suffered schwannoma got total removal and one of adenocystic carcinoma got subtotal removal. The main complications were facial numbness and pericoronitis of the wisdom tooth. No permanent complication was found.

CONCLUSIONS

With the widespread use of neuroendoscopy, the modified endoscopic transnasal transmaxillary approach is feasible and effective for the resection of tumors located in PPF and ITF, which has significant advantages on less trauma and complications to the patients.

Neuroendoscopic Resection of Trigeminal Schwannoma in the Pterygopalatine/Infratemporal Fossa via the Transnasal Perpendicular Plate Palatine Bone or Transnasal Maxillary Sinus Approach

BACKGROUND

Both the pterygopalatine fossa (PPF) and the infratemporal fossa (ITF) lie outside the midline of the skull base. Lesions in the PPF or ITF include trigeminal schwannoma (trigeminal schwannoma, TS), which originates from the second or third branch of the trigeminal nerve (maxillary nerve or mandibular nerve). Due to their typically deep anatomic location, lesions in the PPF or ITF can be difficult to treat using traditional surgical approaches. In recent years, because of their advantages, which include the fact that they allow the problem to be observed close up, neuroendoscopic techniques are increasingly being applied in skull base surgery, especially in treatment of lesions around the midline of the base of the skull. This study aims to 1) evaluate the neuroendoscopic treatment of lesions in PPF or ITF via the transnasal palate bone perpendicular plate or transnasal maxillary sinus approach and 2) analyze the clinical significance of this approach.

METHODS

We retrospectively analyzed 3 cases of PPF TSs and 1 case of ITF TS treated between January 2015 and May 2017. All of the cases underwent neuroendoscopic resection of TSs located in the PPF via the nasal perpendicular plate palatine bone (or nasal maxillary sinus) approach.

RESULTS

Two cases of PPF TSs were characterized by a thin palate bone perpendicular plate due to oppressed absorption of the tumor. Therefore the endoscopic transnasal palate bone perpendicular plate approach was employed. Additionally, 1 case of PPF TSs and 1 case of ITF TS were resected via the transnasal maxillary sinus approach. All 4 patients received total resection under endoscopy and recovered well after their respective operations without cerebrospinal fluid leakage, although 1 patient experienced postoperative dry eye symptoms and 1 other patient showed no improvement in facial numbness before and after the operation.

CONCLUSIONS

Neuroendoscopic surgery performed via the transnasal perpendicular plate palatine bone or transnasal maxillary sinus approach has its own unique advantages in removing TSs in PPF and in ITF: Notably, the tumor can be exposed and dealt with under direct vision, which prevents damage to important structures, such as the internal carotid and maxillary nerves, while at the same time helping to achieve total removal of TSs. Furthermore, by adopting this approach versus traditional skull base surgery, postoperative trauma can be reduced significantly, which should be advocated for in this time of minimal invasive surgery.

Developmental Considerations in Pediatric Skull Base Surgery

Objectives  To review developmental surgical anatomy and technical nuances related to pediatric skull base surgery. Design  Retrospective, single-center case series with literature review. Setting  MD Anderson Cancer Center. Participants  Patients undergoing pediatric skull base surgery. Main Outcome Measures  Review developmental anatomy of the pediatric skull base as it relates to technical nuance of various surgical approaches and insight gained from a 25-year institutional experience with this unique patient population. Results  Thirty-nine patients meeting these criteria were identified over a 13-year period from 2003 to 2016 and compared to a previously reported earlier cohort from 1992 to 2002. The most common benign pathologies included nerve sheath tumors (11%), juvenile nasopharyngeal angiofibromas (9.5%), and craniopharyngiomas (4.8%). The most common malignancies were chondrosarcoma (11%), chordoma (11%), and rabdomyosarcoma (11%). Varied surgical approaches were utilized and were similar between the two cohorts save for the increased use of endoscopic surgical techniques in the most recent cohort. The most common sites of tumor origin were the infratemporal fossa, sinonasal cavities, clivus, temporal bone, and parasellar region. Gross total resection and postoperative complication rates were similar between the two patient cohorts. Conclusions  Pediatric skull base tumors, while rare, often are treated surgically, necessitating an in depth understanding of the anatomy of the developing skull base.

Combined Minimally Invasive Supraciliary and Transfacial Approach for Large Tumors with Skull Base and Sinonasal Involvement

BACKGROUND

Tumors invading both the anterior skull base and the sinonasal area have traditionally been accessed via largely invasive open craniofacial approaches. Minimally invasive extended endoscopic endonasal approaches have recently become increasingly available but have anatomical limitations and require incremental experience and thus high patient volume. Our objective was to assess the applicability of a novel combination of the minimally invasive supraciliary incision and the limited maxillofacial osteotomy as a combined surgical approach for large tumors invading both the anterior skull base and the sinonasal area.

METHODS

The well-established technique of supraciliary incision with a 2.5 × 3.0-cm craniotomy was combined for the first time with limited facial translocation approach.

RESULTS

This series involves 11 cases (female/male ratio 4:7; ranging in age from 6 to 61 years). Intracranial tumor propagation with intranasal and ethmoidal extension was detected in all patients. The pathologic diagnoses included adenocarcinomas, esthesioneuroblastoma, rhabdomyosarcoma, sinonasal papilloma, meningioma, and neurofibroma. The postoperative approach-related mortality rate was zero. No case of cerebrospinal fluid leak was detected. The 3-year survival rate was 70%.

CONCLUSIONS

The limited transfacial approach in combination with a supraciliary extension is associated with minimal mortality and morbidity and facilitates gross total tumor removal. We highly recommend this approach for the surgical treatment of large tumors invading both the anterior skull base and the sinonasal area, especially for those being out of indication for extended endoscopic endonasal surgery.

Nasal juvenile angiofibroma: Current perspectives with emphasis on management

Juvenile angiofibroma is an uncommon, benign, locally aggressive vascular tumor. It is found almost exclusively in young men. Common presenting symptoms include nasal obstruction and epistaxis. More advanced tumors may present with facial swelling and visual or neurological disturbances. The evaluation of patients with juvenile angiofibroma relies on diagnostic imaging. Preoperative biopsy is not recommended. The mainstay of treatment is resection combined with preoperative embolization. Endoscopic surgery is the approach of choice in early stages, whereas, in advanced stages, open or endoscopic approaches are feasible in expert hands. Postoperative radiotherapy (RT) or stereotactic radiosurgery seem valuable in long-term control of juvenile angiofibroma, particularly those that extend to anatomically critical areas unsuitable for complete resection. Chemotherapy and hormone therapy are ineffective. The purpose of the present review was to update current aspects of knowledge related to this rare and challenging disease. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1033-1045, 2017.

Osteoplastic Maxillotomy for Treatment of Neoplasms of the Nasopharynx and Infratemporal Fossa

Approaches to the infratemporal fossa and nasopharynx are difficult because of the anatomic complexity of these regions. We describe our experience with osteoplastic maxillotomy, with our own modifications, and evaluate oncological outcomes and postoperative quality of life. Ten patients underwent osteoplastic maxillotomy, 3 of whom had a diagnosis of malignancy, and 7 of whom had nasopharyngeal angiofibromas (NPAs). A Weber-Fergusson incision was made to develop facial flaps and preserve the vascularity of the maxilla. Osteotomies were performed through the facial aspects of the maxilla, on the orbital rims, and on the malar eminence for the medial variant of the procedure. The anterolateral variant involved descent of the temporalis muscle with preservation of the facial nerve, and a zygomatic osteotomy. Four craniotomies were done. Two patients had the medial variant of the procedure, and 8 had the anterolateral variant. The complications were transient and mild. The patients who had malignancies are alive with no disease, and there was 1 recurrence among the 7 patients with NPAs. We found excellent aesthetic results in 8 of the 10 patients, and no change in basic functions in 8 patients. Osteoplastic maxillotomy allows resection of massive NPAs with no significant bleeding. Resection of malignant lesions with good results is feasible.

Aggressive maxillofacial disassembly in skull base surgery

Objective

To review our favorable experience with maxillofacial disassembly for exposure and resection of tumors of the skull base.

Patients and Methods

This is a retrospective review of 31 patients from 1997 to 2005 treated by maxillofacial disassembly and includes 22 patients with midface disassembly and 9 patients with mandible with or without midface disassembly.

Results

Follow-up ranges from 2 weeks to 7 years: 23 of 31 patients are alive and disease free; 3 patients are alive with disease; 3 patients have died of distant metastasis. There were 14 complications in 12 (38.7%) patients; 13 of 14 complications were minor. One major complication (cardiovascular accident) resulted in the single postoperative mortality in this series.

Conclusion

Our technique of maxillofacial disassembly allows for tailored exposure of all regions of the anterolateral skull base with acceptable perioperative morbidity in appropriately selected patients. EBM rating: C-4

Surgical management of primary and secondary tumors in the pterygopalatine fossa

OBJECTIVE

This article describes a surgical approach that has been applied to managing primary tumors in the pterygopalatine fossa and secondary tumors involving the pterygopalatine fossa.

PATIENTS AND METHODS

The Barbosa approach was modified by adding a lateral incision in the mandibular gingivobuccal fold from the canine tooth to the retromolar area. This technique was applied to nine patients with primary and secondary tumors in the pterygopalatine fossa. All patients had been observed by clinical examinations, MRI, and CT examinations.

RESULTS:

This technique allowed a large, inferiorly based flap to be raised, which includes the parotid gland. The masseter and temporalis muscles were divided horizontally, and the ascending ramus of the mandible was osteotomied between the mandibular angle and the sigmoid notch and reflected to expose the tumor in the pterygopalatine fossa and maxillary sinus. We have applied this technique in 9 patients. Of the 9 patients in our study, 5 (55%) were male and 4 (45%) were female. The median age of the patients at the time of operation for primary and secondary tumors in the pterygopalatine fossa was 49.5 years (range, 19–66 years). Four of the 9 patients had primary tumors in the pterygopalatine fossa. One patient had a tumor in the pterygoaplatine fossa extending into the maxillary sinus, 2 patients had tumors occurring in the maxilla involving the pterygopalatine fossa, 2 patients had tumors from the deep lobe of the parotid gland to the pterygopalatine fossa, and 1 patient had extracranial meningioma. Nine patients have been followed up from 3 months to 9 years and 6 months, and 1 patient had recurrence 2 years and 2 months postoperatively.

CONCLUSION:

This technique is especially useful to tumors in the pterygopalatine fossa and tumors in the pterygopalatine fossa extending into the maxillary sinus.

Salvage Surgery for Locally Recurrent Nasopharyngeal Carcinoma—A 10-Year Experience

OBJECTIVE: To evaluate the result of salvage surgery for patients with primary recurrence of nasopharyngeal carcinoma (NPC) after radiation therapy.

STUDY DESIGN AND SETTING: Prospective cohort at a tertiary referral center.

PATIENTS AND METHODS: Thirty-eight consecutive patients with primary recurrence of NPC after radiation failure underwent salvage surgery for curative intention via the facial translocation approach from July 1993 to December 2002. The follow-up time ranged from 2 to 88 months. Twelve patients with intracranial and skull base invasion needed a combined neurosurgical approach. Eight patients had additional postoperative radiation therapy.

RESULTS: The actuarial 3-year survival and local control rate was 60% and 72.8%, respectively. Ten (83.3%) of 12 patients with intracranial and skull base invasion achieved local control. There was no surgical mortality, and the morbidity rate was only 13.2%.

CONCLUSION AND SIGNIFICANCE: The results of this study reveal better outcome of salvage surgery than that of most published literature of reirradiation for recurrent NPC. With the adequate exposure provided by the facial translocation approach, an integrated concept of skull base surgery, and the collaboration of neurosurgeons, we can extend our surgical indications of salvage surgery and resect many advanced lesions with acceptable mortality and morbidity.

Modified Facial Translocation Approach in a One-Month Old With a Skullbase Tumor

The authors present a patient of a neonate with a skull base extragonadal germ cell tumor requiring a modified facial translocation approach for resection. A 1-week-old female presented with right proptosis, eyelid edema, and nasal obstruction. Imaging revealed a 3-cm right-sided skull base mass involving the right maxillary, ethmoid, sphenoid sinuses, orbit, infratemporal fossa, and cavernous sinus via skull base erosion. The lesion was refractory to chemotherapy and required surgical excision. A modified facial translocation approach with preservation of anterior maxillary bone vascularization was used to remove the tumor, which was found to be teratoma with yolk-sac features. The patient tolerated surgery well and was noted to have minimally affected facial skeleton growth at 2-year follow-up. This modified facial translocation approach allowed safe access to this anterior skull base tumor with acceptable morbidity and mild facial growth effects so far.

Volumetric Analysis of Nasopharyngectomy via Endoscopic Endonasal, Maxillary Transposition, and Lateral Temporal-Subtemporal Approaches

OBJECTIVE

This project develops a computer model that allows volumetric analysis of the exposure afforded by an endonasal-endoscopic approach, maxillary transposition, and lateral temporal-subtemporal approaches during a nasopharyngectomy. The model will demonstrate idiosyncracies of these approaches, including sacrifice of normal tissues, ease of instrumentation, and gate of entry.

SUBJECTS AND METHODS

Computed tomographic scans of an anatomic specimen were used to create computer simulations of the endoscopic endonasal, maxillary transposition, and lateral temporal-subtemporal approaches for T1and T4 nasopharyngeal carcinoma; therefore, allowing assessment of their surgical corridor using Intuition, a software that allows a semiautomated computerized segmented volumetric analysis.

RESULTS

The smallest volumes of tissue mobilization or removal were observed during the endoscopic-endonasal nasopharyngectomy. The volumes of tissue mobilization for the maxillary transposition approach were higher than those of lateral temporal-subtemporal approaches.

CONCLUSIONS

This model adds to our understanding of select surgical corridors to the nasopharynx. It suggests that an endoscopic-endonasal approach requires less manipulation or resection of smaller volumes of normal tissue to expose a nasopharyngeal tumor than the lateral temporal-subtemporal and maxillary transposition approaches. It also, however, requires instrumentation through a smaller entry gate implying greater difficulty. Nonetheless, these factors should not be construed as superiority of one approach over the other. Factors that are important in the choosing of the surgical approach, such as surgeon's training and experience, invasion of neurovascular structures and method of reconstruction are not considered in this model.

The combined endonasal and transoral approach for the management of skull base and nasopharyngeal pathology: a case series

The posterior skull base and the nasopharynx have historically represented technically difficult regions to approach surgically given their central anatomical locations. Through continued improvements in endoscopic instrumentation and technology, the expanded endonasal approach (EEA) has introduced a new array of surgical options in the management of pathology involving these anatomically complex areas. Similarly, the transoral robotic surgical (TORS) approach was introduced as a minimally invasive surgical option to approach tongue base, nasopharyngeal, parapharyngeal, and laryngeal lesions. Although both the EEA and the TORS approach have been extensively described as viable surgical options in managing nasopharyngeal and centrally located head and neck pathology, both endonasal and transoral techniques have inherent limitations. Given these limitations, several institutions have published feasibility studies with the combined EEA and TORS approaches for a variety of skull base and nasopharyngeal pathologies. In this article, the authors present their clinical experience with the combined endonasal and transoral approach through a case series presentation, and discuss advantages and limitations of this approach for surgical management of the middle and posterior skull base and nasopharynx. In addition, a presentation is included of a unique, simultaneous endonasal and transoral dissection of the nasopharynx through an innovative intraoperative setup.

Endoscopic versus Open Approach to the Infratemporal Fossa: A Cadaver Study

Introduction Various lateral and anterior approaches to access the infratemporal fossa (ITF) have been described. We provide our observations regarding the endoscopic transpterygoid and preauricular subtemporal approaches, listing their respective advantages and limitations through cadaveric dissection. Methods A cadaver study was performed on five adult specimens. An endoscopic transpterygoid approach to the ITF was completed bilaterally in three specimens, and an open preauricular ITF approach was performed bilaterally in two specimens. Results After completing the cadaveric dissections, we studied differences between the endoscopic transpterygoid approach and open preauricular subtemporal approaches in regard to exposure and ease of dissection of different structures in the ITF. Conclusions In comparison with a lateral approach, the endonasal endoscopic transpterygoid approach provides better visualization and more direct exposure of median structures such as the nasopharynx, eustachian tube, sella, and clivus. We concluded that the endoscopic transpterygoid approach can be utilized to resect benign lesions and some select group of malignancies involving the infratemporal and middle cranial fossae. Open approaches continue to play an important role, especially in the resection of extensive malignant tumors extending to these regions.

Orbito-rhino-antro access osteotomy for anterior skull base lesions

Even with advent of endoscopic assisted surgeries the access osteotomy plays an important role for accessing the pathological lesions of anterior skull base since beginning of the era of surgery. This report introduces the orbito-rhino-antral access osteotomy for the removal of juvenile nasio angio fiboma extending in to the cranial base. This osteotomy provides good access to the lesion with lesser morbidity and without hampering the occlusion as in lefort osteotomies. It is safe, easy and faster to perform. Osteotomised segment is easy to replace and gives ease for the surgeon to access without any hindrance. The osteotomised segment act as free graft and there are no complications postoperatively even after 48 mnth of follow-up.

Endoscopic endonasal approaches to infratemporal fossa tumors: a classification system and case series

OBJECTIVES/HYPOTHESIS

To propose a clinically applicable anatomic classification system describing three progressive endoscopic endonasal approaches (EEAs) to the infratemporal fossa (ITF) and their potential sequelae. Overall feasibility and outcomes of these approaches are presented through a consecutive case series.

STUDY DESIGN

Description of classification system for EEAs to the ITF and case series.

METHODS

A classification system of EEAs to ITF tumors was created based on the senior author's clinical experience and cadaveric dissection. A retrospective chart review of 21 child and adult patients with primary ITF tumors treated by these approaches from 2008 to 2012 at a tertiary-care academic medical center was conducted.

RESULTS

Three progressive EEAs to ITF tumors were defined: 1) a transpterygopalatine fossa approach, 2) a transmedial pterygoid plate approach, and 3) a translateral pterygoid plate approach. Twenty-one patients treated with these approaches were identified consecutively, with a mean age of 44.2 years (range, 11-79 years). Tumors primarily involving the pterygopalatine fossa and not the ITF were excluded. Pathology included three advanced juvenile nasopharyngeal angiofibromas, three adenoid cystic carcinomas, two recurrent inverted papillomas, two trigeminal schwannomas, and 11 other diverse skull base pathologies. No intraoperative or postoperative complications occurred, with a mean follow-up of 21.5 months (range, 1-55 months). Expected potential sequelae such as V2/palatal numbness, Eustachian tube dysfunction, and trismus occurred in 10/21 patients.

CONCLUSIONS

EEAs to ITF tumors are technically feasible with low risk of complications for well-selected patients. The proposed classification system is useful for anticipating potential sequelae for each approach.

Modified midfacial translocation for access to ventral skull base tumours

OBJECTIVE

To describe our technical modifications of midfacial translocation for access to the nasopharynx, and anterior, central and lateral skull base.

DESIGN

Retrospective chart review of a prospective case series.

SETTING

Department of Otolaryngology-Head and Neck Surgery, Aberdeen Royal Infirmary, Scotland, UK.

METHODS

Along with demographics, other parameters studied were adequacy of exposure, completeness of resection, aesthetic outcome and complications. Our main outcome measures included adequacy of exposure, partial or total resection of tumour, aesthetic outcome, and complications related to surgical technique.

RESULTS

A total of 48 patients underwent modified midfacial translocation at our institution for nasopharyngeal, parapharyngeal, and anterior, central and lateral skull base tumours. In all cases, the exposure was deemed to be adequate. Two patients developed wound dehiscence in previously irradiated fields. Other incisions healed very well and the aesthetic outcome was regarded as satisfactory.

CONCLUSION

Modified midfacial translocation is based on the principle of temporary craniofacial disassembly for access to the skull base. Our modifications offer adequate access and a better aesthetic outcome. All incisions are placed through the aesthetic sub units of the nose with preservation of the lip. Preservation of the bony piriform aperture prevents airway compromise.

Quantitative study on endoscopic endonasal approach to the posterior sino-orbito-cranial interface: implications and clinical considerations

The posterior sino-orbito-cranial interface is a critical area in the skull base since it represents a gateway to deeper vital regions. Quantification of the surgical freedom for any given point/area is an objective method for comparing in a reproducible way different surgical approaches. Three freshly injected cadaver heads (six sides) were dissected under the magnetic navigation control system. The surgical freedom (SF) and the angle of attack of fixed target points were determined from the ipsilateral nasal fossa, from the contralateral nasal fossa (after posterior septectomy), and after an anteromedial maxillotomy (according to the Denker procedure). The mean pre-operative SF value resulted to be 403.07 ± 102.73 mm(2) for the ipsilateral nostril, increasing by 126.97 % for the binostril approach, by 118.45 % for the monolateral nostril approach after anteromedial maxillotomy, and by 310.48 % for the binostril approach after bilateral anteromedial maxillotomy. Laterally extended lesions require an anteromedial maxillotomy, while more medially located lesions can be managed by means of a posterior septectomy. When addressing the posterior sino-orbito-cranial interface, the transnasal binostril approach and anteromedial maxillotomy both increase the SF. The choice between them depends on exact position, relationship and clinical behaviour of the lesion to treat.

Combined transoral robotic surgery and endoscopic endonasal approach for the resection of extensive malignancies of the skull base

BACKGROUND

Oncologic resection of the clivus, nasopharynx, craniovertebral junction, and infratemporal fossa is a challenging endeavor because of their complex and protected anatomy. Our goals were to design a cadaveric model and identify advantages and limitations of combining the transoral robotic surgery (TORS) and endoscopic endonasal approach (EEA) techniques.

METHODS

Cadaveric specimens were dissected using a da Vinci surgical robot and endoscopic endonasal instruments in a fashion that mimicked our operating room environment. We then applied these techniques clinically.

RESULTS

EEA was performed to provide a detailed dissection of the infratemporal fossa, nasopharynx, posterior skull base (clivus), and craniovertebral junction. Using TORS, we dissected the parapharyngeal space, infratemporal fossa, and nasopharynx below the eustachian tube, which represented a transition zone that delineated the most effective resection field of each approach.

CONCLUSIONS

TORS and EEA seem to be complementary techniques; thus, their combined use seems advantageous for selected advanced tumors in these complex areas.

Surgical results of an endoscopic endonasal approach for clival chordomas

BACKGROUND

The surgical approaches for clival chordomas remain controversial, although the extent of resection is one of the most important factors for long survival rates. Recently an endoscopic endonasal approach in good collaboration with otolaryngologists has attracted major attention as a surgical approach for clival chordomas. We describe our experience with the endoscopic endonasal approach and provide a review of the literature.

METHODS

Between 2008 and 2011, six operations were performed via the endoscopic endonasal approach for clivus chordomas. The mean tumor size was 35 mm in diameter. The tumor location was mainly from the upper to middle clivus. The tumor extended into the cavernous sinus in five cases and intradurally in three cases. A binostril approach was performed in four cases, while a one nostril approach was performed in two cases.

RESULTS

Gross total removal was achieved in three cases. The analysis of cases with incomplete resection suggested that residual tumors were observed epidurally and subdurally. The residual on the epidura was observed from the posterior clinoid to the posterior compartment of the cavernous sinus. On the other hand, the residual on the subdural was observed behind the upper part of the pituitary gland. There was no postoperative cerebrospinal fluid (CSF) leakage using vascularized nasoseptal flaps in any of the cases.

CONCLUSIONS

The endoscopic endonasal transclival approach allows an appropriate extent of resection with acceptable complication rates in comparison with other approaches. In our series, the accomplishment of gross total removal was associated with the relationship between the tumors and surrounding structures, such as the pituitary gland and the cavernous portion of the intracranial carotid artery (ICA).

Morbidity profile and functional outcome of modified facial translocation approaches for skull base tumors

The primary objective of this study was to evaluate morbidity associated with facial translocation approaches for skull base and results of various technical modifications. Forty consecutive patients who underwent facial translocation approaches for accessing skull base tumors from July 2005 to June 2010 were included in this study. There were 25 patients who underwent standard facial translocation, 4 patients medial mini, and 11 patients underwent extended facial translocation. Thirteen patients had benign disease and 27 patients had malignant disease. Resection was R0 in 36 and R1 in 4 patients. Most patients had acceptable cosmetic results. None of the patients had problems related to occlusion or speech and swallowing. The commonest complication observed was nasal crusting in 16 patients. Grade 2 trismus and exposure of mini plate was seen in three patients. Two patients developed necrosis of translocated bone. Three patients developed palatal fistula before modification of palatal incision. Facial translocation provides a satisfactory access for adequate clearance of skull base tumors with satisfactory aesthetic and functional results. With modifications of the surgical technique and implementation of new surgical tools, the morbidity of facial translocation approaches will continue to decrease.

Total maxillary swing approach to the skull base for advanced intracranial and extracranial nasopharyngeal angiofibroma

The main objective of surgical approaches to the anterior and anterolateral skull base is to have maximum exposure so injury to important structures is avoided, and surgical complications are reduced. At our institution, we used total maxillary swing (TMS) to approach the anterior and anterolateral skull base for resection of both malignant and benign tumors. We modified some of the techniques described in TMS to avoid complications encountered previously. The purpose of this article was to present the usefulness of TMS for maximum exposure of the anterior and anterolateral skull base using advanced nasopharyngeal angiofibroma (NPA) as the reference disease.We retrospectively reviewed 16 patients who underwent excision of NPA by TMS from 2005 to May 2011. The operative techniques, operative findings, postoperative complications, and follow-up records were reviewed and analyzed.Of the 16 cases of NPA, 5 had intracranial extensions. All had lateral extensions to the pterygopalatine fossa. The pterygoid base was explored in all cases. In 10 cases, the tumors were present in the spongy bone of the pterygoid bases, whereas in 6 cases, the base of the pterygoids was eroded and floating. In all cases, the tumor was completely removed. Complications encountered previously were avoided by the modifications to TMS. Complications encountered because of extensiveness of the tumor were easily managed. No patients had any recurrence until now.Total maxillary swing provides maximum exposure to the anterior and anterolateral skull base for complete removal of the tumors in those areas with minimal complications.

Skull base tumor volume and surgical margins: a pilot study

The relationship between preoperative assessment of tumor volume and oncologic adequacy of surgical margins was studied retrospectively. Our hypothesis was that the risk of inadequate, or positive, margins would rise with increasing tumor volume and that this would adversely affect survival. We anticipated that limitations of surgical approaches used until 1988 would be reflected in an increasing proportion of positive margins with increasing tumor volume. We conducted a pilot study of 25 patients with malignant tumors of the anterolateral cranial base operated on at the University of Pittsburgh Center for Cranial Base Surgery between 1987 and 1988. Preoperative computed tomography assessment of tumor volume was performed in all patients, and correlation between tumor volume, surgical margins, and survival was examined. Follow-up interval averaged 31.7 months. Twelve histologic tumor types were represented, with squamous cell carcinoma the most common (eight patients [32%]). Tumor volume ranged from 0.9 to 390 cc, with a median of 48 cc. Based on a median split of tumor volumes, patients were classified as high volume (more than 48 cc) or low volume (less than 48 cc). Of patients in the high volume group, 92% were found to have positive surgical margins, whereas only 50% of patients in the low volume group had positive margins. Analysis of the effect of tumor volume and surgical margins on survival was limited by sample size constraints, but both high-tumor volume and positive margins tended to reduce patient survival (0.07 < p 0.10).

Quantitative evaluation of transtemporal and facial translocation approaches to infratemporal fossa

OBJECTIVE

To compare the extent of exposure and surgical maneuverability provided by facial translocation and transtemporal approaches for access to the infratemporal fossa and anterolateral skull base.

MATERIALS AND METHODS

Surgical procedures were performed on five fresh frozen adult cadavers (ten sides) with no known pathology. Facial transfacial approaches with and without a mandibulotomy and transtemporal approaches were evaluated. OBJECTIVE measures were (1) the distance from the surgical plane to designated anatomic landmarks and (2) the surgical angle of exposure.

RESULTS

Distances from the surgical plane to the anatomic reference points were comparable for most of the access procedures (3 to 6 cm). The extended midfacial translocation and bilateral facial translocation approaches did, however, provide a shorter operative distance (1 to 3 cm) for access to the infratemporal fossa and contralateral structures, respectively. The transtemporal approaches facilitate a better angle of exposure (74 to 84 degrees) to the petrotemporal region, while the transfacial approaches were superior for access to the infratemporal structures.

CONCLUSIONS

Based on the results, we propose a clinical algorithm for selecting a surgical approach based on the position and extent of an infratemporal or petrotemporal lesion.

Salvage surgery for recurrent nasopharyngeal carcinoma

OBJECTIVES

To present our experience of salvage surgery for recurrent nasopharyngeal carcinoma after primary treatment by radiotherapy.

PATIENTS AND METHODS

Eleven of 25 patient treated for nasopharyngeal carcinoma between 1990 and 2003 with radiotherapy had either residual or recurrent disease and underwent salvage surgery. The type C infratemporal fossa approach was used to access residual tumor. The patients' progress was followed by clinical examination and interval magnetic resonance scans.

OUTCOME MEASURES AND RESULTS

The results were analyzed in terms of morbidity and oncological outcome; patients were recorded as NED (no existing disease), AWD (alive with disease), and DOD (died of disease). A disease-free survival rate of 72% was achieved in the salvage surgery group of patients and an overall disease-free survival rate of 56% applied to the initial cohort of 25 patients, following both the single mode and combined treatment.

CONCLUSION

Salvage surgery is feasible for patients with recurrent nasopharyngeal carcinoma and may be achieved with minimal morbidity using the type C infratemporal fossa approach.

Lateral skull base surgery: the otology group experience

Lateral skull base surgery has remained the surgical frontier of new developments in the treatment of lesions heretofore difficult to access. Examination of surgical results stimulates technical innovation and provides an intervention risk-benefit ratio assessment for particular lesions useful in management planning. With this in mind, we report the updated collective experience with lateral skull base surgery at the Otology Group over the past 20 years. Two hundred ninety-eight patients underwent surgical intervention for lateral skull base lesions. In 81 patients these lesions were malignant; in 217, benign. Of the benign lesions, 165 were glomus tumors: 139 glomus jugulare, 19 glomus vagale, and 7 glomus tympanicum. The remainder comprised 21 menigniomas, 14 neuromas, two neurofibromas, and a small group of much rarer entities. The philosophy of surgical approach, results, and follow-up are discussed.

Tumors of the infratemporal fossa

Neoplastic processes involving the infratemporal fossa may originate from the tissues in the region, but more often are the result of extension from neighboring structures. Metastatic lesions located in the region are rarely encountered. Because of its concealed localization, tumors may remain unnoticed for some time. Clinical signs and symptoms often arise late, are insidious, and may be mistakenly attributed to other structures. The close proximity of the area to the intracranial structures, the orbit, the paranasal sinuses, the nasopharynx, and the facial area demands careful planning of surgical excision and combined procedures may be called for. Modern imaging techniques have made three-dimensional visualization of the extent of the pathology possible. Treatment depends on the histopathology and staging of the tumor. Several surgical approaches have been developed over the years. Radical tumor excision with preservation of the quality of life remain the ultimate goal for those tumors where surgery is indicated. Experience over a decade with various pathologies is presented.

Open-door maxillotomy approach for lesions of the clivus

The transpalatal route to the clival region has been used to approach both extradural and intradural lesions. Classic transpalatal surgery, however, entails a partial splitting of the soft palate or some form of palatal retraction, which leaves behind a bony palate that hinders surgical exposure. When necessary, operative exposure can be enhanced by an open-door maxillotomy approach that uses a combination of a Le Fort I osteotomy of the maxilla and a paramedian sagittal split of the hard palate. The nasal septum is translocated to create a wide contiguous oronasal aperture through which the clival region can be reached unobstructed. This technique was used in three patients. No significant complications were observed in any patient. Features of this extended transpalatal approach, including indications and adjunctive measures to minimize potential complications, are discussed.

Transorbital approach to infratemporal fossa: novel technique

OBJECTIVE

To present a conservative surgical approach, via the transorbital route, for selected cases of infratemporal fossa involvement or inferolateral orbital tumours extending to the infratemporal fossa.

DESIGN

Case series report.

SETTING

Department of ENT, CSM Medical University (King George Medical College), Lucknow, India.

PARTICIPANTS

One patient.

MAIN OUTCOME MEASURES

Operative feasibility, intra-operative access, post-operative morbidity and cosmesis.

RESULTS

This novel and relatively conservative technique provides excellent exposure in selected cases of infratemporal fossa involvement and has minimal post-operative morbidity. Cosmesis is excellent, as osteotomy is not required and scarring is minimal. There is no risk of trismus, Vth or VIIth cranial nerve injury, or cerebrospinal fluid leakage, and haemostasis is easily achieved.

CONCLUSION

Classical, open approaches to the infratemporal fossa involve considerable morbidity, while conservative approaches have their limitations. Diagnostic uncertainty over a small infratemporal fossa mass (perhaps an extension from an inferolateral orbital tumour) is an uncommon clinical challenge. The transorbital approach described is suited to benign and early malignant tumours, and has excellent results when combined with orbital exenteration (if needed). This paper discusses this approach's technical details and feasibility in different clinical situations, and compares it with other infratemporal fossa approaches.

Fully endoscopic transnasal approach to the jugular foramen: anatomic study and clinical considerations

BACKGROUND AND IMPORTANCE

To describe a transnasal endoscopic route to the jugular foramen and the endoscopic anatomy of the infratemporal fossa.

CLINICAL PRESENTATION

Endoscopic transnasal dissection of the infratemporal fossa was performed in 3 injected fresh heads (1 head only in arteries and 2 heads in arteries and veins). Two other double-injected specimens were dissected externally (2 of them side laterally and 1 anteriorly) to compare the different views and better understand the 3-dimensionality of the region.Detailed endoscopic anatomy of the infratemporal fossa was clearly observed. The realization of a septal and posterior maxillary window allows surgeons to gain space to the jugular foramen. The ability to manage the vessels, especially the veins, and identify the muscles is mandatory. The fundamental role of the vidian canal in targeting the anterior genu of the internal carotid artery is confirmed. The role of the maxillary and mandibular branches of the trigeminal nerve and the eustachian tube in this kind of approach is critical.

CONCLUSION

A fully transnasal endoscopic route to the jugular foramen is feasible. The most important landmark for this kind of approach is the eustachian tube.

Quantification of clival and paraclival exposure in the Le Fort I transmaxillary transpterygoid approach: a microanatomical study

OBJECT

The authors describe a modified Le Fort I maxillotomy with medial and posterior antrectomy and removal of the pterygoid plates, aimed at improving the lateral surgical exposure during open transmaxillary surgery for pathological conditions involving the clivus. A cadaveric microanatomical study was conducted to compare the planimetric exposures allowed by the transmaxillary transpterygoid (TMTP) approach and the standard Le Fort I maxillotomy (STM).

METHODS

Six cadaveric specimens that had been fixed with glutaraldehyde and injected with latex were dissected to obtain morphometric measurements after both TMTP and STM approaches. The anatomical areas exposed by the surgical approaches were calculated using ImageJ 1.37a software.

RESULTS

As expected, the TMTP approach allowed for a greater surgical exposure, with an incremental area exposed ranging from 4.9 to 7.6 cm(2) (mean ± standard deviation 6.4 ± 1.2 cm(2), 95% CI 5.4-7.4 cm(2)). The amount of additional anatomical area visualized, as recorded as a percentage increase after the TMTP approach when compared with the STM approach, ranged from 83 to 109% (mean 99%).

CONCLUSIONS

The lateral surgical exposure allowed by the STM approach is limited by the pterygoid plates. The TMTP approach significantly improves the exposure of the anatomical regions lateral to the clivus, allowing access to the pterygopalatine and medial infratemporal fossae. In comparison with the STM, the TMTP approach allows for a surgical exposure that is nearly double. The authors conclude that the TMTP approach provides a significant improvement in the surgical exposure of the lateral paraclival areas, when compared with the STM approach.

Nasal downward swing approach coupled with the facial dismasking flap

OBJECTIVE

For the purpose of an en bloc resection with sufficient margins, a wide surgical field is necessary. We have reported on the application of a facial dismasking flap for removals of craniofacial lesions in order to provide a better surgical field with less morbidity. In this paper, we are introducing a new method, which is called the "nasal downward swing approach".

METHODS

This approach is a modification of the facial dismaking flap, which elevates the nasal bone along with the facial skin.

RESULTS

This approach offers an extremely wide surgical field on the facial front, especially the nasal cavity, while keeping scarring or facial paresis down to a bare minimum.

CONCLUSION

This approach helps to preserve the entire shape of the nasal bone in particular, therefore, a good surgical option for pediatric patients.

Endoscopic anatomy of the petrous segment of the internal carotid artery

BACKGROUND

Exposure of the petrous (C2) segment of the internal carotid artery (ICA; petrous carotid) is necessary to treat lesions that have spread from the intracranial space or adjacent sinonasal region. Recent advancements in endonasal-endoscopic approaches to the anterior skull base raise the possibility of extending these approaches beyond the sinonasal cavity. In this cadaveric study, we evaluate the feasibility and extent of exposure of the petrous carotid artery via a combined endoscopic endonasal approach.

METHODS

Endoscopic dissection was performed in four formalin-fixed cadaver heads (eight sides). An endoscopic, endonasal, transmaxillary approach was used to identify the cervical and petrous carotid artery.

RESULTS

With the endoscopic endonasal, Caldwell-Luc approach, we could visualize the ventral petrous bone after dissecting the contents of the pterygopalatine fossa and infratemporal fossa. Careful dissection allowed exposure of the petrous carotid artery from the upper cervical carotid to the foramen lacerum.

CONCLUSION

In this cadaveric study using an endoscopic endonasal approach for exposure of the petrous carotid artery, combination with the transmaxillary-transpterygopalatine-transinfratemporal approaches permitted exposure of the ventral portion of the artery. The anatomy presented will assist experienced endoscopic skull base surgeons in the removal of lesions involving the ventral skull base.

Surgery for clival lesions: open resection versus the expanded endoscopic endonasal approach

OBJECT

Clival lesions pose significant challenges with regard to their surgical management. The expanded endoscopic endonasal (EEE) approach is a promising minimally invasive technique for lesions of the central skull base. The authors' aim in the current paper was to discuss the surgical treatment of clival lesions and to present the technical details, indications, and limitations of the EEE approach. Data from a recent endoscopically treated group will be compared with findings in a previous cohort of patients treated via classic open anterior and lateral approaches.

METHODS

Since June 2005, 17 patients with clival lesions underwent surgery via the EEE approach. Suitable candidates were chosen according to lesion characteristics, clinical parameters, and surgical goals. Neurological outcomes, Karnofsky Performance Scale scores, the extent of lesion resection, and complications were evaluated among these patients. Eighteen percent of the patients in the endoscopic group presented with recurrent disease. Another series of 43 patients, who had undergone resection of clival lesions via an anterior (rhinotomy, maxillectomy, microscopic transsphenoidal surgery, or transoral surgery) or lateral (pterional, frontoorbitozygomatic, or combined suprainfratentorial retrosigmoid) approach, was similarly reviewed. Twenty-three of these patients (53%) presented with recurrent disease and thus had undergone prior surgery.

RESULTS

Following the EEE approach, 11 (79%) of 14 patients who had presented with neurological symptoms experienced improvement, and gross-total resection was achieved in 59% of the patients and subtotal removal in 41%. Complications included CSF leakage (24%), tension pneumocephalus (6%), and intracranial hematoma (6%). The patient with the latter complication was the only one who experienced permanent neurological worsening. In the open resection group, neurological worsening occurred in 33% of the patients (14 of 43). Total and grosstotal removals were achieved in 84% of patients and subtotal removal in 14%.

CONCLUSIONS

The EEE approach has been shown to be a safe and effective technique for the resection of clival lesions with limited lateral extension. The choice of surgical approach must be tailored according to both patient and tumor characteristics. Although the 2 patient series featured in this paper are not comparable-because of a selection bias-higher rates of neurological morbidity and total and gross-total resections were observed in the open resection group. Given the long survival of some patients, the EEE approach should be favored whenever reasonable.

Infratemporal metastasis from occult follicular thyroid carcinoma

An extremely rare case that has not been reported before is described in which metastasis of a follicular carcinoma of the thyroid is resected from the infratemporal fossa. The patient had not been diagnosed of this thyroid pathology. She underwent a left subtemporal preauricular approach, but after this, she had another subtemporal preauricular approach with total thyroidectomy, a facial translocation by degloving, and an endoscopic surgery, because of a local recurrence, and a sella turcica and sphenoidal sinus metastasis. Six years after this, the patient was free of recurrence. Surgical excision of metastatic thyroid lesions may be the only effective treatment but always followed by suppression therapy and whole-body iodine I 131 internal radiation. Stereotactic radiosurgery is a feasible option to treat skull base metastasis of this kind of tumor.

Anterior clivectomy: surgical technique and clinical applications

OBJECT

Midline clival lesions, whether involving the clivus or simply situated anterior to the brainstem, present a technical challenge for adequate exposure and safe resection. The authors describe, as a minimally invasive technique, an anterior clivectomy performed via an expanded transsphenoidal approach coupled with the use of a neuronavigation on mobile head and endoscopic-assisted technique. Wide and direct exposure, with the ability to resect extra- and intradural tumors, was achieved without mortality and with a low rate of complications.

METHODS

Cadaveric dissections were performed to outline the landmarks and measure the window that is created by resecting the clivus anteriorly. The technique was used in 43 patients to resect tumors located at or invading the clivus. The initial exposure of the clivus was obtained via the sublabial transsphenoidal approach. The wall of the anterior maxilla, often on 1 side, was removed to allow a wide side-to-side opening of the nasal speculum. Using neuronavigation, the authors made clivectomy windows by drilling the clivus between anatomical landmarks. Bilateral intraoperative neurophysiological monitoring was used (somatosensory evoked potentials, brainstem auditory evoked responses, and cranial nerves VI-XII).

RESULTS

Of the 43 patients, 26 were female and 17 were male, and they ranged in age from 3.5 to 76 years (mean 41.5 years). Thirty-eight patients harbored a chordoma and 5 a giant invasive pituitary adenoma. Gross-total resection of the tumor was achieved in 34 cases (79%). Nine patients (21%) had residual tumor unreachable through the anterior clivectomy, and this required a second-stage resection. Four patients developed new transient extraocular movement deficits. One patient developed a permanent cranial nerve VI palsy. Twenty-seven patients with chordoma underwent postoperative proton-beam radiotherapy. Tumor recurred in 19% of these cases. In 3 patients a cerebrospinal fluid leak developed during hospitalization and was treated successfully. Two other patients presented with a delayed cerebrospinal fluid leak after radiotherapy. Only 1 patient, who had previously undergone Gamma Knife surgery, experienced postoperative hemiparesis.

CONCLUSIONS

A complete anterior clivectomy via a simple extension of the transsphenoidal approach allows the surgeon access to different lesions involving the clivus or situated anterior to the brainstem. The exposure is similar to that provided by more extensive transfacial approaches. Instrument manipulation is easy. Neuronavigation, endoscopy, and intraoperative monitoring are easily incorporated and enhance the capability and safety of this approach.