Endoscopic Endonasal Interdural Middle Fossa Approach to the Maxillary Nerve: Anatomic Considerations and Surgical Relevance

Abstract BACKGROUND: The maxillary nerve (V2) can be approached via the open middle fossa approach. OBJECTIVE: To delineate the anatomy of V2 and its specific segments with respect to the endonasal landmarks. We present the endoscopic endonasal interdural middle fossa approach to V2 and its potential application for the treatment of perineural spread in sinonasal/skull base tumors. METHODS: Five human head silicon-injected specimens underwent bilateral endoscopic endonasal transpterygoid approaches. V2 prominence and the maxillary strut were identified in the lateral recess along with paraclival carotid protruberance. The regions superior and inferior to V2 corresponding to the anteromedial and anterolateral triangles of the middle fossa were exposed. RESULTS: V2 can be classified into 3 segments: interdural (from the Gasserian ganglion to the proximal part of the maxillary strut), intracanalicular (corresponding to the anteroposterior length of the maxillary strut), and pterygopalatine (distal to the maxillary strut and the site of its divisions). Endonasally, the average length of the interdural and the intracanalicular segments were approximately 9 and 4.4 mm, respectively. V2, following its division distal to the maxillary strut, was successfully dissected off the middle fossa dura and transected just distal to the Gasserian ganglion. CONCLUSION: Endonasally, the interdural segment can be safely mobilized between the periosteal and meningeal dural layers while ensuring the integrity of the middle fossa dura. This allows transection of infiltrated V2 to facilitate tumor resection without entering the intradural/arachnoidal space. Posteriorly, this is limited by the Gasserian ganglion and superomedially by the dural envelope surrounding the cavernous sinus and the paraclival carotid artery.

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Extended middle fossa approach to lateralized pontine cavernomas in children

Journal of Neurosurgery Pediatrics ◽

10.3171/2017.10.peds17381 ◽

2018 ◽

Vol 21 (4) ◽

pp. 384-388 ◽

Cited By ~ 4

Author(s):

Robert C. Rennert ◽

Reid Hoshide ◽

Mark Calayag ◽

Joanna Kemp ◽

David D. Gonda ◽

...

Keyword(s):

Trigeminal Nerve ◽

Internal Auditory Canal ◽

Csf Leak ◽

Geniculate Ganglion ◽

Gasserian Ganglion ◽

Middle Fossa ◽

Cavernous Malformations ◽

Middle Fossa Approach ◽

Cerebellar Artery ◽

Mandibular Branch

OBJECTIVETreatment of hemorrhagic cavernous malformations within the lateral pontine region demands meticulous surgical planning and execution to maximize resection while minimizing morbidity. The authors report a single institution’s experience using the extended middle fossa rhomboid approach for the safe resection of hemorrhagic cavernomas involving the lateral pons.METHODSA retrospective chart review was performed to identify and review the surgical outcomes of patients who underwent an extended middle fossa rhomboid approach for the resection of hemorrhagic cavernomas involving the lateral pons during a 10-year period at Rady Children’s Hospital of San Diego. Surgical landmarks for this extradural approach were based on the Fukushima dual-fan model, which defines the rhomboid based on the following anatomical structures: 1) the junction of the greater superficial petrosal nerve (GSPN) and mandibular branch of the trigeminal nerve; 2) the lateral edge of the porus trigeminus; 3) the intersection of the petrous ridge and arcuate eminence; and 4) the intersection of the GSPN, geniculate ganglion, and arcuate eminence. The boundaries of maximal bony removal for this approach are the clivus inferiorly below the inferior petrosal sinus; unroofing of the internal auditory canal posteriorly; skeletonizing the geniculate ganglion, GSPN, and internal carotid artery laterally; and drilling under the Gasserian ganglion anteriorly. This extradural petrosectomy allowed for an approach to all lesions from an area posterolateral to the basilar artery near its junction with cranial nerve (CN) VI, superior to the anterior inferior cerebellar artery and lateral to the origin of CN V. Retraction of the mandibular branch of the trigeminal nerve during this approach allowed avoidance of the region involving CN IV and the superior cerebellar artery.RESULTSEight pediatric patients (4 girls and 4 boys, mean age of 13.2 ± 4.6 years) with hemorrhagic cavernomas involving the lateral pons and extension to the pial surface were treated using the surgical approach described above. Seven cavernomas were completely resected. In the eighth patient, a second peripheral lesion was not resected with the primary lesion. One patient had a transient CN VI palsy, and 2 patients had transient trigeminal hypesthesia/dysesthesia. One patient experienced a CSF leak that was successfully treated by oversewing the wound.CONCLUSIONSThe extended middle fossa approach can be used for resection of lateral pontine hemorrhagic cavernomas with minimal morbidity in the pediatric population.

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Middle Fossa Approach for Facial Nerve Schwannoma Aiming for Functional Improvement: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opz178 ◽

2019 ◽

Vol 18 (5) ◽

pp. E167-E168

Author(s):

Ken Matsushima ◽

Michihiro Kohno ◽

Hitoshi Izawa ◽

Yujiro Tanaka

Keyword(s):

Facial Nerve ◽

Facial Palsy ◽

Tumor Resection ◽

Nerve Fibers ◽

Middle Fossa ◽

Tumor Removal ◽

Middle Fossa Approach ◽

Brainstem Response ◽

Facial Nerve Schwannoma

Abstract The treatment paradigm of skull base surgery has been changed from radical tumor resection to maximal tumor removal while giving priority to functional preservation. Facial nerve schwannoma is one of the representative disorders of this type of paradigm shift.1 This video demonstrates facial nerve schwannoma surgery through the middle fossa approach, aiming for improvement of facial function. A 33-yr-old woman presented with gradually worsening facial palsy (House-Brackmann grade IV), dizziness, and nausea. Neuroimaging revealed a growing tumor involving the geniculate ganglion, and extending to the middle fossa, internal acoustic meatus, and cerebellopontine angle. The nerve-sparing surgery through the left middle fossa approach was performed under detailed neuromonitoring including the evoked facial electromyograms and auditory brainstem response. The facial nerve fibers were involved within the tumor mass and the plane between the tumor and facial nerve could not be identified as seen in most cases of such large facial nerve schwannomas. But sufficient tumor removal with facial nerve preservation was achieved owing to continuous facial monitoring.2 The patient had no new neurological deficits. Her facial palsy has been gradually improving, now at grade III, without any signs of tumor regrowth during the 10 mo of follow up after the operation. Careful follow up is being continued to survey the possible tumor recurrence. The video was reproduced after informed consent of the patient.

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Extirpation of Recurrent Petrous Apex Cholesterol Granuloma Through the Zygomatic Approach: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opab156 ◽

2021 ◽

Author(s):

Mark Eisenberg ◽

Walid Ibn Essayed ◽

Ossama Al-Mefty

Keyword(s):

Short Distance ◽

Petrous Apex ◽

Cholesterol Granuloma ◽

Middle Fossa ◽

Resonance Imaging ◽

Endoscopic Endonasal ◽

Middle Fossa Approach ◽

Weighted Magnetic Resonance Imaging ◽

Year 2000 ◽

Air Cells

Abstract Petrous apex cholesterol granulomas are believed to result from blockage of the normal aeration of the petrous air cells, resulting in a repetitive cycle of mucosal engorgement, hemorrhage, and granuloma formation.1 The lesion usually progressively expands causing compressive symptoms. The thick granulomatous wall envelopes various ages of breakdown products, including a cholesterol-containing fluid, which is typically hyperintense on T1 and T2 weighted magnetic resonance imaging. Drainage procedures, regardless of the route (endoscopic, endonasal, or transtemporal), with or without stenting or marsupialization, will only temporarily drain this cholesterol-containing fluid, with consequently frequent recurrences.2-5 A total exoneration of the granuloma and obliteration of the cavity with vascularized tissue will assure a more durable outcome.1 The extradural zygomatic/middle fossa approach provides a short distance to the petrous apex and is purely extradural. By sectioning the zygoma, temporal lobe retraction is avoided.6 We present a case of a 29-yr-old male who presented in the year 2000 with progression of a left petrous apex cholesterol granuloma despite 2 previous drainage and stenting procedures. The patient consented for surgery and photo publication. Images in video at 2:41 © JNSPG, republished from Eisenberg et al1 with permission.

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GREATER SUPERFICIAL PETROSAL NERVE DISSECTION: BACK TO FRONT OR FRONT TO BACK?

Operative Neurosurgery ◽

10.1227/01.neu.0000343522.79764.15 ◽

2009 ◽

Vol 64 (suppl_5) ◽

pp. ons253-ons259 ◽

Cited By ~ 2

Author(s):

Pakrit Jittapiromsak ◽

Hakan Sabuncuoglu ◽

Pushpa Deshmukh ◽

Peter Nakaji ◽

Robert F. Spetzler ◽

...

Keyword(s):

Surgical Technique ◽

Facial Nerve ◽

Proximal Part ◽

Mandibular Nerve ◽

Middle Fossa ◽

Posterior Border ◽

Middle Fossa Approach ◽

Greater Superficial Petrosal Nerve ◽

Retraction Force

Abstract OBJECTIVE To introduce a novel surgical technique for the dissection of the greater superficial petrosal nerve (GSPN) in the middle fossa approach. METHODS Interdural temporal elevation was performed with a front-to-back technique to preserve the GSPN in 12 sides of 6 injected cadaveric heads dissected through a middle fossa approach. RESULTS The GSPN emerged from the facial hiatus in a shallow bony groove proximally, ran into a deeper sphenopetrosal groove, and eventually reached the mandibular nerve. With front-to-back dissection, this nerve was easily identified at the posterior border of the mandibular nerve. Dissection from front to back minimized the retraction force applied to the proximal part of the GSPN, which was preserved in all specimens. CONCLUSION The temporal dura can be elevated safely with a front-to-back technique to preserve the GSPN and to help maintain the physiological integrity of the facial nerve.

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Extended Middle Fossa Approach for Trigeminal Schwannoma Resection

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0041-1727108 ◽

2021 ◽

Author(s):

Baha'eddin A. Muhsen ◽

Edinson Najera ◽

Hamid Borghei-Razavi ◽

Badih Adada

Keyword(s):

Cavernous Sinus ◽

Brain Mri ◽

Clinical Status ◽

Tumor Resection ◽

Cranial Nerves ◽

Petrous Apex ◽

Benign Tumors ◽

Middle Fossa ◽

Middle Fossa Approach ◽

Trigeminal Schwannoma

AbstractTrigeminal schwannomas are rare benign tumors, it is second most common intracranial schwannomas after vestibular schwannomas. The management includes not limited to observation, stereotactic radiosurgery/radiotherapy, and/or surgical resection. Tumor size and patient clinical status are the most important factors in management.In this video, we describe the technical nuances of an extended middle fossa approach for large trigeminal schwannoma with cavernous sinus extension resection. A 44-year-old right-handed female with several months' history of progressive right facial paresthesia and pain in the distribution of V3 mainly. On physical examination, she had decreased sensation to light touch over the right V1 to V3 distribution with loss of cornel reflex. The brain MRI showed 3.5 cm bilobed mass extends from the pontine root entry zone to the cavernous sinus. Craniotomy was performed and followed by middle fossa dural peeling, peeling of temporal lobe dura away from the wall of the cavernous sinus, extradurally anterior clinoidectomy, drilling of the petrous apex, coagulation of superior petrosal sinus followed incision of the tentorium up to the tentorial notch with preservation the fourth cranial nerve, and tumor dissected away from V1 and then gradually removed from the superior wall of the cavernous sinus.The technique presented here allows for complete tumor resection, safe navigation through the relative cavernous sinus compartments, and minimizes the possibility of inadvertent injury to the cranial nerves.The postoperative course was uneventful except for right eye incomplete ptosis from the swelling. Her facial pain subsided after the surgery without any extra ocular movement impairment.The link to the video can be found at: https://youtu.be/zxi2XK2R9QU.

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Endoscope-Assisted Middle Fossa Approach: Optimizing the Surgical Corridor for the Resection of Multicompartmental Chordomas

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0040-1702218 ◽

2020 ◽

Author(s):

André Beer-Furlan ◽

Eduardo de Arnaldo Silva Vellutini ◽

Leonardo Balsalobre ◽

Aldo Cassol Stamm

Keyword(s):

Skull Base ◽

Medical Records ◽

Tumor Resection ◽

Complete Removal ◽

Anatomical Landmarks ◽

Middle Fossa ◽

Middle Fossa Approach ◽

Endoscopic Assistance ◽

Skull Base Chordomas ◽

Surgical Corridor

Abstract Background Skull base chordomas are a major therapeutic challenge. The surgical management involves selecting an approach that will offer the patient the best chance of largest/complete removal while minimizing morbidity and mortality. Methods Medical records and imaging review of two skull base chordomas involving the middle fossa and posterior fossa that were successfully treated with an endoscope-assisted middle fossa approach. Results The use of angled endoscopes provided better identification of anatomical landmarks and improved tumor resection when compared with the microscopic surgical exposure. The approach selection, anatomical landmarks, and technical aspects of the intraoperative setting of the endoscope-assisted approach are discussed. Conclusion Endoscopic assistance in the middle fossa approach is a safe and valuable tool for maximizing the reach of the surgical corridor when treating skull base chordomas.

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Endoscopic Endonasal Transrotundum Middle Fossa Exposure: Technique of Transpterygoid Maxillary Nerve Transposition

World Neurosurgery ◽

10.1016/j.wneu.2018.01.120 ◽

2018 ◽

Vol 112 ◽

pp. 131-137 ◽

Cited By ~ 2

Author(s):

Ricky H. Wong

Keyword(s):

Middle Fossa ◽

Endoscopic Endonasal ◽

Maxillary Nerve ◽

Exposure Technique ◽

Nerve Transposition

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Skull Base Dumbbell Tumor: Surgical Experience with Two Adolescents

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348949210101110 ◽

1992 ◽

Vol 101 (11) ◽

pp. 939-945 ◽

Cited By ~ 8

Author(s):

Roland D. Eavey ◽

Paul H. Chapman ◽

Alfred Weber ◽

Brooke Swearingen ◽

Kenneth R. Davis ◽

...

Keyword(s):

Skull Base ◽

Infratemporal Fossa ◽

Tumor Resection ◽

Middle Cranial Fossa ◽

Postoperative Recovery ◽

Artery Occlusion ◽

Spindle Cell Sarcoma ◽

Middle Fossa ◽

Dumbbell Tumor ◽

Middle Fossa Approach

Pediatric skull base tumors are rare and until recently were considered unresectable. We present two patients with tumors of similar anatomic position with an extracranial component in the infratemporal fossa and parapharyngeal space, an isthmus at the foramen ovale, and a superior component in the middle cranial fossa in the region of the cavernous sinus. A 15-year-old girl experienced contiguous spread of a spindle cell sarcoma; an 18-year-old boy developed a chondrosarcoma. A middle fossa approach provided the advantage of surgical avoidance of structures such as the middle ear and mastoid, facial nerve, and mandible. Postoperative recovery was rapid. Our impression is that preoperative carotid artery occlusion and a middle fossa approach for tumor resection can be performed in a young patient with acceptable morbidity and at least short-term benefit. Surgery can, therefore, provide an additional therapeutic approach to complement irradiation and chemotherapy.

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