A lateral transzygomatic-transtemporal approach to the infratemporal fossa: technical note for mobilization of the second and third branches of the trigeminal nerve

Preauricular retromandibular trans tympanic plate and styloid process keyhole approach to parapharyngeal lesions: a laboratory study

BACKGROUND

The surgical removal of the infratemporal parapharyngeal lesions (IPL) is challenging due to its anatomical complexity. Previous surgical approaches have often been too invasive and necessitated sacrifice of normal function and anatomical structures, particularly in the retromandibular nerve region. Therefore, we sought to identify an approach corridor to this area that requires less sacrifice and report an innovative approach through a retromandibular fossa route to the IPL.

METHODS

Five cadaveric specimens were dissected bilaterally with a trans-tympanic plate and styloid process approach. These specimens were investigated microanatomically and morphometrically to examine the extent of the approach in the parapharyngeal space. The clinical application of this approach was compared to previous approaches to the IPL used in our clinical series of 20 cases.

RESULTS

Using this novel approach, the inferior alveolar nerve was identified in all specimens, while the chorda tympani and lingual nerve were identified in 6 (60%) and 4 (40%) dissections, respectively. In all specimens, the petrous portion of the internal carotid artery and the exit of the lower cranial nerve were identified. The average length of the exposed lower cranial nerves was 16.6 ± 3.8 mm (range: 11-25 mm).

CONCLUSIONS

The described approach is feasible for accessing the IPL at the retromandibular nerve and is less invasive than conventionally used approaches.

Role of transcranial sphenoidotomy in skull base surgery: classification of surgical techniques based on the surgical anatomy of the sphenoid sinus

OBJECTIVE

Although sphenoidotomy is more commonly performed via the transnasal approach than via the transcranial approach, transcranial sphenoidotomy (TCS) remains indispensable for en bloc resection of locally advanced sinonasal malignant tumors (SNMTs) extending to the skull base. TCS also enables transsphenoidal transposition of the temporoparietal galeal flap (TPGF) to compensate for the lack of vascularized reconstructive tissue after endoscopic transnasal skull base surgery. The objective of this study was to review the authors' surgical experience using TCS with an emphasis on the surgical anatomy of the sphenoid sinus and on the purpose of TCS. Relevant anatomy is further illustrated through cadaveric dissection and photo documentation.

METHODS

The authors reviewed the records of 50 patients who underwent TCS at the Nagoya University Hospital, Fukushima Medical University Hospital, or Aichi Medical University Hospital over the course of 7 years (between January 2011 and November 2017). The authors also performed cadaveric dissection in 2 adult cadaveric skull base specimens.

RESULTS

Of the 50 patients included in this study, 44 underwent craniofacial resection (CFR) for en bloc resection of SNMTs involving the anterior and/or lateral skull base, and 6 underwent transsphenoidal transposition of the TPGF flap. The authors categorized the TCS procedures according to the portion of the sphenoid sinus wall involved (i.e., superior, lateral, and superolateral). Superior sphenoidotomy was used in patients requiring anterior CFR. Lateral sphenoidotomy was further divided into 2 subtypes, with type 1 procedures performed for the transsphenoidal transpositioning of the TPGF, and type 2 procedures used in patients requiring lateral CFR. Superolateral sphenoidotomy was used in anterolateral CFR.

CONCLUSIONS

TCS still represents a useful tool in the armamentarium of neurosurgeons treating central skull base lesions. The newly proposed surgical classification facilitates a profound understanding of TCS and how to incorporate this technique into clinical practice.

Trigeminal neurofibroma in the infratemporal fossa arising from the inferior alveolar nerve: A case report

Solitary neurofibromas arising from cranial nerves are rare, and those arising from the peripheral divisions of the trigeminal nerve are even rarer. Although infratemporal fossa (ITF) masses are challenging to remove, certain approaches are considered feasible for this region. The present study reports a rare case of an ITF neurofibroma arising from the inferior alveolar nerve. The 27-year-old male patient presented with numbness of the right jaw. A radiological examination revealed a large mass occupying the ITF, from the mandible to the foramen ovale, originating from the inferior alveolar nerve in the mandible. The tumor was successfully excised via a transtemporal approach followed by a transoral-retromolar approach. A histological examination confirmed the diagnosis of neurofibroma. The present case demonstrates that a combination of the transtemporal and transoral-retromolar approaches may provide wide access to the ITF region.

Transzygomatic Approach to Skull Base: History, Evolution, and Possibility of a Simple Modification

The surgical approaches to anterior, middle, and lateral skull base have evolved drastically, transcending from an era of oblivion to well-defined and systematically executed, state-of-the-art, refined surgery. The transzygomatic approach, which was developed to access the nasopharynx, has been applied to versatile locations of skull base pathology, with continuous evolution and modification of the osteotomies and skin flaps involved. A simple modification is proposed which could help reach a compromise between the wide exposure provided by the hemicoronal incision and the minimally invasive preauricular approach.

Combined Transzygomatic and Pterional Approach for Resection of a Dermoid Cyst of the Foreman Ovale

Dermoid cysts are rare, benign intracranial lesions commonly located in the posterior fossa. We describe a uniquely located dermoid cyst in the foreman ovale resected via a combined pterional and transzygomatic approach.

Middle infratemporal fossa less invasive approach for radical resection of parapharyngeal tumors: surgical microanatomy and clinical application

Surgery of the infratemporal fossa (ITF) and parapharyngeal area presents a formidable challenge to the surgeon due to its anatomical complexity and limited access. Conventional surgical approaches to these regions were often too invasive and necessitate sacrifice of normal function and anatomy. To describe a less invasive transcranial extradural approach to ITF parapharyngeal lesions and to determine its advantages, 17 patients with ITF parapharyngeal neoplasms who underwent tumor resection via this approach were enrolled in the study. All lesions located in the ITF precarotid parapharyngeal space were resected through a small operative corridor between the trigeminal nerve third branch (V3) and the temporomandibular joint (TMJ). Surgical outcomes and postoperative complications were evaluated. Pathological diagnosis included schwannoma in eight cases, paraganglioma in two cases, gangliocytoma in two cases, carcinosarcoma in one case, giant cell tumor in one case, pleomorphic adenoma in one case, chondroblastoma in one case, and juvenile angiofibroma in one case. Gross total resection was achieved in 12 cases, near-total and subtotal resection were in 3 and 2 cases, respectively. The most common postoperative complication was dysphagia. Surgical exposure can be customized from minimal (drilling of retrotrigeminal area) to maximal (full skeletonization of V3, removal of all structures lying lateral to the petrous segment of internal carotid artery) according to tumor size and location. Since the space between the V3 and TMJ is the main corridor of this approach, the key maneuver is the anterior translocation of V3 to obtain an acceptable surgical field.

Transzygomatic approach with intraoperative neuromonitoring for resection of middle cranial fossa tumors

The authors reviewed the surgical experience and operative technique in a series of 11 patients with middle fossa tumors who underwent surgery using the transzygomatic approach and intraoperative neuromonitoring (IOM) at a single institution. This approach was applied to trigeminal schwannomas (n = 3), cavernous angiomas (n = 3), sphenoid wing meningiomas (n = 3), a petroclival meningioma (n = 1), and a hemangiopericytoma (n = 1). An osteotomy of the zygoma, a low-positioned frontotemporal craniotomy, removal of the remaining squamous temporal bone, and extradural drilling of the sphenoid wing made a flat trajectory to the skull base. Total resection was achieved in 9 of 11 patients. Significant motor pathway damage can be avoided using a change in motor-evoked potentials as an early warning sign. Four patients experienced cranial nerve palsies postoperatively, even though free-running electromyography of cranial nerves showed normal responses during the surgical procedure. A simple transzygomatic approach provides a wide surgical corridor for accessing the cavernous sinus, petrous apex, and subtemporal regions. Knowledge of the middle fossa structures is essential for anatomic orientation and avoiding injuries to neurovascular structures, although a neuronavigation system and IOM helps orient neurosurgeons.

Late diagnosis of a solitary fibrous tumour of the parapharyngeal space in a continuous positive airway pressure-treated patient

Solitary fibrous tumours of the parapharyngeal space are a very rare finding and have been described less than 10 times in the English literature. The Authors discuss a clinical case of a solitary fibrous tumour in the parapharyngeal space in a 77-year-old male, who had begun treatment for a newly discovered obstructive sleep apnoea syndrome with a continuous positive airway pressure - device one year prior to diagnosis. This rare location of an uncommon lesion often gives rise to difficulty in diagnosis or to misdiagnosis and the Authors, therefore, made a review of the scientific literature and analysed the diagnostic and therapeutic procedures used. The importance of this report lies mainly in two aspects: on the one hand, the discussion concerning the diagnostic and therapeutic procedures and on the other, the need of a thorough evaluation in obstructive sleep apnoea syndrome patients before treating them with a chronic device like the continuous positive airway pressure device.

The maxillary artery and the lateral pterygoid muscle: the New Zealand story

OBJECTIVE

The most recent study of the relationship between the maxillary artery and the lateral pterygoid muscle was published in this journal in 2008.(1) Given the controversy surrounding this relationship, our purpose was to present data gathered from New Zealand caucasoid cadavers over several years.

STUDY DESIGN

Both sides of 92 caucasoid adult cadaveric heads (45 male, 47 female) were dissected by 3 successive years of third-year medical students and second-year dental students. The infratemporal approach was used. Once the dissections reached the plane of the maxillary artery and lateral pterygoid muscle, their relationship was recorded, together with exemplary images. Sexual and symmetrical differences were noted.

RESULTS

In the 53 cases where bilateral dissection had been successful, the second part of the maxillary artery was found superficial to the lower head of the lateral pterygoid muscle in 30 cases (57%)-in 70% of the males and 39% of the females. One male and 1 female presented bilateral asymmetry.

CONCLUSIONS

The finding of 2 cases of bilateral asymmetry among the 53 bilaterally dissected cadavers led to the consideration of each "hemi-head" as a single entity. This increased the sample size. Statistical analysis of the data, systematically broken down by sex and by side, showed that the second part of the maxillary artery is more likely to lie deep to the lower head of the lateral pterygoid muscle in females than in males, and that "side" is irrelevant.

Trans-zygomatic middle cranial fossa approach to access lesions around the cavernous sinus and anterior parahippocampus: a minimally invasive skull base approach

PURPOSE

Exposure of the cavernous sinus or anterior parahippocampus often involves a wide exposure of the temporal lobe and mobilization of the temporalis muscle associated with temporal lobe retraction. The authors present a cadaveric study to illustrate the feasibility, advantages and landmarks necessary to perform a trans-zygomatic middle fossa approach to lesions around the cavernous sinus and anterior parahippocampus.

METHODS

The authors performed bilateral trans-zygomatic middle fossae exposures to reach the cavernous sinus and parahippocampus in five cadavers (10 sides). We assessed the morbidity associated with this procedure and compared the indications, advantages, and disadvantages of this method versus more extensive skull base approaches. A vertical linear incision along the middle portion of the zygomatic arch was extended one finger breadth inferior to the inferior edge of the zygomatic arch. Careful dissection inferior to the arch allowed preservation of facial nerve branches. A zygomatic osteotomy was followed via a linear incision through the temporalis muscle and exposure of the middle cranial fossa floor.

RESULTS

A craniotomy along the inferolateral temporal bone and middle fossa floor allowed extradural dissection along the middle fossa floor and exposure of the cavernous sinus including all three divisions of the trigeminal nerve. Intradural inspection demonstrated adequate exposure of the parahippocampus. Exposure of the latter required minimal or no retraction of the temporal lobe.

CONCLUSIONS

The trans-zygomatic middle fossa approach is a simplified skull base exposure using a linear incision, which may avoid the invasivity of more extensive skull base approaches while providing an adequate corridor for resection of cavernous sinus and parahippocampus lesions. The advantages of this approach include its efficiency, ease, minimalism, preservation of the temporalis muscle, and minimal retraction of the temporal lobe.

[The infratemporal fossa oncological surgery]

INTRODUCTION

The infratemopral fossa pathology cases are very rare. They grow unnoticed for considerable period until there are some impairments of function of the anatomical structures of the place. Aim. The aim of the paper was to recollect the information about rare cases the pathological state of the area in common laryngological practice. MATERIAL AND MEHOD: The study was carried out on three cases with tumors localizated in the infratemporal fossa, treated in Department of Otolaryngology of Military Clinical Hospital in Krakow (Poland) in the period from 2006 to 2008. The surgical treatment was preceded by precise picture diagnostic. The transzygomatiz approach were used in two cases. The buccal approach to maxilla in one case. Furthermore, in the last case the tumor expanded to parapharyngeal space which was explorated by parotido-cervical approach. The delayed post operative follow-up were carried out.

Parapharyngeal branchial cleft cyst extending to the skull base: a lateral transzygomatic-transtemporal approach to the parapharyngeal space

Second branchial cleft cysts (BCCs) can occur anywhere from the tonsillar fossa to the supraclavicular area. Second BCCs usually lie on the great vessels of the neck, deep in the sternocleoidomastoid muscle or along its anterior border at the mandibular angle. Parapharyngeal second BCCs are an uncommon neoplasm and rarely extend to the skull base. We report the case of a 45-year-old male with symptoms of conductive hearing loss. Temporal bone CT scan showed effusion in the left middle ear cavity. Magnetic resonance imaging (MRI) revealed a cystic mass that was located at the left parapharyngeal space and eroded the skull table of the left temporal base. Excision of the lesion was achieved via a transzygomatic-transtemporal approach to the parapharyngeal space. Histopathological examination of the cyst wall showed a single layer of ciliated columnar epithelium without goblet cells or lymphoid tissue. The patient recovered without any complications and experienced complete resolution of left-sided hearing difficulty. We conclude the lateral transzygomatic-transtemporal approach allows surgeons direct access to the parapharyngeal space with satisfactory exposure for treating benign lesions of the parapharyngeal space.