Giant Pleomorphic Adenoma of Infratemporal Fossa: A Rare Case Report.

Of all the head and neck tumors, salivary gland tumors account to 3%. Pleomorphic adenomas are one of the most common benign tumors arising from major salivary glands, although it could also develop from minor salivary glands situated at accessory sites like nasal cavity, pharynx, parapharyngeal space, lacrimal glands etc. Tumors of infratemporal fossa are quite unusual, mainly because of its hidden location in retromaxillary region. We report an unusual case of 65 years old male presenting with complaint of progressive left cheek swelling for 4 years. FNAC revealed pleomorphic adenoma of minor salivary gland tumor. Intraoperatively a giant lobulated tumor was seen occupying almost whole space of infratemporal fossa, which was removed in-toto via open approach. Patient was kept on regular follow up with no evidence of recurrence reported till date.

Anterior endoscopic sublabial transmaxillary access to middle cranial base lesions.

BACKGROUND: Anterior endoscopic access to middle cranial base lesions becomes feasible in the presence of infratemporal fossa (ITF) involvement. Various approaches, including endoscopic endonasal, transoral sublabial, and transorbital methods, have been described for accessing the ITF through a transmaxillary corridor. Among these approaches, endonasal access is the most commonly preferred, while the transorbital approach is a novel technique gaining popularity. The transoral sublabial approach is considered suitable for selected lesions. METHODS: Patients who underwent the anterior endoscopic transoral/sublabial transmaxillary approach to middle cranial base lesions at a single institute from 2016 to 2023 were included in this retrospective study. Malignant lesions were excluded from the study. The sublabial approach was exclusively performed in all cases, with the exception of one patient who required a combined approach. RESULTS: The anterior endoscopic transoral sublabial transmaxillary approach to the infratemporal fossa, upper parapharyngeal space, and middle cranial fossa was performed on 14 patients. The underlying conditions for these patients were as follows: trigeminal schwannomas (n = 8), meningiomas (n = 2), juvenile nasopharyngeal angiofibroma, osteochondroma, arachnoid cyst and encephalocele (n = 1 each). Gross total resection was achieved in 11 cases. The most common complication was numbness in the territory of the maxillary and mandibular nerves (n = 4). Two patients needed endoscopic maxillary antrostomy for persistent suppuration. No wound problems or CSF rhinorrhea occurred. The average follow-up time was 26.6 months. CONCLUSION: The endoscopic sublabial transmaxillary approach provides direct access to the infratemporal fossa and middle cranial base, enhancing the surgical range of maneuverability while sparing the sinonasal cavity. This procedure is safe, less invasive, and could be used as an efficient corridor for the resection of selected infratemporal fossa lesions with or without extension to the middle cranial base and parapharyngeal space.

Localization of Maxillary Artery for Cerebral Revascularization: L-Shaped Perpendicular Two-Step Drilling Technique Stretching from the Foramen Ovale to Rotundum.

BACKGROUND: The use of the maxillary artery (MA) as a donor has increasingly become an alternative method for cerebral revascularization. Localization difficulties emerge due to rich infratemporal anatomical variations and the complicated relationships of the MA with neuromuscular structures. We propose an alternative localization method via the interforaminal route along the middle fossa floor. METHODS: Five silicone-injected adult cadaver heads (10 sides) were dissected. Safe and effective localization of the MA was evaluated. RESULTS: The MA displayed anatomical variations in relation to the lateral pterygoid muscle (LPM) and the mandibular nerve branches. The proposed L-shaped perpendicular 2-step drilling technique revealed a long MA segment that allowed generous rotation to the intracranial area for an end-to-end anastomosis. The first step of drilling involved medial-to-lateral expansion of foramen ovale up to the lateral border of the superior head of the LPM. The second step of drilling extended at an angle approximately 90° to the initial path and reached anteriorly to the foramen rotundum. The MA was localized by gently retracting the upper head of the LPM medially in a posterior-to-anterior direction. CONCLUSIONS: Considering all anatomical variations, the L-shaped perpendicular 2-step drilling technique through the interforaminal space is an attainable method to release an adequate length of MA. The advantages of this technique include the early identification of precise landmarks for the areas to be drilled, preserving all mandibular nerve branches, the deep temporal arteries, and maintaining the continuity of the LPM.

Endoscopic trans-eustachian tube approach: identifying the precise landmarks, a novel radiological and anatomical evaluation.

PURPOSE: The endoscopic trans-eustachian approach (ETETA) is a less invasive approach to the infratemporal fossa (ITF), providing superior exposure compared to traditional transcranial approaches. The anatomy of the pharyngotympanic (eustachian) tube and adjacent neurovascular structures is complex and requires in-depth knowledge to safely perform this approach. We present a cadaveric and radiological assessment of critical anatomic considerations for ETETA. METHODS: Six adult cadaveric heads were dissected alongside examination of 50 paranasal sinus CT scans. Key anatomic relationships of the pharyngotympanic tube and adjacent structures were qualitatively and quantitatively evaluated. Descriptive statistics were performed for quantitative data. RESULTS: Anatomical and radiological measurements showed lateralization of the pharyngotympanic tube allows access to the ITF. The pharyngotympanic tube has bony and cartilaginous parts with the junction formed by the sphenoid spine and foramen spinosum. The bony part and tendon of the tensor tympani muscle were located at the posterior genu of the internal carotid artery. The anterior and inferior wall of the carotid canal was located between the horizontal segment of the internal carotid artery and petrous segment of the cartilaginous pharyngotympanic tube. CONCLUSION: The combination of preoperative radiographic assessment and anatomical correlation demonstrates a safe and effective approach to ETETA, which allowed satisfactory visualization of ITF. The morphological evaluation showed that the lateralization of the pharyngotympanic tube and related structures allowed a surgical corridor to reach the ITF. Endoscopic surgery through the pharyngotympanic tube is challenging, and in-depth understanding of the key anatomic relationships is critical for performing this approach.

Respiratory Epithelial Adenomatoid Hamartoma at an Unusual Location: A Case Report and Literature Review.

Respiratory epithelial adenomatoid hamartoma (REAH) in the head and neck is a rare benign lesion containing glandular tissue covered with ciliated respiratory epithelium. In the head and neck, REAH of the nasal cavity, paranasal sinuses, and nasopharynx have been reported in literature. Due to rareness of REAH and insufficient knowledge of its imaging features, the diagnosis can be challenging when we encounter a non-specific cystic mass at an uncommon site in the head or neck. Here, we report the case of a pathologically confirmed REAH showing a cystic mass centered at the buccal space (retromaxillary fat pad) with CT and MRI findings.

Malignant myoepithelioma of the external auditory canal - a rare case report with literature review and clinical importance of foramen of Huschke.

BACKGROUND: A malignant myoepithelioma is a rare tumor, mostly arising from the salivary glands. Myoepitheliomas of the ear have rarely been reported. The manuscript reports myoepithelial carcinoma of the external auditory canal (EAC) spreading to the infratemporal fossa. A clinician must be aware of anatomical variation of the bony EAC wall, such as the foramen of Huschke. This rare defect may be a pathway for spreading pathologies between these two anatomical regions. CASE REPORT: We present a case of osteoma-like stenosis of the EAC, which turned out to be an extremely rare malignant tumor. The preoperative MRI and PET/CT revealed that two parts of the tumor communicated through a defect in the antero-inferior portion of the bony ear canal. No distant metastases were detected. Subsequently, the tumor was resected from the ear canal and the infratemporal fossa en bloc. Perioperatively the defect in the EAC wall was suspected of the foramen of Huschke. After the surgery, the older scans of the patient from the past showed no presence of a congenital EAC wall defect. Therefore, the authors concluded that the tumor aggressively grew through the bone due to its biological nature. CONCLUSION: Malignant myoepithelioma of the external auditory canal is an extremely rare condition and could be misdiagnosed as other benign lesions. In cases of suspicious lesions, it is advisable to do a probatory biopsy from the EAC. Surgery is the treatment of choice in malignant myoepitheliomas, and regular follow-ups are essential to monitor for recurrence or metastatic disease. Any mass located at the antero-inferior portion of the EAC wall warrants close evaluation due to its potential for expansion from the EAC.

Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Endoscopic Endonasal and Endoscopic-Assisted Transmaxillary Transpterygoid Approaches.

Introduction The endoscopic endonasal transpterygoid approach (EETPA) with or without the addition of the endoscopic-assisted sublabial anterior transmaxillary approach (ESTA) has become increasingly utilized for lesions posterior to the pterygopalatine fossa (PPF), including infratemporal fossa (ITF), lateral recess of the sphenoid sinus, Meckel's cave, petrous apex, and parapharyngeal space. The main goal of this study is to develop an educational resource to learn the steps of the EETPA for trainees. Methods EETPA and ESTA were performed in 12 specimens by neurosurgery trainees, under supervision from the senior authors. One EETPA and one ESTA were performed on each specimen on opposite sides. Dissections were supplemented with representative cases. Results After a wide unilateral sphenoidotomy, ethmoidectomy, and partial medial maxillectomy, the anteromedial bone limits of the PPF were identified and drilled out. The pterygoid progress was modularly removed. By enlarging the opening of the posterior and lateral walls of the maxillary sinus through EETPA and ESTA, respectively, the neurovascular and muscular compartments of the PPF and ITF were better identified. The EETPA opens direct corridors to the PPF, medial ITF, middle cranial fossa, cavernous sinus, Meckel's cave, petrous apex, and internal carotid artery. If a more lateral exposure of the ITF is needed, the ESTA is an appropriate addition. Conclusion Despite the steep learning curve of the EETPA, granular knowledge of its surgical anatomy and basic surgical steps are vital for those advancing their learning in complex endoscopic approaches to the ventral skull base when expanding the approach laterally in the coronal plane.

Infratemporal Fossa Metastasis of Non-Small-Cell Lung Adenocarcinoma: A Case Report and Literature Review.

Neoplasms in the infratemporal fossa (ITF) are rare and insidious lesions that cause various symptoms due to involvement of the temporomandibular joint (TMJ), paranasal sinuses, and orbit. Here, we report a case of metastatic non-small cell lung adenocarcinoma in the ITF. The patient presented with facial pain and limited mouth opening, which did not respond to treatment for TMJ disorder, and a neoplasm was discovered in the ITF through medical imaging. With an open biopsy, the diagnosis was finalized. This report suggested that the physician should consider lesions in the ITF when facial pain and limited mouth opening failed local treatment, and distant metastasis of malignant tumor should be alerted. We also reviewed the literature regarding metastatic cancer to the ITF.

Musculus pterygoideus proprius: A meta-analysis.

The pterygoideus proprius muscle can be found incidentally in the infratemporal fossa, where it is spatially associated with the muscles of mastication, the maxillary artery, and the trigeminal nerve and its branches. Anatomists have described the muscle in various ways over the past 160 years, chiefly as a musculotendinous structure that originates from the infratemporal crest of the sphenoid bone and inserts into the lateral pterygoid plate and the lateral pterygoid muscle. It is present in non-human primates, albeit rarely, with similar anatomical findings. Embryologically, the pterygoideus proprius is thought to have developed from the first pharyngeal arch mesenchyme along with other muscles of mastication. Its close association with the maxillary artery and trigeminal nerve suggests possible clinical significance in trigeminal neuralgia and temporomandibular joint disorders. The literature was reviewed systematically to detail the historical background of research on the pterygoideus proprius muscle and explain its morphology, prevalence, embryology, and potential clinical significance. Despite its rarity, we propose that it is important to recognize its presence when the infratemporal fossa is approached.

Pterygopalatine-Infratemporal Fossa Hydatid Cyst Resembling Cystic Tumor.

Hydatid cyst is an endemic disease in Mediterranean and Middle Eastern countries, Eastern European countries, East Africa, China, New Zealand, Australia. We aimed to present this educational case, which is endemic in our country and seen in a very rare localization, with the combined surgical approach, within the literature.

An endoscopic transnasal prelacrimal recess transmaxillary approach to the pterygopalatine fossa and infratemporal fossa.

Objective: In this paper, the goal of the authors is to present the anatomic nuances and their clinical experience with lesions of the pterygopalatine fossa and infratemporal fossa using an endoscopic transnasal prelacrimal recess transmaxillary approach (PLRMA). Methods: An endoscopic anatomical dissection of three fresh cadaveric heads was performed bilaterally to evaluate the feasibility of the PLRMA. Prior to dissection, stereotactic computed tomography scans were obtained for each head to obtain anatomical measurements. The area of exposure on the posterior wall of the maxillary sinus was determined using stereotaxis. The cases of six patients with schwannomas or epidermoid cysts who underwent the transnasal PLRMA were illustrated. Results: The mean area of exposure on the posterior wall of the maxillary sinus was 9.55 cm2. Total resection was achieved in all six patients. The mean follow-up time was 16 months, and one patient complained of postoperative facial numbness, which resolved gradually. No cases of chronic sinusitis were reported. Conclusions: The endoscopic transnasal PLRMA provides efficient operative exposure to the pterygopalatine fossa and infratemporal fossa. Preserving the integrity of the mucosa on the nasal lateral wall is an advantage of this approach.

A Meta-analysis of Surgical Outcomes of T4a and Infranotch T4b Oral Cancers.

OBJECTIVE: To determine the overall surgical outcomes of infranotch T4b oral cancers and compare them with T4a oral cancers. METHODS: PubMed, EMBASE and Cochrane databases from 2000 to 2022 were systematically searched. Clinical studies reporting at least one outcome following curative surgery and adjuvant therapy for comparison of patients with either infranotch T4b (IN-T4b) or T4a tumour. The heterogeneity of the included studies was determined using Tau-squared, Chi-squared, and the Higgins I2 test. The random effects model was used to determine the log odds ratio (logOR). RESULTS: The systematic review comprised 11,790 patients from 16 included studies. Seven studies were included in the meta-analysis (n = 11,381). For IN-T4b patients, the pooled 2 and 5 year overall survival (OS) were 59.3% and 53.2%, 2 and 5 year disease-free survival (DFS) 57.9% and 48.4%, 2 and 5 year disease-specific survival (DSS) 72% and 68%, and 2 and 5 year local control (LC), 47% and 56%, respectively. There was no statistically significant difference in 2 year OS [logOR = 0.28 (-0.47, 1.03), p = 0.46, confidence interval (CI) = 95%], 5 year OS [logOR = 0.7 (-0.4, 1.8), p = 0.54, CI = 95%], 2 year DFS [logOR = 0.22 (-0.35, 0.79), p = 0.45, CI = 95%], 5 year DFS [logOR = 0.17 (-0.42, 0.77), p = 0.57, CI = 95%], 2 year LC [logOR = 0.47 (-0.33, 1.26), p = 0.25, CI = 95%] and 5 year LC [logOR = 0.34 (-0.31, 0.99), p = 0.31, CI = 95%] between IN-T4b and T4a oral cancers. CONCLUSION: Results of this meta-analysis suggest that IN-T4b oral cancers have similar outcomes to T4a oral cancers, which supports down-staging IN-T4b cancers to T4a cancers.

Infratemporal Fossa Abscess Drainage via a Trans-Oral Image Guided Approach.

Deep neck space infections can cause antibiotic-resistant abscesses that can impinge on vital anatomical structures. Image-guided surgery systems using preoperative computed tomography (CT) imaging can be utilized to characterize pathology and assist surgeons in avoiding iatrogenic injury. This manuscript explores the presentation and unique CT-guided surgical management of an infratemporal fossa abscess in a 48-year-old male who presented with left-sided dental pain and facial swelling that had progressed despite antibiotics and dental extraction. CT-guided imaging can assist in localizing and protecting vital anatomical structures during deep neck abscess drainage and can prevent the potential risks and complications of classic surgical approaches.

Quality of Life in Patients With Benign Lateral Skull Base Neoplasms Following Infratemporal Fossa Approaches.

Objectives: Infratemporal fossa approaches (IFAs) allow the total resection of certain lateral skull base neoplasms. To date, no studies have explored the change of patient-reported quality of life (QoL) after total resection of benign lateral skull base neoplasms through IFA. The present study aimed to give a comprehensive understanding of QoL among patients after IFA through general and disease-specific QoL questionnaires. Methods: Forty-seven patients with benign lateral skull base neoplasms were enrolled. The Short Form 36 (SF-36), World Health Organization Quality of Life-BREF (WHOQOL-BREF), and the University of Washington Head and Neck Quality of Life (UW-QOL) were chosen as tools to assess QoL before and after surgeries through IFA. Results: Patients had significantly lower scores in appearance, chewing, and speech after surgeries through IFA. However, change in health from SF-36 and physical health from WHOQOL-BREF scored higher after surgery. In multivariate linear regression analysis, age, gender, mood, speech, appearance, swallowing, and chewing contributed independently to general QoL. Conclusion: Patients were shown to benefit with regard to overall QoL after gross tumor resection from IFA, despite the impact of appearance, speech, and chewing. Function preservation and restoration are critical since their correlation with postoperative QoL.

Dermoid cyst of the infratemporal fossa: a case report of surgical resection by infratemporal fossa type B approach.

OBJECTIVE: This is a case report of a dermoid cyst located in the infratemporal fossa and its surgical removal using infratemporal fossa type B approach. CASE REPORT: A 15-year-old male was referred from a local clinic after an incidental finding of a mass lesion in the skull base area on computed tomography (CT). Pre-operative magnetic resonance imaging showed a large cystic mass lesion, expanding to the foramen ovale with fat component in the right infratemporal fossa region. The lesion was completely excised using an infratemporal fossa type B approach. CONCLUSION: An extremely rare case of dermoid cysts of the infratemporal fossa was managed with infratemporal fossa type B approach without severe complication.

Trigeminal Schwannoma - Case Report of a Rare Tumour.

Schwannomas are benign nerve tumours arising from the Schwann cells. Approximately 25-45% of schwannomas occurs in the head and neck region. Majority of schwannomas in the head and neck region arise from the vagus nerve. Trigeminal schwannomas account for about 0.2% of all intracranial tumours. Trigeminal schwannomas can originate from any section of the fifth cranial nerve, from the root to the distal extracranial branches, but majority develops from the Gasserian ganglion, usually growing in the middle cranium. Most common presenting symptom is facial pain. MRI is the imaging modality of choice and CT scan usually serves as a supplementary imaging especially for skull base tumours. 47 year old male patient presented to the outpatient department with complains of swelling over the left side of palate. Contrast enhanced CT scan demonstrated a large bilobed heterogeneously enhancing soft tissue lesion in the left infratemporal fossa with widened foramen ovale and extension of lesion into the Meckel's cave, larger contiguous component extending into ramus of mandible. MRI scan showed a large lobulated mass in the left masticator space with intracranial extension. Biopsy of the lesion was suggestive of schwannoma. The patient underwent left composite resection with dural repair and free flap reconstruction. Post operatively, on day 5 he developed features of meningitis for which he was treated conservatively and later discharged in stable condition. Trigeminal schwannomas are rare tumours with very low chance of malignant transformation which commonly presents with facial pain. MRI is the imaging modality of choice. Complete surgical excision is the treatment of choice.

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.

Transoral Marsupialization of an Isolated Surgical Ciliated Cyst of the Infratemporal Fossa.

Surgical ciliated cysts occur primarily in the maxilla after radical maxillary sinus surgery. We report the first case of a surgical ciliated cyst that developed in the infratemporal fossa 25 years after the patient sustained severe facial trauma. The patient complained of mandibular pain and limited mouth opening. The patient's condition was completely resolved 5 months after marsupialization via Le Fort I osteotomy. Surgical morbidities can be minimized by proper diagnosis and less invasive surgery.

Sinonasal and Infratemporal Schwannoma: Rare Case Report with Literature Review.

Schwann cells are responsible for the production of the myelin sheath around the axons of the peripheral nervous system. Benign neoplasms which originate from Schwann cells are hence termed Schwannomas or Neurilemmomas. They present as slow-growing, solitary, encapsulated, benign masses usually in association with nerve trunks. Schwannomas are relatively rare tumors with 25-45% occurring in the head and neck region. These case reports aim to describe the presentations, work-up, and treatment of two patients with head and neck schwannoma in atypical locations. Both patients had a history of gradually increasing swelling, the first originating from the sino-nasal region and the second from the temporal/ infratemporal region. Complete surgical excision of the tumor was done in both cases with no reported recurrence at 18 months follow-up. The final diagnosis was made based on histopathology and immunohistochemistry findings. Schwannomas often present a diagnostic dilemma and should be considered a possibility in all head and neck tumors. Recurrence is rare.

Enbloc resection of primary oral cancer involving infratemporal fossa: A systematic "out to in and top to bottom" surgical approach and outcomes.

AIM AND INTRODUCTION: The oral cavity Squamous Cell Carcinoma (OCSCC) involving infratemporal fossa (ITF) is considered as cT4b stage per AJCC 8th classification. The treatment of these group of patients is challenging due to the difficulty in achieving negative resection margin status. In this study we have highlighted our surgical technique with oncological outcome of enbloc resection of primary oral cancer involving ITF. METHODOLOGY: - This was a single center retrospective study which included only patients with OCSCC extending into ITF. Our surgical technique of systematic "out to in and top to bottom" approach was detailed. The perioperative outcomes, histopathological details, survival outcomes were measured. RESULTS: - Over the period of 1 year a total of 340 patients with OCSCC reported to our outpatient department, out of which 120 patients belonged to cT4 category and 32 patients were cT4b stage with involvement of ITF. Amongst 32 patients, 2 patients had distant metastasis and were excluded from the study. The 5 patients received neoadjuvant chemotherapy followed by surgery and rest all patients were taken up for upfront curative surgery. There were no significant intraoperative and postoperative complications. None of the margins were found to be involved or close in the final histopathology report. The median DFS and OS were 31 months and 27 months respectively at a median follow up of 29 months. CONCLUSION: - Our systematic approach of enbloc resection of primary oral cancer involving ITF is safe and easily reproducible with high rate of negative resection margin status.