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A 42-year-old male presented to the Department of Oral and Maxillofacial Surgery with the chief complaint of pain and stiffness in the right temporomandibular joint (TMJ). The patient's height was 174 cm and his body weight was 65 kg. The patient's occupation was heavy equipment operator. According to the patient, the pain had initiated a week prior to his first visit and was exacerbated during mastication. Evaluation of the range of motion revealed extensive crepitus along the right TMJ. The active and passive range of motion were measured at 45 mm and 42 mm, respectively, indicating adequate mouth-opening capacity. Occlusion was also favorable, and no other clinical symptoms were shown intraorally. [ABSTRACT FROM AUTHOR]

Objective Spontaneous temporal encephaloceles (STEs) are increasingly recognized as sequelae of idiopathic intracranial hypertension (IIH), which in turn may further complicate their management. We endeavored to review the University of Pennsylvania institutional experience on operative management of STEs, with a focus on factors which may influence surgical outcomes, particularly IIH. Design Retrospective chart review over 9 years from 2013 to 2022. Setting Single-center, two-hospital, tertiary care, academic setting. Participants Patients undergoing middle cranial fossa (43.9%), transmastoid (44.9%), or combined (11.2%) approaches for repair of STEs during the study period (n = 107). Main Outcome Measures Postoperative complication rates, recurrence, and diagnosis of IIH. Results The majority of patients were female (64.5%), with a mean body mass index (BMI) of 37 kg/m 2 and mean age of 57 years. Twelve patients (9%) represented reoperations after failed primary repairs. Fourteen percent of patients undergoing primary surgical repair of STE were diagnosed with IIH, compared with 42% of patients undergoing reoperations (p = 0.015). In addition, there was a significant difference in the average BMI of patients undergoing primary (36.4 kg/m 2) versus revision surgery (40.9 kg/m 2 , p = 0.04). Half of those undergoing reoperation were placed on postoperative acetazolamide compared with 11% of patients undergoing primary operations. No patient experienced recurrent leak after reoperation. Conclusion Based on our institutional experience, elevated BMI and the presence of IIH are significant predictors of reoperation for STE. In our experience, acetazolamide is a common adjunct management strategy in addition to reoperation for patients with recurrent cerebrospinal fluid leak in the setting of STE. [ABSTRACT FROM AUTHOR]

Objective: Compare outcomes for subjects who underwent middle cranial fossa (MCF) or transmastoid (TM) repair of superior semicircular canal dehiscence (SSCD). Study Design: Retrospective cohort study. Setting: Quaternary‐care, academic neurotology practice. Methods: Subjects who underwent MCF or TM repair of SSCD between December 1999 and April 2023 were identified. Main outcome measures included demographic data, length of surgery and hospital stay, clinical presentation, and audiometric testing. Results: Ninety‐three subjects (97 ears) who underwent surgery for SSCD met inclusion criteria: 58.8% (57) via MCF, 39.2% (38) via TM, and 2.0% (2) via TM + MCF. Median operative time was shorter for the TM (35) compared to the MCF (29) approach (118 vs 151 minutes, P <.001). Additionally, median hospital stays were shorter for TM (36) compared to the MCF (56) approach (15.3 vs 67.7 hours, P <.001). Overall, 92% (49/53) of MCF and 92% (33/36) of TM surgeries resulted in an improvement or resolution of one or more symptoms (P =.84). There was no significant preoperative to postoperative change in the median air conduction pure‐tone average (PTA), air‐bone gap, or word recognition score in both the MCF and TM groups (P >.05). Improvements of >10 dB in the pre‐ to postoperative absolute change in bone conduction PTA were noted in 3 subjects in the MCF group and 4 subjects in the TM group (P =.49). Conclusion: The TM approach for SSCD demonstrates shorter operative times and length of hospital stay. The TM and MCF approaches have comparable audiometric and clinical outcomes. [ABSTRACT FROM AUTHOR]

Endovascular treatment for isolated dural arteriovenous fistula (DAVF) in the middle cranial fossa (MCF) with pure cortical venous drainage poses challenges, including the absence of a safe access route for transvenous embolization (TVE) and the risk of ischemia to neuro feeding vessels and dangerous anastomosis at the sphenoid wing. Therefore, surgical treatment involving direct blockage of venous reflux via craniotomy is typically preferred. We describe the case of a 63-year-old woman presented with generalized seizures and was diagnosed with a Borden III left MCF-DAVF. Initial TVE was unsuccessful due to an occluded inferior petrosal sinus and a lack of connection between the cavernous sinus and the shunt point. After reducing the shunt flow with transarterial embolization, retrograde TVE through cortical drainage enabled successful treatment for the DAVF. We used a triple coaxial system (4-French guiding sheath, 3.2-French intermediate distal access catheter, and 1.5-French microcatheter) to retrogradely navigate a microcathter from the right jugular vein through the superior sagittal sinus, the vein of Trolard, and into the superficial middle cerebral vein, ultimately achieving shunt occlusion using several coils. This case demonstrates that TVE for MCF-DAVFs with pure cortical venous drainage is feasible when a safe anatomical route is established using appropriate strategies and instruments and provides a safe and effective treatment option for similar cases.

Eosinophilic angiocentric fibrosis (EAF) is a rare, benign fibroinflammatory condition primarily affecting the sinonasal and upper respiratory tract, with a few cases reported beyond these regions. Primary intracranial EAF is rare. To date, only one case of intracranial EAF has been reported; ours is the second. This case report presents a case of EAF in a 55‐year‐old man, initially misdiagnosed as meningioma based on clinical and radiological features. The patient complained of a persistent dull headache for six months without associated neurological symptoms. Brain magnetic resonance imaging revealed a dural‐based lesion with characteristics suggestive of meningioma. However, histopathological examination post‐surgical resection revealed a nodular vascular lesion with concentric angiocentric fibrosis, a distinctive onion skin pattern, and an inflammatory infiltrate rich in eosinophils, plasma cells, and histiocytes. Immunohistochemistry ruled out IgG4‐related disease, and other systemic disorders were ruled out based on combined clinical and histological features. This case underscores the need for considering EAF in the differential diagnosis of dural‐based lesions. Awareness of its potential mimicking of meningioma is crucial for accurate diagnosis and appropriate management, emphasizing the importance of histopathological examination in challenging cases. [ABSTRACT FROM AUTHOR]

Background: Superior Semicircular Canal Dehiscence (SSCD) is a dehiscence of the otic capsule which normally lies over the superior semicircular canal. This database constitutes the largest series of SSCD patients to date. Objective: To determine what preoperative factors, if any, contribute to postoperative outcomes and evaluate symptom resolution in a large SSCD patient cohort. Methods: A single-institution, retrospective chart review collected patient demographics, intraoperative findings, and pre-and postoperative symptoms. Fisher's exact t-test was performed for unpaired categorical variables, with a significance level of p < 0.05. Results: 350 SSCD repairs were performed. The median age was 52 years (range: 17—86 years, ± 6.4 years), and the median follow-up duration was 4.6 months (range: 0.03—59.5 months, ± 6.8 months). Preoperative hearing loss was significantly associated with female sex (p = 0.0028). The most reported preoperative symptoms were tinnitus (77.4%), dizziness (74.0%), autophony (66.3%), amplification (63.7%), and disequilibrium (62.6%). Between patients who received unilateral versus bilateral SSCD repair, the greatest postoperative symptomatic resolution was seen in autophony (74.9%, p < 0.001), amplification (77.3%, p = 0.00027), hyperacusis (77.4%, p = 0.023), hearing (62.9%, p = 0.0063), and dizziness (54.6%, p < 0.001) for patients with unilateral SSCD repair. Conclusion: Surgical repair via the middle cranial fossa approach can significantly resolve auditory, vestibular, and neurological symptoms of patients with SSCD. Although this is one of the largest single-institution SSCD studies to date, future multi-institutional, prospective studies would be beneficial to validate these results. [ABSTRACT FROM AUTHOR]

Objective To study the microanatomic structure of the subtemporal transtentorial approach to the lateral side of the brainstem, and to provide anatomical information that will assist clinicians to perform surgeries on the lateral, circumferential, and petroclival regions of the brainstem. Methods Anatomical investigations were conducted on 8 cadaveric head specimens (16 sides) using the infratemporal transtentorial approach. The heads were tilted to one side, with the zygomatic arch at its highest point. Then, a horseshoe incision was made above the auricle. The incision extended from the midpoint of the zygomatic arch to one third of the mesolateral length of the transverse sinus, with the flap turned towards the temporal part. After removing the bone, the arachnoid and the soft meninges were carefully stripped under the microscope. The exposure range of the surgical approach was observed and the positional relationships of relevant nerves and blood vessels in the approach were clarified. Important structures were photographed and the relevant parameters were measured. Results The upper edge of the zygomatic arch root could be used to accurately locate the base of the middle cranial fossa. The average distances of the star point to the apex of mastoid, the star point to the superior ridge of external auditory canal, the anterior angle of parietomastoid suture to the superior ridge of external auditory canal, and the anterior angle of parietomastoid suture to the star point of the 10 adult skull specimens were 47.23 mm, 45.27 mm, 26.16 mm, and 23.08 mm, respectively. The subtemporal approach could fully expose the area from as high as the posterior clinoid process to as low as the petrous ridge and the arcuate protuberance after cutting through the cerebellar tentorium. The approach makes it possible to handle lesions on the ventral or lateral sides of the middle clivus, the cistern ambiens, the midbrain, midbrain, and pons. In addition, the approach can significantly expand the exposure area of the upper part of the tentorium cerebelli through cheekbone excision and expand the exposure range of the lower part of the tentorium cerebelli through rock bone grinding technology. The total length of the trochlear nerve, distance of the trochlear nerve to the tentorial edge of cerebellum, length of its shape in the tentorial mezzanine, and its lower part of entering into the tentorium cerebelli to the petrosal ridge were (16.95±4.74) mm, (1.27±0.73) mm, (5.72±1.37) mm, and (4.51±0.39) mm, respectively. The cerebellar tentorium could be safely opened through the posterior clinoid process or arcuate protrusion for localization. The oculomotor nerve could serve as an anatomical landmark to locate the posterior cerebral artery and superior cerebellar artery. Conclusion Through microanatomic investigation, the exposure range and intraoperative difficulties of the infratemporal transtentorial approach can be clarified, which facilitates clinicians to accurately and safely plan surgical methods and reduce surgical complications. [ABSTRACT FROM AUTHOR]

Meckel’s cave tumour, a rare benign tumour originating from the Schwann cells surrounding the trigeminal nerve within the Meckel’s cave region, can present with a variety of clinical manifestations. We report a case of a 44-year-old male patient who presented with symptoms of tear deficiency, including dryness, ocular discomfort, and blurred vision. Diagnostic evaluation revealed the presence of a Meckel’s cave tumour harming the trigeminal nerve, leading to alacrimia. This case highlights the association between Meckel’s cave tumour and tear deficiency disorders.

A 42-year-old male presented to the Department of Oral and Maxillofacial Surgery with the chief complaint of pain and stiffness in the right temporomandibular joint (TMJ). The patient’s height was 174 cm and his body weight was 65 kg. The patient’s occupation was heavy equipment operator. According to the patient, the pain had initiated a week prior to his first visit and was exacerbated during mastication. Evaluation of the range of motion revealed extensive crepitus along the right TMJ. The active and passive range of motion were measured at 45 mm and 42 mm, respectively, indicating adequate mouth-opening capacity. Occlusion was also favorable, and no other clinical symptoms were shown intraorally.

Background and Objectives: The adult superficial middle cerebral vein (SMCV) commonly drains into the middle cranial fossa. However, different embryonic types persist, in which the SMCV drains into the lateral sinus. The basal type of SMCV coursing on the middle fossa floor is a scarce variant. Materials and Methods: During a retrospective study of archived computed tomography angiography (CTA) and magnetic resonance angiography (MRA) files, three rare adult cases of the basal or sphenopetrosal type of SMCV were found and further documented. Results: In the first case, which was evaluated via CTA, the basal type of SMCV formed a sagittal loop. It continued on the middle fossa floor, over a dehiscent tegmen tympani, to drain into the lateral sinus. In the second case, documented via MRA, the basal type of SMCV's anterior loop was in the coronal plane and closely related to the internal carotid artery and the cavernous sinus. It continued with the basal segment over a dehiscent glenoid fossa of the temporomandibular joint (TMJ). In the third case, documented via CTA, the initial cerebral part of the SMCV had a large fenestration. The middle fossa floor coursed within a well-configured sulcus of the SMCV and received a tributary through the tympanic roof. Its terminal had a tentorial course. Conclusions: Beyond the fact that such rare variants of the SMCV can unexpectedly interfere with specific approaches via the middle fossa, dehiscences of the middle fossa floor beneath such variants can determine otic or TMJ symptoms. Possible loops and fenestrations of the SMCV should be considered and documented preoperatively. [ABSTRACT FROM AUTHOR]

The arcuate eminence (AE) is an anatomically consistent bony protrusion located on the upper surface of the petrous bone that has been previously studied as a reference for lateral skull base approaches. There is a paucity of information in the neurosurgical literature seeking to improve the safety of the extended middle cranial fossa (MCF) approach using detailed morphometric analysis of the AE. To evaluate the use of the AE as an anatomical landmark to help with early identification of the internal acoustic canal (IAC) in MCF approaches by means of a cadaveric study, using a new morphometric reference termed the "M-point." A total of 40 dry temporal bones and 2 formalin-preserved, latex-injected cadaveric heads were used. The M-point was established as a new anatomic reference by identifying the intersection of a line perpendicular to the alignment of the petrous ridge (PR), originating from the midpoint of the AE, with the PR itself. Subsequent anatomical measurements were performed to measure the distance between M-point and IAC. Additional distances, including PR length and the anteroposterior and lateral AE surfaces, were also measured. The mean distance between the M-point and the center of the IAC was 14.9 mm (SD ± 2.09), offering a safe drilling area during an MCF approach. This study provides novel information on identification of a new anatomic reference point known as the M-point that that can be used to improve early surgical identification of the IAC. [ABSTRACT FROM AUTHOR]

Background: The anterolateral triangle around the cavernous sinus is a surgical skull base triangle used as a neurosurgical landmark essential to skull-based surgeries. There are few reports of its measurements with little attention paid to anatomical variations. Methodology: A total of 15 adult human cadaveric skulls were dissected to expose the anterolateral triangle on both sides. The triangle was defined and measurements of the three borders were taken precisely and the area of each triangle was calculated using Heron's formula. Results: On an average, the length of the anteromedial border is 11.4 (+ 2.2 mm); the length of the posteromedial border is 8.7 (+ 2.6 mm); the length of the lateral border is 13.06 (+ 2.6 mm) and the area of the anterolateral triangle is 48.05 (+ 17.5 mm2). Conclusion: Concise understanding of anterolateral triangle is essential to skull-based surgeries; comprehending its anatomy helps with better surgical planning and provides insight into local pathology. [ABSTRACT FROM AUTHOR]

Different materials and techniques have been proposed for surgical repair of spontaneous middle cranial fossa (MCF) defects. However, conclusive evidence supporting their selection and impact on clinical outcomes is lacking. The study aims to conduct a systematic review and meta-analysis on materials and techniques employed to repair MCF defects and evaluate complications and rates of recurrent cerebrospinal fluid (CSF) leaks. A PRISMA-guided systematic review and meta-analysis were performed using MESH terms and specific keywords including studies published before May 2022. Primary outcomes included recurrence of CSF leak and complication rates by type of reconstructive material and technique utilized. Meta-analyses of proportions were performed using random effects and confidence intervals for individual proportions were calculated using the Clopper-Pearson method. Twenty-nine studies were included (n = 471 cases). Materials employed for repair were categorized according to defect size: 65% of defects were of unknown size, 24% were small (< 1 cm), and 11% were large (≥ 1 cm). Rigid reconstruction (RR) was significantly favored over soft reconstruction (SR) for larger defects (94% of cases, p < 0.05). Complications and recurrent CSF leak rates of SR and RR techniques were comparable for defects of all sizes (p > 0.05). Complication rates reported for these procedures are low regardless of technique and material. RR was universally preferred for larger defects and analysis of complication and recurrence rates did not reveal differences regardless of defect size. While RR was more frequently reported in smaller defects, SR was used by several centers, particularly for smaller MCF floor defects. [ABSTRACT FROM AUTHOR]

The pneumatization of the articular portion of the temporal bone is an anatomical variant that can modify the barrier between the articular space and the middle cranial fossa. Thus, this study aimed to identify the presence and degree of pneumatization, as well as the existence of pneumatic cell dehiscence towards the extradural or articular space determining whether it could lead to direct communication between the articular and extradural spaces. Hence, One-hundred skull computed tomography images were selected. The presence and extension of pneumatization were classified according to scores 0, 1, 2, and 3. Dehiscence towards extradural and articular spaces was recorded. In total, 200 TMJ from 100 patients were assessed and 40.5% of pneumatization cases were observed. The most prevalent score was 0 (restricted to the mastoid process), while the least prevalent score was 3 (extending beyond the crest of articular eminence). Dehiscence of the pneumatic cells towards the extradural space is more common than towards the articular space. One complete communication between the extradural and articular spaces was observed. Considering the results, it was concluded that to avoid neurological and ontological complications, awareness of the potential anatomical communications between articular and extradural spaces, particularly in patients with extensive pneumatisation, is necessary. [ABSTRACT FROM AUTHOR]

Abstract Background Juvenile nasopharyngeal angiofibroma (JNA) is an infrequent, highly vascular tumor that predominantly affects male adolescents. Although benign, it rarely may exhibit invasive growth, leading to significant morbidity, as in our case presentation. Diagnosis relies on clinical evaluation and imaging, with MR and CT playing vital roles in confirming the tumor's presence, determining its extent, and aiding in treatment planning. MR shows a mass with signal voids at T2-weighted images and intense contrast enhancement at T1-weighted images, while CT shows bone remodeling and destruction. A biopsy is usually avoided due to bleeding risks. Case presentation We present a case of a 16-year-old male with nasal obstruction and recurrent epistaxis from the right nostril, headache, and mucopurulent rhinorrhea. Furthermore, he had vision impairment in the right eye for one week associated with proptosis and periorbital swelling. MR and CT imaging evidenced the presence of JNA with extensive involvement in the nasal cavity, nasopharynx, pterygopalatine fossa, and infratemporal fossa. Moreover, the mass invaded the orbital apex and middle cranial fossa contacting the cavernous sinus and internal carotid artery. Preoperative embolization and complete surgical resection were performed. No complications occurred in the postoperative period and histopathological analysis confirmed the diagnosis of JNA. No recurrences were found at 12 months MR follow-up. Conclusions Early detection and accurate imaging evaluation are essential for the effective management of JNA. Regular post-treatment MR follow-ups are crucial to detect recurrences or assess fibrosis stability. MR and CT continue to be indispensable tools in the diagnosis and follow-up of JNA.

Background: The soft tissue dissection for the middle fossa approach requires adequate management of the neuro, vascular, and muscular structures in order to maximize exposure and diminish morbidities. Methods: An incision anterior to the tragus is performed, extending from the zygomatic process to the superior temporal line. The superior temporal artery is exposed, followed by a subfascial dissection of the frontalis nerve. The temporal muscle is dissected and released from the zygoma. All cranial landmarks are exposed for the 5 × 5 cm temporal fossa craniotomy. Conclusion: This novel approach provides a safe and adequate access to perform an extended middle fossa craniotomy. [ABSTRACT FROM AUTHOR]

Background: Juvenile nasopharyngeal angiofibroma (JNA) is an infrequent, highly vascular tumor that predominantly affects male adolescents. Although benign, it rarely may exhibit invasive growth, leading to significant morbidity, as in our case presentation. Diagnosis relies on clinical evaluation and imaging, with MR and CT playing vital roles in confirming the tumor's presence, determining its extent, and aiding in treatment planning. MR shows a mass with signal voids at T2-weighted images and intense contrast enhancement at T1-weighted images, while CT shows bone remodeling and destruction. A biopsy is usually avoided due to bleeding risks. Case presentation: We present a case of a 16-year-old male with nasal obstruction and recurrent epistaxis from the right nostril, headache, and mucopurulent rhinorrhea. Furthermore, he had vision impairment in the right eye for one week associated with proptosis and periorbital swelling. MR and CT imaging evidenced the presence of JNA with extensive involvement in the nasal cavity, nasopharynx, pterygopalatine fossa, and infratemporal fossa. Moreover, the mass invaded the orbital apex and middle cranial fossa contacting the cavernous sinus and internal carotid artery. Preoperative embolization and complete surgical resection were performed. No complications occurred in the postoperative period and histopathological analysis confirmed the diagnosis of JNA. No recurrences were found at 12 months MR follow-up. Conclusions: Early detection and accurate imaging evaluation are essential for the effective management of JNA. Regular post-treatment MR follow-ups are crucial to detect recurrences or assess fibrosis stability. MR and CT continue to be indispensable tools in the diagnosis and follow-up of JNA. [ABSTRACT FROM AUTHOR]

Simple Summary: The popularity that transorbital approaches (TOAs) gained in recent years has allowed their diffusion into skull base surgery. However, for their correct application, it is essential to know the potential and the limits of this group of transorbital routes, as well as the knowledge of anatomy from this relatively new surgical perspective. In this paper, the authors illustrate step-by-step the superior eyelid transorbital approach from a macroscopic and endoscopic perspective, highlighting the main anatomical relationships to understand the application of this surgical route for the treatment of skull base pathologies. Surgical cases are provided to illustrate indications for this approach. Background: The transorbital approaches (TOAs) have acquired growing notoriety, thanks to their ability to offer alternative corridors to the skull base. However, the limited access and the unfamiliarity with this surgical perspective make recognition of key landmarks difficult, especially for less experienced surgeons. The study wants to offer a detailed description of the anatomy to comprehend the potential and limitations of TOAs. Methods: Measurements of the orbit region and the surrounding areas were performed on two hundred high-resolution CT scans and thirty-nine dry skulls. Five specimens were dissected to illustrate the TOA, and one was used to perform the extradural clinoidectomy. Three clinical cases highlighted the surgical applications. Results: A step-by-step description of the key steps of the TOA was proposed and a comparison with the transcranial anterior clinoidectomy was discussed. The mean work distance was 6.1 ± 0.4 cm, and the lateral working angle increased 20 ± 5.4° after removing the lateral orbital rim. Conclusions: TOAs are indicated in selected cases when tumor involves the lateral portion of the cavernous sinus or the middle skull base, obtaining a direct decompression of the optic nerve and avoiding excessive manipulation of the neurovascular structures. Comprehension of surgical anatomy of the orbit and its surrounding structures is essential to safely perform these approaches. [ABSTRACT FROM AUTHOR]

Introduction: The foramen lacerum is located in the middle cranial fossa and transmits a number of nerves and blood vessels. Occlusion can result in the compression of the neurovascular bundle, and the foramen has been reported to be involved in the spread of tumours into the cranium. Aim: The aims of the present study was to describe the morphology of the foramen lacerum and to compare the anatomical parameters on the left and right sides of the skull. Also, the significance of the anatomical parameters in male versus female skulls and right side versus left side of the skull where studied. Materials and Methods: This cross-sectional study was conducted in May and June 2023 using 62 dry skulls (124 foramen lacerum) available in the Department of Anatomy at Gautam Buddha Chikitsa Mahavidyalay, a tertiary care teaching institute in Dehradun, Uttarakhand, India. The anatomical parameters, including the Anteroposterior (AP) and transverse diameters, were recorded using a calibrated digital Vernier caliper. The shape of the foramen was also observed. The mean and standard deviation of the recorded parameters were obtained. Results: Out of the 62 skulls, 41 were males and 21 were females, resulting in a male-to-female ratio of 1.8:1. The mean AP diameter on the Right Side (RT) and Left Side (LT) in males was 6.26 mm and 6.24 mm, respectively, while in females, the mean diameter was 4.97 mm (RT) and 5.4 mm (LT). The mean transverse diameter recorded in the present study was 6.14 mm (RT) and 6.2 mm (LT) in males, while in females, this measurement was 5.88 mm on both sides. The most common shape of the foramen lacerum observed in the study was bilaterally round, in both males and females. Conclusion: There are morphological differences in the AP diameter between male and female skulls, with males having a larger AP diameter on their right side and females having larger AP diameter on their right side. The overall size of the foramen lacerum was smaller in the present study, indicating a higher likelihood of neurovascular bundle compression with age. The recent advances in skull base surgery warrant further and larger studies on this neglected yet important foramen to gather more data on its morphometric variations in different geographical regions.

Adequate epidural procedures and anatomical knowledge are essential for the technical success of skull base surgery. We evaluated the usefulness of our three-dimensional (3D) model of the anterior and middle cranial fossa as a learning tool in improving knowledge of anatomy and surgical approaches, including skull base drilling and dura matter peeling techniques. Using a 3D printer, a bone model of the anterior and middle cranial fossa was created based on multi-detector row computed tomography data, incorporating artificial cranial nerves, blood vessels, and dura mater. The artificial dura mater was painted using different colors, with 2 pieces glued together to allow for the simulation of peeling the temporal dura propria from the lateral wall of the cavernous sinus. Two experts in skull base surgery and 1 trainee surgeon operated on this model and 12 expert skull base surgeons watched the operation video to evaluate this model subtlety on a scale of 1 to 5. A total of 15 neurosurgeons, 14 of whom were skull base surgery expert, evaluated, scoring 4 or higher on most of the items. The experience of dural dissection and 3D positioning of important structures, including cranial nerves and blood vessels, was similar to that in actual surgery. This model was designed to facilitate teaching anatomical knowledge and essential epidural procedure-related skills. It was shown to be useful for teaching essential elements of skull-base surgery. [ABSTRACT FROM AUTHOR]

Introduction The wide range of anatomical variability of the structures of the middle cranial fossa (MCF) and the lack of reliable surgical landmarks contribute to a high level of complications in the surgical treatment of vestibular schwannomas. We hypothesized that the cranial phenotype influences the shape of the MCF, the orientation of the pyramid of the temporal bone, and the relative topography of the internal acoustic canal (IAC). Methods The skull base structures were studied on 54 embalmed cadavers and 60 magnetic resonance images of the head and neck by photo modeling, dissection, and three-dimensional analysis techniques. By the value of the cranial index, all specimens were subdivided into dolichocephalic, mesocephalic, and brachycephalic groups for comparison of variables. Results The length of the superior border of the temporal pyramid (SB), the apex to squama distance, and the width of the MCF all peaked in the brachycephalic group. The value of the angle between the SB and the axis of the acoustic canal varied from 33 to 58 degrees; it peaked in the dolichocephalic group and showed its smaller value in the brachycephalic one. The pyramid to squama angle had reversed distribution and dominated in the brachycephalic group. Conclusion The cranial phenotype influences the shape of the MCF, temporal pyramid, and IAC. Presented in this article data help specialists operating on the vestibular schwannoma to localize the IAC based on the individual shape of a skull. [ABSTRACT FROM AUTHOR]

The superior dislocation of the condyle into the cranium occasionally requires invasive procedures due to the absence of a timely diagnosis. This review analyzed the available clinical data to provide information on treatment decisions. The reports were assessed using electronic medical databases from inception to 31 October 2022. A total of 116 cases from 104 studies were assessed; among the patients, 60% and 87.5% of the affected women and men required open reduction, respectively. The ratio of closed to open procedures within 7 days after injury was maintained; however, closed reduction decreased over time, and all cases required open reduction after 22 days. Eighty percent of the patients with a total intrusion of the condyle required open reduction, whereas the frequency for both procedures was comparable in the remaining patients. Open reduction was significantly more frequently performed for men (p = 0.026, odds ratio; 4.959, 95% confidence interval; 1.208–20.365) and less frequently performed in cases with partial intrusion (p = 0.011; odds ratio: 0.186; 95% confidence interval: 0.051–0.684); the frequency varied according to the time until treatment (p = 0.027, odds ratio; 1.124, 95% confidence interval; 1.013–1.246). Appropriate diagnostic imaging and prompt diagnosis are indispensable for minimally invasive treatment of this condition. [ABSTRACT FROM AUTHOR]

Abstract Background Facial nerve schwannomas account for about 0.8% of all petrous mass lesions. Schwannomas of the greater superficial petrosal nerve (GSPN) are a rare subtype with few case-reports up to date. Case presentations A retrospective analysis of clinical outcomes, radiographic findings and postoperative complication between June 2007 and December 2020 was performed. Four cases of GSPN schwannomas were reported. The presenting symptoms were facial nerve palsy and hearing loss. Imaging studies showed a subtemporal mass on the anterosuperior aspect of the petrous bone, in one case with extraordinary petrous bone and mastoid infiltration and destruction. Three cases were removed through a subtemporal extra- or intradural approach, one case via a combined pre- and retrosigmoid approach. Improvement of facial nerve palsy occurred in one case; new hearing loss was observed in another case. Xeropthalmia was a short-term temporary deficit in three cases. Short- to mid-term follow-up of the patients has not shown any tumor recurrence. Conclusions GSPN schwannomas are rare entities presenting with heterogenous symptoms. Our surgical findings emphasize safe resection. Complete remission is possible by GTR. Since the small data set limits the expressiveness of statements regarding standard of care and alternative therapy options, additional data is needed.

Background For endoscopic fenestration of middle cranial fossa arachnoid cysts (MCFACs), the decisions on the location and number of stomas are key issues. However, research on this particular topic has been limited. Thus, this study aimed to compare single- versus multiple-stoma endoscopic fenestration for treating Galassi type III MCFACs. Methods This retrospective study included 86 patients with Galassi type III MCFACs treated with endoscopic fenestration. Single-stoma fenestration to the basal cistern was performed in 37 cases, whereas multiple-stoma fenestration to the basal cistern and the carotid cistern was performed in 49 cases. Clinicoradiologic profiles and follow-up data were analyzed. Results The rate of symptom relief was 83.7% (72/86), and the rate of cyst shrinkage was 96.5% (83/86). Postoperative ipsilateral subdural effusion, which was significant (p = 0.042), and noninfectious fever were the two most common complications in the single- and multiple-stoma groups. No significant differences in intraoperative nerve injury, vascular injury, proportion of cases with cyst reduction, and symptom remission rate were observed between the two groups. The rates of cyst recurrence and secondary surgery in the single-stoma group were higher than those in the multiple-stoma group, although the difference was not significant. Conclusion Endoscopic fenestration is an effective and minimally invasive approach for treating Galassi type III MCFACs. Single- and multiple-stoma endoscopic fenestrations have the same curative effect. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of the study is to evaluate MRI findings of middle fossa arachnoid cysts in children according to Galassi classification and determine the differences between types and to assess the morphological changes in cysts during follow-up imaging. Methods: MR images of 266 middle fossa arachnoid cysts of 255 pediatric patients were evaluated by two experienced radiologists retrospectively. MRI features including the sidedness of the cyst, Galassi type, parenchymal compression findings (cortical flattening and white matter compression), bone remodeling, and midline shift were evaluated on axial T2- and T1-weighted images. Follow-up MRI and available CSF flow MR imaging data were evaluated for change in cyst size and cisternal connections, respectively. Results: The most common type was type 1 according to Galassi classification. The accompanying bone remodeling and white matter compression had a higher incidence in Galassi type 2 and 3 groups than Galassi type 1. Mean age of patients with bone remodeling and white matter compression was significantly higher in patients with Galassi type 1. All patients with cyst enlargement were younger than 2 years of age, and all of them were Galassi type 1. Cisternal connection was demonstrated in 7 patients. Conclusion: While parenchymal compression and bone remodeling are expected findings in Galassi type 2 and 3 cysts, these features can also be seen in smaller Galassi type 1 cysts, regardless of size. Most of the middle fossa arachnoid cysts remain stable on follow-up imaging, and the increase in size is not an expected finding, especially in older children. [ABSTRACT FROM AUTHOR]

Background: Facial nerve schwannomas account for about 0.8% of all petrous mass lesions. Schwannomas of the greater superficial petrosal nerve (GSPN) are a rare subtype with few case-reports up to date. Case presentations: A retrospective analysis of clinical outcomes, radiographic findings and postoperative complication between June 2007 and December 2020 was performed. Four cases of GSPN schwannomas were reported. The presenting symptoms were facial nerve palsy and hearing loss. Imaging studies showed a subtemporal mass on the anterosuperior aspect of the petrous bone, in one case with extraordinary petrous bone and mastoid infiltration and destruction. Three cases were removed through a subtemporal extra- or intradural approach, one case via a combined pre- and retrosigmoid approach. Improvement of facial nerve palsy occurred in one case; new hearing loss was observed in another case. Xeropthalmia was a short-term temporary deficit in three cases. Short- to mid-term follow-up of the patients has not shown any tumor recurrence. Conclusions: GSPN schwannomas are rare entities presenting with heterogenous symptoms. Our surgical findings emphasize safe resection. Complete remission is possible by GTR. Since the small data set limits the expressiveness of statements regarding standard of care and alternative therapy options, additional data is needed. [ABSTRACT FROM AUTHOR]

The superficial middle cerebral vein (SMCV) commonly drains in the cavernous sinus. Its different drainage variants include preserved segments of the primitive tentorial sinus. In any of these variants, the terminal venous segment of SMCV passes on the base of the skull. The archived computed tomography angiograms of a 58-year-old female case were documented anatomically. On the left side was found the sinus of the lesser sphenoidal wing converging with the middle meningeal vein to form a venous channel located within the Sylvian fissure at 4 mm laterally to the cavernous sinus and trigeminal cavum. That venous channel was thus termed the 'laterocavernous vein'. It drained posteriorly within the superior petrosal sinus. This aberrant vein could interfere unpleasantly with pterional neurosurgical approaches for the Sylvian fissure, cavernous sinus or trigeminal ganglion. [ABSTRACT FROM AUTHOR]

Management of vestibular schwannoma (VS) is a complex process aimed at identifying a clinical indication for fractionated stereotactic radiotherapy (sRT) or microsurgical resection or wait and scan (WS). The aim of the review was to clarify which patient and tumor parameters may lead to different therapeutic choices, with a view to a personalized VS approach. A systematic review according to Preferred Reporting Items for Systematic Review and Meta-Analysis criteria was conducted between February and March 2022. The authors defined six parameters that seemed to influence decision-making in VS management: 1-incidental VS; 2-tumor size; 3-tumor regrowth after sRT; 4-subtotal resection; 5-patients' age; 6-symptoms. The initial search yielded 3532 articles, and finally, 812 articles were included. Through a qualitative synthesis of the included studies, management strategies were evaluated and discussed. An individualized proposal of procedures is preferable as compared to a single gold-standard approach in VS decision-making. The most significant factors that need to be considered when dealing with a VS diagnosis are age, tumor size and hearing preservation issues. [ABSTRACT FROM AUTHOR]

Objective: To investigate the accuracy in localization of the anterosuperior margin of TSSJ by using the intersection point between the squamosal and parietomastoid sutures (A point) and the intersection of the squamosal suture and supramastoid crest (B point) as bony landmarks. Materials and Methods: The A and B points were marked on the inner surface of a skull by using the transillumination technique. The anatomical relationship between the projected A point, B point, and groove of TSSJ was investigated in 60 dried Thai human skulls (120 sides). Results: Of the 120 sides, the projected A points were located exactly on the anterosuperior margin of the TSSJ in 38 (31.7%) instances and adjacent (above and below) the anterosuperior margin in 82 (68.3%) cases. Of the 118 sides with identifiable supramastoid crests, the projected B points were located precisely on the anterosuperior margin of TSSJ in 60 (50.8%) cases and above the anterosuperior margin of the TSSJ in 57 (48.3%) cases. Hence, the projected B point was a more reliable bony landmark for localizing the anterosuperior margin of the TSSJ when compared with the projected A point (p = 0.003, OR 2.2, and 95% CI =1.3-3.8). Conclusion: The B point is a more reliable temporal bone landmark for localization of the TSSJ than the A point. In temporal craniotomy, an initial burr hole at the B point is relatively safe and carries a very low risk of inadvertent venous sinus injury.

Solitary fibrous tumors (SFTs) exceptionally occur at the middle cranial fossa. A midline search from January 1997 up to June 2021 selected 16 articles for a total of 19 patients, where the tumor attachment was completely or largely (>75%) at the middle cranial fossa. The unique personal case concerns a 35 years old woman complaining of left hypoacusia and moderate left facial paresis. A high grade SFT of the left middle fossa was resected, with no recurrence 8 years after surgery and irradiation. The 20 patients of the review, including ours, are 11 men and 9 women with a median age of 47 years. The location was mainly intradural (47%) or extra-intradural (42%); the invasion of the petrous bone was evidenced in a half of the patients. Symptoms of involvement of the Vth, VIIth and VIIIth cranial nerve were more frequent (3/4 of the cases). Variable T2 signal, lobulated margins and inhomogeneous enhancement were the most frequent MRI features. Histologically most tumors (70%) were WHO grade III and 23% grade I. A gross total resection was possible in 55% of the cases. The recurrence rate is significant (23,5%). Older patient age (>50 years), large tumor size, incomplete resection and high WHO grade histology are significant prognostic factors for recurrence. However, the outcome is sometimes unpredictable. Thus, a follow-up by serial MRI studies is strongly advisable.

Objectives/Hypothesis: To review hearing preservation after microsurgical resection of sporadic vestibular schwannomas according to tumor size. Study Design: Retrospective cohort. Methods: Baseline, intraoperative, and postoperative patient and tumor characteristics were retrospectively collected for a cohort who underwent hearing preservation microsurgery. Serviceable hearing was defined by a pure tone average ≤50 dB and word recognition score ≥50%. Results: A total of 243 patients had serviceable hearing preoperatively. Fifty (21%) tumors were confined to the internal auditory canal, and the median tumor size was 16.2 mm (interquartile range [IQR] 11.3–23.2) for tumors with cerebellopontine angle extension. Serviceable hearing was maintained in 64% of patients with tumors confined to the internal auditory canal, 28% with cerebellopontine angle extension <15 mm, and 9% with cerebellopontine angle extension ≥15 mm. On multivariable analysis, the odds ratios of acquiring nonserviceable hearing postoperatively for tumors extending <15 mm and ≥15 mm into the cerebellopontine angle were 5.75 (95% confidence interval [CI] 2.13–15.53; P <.001) and 22.11 (95% CI 7.04–69.42; P <.001), respectively, compared with intracanalicular tumors. Conclusions: The strongest predictor of hearing preservation with microsurgery after multivariable adjustment is tumor size. Approximately 10% of patients with tumors ≥15 mm of cerebellopontine angle extension will retain serviceable hearing after microsurgery. Furthermore, hearing preservation techniques offer cochlear nerve preservation and cochlear patency allowing for possible future cochlear implantation. An attempt at hearing preservation, including avoiding surgical approaches that necessarily sacrifice hearing, is worthwhile even in larger tumors if serviceable hearing is present preoperatively. Level of Evidence: 4 Laryngoscope, 132:1657–1664, 2022 [ABSTRACT FROM AUTHOR]

Background: Extradural transcranial release of the meningo-orbital band occupying the lateral part of the superior orbital fissure is used to approach the orbital apex and middle cranial fossa. The authors tested the feasibility of the release of the meningo-orbital band via an endonasal transmaxillary approach.Materials and Methods: Five injected cadaveric heads were assessed for dimensions of superior orbital fissure by computerized tomography. An endonasal transsphenoid transpterygoid approach was done to the superior orbital fissure and annulus of Zinn medially, down to the maxillary nerve. The periorbita was dissected superolaterally to expose the greater wing of the sphenoid and the meningo-orbital band. The superior orbital fissure was decompressed inferiorly by drilling the greater wing of the sphenoid and the maxillary strut after transposition of the maxillary nerve. The meningoorbital band was cut at the junction of the lateral part of the superior orbital fissure and the periorbita exposing the frontotemporal dural junction. The edge of the lesser wing of the sphenoid was drilled toward the annulus of Zinn and the optic canal. The temporal lobe dura was separated from the periorbita and lateral cavernous dural wall at the meningo-orbital band and the ophthalmic nerve.Results: The superior orbital fissure had an oblique angle (mean: 39 ± 2.75 degrees) to the midsagittal plane, the length of its lateral part corresponding to the meningo-orbital band was (mean: 6.08 ± 2.58 mm) and the distance from its lateral end to midline was (mean 2.97 ± 0.11 cm). The meningo-orbital band was released in 10 cadaveric head sides with a distinct plane between the periorbita and the dura propria. Transmaxillary endoscopy provided less orbital retraction and better visualization of the lateral wall of the cavernous sinus.Conclusion: Endonasal transmaxillary release of the meningoorbital band is feasible, allowing exposure of the orbital apex and the middle cranial fossa. [ABSTRACT FROM AUTHOR]

Introduction: Primary IgG4-related disease (IgG4-RD) of the temporal bone is a rare condition. Unlike typical petrous apicitis or Gradenigo syndrome, our patient presented exclusively with unilateral cranial nerve VI palsy and symptoms of diplopia. Skull base imaging demonstrated a destructive bony lesion in the petrous apex. Imaging and systemic investigations were insufficient to support a diagnosis. The diagnosis was achieved histologically after acquiring the specimen by middle cranial fossa craniotomy and temporal bone biopsy. This case report is thought to be the first published description of a diagnosis of IgG4-RD proven with the middle cranial fossa approach. Case Report: We describe a 29-year-old female with primary IgG4-RD of the petrous apex of the temporal bone. This patient presented with a few-month history of left-sided headache and recent-onset diplopia due to paralysis of cranial nerve VI. Imaging demonstrated a petrous apex lesion, and comprehensive systemic investigations could not reach a diagnosis. A middle cranial fossa craniotomy and a biopsy of the temporal bone lesion were undertaken to establish the diagnosis. Histological confirmation of IgG4-RD was proven. Following treatment with corticosteroids, the patient experienced complete recovery and resolution of her symptoms. Conclusion: This study describes a case of primary IgG4-RD of the petrous apex of the temporal bone that presented with diplopia and was diagnosed by middle fossa craniotomy and temporal bone biopsy. To the best of our knowledge, this is the first case description where primary diagnosis was made based on middle cranial fossa craniotomy and temporal bone biopsy. [ABSTRACT FROM AUTHOR]

Skull base meningiomas threatening the optic nerves may require performing an extradural anterior clinoidectomy (EAC) to optimally decompress the optic pathways. The present study evaluated the functional results and morbidity after surgical resection of skull base meningiomas including EAC, focusing on visual acuity (VA) and oculomotricity. Eighty-seven consecutive patients harboring skull base meningiomas who underwent surgical resection that included an EAC between 2003 and 2020 were retrospectively analyzed (86% women, median age 53 years). Decreased visual acuity (DVA) was graded as functional (VA ≥ 5/10) and nonfunctional (VA < 5/10). Statistical analyses were performed on VA and oculomotor nerve (OcN) dysfunction. Ninety surgical procedures were performed. Meningiomas were located at the anterior clinoid process (39%), cavernous sinus (31%), and spheno-orbital (30%) levels. Patients with a preoperative functional vision (normal or functional DVA) had a 90.9% (IC95% = [84.0; 97.8]) probability of preserving it at 6 months and an 84.8% (IC95% = [76.2; 93.5]) probability at last follow-up. Patients with preoperative nonfunctional vision (nonfunctional DVA or blindness) had a 19.0% (IC95% = [2.3; 35.8]) probability of recovery of functional vision at 6 months and a 23.8% (IC95% = [5.6; 42.0]) probability at last follow-up. Preoperative DVA was significantly associated with early postoperative DVA in univariate analyses (p = 0.04). Concerning the OcN, 65% of the patients experienced a postoperative dysfunction, and 78% of those cases recovered. Our study confirms EAC as a useful technical option for skull base meningiomas threatening the optic nerve, especially relevant for patients with preoperative functional vision, and supports early surgical management for these meningiomas. [ABSTRACT FROM AUTHOR]

IntroductionPrimary IgG4-related disease (IgG4-RD) of the temporal bone is a rare condition. Unlike typical petrous apicitis or Gradenigo syndrome, our patient presented exclusively with unilateral cranial nerve VI palsy and symptoms of diplopia. Skull base imaging demonstrated a destructive bony lesion in the petrous apex. Imaging and systemic investigations were insufficient to support a diagnosis. The diagnosis was achieved histologically after acquiring the specimen by middle cranial fossa craniotomy and temporal bone biopsy. This case report is thought to be the first published description of a diagnosis of IgG4-RD proven with the middle cranial fossa approach.Case ReportWe describe a 29-year-old female with primary IgG4-RD of the petrous apex of the temporal bone. This patient presented with a few-month history of left-sided headache and recent-onset diplopia due to paralysis of cranial nerve VI. Imaging demonstrated a petrous apex lesion, and comprehensive systemic investigations could not reach a diagnosis. A middle cranial fossa craniotomy and a biopsy of the temporal bone lesion were undertaken to establish the diagnosis. Histological confirmation of IgG4-RD was proven. Following treatment with corticosteroids, the patient experienced complete recovery and resolution of her symptoms.ConclusionThis study describes a case of primary IgG4-RD of the petrous apex of the temporal bone that presented with diplopia and was diagnosed by middle fossa craniotomy and temporal bone biopsy. To the best of our knowledge, this is the first case description where primary diagnosis was made based on middle cranial fossa craniotomy and temporal bone biopsy.

Background: Amyloidoma is a rare mass lesion formed by abnormal deposition of amyloid proteins. There are 25 reported cases of Meckel's cave amyloidoma primarily involving the trigeminal nerve alone. Case presentation: A 55-year-old woman presented with one year of right-sided trigeminal neuropathy and facial weakness. On examination, there was right-sided V1-V3 dysesthesia and partial right facial paralysis. Magnetic resonance imaging (MRI) showed a right-sided enhancing 1.5 cm × 0.7 cm × 0.4 cm mass in Meckel’s cave. The mastoid segment of the right facial nerve demonstrated focal enhancement. A biopsy of the Meckel’s cave lesion was performed via a right lateral transorbital approach. Results: Histologic sections showed pale eosinophilic amorphous material birefringent to polarized light in Congo red stain. Mass spectrometry confirmed a lambda light chain amyloidoma. Extensive workup did not reveal evidence of systemic amyloidosis, consistent with localized central nervous system (CNS) amyloidoma in Meckel’s cave. The patient remains stable at nine months. Conclusion: This is a rare case of primary Meckel’s cave amyloidoma affecting cranial nerves V and VII. A minimally invasive lateral transorbital approach was employed to access the tumor in the middle cranial fossa. Amyloidoma should be considered in the differential diagnosis of lesions involving Meckel’s cave and multiple cranial nerves.

We describe a 58-year-old man with a unique complication of chronic mandibular osteomyelitis. He presented with a unilateral facial nerve palsy and a non-traumatic dislocation of the mandibular condyle into the middle cranial fossa combined with a temporal lobe abscess. An odontogenic infection had already been festering for 18 months. After stereotactic puncture, P. Aeruginosa was cultured out of the brain abscess and the patient was treated with a culture-based antibiotic therapy followed by condylectomy and myofascial temporalis flap. One year after the surgery, the patient had a partial ossification of the glenoid fossa, recovered mouth opening and sufficient function. This report shows that the rare complication of chronic mandibular osteomyelitis with concurrent brain abscess can be treated successfully using a combination of aggressive long-term culture-based antibiotic treatment and a multidisciplinary surgical approach.

Objectives: To analyse clinical, surgical and postoperative outcome perspectives of tumors occupying both middle and posterior cranial fossa. Materials and Methods: This retrospective cohort study includes 23 patients operated for tumors involving both middle and posterior cranial fossa in our department between August 2016 and August 2020. Each patient was evaluated for age, sex, co morbidities, tumour histopathology, clinical presentation, radiological characteristics, surgical and outcome characteristics. Unpaired t- test and chi-square test was used for statistical analysis. P < 0.05 was considered statistically significant. Results: The mean age was 46 years (range 40–57 years), with the majority of patients being female (56.5%). Most tumors (65.3%) were trigeminal schwannoma, with the remaining being vestibular schwannoma (21.7%), facial schwannoma (8.7%) and epidermoid (4.3%). The most commonly used surgical approach was the retrosigmoid approach (30.4%) and combined approach (30.4%). Gross total resection (GTR) was done in 14 patients while subtotal resection (STR) was done in 9 patients. STR was significantly associated (p

The classical middle cranial fossa approach (MCFA) for vestibular schwannoma (VS) removal often requires a large incision and craniotomy, excessive temporal lobe manipulation, and a longer recovery. We describe a keyhole MCFA (KMCFA) with endoscopic assistance that allows for adequate access with minimal temporal lobe manipulation, resulting in a fast recovery and an invisible scar. Eight sides of four cadaveric heads were dissected through the endoscopic-assisted KMCFA to access the internal auditory canal (IAC). Furthermore, five patients with intracanalicular VS underwent tumor removal with the endoscopic-assisted KMCFA. During the endoscopic-assisted KMCFA with fine instruments, a 3-cm supra-auricular incision and a 2-cm diameter keyhole craniotomy achieved exposure of the entire length of the IAC in all cadaveric dissections without unintended violation of the cochlea, semicircular canal, and facial nerve. The gross tumor was totally removed in five patients with no major postoperative complications. The surgical time was reduced, the hearing outcomes were similar to those of the classical MCFA, and the scar was invisible 1 month after the surgery. The endoscopic-assisted KMCFA permits intracanalicular VS removal in a safe, efficient, and cosmetic way. For small intracanalicular VSs, this approach can replace the classical MCFA when indicated. [ABSTRACT FROM AUTHOR]

Introduction: Foramen ovale which is present in the cranial cavity usually connects infratemporal fossa with the middle cranial fossa. This foramen is clinically quite helpful in several diagnostic and surgical procedures such as FNA through trans-facial approach which is supportive in the diagnosis of squamous cell carcinoma, meningioma and to evaluate the spread of many tumours. Materials and Methodology: The present study is designed as a cross-sectional study which was undertaken on fully ossified skulls of north Indian population which constituted 75 dry, adult human skulls (39 males & 38 Females) obtained from Department of Anatomy at Index Medical College Hospital and Research centre, Indore, Madhya Pradesh. All the bones should be completely ossified and free from any congenital or pathological defects. Those bones which are deformed or malformed should be excluded from the study. The present study is designed as a cross-sectional study which was undertaken on fully ossified skulls of north Indian population which constituted 75 dry, adult human skulls (39 males & 38 Females) obtained from Department of Anatomy at Index Medical College Hospital and Research centre, Indore, Madhya Pradesh. All the bones should be completely ossified and free from any congenital or pathological defects. Those bones which are deformed or malformed should be excluded from the study. Results: The bilaterally present foramen ovale was seen in almost all skulls. In this study the shape of the foramen ovale was oval in 56.70% cases while almond shaped in 28.65 % cases, round in 10.97%, irregular in 3.65% cases as tabulated in Table-1. Out of 75 skull the bilateral symmetric shape was seen in 35 skulls (70%) but the asymmetry in size i.e., dimensions in terms of length and width were bilaterally different in 100% of skulls. The 3.65% irregular foramen included one foramen showing confluence with the adjacently present foramen spinosum unilaterally on the left side. One of the skulls showed a confluence of the foramen ovale with the foramen spinosum and foramen lacerum bilaterally. The mean length and width of foramen ovale in male skulls was 7.561±1.123 and 7.640±1.194and 5.244±0.950 and 5.128±0.827 in the female skulls. However, the difference between the dimensions was statistically highly significant in the two sexes. (Table-2). Conclusion: To conclude, the shape of the foramen ovale was continuously variable, typically oval in most of the skulls (56.70%) followed by almond shaped. There was no significant difference in measurements of various metric parameters between right and left sides of foramen ovale (p>0.05) but highly significant difference was observed between male and female dimensions of all metric parameters. (p<0.001). The foramen ovale does not exhibit bilateral symmetry but sexual dimorphism is evident. The observed data might be helpful for surgical practices for references in the near future. [ABSTRACT FROM AUTHOR]

Superior semicircular canal dehiscence (SSCD) is an abnormality of the otic capsule, which normally overlies the superior semicircular canal. Surgical management is indicated in patients with persistent and debilitating symptoms. Given the complexity of the disease, there are patients who experience less favorable surgical outcomes and require revision surgery. The purpose of this study was to report to the rate of postoperative symptomatic improvement in patients who required revision surgery. A retrospective analysis of patients undergoing SSCD surgical repair at a single institution was performed. Information on patient demographics, primary and secondary surgical approaches, surgical outcomes, and follow-up length was collected. Seventeen patients underwent 20 revision surgeries. There were eleven (65%) females and six (35%) males. Mean age of the cohorts was 50 years (range 30−68 years), and mean follow-up length was 6.8 months (range 0.1−31.1 months). Cerebrospinal fluid leak was noted in 67% of cases. The greatest postoperative symptomatic resolution was reported in oscillopsia (100%), headache (100%), and internal sound amplification (71%), while the least postoperative symptomatic resolution was reported in tinnitus (42%), aural fullness (40%), and dizziness (29%). Revision surgery can provide symptomatic improvement in select SSCD patients; however, patients should be cautioned about the possibility of less favorable outcomes than in index surgery. Revision surgeries are associated with a considerably higher rate of perioperative cerebrospinal fluid leak. [ABSTRACT FROM AUTHOR]

Objective: Improvement of the results and effectiveness of endoscopic treatment for arachnoid cysts of the middle cranial fossa (AC MCF) in children. Methods: At the Federal Center for Neurosurgery of Tyumen 65 patients with AC MCF were operated from 2012 to 2018 by endoscopic cystocisternostomy (ECCS). Patients age ranged from one month up to 17 years. Children under 3 years old were – 32 (49%). Hypertensive symptoms were in 26 (40%); delayed speech development in 20 (31%); symptomatic epilepsy in 12 (18.5%); pathology of the ocular fundus was in 5 (7.7%). Associated abnormalities were in 19 (29%). All patients underwent CT and/or MRI. In 46 (71%) patients, cysts were located on the right, in 13 (20%) on the left and 6 (9%) bilateral. The displacement of the middle structures was diagnosed in 45 (69%). According to the Galassi classification: type II was in 20 (31%), type III – in 45 (69%) patients. The average volume of AC MCF before the operation was 181±18.6 cm3. All 65 patients underwent ECCS: a miniature neuroendoscope KarlStorz – Endoskop 11576 KF/KG was used in 47 patients, and a standard rigid endoscope LOTTA, «Gaab I scope» or flexible video scope was used in 18 patients. Results: The postoperative observation period ranged from 1 year to 8 years. The volume of cysts after surgery averaged 124.8±17.2 cm3. On average, the volume of cysts decreased by 58.2±13.5 cm3. The total efficiency of ECCS in 65 patients with AC MCF reached 81.5% of cases. Relapse was noted in 14 patients (22%). The period of recurrence ranged from 1 month to 81 month. Recurrence was in 71% of children under the age of 3 years. There was a correlation between repeated interventions and age. Children under 3 years of age have the efficiency of surgical treatment at 68.8% than in children over 3 years old – 93.8% (p≤0.01). The results of surgical treatment, depending on the endoscope used, were statistically unreliable, because when using Karl Storz – Endoskop 11576 KF/KG the total efficiency was 81%, and when using LOTTA, «Gaab I scope» or a flexible video scope – 84%. Complications in the postoperative period occurred in 6 (9%) children. Conclusion: The effectiveness of ECCS in 65 children with AC MCF reached 81.5% of cases. The effectiveness of ECCS in children under 3 years of age was 68.7%, and 93.7% in children older than 3 years.

Skull-based neuroendocrine carcinomas are rare tumors with only a few case reports in literature. Here we present an unusual case of primary neuroendocrine carcinoma of the skull in 60-year-old male which was proven on surgical biopsy. The imaging features of this rare tumor along with differential diagnosis are discussed with brief review of the literature.

A 53 years-old male, diagnosed with ulcerative colitis and liver cirrhosis due to HCV infection, was hospitalized at the Gastroenterology Department for paraclinical workup, prior to inclusion on the liver transplantation waiting list. The patient was known with a gigantic arachnoid cyst and presented a transient ischemic attack one year prior, for which treatment with aspirin was initiated. Consequently, we performed a brain MRI examination, which disclosed a left-sided gigantic arachnoid cyst with mass effect, midline shift of 9 mm and subfalcine herniation. No focal neurologic deficits or signs of increased intracranial pressure were found on neurological examination. Following neurosurgical evaluation, the presence of the cyst was not deemed to be a contraindication for liver transplantation.

Increased brain size is a characteristic of the Homo erectus hypodigm compared to early fossil hominins with changes in cerebral reorganization of evolutionary importance for the genus Homo. The close spatial proximity of the temporal lobes of the brain to the cranial base, specifically, the middle cranial fossa (MCF), provides inference of temporal lobe evolution. To date, differences in MCF proportions and relative scaling in the H. erectus hypodigm compared to extant Homo sapiens is unknown. A total sample (n = 51) of cranial Computed Tomography scans (CT) from extant H. sapiens and fossil specimens attributed to African Homo ergaster and Javanese H. erectus were generated into three-dimensional (3D) virtual models with three linear metrics digitally measured on the MCF and two metrics to approximate cranial size. Reduced Major Axis (RMA) log-log regressions and resampling with permutations determined if relative MCF scaling in the fossil sample was greater than observed among extant H. sapiens. An increase or decrease in MCF proportions in the fossil sample compared to extant H. sapiens was used to determine potential changes in temporal lobe size. There were no differences in the allometric trend of relative MCF scaling with no statistically significant differences suggesting that the fossil sample were beyond the range observed for extant H. sapiens , but the effects of the small fossil sample size could not be excluded. However, relative MCF proportions showed extant H. sapiens had a larger MCF to relative to cranial size, while specimens attributed to Javanese H. erectus which had a relatively longer and wider MCF compared to African H. ergaster. These findings indicate that despite sampling limitations, the fossil sample did not show differences in allometric scaling compared to extant H. sapiens, but these specimens attributed to Javanese H. erectus and African H. ergaster share the same total cranial size but had different MCF proportions relative to cranial size. The paleoneurological implications are that these specimens attributed to Javanese H. erectus had longer and wider temporal lobes relative to total brain size compared to African H. ergaster suggesting different patterns of cerebrocranial organization within the Homo erectus hypodigm. [ABSTRACT FROM AUTHOR]

Objective: To investigate the accuracy in localization of the anterosuperior margin of TSSJ by using the intersection point between the squamosal and parietomastoid sutures (A point) and the intersection of the squamosal suture and supramastoid crest (B point) as bony landmarks. Materials and Methods: The A and B points were marked on the inner surface of a skull by using the transillumination technique. The anatomical relationship between the projected A point, B point, and groove of TSSJ was investigated in 60 dried Thai human skulls (120 sides). Results: Of the 120 sides, the projected A points were located exactly on the anterosuperior margin of the TSSJ in 38 (31.7%) instances and adjacent (above and below) the anterosuperior margin in 82 (68.3%) cases. Of the 118 sides with identifiable supramastoid crests, the projected B points were located precisely on the anterosuperior margin of TSSJ in 60 (50.8%) cases and above the anterosuperior margin of the TSSJ in 57 (48.3%) cases. Hence, the projected B point was a more reliable bony landmark for localizing the anterosuperior margin of the TSSJ when compared with the projected A point (p = 0.003, OR 2.2, and 95% CI =1.3-3.8). Conclusion: The B point is a more reliable temporal bone landmark for localization of the TSSJ than the A point. In temporal craniotomy, an initial burr hole at the B point is relatively safe and carries a very low risk of inadvertent venous sinus injury. [ABSTRACT FROM AUTHOR]

Objective: Arachnoid cysts (ACs) are frequent incidental findings and may be associated with neuropsychiatric symptoms. Usually growth of the ACs with pressure on adjacent brain tissue is regarded as cause of the symptoms. This study was undertaken to identify if and which ACs grow with time. Methods: We used a large database of cranial MRIs for a retrospective analysis. Results: During a period of 10 years, we collected 166 ACs of 50 persons, mean observational period was 2.5 years. Among these, only larger cysts at the temporal pole, i.e., Galassi II ACs, grew with a rate of 0.3 ml a year (β = 0.32, SE 0.07, p = 0.003); all other ACs remained constant in size or became smaller. All cysts were clinically silent. Conclusions: Most ACs remain constant in size or become smaller. Classification of evidence: This study provides Class III evidence that the majority of arachnoid cysts does not grow. [ABSTRACT FROM AUTHOR]

Background: The foramen spinosum (FS) transmits the middle meningeal vessels and meningeal branches of the mandibular nerve. The anatomical variation of FS is of great clinical significance in tumor detection and abnormal bony growth. This study aimed to assess morphometric measurements of the foramen spinosum and its variation in shape, number, and position to the sphenoid spine. Methods and materials: An anatomical study was conducted on 64 adult skulls. The study material involved human macerated Ethiopian skulls. Using a screw-adjusted compass and Vernier calipers, all measurements were taken. The area of the foramen spinosum was determined using formula A= (π x L x B)/4[π = 3.14, L = length, B = width]. The mean (±SD) was calculated for all the measurements. SPSS version 20 software was used to analyze the data, and P

Introduction: The aim of present study was to undertake detailed analysis of variations in morphology of orbito-meningeal foramen (OMF), a clinically relevant entity due to possible association with major arterial branches. Materials & methods: The study was conducted on 70 bony orbits of 35 dry adult human skulls. Precise identification of OMF's were ensured and other known bony canals in the orbit were excluded. All observations and measurements were undertaken by two observers independently to reduce chances of error. Results: Overall incidence of OMF was 71.24% (left side 76% and right side 68%) and were present as single entity in orbit in most cases (80.56%) with multiplicity noted. The OMF's in present study were classified according to three parameters: size of lumen (large/medium/small), termination of canal in cranial fossa (M-Type/A -Type/ND Type) and bony component of orbit where it was located (frontal/sphenoid/fronto-sphenoid suture). Variations were noted regarding the morphology of OMF across all the three parameters in comparison to published literature. Most of the large OMF (80%) were of M-Type (opened in the middle cranial fossa). M-Type of OMF were single entities in 78.26% cases and were distributed proportionately across all three bony components of orbit. Conclusion: Based on analysis of findings it is suggested that presence of solitary OMF with large (>0.3 mm) lumen in any of the three bony components of orbit is mostly M-Type and has a high possibility of a major arterial branch passing through it. Findings could be useful towards pre-operative workup before orbital surgeries. Knowledge regarding the variations in morphological details of OMF may reduce the risk of inadvertent vascular injury in orbital region.