Skull Base Research Articles

Observations from the first 100 cases of intraoperative MRI – experiences, trends and short-term outcomes

BackgroundWe sought to analyze, in well-defined clinical setting, the first 100 patients treated at the intraoperative MRI (iMRI) hybrid surgical theatre at our facility in a population-based setting to evaluate which pathologies are best approached with iMRI assisted surgeries, as this is not yet clearly defined.MethodsPatients undergoing surgery in the 3T iMRI hybrid surgical theatre at our neurosurgical department between December 2017 to May 2021 were included after informed consent. Demographic, clinical, surgical, histological, radiological and outcome parameters, as well as variables related to iMRI, were retrospectively collected and analyzed. Patients were subdivided into adult and pediatric cohorts.ResultsVarious neurosurgical procedures were performed; resection of tumors and epileptic foci, endoscopic skull base procedures including pituitary lesions, deep brain stimulation (DBS) and laser interstitial thermal therapy (LITT). In total, 41 patients were pediatric. An iMRI scan was carried out in 96% of cases and led to continuation of surgery in 50% of cases, mainly due to visualized remaining pathological tissue (95.2%). Median time to iMRI from intubation was 280 min and median total duration of surgery was 445 min. The majority of patients experienced no postoperative complications (70%), 13 patients suffered permanent postoperative deficits, predominantly visual.ConclusionHerein, we demonstrate the first 100 patients undergoing neurosurgery aided by iMRI at our facility since introduction. Indications for surgery differed between pediatric and adult patients. The iMRI was utilized for tumor surgeries, particularly adult low-grade gliomas and pediatric tumors, as well as for epilepsy surgery and DBS. In this heterogenous population, iMRI led to continuation of surgery in 50%. To establish the benefit in maximizing the extent of resection in these brain pathologies future studies are recommended.Clinical trial numberNot applicable.

A Potential Role for Nivolumab in the Treatment of Fibrous Dysplasia-Related Pain

Abstract Fibrous dysplasia (FD) is a chronic and progressive disorder of bone growth because of decreased osteoblast formation and osteoclast overactivity. Its main symptoms include pain, fracture, and irregular bone growth. Bisphosphonates are the mainstay of therapy for FD with a primary goal of pain relief. A 50-year-old woman presented to ophthalmology in March 2011 with intermittent proptosis, vertical diplopia, and orbital pain. A computed tomography scan of the head revealed a skull base lesion, which was confirmed to be fibrous dysplasia on bone biopsy. Because of significant headache, she was treated with IV pamidronate monthly starting November 2011, which led to pain reduction. Repeated attempts to decrease the frequency of pamidronate were unsuccessful because of breakthrough pain. Oral alendronate and risedronate did not control her symptoms. She remained on risedronate however because of its convenience. In August 2021, she was diagnosed with metastatic melanoma and started nivolumab. Her headache completely resolved for the first time in 10 years. Although nivolumab, a programmed death-1 blocker, has been used in the treatment of bone malignancy, it has not been previously studied in FD. By suppressing RANK ligand-related osteoclastogenesis, nivolumab decreases cancer-associated bone pain. Our case suggests a potential role for nivolumab in treating FD-associated pain.

Giant Cell Tumor of the Central Skull Base

Giant Cell Tumor of the Central Skull Base

Intraoperative Incidental Internal Carotid Artery Injury in Extended Endoscopic Endonasal Approaches—Causes, Prevention, and Management: A Technical Note

AbstractIn spite of good anatomical awareness, the position of internal carotid artery (ICA) can be tricky in an intraoperative setup with disease causing very significant distortion of anatomy and shift of carotid artery and its branches. A 45-year-old gentleman presented with complaints of left hemicranial headache and painless progressive vision loss in both eyes (left more than right) for 8 months. A probable clinico-radiological diagnosis of meningioma was reached. Intraoperatively, bleeding occurred from left side ICA, control of which was achieved using a long gauze piece used as conventional nasal pack with crushed muscle beneath the gauze piece along with abdominal fat, which was further reinforced with Surgicel. The parasellar ICA is the most common segment injured. Dehiscent or bulging canal of ICA, presence of pseudoaneurysm, attachment of sphenoid septae to the canal, displacement by the lesion, nonenlarged sella because of small size of lesion or vertically oriented lesions, and vessel wall abnormalities increase the risk of injury. It is very essential to have a preoperative discussion involving the skull base surgeons (neurosurgeons and otorhinolaryngologists), neuroradiologists, and neuroanesthetists regarding the complications expected in the case. In case of ICA bleed, the target should be to achieve a temporary hemostasis. In small tears, cottonoids for pressure and bipolar for cauterization will help stop the bleeding, while in larger tears, giving moderate pressure using crushed muscle and cottonoids to achieve intra-operative hemostasis should be tried. After intraoperative hemostasis, the patient needs to be shifted to angiography suite for endovascular stent placement.

Acute peritumoral brainstem hemorrhage of a clival chondrosarcoma successfully treated via endoscopic endonasal surgery: illustrative case.

Chondrosarcoma is typically a slow-growing tumor, and intratumoral hemorrhage is rare. Acute brainstem hemorrhage due to chondrosarcoma has rarely been reported. A 77-year-old man presented with the sudden onset of headache and vomiting followed by a declining level of consciousness, progressive right hemiparesis, and left ophthalmoplegia. Magnetic resonance imaging showed pontine hemorrhage and a mass in the retroclival space compressing the brainstem. Emergency endoscopic endonasal surgery was performed. Intraoperative observation revealed that a hematoma was located in the pons and subdural space around the tumor mass, suggesting that the hematoma had likely been caused by the rupture of small vessels around the pons, not by intratumoral hemorrhage. The pathological diagnosis was chondrosarcoma. The patient recovered well and underwent radiotherapy. This report describes a case of sudden neurological deterioration due to hemorrhage in a patient with chondrosarcoma of the skull base. An emergency endoscopic endonasal approach for mass reduction and hematoma removal was effective in the acute setting. This approach revealed the suspected etiology of peritumoral hemorrhage, not intratumoral hemorrhage. https://thejns.org/doi/10.3171/CASE2460.

Analysis of moderate and severe traumatic brain injury associated with skull base fracture: a local tertiary center experience

BackgroundTraumatic brain injury (TBI) is a major medical and social concern in developing countries. TBI-related morbidity and mortality statistics in Egypt are lacking and do not reflect the actual magnitude of the problem.ObjectivesTo overview the incidence of moderate and severe head trauma in a heavily populated developing country and document the outcome of moderate and severe TBI associated with skull base fracture (SBF).MethodologyData of patients admitted to our center with moderate and severe TBI associated with skull base fracture (SBF) were reviewed in the period between January 2019 and March 2023.ResultsThe most common type of trauma was road traffic accidents in 54.2% of the patients; 91.2% had Single SBF (middle cranial fossa fracture was predominant 58.5%). 25.5% had an initial GCS of ≤ 8. Periorbital ecchymosis was the most common presenting sign in 36.3%. The most frequent complication (37.3%) was pneumocephalus. The presence of skull base fracture inversely affected the Glasgow outcome scale extended GOSE (P = 0.001, r = 0.674). Higher initial GCS scores were positively correlated with good GOSE (GOSE) (P = 0.001, r =− 0.222).ConclusionsRTA represents a significant cause for moderate and severe TBI in young male population. SBF is associated with poor outcome in moderate and severe TBI. Higher initial GCS score was positively correlated with good GOSE. It is important to have an overview of different types of TBI in Egypt.

A clinical prospective study on the surgical management of zygomatico-maxillary complex fractures using two-point fixation

The ZMC fractures are one of the most frequently occurring maxillofacial injuries due to its prominence and facial contour. The ZMC forms a principle buttress of face and helps transmit occlusal forces to skull base. Fracture of zygomatic bone leads aesthetic and functional deformity. Restoration to premorbid condition is most predictable by ORIF. In this study was to evaluate efficacy of two-point internal fixation using conventional miniplates and screws for ZMC fractures. 35 patients with established unilateral isolated ZMC fractures were operated using two-point fixation method i.e. the maxillary buttress and the fronto-zygomatic suture, followed up for 3 months. Patients were assessed clinically and radiographically at different follow up intervals. Charts of patients were reviewed for age, gender, etiology, malar height analysis and vertical dystopia. 35 patients in this study, underwent ORIF under GA with two-point fixation. Preoperatively, mean malar height of the patients recorded was 66.55 ± 3.02. There was a significant increase in malar height postoperatively (P < 0.0001). 70.24 ± 2.05, at 1st week, and 69.87 ± 1.98. in 3rd and 6th weeks. Preoperatively, mean vertical dystopia of patients was 2.24 ± 0.71. Postoperative resolution of vertical dystopia was statistically significant (P<0.0001), with value of 0.52 ± 0.52.Integrity of ZMC is important in maintenance of normal facial width and prominence of cheek. Two‑point fixation shows satisfactory results functionally, esthetically and also provides additional advantage by eliminating another surgical site. Thus we conclude that our study provides a basis for further research.

Endoscopic Endonasal Skull Base Surgery: Analysis of the Results in the Author’s Initial 200 Cases

Background Endoscopic endonasal approaches represent currently an important tool for approaching the skull base. The evolution of new techniques is based in the continuous acquisition of skills and abilities and it is paramount to determine the safety and effectiveness of new approaches. Based on that, the aim of this study is to analyze our results after the first 200 cases. Material and methods We performed a retrospective review of all cases operated on through an endoscopic endonasal approach in our Skull Base Unit, between January 2007 and May 2018. We analyze the results and all the per-operative complications associated. Results In this study we included 200 cases, comprising 105 female (52,2 %) and 95 male (47,5 %), with a mean age of 45,6 (range 21-85 years-old). The most commonly reported pathology was the pituitary adenoma, comprising 121 cases (60,5 %), followed by 13 meningocele (6,5 %), 9 chordoma (4,5 %), 6 skull base meningioma (3 %) and 7 cranyopharingioma (3,5 %). 161 cases (81 %) represented first surgery. The most frequently reported complication was diabetes insipidous in 17 % of all cases, followed by CSF leak, represented by 15 cases (7,5 %). 12 CSF leak cases were successfully treated by external lumbar draining and 3 patients required second surgery to skull base repair. In the last 50 cases, only one CSF leak has been reported, representing an incidence of 2 %, successfully treated by endoscopic repair. This decrease in CSF leak represents the impact of the learning curve in skull base reconstruction. 5 % of patients suffered meningitis and 5 % presented permanent anosmia. In our serie we reported 1,6 % of transient neurologic deficit represented by oculomotor palsy and 1,6 % of permanent neurologic deficit due to infarction. 3 patients in this serie has died, two due to malignant ICA occlusion and 1 due to infection (overall mortality 1,5 %). The most commonly used approach was the transsphenoidal transsellar approach (58 %), followed by transplanum-transtubercullum approach (8 %). Gross total resection was achieved in 76 % of tumoral pathology, 71 % in cases of pituitary adenomas. Conclusion From this review we can conclude that, in our serie, endoscopic endonasal surgeries represent safe approaches to the skull base to a huge variety of pathologies. Progressive acquisition of skills and experience is paramount to improve the results, avoiding and reducing complications. Appropriate patient and pathology selection is also mandatory.

Patterns of treatment failure in patients with sinonasal squamous cell carcinoma after chemoradiotherapy.

To investigate the failure patterns based on precision radiation treatment and to determine the predictive factors of treatment failure for sinonasal squamous cell carcinoma (SNSCC) patients. This was a retrospective study that included 214 cases of treatment failure from 441 consecutive patients. Two experienced radiation oncologists evaluated the tumor volume of cases with local recurrence. The 5-year overall survival (OS), progression-free survival rates (PFS), and distant-metastasis-free survival (DMFS) were estimated. Investigations were performed on the factors that predicted local failure or distant metastasis. 140 (31.7%) patients developed local recurrence, 24 (5.4%) experienced regional failure, and 65 (14.7%) underwent distant metastasis. In-field, marginal, and out-of-field failures occurred in 55.7% (78/140), 33.6% (47/140), and 10.7% (15/140) of patients with local recurrence, respectively. In logistic regression analysis, factors statistically significant for total local failure included treatment mode (p < 0.01), chemotherapy (p < 0.01), and surgical margins (p < 0.01). Primary tumors with poor differentiation (p = 0.018) and R2 resection margin (p = 0.009) were more prone to develop distant failure. The 5-year OS, PFS, and DMFS rates were 57.8%, 52.0%, and 56.7% for the whole cohort. In univariate and multivariate analysis, the skull base involvement was an independent predictor for poorer OS and PFS; orbital invasion was an independent predictor for poorer OS. Local recurrence and distant metastasis were the most common failure modes. Treatment mode, chemotherapy, and surgical margins were related to local recurrence. Poor differentiation and R2 resection margin were predictors for distant failure. Local recurrence is the most common failure pattern in patients with sinonasal squamous cell carcinoma who accepted chemoradiotherapy, and marginal and out-of-field failures occurred in 44.3% of patients with local recurrence.

B - 105 ICANS, CAR-T, and Cognition: a Case Study

Abstract Objective Immune effector cell-associated neurotoxicity syndrome (ICANS), an autoimmune delirious condition, affects 37.5% to 77% of individuals during or after chimeric antigen receptor T-cell (CAR-T) treatment for hematologic cancers (Grant et al., 2022). Initial clinical response varies widely but may include apraxia, aphasia, disorientation, and hallucinations (Möhn et al., 2022). Recent research indicates complete symptom resolution in most patients a month post-ICANS onset (Sales et al., 2023). However, a self-report study suggested more than 1 in 3 report persisting cognitive sequelae 1–5 years post-ICANS onset (Rurak et al., 2020). This discrepancy may be due to subtle changes missed by the Montreal Cognitive Objective Assessment (Sales et al., 2023; Möhn et al., 2022). The current case report investigates neurobehavioral outcome post-ICANS via comprehensive neuropsychological assessment. Method Two weeks post-CAR-T therapy, a 53-year-old male exhibited abrupt onset facial palsy and cognitive slowing prompting hospitalization. His wife reported new-onset apathy, atypical behaviors exacerbation (e.g., licking plate), and cognitive lapses (e.g., short-term memory, slowing, repeating questions) with little insight. Neuroimaging revealed supratentorial white matter hyperintensities plus calvarium and R skull base enhancing lesion regression. Results Neuropsychological assessment 10-months post-ICANS revealed subtle executive inefficiencies with family reports of improved yet ongoing social disinhibition and apathy. Conclusions This is the first comprehensive neuropsychological assessment of a patient who developed ICANS post-CAR-T therapy. Neuropsychologists should be aware of delayed cognitive sequelae possibility of this advancing treatment option. Future studies will be useful for patient/family preparation.

Muscle metastasis from cervical chordoma: a case report.

Chordomas are rare primary bone tumours that commonly occur in the sacrococcygeal and skull base region and have high rates of local recurrence. They have a locally aggressive course and the most common site of distant metastasis is the lung. The aim of this case report is to present the imaging findings of instance of muscle metastasis, a rare occurrence in cervical chordoma.

Variation of chin morphology and mandibular incisor length in different facial divergence patterns: New insights from CBCT records.

Evaluate constitutional differences in chin morphology and volume, and mandibular tooth size, between different facial divergence patterns. The sample consisted of 284 pretreatment cone beam computed tomography (CBCT) images of growing and non-growing patients who were stratified into 4 groups based on mandibular plane inclination to cranial base (SN) angle. Linear and angular measurements were made on the lateral CBCT images: mandibular lateral incisor crown (I-C) total (I-A) lengths, the distances between point D (centre of symphysis) and both incisor apex (D-A) and menton (D-Me) and between cemento-enamel junction and menton (CEJ-Me); chin width at the level of the central incisor apex (CWA) and point D (CWD); and the angles of the anterior and posterior symphyseal slopes. The volume of the symphysis was measured using a specialized 3D imaging software. Group differences and associations between parameters were gauged through the three-way ANOVA analysis. I-C, I-A, D-A, D-Me and CEJ-Me were greater in the hyperdivergent group (p < .001). CWA and CWD were wider in the hypodivergent group (p = .003). Volume of the chin and inter-slope angles were similar in all groups (p > .05). The anterior slope angle decreased with hyperdivegence (p < .005) in opposite pattern to the posterior slope angle (p < .005). Shape differences in mandibular symphysis were observed between opposite divergence patterns. Mandibular incisors were longer with hyperdivergence and shorter with hypodivergence. However, chin volumes were similar across divergence groups. These findings underline the role of genetic and environmental factors that impact facial growth.

Outcomes of Endoscopic Endonasal Surgery for Tuberculum Sellae and Planum Sphenoidale Meningiomas: A Retrospective Study.

To evaluate clinical outcomes and volumetric changes following endoscopic endonasal approach (EEA) for tuberculum sellae (TS) and planum sphenoidale (PS) meningiomas. Key objectives included evaluating pre- and postoperative tumor volumes, visual assessments and EEA-related complications. A single-center retrospective study was conducted at Foothills Medical Centre, University of Calgary, Canada, from 2009 to 2022 including 24 patients meeting inclusion criteria for midline skull base tumors, confirmed as WHO Grade I or II meningiomas with optic canal extension. EEA achieved gross total resection in 87.5% of cases, with a mean tumor volume reduction of 92.24%. Postoperatively, 91.67% exhibited visual improvement or stability. Cerebrospinal fluid leaks occurred in 12.5% of cases, necessitating revision surgery in one case. Persistent postoperative endocrine dysfunction affected 4.17%. Preoperative tumor volume did not demonstrate a correlation with complications. This study delivers reproducible data for pre- and postoperative tumor volume following the EEA after TS or PS meningiomas. The EEA demonstrated favorable radiographic and clinical outcomes in TS and PS meningiomas, achieving gross total resection with minimal morbidity.

Traumatic encephalocele in the nasal cavity after 6 years of trauma: a case report

BackgroundEncephalocele refers to protrusion of the meninges and brain tissue through a skull bone defect. It results from congenital, traumatic, neoplastic, or spontaneous reasons. Traumatic encephalocele occurs because of the posttraumatic fracture of the skull bone or iatrogenic causes. The manifestations vary a lot, such as rhinorrhea, seizures, headaches, and focal neurological deficits.Case presentationA 20-year-old Syrian male presented to our department with the complaint of clear cerebrospinal fluid drainage from his right nostril, which started 6 years ago after a head trauma, moderate headache, and episodes of tonic–clonic seizures without any response to medical treatment. Then, 2 months ago, the patient had meningoencephalitis, so he was admitted to the intensive care unit and treated for a month until he was cured. The patient underwent radiological investigations, which showed that he had a base fracture with an encephalocele in the nasal cavity. The brain tissues with the meninges herniated through the skull base fracture with a significant expansion of the subarachnoid spaces in the right hemisphere. He was advised to undergo surgical repair at that time, but he refused the surgery. During this visit, surgery was indicated. The surgery was done by a specialist who returned the herniated brain tissues to their normal location, repaired the meninges, and reconstructed the skull base with bone cement and bio-glue. The patient’s recovery after the surgery was uneventful.ConclusionTraumatic encephalocele is a rare and unexpected complication of trauma, but we should keep it in mind when the patient comes with head trauma because of its life-threatening consequences. This complication can happen after years of trauma if the patient refuses treatment, therefore, we must educate patients about the dangerous results of neglecting cerebrospinal fluid leakage and skull fractures.

A comparative study of the efficacy of customized titanium plates versus conventional maxillary protraction in the treatment of skeletal class Ⅲ patients

Objective: To compare the clinical efficacy of customized titanium plate and conventional maxillary protraction treatment in patients with skeletal class Ⅲ malocclusion during growth spurt. Methods: During growth spurt, skeletal class Ⅲ patients with maxillary hypoplasia who were treated in the Department of Orthodontics, Capital Medical University School of Stomatology from August 2018 to July 2021 were prospectively enrolled. They were treated with maxillary protraction using customized titanium plates (customized titanium plate group) and conventional methods (conventional protraction group), respectively. Lateral cephalometric radiographs were collected before and after treatment for conventional cephalometric analysis, including SNA angle (angle between Sella, Nasion and A point), ANB angle (angle between A point, Nasion, and B point), FH-MP angle (mandibular plane angle), Y-axis angle, U1-L1 angle (upper to lower central incisor angle), U1-SN angle (upper incisor to SN plane angle), anterior and lower height, maxillary length, etc. The stable basicranial line (SBL) was used as the reference line to measure the distance from each reference point (ANS point, A point, Prn point, Sn point, UL point etc.) to the stable basicranial vertical line (VerT, the perpendicular line of the skull base line at the intersection point of the anterior wall of the sella image and the inferior edge of the anterior bed process). Paired t-tests were performed on the cephalometric data before and after maxillary protraction treatment in the two groups, and two independent samples t-tests were performed to compare the differences in the efficacy of the two maxillary protraction methods. Results: A total of 20 patients (9 males and 11 females), aged (10.8±1.3) years, were included in the personalized titanium plate group. A total of 20 patients (8 males and 12 females), aged (10.5±1.1) years, were included in the conventional protraction group. The SNA angle, ANB angle, FH-MP angle, Y-axis angle, anterior lower height, maxillary length, ANS-VerT distance, A-VerT distance, Prn-VerT distance, Sn-VerT distance, and UL-VerT distance were significantly higher than those before treatment in the two groups (P<0.05). The changes of SNA angle, ANB angle and A-VerT before and after treatment in the personalized titanium plate group [3.15°±2.28°, 4.64°±1.40°, (4.41±3.43) mm, respectively] were significantly higher than those in the traditional group [2.13°±2.69°, 2.81°±1.10°, (3.13±4.76) mm, respectively](P<0.05), and the changes of U1-L1 angle and U1-SN angle before and after treatment (-0.76°±7.42° and 1.74°±6.38°, respectively) was significantly lower than that of the control group (-5.14°±6.62° and 4.57°±5.24°, respectively, P<0.05). Conclusions: Maxillary protraction can effectively improve skeletal class Ⅲ relationships in growing patients. The linear measurements using the SBL line as a reference plane visualize the sagittal improvement in sagittal relationship after maxillary protraction. The customized titanium plate maxillary protraction treatment has a clear therapeutic effect on patients with skeletal class Ⅲ deformities, and its dental effect is relatively small.

Occipital condyle syndrome due to small-cell lung carcinoma: A case report.

Skull base metastases, including those from small-cell lung carcinoma (SCLC), can present with various syndromes depending on the site of involvement, such as orbital syndrome, parasellar syndrome, middle fossa syndrome, jugular foramen syndrome, and occipital condyle syndrome (OCS). One such example is OCS, which consists of unilateral occipital headache accompanied with ipsilateral hypoglossal palsy. This case report describes a 51-year-old man initially diagnosed with OCS, which led to the discovery of systemic bone metastases from SCLC. Magnetic resonance imaging showed lesions in the occipital condyle and hypoglossal canal, while positron emission tomography-computed tomography identified a lung mass and widespread metastases. SCLC is highly aggressive and metastatic, with the bone being a common site of spread. In this case, the OCS preceded the diagnosis of the underlying malignancy. Prompt diagnosis and treatment are crucial, as patients with OCS often have advanced disease. This case highlights the importance of considering SCLC as a potential etiology for OCS, given the propensity for bone metastases. Early recognition and evaluation of OCS is essential to initiate appropriate management.

Contemporary Trends in Frontal Sinus Balloon Sinuplasty: A Pilot Study

Introduction Balloon sinuplasty (BSP) is a common treatment modality used in the management of chronic rhinosinusitis (CRS). Although it has gained popularity, minimal self-reported data on its utilization and complications have been reported. The goal of this study was to describe current practices and complications experienced during frontal sinus BSP. Methods An anonymous 20-question online survey was distributed to members of the American Osteopathic Colleges of Ophthalmology and Otolaryngology-Head and Neck Surgery from August 1, 2022, to August 30, 2022. The questions were listed as multiple choice or percentage sliding bars, and data were collected using a commercial online survey service site. Results were reported as frequencies, means, and percentages. Results Forty-two respondents participated in the survey, with the majority practicing in the following hospital settings: community (34, 80.95%), hybrid (5, 11.90%), and academic (3, 7.14%). The southeast had the largest proportion of respondents (13, 30.95%), versus the midwest (12, 28.57%), southwest (10, 23.81%), northeast (5, 11.90%), and northwest (2, 4.76%). On average, 50.52% of cases were performed in the hospital setting, 48.50% in-office, and 42.40% in surgery centers. Respondents who primarily used BSP, reported a yearly average of 35.72 cases, a median of 12 cases, and a range of 0-361 cases. Respondents who used BSP with functional endoscopic sinus surgery (FESS), reported a yearly average of 48.62 cases, a median of 31 cases, and a range of 0-189 cases. Nasal packing was utilized both intraoperatively (11.72%) and postoperatively (3.62%). Early complications included postoperative headaches (9.86%), acute bacterial sinusitis (ABRS) (3.52%), and tooth/facial numbness (0.86%). Reported long-term complications included postoperative synechiae (5.10%), orbital complications (0.14%), and skull base complications (0.10%). A previously unreported complication was identified through this study, accidental sphenopalatine fossa dilation. Conclusions This study contributes to the growing body of literature on frontal sinus BSP by characterizing utilization and complications from a large otolaryngologic academy.

Endoscopic Integrated Multipoint Laser System to Perform Quantitative Measurements for Anterior Skull Base Defects.

Measurements in endoscopic sinus surgery (ESS) are usually obtained with variable accuracy. We aimed to validate endoscopic multipoint integrated laser systems (EIMLS) for use in ESS, which can acquire measurements within one-hundredth of a millimetre. A 4.4 mm flexible endoscopic EIMLS projecting 49 laser points into the view was used to assess simulated anterior skullbase defects. Antero-posterior and lateral measurements were obtained and repeated 20 times by two surgeons. These were compared to measurements with surgical callipers. Intra and inter-observer reliability was assessed. Eighty measurements were obtained of simulated skullbase defects by each otolaryngology surgeon and compared to manual measurements. The mean difference shown was 0.56 cm. Bland-Altman plot shows low bias (0.044) but wide 95% limits of agreement (-1.8-1.9). EIMLS allows reliable and easy to obtain measurements within a simulated ESS environment. Translation of this technology offers promise in a future clinical setting but will require further refinement to improve accuracy.

Peculiarities of cerebral blood flow and vascular reactivity in patients with large and giant tumors of the cerebello-pontine angle

Background. Vestibular schwannomas and posterior fossa meningiomas are one of the most difficult tumors for surgical treatment. The mortality rate after their removal reaches 13,5 %. The main causes of death are hemorrhagic and ischemic complications. There are no studies in the literature on tissue perfusion of brainstem structures and cerebellum and reactivity of vertebral and basilar arteries in patients with extraaxial tumors of the posterior cranial fossa. Therefore, the study of the blood supply of the brainstem structures and cerebellum, as well as the functional characteristics of the vertebral and basilar arteries in these patients is of considerable interest.Aim. To evaluate tissue perfusion of the pons and cerebellum, as well asthe reactivity of the vertebral and basilar arteries in patients with large and giant vestibular schwannomas and posterior fossa meningiomas.Materials and methods. Eighty-two patients with large and giant extraaxial tumors of the base of the posterior cranial fossa were examined. The median age was 54 [44; 61] years. Vestibular schwannomas were diagnosed in 52.4 % of patients, and meningiomas of the posterior cranial fossa were diagnosed in 47.6 %. All patients underwent duplex scanning of the basilar and vertebral arteries. We evaluated linear blood flow and coefficients of reactivity and index of vasomotor reactivity. We investigated the metabolic reactivity of cerebral blood flow by conducting hyper- and hypocapnic tests. Computed tomography perfusion imaging was performed in 18 patients. We detected cerebral blood volume, cerebral blood flow, mean transit time of contrast agent and time to peak of contrast agent. Measurements were carried out in six regions of interest located symmetrically on the pons and in the white matter of the cerebellar hemispheres on the side of the tumor and on the opposite side.Results. Linear blood flow rates in the intracranial segments of the vertebral and the basilar arteries in patients with tumors were higher than in the comparison group (p&lt;0.05). These patients are characterized by a decrease of reactivity coefficients in the vertebral and basilar arteries, especially when performing hypercapnic tests (p &lt;0.05). Paradoxical reactivity and areactivity were diagnosed in 34.9 % of patients with vestibularschwannomas and 25.6 % with meningiomas. In the pons on the side of the tumor in patients with vestibularschwannomas, a decrease in cerebral blood flow by 19.3 %, an increase in cerebral blood volume by 33.3 % and an increase in mean transit time of contrast agent and in time to peak of contrast agent by 48.1 % and 71.1 % (p &lt;0.05) were found. In patients with meningiomas in the pons on the side of the tumor, all perfusion parameters were higher (p&lt;0.05). In the deep regions of the cerebellar hemisphere on the side of the tumor in patients with tumors, all perfusion parameters were higher compared to the opposite side.Conclusion. The results of the study made it possible to quantify cerebral blood flow in patients with large and giant vestibular schwannomas and meningiomas of the posterior cranial fossa base. The revealed changes indicate the risk of developing pathological vascular reactions and disorders of cerebral blood flow in the postoperative period.

Hyperostosis in meningioma: a retrospective exploration of histological correlates

Purpose Meningiomas are the most common type of primary brain tumour. Hyperostosis is commonly associated but remains incompletely understood. This study aimed to evaluate the relationship between meningioma-associated hyperostosis and other tumour variables. Materials and Methods We retrospectively analysed 245 patients with 263 cranial meningiomas (202 CNS WHO grade 1, 53 grade 2, and 8 grade 3) who underwent surgery over a three-year period. Meningiomas adjacent to the skull were included. Demographic, radiological, and tumour characteristics were analysed using standard statistical methods. Results Hyperostosis was evident in 99 (38%) of meningiomas. The most common subtypes were meningothelial, transitional, fibrous, atypical, and anaplastic. There were no statistically significant relationships between hyperostosis and bone invasion, and CNS WHO grade and histological subtype. Hyperostosis was more common in skull base meningiomas than in convexity meningiomas (p = 0.001). Ki-67 index was significantly related to CNS WHO grade but not histological subtype when grade was considered. Mean Ki-67 index was higher in meningiomas without hyperostosis (p = 0.03). There was no such relationship with bone invasion (p = 0.29). Univariate and multivariate analysis revealed that Ki-67 index was negatively correlated with hyperostosis (p = 0.03), while bone invasion (p < 0.001) and skull base location (p = 0.03) were positively correlated with hyperostosis. Conclusions Hyperostosis did not appear to be related to CNS WHO grade or histological subtype. Proliferative activity appeared to be higher in meningiomas without hyperostosis and hyperostosis was associated with evidence of bone invasion and skull base location.