Primary Middle Ear Meningioma with Intact Tympanic Membrane: A Case Report and Literature Review

Primary ectopic meningioma of the middle ear is relatively rare in clinical practice. It is often difficult to distinguish it from chronic otitis media or otitis media with effusion due to its similar and atypical clinical symptoms. We report a case of epithelial tympanic ectopic meningioma with the main complaints of otalgia, aural fullness, and hearing loss. It was accidentally discovered during tympanotomy due to the symptoms of recurring refractory secretory otitis media. This article briefly reviews the relevant literature in recent years, summarizes the characteristics of primary ectopic tympanic meningioma with intact tympanic membrane, and emphasizes the diagnosis and treatment strategy of the middle ear mass.

Does Adjuvant Gamma Knife Stereotactic Radiosurgery Have a Role in Treating Optic Nerve Sheath Meningiomas?

BACKGROUND

Meningiomas arising from or adjacent to the optic nerve sheath meningioma (ONSM) are management challenges because of their risk of visual loss. Stereotactic radiosurgery (SRS) is a minimally invasive modality that can be added as adjuvant treatment for patients whose tumor has progressed or recurred after initial resection.

METHODS

The authors retrospectively reviewed 2,030 meningioma patients who underwent SRS between 1987 and 2022. In total, 7 patients (4 females; median age = 49) were found with tumors originating from the optic nerve sheath. None of the patients had tumors that engulfed the optic nerve as such tumors typically undergo fractionated radiation therapy (FRT) to preserve vision. The clinical history, visual function, and radiographic and neurological findings were characterized. Outcome measures included visual status, tumor control, and the need for additional management.

RESULTS

All patients underwent either initial gross total (n = 1) or partial surgical resection (n = 6) before SRS. Two patients with progressive tumor growth also had SRS after failing additional fractionated radiation after surgery (54 Gy, 30 fractions for both patients). The median time between the date of surgery and the SRS procedure date was 38 months. The Leksell Gamma Knife was used to deliver a margin dose of 12 Gy (range: 8-14 Gy) to a median cumulative tumor volume of 3.3 cc (range: 1.2-18 cc). The median maximal optic nerve radiation dose was 6.5 Gy (range: 1.9-8.1 Gy). After SRS, the median follow-up time was 130 months (range: 26-169 months). Two patients showed local tumor progression at 20 and 55 months after SRS. Four had stable visual function, 2 experienced improved visual acuity, and 1 patient had visual deterioration.

CONCLUSIONS

Meningiomas arising from (but not engulfing the optic nerve) represent management quandaries after failed initial surgical removal. In this experience, salvage SRS was associated with tumor control and vision preservation in 5 of 7 patients. Additional experience with this strategy may further define the role of SRS both as a salvage and primary option.

Lateral cervical approach for ventrally located upper cervical meningioma: experience of 14 cases with a narrative comparison with other surgical techniques

BACKGROUND

Upper cervical meningioma represents a large portion of intradural extramedullary tumors that occur in the cervical spinal canal. Most of them are located ventrally or ventrolateral to the spinal cord. Reaching lesions at this location surgically is technically challenging.

OBJECTIVES

The ideal approach to ventrally located upper cervical lesions continues to be controversial. The aim of this study was to discuss the advantage of the lateral cervical approach and compare it with other surgical routes.

METHODS

This retrospective study was conducted on all cases of ventrally located upper cervical meningiomas (C1-C3) who have been operated on using the lateral cervical approach in a tertiary neurosurgery unit between 2006 and 2020. Demographic, clinical, surgical, and follow-up data were collected from hospital records.

RESULTS

During the study period, fourteen patients (Nine females and five males, aged 42-73 years) were recruited. The follow-up period was 2-16 years. The most frequent presenting symptoms were neck pain, occipital headache, motor deficits, and sensory disturbances. Total excision was achieved in all patients. All patients who had preoperative motor deficits improved significantly postoperatively, and those who presented with sensory disturbance had partial recovery. There was neither mortality nor permanent neurological morbidity.

CONCLUSION

A lateral cervical approach is a safe approach for ventrally located upper cervical lesions. In our series, it offered enough exposure for a safe dissection and total or extensive subtotal removal of the tumors. Retraction or rotation of the neuroaxis was avoided, and the incidence of complications (injury of neural or vascular structures, instability, infection) was very low.

Ki-67 index as a predictive marker of meningioma recurrence following surgical resection

BACKGROUND

Meningiomas are the most common primary intracranial tumors in adults. Although benign in a majority of cases, they have a variable clinical course and may recur even after a thorough surgical resection. Ki-67, a nuclear protein involved in cell cycle regulation, has been widely studied as a marker of cellular proliferation in various cancers. However, the prognostic significance of Ki-67 in meningiomas remains controversial. Here, we investigate the Ki-67 index, as a predictive marker of meningioma recurrence following surgical resection and compare it to established prognostic markers such as WHO grade and degree of resection.

METHODS

The medical records of 451 patients with previously untreated cranial meningiomas who underwent resections from January 2011 to January 2021 at North Shore University Hospital (NSUH) were reviewed. Collected data included WHO grade, Ki-67 proliferative index, degree of resection - gross (GTR) vs subtotal (STR) - as judged by the surgeon, tumor location, and meningioma recurrence. This study was approved by the NSUH Institutional Review Board IRB 21-1107.

RESULTS

There were 290 patients with grade I, 154 with grade II, and 7 with grade III meningiomas. The average post-resection follow-up period was 4 years, and 82 tumors (18 %) recurred. Higher WHO grades were associated with higher rates of recurrence, with rates of 11.4 %, 27.9 %, and 71.4 % for grades 1, 2, and 3, respectively, and subtotal resection corresponded to a higher rate of recurrence than total resection (34.3 % and 13.4 %, respectively). Higher WHO grades also correlated with higher Ki-67 scores (2.59, 10.01, and 20.71) for grades 1, 2, and 3, respectively. A multivariate logistic regression model identified Ki-67 and degree of resection as independent predictive variables for meningioma recurrence, with Ki-67 specifically predicting recurrence in the WHO grade II subset when analyzed separately for WHO grades I and II.

CONCLUSION

Our 10-year retrospective study suggests that the Ki-67 index is an important predictive marker for recurrence of intracranial meningiomas following surgical resection, particularly among patients with WHO grade II tumors. Our findings add to a growing body of data that support inclusion of Ki-67 index in the WHO grading criteria for patients with meningiomas.

Incidental Metaplastic Primary Pulmonary Meningioma

Primary pulmonary meningioma is a rare benign tumor usually presenting as a solitary pulmonary nodule or mass. It can be easily misinterpreted as a primary lung tumor or metastases on imaging studies. We present a 54-year-old woman with an incidentally discovered solitary lung nodule, which was diagnosed as metaplastic primary pulmonary meningioma following resection. Metaplastic meningioma is a rare WHO grade 1 meningioma subtype with focal or global mesenchymal differentiation. To the authors' knowledge, primary pulmonary meningioma with mesenchymal differentiation has not been described previously in the English literature.

Predictors of salvage therapy for parasagittal meningiomas treated with primary surgery, radiosurgery, or surgery plus adjuvant radiotherapy

OBJECTIVE

Parasagittal meningiomas (PM) are treated with primary microsurgery, radiosurgery (SRS), or surgery with adjuvant radiation. We investigated predictors of tumor progression requiring salvage surgery or radiation treatment. We sought to determine whether primary treatment modality, or radiologic, histologic, and clinical variables were associated with tumor progression requiring salvage treatment.

METHODS

Retrospective study of 109 consecutive patients with PMs treated with primary surgery, radiation (RT), or surgery plus adjuvant RT (2000-2017) and minimum 5 years follow-up. Patient, radiologic, histologic, and treatment data were analyzed using standard statistical methods.

RESULTS

Median follow up was 8.5 years. Primary treatment for PM was surgery in 76 patients, radiation in 16 patients, and surgery plus adjuvant radiation in 17 patients. Forty percent of parasagittal meningiomas in our cohort required some form of salvage treatment. On univariate analysis, brain invasion (OR: 6.93, p < 0.01), WHO grade 2/3 (OR: 4.54, p < 0.01), peritumoral edema (OR: 2.81, p = 0.01), sagittal sinus invasion (OR: 6.36, p < 0.01), sagittal sinus occlusion (OR: 4.86, p < 0.01), and non-spherical shape (OR: 3.89, p < 0.01) were significantly associated with receiving salvage treatment. On multivariate analysis, superior sagittal sinus invasion (OR: 8.22, p = 0.01) and WHO grade 2&3 (OR: 7.58, p < 0.01) were independently associated with receiving salvage treatment. There was no difference in time to salvage therapy (p = 0.11) or time to progression (p = 0.43) between patients receiving primary surgery alone, RT alone, or surgery plus adjuvant RT. Patients who had initial surgery were more likely to have peritumoral edema on preoperative imaging (p = 0.01). Median tumor volume was 19.0 cm3 in patients receiving primary surgery, 5.3 cm3 for RT, and 24.4 cm3 for surgery plus adjuvant RT (p < 0.01).

CONCLUSION

Superior sagittal sinus invasion and WHO grade 2/3 are independently associated with PM progression requiring salvage therapy regardless of extent of resection or primary treatment modality. Parasagittal meningiomas have a high rate of recurrence with 80.0% of patients with WHO grade 2/3 tumors with sinus invasion requiring salvage treatment whereas only 13.6% of the WHO grade 1 tumors without sinus invasion required salvage treatment. This information is useful when counseling patients about disease management and setting expectations.

Middle third falcine meningiomas-surgical nuances for cortical venous preservation

PURPOSE

To improve postoperative outcome in middle third falcine meningiomas by cortical venous preservation.

BACKGROUND

Falcine meningiomas arise from the falx and do not involve the superior sagittal sinus (SSS). Their complete resection is often associated with the risk of venous infarction in the eloquent cortex due to overlying superficial cortical veins on the tumors.

METHOD

We report one case of middle third falcine meningioma, where we used the posterior interhemispheric corridor for tumor approach.

CONCLUSION

Use of the posterior interhemispheric approach, carefully raised bone flap, along with sharp dissection and vein reinforcement using fibrin glue can help to preserve the cortical veins while resecting the falcine meningiomas.

Descriptive epidemiology of 30,223 histopathologically confirmed meningiomas in France: 2006-2015

BACKGROUND AND OBJECTIVES

Meningioma is one of the most common neoplasm of the central nervous system. To describe the epidemiology of meningioma operated in France and, to assess grading and histopathological variability among the different neurosurgical centres.

METHODS

We processed the French Brain Tumour Database (FBTDB) to conduct a nationwide population-based study of all histopathologically confirmed meningiomas between 2006 and 2015.

RESULTS

30,223 meningiomas cases were operated on 28,424 patients, in 61 centres. The average number of meningioma operated per year in France was 3,022 (SD ± 122). Meningioma was 3 times more common in women (74.1% vs. 25.9%). The incidence of meningioma increased with age and, mean age at surgery was 58.5 ± 13.9 years. Grade 1, 2, and 3 meningiomas accounted for 83.9%, 13.91% and, 2.19% respectively. There was a significant variability of meningioma grading by institutions, especially for grade 2 which spanned from 5.1% up to 22.4% (p < 0.001). Moreover, the proportion of grade 2 significantly grew over the study period (p < 0.001). There was also a significant variation in grade 1 subtypes diagnosis among the institutions (p < 0.001). 89.05% of the patients had solely one meningioma surgery, 8.52% two and, 2.43% three or more. The number of surgeries was associated to the grade of malignancy (p < 0.001).

CONCLUSION

The incidence of meningioma surgery increased with age and, peaked at 58.5 years. They were predominantly benign with meningothelial subtype being the most common. However, there was a significant variation of grade 1 subtypes diagnosis among the centres involved. The proportion of grade 2 meningioma significantly grew over the study time, on contrary to malignant meningioma proportion, which remained rare and, stable over time around 2%. Likewise, there was a significant variability of grade 2 meningioma rate among the institutions.

Neurosurgical treatment and outcome patterns in patients with meningioma in South Moravian region-a population-based study

INTRODUCTION

Meningiomas are usually slow-growing tumours, constituting about one third of all primary intracranial tumours. They occur more frequently in women. Clinical manifestation of meningiomas depends on their location, tumour size and growth rate. In most cases, surgical treatment is the procedure of choice. The success of this treatment is, however, associated with the radicality of the resection. Radiotherapy represents an additional or alternative treatment modality. Gamma knife surgery is another notable treatment method, especially in small and/or slow-growing tumours in eloquent areas or in elderly patients.

MATERIAL AND METHODS

Authors describe their experience with the diagnosis, treatment and outcome of the patients with meningioma (n = 857). Furthermore, they also assess the postoperative morbidity/mortality and recurrence rate.

RESULTS AND CONCLUSIONS

In view of the benign histology of meningiomas, the success of the treatment largely depends (besides the tumour grading) on the radicality of the resection. The emphasis is also put on appropriate follow-up of the patients. In certain patients, the watch and wait strategy should be also considered as a suitable treatment method.

Anterior clinoid meningiomas: surgical results and proposed scoring system to predict visual outcomes

OBJECTIVE

The authors report a single-surgeon experience with anterior clinoid meningiomas (ACMs) and propose a novel scoring system to predict visual outcomes based on preoperative risk factors.

METHODS

A cohort study of all ACMs that were surgically treated by a single surgeon between 2003 and 2021 was performed. Visual function was assessed by an ophthalmologist pre- and postoperatively. Based on the combination of visual fields and visual acuity, 4 visual grades were described. Favorable visual outcomes were defined as mild visual deficit or intact vision postoperatively. Unfavorable visual outcomes were defined as a severe or moderate visual deficit. Predictors of unfavorable visual outcomes were identified using multivariable logistic regression analysis. A scoring system was then created using the resulting β coefficient. A receiver operating characteristic curve analysis was performed to identify a cutoff point on the grading score for stratifying patients at risk for unfavorable visual outcomes.

RESULTS

Fifty-two patients met all inclusion criteria. Twenty-five (48%) patients presented with intact vision, and 27 (51%) presented with some visual dysfunction. Postoperative favorable visual outcomes were achieved in 39 patients (75%). Among the 27 patients presenting with visual dysfunction, 14 (52%) experienced improvement after surgery. No new visual deficits were observed among the 25 patients with intact vision at baseline. Nine patients (17%) had a reversible complication. Multivariable analysis showed that severe preoperative visual deficit (OR 13.03, 95% CI 2.64-64.39; p = 0.002), radiographic evidence of optic nerve (ON) encasement (OR 4.20, 95% CI 1.06-16.61; p = 0.04), intraoperative evidence of ON invasion (OR 17.31, 95% CI 2.91-102.86; p = 0.002), an average ganglion cell layer thickness of ≤ 70 µm (OR 21.54, 95% CI 2.94-159.04; p = 0.003), and an average retinal nerve fiber layer thickness of ≤ 80 µm (OR 13.68, 95% CI 1.91-98.00; p = 0.009) were associated with unfavorable visual outcome. The predictive score included the following factors: abnormal optical coherence tomography (OCT) findings, radiographic evidence of ON encasement by the tumor, and severe preoperative visual deficit. A score ≥ 4 of 6 points was demonstrated to be the cutoff associated with unfavorable visual outcome, with a sensitivity of 80%, specificity of 88%, positive predictive value of 80%, negative predictive value of 88%, and area under the curve of 0.847 (95% CI 0.674-1.0; p = 0.003).

CONCLUSIONS

The authors have designed a practical and novel scoring system to predict visual outcomes in patients with ACMs. This scoring system may guide preoperative discussions with patients and timely surgical intervention to yield optimal visual function outcomes. Although most patients have excellent neurosurgical outcomes, severe baseline visual deficits, ON encasement, and characteristic OCT abnormalities are associated with unfavorable visual function after ACM resection.

Predicting histological grade in symptomatic meningioma by an objective estimation of the tumoral surface irregularity

INTRODUCTION

Predicting the histopathologic grade of meningioma is relevant because local recurrence is significantly greater in WHO grade II-III compared to WHO grade I tumours, which would ideally benefit from a more aggressive surgical strategy. It has been suggested that higher WHO grade tumours are more irregularly-shaped. However, irregularity is a subjective and observer-dependent feature. In this study, the tumour surface irregularity of a large series of meningiomas, measured upon preoperative MRI, is quantified and correlated with the WHO grade.

METHODS

Unicentric retrospective observational study of a cohort of symptomatic meningiomas surgically removed in the time period between January 2015 and December 2022. Using specific segmentation software, the Surface Factor (SF) was calculated for each meningioma. SF is an objective parameter that compares the surface of a sphere (minimum surface area for a given volume) with the same volume of the tumour against the actual surface of the tumour. This ratio varies from 0 to 1, being 1 the maximum sphericity. Since irregularly-shaped meningiomas present proportionally greater surface area, the SF tends to decrease as irregularity increases. SF was correlated with WHO grade and its predictive power was estimated with ROC curve analysis.

RESULTS

A total of 176 patients (64.7% females) were included in the study; 120 WHO grade I (71.9%), 43 WHO grade II (25.7%) and 4 WHO grade III (2.4%). A statistically significant difference was found between the mean SF of WHO grade I and WHO grade II-III tumours (0.8651 ± 0.049 versus 0.7081 ± 0.105, p < 0.0001). Globally, the SF correctly classified more than 90% of cases (area under ROC curve 0.940) with 93.3% sensibility and 80.9% specificity. A cutoff value of 0.79 yielded the maximum precision, with positive and negative predictive powers of 82.6% and 92.6%, respectively. Multivariate analysis yielded SF as an independent prognostic factor of WHO grade.

CONCLUSION

The Surface Factor is an objective and quantitative parameter that helps to identify aggressive meningiomas preoperatively. A cutoff value of 0.79 allowed differentiation between WHO grade I and WHO grade II-III with high precision.

Endovascular stenting for cerebral venous sinus stenosis secondary to meningioma invasion

INTRODUCTION

Symptomatic intracranial hypertension (IH) due to venous outflow obstruction secondary to dural venous sinus (DVS) tumoral invasion affects up to 3% of intracranial meningioma patients. The literature regarding endovascular therapies of such patients is limited to a few case reports and a recent single-centre case series.

PURPOSE

We describe our single-centre experience of endovascular therapy in patients with clinically symptomatic IH secondary to DVS meningioma invasion.

METHODS

We performed a retrospective review of clinical and radiological data of all patients with refractory IH and meningiomas invading the DVS who were referred for possible DVS venoplasty and stenting. Seven endovascular procedures in six female patients were done. Presumed secondarily induced lateral transverse sinus stenosis was also stented in four patients as part of the primary intervention.

RESULTS

All patients experienced complete symptomatic resolution at 6-month follow-up. Five patients had no symptom recurrence over a mean follow-up period of 3.5 years. One patient with multiple meningiomas developed recurrent IH 2 years following stenting secondary to in-stent tumour re-invasion. This was re-stented with consequent 6 months post-retreatment symptomatic relief at the time of writing. No procedure-related complications occurred.

CONCLUSION

In the setting of DVS stenosis secondary to meningioma invasion, endovascular therapy is a safe and successful therapeutic option with promising mid-term results. The procedure should be considered in cases where complete surgical tumour resection is unlikely or carries a significant risk. If present, secondarily induced stenoses at the lateral ends of the transverse sinuses should also be considered for treatment.

Usefulness of Opening the Diaphragma Sellae Before Transecting Interclinoidal Ligament for Endoscopic Endonasal Transoculomotor Triangle Approach: Technical Nuances and Surgical Outcomes

OBJECTIVE

Opening the oculomotor triangle (OT) and removing the posterior fossa lesion by endoscopic endonasal approach (EEA) is challenging for even an experienced endoscopic neurosurgeon. We summarize the treatment experience and technical nuances with EEA for resection of pituitary neuroendocrine tumors and cavernous sinus (CS) meningiomas invading through the OT.

METHODS

Between 2018 and 2022, 8 patients, comprising 5 with pituitary neuroendocrine tumors (3 with nonfunctioning and 2 with somatotroph tumors with increased levels of growth hormone) and 3 CS meningiomas, were treated using an endoscopic endonasal transoculomotor triangle approach. The critical surgical technique is continuously opening the diaphragma sellae from medial to lateral toward the interclinoidal ligament and transecting it to enlarge the OT. We evaluated preoperative tumor size, previous surgical history, preoperative symptoms, extent of tumor resection, histopathology, and postoperative complications for all patients.

RESULTS

The gross total resection (defined as complete removal) in 3 patients (38%), near-total resection (defined as >95% removal) in 4 patients (50%), and subtotal resection (defined as ≤90% removal) in 1 patient (12%) and gross total resection of tumor invading through the OT was achieved in all patients through pure EEA. Two of 3 patients with visual deficits in nonfunctioning pituitary neuroendocrine tumors improved, and the other remained stable postoperatively. One patient showed transient oculomotor nerve palsy. The growth hormone level of the 2 patients with somatotroph tumors declined to normal. For 3 patients with CS meningiomas, cranial nerve palsy improved in 2 patients, whereas the other patient developed increased facial numbness after surgery.

CONCLUSIONS

The endoscopic endonasal transoculomotor triangle approach is an efficient surgical option for tumors with CS invasion and OT penetration.

Prediction of Meningioma Grade Using Hematological Parameters

OBJECTIVE

Predicting the aggressiveness of meningiomas may influence the surgical strategy timing. Because of the paucity of robust markers, the systemic immune-inflammation (SII) index is a novel biomarker to be an independent predictor of poor prognosis in various cancers including gliomas. We aimed to investigate the value of SII as well as neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) indices in predicting prognosis.

METHODS

Records including demographic, clinical, and laboratory data of patients operated on due to intracranial meningioma in 2017-2023 were retrospectively reviewed.

RESULTS

A total of 234 patients were included in this study. All of SII index, NLR, and PLR values at presentation were significantly higher in grade ≥2 meningiomas. A positive correlation was observed between SII index and Ki67 index (r=0.313; P<0.001); between NLR and Ki67 index (r=0.330; P<0.001); and between PLR and Ki67 index (r=0.223; P<0.01). SII index (optimal cutoff level >618), NLR (optimal cutoff level >3.53), and PLR (optimal cutoff level >121.2) showed significant predictive values.

CONCLUSIONS

This is the first study to assess the prognostic value of the SII index in patients with intracranial meningiomas. Increased SII index, NLR and PLR were correlated with higher grade and higher Ki-67 index. They also harbor the potential to screen patients that may need more aggressive treatments or more frequent follow-up examinations.

A modern approach to olfactory groove meningiomas

OBJECTIVE

Management of olfactory groove meningiomas (OGMs) has changed significantly with the advances in extended endoscopic endonasal approaches (EEAs), which is an excellent approach for patients with anosmia since it allows early devascularization and minimizes retraction on the frontal lobes. Craniotomy is best suited for preservation of olfaction. However, not infrequently, a tumor presents after extending outside the reach of an EEA and a solely transcranial approach would require manipulation and retraction of the frontal lobes. These OGMs may best be treated by a staged EEA-craniotomy approach. In this study the authors' goal was to present their case series of patients with OGMs treated with their surgical approach algorithm.

METHODS

The authors conducted an IRB-approved, nonrandomized historic cohort including all consecutive cases of OGMs treated surgically between 2010 and 2020. Patient demographic information, presenting symptoms, operative details, and complications data were collected. Preoperative and postoperative tumor and T2/FLAIR intensity volumes were calculated using Visage Imaging software.

RESULTS

Thirty-one patients with OGMs were treated (14 craniotomy only, 11 EEA only, and 6 staged). There was a significant difference in the distribution of patients presenting with anosmia and visual disturbance by approach. Tumor size was significantly correlated with preoperative vasogenic edema. Gross-total resection was achieved in 90% of cases, with near-total resection occurring twice with EEA and once with a staged approach. T2/FLAIR hyperintensity completely resolved in 90% of cases and rates did not differ by approach. Complication rates were not significantly different by approach and included 4 CSF leaks (p = 0.68).

CONCLUSIONS

A staged approach for the management of large OGMs with associated anosmia and significant lateral extension is a safe and effective option for surgical management. Through utilization of the described algorithm, the authors achieved a high rate of GTR, and this strategy may be considered for large OGMs.

Time to Recurrence of Intracranial Meningiomas from a Monoinstitutional Surgical Series

BACKGROUND

Meningiomas show variable tendency to recur. While risk factors of recurrence have been largely investigated in literature, a paucity of data is available on the time to recurrence. Our purpose was to identify main factors affecting the time to recurrence to assist preoperative treatment decision-making strategy and to define a tailored clinical and neuroradiological follow-up.

METHODS

Data of 35 patients with intracranial meningioma recurrences have been retrospectively reviewed. Demographic (patient age at initial diagnosis and sex), radiologic (meningioma location, pattern of regrowth and topography of recurrences at first reoperation), pathologic (WHO grade and Ki67-MIB1 at initial surgery and at first reoperation, progesterone receptor [PR] expression), and surgical (extent of resection at initial surgery according to Simpsons grading system, number of reoperations) factors were analyzed.

RESULTS

Time to recurrence ranged from 20 to 120 months. Extent of resection at initial surgery was Simpson grade I in 7 patients (20%), grade II in 10 (28.5%), grade III in 14 (40%), and grade IV in 4 (11.5%). Longer median time to recurrence was observed for skull base localization (P < 0.01), Simpson grades I and II versus grades III (P = 0.01) and IV (P = 0.02), values of Ki67-MIB1 ≤ 4% (P = 0.001), and PR > 60% (P = 0.03); conversely, sex, age, number of reoperations, unchanged/progression of Ki67, and/or World Health Organization grade between first surgery and reoperation did not correlate in statistically significant way with time to recurrence.

CONCLUSIONS

The extent of resection and the Ki67-MIB1 represent the most important factors predicting shorter recurrence time of intracranial meningiomas. Patients with incomplete (Simpson grades III and IV) resection and high Ki67-MIB1 values, especially at non-skull base localization and with low PR values, require a closer short-term clinical and radiologic follow-up in the first years after surgery.

[Facial nerve protection in surgery for rare tumors of the internal auditory canal]

Objective:To explore strategies for preserving facial nerve function during surgeries for rare tumors of the internal auditory canal. Methods:A total of 235 cases of internal auditory canal tumors treated between 2010 and 2023 were included, encompassing vestibular schwannomas, cavernous hemangiomas, meningiomas, and other rare tumors. Various data, including clinical presentations, imaging classifications, and treatment processes, were meticulously analyzed to delineate the characteristics of rare tumors and assess pre-and postoperative facial nerve function. Results:Among all internal auditory canal tumors, vestibular schwannomas accounted for 91.9%. In rare tumors, facial nerve schwannomas constituted 5.3%, cavernous hemangiomas 26.3%, meningiomas 15.8%, and arterial aneurysms 10.5%. Significantly, patients with cavernous hemangiomas displayed pronounced invasion of the facial nerve by the tumor, in contrast to other tumor types where clear boundaries with the facial nerve were maintained. During surgery, individualized approaches and strategies for facial nerve protection were implemented for different tumor types, involving intraoperative dissection, tumor excision, and facial nerve reconstruction. Conclusion:Preservation of the facial nerve is crucial in the surgical management of rare tumors of the internal auditory canal. Accurate preoperative diagnosis, appropriate timing of surgery, selective surgical approaches, and meticulous intraoperative techniques can maximize the protection of facial nerve function. Personalized treatment plans and strategies for facial nerve functional reconstruction are anticipated to enhance surgical success rates, reduce the risk of postoperative facial nerve dysfunction, and ultimately improve the quality of life for patients.

Minimally invasive approach for skull base meningiomas

INTRODUCTION

Skull base meningiomas constitute a complex group of skull base tumors. The endoscopic endonasal approaches (EEA) and endoscopic Keyhole have a minimally invasive philosophy with high effectiveness, safety, and a significant decrease in postoperative morbidity in these tumors.

OBJECTIVE

To describe the results of the use of minimally invasive approaches to skull base meningiomas.

METHOD

A descriptive, retrospective study was carried out in 140 patients at the "Hermanos Ameijeiras" Hospital who underwent surgery for cranial base meningiomas using minimally invasive approaches to the cranial base. The degree of tumor resection, tumor recurrence, reinterventions, and complications were evaluated.

RESULTS

ESA were used in 72.8% of the study, while endoscopic Keyholes were used in 26.4% and combined approaches in 0.7%. In relation to total tumor resection, 91.9% was generally achieved. Overall tumor recurrence and reinterventions were less than 8.5% and 4%, respectively. Complications in ESA were: cerebrospinal fluid (CSF) fistula (2.1%), diabetes insipidus, hydrocephalus, cerebral infarction, surgical site hematoma, worsening of cranial nerves I-IV (1.4%) respectively. While in the Keyhole type approaches: seizures (2.9%), hydrocephalus (1.4%), CSF fistula (1.4%), worsening of Nerves IX-XII (0.7%).

CONCLUSIONS

The following study reaffirms that minimally invasive approaches for skull base meningiomas constitute advanced surgical techniques for these tumors, associated with a low rate of postoperative complications.

Superficial meningioma with bone involvement: surgical strategies and clinical outcomes

INTRODUCTION

Meningiomas with bone involvement account for 4.5-17% of all intracranial meningiomas. Little is known about whether these meningiomas (WHO grade I) behave differently than meningiomas without bone involvement. We sought to study the relatively uncommon imaging manifestations of meningioma and to evaluate their clinical significance.

METHODS

A single-institution retrospective cohort study of surgically treated superficial meningioma patients between 2011 and 2022 was conducted. Age, sex, preoperative imaging, operative data, and surgical outcomes were reviewed. Imaging variables and outcomes were reported for patients with bone-invading meningiomas and compared with those with nonbone-invading meningiomas. Univariate analyses were also conducted.

RESULTS

Of 577 total superficial meningiomas treated surgically, 47 (8.1%) exhibited bone invasion. Most bone-invading meningiomas were parasagittal (n = 29, 61.7%). A total of 12.7% (n = 6) of patients with bone-invading meningioma had recurrence, whereas 9.1% (n = 48) of patients with non-bone-invading meningioma had recurrence (p = 0.426). No significant difference in the median time to recurrence was observed between patients with bone-invading meningiomas and patients with nonbone-invading meningiomas (69.8 months, Q1:53.1; Q3:81.4 months vs. 69.7 months, Q1:47.5; Q3:96.7; p = 0.638).

CONCLUSIONS

Superficial meningioma with bone involvement had similar outcomes compared to those of superficial meningioma without bone involvement. Hyperostosis in meningioma (WHO grade I) may not be a surrogate for aggressive meningioma behavior.

Atypical meningiomas compared to other WHO Grade 2 meningiomas: Histological features and prognosis

OBJECTIVES

To study each atypical feature in atypical meningioma versus other grade 2 meningiomas and its possible relation to recurrence.

METHODS

This is a retrospective study of patients with WHO grade 2 meningioma operated in our institution between 01/2008 and 12/2020. The rate of recurrence, reoperation and readmission were recorded during the follow-up period. A statistical analysis was done to determine the significance of each pathological feature in regard to recurrence.

RESULTS

A total of 74 patients were included as WHO grade 2 meningioma with 60 (81%) patients having an AM and 14 (19%) patients with chordoid or clear cell meningioma. The mean age was 51 years±14. The most common location was meningioma abutting the frontal lobe (convexity). Major atypical features were more noted in the AM, however, there was no significant difference between AM and other types of meningioma. Increased Nuclear cytoplasmic ratio and cellularity were found significantly more in AM. The recurrence rate was 16.2%. No specific pathology feature (major or minor) nor the type of Grade 2 meningioma was significantly related to recurrence.

CONCLUSION

The types of WHO grade 2 meningiomas have similar prognosis and recurrence rates. There is no significant difference between the atypical features in indicating a more aggressive nature or risk of recurrence in grade 2 meningiomas.

Inflammatory pseudotumor, the great mimicker: A case report

Inflammatory pseudotumor is a rare lesion, especially at the level of the central nervous system. Its etiology is unknown and the most accepted hypothesis is that it is the consequence of an exaggerated immune response. We present the clinical case of a young Senegalese male, with a history of epilepsy secondary to severe cranioencephalic trauma in childhood, who presented with new epileptic seizures. Imaging tests showed a lesion in the anterior fossa intimately attached to the meninges, so the initial diagnosis was meningioma. A bifrontal craniotomy and microsurgical excision were performed. The definitive anatomopathological analysis concluded that the lesion is an inflammatory pseudotumor whose origin is secondary to a disproportionate reparative process after cranioencephalic trauma.

Widening the Operative Corridor-Evaluating the Transcortical Approach to Giant Falcine Meningiomas

BACKGROUND

Giant falcine meningiomas are surgically complex as they are deep in location, concealed by normal brain parenchyma, in close proximity to various neurovascular structures, and frequently involve the falx bilaterally. Although classically accessed using a bifrontal craniotomy and interhemispheric approach, little data exist on alternative operative corridors for these challenging tumors. We evaluated perioperative and long-term outcomes in patients undergoing transcortical resection of giant bilateral falcine meningiomas.

METHODS

From 2013 to 2022, fourteen patients with giant bilateral falcine meningiomas treated via a transcortical approach at our institution were identified. Perioperative and long-term outcomes were evaluated to determine predictors of adverse events. Corticectomy depth was also analyzed to determine if it correlated with increased postoperative seizure rates.

RESULTS

57.1% of cases were WHO grade 2 meningiomas. Average tumor volume was 77.8 ± 46.5 cm3 and near/gross total resection was achieved in 78.6% of patients. No patient developed a venous infarct or had seizures in the 6 months after surgery. Average corticectomy depth was 0.83 ± 0.71 cm and increasing corticectomy depth did not correlate with higher risk of postoperative seizures (P = 0.44). Increasing extent of tumor resection correlated with lower tumor grade (P = 0.011) and only 1 patient required repeat resection during a median follow-period of 24.9 months.

CONCLUSIONS

The transcortical approach is a safe alternative corridor for accessing giant, falcine meningiomas, and postoperative seizures were not found to correlate with increasing corticectomy depth. Further prospective studies are necessary to determine the best approach to these surgically complex lesions.

Orbital reconstruction and volume in the correction of proptosis after resection of spheno-orbital meningiomas

OBJECTIVE

The objective of this study was to evaluate the effect of reconstruction and orbital volume on the reduction of proptosis in patients undergoing resection for spheno-orbital meningiomas. Additionally, potential predictors of optimal proptosis reduction after surgery were evaluated.

METHODS

Patients with spheno-orbital meningiomas who underwent resection at the authors' institution between 2005 and 2020 were evaluated retrospectively. The exophthalmos index (EI) was measured on pre- and postoperative imaging to quantify proptosis and calculate the primary outcome measure of proptosis reduction. Patients were excluded if they had no preoperative proptosis (i.e., EI < 1.1), prior resection, or insufficient imaging available for analysis. Clinical and surgical characteristics were collected, including sex, extent of resection, WHO grade, and rigid orbital reconstruction, and assessed as predictors of greater proptosis reduction. Additionally, orbital volumes of the affected and contralateral orbits were measured to correlate postoperative orbital volumes with proptosis reduction.

RESULTS

Thirty-three patients, with a mean age of 53 years, met inclusion criteria. The majority of the patients were female (23, 69.7%), and most tumors were classified as WHO grade 1 (29, 87.9%). Six patients (18.2%) underwent rigid orbital reconstruction. The mean EI across all patients decreased from 1.36 ± 0.18 to 1.19 ± 0.15 (p < 0.001). Patients who underwent reconstruction had on average a 76.4% greater reduction in the EI (p = 0.036) and a 9.1 times higher odds of achieving a normal EI (< 1.1) compared with those who did not receive reconstruction (OR 9.1, p = 0.025). Additionally, patients without residual hyperostotic bone compressing the orbit had a 2.16 times greater reduction in EI (p = 0.039). A linear relationship between orbital volume ratios (affected/unaffected orbit) and proptosis reduction was observed (p = 0.029, r = 0.529), including at ratios > 1.0. This suggests that greater orbital volumes postoperatively correlated with greater reductions in proptosis.

CONCLUSIONS

Three factors were identified that optimize proptosis correction. First, all abnormal bone compressing the orbital contents must be removed completely. Second, rigid orbital reconstruction leads to improved proptosis correction, possibly by preventing frontal lobe and dural reconstruction from descending onto the compressed orbit. Third, aiming for an orbital volume slightly larger than the contralateral normal side leads to improved proptosis correction.

Novel classification of foramen magnum meningiomas predicted by topographic position relative to neurovascular bundle

PURPOSE

Proximity to critical neurovascular structures can create significant obstacles during surgical resection of foramen magnum meningiomas (FMMs) to the detriment of treatment outcomes. We propose a new classification that defines the tumor's relationship to neurovascular structures and assess correlation with postoperative outcomes.

METHODS

In this retrospective review, 41 consecutive patients underwent primary resection of FMMs through a far lateral approach. Groups defined based on tumor-neurovascular bundle configuration included Type 1, bundle ventral to tumor; Type 2a-c, bundle superior, inferior, or splayed, respectively; Type 3, bundle dorsal; and Type 4, nerves and/or vertebral artery encased by tumor.

RESULTS

The 41 patients (range 29-81 years old) had maximal tumor diameter averaging 30.1 mm (range 12.7-56 mm). Preoperatively, 17 (41%) patients had cranial nerve (CN) dysfunction, 12 (29%) had motor weakness and/or myelopathy, and 9 (22%) had sensory deficits. Tumor type was relevant to surgical outcomes: specifically, Type 4 demonstrated lower rates of gross total resection (65%) and worse immediate postoperative CN outcomes. Long-term findings showed Types 2, 3, and 4 demonstrated higher rates of permanent cranial neuropathy. Although patients with Type 4 tumors had overall higher ICU and hospital length of stay, there was no difference in tumor configuration and rates of postoperative complications or 30-day readmission.

CONCLUSION

The four main types of FMMs in this proposed classification reflected a gradual increase in surgical difficulty and worse outcomes. Further studies are warranted in larger cohorts to confirm its reliability in predicting postoperative outcomes and possibly directing management decisions.

Chronic hyperglycemia and intracranial meningiomas

Meningiomas are among the most common primary tumors of the central nervous system. Previous research into the meningioma histological appearance, genetic markers, transcriptome and epigenetic landscape has revealed that benign meningiomas significantly differ in their glucose metabolism compared to aggressive lesions. However, a correlation between the systemic glucose metabolism and the metabolism of the tumor hasn't yet been found. We hypothesized that chronic levels of glycaemia (approximated with glycated hemoglobin (HbA1c)) are different in patients with aggressive and benign meningiomas. The study encompassed 71 patients with de novo intracranial meningiomas, operated on in three European hospitals, two in Croatia and one in Spain. Our results show that patients with WHO grade 2 meningiomas had significantly higher HbA1c values compared to patients with grade 1 lesions (P = 0.0290). We also found a significant number of patients (19/71; 26.7%) being hyperglycemic, harboring all the risks that such a condition entails. Finally, we found a significant correlation between our patients' age and their preoperative HbA1c levels (P = 0.0008, ρ(rho) = 0.388), suggesting that older meningioma patients are at a higher risk of having their glycaemia severely dysregulated. These findings are especially important considering the current routine and wide-spread use of corticosteroids as anti-edematous treatment. Further research in this area could lead to better understanding of meningiomas and have immediate clinical impact.

Microsurgical resection of a large petroclival meningioma through an extended retrosigmoid approach: how I do it

BACKGROUND

Petroclival meningiomas are challenging tumors. Several skull base approaches have been proposed in the last decades, with variable rates of postoperative morbidity and extent of resection.

METHODS

We herein reported the step-by-step microsurgical resection of a large petroclival meningioma through an extended retrosigmoid approach. Detailed surgical technique has been accompanied by a 2D operative video.

CONCLUSION

The extended retrosigmoid approach allowed for a safe gross total resection of the tumor, as confirmed by the postoperative MRI. The patient did not experience any new postoperative deficit, despite a transient diplopia, and was discharged on postoperative day 7.

Plasma extracellular vesicles in meningioma patients following radiotherapy as liquid biopsy- a prospective explorative biomarker study (ARO 2023-05/AG-NRO-07)

BACKGROUND

While surgical resection remains the primary treatment approach for symptomatic or growing meningiomas, radiotherapy represents an auspicious alternative in patients with meningiomas not safely amenable to surgery. Biopsies are often omitted in light of potential postoperative neurological deficits, resulting in a lack of histological grading and (molecular) risk stratification. In this prospective explorative biomarker study, extracellular vesicles in the bloodstream will be investigated in patients with macroscopic meningiomas to identify a biomarker for molecular risk stratification and disease monitoring.

METHODS

In total, 60 patients with meningiomas and an indication of radiotherapy (RT) and macroscopic tumor on the planning MRI will be enrolled. Blood samples will be obtained before the start, during, and after radiotherapy, as well as during clinical follow-up every 6 months. Extracellular vesicles will be isolated from the blood samples, quantified and correlated with the clinical treatment response or progression. Further, nanopore sequencing-based DNA methylation profiles of plasma EV-DNA will be generated for methylation-based meningioma classification.

DISCUSSION

This study will explore the dynamic of plasma EVs in meningioma patients under/after radiotherapy, with the objective of identifying potential biomarkers of (early) tumor progression. DNA methylation profiling of plasma EVs in meningioma patients may enable molecular risk stratification, facilitating a molecularly-guided target volume delineation and adjusted dose prescription during RT treatment planning.

Scalp necrosis following preoperative endovascular embolisation of the superficial temporal artery for meningioma

A woman in her late 50s with a left frontal lobe convexity meningioma underwent an elective endovascular embolisation of the left middle meningeal artery and distal branches of the left superficial temporal artery prior to surgical resection of the tumour. On postoperative day 46, she developed scalp necrosis, leading to poor wound healing requiring wound debridement and a complex plastic surgery reconstruction with a rotational flap. Endovascular embolisation of vascular tumours prior to surgical resection does not come without risks. The lack of consistency in the literature regarding indication, technique and outcomes makes it difficult to define the exact role of preoperative meningioma embolisation.

Perifocal edema is a risk factor for preoperative seizures in patients with meningioma WHO grade 2 and 3

BACKGROUND

Patients with intracranial meningiomas frequently suffer from tumor-related seizures prior to resection, impacting patients' quality of life. We aimed to elaborate on incidence and predictors for seizures in a patient cohort with meningiomas WHO grade 2 and 3.

METHODS

We retrospectively searched for patients with meningioma WHO grade 2 and 3 according to the 2021 WHO classification undergoing tumor resection. Clinical, histopathological and imaging findings were collected and correlated with preoperative seizure development. Tumor and edema volumes were quantified.

RESULTS

Ninety-five patients with a mean age of 59.5 ± 16.0 years were included. Most tumors (86/95, 90.5%) were classified as atypical meningioma WHO grade 2. Nine of 95 tumors (9.5%) corresponded to anaplastic meningiomas WHO grade 3, including six patients harboring TERT promoter mutations. Meningiomas were most frequently located at the convexity in 38/95 patients (40.0%). Twenty-eight of 95 patients (29.5%) experienced preoperative seizures. Peritumoral edema was detected in 62/95 patients (65.3%) with a median volume of 9 cm3 (IR: 0-54 cm3). Presence of peritumoral edema but not age, tumor localization, TERT promoter mutation, brain invasion or WHO grading was associated with incidence of preoperative seizures, as confirmed in multivariate analysis (OR: 6.61, 95% CI: 1.18, 58.12, p = *0.049). Postoperative freedom of seizures was achieved in 91/95 patients (95.8%).

CONCLUSIONS

Preoperative seizures were frequently encountered in about every third patient with meningioma WHO grade 2 or 3. Patients presenting with peritumoral edema on preoperative imaging are at particular risk for developing tumor-related seizures. Tumor resection was highly effective in achieving seizure freedom.

Efficacy and toxicity of bimodal radiotherapy in WHO grade 2 meningiomas following subtotal resection with carbon ion boost: Prospective phase 2 MARCIE trial

BACKGROUND

Novel radiotherapeutic modalities using carbon ions provide an increased relative biological effectiveness (RBE) compared to photons, delivering a higher biological dose while reducing radiation exposure for adjacent organs. This prospective phase 2 trial investigated bimodal radiotherapy using photons with carbon-ion (C12)-boost in patients with WHO grade 2 meningiomas following subtotal resection (Simpson grade 4 or 5).

METHODS

A total of 33 patients were enrolled from July 2012 until July 2020. The study treatment comprised a C12-boost (18 Gy [RBE] in 6 fractions) applied to the macroscopic tumor in combination with photon radiotherapy (50 Gy in 25 fractions). The primary endpoint was the 3-year progression-free survival (PFS), and the secondary endpoints included overall survival, safety and treatment toxicities.

RESULTS

With a median follow-up of 42 months, the 3-year estimates of PFS, local PFS and overall survival were 80.3%, 86.7%, and 89.8%, respectively. Radiation-induced contrast enhancement (RICE) was encountered in 45%, particularly in patients with periventricularly located meningiomas. Patients exhibiting RICE were mostly either asymptomatic (40%) or presented immediate neurological and radiological improvement (47%) after the administration of corticosteroids or bevacizumab in case of radiation necrosis (3/33). Treatment-associated complications occurred in 1 patient with radiation necrosis who died due to postoperative complications after resection of radiation necrosis. The study was prematurely terminated after recruiting 33 of the planned 40 patients.

CONCLUSIONS

Our study demonstrates a bimodal approach utilizing photons with C12-boost may achieve a superior local PFS to conventional photon RT, but must be balanced against the potential risks of toxicities.

Predictive factors of the postoperative proptosis recovery in surgery of spheno-orbital meningiomas

OBJECTIVE

This study aimed to identify factors affecting proptosis recovery in spheno-orbital meningioma (SOM) surgery and assess functional and oncological outcomes.

METHODS

Data from 32 consecutive SOM surgery cases (2002-2021) were analyzed. Clinical, radiological, operative, and oncological parameters were examined. Proptosis was assessed using the exophthalmos index (EI) on MRI or CT scans. Statistical analyses were performed to identify predictive factors for proptosis recovery.

RESULTS

Proptosis improved in 75% of patients post-surgery (EI decreased from 1.28 ± 0.16 to 1.20 ± 0.13, p = 0.048). Patients with stable or worsened EI had higher body mass index (28.5 ± 7.9 vs. 24.1 ± 4.7, p = 0.18), Simpson grade (IV 75% vs. 65%, p = 0.24), and middle sphenoid wing epicenter involvement (63% vs. 38%, p = 0.12), but no significant factors were associated with unfavorable exophthalmos outcomes. The improvement group had higher en plaque morphology, infratemporal fossa invasion, and radiation treatment for cavernous sinus residual tumor (88% vs. 75%, p = 0.25; 51% vs. 25%, p = 0.42; 41% vs. 25%, p = 0.42, respectively), but without statistical significance. Visual acuity remained stable in 78%, improved in 13%, and worsened in 9% during follow-up. Surgery had a positive impact on preoperative oculomotor nerve dysfunction in 3 of 4 patients (75%). Postoperative oculomotor nerve dysfunction was observed in 25%, of which 75% fully recovered. This occurrence was significantly associated with irradiation of an orbital tumor residue (p = 0.04). New postoperative trigeminal hypoesthesia was observed in 47%, of which 73% recovered. All SOMs were classified as WHO grade 1, and complementary treatments achieved oncological control, requiring gamma-knife radiosurgery in 53% and standard radiotherapy in 6%.

CONCLUSIONS

Surgery effectively improves proptosis in SOM, though complete resolution is rare. The absence of predictive factors suggests multifactorial causes, including body mass index and tumor resection grade. Postoperative oculomotor nerve dysfunction and trigeminal hypoesthesia are common but often recover. Gamma-knife radiosurgery maintains long-term oncological control for evolving tumor residue.

Sinus reconstruction therapy for superior sagittal sinus dural arteriovenous fistula caused by parasagittal meningioma invasion: a case report

A dural arteriovenous fistula (dAVF) involving the superior sagittal sinus (SSS) is relatively rare, and its clinical course is usually aggressive. Its concomitance with a tumor has rarely been reported. Here, we present a case of SSS dAVF due to meningioma invasion, which was treated with sinus reconstruction and endovascular embolization. A 75-year-old man who had undergone tumor resection for parasagittal meningioma 4 years prior presented with intra-ventricular hemorrhage. Computed tomography angiography and magnetic resonance imaging revealed recurrent tumor invasion into the SSS causing occlusion. Cerebral angiography revealed multiple shunts along the occluded segment of the SSS, diffuse deep venous congestion, and cortical reflux. Borden type 3 SSS dAVF was diagnosed. We first performed direct tumor resection, followed by stenting for the occluded SSS and partial embolization of the shunts. After a 6-month interval, transvenous occlusion of the SSS was performed along the stent, resulting in complete obliteration of the dAVF. Sinus reconstruction therapy was effective in the immediate improvement of venous hypertension, obtaining the access route to the fistulas, and eradicating the shunts.

Surgical Outcome of Torcula Herophili Meningioma: An Institutional Experience

INTRODUCTION

Resection of meningiomas (THMs) at the torcular Herophili poses challenges to surgeons due to complex regional anatomy. The current study aims to evaluate factors affecting the extent of resections, progression-free survival, and the role of radiation.

METHODS

We did a retrospective study of all the THM patients treated at our institute between May 1987 and June 2022. The demographic data, signs and symptoms, surgical notes, postoperative details, and radiotherapy were gathered retrospectively. Survival analysis was done with Kaplan-Meier tests along with predictors of the extent of resection as well as recurrence.

RESULTS

A total of 39 patients qualified to be included in the study, with 10 male patients (male:female 1:2.9) and an average age of 50.8 years. The average follow-up duration was 75.9 months. Simpson's grade 2 excision was achieved in 19 (48.7%) patients, followed by Simpson's grade 3 excision in 17 patients (43.6%). Progression-free survival in subtotal resection was 60 months, and 100 months in gross total resection. Statistically, the extent of the resection was determined by the involvement of sinuses/torcula and the number of quadrants involved around torcula. A total of 16 patients received radiosurgery for the residual or small reccurrence of the lesion. Follow-up revealed reccurrence in 5 cases.

CONCLUSIONS

Torcular meningiomas are relatively uncommon, described in few reports, and represent a therapeutic dilemma. Though some experts recommend complete removal of tumor and reconstruction of the sinus, others suggest maximum safe resection, followed by radiosurgery. The present study reflects reasonable control of the residual lesion with radiosurgery after maximum safe resection.

Unveiling the Efficacy of Gamma Knife Radiosurgery for Tectal Plate Gliomas

BACKGROUND AND OBJECTIVES

Tectal plate gliomas (TPGs) are midbrain tumors that grow slowly and have a benign clinical course. Most TPGs are low-grade astrocytomas, but they can encompass various histological tumor types. Gamma Knife radiosurgery (GKRS) is being explored as a potentially safe and effective treatment option for TPGs, although research in this area is limited. This study aims to evaluate GKRS's efficacy and safety in patients with TPG and provide a comprehensive review of existing literature on the topic.

METHODS

This retrospective, single-center study included 48 patients with consecutive TPG who underwent GKRS between September 2005 and June 2022. Patients diagnosed with TPGs based on radiological or tissue-based criteria and who had a minimum follow-up period of 12 months were eligible for inclusion. The primary end points were local control and the absence of GKRS-associated or tumor-associated mortality and morbidity.

RESULTS

During a median follow-up of 28.5 months (range, 12-128), the radiological assessment showed tumor control in all cases, with 16.7% achieving a complete response and 68.8% achieving a partial response. Pseudoprogression occurred in 6.2% of cases, with onset ranging from 3 to 8 months. Clinical outcomes revealed no permanent neurological deterioration, with symptoms improving in 14.6% of patients and remaining stable in the others. One patient in the pseudoprogression group experienced transient Parinaud syndrome. One patient died during follow-up because of unrelated causes. The mean survival time after GKRS was 123.7 months. None of the clinical, radiological, or radiosurgical variables showed a correlation with partial/complete response, clinical improvement, or overall survival.

CONCLUSION

There is limited research available on the management of TPGs, and this study presents the largest patient cohort treated with GKRS, along with a substantial follow-up duration. Despite its limitations, this study demonstrates the efficacy and low-risk profile of GKRS for TPGs.

Transpalpebral mini-orbitozygomatic approach for nonvascular skull base lesions: a single neurosurgeon's experience

OBJECTIVE

The authors aim to describe the advantages, utility, and disadvantages of the transpalpebral mini-orbitozygomatic (MOZ) approach for tumors of the lateral and superior orbit, orbital apex, anterior clinoid, anterior cranial fossa, middle cranial fossa, and parasellar region.

METHODS

The surgical approach from skin incision to closure is described while highlighting key technical and anatomical considerations, and cadaveric dissection demonstrates the surgical steps and focuses on important anatomy. Intraoperative images were included to supplement the cadaveric dissection. A retrospective review of adults who had undergone the MOZ approach for nonvascular pathology performed by a single neurosurgeon from 2017 to 2023 was included in this institutional review board-approved study. Descriptive statistics was used to summarize the data. Four representative cases were included to demonstrate the utility of the MOZ approach.

RESULTS

The study included 65 patients (46 female, 19 male), average age 54.84 years, who had undergone transpalpebral MOZ surgery. Presenting symptoms included visual changes (53.8% of cases), vision loss (23.1%), diplopia (21.8%), and proptosis (13.8%). The optic nerve and optic chiasm were involved in 32.3% and 10.8% of cases, respectively. The most common pathology was meningioma (81.5% of cases), and gross-total resection was achieved in 50% of all cases. Major complications included an infection and a carotid injury. Improvement of preoperative symptoms was reported in 92.2% of cases. Visual acuity improved in 12 patients. The mean follow-up was 8.57 ± 8.45 months.

CONCLUSIONS

The MOZ approach is safe and durable. The transpalpebral incision provides better cosmesis and functional outcomes than those of standard anterolateral approaches to the skull base. Careful consideration of the limits of the approach is paramount to appropriate application on a case-by-case basis. Further quantitative anatomical studies can help to define and compare the utility of the approach to open cranio-orbital and endoscopic transorbital approaches.

Combined Transpetrosal Approach: 2-Dimensional Operative Video

INDICATIONS CORRIDOR AND LIMITS OF EXPOSURE

This approach is suitable for petroclival lesions medial to V cranial nerve that extend in both middle and posterior fossa. It provides multiple surgical corridors with minimal brain retraction.

ANATOMIC ESSENTIALS NEED FOR PREOPERATIVE PLANNING AND ASSESSMENT

Several critical neurovascular structures of the petrous bone are at risk during the approach. Meticulous reading of the preoperative images is fundamental. It is mandatory to perform a thin section computed tomography scan, an MRI, and, in case of petroclival meningiomas, a digital subtraction angiography.

ESSENTIAL STEPS OF THE PROCEDURE

In the first illustrative case, we present our current "mini-combined petrosectomy" with minimal drilling of the labyrinth. Positioning, skin incision, and craniotomy are illustrated in the video. Once all the important neurovascular structures are identified, we perform the anterior and the posterior petrosectomy, with preservation of the endolymphatic sac. We continue with dura mater opening and tentorium cutting. After tumor removal, we can appreciate an unique view of ipsilateral and contralateral cranial nerves, as well as pituitary stalk and major arteries.

PITFALLS/AVOIDANCE OF COMPLICATIONS

To avoid injuries to the main neurovascular structures, neuronavigation, neuromonitoring, and Doppler can be useful.

VARIANTS AND INDICATIONS FOR THEIR USE

The second illustrative case shows an extension of the combined petrosectomy to the anterior fossa, this made possible to perform a transsylvian approach for this giant sphenopetroclival meningioma. The patients consented to the procedure and to the publication of his/her images. Appropriate consent was obtained for the publication of the cadaveric images.

Surgical Management and Outcome of the Planum Sphenoidale Meningioma: A Single-Center Strobe Compliant Study

BACKGROUND

The resection of the jugum (planum) sphenoidale meningioma (JSM) is challenging, and there is a scarcity of available data in the literature. This study aimed to describe the surgical management and long-term outcome of jugum sphenoidale meningioma.

METHODS

This was a retrospective, single-center, cohort study of 91 JSM patients treated in our department from 2005 to 2022. All the included patients have undergone surgical treatment. Clinical, radiologic, and surgical data were extracted with specific attention to the age at onset, family history, duration from symptoms to diagnosis, clinical presentation, quality of excision, recurrence, and treatment outcome.

RESULTS

WHO grade I and grade II meningioma were 83.5% (n = 76) and 16.5% (n = 15) respectively. Fronto-lateral 42.9% (n = 39) and pterional approaches 57.1% (n = 52) were the 2 major surgical approaches used for the management of planum sphenoidale meningioma. Twelve patients needed emergency surgical treatment at admission: 4 (4.4%) External CSF Shunt and 8 (8.8%) VP-Shunt. We have found a statistically significant (P = 0.032) association between the quality of excision and the risk of recurrence. The GTR (Hazard ratio = 1) of the planum meningioma protects the patient from recurrence within 60 months of follow-up. Postoperative complications encountered were CSF-Leak in 2.2%, Meningitis 4.4%, surgical site infection 2.2%, and surgical site hematoma 3.3%. The overall postoperative favorable outcome was 68.1% (n = 62).

CONCLUSIONS

The pterional approach has allowed the achievement of GTR for jugum sphenoidale meningioma with protective odds from recurrence risk.

Clinical outcomes and complications of eyelid versus eyebrow approaches to supraorbital craniotomy: systematic review and indirect meta-analysis

OBJECTIVE

Eyebrow supraorbital craniotomy is a versatile keyhole technique for treating intracranial pathologies. The eyelid supraorbital approach, an alternative approach to an eyebrow supraorbital craniotomy, has not been widely adopted among most neurosurgeons. The purpose of this systematic review and meta-analysis was to perform a pooled analysis of the complications of eyebrow or eyelid approaches for the treatment of aneurysms, meningiomas, and orbital tumors.

METHODS

A systematic review of the literature in the PubMed, Embase, and Cochrane Review databases was conducted for identifying relevant literature using keywords such as "supraorbital," "eyelid," "eyebrow," "tumor," and "aneurysm." Eyebrow supraorbital craniotomies with or without orbitotomies and eyelid supraorbital craniotomies with orbitotomies for the treatment of orbital tumors, intracranial meningiomas, and aneurysms were selected. The primary outcomes were overall complications, cosmetic complications, and residual aneurysms and tumors. Secondary outcomes included five complication domains: orbital, wound-related, scalp or facial, neurological, and other complications.

RESULTS

One hundred three articles were included in the synthesis. The pooled numbers of patients in the eyebrow and eyelid groups were 4689 and 358, respectively. No differences were found in overall complications or cosmetic complications between the eyebrow and eyelid groups. The proportion of residuals in the eyelid group (11.21%, effect size [ES] 0.26, 95% CI 0.12-0.41) was significantly higher (p < 0.05) than that in the eyebrow group (6.17%, ES 0.10, 95% CI 0.08-0.13). A subgroup analysis demonstrated significantly higher incidences of orbital, wound-related, and scalp or facial complications in the eyelid group (p < 0.05), but higher other complications in the eyebrow group. Performing an orbitotomy substantially increased the complication risk.

CONCLUSIONS

This is the first meta-analysis that quantitatively compared complications of eyebrow versus eyelid approaches to supraorbital craniotomy. This study found similar overall complication rates but higher rates of selected complication domains in the eyelid group. The literature is limited by a high degree of variability in the reported outcomes.

Adjuvant Stereotactic Radiosurgery for Clear Cell Meningiomas

OBJECTIVE

Clear cell meningiomas (CCM) are an uncommon meningioma subtype marked by aggressive growth and high rates of recurrence despite initial resection. The present study evaluates the adjuvant benefit of stereotactic radiosurgery (SRS) for residual or recurrent tumors.

METHODS

After review of our prospectively maintained database, we identified 6 patients (3 female) with histologically confirmed Grade 2 CCMs. The median age of the patients at the time of SRS was 45 years. Five patients had undergone prior gross total surgical resection and 1 patient had subtotal resection before SRS. The median SRS treatment volume was 4.7 cc and the median radiosurgical margin dose was 13 Gy (range: 10-15 Gy).

RESULTS

The median follow-up time was 35.5 months (range 6-168 months). Three patients achieved tumor control after the first SRS procedure. Three patients experienced tumor progression at 4, 22, and 32 months after initial SRS. Tumor control was obtained in 2 of these patients after additional SRS. One patient with multiple SRS procedures had suspected adverse radiation effect that was successfully treated with corticosteroids followed by bevacizumab.

CONCLUSIONS

Tumor control was maintained in 5 of 6 patients after one or more SRS procedures. SRS should be considered for early intervention after surgical resection of CCM. To maximize the tumor control rate, patients with diagnosed CCM should be treated more generously and higher margin dose should be prescribed. Patients with CCM should be counselled that more than one SRS may be necessary to provide sustained tumor control.

Digital 3D Exoscope is Safe and Effective in Surgery for Intradural Extramedullary Tumors: A Comparative Series

BACKGROUND

Digital 3D exoscopes have been shown to be comparably safe and effective as surgical microscopes in complex microneurosurgical procedures. However, the results of exoscopic spinal tumor surgeries are scarce. The purpose of this study is to compare results of a transition from microscope to exoscope in surgeries for spinal intradural extramedullary tumors.

METHODS

We included all consecutive patients with intradural extramedullary spinal tumors operated on by the senior author during January 2016 to October 2023. The 3D exoscope was used in the latter half of the series from November 2020. We evaluated pre- and postoperative clinical findings, imaging studies, intra- and postoperative events, and analyzed surgical videos from the operations retrospectively.

RESULTS

We operated 35 patients (exoscope n = 19, microscope n = 16) for intradural extramedullary tumors (meningioma n = 18, schwannoma n = 12, other n = 5). Tumors in the cervical and thoracic spine were more common than in the lumbar region. The duration of surgery was slightly longer (median 220 vs. 185 minutes) in the exoscope group. However, the rate of gross total resection of the tumor was higher (81% vs. 67%) and the tumors more often located anteriorly to the spinal cord (42% vs. 13%) in the exoscope group. No major complications (i.e., permanent motor deficit or postoperative hematoma) occurred in either group. We saw postoperative gait improvement in 81% and 85% of the patients with preoperative deterioration of gait after exoscopic and microscopic surgeries, respectively.

CONCLUSIONS

This study demonstrates that exoscope-assisted surgery for spinal intradural extramedullary tumors is comparable in safety and effectiveness to traditional microscopic surgery.

Volumetric Analysis of Spheno-Orbital Meningiomas: Prognostic Correlation and a Compartmentalized Approach

BACKGROUND AND OBJECTIVES

Spheno-orbital meningiomas arise from the arachnoid villi cap cells at the sphenoid ridge and have the ability to spread through soft tissue extension and cranial bone invasion. Owing to their orbital hyperostosis and intraorbital soft tissue extension, they commonly present with ophthalmologic manifestations. This study aims to investigate the correlation between tumor volume with the presenting symptoms and postoperative outcomes.

METHODS

This retrospective study analyzed patients who underwent surgical resection of spheno-orbital meningiomas. Tumor volumes in different compartments were measured using preoperative and postoperative imaging. Linear and logistic regression analyses were used to identify correlations between tumor volumes and presenting symptoms preoperatively and postoperative outcomes.

RESULTS

Sixty-six patients were included in this study, of whom 86.4% had proptosis, 80.3% had decreased visual acuity (VA), 30.3% had visual field defects, and 13.6% had periorbital edema. Preoperatively, proptosis linearly correlated with intraosseous tumor volume (coefficient = 0.6, P < .001), while the decrease in baseline VA correlated with the intraorbital tumor volume (coefficient = 0.3, P = .01). The odds of periorbital edema were found to increase with an increase in intraosseous tumor volume with an adjusted odds ratio of 1.4 (95% CI, 1.1-1.7, P = .003), while the odds of visual field defects were found to increase with an increase in intraorbital tumor volume with an adjusted odds ratio of 2.7 (95% CI, 1.3-5.6, P = .01). Postoperatively, the volume of intraosseous tumor resected linearly correlated with the improvement in proptosis (coefficient = 0.7, P < .001), while the volume of intraorbital tumor resected linearly correlated with improvement in VA (coefficient = 0.5, P < .001) and with a larger effect size in patients presenting with moderate-to-severe decrease in VA preoperatively (coefficient = 0.8).

CONCLUSION

Underscoring the importance of each tumor compartment relative to the patient's symptomatology serves as a valuable guide in implementing a compartmentalized resection approach tailored to the surgical objectives.

Intraventricular meningioma resection and visual outcomes

OBJECTIVE

Intraventricular meningiomas (IVMs) of the lateral ventricle are rare tumors that present surgical challenges because of their deep location. Visual field deficits (VFDs) are one risk associated with these tumors and their treatment. VFDs may be present preoperatively due to the tumor and mass effect (tumor VFDs) or may develop postoperatively due to the surgical approach (surgical VFDs). This institutional series aimed to review surgical outcomes following resection of IVMs, with a focus on VFDs.

METHODS

Patients who received IVM resection at one academic institution between the years 1996 and 2021 were retrospectively reviewed. Diffusion tensor imaging (DTI) reconstructions of the optic radiations around the tumor were performed from preoperative IVM imaging. The VFD course and resolution were documented.

RESULTS

Thirty-two adult patients underwent IVM resection, with gross-total resection in 30 patients (93.8%). Preoperatively, tumor VFDs were present in 6 patients, resolving after surgery in 5 patients. Five other patients (without preoperative VFD) had new persistent surgical VFDs postoperatively (5/32, 15.6%) that persisted to the most recent follow-up. Of the 5 patients with persistent surgical VFDs, 4 received a transtemporal approach and 1 received a transparietal approach, and all these deficits occurred prior to regular use of DTI in preoperative imaging.

CONCLUSIONS

New surgical VFDs are a common neurological deficit after IVM resection. Preoperative DTI may demonstrate distortion of the optic radiations around the tumor, thus revealing safe operative corridors to prevent surgical VFDs.

Endoscopic endonasal approach for olfactory groove meningioma resection: Strategies and outcomes in a retrospective case series

OBJECTIVE

Though the endoscopic endonasal approach (EEA) is a widely accepted treatment for skull base tumors, the specific use of EEA for olfactory groove meningiomas (OGMs) is debated, with variable outcomes reported in the literature. We review the surgical results of OGM resections for one surgeon including the operative approach, surgical nuances, and outcomes, with a focus on factors relating to patient selection which favor EEA over transcranial approaches.

METHODS

We retrospectively reviewed thirteen cases of endoscopic endonasal resection of olfactory groove meningiomas. Patient characteristics, clinical characteristics, surgical outcomes, and complications were analyzed. Extent of resection was determined based on volumetric analysis of pre- and postoperative MRI.

RESULTS

Anatomic characteristics that render a tumor difficult to access fully are lateral extension beyond the mid-orbit and anterior extension to the falx. Simpson Grade I resection was achieved in 11/13 (84.6 %) cases. Mean pre-operative tumor volume was 8.99 cm3 (range 2.19-16.79 cm3), and 92 % of tumors were WHO grade I. We demonstrate 2 cases of smell preservation, possible with small unilateral tumors and tumors that are confined to either the anterior or posterior portion of the cribriform plate. The post-operative CSF leak rate was 7.7 %, without prophylactic lumbar CSF drainage. The mortality rate was 7.7 % (n = 1) after infectious complications following CSF leak.

CONCLUSIONS

Endoscopic endonasal resection of olfactory groove meningiomas is an effective and safe operative method with outcomes and complication rates comparable to transcranial approaches. Key considerations include careful patient selection and familiarity with technical nuances of endoscopic endonasal approach for this specific tumor type.

Transorbital neuroendoscopic surgery for treatment of sphenoid wing meningiomas extending to the cavernous sinus: clinical implications and a technical illustration

OBJECTIVE

The aim of this study was to evaluate the efficacy and safety of transorbital neuroendoscopic surgery (TONES) in the management of sphenoid wing meningiomas (SWMs) with cavernous sinus and orbital invasion.

METHODS

The authors conducted a retrospective review of 32 patients with SWMs treated at Gazi University using TONES from October 2019 to May 2023. The study includes clinical applications to elucidate the endoscopic transorbital approach. Surgical techniques focused on safe subtotal resection, aiming to minimize residual tumor volume for subsequent radiosurgery. Data were collected on patient demographics, tumor characteristics, surgical procedures, complications, and postoperative outcomes, including radiological imaging and ophthalmological evaluations.

RESULTS

Surgical dissections delineated a three-phase endoscopic transorbital approach: extraorbital, intraorbital, and intracranial. In the clinical application, gross-total resection was not achieved in any patient because of planned postoperative Gamma Knife radiosurgery. The mean follow-up period was 16.3 months. Of 30 patients with preoperative proptosis, 25 experienced postoperative improvement. No new-onset extraocular muscle paresis or visual loss occurred postoperatively. The average hospital stay was 1.15 days, with minimal complications and no significant morbidity or mortality.

CONCLUSIONS

Total resection of SWMs invading the cavernous sinus and orbit is associated with substantial risks, particularly cranial nerve deficits. TONES offers a minimally invasive alternative, reducing morbidity compared with transcranial approaches, and represents a significant advancement in the surgical management of SWMs, especially those extending into the cavernous sinus and orbit. The approach provides a safe, effective, and patient-centric approach, prioritizing subtotal resection to minimize neurological deficits while preparing patients for adjunctive radiosurgery. This study positions TONES as a transformative surgical technique, aligning therapeutic efficacy with neurovascular preservation and postoperative recovery.