The Role of Treatment-Related Parameters and Brain Morphology in the Lesion Volume of Magnetic-Resonance-Guided Focused Ultrasound Thalamotomy in Patients with Tremor-Dominant Neurological Conditions.

PURPOSE: To determine the best predictor of lesion volume induced by magnetic resonance (MR)-guided focused ultrasound (MRgFUS) thalamotomy in patients with tremor-dominant symptoms in Parkinson's disease (PD) and essential tremor (ET) patients. METHODS: Thirty-six neurological patients with medication-refractory tremor (n°19 PD; n°17 ET) were treated using a commercial MRgFUS brain system (Exablate Neuro 4000, Insightec) integrated with a 1.5 T MRI unit (Sigma HDxt; GE Medical System). Linear regression analysis was used to determine how the demographic, clinical, radiological (Fazekas scale), volumetric (total GM/WM/CSF volume, cortical thickness), and MRgFUS-related parameters [Skull Density Ratio (SDR), n° of transducer elements, n° of sonications, skull area, maximal energy delivered (watt), maximal power delivered (joule), maximal sonication time delivered, maximal mean temperature reached (T°C_max), accumulated thermal dose (ATD)] impact on ventral intermediate (VIM)-thalamotomy-related 3D volumetric lesions of necrosis and edema. RESULTS: The VIM thalamotomy was clinically efficacious in improving the tremor symptoms of all the patients as measured at 1 week after treatment. Multiple regression analysis revealed that T°C_max and n° of transducer elements were the best predictors of the necrosis and edema volumes. Moreover, total WM volume also predicted the size of necrosis. CONCLUSIONS: Our study provides new insights into the clinical MRgFUS procedures that can be used to forecast brain lesion size and improve treatment outcomes.

A novel 3D anatomical visualization system to avoid injuries of nerves in retrosigmoid approach.

The retro-sigmoid approach (RA), widely used during different neurosurgical procedures, is burdened by the risk of injuries of the nerves that cross that region contributing to possible postoperative complications. By using, anatomage table (AT), a novel 3D anatomical visualization system, we described the nerves passing through the retromastoid area including the great occipital nerve (GON), the lesser occipital nerve (LON) and the great auricular nerve (GAN), and their courses from the origins, till terminal branches. Moreover, using dedicated software, we measured distances between the nerves and well-recognizable bony landmarks. After identifying the nerves and their distances from bony landmarks, we observed that the safest and risk-free skin incision should be made in an area delimited, superiorly from the superior nuchal line (or slightly higher), and inferiorly from a plane passing at 1-1.5 cm above the mastoid tip. The lateral aspect of such an area should not exceed 9.5-10 cm from the inion, while the medial one should be more than 7 cm far from the inion. This anatomical information has been useful in defining anatomical landmarks and reducing the risk of complications, mainly related to nerve injury, in RA. In-depth neuroanatomic knowledge of the cutaneous nerves of the retromastoid area is essential to minimize the complications related to their injury during different neurosurgical approaches. Our findings suggest that the AT is a reliable tool to enhance understanding of the anatomy, and thus contributing to the refinement of surgical techniques.

Primary Intracranial Gliosarcoma: Is It Really a Variant of Glioblastoma? An Update of the Clinical, Radiological, and Biomolecular Characteristics.

Gliosarcomas (GS) are sporadic malignant tumors classified as a Glioblastoma (GBM) variant with IDH-wild type phenotype. It appears as a well-circumscribed lesion with a biphasic, glial, and metaplastic mesenchymal component. The current knowledge about GS comes from the limited literature. Furthermore, recent studies describe peculiar characteristics of GS, such as hypothesizing that it could be a clinical-pathological entity different from GBM. Here, we review radiological, biomolecular, and clinical data to describe the peculiar characteristics of PGS, treatment options, and outcomes in light of the most recent literature. A comprehensive literature review of PubMed and Web of Science databases was conducted for articles written in English focused on gliosarcoma until 2023. We include relevant data from a few case series and only a single meta-analysis. Recent evidence describes peculiar characteristics of PGS, suggesting that it might be a specific clinical-pathological entity different from GBM. This review facilitates our understanding of this rare malignant brain tumor. However, in the future we recommend multi-center studies and large-scale metanalyses to clarify the biomolecular pathways of PGS to develop new specific therapeutic protocols, different from conventional GBM therapy in light of the new therapeutic opportunities.

Attitudes toward the SARS-CoV-2 and Influenza Vaccination in the Metropolitan Cities of Bologna and Palermo, Italy.

Vaccine hesitancy (VH) is known to play a relevant role in thwarting the efforts toward reaching satisfactory influenza vaccination coverage, and has caused similar difficulties during the COVID-19 pandemic. This study aims to describe the phenomenon and produce insights on the reasons behind VH. A survey was administered between December 2020 and February 2021 to adults living in the cities of Bologna and Palermo. Of the 443 subjects enrolled, 47.3% were likely to get the influenza vaccination, while 75.6% were willing to receive the COVID-19 vaccination. The most frequent determinants that motivated the willingness to get the COVID-19 vaccine were trust in the safety of vaccines and belief that the vaccine is an effective tool. As for people's unwillingness to be vaccinated, being exposed to information that produced doubts about the vaccine and lack of trust in a newly developed vaccine were the most frequently involved determinants. Statistically significant positive associations were found between the willingness to be vaccinated and postgraduate education and the propensity towards influenza vaccination. A negative association with being over 40 years old and of female gender was also found. These results might have an impact in better understanding individual reasons behind VH, identifying which categories are more exposed to it and which strategies should be implemented.

Coronavirus Disease 2019 (COVID-19) and Neurosurgery: Literature and Neurosurgical Societies Recommendations Update.

BACKGROUND: Since January 2020, when the pathogen causing the coronavirus disease was identified in humans, the literature on coronavirus disease 2019 (COVID-19) has grown exponentially to more than 4000 publications. There is the need to provide an update for each single medical discipline, including neurosurgery, to be used by single professionals or to be distributed through the neurosurgical community and to be used by governments in designing new scenario of care. METHODS: A review of the MEDLINE database was performed on April 13, 2020. Search terms included "COVID-19," "neurosurgery," and "surgery." A review of documents published on the webpage of the WFNS (World Federation of Neurosurgical Societies) and of the 5 continental associations of neurosurgical societies, AANS (American Association of Neurological Surgeons), AASNS (Asian Australasian Society of Neurological Surgeons), CAANS (Continental Association of African Neurosurgical Societies), EANS (European Association of Neurosurgical Societies), and FLANC (Latin American Federation of Neurosurgical Societies), representing the 119 national neurosurgical societies around the world, was performed. RESULTS: The literature search yielded 38 results that were manually reviewed. Fourteen manuscripts were considered eligible. They described suggestions and considerations to optimize care of neurosurgical patients, editorials on operational models, perspectives from neurosurgical departments, letters to the editor describing experiences on how to help medical staff to be prepared in advance for pandemic situations, and descriptions of regional or departmental models and/or organizational schemes. The webpages of the searched societies reported a total of 57 documents. CONCLUSIONS: The neurosurgical scientific community has promptly reacted to the COVID-19 outbreak by producing a growing number of documents that could serve as guidance for neurosurgeons all over the world. Neurosurgical societies will represent the key institutions for guiding the neurosurgical community to overcome the COVID-19 crisis.

A Novel Technical Refinement of Microvascular Decompression: Pain Relief and Complication Rate in a Consecutive Series of Patients With Trigeminal Neuralgia.

BACKGROUND: Microvascular decompression (MVD) represents a milestone for the treatment of trigeminal neuralgia (TN). Nevertheless, several complications still occur and may negatively affect the outcome. We recently proposed some technical nuances for complication avoidance related to MVD. OBJECTIVE: To verify the efficacy of the proposed refinement of the standard MVD technique in terms of resolution of the pain and reduction of complication rates. METHODS: We analyzed surgical and outcome data of patients with TN using a novel surgical refinement to MVD, over the last 4 yr. Outcome variables included pain relief, facial numbness, muscular atrophy, local cutaneous occipital and temporal pain or numbness, cerebellar injury, hearing loss, cranial nerve deficits, wound infection, and cerebrospinal fluid (CSF) leak. Overall complication rate was defined as the occurrence of any of the aforementioned items. RESULTS: A total of 72 consecutive patients were enrolled in the study. Pain relief was achieved in 91.6% and 88.8% of patients at 1- and 4-yr follow-up, respectively. No patient reported postoperative facial numbness during the entire follow-up period. The incidence of CSF leak was 1.4%. One patient developed a complete hearing loss and another a minor cerebellar ischemia. There was no mortality. The overall complication rate was 5.6%, but only 1.4% of patients experienced permanent sequelae. CONCLUSION: The proposed refinement of the standard MVD technique has proved effective in maintaining excellent results in terms of pain relief while minimizing the overall complication rate associated with this surgical approach.

Gelatin-thrombin hemostatic matrix in neurosurgical procedures: hemostatic effectiveness and economic value of clinical and surgical procedure-related benefits.

BACKGROUND: Gelatin-thrombin hemostatic matrix (FloSeal®) use is associated with shorter surgical times and less blood loss, parameters that are highly valued in neurosurgical procedures. We aimed to assess the effectiveness of gelatin-thrombin in neurosurgical procedures and estimate its economic value. METHODS: In a 6-month retrospective evaluation at 2 hospitals, intraoperative and postoperative information were collected from patients undergoing neurosurgical procedures where bleeding was controlled with gelatin-thrombin matrix or according to local bleeding control guidelines (control group). Study endpoints were: length of surgery, estimated blood loss, hospitalization duration, blood units utilized, intensive care unit days, postoperative complications, and time to recovery. Statistical methods compared endpoints between the gelatin-thrombin and control groups and resource utilization costs were estimated. RESULTS: Seventy-eight patients (38 gelatin-thrombin; 40 control) were included. Gelatin-thrombin was associated with a shorter surgery duration than control (166±40 versus 185±55 minutes, P=0.0839); a lower estimated blood loss (185±80 versus 250±95 mL; P=0.0017); a shorter hospital stay (10±3 versus 13±3 days; P<0.001); fewer intensive care unit days (10 days/3 patients and 20 days/4 patients); and shorter time to recovery (3±2.2 versus 4±2.8 weeks; P=0.0861). Fewer gelatin-thrombin patients experienced postoperative complications (3 minor) than the control group (5 minor; 3 major). No gelatin-thrombin patient required blood transfusion; 5 units were administered in the control group. The cost of gelatin-thrombin (€ 268.40/unit) was offset by the shorter surgery duration (difference of 19 minutes at € 858/hour) and the economic value of improved the other endpoint outcomes (i.e., shorter hospital stay, lesser blood loss/lack of need for transfusion, fewer intensive care unit days, and complications). CONCLUSIONS: The use of gelatin-thrombin hemostatic matrix in patients undergoing neurosurgical procedures was associated with better intra- and postoperative parameters than conventional hemostasis methods, with these parameters having substantial economic benefits.

UAIS: Unruptured Aneurysms Italian Study.

BACKGROUND: Unruptured intracranial aneurysms (UIAs) are increasingly identified and are an important health-care burden; in the past they were commonly treated by surgical clipping, but nowadays endovascular coil embolization is increasingly employed as an alternative. METHODS: The Unruptured Aneurysms Italian Study (UAIS) is a multicentric cooperative prospective study aimed to delineate the "State of the Art" of UIAs treatment in Italy. 51 Italian Neurosurgical and Neuroradiological Units, representatives of all 20 Italian regions are involved in the Study. RESULTS: UAIS started on June 2003 and ended on July 2007. 1138 patients were collected by that date, but 181 were ruled-out due to severe violation of the protocol; 957 had complete data and could be statistically evaluated. CONCLUSIONS: UAIS demonstrates that the treatment of UAs, as performed in Italy as a Nation, is effective in improving long-term outcome vs. natural history, particularly in aneurysms larger than 7 mm.

Petrosal Meningiomas: Factors Affecting Outcome and the Role of Intraoperative Multimodal Assistance to Microsurgery.

BACKGROUND: Petrous meningiomas (PMs) represent a subset of posterior fossa tumors accounting for ∼8% of all intracranial meningiomas. Surgical treatment of PMs is challenging because of their relationships with vital neurovascular structures of the cerebellopontine angle. OBJECTIVE: To investigate independent pre- and intraoperative predictors of PM surgery outcome. METHODS: We reviewed the surgical and outcome data of patients who underwent microsurgical resection of PMs from 1997 to 2016. From 2007 onward, a multimodal intraoperative protocol consisting of intraoperative neuromonitoring (IONM), endoscopy, and indocyanine green (ICG) videoangiography was applied. Outcome variables included extent of resection, Karnofsky performance status (KPS), overall survival, and progression-free survival (PFS). RESULTS: A total of 54 patients were included. Independent predictors of gross total resection (GTR) included retromeatal location (P < .0175; odds ratio [OR] 4.05), absence of brainstem compression (P < .02; OR 3.55), and histological WHO grade I (P < .001; OR 3.47). Nongiant size (P < .012; OR 4.38), and WHO grade I (P < .0001; OR 7.7) were independent predictors of stable or improved KPS. The use of multimodal intraoperative tools to assist surgery independently predicted GTR (P < .002; OR 6.8) and good KPS (P < .018; OR 4.23). Nongiant size (P = .01) and WHO grade I (P = .002) were significantly associated with increased PFS. CONCLUSION: Notwithstanding the limitations of a retrospective study, our results suggest that support of microsurgery by a combination of IONM, endoscopy, and ICG videoangiography may improve patient outcome in PM surgery.

Surgery of language-eloquent tumors in patients not eligible for awake surgery: the impact of a protocol based on navigated transcranial magnetic stimulation on presurgical planning and language outcome, with evidence of tumor-induced intra-hemispheric plasticity.

OBJECTIVES: Awake surgery and intraoperative monitoring represent the gold standard for surgery of brain tumors located in the perisylvian region of the dominant hemisphere due to their ability to map and preserve the language network during surgery. Nevertheless, in some cases awake surgery is not feasible. This could increase the risk of postoperative language deficit. Navigated transcranial magnetic stimulation (nTMS) and nTMS-based DTI fiber tracking (DTI-FT) provide a preoperative mapping and reconstruction of the cortico-subcortical language network. This can be used to plan and guide the surgical strategy to preserve the language function. The objective if this study is to describe the impact of a non-invasive preoperative protocol for mapping the language network through the nTMS and nTMS-based DTI-FT in patients not eligible for awake surgery and thereby operated under general anesthesia for suspected language-eloquent brain tumors. PATIENTS AND METHODS: We reviewed clinical data of patients not eligible for awake surgery and operated under general anaesthesia between 2015 and 2016. All patients underwent nTMS language cortical mapping and nTMS-based DTI-FT of subcortical language fascicles. The nTMS findings were used to plan and guide the maximal safe resection of the tumor. The impact on postoperative language outcome and the accuracy of the nTMS-based mapping in predicting language deficits were evaluated. RESULTS: Twenty patients were enrolled in the study. The nTMS-based reconstruction of the language network was successful in all patients. Interestingly, we observed a significant association between tumor localization and the cortical distribution of the nTMS errors (p = 0.004), thereby suggesting an intra-hemispheric plasticity of language cortical areas, probably induced by the tumor itself. The nTMS mapping disclosed the true-eloquence of lesions in 12 (60%) of all suspected cases. In the remaining 8 cases (40%) the suspected eloquence of the lesion was disproved. The nTMS-based findings guided the planning and surgery through the visual feedback of navigation. This resulted in a slight reduction of the postoperative language performance at discharge that was completely recovered after one month from surgery. The accuracy of the nTMS-based protocol in predicting postoperative permanent deficits was significantly high, especially for false-eloquent lesions (p = 0.04; sensitivity 100%, specificity 57.14%, negative predictive value 100%, positive predicitive value 50%). CONCLUSIONS: The nTMS-based preoperative mapping allows for a reliable visualization of the language network, being also able to identify an intra-hemispheric tumor-induced cortical plasticity. It allows for a customized surgical strategy that could preserve post-operative language function. This approach should be considered as a support for neurosurgeons whenever approaching patients affected by suspected language-eloquent tumors but not eligible for awake surgery.

The Impact of Diffusion Tensor Imaging Fiber Tracking of the Corticospinal Tract Based on Navigated Transcranial Magnetic Stimulation on Surgery of Motor-Eloquent Brain Lesions.

BACKGROUND: Navigated transcranial magnetic stimulation (nTMS) enables preoperative mapping of the motor cortex (M1). The combination of nTMS with diffusion tensor imaging fiber tracking (DTI-FT) of the corticospinal tract (CST) has been described; however, its impact on surgery of motor-eloquent lesions has not been addressed. OBJECTIVE: To analyze the impact of nTMS-based mapping on surgery of motor-eloquent lesions. METHODS: In this retrospective case-control study, we reviewed the data of patients operated for suspected motor-eloquent lesions between 2012 and 2015. The patients underwent nTMS mapping of M1 and, from 2014, nTMS-based DTI-FT of the CST. The impact on the preoperative risk/benefit analysis, surgical strategy, craniotomy size, extent of resection (EOR), and outcome were compared with a control group. RESULTS: We included 35 patients who underwent nTMS mapping of M1 (group A), 35 patients who also underwent nTMS-based DTI-FT of the CST (group B), and a control group composed of 35 patients treated without nTMS (group C). The patients in groups A and B received smaller craniotomies (P = .01; P = .001), had less postoperative seizures (P = .02), and a better postoperative motor performance (P = .04) and Karnofsky Performance Status (P = .009) than the controls. Group B exhibited an improved risk/benefit analysis (P = .006), an increased EOR of nTMS-negative lesions in absence of preoperative motor deficits (P = .01), and less motor and Karnofsky Performance Status worsening in case of preoperative motor deficits (P = .02, P = .03) than group A. CONCLUSION: nTMS-based mapping enables a tailored surgical approach for motor-eloquent lesions. It may improve the risk/benefit analysis, EOR and outcome, particularly when nTMS-based DTI-FT is performed.

Frameless Stereotactic Radiosurgery for Treatment of Multiple Sclerosis-Related Trigeminal Neuralgia.

BACKGROUND: Trigeminal neuralgia (TN) affects 7% of patients with multiple sclerosis (MS). In such patients, TN is difficult to manage either pharmacologically and surgically. Radiosurgical rhizotomy is an effective treatment option. The nonisocentric geometry of radiation beams of CyberKnife introduces new concepts in the treatment of TN. Its efficacy for MS-related TN has not yet been demonstrated. METHODS: Twenty-seven patients with refractory TN and MS were treated. A nonisocentric beams distribution was chosen; the maximal target dose was 72.5 Gy. The maximal dose to the brainstem was <12 Gy. Effects on pain, medications, sensory disturbance, rate, and time of pain recurrence were analyzed. RESULTS: Median follow-up was 37 (18-72) months. Barrow Neurological Institute pain scale score I-III was achieved in 23/27 patients (85%) within 45 days. Prescription isodose line (80%) accounting for a dose of 58 Gy incorporated an average of 4.85 mm (4-6 mm) of the nerve and mean nerve volume of 26.4 mm3 (range 20-38 mm3). Seven out of 27 patients (26%) had mild, not bothersome, facial numbness (Barrow Neurological Institute numbness score II). The rate of pain control decreased progressively after the first year, and only 44% of patients retained pain control 4 years later. CONCLUSIONS: Frameless radiosurgery can be effectively used to perform retrogasserian rhizotomy. Pain relief was satisfactory and, with our dose/volume constraints, no sensory complications were recorded. Nonetheless, long-term pain control was possible in less than half of the patients. This is a limitation that CyberKnife radiosurgery shares with other techniques in MS patients.

Functional Reconstruction of Motor and Language Pathways Based on Navigated Transcranial Magnetic Stimulation and DTI Fiber Tracking for the Preoperative Planning of Low Grade Glioma Surgery: A New Tool for Preservation and Restoration of Eloquent Networks.

BACKGROUND: Surgery of low-grade gliomas (LGGs) in eloquent areas still presents a challenge. New technologies have been introduced to enable the performance of "functional", customized preoperative planning aimed at maximal resection, while reducing the risk of postoperative deficits. We describe our experience in the surgery of LGGs in eloquent areas using preoperative planning based on navigated transcranial magnetic stimulation (nTMS) and diffusion tensor imaging (DTI) tractography. METHODS: Sixteen patients underwent preoperative planning, using nTMS and nTMS-based DTI tractography. Motor and language functions were mapped. Preoperative data allowed for tailoring of the surgical strategy. The impact of these modalities on surgical planning was evaluated. Influence on functional outcome was analyzed in comparison with results in a historical control group. RESULTS: In 12 patients (75 %), nTMS added useful information on functional anatomy and surgical risks. Surgical strategy was modified in 9 of 16 cases (56 %). The nTMS "functional approach" provided a good outcome at discharge, with a decrease in postoperative motor and/or language deficits, as compared with controls (6 vs. 44 %; p = 0.03). CONCLUSIONS: The functional preoperative mapping of speech and motor pathways based on nTMS and DTI tractography provided useful information, allowing us to plan the best surgical strategy for radical resection; this resulted in improved postoperative neurological results.