History and evolution of surgical treatment for spasticity: a journey from neurotomy to selective dorsal rhizotomy.

The evolution of neurosurgical approaches to spasticity spans centuries, marked by key milestones and innovative practitioners. Probable ancient descriptions of spasmodic conditions were first classified as spasticity in the 19th century through the interventions of Dr. William John Little on patients with cerebral palsy. The late 19th century witnessed pioneering efforts by surgeons such as Dr. Charles Loomis Dana, who explored neurotomies, and Dr. Charles Sherrington, who proposed dorsal rhizotomy to address spasticity. Dorsal rhizotomy rose to prominence under the expertise of Dr. Otfrid Foerster but saw a decline in the 1920s due to emerging alternative procedures and associated complications. The mid-20th century saw a shift toward myelotomy but the revival of dorsal rhizotomy under Dr. Claude Gros' selective approach and Dr. Marc Sindou's dorsal root entry zone (DREZ) lesioning. In the late 1970s, Dr. Victor Fasano introduced functional dorsal rhizotomy, incorporating electrophysiological evaluations. Dr. Warwick Peacock and Dr. Leila Arens further modified selective dorsal rhizotomy, focusing on approaches at the cauda equina level. Later, baclofen delivered intrathecally via an implanted programmable pump emerged as a promising alternative around the late 1980s, pioneered by Richard Penn and Jeffrey Kroin and then led by A. Leland Albright. Moreover, intraventricular baclofen has also been tried in this matter. The evolution of these neurosurgical interventions highlights the dynamic nature of medical progress, with each era building upon and refining the work of significant individuals, ultimately contributing to successful outcomes in the management of spasticity.

Evaluation of the long-term effect of selective tibial neurotomy for the treatment of spastic foot using a personal goal-centered approach.

OBJECTIVE: The objective of this study was to evaluate the long-term effectiveness of selective tibial neurotomy (STN) for the treatment of the spastic foot using a goal-centered approach. METHODS: Between 2011 and 2018, adult patients with a spastic foot (regardless of etiology) who received STN followed by a rehabilitation program were included. The primary outcome was the achievement of individual goals defined preoperatively (T0) and compared at 1-year (T1) and 5-year (T5) follow-up by using the Goal Attainment Scaling methodology (T-score). The secondary outcomes were the presence of spastic deformities (equinus, varus, and claw toes), modified Ashworth scale (MAS) score for the targeted muscles, and modified Rankin Scale (mRS) score at T0, T1, and T5. RESULTS: Eighty-eight patients were included. At T5, 88.7% of patients had achieved their goals at least "as expected." The mean T-score was significantly higher at T1 (62.5 ± 9.5) and T5 (60.6 ± 11.3) than at T0 (37.9 ± 2.8) (p < 0.0001), and the difference between T1 and T5 was not significant (p = 0.2). Compared to T0, deformities (equinus, varus, and claw toes; all p < 0.0001), MAS score (p < 0.0001), and mRS score (p < 0.0001) were significantly improved at T1 and T5. Compared to T1, MAS score increased slightly only at T5 (p = 0.05) but remained largely below the preoperative value. There was no difference between T1 and T5 regarding other clinical parameters (e.g., deformities, walking abilities, mRS score). CONCLUSIONS: This study found that STN associated with a postoperative rehabilitation program can enable patients to successfully achieve personal goals that are sustained within a 5-year follow-up period.

Neurosurgical treatment of spasticity: a potential return to the cerebellum.

OBJECTIVE: Neurosurgical targeting of the cerebellar dentate nucleus via ablative dentatotomy and stimulation of the dentate nucleus was historically used for effective treatment of spasticity. Yet for decades, neurosurgical treatment of spasticity targeting the cerebellum was bypassed in favor of alternative treatments such as intrathecal baclofen pumps and selective dorsal rhizotomies. Cerebellar neuromodulation has recently reemerged as a promising and effective therapy for spasticity and related movement disorders. METHODS: In this narrative review, the authors contextualize the historical literature of cerebellar neuromodulation, comparing it with modern approaches and exploring future directions with regard to cerebellar neuromodulation for spasticity. RESULTS: Neurosurgical intervention on the cerebellum dates to the use of dentatotomy in the 1960s, which had progressed to electrical stimulation of the cerebellar cortex and dentate nucleus by the 1980s. By 2024, modern neurosurgical approaches such as tractography-based targeting of the dentate nucleus and transcranial magnetic stimulation of cerebellar cortex have demonstrated promise for treating spasticity. CONCLUSIONS: Cerebellar neuromodulation of the dentate nucleus and cerebellar cortex are promising therapies for severe cases of spasticity. Open areas for exploration in the field include the following: tractography-based targeting, adaptive cerebellar stimulation, and investigations into the network dynamics between the cerebellar cortex, deep cerebellar nuclei, and the subcortical and cortical structures of the cerebrum.

Endoscopic endonasal resection of symptomatic Rathke's cleft cysts: outcomes of the strategy to maintain the fenestration open.

PURPOSE: The study intends to clarify the optimal endoscopic endonasal surgical strategy for symptomatic Rathke's cleft cysts (RCCs). METHODS: We retrospectively analyzed patients with RCCs that underwent EEA surgery. The strategy for surgical and reconstruction method selection was presented. Patients were split into groups of fenestration open or closed. Pre- and postoperative symptoms, imaging, ophthalmologic, and endocrinologic exams were reviewed. The incidence of complications and the recurrence rates were determined. RESULTS: The 75 individuals were all received primary operations. The fenestration closed group contained 32 cases, while the fenestration open group contained 43 cases. The median follow-up period was 39 months. The three primary complaints were headache (n = 51, 68.00%), vision impairment (n = 45, 60.00%), and pituitary dysfunction (n = 16, 21.33%). Of the 51 patients with preoperative headaches, 48 (94.12%) reported improvement in their symptoms following surgery. Twenty-three out of 45 patients (51.11%) experienced an improvement in visual impairment. Pituitary dysfunction was found improved in 14 out of 16 individuals (87.50%). There was no discernible difference in the rate of symptom alleviation between both groups. There were three patients (3/75, 4.00%) had cyst reaccumulation. One of them (1/75, 1.33%), which needed reoperation, was healed using pterional approach. In term of complications, cerebral infections occurred in two patients (2/75, 2.67%). Both of them recovered after antibiotic treatment. No postoperative cerebrospinal fluid rhinorrhea occurred. One patient (1/75, 1.33%) in the open group experienced epistaxis. There was no persistent hypopituitarism or diabetes insipidus (DI). Analysis of headache related factors showed that the presence of wax like nodules was related to it. CONCLUSION: RCC was successfully treated with endoscopic endonasal surgery with few problems when the fenestration was kept as open as feasible. Preoperative identification of T2WI hypointense nodules may be a potential reference factor for surgical indication.

Comparative analysis of surgical techniques in the management of chronic subdural hematomas and risk factors for poor outcomes.

Chronic subdural hematomas (CSDH) are increasingly prevalent, especially among the elderly. Surgical intervention is essential in most cases. However, the choice of surgical technique, either craniotomy or burr-hole opening, remains a subject of debate. Additionally, the risk factors for poor long-term outcomes following surgical treatment remain poorly described. This article presents a 10-year retrospective cohort study conducted at a single center that aimed to compare the outcomes of two common surgical techniques for CSDH evacuation: burr hole opening and minicraniotomy. The study also identified risk factors associated with poor long-term outcome, which was defined as an mRS score ≥ 3 at 6 months. This study included 582 adult patients who were surgically treated for unilateral CSDH. Burr-hole opening was performed in 43% of the patients, while minicraniotomy was performed in 57%. Recurrence was observed in 10% of the cases and postoperative complications in 13%. The rates of recurrence, postoperative complications, death and poor long-term outcome did not differ significantly between the two surgical approaches. Multivariate analysis identified postoperative general complications, recurrence, and preoperative mRS score ≥ 3 as independent risk factors for poor outcomes at 6 months. Recurrence contribute to a poorer prognosis in CSDH. Nevertheless, use burr hole or minicraniotomy for the management of CSDH showed a similar recurrence rate and no significant differences in post-operative outcomes. This underlines the need for a thorough assessment of patients with CSHD and the importance of avoiding their occurrence, by promoting early mobilization of patients. Future research is necessary to mitigate the risk of recurrence, regardless of the surgical technique employed.

Comparison of hypotension incidence between remimazolam and propofol in patients with hypertension undergoing neurosurgery: prospective, randomized, single-blind trial.

BACKGROUND: Remimazolam, a newer benzodiazepine that targets the GABAA receptor, is thought to allow more stable blood pressure management during anesthesia induction. In contrast, propofol is associated with vasodilatory effects and an increased risk of hypotension, particularly in patients with comorbidities. This study aimed to identify medications that can maintain stable vital signs throughout the induction phase. METHODS: We conducted a single-center, two-group, randomized controlled trial to investigate and compare the incidence of hypotension between remimazolam- and propofol-based total intravenous anesthesia (TIVA). We selected patients aged between 19 and 75 years scheduled for neurosurgery under general anesthesia, who were classified as American Society of Anesthesiologists Physical Status I-III and had a history of hypertension. RESULTS: We included 94 patients in the final analysis. The incidence of hypotension was higher in the propofol group (91.3%) than in the remimazolam group (85.4%; P = 0.057). There was no significant difference in the incidence of hypotension among the various antihypertensive medications despite the majority of patients being on multiple medications. In comparison with the propofol group, the remimazolam group demonstrated a higher heart rate immediately after intubation. CONCLUSIONS: Our study indicated that the hypotension incidence of remimazolam-based TIVA was comparable to that of propofol-based TIVA throughout the induction phase of EEG-guided anesthesia. Both remimazolam and propofol may be equally suitable for general anesthesia in patients undergoing neurosurgery. TRIAL REGISTRATION: Clinicaltrials.gov (NCT05164146).

A guide to interpreting systematic reviews and meta-analyses in neurosurgery and surgery.

INTRODUCTION: Systematic reviews (SRs) and meta-analyses (MAs) are methods of data analysis used to synthesize information presented in multiple publications on the same topic. A thorough understanding of the steps involved in conducting this type of research and approaches to data analysis is critical for appropriate understanding, interpretation, and application of the findings of these reviews. METHODS: We reviewed reference texts in clinical neuroepidemiology, neurostatistics and research methods and other previously related articles on meta-analyses (MAs) in surgery. Based on existing theories and models and our cumulative years of expertise in conducting MAs, we have synthesized and presented a detailed pragmatic approach to interpreting MAs in Neurosurgery. RESULTS: Herein we have briefly defined SRs sand MAs and related terminologies, succinctly outlined the essential steps to conduct and critically appraise SRs and MAs. A practical approach to interpreting MAs for neurosurgeons is described in details. Based on summary outcome measures, we have used hypothetical examples to illustrate the Interpretation of the three commonest types of MAs in neurosurgery: MAs of Binary Outcome Measures (Pairwise MAs), MAs of proportions and MAs of Continuous Variables. Furthermore, we have elucidated on the concepts of heterogeneity, modeling, certainty, and bias essential for the robust and transparent interpretation of MAs. The basics for the Interpretation of Forest plots, the preferred graphical display of data in MAs are summarized. Additionally, a condensation of the assessment of the overall quality of methodology and reporting of MA and the applicability of evidence to patient care is presented. CONCLUSION: There is a paucity of pragmatic guides to appraise MAs for surgeons who are non-statisticians. This article serves as a detailed guide for the interpretation of systematic reviews and meta-analyses with examples of applications for clinical neurosurgeons.

Super-elderly, spinal surgery, evaluating the risks and benefits: a retrospective single-centre cohort study.

INTRODUCTION: An increasingly ageing population presents emerging healthcare challenges. Adequate clinical evaluation and understanding of outcome-predicting factors are integral to delivering safe spinal surgery to super-elderly patients. AIM: To evaluate spine surgery outcomes in patients aged 80 or above. METHODS: We retrospectively evaluated patients 80 years and above who underwent elective or emergency spinal surgery between 2017 and 2022. The Eurospine Surgery Classification (ESC) was used to classify operations into Large, Medium, and Small. We calculated and compared Clinical Frailty Scores (CFS) pre- and post-operatively. RESULTS: Two hundred forty-five patients met the inclusion criteria. Most were male (n = 145). The age range was 80 to 99 (mean 83.3). Most operations were elective (n = 151, 62%). In our cohort, 211, 22, 10,2 and 1 patients had degenerative, trauma, tumour, infective and vascular pathologies, respectively. According to the Eurospine classification, 201 (82.0%) had Minor spine surgery (63 emergently and 138 electively), 38 had Medium surgery (15.5% - 30 emergently and 8 electively), and 6 had Large surgery (2.4% - 1 emergently and 5 electively). 163 (66.5%) were discharged or under follow-up. There were 11 in-patient mortalities (4.5%). Outpatient mortality was 51 (20.8%), with the median time from surgery to death being 504.5 days, all the outpatient mortalities were neither non-spinal pathology nor spinal surgical related. CFS improved across the cohort, from 5 pre-operatively to 4 post-operatively (p < 0.001). CONCLUSION: Spine surgery in those over the 80s can be performed safely and improve their quality of life, as demonstrated by improvements in the CFS. Good patient selection and adequate pre-operative workup is essential, although it may not be possible in emergencies.

Factors affecting the extent of resection and neurological outcomes following transopercular resection of insular gliomas.

BACKGROUND: Surgical resection of insular gliomas is a challenge. TO resection is considered more versatile and has lower risk of vascular damage. In this study, we aimed to understand the factors that affect resection rates, ischemic changes and neurological outcomes and studied the utility of IONM in patients who underwent TO resection for IGs. METHODS: Retrospective analysis of 66 patients with IG who underwent TO resection was performed. RESULTS: Radical resection was possible in 39% patients. Involvement of zone II and the absence of contrast enhancement predicted lower resection rate. Persistent deficit rate was 10.9%. Although dominant lobe tumors increased immediate deficit and fronto-orbital operculum involvement reduced prolonged deficit rate, no tumor related factor showed significant association with persistent deficits. 45% of patients developed a postoperative infarct, 53% of whom developed deficits. Most affected vascular territory was lenticulostriate (39%). MEP changes were observed in 9/57 patients. 67% of stable TcMEPs and 74.5% of stable strip MEPs did not develop any postoperative motor deficits. Long-term deficits were seen in 3 and 6% patients with stable TcMEP and strip MEPs respectively. In contrast, 25% and 50% of patients with reversible strip MEP and Tc MEP changes respectively had persistent motor deficits. DWI changes were clinically more relevant when accompanied by MEP changes intraoperatively, with persistent deficit rates three times greater when MEP changes occurred than when MEPs were stable. CONCLUSION: Radical resection can be achieved in large, multizone IGs, with reasonable outcomes using TO approach and multimodal intraoperative strategy with IONM.

Association of 5-aminolevulinic acid fluorescence guided resection with photodynamic therapy in recurrent glioblastoma: a matched cohort study.

PURPOSE: Glioblastoma is a malignant and aggressive brain tumour that, although there have been improvements in the first line treatment, there is still no consensus regarding the best standard of care (SOC) upon its inevitable recurrence. There are novel adjuvant therapies that aim to improve local disease control. Nowadays, the association of intraoperative photodynamic therapy (PDT) immediately after a 5-aminolevulinic acid (5-ALA) fluorescence-guided resection (FGR) in malignant gliomas surgery has emerged as a potential and feasible strategy to increase the extent of safe resection and destroy residual tumour in the surgical cavity borders, respectively. OBJECTIVES: To assess the survival rates and safety of the association of intraoperative PDT with 5-ALA FGR, in comparison with a 5-ALA FGR alone, in patients with recurrent glioblastoma. METHODS: This article describes a matched-pair cohort study with two groups of patients submitted to 5-ALA FGR for recurrent glioblastoma. Group 1 was a prospective series of 11 consecutive cases submitted to 5-ALA FGR plus intraoperative PDT; group 2 was a historical series of 11 consecutive cases submitted to 5-ALA FGR alone. Age, sex, Karnofsky performance scale (KPS), 5-ALA post-resection status, T1-contrast-enhanced extent of resection (EOR), previous and post pathology, IDH (Isocitrate dehydrogenase), Ki67, previous and post treatment, brain magnetic resonance imaging (MRI) controls and surgical complications were documented. RESULTS: The Mantel-Cox test showed a significant difference between the survival rates (p = 0.008) of both groups. 4 postoperative complications occurred (36.6%) in each group. As of the last follow-up (January 2024), 7/11 patients in group 1, and 0/11 patients in group 2 were still alive. 6- and 12-months post-treatment, a survival proportion of 71,59% and 57,27% is expected in group 1, versus 45,45% and 9,09% in group 2, respectively. 6 months post-treatment, a progression free survival (PFS) of 61,36% and 18,18% is expected in group 1 and group 2, respectively. CONCLUSION: The association of PDT immediately after 5-ALA FGR for recurrent malignant glioma seems to be associated with better survival without additional or severe morbidity. Despite the need for larger, randomized series, the proposed treatment is a feasible and safe addition to the reoperation.

Hematocrit drift and outcomes in surgical patients with aneurysmal subarachnoid hemorrhage.

BACKGROUND: There is a paucity of conclusive evidence regarding the impact of downward drift in hematocrit levels among patients who have undergone surgical clipping for aneurysmal subarachnoid hemorrhage (aSAH). This study endeavors to explore the potential association between hematocrit drift and mortality in this specific patient population. METHODS: A cohort study was conducted, encompassing adult patients diagnosed with aSAH at a university hospital. The primary endpoint was follow-up mortality. Propensity score matching was employed to align patients based on their baseline characteristics. Discrimination capacity across various models was assessed and compared using net reclassification improvement (NRI). RESULTS: Among the 671 patients with aSAH in the study period, 118 patients (17.6%) experienced an in-hospital hematocrit drift of more than 25%. Following adjustment with multivariate regression analysis, patients with elevated hematocrit drift demonstrated significantly increased odds of mortality (aOR: 2.12, 95% CI: 1.14 to 3.97; P = 0.019). Matching analysis yielded similar results (aOR: 2.07, 95% CI: 1.05 to 4.10; P = 0.036). The inclusion of hematocrit drift significantly improved the NRI (P < 0.0001) for mortality prediction. When in-hospital hematocrit drift was served as a continuous variable, each 10% increase in hematocrit drift corresponded to an adjusted odds ratio of 1.31 (95% CI 1.08-1.61; P = 0.008) for mortality. CONCLUSIONS: In conclusion, the findings from this comprehensive cohort study indicate that a downward hematocrit drift exceeding 25% independently predicts mortality in surgical patients with aSAH. These findings underscore the significance of monitoring hematocrit and managing anemia in this patient population.

Advancements in Neurosurgical Intraoperative Histology.

Despite their relatively low incidence globally, central nervous system (CNS) tumors remain amongst the most lethal cancers, with only a few other malignancies surpassing them in 5-year mortality rates. Treatment decisions for brain tumors heavily rely on histopathological analysis, particularly intraoperatively, to guide surgical interventions and optimize patient outcomes. Frozen sectioning has emerged as a vital intraoperative technique, allowing for highly accurate, rapid analysis of tissue samples, although it poses challenges regarding interpretive errors and tissue distortion. Raman histology, based on Raman spectroscopy, has shown great promise in providing label-free, molecular information for accurate intraoperative diagnosis, aiding in tumor resection and the identification of neurodegenerative disease. Techniques including Stimulated Raman Scattering (SRS), Coherent Anti-Stokes Raman Scattering (CARS), Surface-Enhanced Raman Scattering (SERS), and Tip-Enhanced Raman Scattering (TERS) have profoundly enhanced the speed and resolution of Raman imaging. Similarly, Confocal Laser Endomicroscopy (CLE) allows for real-time imaging and the rapid intraoperative histologic evaluation of specimens. While CLE is primarily utilized in gastrointestinal procedures, its application in neurosurgery is promising, particularly in the context of gliomas and meningiomas. This review focuses on discussing the immense progress in intraoperative histology within neurosurgery and provides insight into the impact of these advancements on enhancing patient outcomes.

Role of Pericardial Patch in Neurosurgery: Institutional Experience.

INTRODUCTION: Dural closure is an important part of neurosurgery, failure which may lead to wound infection, pseudomeningoceles, meningitis, severe morbidity to a patient, and even mortality. In cases where primary dura closure is not possible, a bovine pericardial patch is a good alternative with the benefits of suturability and the ability to provide watertight closure, hence preventing Cerebrospinal Fluid (CSF) leak. The present study demonstrates the use of the bovine pericardial patch in both cranial and spinal disorders for dural closure as well as for transposition technique in microvascular decompression. OBJECTIVES: The aim of our study is to understand the advantages and feasibility of a bovine pericardial patch in various neurosurgical procedures. MATERIAL METHODS: Fifty-one patients were analyzed prospectively and followed up in which glutaraldehyde-free bovine pericardial patch was used in various cranial and spinal disorders. RESULTS: The most common indications where a bovine pericardial patch was used, in decreasing order of frequency, were meningioma excision surgery (47%), followed by Chiari malformation operated for foramen magnum decompression (17.6%), meningomyelocele (7.8%), spinal dural defects (7.8%), trigeminal neuralgia (5.8%), traumatic decompression with lax duraplasty (4%), glioma (4%), encephalocele (4%), and skull base defects (2%). Two patients had complications, one with CSF leak and the other had superficial wound infection, which were managed appropriately. CONCLUSIONS: The use of a bovine pericardial patch as a dural substitute in various cranial and spinal disorders is feasible with good outcomes, and it can be considered an ideal dural substitute.

Long-term outcome of primary clival chordomas: a single-center retrospective study with an emphasis on the timing of recurrences based on the primary treatment.

OBJECTIVE: This study aimed to provide data on extended outcomes in primary clival chordomas, focusing on progression-free survival (PFS) and overall survival (OS). METHODS: A retrospective single-center analysis was conducted on patients with clival chordoma treated between 1987 and 2022 using surgery, stereotactic radiosurgery, or proton radiation therapy (PRT). RESULTS: The study included 100 patients (median age 44 years, 51% male). Surgery was performed using the endoscopic endonasal approach in 71 patients (71%). Gross-total resection (GTR) or near-total resection (NTR) was attained in 39 patients (39%). Postoperatively, new cranial nerve deficits occurred in 7%, CSF leak in 4%, and meningitis in none of the patients. Radiation therapy was performed in 79 patients (79%), with PRT in 50 patients (50%) as the primary treatment. During the median follow-up period of 73 (interquartile range [IQR] 38-132) months, 41 recurrences (41%) and 31 deaths (31%) were confirmed. Patients with GTR/NTR had a median PFS of 41 (IQR 24-70) months. Patients with subtotal resection or biopsy had a median PFS of 38 (IQR 16-97) months. The median PFS of patients who received radiation therapy was 43 (IQR 26-86) months, while that of patients who did not receive radiation therapy was 18 (IQR 5-62) months. The Kaplan-Meier method showed that patients with GTR/NTR (p = 0.007) and those who received radiation therapy (p < 0.001) had longer PFS than their counterparts. The PFS rates following primary treatment at 5, 10, 15, and 20 years were 51%, 25%, 17%, and 7%, respectively. The OS rates at the same intervals were 84%, 60%, 42%, and 34%, respectively. Multivariate Cox regression analysis showed that age < 44 years (p = 0.02), greater extent of resection (EOR; p = 0.03), and radiation therapy (p < 0.001) were associated with lower recurrence rates. Another multivariate analysis showed that age < 44 years (p = 0.01), greater EOR (p = 0.04), and freedom from recurrence (p = 0.02) were associated with lower mortality rates. Regarding pathology data, brachyury was positive in 98%, pan-cytokeratin in 93%, epithelial membrane antigen in 85%, and S100 in 74%. No immunohistochemical markers were associated with recurrence. CONCLUSIONS: In this study, younger age, maximal safe resection, and radiation therapy were important factors for longer PFS in patients with primary clival chordomas. Preventing recurrences played a crucial role in achieving longer OS.

A comparison of endoscopic endonasal versus open approaches for skull base chordoma: a comprehensive National Cancer Database analysis.

OBJECTIVE: The authors of this study aimed to investigate independent prognostic factors of survival with a particular focus on comparing the safety and efficacy of endoscopic endonasal versus open approaches in the surgical management of skull base chordoma. METHODS: A retrospective National Cancer Database review of skull base chordoma patients was performed to capture resection cases from 2010 to 2020, evaluating overall survival (OS), early postoperative mortality, readmission rates, and hospital length of stay (LOS) between surgical approaches and the independent prognostication of death utilizing Cox multivariate regression analysis. RESULTS: Among the 736 patients included in the cohort, 456 patients (62.0%) and 280 patients (38.0%) underwent endoscopic endonasal and open resection, respectively. These values represent a rate of change over the study period of +4.1 versus -0.14 cases per year, respectively. Gross-total resection was achieved in 32.5% of cases. A positive margin status was found in 51.8% of cases. There was no association between extent of resection and surgical approach (p = 0.257). There was no difference in OS (p = 0.562), 30- and 90-day mortality (p = 0.209 and 0.126, respectively), and 30-day readmission (p = 0.438) between the two surgical groups. The mean LOS was reduced by 2.1 days in the endoscopic cohort (p = 0.013) compared with the open approach cohort. Finally, multivariate analysis revealed a tumor size ≥ 4 cm (HR 4.03, p = 0.005) and public insurance (HR 2.76, p = 0.004) as negative predictors of survival and treatment at an academic center (HR 0.36, p = 0.043) as a positive prognosticator of survival. CONCLUSIONS: The endoscopic endonasal approach has been increasingly utilized over time and touts noninferiority with respect to safety and efficacy with a marked improvement in LOS, which carries substantial implications for both healthcare costs and enhanced patient recovery. Future prospective studies are necessary to further delineate trends and surgical outcomes for skull base chordoma.

Supramarginal resection of skull base chordomas: proof of concept and preliminary outcomes.

OBJECTIVE: The mainstay of treatment for skull base chordoma (SBC) is maximal safe resection followed by radiotherapy. However, even after gross-total resection (GTR), the recurrence rate is high due to microscopic disease in the resection margins. Therefore, supramarginal resection (SMR) could be beneficial, as has been shown for sacral chordoma. The paradigm of postoperative radiation therapy for every patient has also begun to change, as molecular profiling has shown variability in the risk of recurrence. The aim of this study was to present the concept of SMR applied to SBC, along with an individualized decision for postoperative radiation therapy. METHODS: This is a retrospective analysis of all SBCs operated on by the senior author between 2018 and 2023. SMR was defined as negative histological margins of bone and/or dura mater, along with evidence of bone resection beyond the tumor margins in the craniocaudal and lateral planes on postoperative imaging. Tumors were classified into 3 molecular recurrence risk groups (group A, low risk; group B, intermediate risk; and group C, high risk). Postoperative radiation therapy was indicated in group C tumors, in group B chordomas without SMR, or in cases of patient preference. RESULTS: Twenty-two cases of SBC fulfilled the inclusion criteria. SMR was achieved in 12 (55%) cases, with a mean (range) amount of bone resection beyond the tumor margins of 10 (2-20) mm (+40%) in the craniocaudal axis and 6 (1-15) mm (+31%) in the lateral plane. GTR and near-total resection were each achieved in 5 (23%) cases. Three (19%) tumors were classified as group A, 12 (75%) as group B, and 1 (6%) as group C. Although nonsignificant due to the small sample size, the trends showed that patients in the SMR group had smaller tumor volumes (13.9 vs 19.6 cm3, p = 0.35), fewer previous treatments (33% vs 60% of patients, p = 0.39), and less use of postoperative radiotherapy (25% vs 60%, p = 0.19) compared to patients in the non-SMR group. There were no significant differences in postoperative CSF leak (0% vs 10%, p = 0.45), persistent cranial nerve palsy (8% vs 20%, p = 0.57), and tumor recurrence (8% vs 10%, p = 0.99; mean follow-up 15 months) rates between the SMR and non-SMR groups. CONCLUSIONS: In select cases, SMR of SBC appears to be feasible and safe. Larger cohorts and longer follow-up evaluations are necessary to explore the benefit of SMR and individualized postoperative radiation therapy on progression-free survival.

Structure-sparing resection for the management of cervical chordomas: a retrospective institutional series.

OBJECTIVE: Chordomas are a rare and relatively slow-growing malignancy of notochordal origin with a nearly 50% recurrence rate. Chordomas of the cervical spine are particularly challenging tumors given surrounding vital anatomical structures. Although standard in other areas of the spine, en bloc resection of cervical chordomas is exceedingly difficult and carries the risk of significant postoperative morbidity. Here, the authors present their institutional experience with 13 patients treated with a structure-sparing radical resection and adjuvant radiation for cervical chordomas. METHODS: Records of the standing senior author and institutional database of spinal surgeries were retrospectively reviewed for surgically managed cervical and high thoracic chordomas between 1997 and 2022. Chordomas whose epicenter was cervical but touched the clivus or had extension to the thoracic spine were included in this series. Clinical and operative data were gathered and analyzed for the index surgery and any revisions needed. Outcome metrics such as recurrence rates, complication rates, functional status, progression-free interval (PFI) and overall survival (OS) were evaluated. RESULTS: The median patient age at diagnosis was 57 (range 32-80) years. The median modified Rankin Scale (mRS) score at the time of presentation was 1 (range 0-4). Approximately 40% of tumors were located in the upper cervical spine (occiput-C2). The median time from diagnosis to surgery was 74.5 (range 10-483) days. Gross-total resection was achieved in just under 40% of patients. All patients received adjuvant radiotherapy. The mean duration of follow-up was 4.09 years, with a mean PFI of 3.80 (range 1.16-13.1) years. Five patients experienced recurrence (38.5%). The mean OS was 3.44 years. Three patients died during the follow-up period; 2 due to disease progression and 1 died in the immediate postoperative period. One patient was lost to follow-up. A significant positive relationship was identified between high cervical tumor location and disease recurrence (p = 0.021). CONCLUSIONS: While en bloc resection is appropriate and feasible for tumors in the sacral spine, the cervical region poses a significant technical challenge and is associated with increased postoperative morbidity. Radical resection may allow for achievement of negative operative margins and, along with sparing postoperative morbidity following resection of cervical chordomas, maintaining a similar rate of recurrence when compared with en bloc resection while preserving quality of life.

Mapping scoping reviews in neurosurgery: a scoping review protocol.

INTRODUCTION: The realm of neurosurgery is currently witnessing a surge in primary research, underscoring the importance of adopting evidence-based approaches. Scoping reviews, as a type of evidence synthesis, offer a broad perspective and have become increasingly vital for managing the ever-expanding body of research in swiftly evolving fields. Recent research has indicated a rising prevalence of scoping reviews in healthcare literature. In this context, the concept of a 'review of scoping reviews' has emerged as a means to offer a higher level synthesis of insights. However, the field of neurosurgery appears to lack a comprehensive integration of scoping reviews. Therefore, the objective of this scoping review is to identify and evaluate the extent of scoping reviews within neurosurgery, pinpointing research gaps and methodological issues to enhance evidence-based practices in this dynamic discipline. METHODS: The method framework of Arksey and O'Malley will be used to conduct the scoping review. A thorough literature search will be performed on Medline, Scopus and Web of Science to find eligible studies using the keywords related to neurosurgery, scoping review and its variants. Two reviewers will independently revise all of the full-text articles, extract data and evaluate the study extent. A narrative overview of the findings from included studies will be given. ETHICS AND DISSEMINATION: This review will involve secondary analysis of published literature, and therefore ethics approval is not required. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist will be used to guide translation of findings. Results will be disseminated through peer-reviewed journals and presented in conferences via abstract and presentation.