Sex-dependent characteristics and outcomes after clipping of unruptured intracranial aneurysms: a multicenter propensity score-matched study.

OBJECTIVE: Disparities in the epidemiology and growth rates of aneurysms between the sexes are known. However, little is known about sex-dependent outcomes after microsurgical clipping of unruptured intracranial aneurysms (UIAs). The aim of this study was to examine sex differences in characteristics and outcomes after microsurgical clipping of UIAs and to perform a propensity score-matched analysis using an international multicenter cohort. METHODS: This retrospective cohort study involved the participation of 15 centers spanning four continents. It included adult patients who underwent clipping of UIAs between January 2016 and December 2020. Patients were stratified according to their sex and analyzed for differences in morbidities and aneurysm characteristics. Based on this stratification, female patients were matched to male patients in a 1:1 ratio with a caliper width of 0.1 using propensity score matching. Endpoints included postoperative complications, neurological performance, and aneurysm occlusion at discharge and 24 months after clip placement. RESULTS: A total of 2245 patients with a mean age of 57.3 (range 20-87) years were included. Of these patients, 1675 (74.6%) were female. Female patients were significantly older (mean 57.6 vs 56.4 years, p = 0.03) but had fewer comorbidities. Aneurysms of the internal carotid artery (7.1% vs 4.2%), posterior communicating artery (6.9% vs 1.9%), and ophthalmic artery (6.0% vs 2.8%) were more commonly treated surgically in females, while clipping of aneurysms of the anterior communicating artery was more frequent in males (17.0% vs 25.3%; all p < 0.001). After propensity score matching, female patients were found to have had significantly fewer pulmonary complications (1.4% vs 4.2%, p = 0.01). However, general morbidity (24.5% vs 25.2%, p = 0.72) and mortality (0.5% vs 1.1%, p = 0.34), as well as neurological performance (p = 0.58), were comparable at discharge in both sexes. Lastly, rates of aneurysm occlusion at the time of discharge (95.5% vs 94.9%, p = 0.71) and 24 months after surgery (93.8% vs 96.1%, p = 0.22) did not significantly differ between male and female patients. CONCLUSIONS: Despite overall differences between male and female patients in demographics, comorbidities, and treated aneurysm location, sex did not relevantly affect surgical performance or perioperative complication rates.

Evaluation of the structural integrity of different spinal cord tracts with magnetization transfer ratio in degenerative cervical myelopathy.

PURPOSE: Degenerative cervical myelopathy (DCM) is a common cause of spinal cord dysfunction. In this study, we explored the potential of magnetization transfer ratio (MTR) for evaluating the structural integrity of spinal cord tracts in patients with clinically significant DCM. METHODS: Fifty-three patients with DCM and 41 patients with cervical radiculopathy were evaluated using high-resolution cervical spinal cord magnetic resonance imaging (MRI), which included the magnetization transfer technique. MRI data were analyzed with the Spinal Cord Toolbox (v5.5); MTR values in each spinal tract were calculated and compared between groups after correction for patient age and sex. Correlations between MTR values and patients' clinical disability rate were also evaluated. RESULTS: A statistically significant reduction in the average MTR of the spinal cord white matter, as well as the MTR of the ventral columns and lateral funiculi, was revealed in the DCM group (adjusted p < 0.01 for all comparisons). Furthermore, reductions in MTR values in the fasciculus cuneatus, spinocerebellar, rubrospinal, and reticulospinal tracts were found in patients with DCM (adjusted p < 0.01 for all comparisons). Positive correlations between the JOA score and the MTR within the ventral columns of the spinal cord (R = 0.38, adjusted p < 0.05) and the ventral spinocerebellar tract (R = 0.41, adjusted p < 0.05) were revealed. CONCLUSION: The findings of our study indicate that demyelination in patients with DCM primarily affects the spinal tracts of the extrapyramidal system, and the extent of these changes is related to the severity of the condition.

Utilizing the amide proton transfer technique to characterize diffuse gliomas based on the WHO 2021 classification of CNS tumors.

PURPOSE: Diffuse gliomas present a significant challenge for healthcare systems globally. While brain MRI plays a vital role in diagnosis, prognosis, and treatment monitoring, accurately characterizing gliomas using conventional MRI techniques alone is challenging. In this study, we explored the potential of utilizing the amide proton transfer (APT) technique to predict tumor grade and type based on the WHO 2021 Classification of CNS Tumors. METHODS: Forty-two adult patients with histopathologically confirmed brain gliomas were included in the study. They underwent 3T MRI imaging, which involved APT sequence. Multinomial and binary logistic regression models were employed to classify patients into clinically relevant groups based on MRI findings and demographic variables. RESULTS: We found that the best model for tumor grade classification included patient age along with APT values. The highest sensitivity (88%) was observed for Grade 4 tumors, while Grade 3 tumors showed the highest specificity (79%). For tumor type classification, our model incorporated four predictors: APT values, patient's age, necrosis, and the presence of hemorrhage. The glioblastoma group had the highest sensitivity and specificity (87%), whereas balanced accuracy was the lowest for astrocytomas (0.73). CONCLUSION: The APT technique shows great potential for noninvasive evaluation of diffuse gliomas. The changes in the classification of gliomas as per the WHO 2021 version of the CNS Tumor Classification did not affect its usefulness in predicting tumor grade or type.

Microsurgical Clipping of Unruptured Anterior Circulation Aneurysms-A Global Multicenter Investigation of Perioperative Outcomes.

BACKGROUND AND OBJECTIVES: Microsurgical aneurysm repair by clipping continues to be highly important despite increasing endovascular treatment options, especially because of inferior occlusion rates. This study aimed to present current global microsurgical treatment practices and to identify risk factors for complications and neurological deterioration after clipping of unruptured anterior circulation aneurysms. METHODS: Fifteen centers from 4 continents participated in this retrospective cohort study. Consecutive patients who underwent elective microsurgical clipping of untreated unruptured intracranial aneurysm between January 2016 and December 2020 were included. Posterior circulation aneurysms were excluded. Outcome parameters were postsurgical complications and neurological deterioration (defined as decline on the modified Rankin Scale) at discharge and during follow-up. Multivariate regression analyses were performed adjusting for all described patient characteristics. RESULTS: Among a total of 2192 patients with anterior circulation aneurysm, complete occlusion of the treated aneurysm was achieved in 2089 (95.3%) patients at discharge. The occlusion rate remained stable (94.7%) during follow-up. Regression analysis identified hypertension (P < .02), aneurysm diameter (P < .001), neck diameter (P < .05), calcification (P < .01), and morphology (P = .002) as preexisting risk factors for postsurgical complications and neurological deterioration at discharge. Furthermore, intraoperative aneurysm rupture (odds ratio 2.863 [CI 1.606-5.104]; P < .01) and simultaneous clipping of more than 1 aneurysm (odds ratio 1.738 [CI 1.186-2.545]; P < .01) were shown to be associated with an increased risk of postsurgical complications. Yet, none of the surgical-related parameters had an impact on neurological deterioration. Analyzing volume-outcome relationship revealed comparable complication rates (P = .61) among all 15 participating centers. CONCLUSION: Our international, multicenter analysis presents current microsurgical treatment practices in patients with anterior circulation aneurysms and identifies preexisting and surgery-related risk factors for postoperative complications and neurological deterioration. These findings may assist in decision-making for the optimal therapeutic regimen of unruptured anterior circulation aneurysms.

Global Outcomes for Microsurgical Clipping of Unruptured Intracranial Aneurysms: A Benchmark Analysis of 2245 Cases.

BACKGROUND AND OBJECTIVES: Benchmarks represent the best possible outcome and help to improve outcomes for surgical procedures. However, global thresholds mirroring an optimal and reachable outcome for microsurgical clipping of unruptured intracranial aneurysms (UIA) are not available. This study aimed to define standardized outcome benchmarks in patients who underwent clipping of UIA. METHODS: A total of 2245 microsurgically treated UIA from 15 centers were analyzed. Patients were categorized into low- ("benchmark") and high-risk ("nonbenchmark") patients based on known factors affecting outcome. The benchmark was defined as the 75th percentile of all centers' median scores for a given outcome. Benchmark outcomes included intraoperative (eg, duration of surgery, blood transfusion), postoperative (eg, reoperation, neurological status), and aneurysm-related factors (eg, aneurysm occlusion). Benchmark cutoffs for aneurysms of the anterior communicating/anterior cerebral artery, middle cerebral artery, and posterior communicating artery were determined separately. RESULTS: Of the 2245 cases, 852 (37.9%) patients formed the benchmark cohort. Most operations were performed for middle cerebral artery aneurysms (53.6%), followed by anterior communicating and anterior cerebral artery aneurysms (25.2%). Based on the results of the benchmark cohort, the following benchmark cutoffs were established: favorable neurological outcome (modified Rankin scale ≤2) ≥95.9%, postoperative complication rate ≤20.7%, length of postoperative stay ≤7.7 days, asymptomatic stroke ≤3.6%, surgical site infection ≤2.7%, cerebral vasospasm ≤2.5%, new motor deficit ≤5.9%, aneurysm closure rate ≥97.1%, and at 1-year follow-up: aneurysm closure rate ≥98.0%. At 24 months, benchmark patients had a better score on the modified Rankin scale than nonbenchmark patients. CONCLUSION: This study presents internationally applicable benchmarks for clinically relevant outcomes after microsurgical clipping of UIA. These benchmark cutoffs can serve as reference values for other centers, patient registries, and for comparing the benefit of other interventions or novel surgical techniques.

Application of the T1w/T2w mapping technique for spinal cord assessment in patients with degenerative cervical myelopathy.

STUDY DESIGN: Retrospective case-control study. OBJECTIVES: To investigate signal changes on T1w/T2w signal intensity ratio maps within cervical cord in patients with degenerative cervical myelopathy (DCM). SETTING: Novosibirsk Neurosurgery Center, Russia. METHODS: A total of 261 patients with DCM and 42 age- and sex-matched healthy controls were evaluated using the T1w/T2w mapping method and spinal cord automatic morphometry. The T1w/T2w signal intensity ratio, which reflects white matter integrity, and the spinal cord cross-sectional area (CSA) were calculated and compared between the patients and the controls. In patients with DCM, the correlations between these parameters and neurological scores were also evaluated. RESULTS: The regional T1w/T2w ratio values from the cervical spinal cord at the level of maximal compression in patients with DCM were significantly lower than those in healthy controls (p < 0.001), as were the regional CSA values (p < 0.001). There was a positive correlation between the regional values of the T1w/T2w ratio and the values of the CSA at the level of maximal spinal cord compression. CONCLUSIONS: T1w/T2w mapping revealed that spinal cord tissue damage exists at the level of maximal compression in patients with DCM in association with spinal cord atrophy according to automatic morphometry. These changes were correlated with each other.

Diffusion tensor imaging reveals distributed white matter abnormalities in primary trigeminal neuralgia: Tract-based spatial statistics study.

BACKGROUND: Primary trigeminal neuralgia (PTN) is a prevalent chronic pain disorder whose pathogenesis is not limited to the trigeminal system. Despite the significant advances in uncovering underlying mechanisms, there is a paucity of comprehensive and consistent data regarding the role of white matter throughout the entire brain in PTN. METHODS: We performed a prospective case-control study. Sixty patients with PTN and 28 age- and sex-matched healthy controls were evaluated using diffusion tensor imaging (DTI). A tract-based spatial statistical approach was performed to investigate white matter impairment in patients with PTN with several metrics, including fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD). Additionally, ROI-based analysis was performed for each white matter tract to compare FA values between groups with correction for patient age and sex. Correlations between DTI data and nerve root compression severity, as well as pain severity, were also evaluated in patients with PTN. RESULTS: Our analysis demonstrated a widespread and symmetrical reduction in FA values among TN patients when compared to the control group (p < 0.05). Specifically, this FA decrease was predominantly observed in regions such as the corona radiata, internal capsule, optic radiation, and thalami, as well as structures within the posterior fossa, notably the cerebellar peduncles. No statistically significant differences were found between patients and the control group during the MD, AD and RD map analyses. ROI-based analysis did not reveal statistically significant changes in FA values in white matter tracts (p > 0.05 in all comparisons, FDR-corrected); however, there were trends towards FA value decreases in the internal capsule (p = 0.08, FDR-corrected) and inferior fronto-occipital fasciculus (p = 0.09, FDR-corrected). CONCLUSIONS: Our findings indicate the presence of microstructural abnormalities in white matter among individuals with primary trigeminal neuralgia, which may potentially play a role in the development and progression of the condition.

Endoscopic endonasal repair of temporal lobe meningoencephalocele in the lateral recess of the sphenoid sinus, complicated by intracerebral hematoma: illustrative case.

BACKGROUND: Anomalies in the anatomical structure of the nasal cavity and paranasal sinuses often serve as a potential cause of spontaneous cerebrospinal fluid (CSF) leakage and may result in the development of a meningoencephalocele. In this report, the authors present a case of surgically treated intrasphenoidal meningoencephalocele attributed to the persistence of the lateral craniopharyngeal canal, which was further complicated by the occurrence of an intracerebral hematoma. OBSERVATIONS: A temporal lobe meningoencephalocele located in the lateral recess of the sphenoid sinus was successfully managed using endoscopic endonasal transpterygoid repair (EETR). However, an intracerebral hematoma developed after resection of the meningoencephalocele, necessitating additional surgical interventions. Despite this complication, the patient exhibited a favorable clinical outcome after the surgical interventions. LESSONS: This case highlights the potential risk of intracerebral hematoma associated with EETR of a lateral sphenoid sinus meningoencephalocele. A thorough examination of magnetic resonance imaging scans, especially identifying vascular structures, is crucial during surgical planning. This knowledge can help to prevent the occurrence of complications, including intracerebral hematoma.

Open and Percutaneous Trigeminal Nucleotractotomy: A Case Series and Literature Review.

INTRODUCTION: Nucleotractotomy is an efficient surgical technique that provides a high pain relief rate for specific clinical indications. There are two main approaches for performing this operation: an open and percutaneous technique. METHODS: In the Federal Center of Neurosurgery (Novosibirsk, Russia) from 2016 to 2022, 13 trigeminal nucleotractotomies (7 open and 6 percutaneous) were performed in 12 patients (5 women and 7 men). The indications for surgery were deafferentation pain and chronic drug-resistant pain syndrome caused by malignancy in the facial region. A neurological examination was done on each patient 1 day before the surgery, right after the surgery, and at the follow-up (examinations were done after 1, 6, and 12 months, or when the patient independently applied to our hospital). In the early postoperative period, patients underwent brain MRI. RESULTS: The average pain intensity score before nucleotractotomy on the 11-point (0-10) visual analog scale (VAS) was 9.3. The effectiveness of open interventions was somewhat higher; the average VAS score in the early postoperative period for the open technique was 1.57, in the group of patients who underwent percutaneous nucleotractotomy were 2.66. Complete regression of the pain syndrome was achieved in 6 patients; in 5 patients, the pain in the face decreased by more than 50%. One case had an unsatisfactory outcome. In the open-surgery group in the early postoperative period, according to MRI, the average length of the visualized area of signal change was longer (21.5 mm, the average diameter was 3.75 mm) than in a percutaneous nucleotractotomy group (16 mm, the average diameter was 3.75 mm). During the postoperative period (average follow-up 40 months), the pain recurred in 3 patients (30%): 2 patients after percutaneous nucleotractotomy (3 and 18 months after surgery) and in 1 patient 4 months after the open surgery. The mean VAS score at the last follow-up was 2.6. CONCLUSION: Trigeminal nucleotractotomy is an effective approach to the treatment of intractable facial pain. Our experience suggests this technique is highly effective in patients with drug-resistant pain caused by craniofacial tumors and deafferentation conditions after treating trigeminal neuralgia.

Crooke Cell Adenoma Confers Poorer Endocrinological Outcomes Compared with Corticotroph Adenoma: Results of a Multicenter, International Analysis.

BACKGROUND: Crooke cell adenomas (CCAs) are a rare, aggressive subset of secretory pituitary corticotroph adenomas (sCTAs) found in 5%-10% of patients with Cushing disease. Multiple studies support worse outcomes in CCAs but are limited by small sample size and single-institution databases. We compared outcomes in CCA and sCTA using a multicenter, international retrospective database of high-volume skull base centers. METHODS: Patients surgically treated for pituitary adenoma from January 2017 through December 2020 were included. RESULTS: Among 2826 patients from 12 international centers, 20 patients with CCA and 480 patients with sCTA were identified. No difference in baseline demographics, tumor characteristics, or postoperative complications was seen. Microsurgical approaches (60% CCA vs. 62.3% sCTA) were most common. Gross total resection was higher in CCA patients (100% vs. 83%, P = 0.05). Among patients with gross total resection according to intraoperative findings, fewer CCA patients had postoperative hormone normalization of pituitary function (50% vs. 77.8%, P < 0.01) and remission of hypersecretion by 3-6 months (75% vs. 84.3%, P < 0.01). This was the case despite CCA having better local control rates (100% vs. 96%, P < 0.01) and fewer patients with remnant on magnetic resonance imaging (0% vs. 7.2%, P < 0.01). A systematic literature review of 35 studies reporting on various treatment strategies reiterated the high rate of residual tumor, persistent hypercortisolism, and tumor-related mortality in CCA patients. CONCLUSIONS: This modern, multicenter series of patients with CCA reflects their poor prognosis and reduced postsurgical hormonal normalization. Further work is necessary to better understand the pathophysiology of CCA to devise more targeted treatment approaches.

Defining benchmark outcomes for transsphenoidal surgery of pituitary adenomas: a multicenter analysis.

IMPORTANCE: Benchmarks aid in improve outcomes for surgical procedures. However, best achievable results that have been validated internationally for transsphenoidal surgery (TS) are not available. OBJECTIVE: We aimed to establish standardized outcome benchmarks for TS of pituitary adenomas. DESIGN: A total of 2685 transsphenoidal tumor resections from 9 expert centers in 3 continents were analyzed. SETTING: Patients were risk stratified, and the median values of each center's outcomes were established. The benchmark was defined as the 75th percentile of all median values for a particular outcome. The postoperative benchmark outcomes included surgical factors, endocrinology-specific values, and neurology-specific values. RESULTS: Of 2685 patients, 1149 (42.8%) defined the low-risk benchmark cohort. Within these benchmark cases, 831 (72.3%) patients underwent microscopic TS, and 308 (26.8%) patients underwent endoscopic endonasal resection. Of all tumors, 799 (29.8%) cases invaded the cavernous sinus. The postoperative complication rate was 19.6% with mortality between 0.0% and 0.8%. Benchmark cutoffs were ≤2.9% for reoperation rate, ≤1.9% for cerebrospinal fluid leak requiring intervention, and ≤15.5% for transient diabetes insipidus. At 6 months, benchmark cutoffs were calculated as follows: readmission rate: ≤6.9%, new hypopituitarism ≤6.0%, and tumor remnant ≤19.2%. CONCLUSIONS: This analysis defines benchmark values for TS targeting morbidity and mortality and represents the best outcomes in the best patients in expert centers. These cutoffs can be used to assess different centers, patient populations, and novel surgical techniques. It should be noted that the benchmark values may influence each other and must be evaluated in their own context.

Brainstem and subcortical regions volume loss in patients with degenerative cervical myelopathy and its association with spinal cord compression severity.

BACKGROUND: In recent years, structural and functional reorganization of the brain and changes in brainstem structural connectivity have been shown in patients with degenerative cervical myelopathy (DCM). We hypothesized that volume loss in the basal ganglia, thalami, and brainstem structures exists and is associated with spinal cord compression severity in patients with DCM. METHODS: Forty-seven patients with DCM and 25 patients with cervical radiculopathy were evaluated using cervical spinal cord and brain magnetic resonance imaging (MRI). Brainstem structures, basal ganglia, and thalami volumes were evaluated with FreeSurfer and compared between groups with correction for individual intracranial volume, as well as patient age and sex. Additionally, spinal cord MRI data were analysed with the Spinal Cord Toolbox, and cross-sectional area (CSA) and fractional anisotropy (FA) values were calculated. Correlations between MR-morphometry data and spinal cord structural changes, as well as disease duration, were also evaluated in patients with DCM. RESULTS: A statistically significant reduction in the volume of the whole brainstem was revealed in the DCM group compared to the radiculopathy group (p < 0.01, FDR-corrected). Additionally, reductions in medulla oblongata, pons and midbrain volumes were found in patients with DCM (p < 0.01, p < 0.01 and p < 0.05, respectively, FDR-corrected). Additionally, a trend in the loss of volume of the left putamen was found (p = 0.087, FDR-corrected). Furthermore, medulla oblongata volume was correlated with spinal cord compression severity (R = 0.54, adjusted p < 0.001) and white matter damage (R = 0.46, adjusted p < 0.05) in patients with DCM. Negative correlations between the duration of the disease and the severity of spinal cord compression (R = -0.42, adjusted p < 0.05) and white matter damage (R = -0.49, adjusted p < 0.05) were also revealed, as well as a trend toward a negative association between the duration of the disease and the volume of the medulla oblongata (R = -0.35; adjusted p < 0.1). CONCLUSIONS: We revealed a reduction in the volume of brainstem structures in patients with DCM compared to patients with radiculopathy. Moreover, we found that these changes are associated with cord compression severity.

Brain but not serum BDNF levels are associated with structural alterations in the hippocampal regions in patients with drug-resistant mesial temporal lobe epilepsy.

Mesial temporal lobe epilepsy is the most common type of focal epilepsy, imposing a significant burden on the health care system worldwide. Approximately one-third of patients with this disease who do not adequately respond to pharmacotherapy are considered drug-resistant subjects. Despite having some clues of how such epileptic activity and resistance to therapy emerge, coming mainly from preclinical models, we still witness a scarcity of human data. To narrow this gap, in this study, we aimed to estimate the relationship between hippocampal and serum levels of brain-derived neurotrophic factor (BDNF), one of the main and most widely studied neurotrophins, and hippocampal subfield volumes in patients with drug-resistant mesial temporal epilepsy undergoing neurosurgical treatment. We found that hippocampal (but not serum) BDNF levels were negatively correlated with the contralateral volumes of the CA1 and CA4 subfields, presubiculum, subiculum, dentate gyrus, and molecular layer of the hippocampus. Taken together, these findings are generally in accordance with existing data, arguing for a proepileptic nature of BDNF effects in the hippocampus and related brain structures.

Cottonoid Retention After Craniotomy: Causes and Ways to Avoid It.

Nonabsorbable surgical material left in an surgical wound may cause early postoperative infections and specific types of granulomas; thus, it represents a dangerous complication in neurosurgery. The authors have analyzed their experience and present four cases of cottonoid retention after intracranial tumor resection. During 5-year period (from 2013 until 2017), the incidence of such an undesirable event after craniotomy for various indications was 0.07%. It was not related to the professional experience of the operating neurosurgeon, but cases of deep-seated lesions, the presence of brain edema or excessive bleeding of neoplastic or peritumoral tissue, prolonged surgeries, use of cottonoids without marking thread, and inadequate counting of disposable surgical materials at the end of the procedure may increase the risk of this complication. In all of the presented cases, the retained cottonoids were clearly seen on postoperative computed tomography because of the presence of radiopaque identifiers. All of the patients underwent an urgent reoperation for removal of the foreign body within 24 h after completion of the primary surgery, and they subsequently experienced an uneventful postoperative course without any complications. Well-coordinated work of the surgical team-in particular, appropriate communication between the surgeon and the circulating nurse during counting of surgical materials at the end of the procedure-is absolutely necessary for prevention of cottonoid retention after brain surgery.

Report of the third international Siberian neurosurgical conference (Sibneuro 22): Scientific and professional exchange in the heart of Siberia.

We present a summary of the recently held Third International Siberian Neurosurgical Conference (Sibneuro 22). Professional education, scientific exchange, and social interactions are essential in neurosurgical practice. In addition to the main program of the Congress, there were two practical pre-meeting courses: on aneurysm clipping and on intraoperative neuromonitoring. In addition, there was a 1-day seminar focusing on a role of laboratory diagnostics in neurosurgical practice. Within the framework of the Siberian Congress, there was a session devoted to inventions in neurosurgery, a rare subject of discussion at neurosurgical events. Our educational event is very important for the Siberian neurosurgery. Neurosurgeons of Siberia are a part of the world neurosurgical family. We not only try providing high-quality neurosurgical care to patients but also maintaining the academic level of education and scientific activity. The next - fourth - Siberian Neurosurgical Congress will take place in July 2024 in Irkutsk.

White and Gray Matter Perfusion in Children with Moyamoya Angiopathy after Revascularization Surgery.

INTRODUCTION: Surgical revascularization is very effective in patients with moyamoya angiopathy (MMA) and leads to improvements in cortical perfusion parameters. However, changes in white matter hemodynamics are still underestimated. To date, only a few studies have examined brain perfusion changes within deep white matter after bypass surgery in patients with MMA. METHODS: Ten children with MMA were evaluated using the CT perfusion technique before and after revascularization surgery. Brain perfusion parameters within gray and white matter were compared before and after surgery. The correlations between the perfusion parameters before surgery and the Suzuki stage, as well as between the perfusion parameters and the cognitive scores, were also evaluated. RESULTS: Brain perfusion parameters improved significantly in both gray matter (predominantly due to cerebral blood flow within the anterior circulation, p < 0.01) and white matter (predominantly due to cerebral blood volume within the semiovale centrum, p < 0.001). We revealed that the pattern of improvement in perfusion in white matter differed from the pattern of improvement in perfusion in gray matter. Significant correlations were revealed between the Suzuki stage before surgery and the perfusion parameters within the posterior cerebral artery circulation (adjusted p < 0.05). There were also significant correlations between cognitive scores and brain perfusion parameters in gray matter and white matter (adjusted p < 0.05). CONCLUSIONS: The perfusion parameters of gray matter and white matter in the brain improve differently after bypass surgery in patients with MMA. Different hemodynamics within these compartments could explain this.

A Multicenter, Propensity Score-Matched Assessment of Endoscopic Versus Microscopic Approaches in the Management of Pituitary Adenomas.

BACKGROUND AND OBJECTIVES: There is considerable controversy as to which of the 2 operating modalities (microsurgical or endoscopic transnasal surgery) currently used to resect pituitary adenomas (PAs) is the safest and most effective intervention. We compared rates of clinical outcomes of patients with PAs who underwent resection by either microsurgical or endoscopic transnasal surgery. METHODS: To independently assess the outcomes of each modality type, we sought to isolate endoscopic and microscopic PA surgeries with a 1:1 tight-caliper (0.01) propensity score-matched analysis using a multicenter, neurosurgery-specific database. Surgeries were performed between 2017 and 2020, with data collected retrospectively from 12 international institutions on 4 continents. Matching was based on age, previous neurological deficit, American Society of Anesthesiologists (ASA) score, tumor functionality, tumor size, and Knosp score. Univariate and multivariate analyses were performed. RESULTS: Among a pool of 2826 patients, propensity score matching resulted in 600 patients from 9 surgery centers being analyzed. Multivariate analysis showed that microscopic surgery had a 1.91 odds ratio (OR) ( P = .03) of gross total resection (GTR) and shorter operative duration ( P < .01). However, microscopic surgery also had a 7.82 OR ( P < .01) for intensive care unit stay, 2.08 OR ( P < .01) for intraoperative cerebrospinal fluid (CSF) leak, 2.47 OR ( P = .02) for postoperative syndrome of inappropriate antidiuretic hormone secretion (SIADH), and was an independent predictor for longer postoperative stay (ß = 2.01, P < .01). Overall, no differences in postoperative complications or 3- to 6-month outcomes were seen by surgical approach. CONCLUSION: Our international, multicenter matched analysis suggests microscopic approaches for pituitary tumor resection may offer better GTR rates, albeit with increased intensive care unit stay, CSF leak, SIADH, and hospital utilization. Better prospective studies can further validate these findings as matching patients for outcome analysis remains challenging. These results may provide insight into surgical benchmarks at different centers, offer room for further registry studies, and identify best practices.

Assessment of normal myelination in infants and young children using the T1w/T2w mapping technique.

Background: White matter myelination is a crucial process of CNS maturation. The purpose of this study was to validate the T1w/T2w mapping technique for brain myelination assessment in infants and young children. Methods: Ninety-four patients (0-23 months of age) without structural abnormalities on brain MRI were evaluated by using the T1w/T2w mapping method. The T1w/T2w signal intensity ratio, which reflects white matter integrity and the degree of myelination, was calculated in various brain regions. We performed a Pearson correlation analysis, a LOESS regression analysis, and a 2nd order polynomial regression analysis to describe the relationships between the regional metrics and the age of the patients (in months). Results: T1w/T2w ratio values rapidly increased in the first 6-9 months of life and then slowed thereafter. The T1w/T2w mapping technique emphasized the contrast between myelinated and less myelinated structures in all age groups, which resulted in better visualization. There were strong positive correlations between the T1w/T2w ratio values from the majority of white matter ROIs and the subjects' age (R = 0.7-0.9, p < 0.001). Within all of the analyzed regions, there were non-linear relationships between age and T1/T2 ratio values that varied by anatomical and functional location. Regions such as the splenium and the genu of the corpus callosum showed the highest R2 values, thus indicating less scattering of data and a better fit to the model. Conclusion: The T1w/T2w mapping technique may enhance our diagnostic ability to assess myelination patterns in the brains of infants and young children.

Concordance between the In Vivo Content of Neurospecific Proteins (BDNF, NSE, VILIP-1, S100B) in the Hippocampus and Blood in Patients with Epilepsy.

The identification of reliable brain-specific biomarkers in periphery contributes to better understanding of normal neurophysiology and neuropsychiatric diseases. The neurospecific proteins BDNF, NSE, VILIP-1, and S100B play an important role in the pathogenesis of neuropsychiatric disorders, including epilepsy. This study aimed to assess the correspondence of the expression of BDNF, NSE, VILIP-1, and S100B in the blood (serum and peripheral blood mononuclear cells (PBMCs)) to the in vivo hippocampal levels of subjects with drug-resistant epilepsy who underwent neurosurgery (N = 44) using multiplex solid-phase analysis, ELISA, and immunohistochemical methods, as well as to analyze the correlations and associations of the blood and hippocampal levels of these proteins with clinical parameters. We first studied the concordance between in vivo brain and blood levels of BDNF, NSE, VILIP-1, and S100B in epileptic patients. A positive correlation for NSE between hippocampal and PBMC levels was revealed. NSE levels in PBMCs were also significantly correlated with average seizure duration. BDNF levels in PBMCs were associated with seizure frequency and hippocampal sclerosis. Thus, NSE and BDNF levels in PBMCs may have potential as clinically significant biomarkers. Significant correlations between the levels of the neurospecific proteins studied herein suggest interactions between BDNF, NSE, VILIP-1, and S100B in the pathophysiology of epilepsy.