Clinical and Technical Outcomes of Intracranial-Intracranial Bypass for Treating Complex Intracranial Aneurysms: An Analysis of 255 Patients.

BACKGROUND: Despite the recent increase in publications centered on intracranial-intracranial (IC-IC) bypasses for complex aneurysms, there is no systematic evidence regarding its outcomes. The purpose was to assess the outcomes of patients subjected to IC-IC bypass for aneurysms. METHODS: Following PRISMA, a systematic review was conducted. Criteria for inclusion entailed studies with a cohort of at least four patients having undergone IC-IC bypass for aneurysms, detailing at least one outcome, such as patency, clinical outcomes, complications, and procedure-related mortality. When the study included patients who had undergone extracranial-intracranial (EC-IC) bypass, the authors extracted the patency and clinical data to juxtapose it with the results of IC-IC. RESULTS: Of the 2,509 shortlisted studies, 22 met our inclusion criteria, encompassing 255 patients and 263 IC-IC bypass procedures. The IC-IC bypass procedure exhibited a patency rate of 93% (95% CI: 89%-95%). The patency rate of IC-IC and EC-IC bypasses did not significantly differ (OR = 0.60 (95% CI: 0.18 - 1.96). Concerning clinical outcomes, 91% of the IC-IC patients had positive results (95% CI: 85% - 97%), with no significant disparity between the IC-IC and EC-IC groups (OR = 1.29 (95% CI: 0.43 - 3.88). After analysis, the complication rate was 11% (95% CI: 5% - 18%). Procedure-related mortality was 1% (95% CI: 0% - 4 %). CONCLUSION: IC-IC bypass is valuable for the treatment of complex intracranial aneurysms, boasting high patency and positive clinical outcomes. Complications are unusual, and procedure-related mortality is minimal. Comparing IC-IC and EC-IC led to no significant differences.

Enhancing the quality of evidence, comparability, and reproducibility in brain arteriovenous malformations treated with open surgery research: a systematic review and proposal of a reporting guideline for surgical and clinical outcomes.

Brain Arteriovenous Malformations (bAVMs) are rare but high-risk developmental anomalies of the vascular system. Microsurgery through craniotomy is believed to be the mainstay standard treatment for many grades of bAVMs. However, a significant challenge emerges in the existing body of clinical studies on open surgery for bAVMs: the lack of reproducibility and comparability. This study aims to assess the quality of studies reporting clinical and surgical outcomes for bAVMs treated by open surgery and develop a reporting guideline checklist focusing on essential elements to ensure comparability and reproducibility. This is a systematic literature review that followed the PRISMA guidelines with the search in Medline, Embase, and Web of Science databases, for studies published between January 1, 2018, and December 1, 2023. Included studies were scrutinized focusing on seven domains: (1) Assessment of How Studies Reported on the Baseline Characteristics of the Patient Sample; (2) Assessment and reporting on bAVMs grading, anatomical characteristics, and radiological aspects; (3) Angioarchitecture Assessment and Reporting; (4) Reporting on Pivotal Concepts Definitions; (5) Reporting on Neurosurgeon(s) and Staff Characteristics; (6) Reporting on Surgical Details; (7) Assessing and Reporting Clinical and Surgical Outcomes and AEs. A total of 47 studies comprising 5,884 patients were included. The scrutiny of the studies identified that the current literature in bAVM open surgery is deficient in many aspects, ranging from fundamental pieces of information of methodology to baseline characteristics of included patients and data reporting. Included studies demonstrated a lack of reproducibility that hinders building cumulative evidence. A bAVM Open Surgery Reporting Guideline with 65 items distributed across eight domains was developed and is proposed in this study aiming to address these shortcomings. This systematic review identified that the available literature regarding microsurgery for bAVM treatment, particularly in studies reporting clinical and surgical outcomes, lacks rigorous scientific methodology and quality in reporting. The proposed bAVM Open Surgery Reporting Guideline covers all essential aspects and is a potential solution to address these shortcomings and increase transparency, comparability, and reproducibility in this scenario. This proposal aims to advance the level of evidence and enhance knowledge regarding the Open Surgery treatment for bAVMs.

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.

Partial Labyrinth Removal Restricted to the Superior Semicircular Canal in Focal Combined Transpetrosal Approach: Description and Illustrative Cases.

BACKGROUND AND OBJECTIVES: The labyrinthine structures obstruct the surgical view of the deep petroclival region in the transpetrosal approach. Historically, labyrinthectomy and removal of all 3 semicircular canals, with resultant deafness, was used in patients with ipsilateral functional hearing deficits to improve access. The advent and systematization of superior and posterior semicircular canal removal (transcrusal approach) with good rates of hearing preservation has allowed a redefinition of the possibility of partial labyrinthectomy in patients without previous hearing deficits. The present manuscript is intended to describe a technical refinement of partial labyrinthectomy during focal combined petrosectomy, offering a customization of the approach through the selective removal of the superior semicircular canal for specific types of tumors. METHODS: The use of the technique is demonstrated through surgical drawings, pictures, and videos. The rationale to indicate this new approach is discussed based on clinical cases. RESULTS: Three illustrative clinical cases (petroclival meningiomas) are demonstrated. Functional hearing on the approach side has been preserved in all of them. CONCLUSION: The focal combined transpetrosal approach associated with the superior semicircular canal resection has been a promising surgical technique in the treatment of selected petroclival tumors. It has the potential to further decrease the risks of postoperative auditory and vestibular dysfunctions associated with labyrinthectomies.

Current State of Brazilian Neurosurgery: Evaluation of Burden of Care and Case Volume.

BACKGROUND: Low- and middle-income countries (LMICs) bear a heavier burden of neurosurgical diseases than high-income countries. Brazil, a growing middle-income country, holds promise as a health care market. However, there exists a lack of information to characterize the state of neurosurgical practice and access to care in Brazil. This study aimed to characterize neurosurgical practice in Brazil and identify barriers to care. METHODS: A collaborative survey was developed with Brazilian neurosurgeons and distributed by the Brazilian Society of Neurosurgery. The survey gathered demographic information, practice characteristics, case volume, referral patterns, income sources, and assessed barriers using a Likert scale. Descriptive statistics were employed for data analysis. RESULTS: One-hundred and forty-nine neurosurgeons participated (response rate: 17.5%), representing various states in Brazil. Neurosurgeons practiced in more than 4 different hospital systems on average, with most consultations and procedures occurring in public hospitals. Common procedures included tumor surgeries, general neurosurgery, spine surgeries, trauma surgeries, and hydrocephalus management. Equipment shortage and systemic issues were identified as major barriers to care. CONCLUSIONS: Neurosurgical practice in Brazil exhibits diverse age distribution, widespread distribution across states, and involvement in both public and private hospitals. Survey insights shed light on neurosurgical workload and neurosurgical practice characterization. Lack of equipment and inadequate postoperative resources pose significant barriers to care. The findings highlight the need for investments in equipment, critical care facilities, and improved health care system coordination to enhance access to neurosurgical care in Brazil.

Comparative Anatomic Study Between Intradural Suboccipital Retrosigmoid and Extradural Transzygomatic Middle Fossa Approaches to Expose the Trigeminal Nerve.

BACKGROUND: Meckel cave tumors are relatively rare, especially trigeminal nerve (TN) schwannomas. These tumors frequently project through the trigeminal pore, occupying the middle and posterior fossae. The most used routes to this region are the suboccipital retrosigmoid intradural approach (SORSA) and the transzygomatic middle fossa approach (TZMFA). Both approaches allow further exposure by adding intraoperative techniques, such as removing the suprameatal tubercle (retrosigmoid intradural suprameatal approach [RISA]) and the petrous apex (TZMFA-PA), respectively. This study aims to understand how TN exposure differs between both surgical approaches and how it increases by adding specific surgical maneuvers to these techniques. METHODS: Five formalin-fixed adult cadaver heads were submitted to high-resolution computed tomography and their images were loaded into the neuronavigation device. Anatomic key points were defined along the outline of the TN, and their three-dimensional spatial locations were collected following each surgical approach. This process allowed the calculation of the TN exposed area obtained through each technique. RESULTS: The mean areas of exposure of the TN were 125.9 mm2 with SORSA and 208.9 mm2 with RISA, which represents an additional mean gain of 61.92% (P = 0.047). Using TZMFA, a mean exposure of 419.24 mm2 was obtained. When TZMFA-PA was used, the mean exposed area was 486.03 mm2, representing a mean gain in the exposure area of 16.81% (P = 0.072). CONCLUSIONS: Our study suggests that TZMFA allows better exposure of TN ganglionic and postganglionic segments, and the removal of the PA adds the preganglionic segment visualization, although with less TN exposed area compared with RISA. With SORSA, the additional suprameatal tubercle removal shows the trigeminal pore and the medial margin of the central portion of the TN ganglionic segment, making it possible to expose the mouth of the Meckel cave and part of its contents.

Minipterional Approach for Middle Fossa Skull Base Lesions: Technical Note.

Surgical access to the middle fossa can be technically challenging. As neurosurgery evolves to minimally invasive approaches, the objective of this study is to demonstrate the extension of the Minipterional approach to access the middle fossa. We present a new surgical approach to the middle fossa for the treatment of secondary trigeminal neuralgia. Three cases are reported to illustrate the following techniques: a patient with petrotentorial meningioma and trigeminal neuralgia, a patient with an arachnoid cyst compressing the fifth nerve, and a patient with a middle cerebral artery aneurysm and a long history of TN (trigeminal neuralgia) refractory to medical and surgical treatments. All three experienced full symptom controls with no permanent neurological deficits. Therefore, the Minipterional technique might represent a feasible, effective, and safe option to treat refractory secondary TN. It also allows approaching these lesions when the posterior fossa approach is compromised by anatomical distortion and enables the simultaneous treatment of secondary trigeminal neuralgia and other lesions, such as aneurysms and meningiomas.

Spheno-orbital meningiomas: Is orbit reconstruction mandatory? Long-term outcomes and exophthalmos improvement.

Background: Meningiomas correspond to one-third of all primary central nervous system tumors. Approximately 9% of them are spheno-orbital meningiomas (SOMs), presenting significant clinical symptoms as visual impairment and orbital esthetics. This article aims to evaluate exophthalmos' improvement in a surgical series without orbital reconstruction. Methods: We consecutively included all patients diagnosed with SOM, admitted to a single institution for 10 years. Surgical resection was the standard of care, associated or not with adjuvant radiation therapy. The radiological investigation included preoperative and postoperative head CT or MRI. We quantified proptosis through imaging. Results: Forty patients composed this series, 87.5% were female. Proptosis was the most common presentation (90%), followed by decreased visual acuity (65%), motility deficit (20%), and headache (20%). Gross total resection was achieved in 65% of the procedures. In late outcomes, 78% of the patients maintained or improved visual acuity and 85% maintained or improved headache. Proptosis significantly improved after surgery and along with the follow-up (P < 0.001). Ten patients were submitted to adjuvant RT, six of them after a subtotal resection. All patients of this subgroup had proptosis. It was observed a higher frequency of worse in visual acuity in patients submitted to RT (71% vs. 28%, P = 0.038). Conclusion: Resection of SOM was sufficient to stop the evolution of visual deficit and allowed the improvement of proptosis. Orbital reconstruction does not seem to be an essential step in reducing enophthalmos.

Corrigendum: Behavioral and Neural Correlates of Cognitive Training and Transfer Effects in Stroke Patients.

[This corrects the article DOI: 10.3389/fneur.2020.01048.].

Peptidomic profiling of cerebrospinal fluid from patients with intracranial saccular aneurysms.

Intracranial saccular aneurysms (ISA) represent 90%-95% of all intracranial aneurysm cases, characterizing abnormal pockets at arterial branch points. Ruptures lead to subarachnoid hemorrhages (SAH) and poor prognoses. We applied mass spectrometry-based peptidomics to investigate the peptidome of twelve cerebrospinal fluid (CSF) samples collected from eleven patients diagnosed with ISA. For peptide profile analyses, participants were classified into: 1) ruptured intracranial saccular aneurysms (RIA), 2) unruptured intracranial saccular aneurysms (UIA), and late-ruptured intracranial saccular aneurysms (LRIA). Altogether, a total of 2199 peptides were detected by both Mascot and Peaks software, from which 484 (22.0%) were unique peptides. All unique peptides presented conserved chains, domains, regions of protein modulation and/or post-translational modification sites related to human diseases. Gene Ontology (GO) analyses of peptide precursor proteins showed that 42% are involved in binding, 56% in cellular anatomical entities, and 39% in intercellular signaling molecules. Unique peptides identified in patients diagnosed with RIA have a larger molecular weight and a distinctive developmental process compared to UIA and LRIA (P ≤ 0.05). Continued investigations will allow the characterization of the biological and clinical significance of the peptides identified in the present study, as well as identify prototypes for peptide-based pharmacological therapies to treat ISA. SIGNIFICANCE.

Behavioral and Neural Correlates of Cognitive Training and Transfer Effects in Stroke Patients.

Stroke lesions are frequently followed by cognitive impairments. Cognitive training is a non-pharmacological intervention that can promote neural compensation mechanisms and strategies to remediate cognitive impairments. The aims of this study were: (1) To investigate the cognitive performance, generalization effects, and neural correlates of semantic organization strategy training (SOST) in patients with chronic left frontoparietal stroke and healthy controls (HC); and (2) to compare the behavioral effects and neural correlates of SOST with an active control psychoeducation intervention (PI). In this randomized controlled study, all participants were randomly allocated into two groups, one group received SOST, and the other received PI intervention. Participants underwent two fMRI sessions, one prior and the other, after intervention. In each fMRI session, images were obtained during memory encoding task using a list of semantically related words. We found improved post-intervention memory performance in participants that received SOST (both patients and controls), indicated by number of words recalled, word clustering scores, and performance in a generalization task. The fMRI analysis revealed negative correlation between task performance and regions of the default-mode network. These results suggest that cognitive training using semantic organization strategy can improve episodic memory performance and promote potential functional neuroplasticity in patients with ischemic stroke lesions. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT03644290.

Brain Abscess and Esophageal Dilatation: Where is the Link? ­ Case Report

Introduction Caustic substance ingestion is a common cause of esophageal stricture in children. The primary treatment is esophageal dilatation. Although it is known that endoscopic esophageal dilatation is a procedure associated with a high rate of bacteremia, current guidelines do not recommend routine throat swab cultures or antibiotic prophylaxis for the general children population. Case Report We describe a case of a 7-year-old boy presenting with refractory headaches who was diagnosed with cranial abscess after multiple esophageal dilatations due to stenosis caused by caustic soda ingestion. The patient was subjected to neurosurgical intervention and intravenous antibiotic treatment for 6 weeks. Streptococcus viridans culture was positive in purulent abscess content. Conclusion We highlight this condition that, although rare, needs immediate diagnosis and proper treatment. We also recommend routine testing of throat swabs and antibiotics prophylaxis to children undergoing esophageal dilatation.