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A 7-Year Experience in Microsurgical Treatment of Unruptured Intracranial Aneurysms in Older Patients
No full textBACKGROUND AND OBJECTIVES: Controversy exists regarding whether to treat unruptured intracranial aneurysms (UIAs) in older patients. This study analyzes modern outcomes among older patients who underwent microsurgical treatment for UIA. METHODS: Patients treated at a large quaternary center for UIA from January 1, 2014, to December 31, 2020, were retrospectively reviewed. Only patients with a modified Rankin Scale (mRS) score of ≤2 at admission were included. The primary outcome analyzed was mRS score at the 1-year neurological examination; poor neurological outcome was defined as an mRS score of \u3e2. Older patients were defined as \u3e 65 years of age. RESULTS: A total of 390 patients were treated during the 7-year study, of whom 132 (34%) were \u3e 65 years old, with a mean (SD) age of 71 (4) years. There was no significant difference between the cohorts regarding neurological outcomes (mRS score \u3e2) at 1-year follow-up (older vs younger, 14/132 [11%] vs 24/258 [9.3%], P = .82). In older patients, the univariate analysis showed that significant risk factors for poor neurological outcomes were diabetes, high Charlson Comorbidity Index, aneurysm calcification, multiple aneurysms treated, de novo formation or growth of an aneurysm, and higher aspect ratios. On multivariable logistic regression analysis, only diabetes (odds ratio 19.1, 95% CI 1.98-389, P = .02) and de novo formation or growth of an aneurysm (odds ratio 12.7, 95% CI 1.65-169, P = .02) were found to be predictors of a poor neurological outcome. CONCLUSION: Microsurgical treatment of older patients with UIAs is associated with favorable 1-year neurological outcomes comparable with those in younger patients. Diabetes and de novo formation or growth of an aneurysm were associated with poor neurological outcomes in the older cohort
A General Framework for Characterizing Inaccuracy in Stereotactic Systems
No full textBACKGROUND AND OBJECTIVES: Identifying and characterizing sources of targeting error in stereotactic procedures is essential to maximizing accuracy, potentially improving surgical outcomes. We aim to describe a generic framework which characterizes sources of stereotactic inaccuracy. METHODS: We assembled a list of stereotactic systems: ROSA, Neuromate, Mazor Renaissance, ExcelsiusGPS, Cirq, STarFix (FHC), Nexframe, ClearPoint, CRW, and Leksell. We searched the literature for qualitative and quantitative work identifying and quantifying potential sources of inaccuracy and describing each system\u27s implementation using Standards for Reporting Qualitative Research guidelines. Our literature search spanned 1969 to 2024, and various studies were included, with formats ranging from phantom studies to systematic reviews. Keyword searches were conducted, and the details about each system were used to create a framework for identifying and describing the unique targeting error profile of each system. RESULTS: We describe and illustrate the details of various sources of stereotactic inaccuracies and generate a framework to unify these sources into a single framework. This framework entails 5 domains: imaging, registration, mechanical accuracy, target planning and adjustment, and trajectory planning and adjustment. This framework was applied to 10 stereotactic systems. CONCLUSION: This framework provides a rubric to analyze the sources of error for any stereotactic system. Illustrations allow the reader to understand sources of error conceptually so that they may apply them to their practice
A taxonomy for cerebellar cavernous malformations: subtypes of cerebellar lesions
No full textOBJECTIVE: An anatomical taxonomy has been established to guide surgical approach selection for resecting brainstem and deep and superficial cerebral cavernous malformations (CMs). The authors propose a novel taxonomy for cerebellar CMs, introduce 6 distinct neuroanatomical subtypes, and assess their clinical outcomes. METHODS: This bi-institutional, 2-surgeon cohort study included 143 cerebellar CMs that were microsurgically treated over a 25-year period. The proposed taxonomy classifies cerebellar CMs into 6 subtypes on the basis of anatomical location as identified on preoperative MR imaging. Neurological outcomes were assessed using the modified Rankin Scale (mRS), and outcomes were compared among the subtypes, with favorable outcomes defined as mRS scores ≤ 2. RESULTS: A total of 143 cerebellar CMs were resected in 140 patients. The mean (SD) age was 42.3 (15.2) years; 86 (60%) of the cerebellar CMs were in women, and 57 (40%) were in men. Cerebellar subtypes were suboccipital (17%, 25/143); tentorial (9%, 13/143); petrosal (43%, 62/143); vermian (13%, 18/143); tonsillar (2%, 3/143); and deep nuclear (15%, 22/143). Overall, 78 of 143 (55%) cerebellar CMs presenting to a cerebellar surface were resected without tissue transgression, and the remaining CMs (65/143, 45%) required translobular or transsulcal approaches. Complete resection was achieved in 134 of 143 cases (94%). Favorable outcomes were achieved in 91% (129/141) of cases with follow-up at a mean (SD) follow-up duration of 37.4 (53.8) months. Relative outcomes were unchanged or improved relative to the preoperative baseline in 93% (131/141) of cases with follow-up, without differences between subtypes. CONCLUSIONS: Most cerebellar CMs are convexity lesions that do not require deep dissection. However, transsulcal and fissural approaches are used for those beneath the cerebellar surface to minimize tissue transgression and preserve associated function. Complete resection without any new deficit is accomplished in most patients. The proposed taxonomy for cerebellar CMs (suboccipital, tentorial, petrosal, vermian, tonsillar, and deep nuclear) guides the selection of craniotomy and approach to enhance patient safety and optimize neurological outcomes
Sustained diabetes remission induced by FGF1 involves a shift in transcriptionally distinct AgRP neuron subpopulations
No full textIn rodent models of type 2 diabetes, a single intracerebroventricular (icv) injection of fibroblast growth factor 1 (FGF1) induces sustained remission of hyperglycemia. Overactive agouti-related peptide (AgRP) neurons, located in the hypothalamic arcuate nucleus, are a hallmark of diabetic states, and their long-term inhibition has been linked to FGF1\u27s antidiabetic effects. To investigate the underlying mechanism(s), we performed single-nucleus RNA sequencing of the mediobasal hypothalamus at Days 5 and 14 post-injection in wild-type and diabetic (Lep) mice treated with FGF1 or vehicle. We found that AgRP neurons from Lep mice form a transcriptionally distinct, hyperactive subpopulation. By Day 5, icv FGF1 induced a subset of these neurons to shift toward a less active, wild-type-like state, characterized by reduced activity-linked gene expression that persisted through Day 14. Spatial transcriptomics revealed that this FGF1-responsive AgRP subset is positioned dorsally within the arcuate nucleus. The transcriptional shift was accompanied by increased transcriptional processes indicative of GABAergic signaling, axonogenesis, and astrocyte-AgRP and oligodendrocyte-AgRP interactions. These glial inputs involve astrocytic neurexins and the perineuronal net (PNN) component phosphacan, suggesting both intrinsic and extrinsic mechanisms underlie FGF1-induced AgRP silencing. Combined with evidence that FGF1 increases assembly in the arcuate nucleus, our findings reveal a cell-type-specific model for how FGF1 elicits long-term reprogramming of hypothalamic circuits to achieve diabetes remission
C2-P2 Bypass: Technical Assessment of Petrous Carotid Artery to Posterior Cerebral Artery Interpositional Bypass Through the Combined Transcochlear-Subtemporal Approach as a Part of Microsurgical Treatment for Dolichoectatic Vertebrobasilar Artery Aneurysms
No full textBACKGROUND AND OBJECTIVES: Managing dolichoectatic vertebrobasilar artery aneurysms requires a multifaceted approach. Revascularization of the posterior circulation with a high-flow bypass is part of the flow reversal paradigm. Performing a robust high-flow bypass and addressing the aneurysm through the same approach smooths the operative intervention. This study assessed the anatomic feasibility of accessing the basilar trunk and aneurysm simultaneously to revascularize the posterior circulation using a petrous internal carotid artery (pICA)-posterior cerebral artery (PCA) interpositional bypass through a complete petrosectomy. METHODS: Six embalmed cadaveric heads (12 sides) underwent a combined extended transcochlear-subtemporal approach to expose the pICA and P2 PCA. A pICA (side-to-end) graft (end-to-side) PCA bypass was attempted. The lengths of the vessels relevant to the bypass and the graft length were measured. RESULTS: The bypass was successfully completed in all specimens. The mean exposed lengths of the pICA and PCA were 21.3 and 20.0 mm, respectively. The mean length of the perforator-free zone on PCA was 11.2 mm. The mean length of the interposition graft was 36.6 mm. CONCLUSION: The transcochlear approach can be used to expose the pICA as a donor for a high-flow bypass to the PCA as part of the treatment paradigm for dolichoectatic vertebrobasilar artery aneurysms. Careful patient selection and extensive knowledge of skull base anatomy are mandatory for this strategy
Occipital Artery to a3 Anterior Inferior Cerebellar Artery Bypass With Distal Occlusion of an Intrameatal a2 Fusiform Aneurysm
No full textPrinciples of Stereotactic Surgery
No full textBACKGROUND AND OBJECTIVES: Stereotactic procedures are used to manage a diverse set of patients across a variety of clinical contexts. The stereotactic devices and software used in these procedures vary between surgeons, but the fundamental principles that constitute safe and accurate execution do not. The aim of this work is to describe these principles to equip readers with a generalizable knowledge base to execute and understand stereotactic procedures. METHODS: A combination of a review of the literature and empirical experience from several experienced surgeons led to the creation of this work. Thus, this work is descriptive and qualitative by nature, and the literature is used to support instead of generate the ideas of this framework. RESULTS: The principles detailed in this work are categorized based on 5 clinical domains: imaging, registration, mechanical accuracy, target planning and adjustment, and trajectory planning and adjustment. Illustrations and tables are used throughout to convey the concepts in an efficient manner. CONCLUSION: Stereotactic procedures are complex, requiring a thorough understanding of each step of the workflow. The concepts described in this work enable functional neurosurgeons with the fundamental knowledge necessary to provide optimal patient care
Safety of argatroban to address heparin hypersensitivity in open and interventional carotid procedures
No full textBACKGROUND: Heparin-induced thrombocytopenia or heparin-induced hypersensitivity reactions pose a challenge for periprocedural anticoagulation. Direct thrombin inhibitors are an alternative anticoagulant; however, limited literature is available regarding argatroban use in neurovascular procedures. CASE DESCRIPTION: We describe a patient with symptomatic carotid stenosis undergoing angiography and stent placement with an attempted argatroban loading bolus. Stenting was aborted because of plaque morphology, and therapeutic anticoagulation was not reached. The patient underwent carotid endarterectomy with a higher-dose argatroban administration protocol given the previous subtherapeutic anticoagulation during angiography. Argatroban bolus (150 µg/kg) and maintenance infusion (5 µg/kg/min) with argatroban irrigation (0.5 mg/mL, 250 mL total prepared) were used without complication. CONCLUSION: We reviewed the safety of argatroban in reports from eight institutions, including intraoperative use for eight patients and periprocedural use for 178 patients. Reports demonstrated no argatroban-related complications
The Neurosurgeon\u27s Role in Brain Health Diplomacy: The Next Step for Global Neurosurgery
No full textValidation of automated detection of REM sleep without atonia using in-laboratory and in-home recordings.
No full textSTUDY OBJECTIVES: To evaluate the concordance between visual scoring and automated detection of rapid eye movement sleep without atonia (RSWA) and the validity and reliability of in-home automated-RSWA detection in patients with rapid eye movement sleep behavior disorder (RBD) and a control group.
METHODS: Sleep Profiler signals were acquired during simultaneous in-laboratory polysomnography in 24 isolated patients with RBD. Chin and arm RSWA measures visually scored by an expert sleep technologist were compared to algorithms designed to automate RSWA detection. In a second cohort, the accuracy of automated-RSWA detection for discriminating between RBD and control group (n = 21 and 42, respectively) was assessed in multinight in-home recordings.
RESULTS: For the in-laboratory studies, agreement between visual and auto-scored RSWA from the chin and arm were excellent, with intraclass correlations of 0.89 and 0.95, respectively, and substantial, based on Kappa scores of 0.68 and 0.74, respectively. For classification of patients with iRBD vs controls, specificities derived from auto-detected RSWA densities obtained from in-home recordings were 0.88 for the chin, 0.93 for the arm, and 0.90 for the chin or arm, while the sensitivities were 0.81, 0.81, and 0.86, respectively. The night-to-night consistencies of the respective auto-detected RSWA densities were good based on intraclass correlations of 0.81, 0.79, and 0.84, however some night-to-night disagreements in abnormal RSWA detection were observed.
CONCLUSIONS: When compared to expert visual RSWA scoring, automated RSWA detection demonstrates promise for detection of RBD. The night-to-night reliability of chin- and arm-RSWA densities acquired in-home were equivalent.
CITATION: Levendowski DJ, Chahine LM, Lewis SJG, et al. Validation of automated detection of REM sleep without atonia using in-laboratory and in-home recordings