Assessment of morphology and hemodynamics in a surgically clipped neck of a cerebral aneurysm: illustrative case.

BACKGROUND: Silent magnetic resonance angiography reduces metal artifacts, enabling clear visualization of the clipped neck following surgical clipping of cerebral aneurysms. This study aimed to delineate the morphology of the clipped neck complex in cerebral aneurysms using three-dimensional (3D) multifusion imaging of silent magnetic resonance angiography and fast spin echo magnetic resonance cisternography. Additionally, computational fluid dynamics analysis was utilized to evaluate the hemodynamics of the parent vessel at the clipped neck, allowing for a detailed assessment of hemodynamics at the clipped neck. OBSERVATIONS: The 3D multifusion image enabled visualization of the orientation and shape of the clip within the clipped neck complex, alongside the morphology of the parent vessel. In the hemodynamic analysis of the parent vessel at the clipped neck, areas of high-intensity magnitude of wall shear stress (WSSm) variation corresponding to the clip's contour, along with significant vector of wall shear stress (WSSv) variation related to vector directionality, were visualized in 3D. The intentional residual neck, coated with muscle grafts, was depicted as an area with low WSSm variation values and high WSSv variation values. LESSONS: Three-dimensional multifusion imaging, along with computational fluid dynamics analysis of the parent vessels, facilitated both the morphological and hemodynamic visualization and assessment of the clipped neck complex following neck clipping surgery for cerebral aneurysms. https://thejns.org/doi/10.3171/CASE24194.

Evaluation of the shrinkage process of a neck remnant after stent-coil treatment of a cerebral aneurysm using silent magnetic resonance angiography and computational fluid dynamics analysis: illustrative case.

BACKGROUND: Silent magnetic resonance angiography (MRA) mitigates metal artifacts, facilitating clear visualization of neck remnants after stent and coil embolization of cerebral aneurysms. This study aims to scrutinize hemodynamics at the neck remnant by employing silent MRA and computational fluid dynamics. OBSERVATIONS: The authors longitudinally tracked images of a partially thrombosed anterior communicating artery aneurysm's neck remnant, which had been treated with stent-assisted coil embolization, using silent MRA over a decade. Computational fluid dynamics delineated the neck remnant's reduction process, evaluating hemodynamic parameters such as flow rate, wall shear stress magnitude and vector, and streamlines. The neck remnant exhibited diminishing surface area, volume, neck size, dome depth, and aspect ratio. Its reduction correlated with a decline in the flow rate ratio of the remnant dome to the inflow parent artery. Analysis delineated regions within the contracting neck remnant characterized by consistently low average wall shear stress magnitude and variation, accompanied by notable variations in wall shear stress vector directionality. LESSONS: Evaluation of neck remnants after stent-coil embolization is possible through silent MRA and computational fluid dynamics. Predicting the neck remnant reduction may be achievable through hemodynamic parameter analysis.

Assessment of Mild Cognitive Impairment Using CogEvo: A Computerized Cognitive Function Assessment Tool.

INTRODUCTION/OBJECTIVES: To assess the utility of the computerized cognitive function assessment tool, CogEvo, as a screening tool for mild cognitive impairment in primary care, we explored the relationship between CogEvo performance, age, and the severity of cognitive dysfunction evaluated by the Mini-Mental State Examination (MMSE). METHODS: The observational cross-sectional study included 209 individuals' data (mean age 79.4 ± 8.9 years). We conducted a correlation analysis between CogEvo and MMSE scores, compared the performance among the 3 cognitive function groups (MMSE ≥ 28 group; MMSE24-27 group; MMSE ≤ 23 group) using the MMSE cut-off, and evaluated CogEvo's predictive accuracy for cognitive dysfunction through ROC analysis. RESULTS: Both total CogEvo and MMSE scores significantly decreased with age. A significant positive correlation was observed between total CogEvo and MMSE scores, but a ceiling effect was detected in MMSE performance. Significant differences were observed in the total CogEvo score, including orientation and spatial cognitive function scores, among the 3 groups. CogEvo showed no educational bias. ROC analyses indicated moderate discrimination between the MMSE ≥ 28 group and the MMSE24-27 and MMSE ≤ 23 groups. CONCLUSIONS: The computer-administered CogEvo has the advantage of not exhibiting ceiling effects or educational bias like the MMSE, and was found to be able to detect age-related cognitive decline and impairment.

Validity and reliability of a computerized cognitive function evaluation battery (CogEvo) as a screening tool.

Aim: The aim of this study was to determine the validity and reliability of cognitive function evaluation battery, CogEvo, a recently developed computerized cognitive function evaluation battery, as a screening tool for decreased cognitive function. Methods: The study sample comprised 123 (age: 57-97 years) community-dwelling elderly people. They were required to perform five CogEvo tasks and complete two questions-based neuropsychological tests, including the Mini-Mental State Examination, so that the correlations could be analyzed. The validity and reliability of CogEvo were examined using factor analysis, MacDonald's omega reliability coefficient, logistic regression analysis, and receiver operating characteristic curve analysis. Results: Exploratory factor analysis revealed the orientation/spatial cognitive function (orientation and spatial cognition) and attention/executive function (attention, memory, and execution) factors. Structural validity was supported by confirmatory factor analysis. All two-factor-based subtasks showed adequate internal consistency (MacDonald's omega ≥0.6). The total CogEvo score and two-factor scores were significantly correlated with neuropsychological test results. Based on the total CogEvo score, the cognitively normal and cognitive decline groups were identified by receiver operating characteristic curve analysis with a moderate predictive performance. The cognitive decline group was well identified using the orientation/spatial cognitive function factor. Conclusions: CogEvo is a valid and reliable screening tool for cognitive function evaluation. It proved useful in the early identification of cognitive decline in our study sample.

Computational Fluid Dynamics Analysis of Trigeminal Neuralgia Associated with the Vertebral Artery: A Report of Two Cases.

Trigeminal neuralgia is a nerve disorder that causes unilateral severe facial pain. The clinical features of trigeminal neuralgia are agonizing, paroxysmal, anticipated in one or more divisions of the trigeminal nerve, with repetitive bursts of a few seconds, exacerbated by cutaneous stimuli. Microvascular decompression is proven effective, resulting in a positive outcome. Here, we report two cases of trigeminal neuralgia associated with the vertebral artery, who underwent endoscopic microvascular decompression. This case report aims to show the benefit of computational fluid dynamics evaluation of the neurovascular contact and its effect on change in wall shear stress magnitude of the offending vertebral artery after surgical management with microvascular decompression.