scholarly journals Computer simulation of Cerebral Arteriovenous Malformation—validation analysis of hemodynamics parameters

PeerJ ◽  
2016 ◽  
Vol 5 ◽  
pp. e2724 ◽  
Author(s):  
Y. Kiran Kumar ◽  
Shashi Bhushan Mehta ◽  
Manjunath Ramachandra
Keyword(s):  
Arteriovenous Malformation ◽  
Cross Validation ◽  
Univariate Analysis ◽  
Vessel Diameter ◽  
Cerebral Arteriovenous Malformation ◽  
Mean Flow ◽  
Exponential Regression ◽  
Hemodynamic Assessment ◽  
Clinical Measurements ◽  
The Relationship

ProblemThe purpose of this work is to provide some validation methods for evaluating the hemodynamic assessment of Cerebral Arteriovenous Malformation (CAVM). This article emphasizes the importance of validating noninvasive measurements for CAVM patients, which are designed using lumped models for complex vessel structure.MethodsThe validation of the hemodynamics assessment is based on invasive clinical measurements and cross-validation techniques with the Philips proprietary validated software’s Qflow and 2D Perfursion.ResultsThe modeling results are validated for 30 CAVM patients for 150 vessel locations. Mean flow, diameter, and pressure were compared between modeling results and with clinical/cross validation measurements, using an independent two-tailed Studentttest. Exponential regression analysis was used to assess the relationship between blood flow, vessel diameter, and pressure between them. Univariate analysis is used to assess the relationship between vessel diameter, vessel cross-sectional area, AVM volume, AVM pressure, and AVM flow results were performed with linear or exponential regression.DiscussionModeling results were compared with clinical measurements from vessel locations of cerebral regions. Also, the model is cross validated with Philips proprietary validated software’s Qflow and 2D Perfursion. Our results shows that modeling results and clinical results are nearly matching with a small deviation.ConclusionIn this article, we have validated our modeling results with clinical measurements. The new approach for cross-validation is proposed by demonstrating the accuracy of our results with a validated product in a clinical environment.

E-098 histopathological and hemodynamic assessment of the cerebral arteriovenous malformation nidus

2015 ◽  
Vol 7 (Suppl 1) ◽  
pp. A85.1-A85 ◽  
Author(s):  
S Shakur ◽  
T Valyi-Nagy ◽  
S Amin-Hanjani ◽  
L Ya'qoub ◽  
V Aletich ◽  
...  
Keyword(s):  
Arteriovenous Malformation ◽  
Cerebral Arteriovenous Malformation ◽  
Hemodynamic Assessment

Intracranial Blood Flow Changes After Extracranial Carotid Artery Stenting

Neurosurgery ◽  
2015 ◽  
Vol 76 (3) ◽  
pp. 330-336 ◽  
Author(s):  
Sophia F. Shakur ◽  
Sepideh Amin-Hanjani ◽  
Caroline Bednarski ◽  
Xinjian Du ◽  
Victor A. Aletich ◽  
...  
Keyword(s):  
Blood Flow ◽  
Carotid Artery ◽  
Carotid Artery Stenting ◽  
Internal Carotid ◽  
Univariate Analysis ◽  
Vessel Diameter ◽  
Mean Flow ◽  
Extracranial Carotid Artery ◽  
Flow Changes ◽  
Symptomatic Stenosis

Abstract BACKGROUND: Carotid artery stenting is an endovascular treatment option for patients with extracranial carotid stenosis. However, intracranial blood flow changes following stenting have not been established. OBJECTIVE: To determine the effects of stenting on intracranial blood flow. METHODS: Records of patients who underwent stenting at our institution between 2004 and 2012 and had flow rates obtained pre- and poststenting by the use of quantitative magnetic resonance angiography were retrospectively reviewed. Percentage stenosis, stenosis length, and minimum vessel diameter were measured from cerebral angiography images. RESULTS: Eighteen patients were included. Mean age was 65 years with 67% presenting with symptomatic stenosis. Degree of stenosis ranged from 60% to 90%. Internal carotid artery (ICA) mean flow improved significantly poststenting from 174.9 ± 83.6 mL/min to 250.7 ± 91.2 mL/min (P = .011). Ipsilateral middle cerebral artery (MCA) flow, however, was not significantly altered poststenting (107.8 ± 41.6 mL/min vs 114.3 ± 36.3 mL/min; P = .28). Univariate analysis revealed that improved minimum vessel diameter after stenting, but not percentage stenosis (P = .18) or stenosis length (P = .45), is significantly associated with increased ICA flow (P = .02). However, improved percentage stenosis, stenosis length, minimum vessel diameter, and ICA flow poststenting were not significantly associated with increased MCA flow (P = .64, .38, .13, .37, respectively). CONCLUSION: ICA flow was compromised at baseline, improving 43% on average poststenting. Increased minimum vessel diameter was the factor most significantly associated with increased flow. Conversely, MCA flow was not significantly compromised at baseline nor altered after stenting, suggesting compensatory intracranial collateral supply prestenting that redistributes following ICA revascularization.

Cerebral arteriovenous malformation draining vein stenosis is associated with atherosclerotic risk factors

2017 ◽  
Vol 10 (8) ◽  
pp. 788-790 ◽  
Author(s):  
Nasya Mendoza-Elias ◽  
Sophia F Shakur ◽  
Fady T Charbel ◽  
Ali Alaraj
Keyword(s):  
Risk Factors ◽  
Arteriovenous Malformation ◽  
Chronic Kidney Disease Stage ◽  
Cerebral Arteriovenous Malformation ◽  
Disease Stage ◽  
Venous Outflow ◽  
Venous Stenosis ◽  
Vein Stenosis ◽  
The Relationship ◽  
Atherosclerotic Risk Factors

ObjectiveThe pathogenesis of venous outflow stenosis associated with cerebral arteriovenous malformation (AVM) draining veins is poorly understood. We sought to determine the relationship between venous stenosis and atherosclerotic risk factors.Materials and methodsAll patients with an AVM seen at our institution between 1990 and 2016 were retrospectively reviewed. Patients <18 years of age were excluded. Patients were classified into two groups based on the presence or absence of venous stenosis. Patient charts were reviewed for the following atherosclerotic risk factors: age >50 years, sex, race, hypertension, type 2 diabetes mellitus, hyperlipidemia, coronary artery disease, chronic kidney disease stage III, and cigarette smoking. The relationship between venous stenosis and atherosclerotic risk factors was assessed using univariate and multivariate analyses.Results278 patients were included (mean age 41 years, 55% men). Venous stenosis was present in 87 patients (31% of the cohort). The presence of venous stenosis was significantly associated with age >50 years (P=0.05), hypertension (P=0.05), diabetes (P=0.02), and hyperlipidemia (P=0.001). Multivariate analysis showed that hyperlipidemia (P=0.05) was predictive of draining vein stenosis.ConclusionsVenous stenosis is associated with several atherosclerotic risk factors, suggesting that cerebral AVM venous outflow stenosis occurs by a degenerative process. Additional studies can show whether these modifiable risk factors may be targeted to prevent draining vein stenosis and AVM rupture.

Panic and agoraphobia associated with a cerebral arteriovenous malformation

1993 ◽  
Vol 10 (2) ◽  
pp. 94-96 ◽  
Author(s):  
Christopher B Kelly ◽  
Stephen J Cooper
Keyword(s):  
Arteriovenous Malformation ◽  
Cerebral Arteriovenous Malformation ◽  
The Relationship

AbstractA patient with epilepsy developed panic and agoraphobia. A large right temporo-parietal, arteriovenous malformation was detected. The relationship between these disorders is discussed.

Surgery for Cerebral Arteriovenous Malformation

2015 ◽  
Vol 76 (S 02) ◽  
Author(s):  
Yoko Kato ◽  
Yasuhiro Yamada ◽  
Kei Yamashiro ◽  
Tsukasa Kawase
Keyword(s):  
Arteriovenous Malformation ◽  
Cerebral Arteriovenous Malformation

scholarly journals Correlation between fundus autofluorescence and visual function in patients with cone-rod dystrophy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Satoru Kanda ◽  
Takumi Hara ◽  
Ryosuke Fujino ◽  
Keiko Azuma ◽  
Hirotsugu Soga ◽  
...  
Keyword(s):  
Visual Field ◽  
Significant Relationship ◽  
Fundus Autofluorescence ◽  
Univariate Analysis ◽  
Retrospective Chart Review ◽  
Mean Deviation ◽  
Wide Field ◽  
The Mean ◽  
The Relationship ◽  
Field Imaging

AbstractThis study aimed to investigate the relationship between autofluorescence (AF) signal measured with ultra-wide field imaging and visual functions in patients with cone-rod dystrophy (CORD). A retrospective chart review was performed for CORD patients. We performed the visual field test and fundus autofluorescence (FAF) measurement and visualized retinal structures with optical coherence tomography (OCT) on the same day. Using binarised FAF images, we identified a low FAF area ratio (LFAR: low FAF/30°). Relationships between age and logMAR visual acuity (VA), central retinal thickness (CRT), central choroidal thickness (CCT), mean deviation (MD) value, and LFAR were investigated. Thirty-seven eyes of 21 CORD patients (8 men and 13 women) were enrolled. The mean patient age was 49.8 years. LogMAR VA and MD were 0.52 ± 0.47 and − 17.91 ± 10.59 dB, respectively. There was a significant relationship between logMAR VA and MD (p = 0.001). LogMAR VA significantly correlated with CRT (p = 0.006) but not with other parameters. Conversely, univariate analysis suggested a significant relationship between MD and LFAR (p = 0.001). In the multivariate analysis, LFAR was significantly associated with MD (p = 0.002). In conclusion, it is useful to measure the low FAF area in patients with CORD. The AF measurement reflects the visual field deterioration but not VA in CORD.

scholarly journals Hypogonadism and liver fibrosis in HIV-infected patients

2021 ◽  
Author(s):  
E. Quiros-Roldan ◽  
T. Porcelli ◽  
L. C. Pezzaioli ◽  
M. Degli Antoni ◽  
S. Paghera ◽  
...  
Keyword(s):  
Liver Fibrosis ◽  
Univariate Analysis ◽  
Free Testosterone ◽  
Sex Hormone Binding Globulin ◽  
Total Testosterone ◽  
Cross Sectional ◽  
Pituitary Dysfunction ◽  
Consequent Reduction ◽  
Secondary Hypogonadism ◽  
The Relationship

Abstract Purpose Hypogonadism is frequent in HIV-infected men and might impact on metabolic and sexual health. Low testosterone results from either primary testicular damage, secondary hypothalamic-pituitary dysfunction, or from liver-derived sex-hormone-binding-globulin (SHBG) elevation, with consequent reduction of free testosterone. The relationship between liver fibrosis and hypogonadism in HIV-infected men is unknown. Aim of our study was to determine the prevalence and type of hypogonadism in a cohort of HIV-infected men and its relationship with liver fibrosis. Methods We performed a cross-sectional retrospective study including 107 HIV-infected men (median age 54 years) with hypogonadal symptoms. Based on total testosterone (TT), calculated free testosterone, and luteinizing hormone, five categories were identified: eugonadism, primary, secondary, normogonadotropic and compensated hypogonadism. Estimates of liver fibrosis were performed by aspartate aminotransferase (AST)-to-platelet ratio index (APRI) and Fibrosis-4 (FIB-4) scores. Results Hypogonadism was found in 32/107 patients (30.8%), with normogonadotropic (10/107, 9.3%) and compensated (17/107, 15.8%) being the most frequent forms. Patients with secondary/normogonadotropic hypogonadism had higher body mass index (BMI) (p < 0001). Patients with compensated hypogonadism had longer HIV infection duration (p = 0.031), higher APRI (p = 0.035) and FIB-4 scores (p = 0.008), and higher HCV co-infection. Univariate analysis showed a direct significant correlation between APRI and TT (p = 0.006) and SHBG (p = 0.002), and between FIB-4 and SHBG (p = 0.045). Multivariate analysis showed that SHBG was independently associated with both liver fibrosis scores. Conclusion Overt and compensated hypogonadism are frequently observed among HIV-infected men. Whereas obesity is related to secondary hypogonadism, high SHBG levels, related to liver fibrosis degree and HCV co-infection, are responsible for compensated forms.

scholarly journals The relationship between maximal expiratory pressure values and critical outcomes in mechanically ventilated patients: a post hoc analysis of an observational study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yann Combret ◽  
Guillaume Prieur ◽  
Roger Hilfiker ◽  
Francis-Edouard Gravier ◽  
Pauline Smondack ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Observational Study ◽  
Univariate Analysis ◽  
Premature Death ◽  
Extubation Failure ◽  
Short Term ◽  
Expiratory Muscle ◽  
Maximal Expiratory Pressure ◽  
The Impact ◽  
The Relationship

Abstract Background Little interest has been paid to expiratory muscle strength, and the impact of expiratory muscle weakness on critical outcomes is not known. Very few studies assessed the relationship between maximal expiratory pressure (MEP) and critical outcomes. The aim of this study was to investigate the relationship between MEP and critical outcomes. Methods This work was a secondary analysis of a prospective, observational study of adult patients who required mechanical ventilation for ≥ 24 h in an 18-bed ICU. MEP was assessed before extubation after a successful, spontaneous breathing trial. The relationships between MEP and extubation failure, and short-term (30 days) mortality, were investigated. Univariate logistic regressions were computed to investigate the relationship between MEP values and critical outcomes. Two multivariate analyses, with and without maximal inspiratory pressure (MIP), both adjusted using principal component analysis, were undertaken. Unadjusted and adjusted ROC curves were computed to compare the respective ability of MEP, MIP and the combination of both measures to discriminate patients with and without extubation failure or premature death. Results One hundred and twenty-four patients were included. Median age was 66 years (IQR 18) and median mechanical ventilation duration was 7 days (IQR 6). Extubation failure rate was 15% (18/124 patients) and the rate for 30-day mortality was 11% (14/124 patient). Higher MEP values were significantly associated with a lower risk of extubation failure in the univariate analysis [OR 0.96 95% CI (0.93–0.98)], but not with short-term mortality. MEP was independently linked with extubation failure when MIP was not included in the multivariate model, but not when it was included, despite limited collinearity between these variables. This study was not able to differentiate the respective abilities of MEP, MIP, and their combination to discriminate patients with extubation failure or premature death (adjusted AUC for the combination of MEP and MIP: 0.825 and 0.650 for extubation failure and premature death, respectively). Conclusions MEP is related to extubation failure. But, the results did not support its use as a substitute for MIP, since the relationship between MEP and critical outcomes was no longer significant when MIP was included. The use of MIP and MEP measurements combined did not reach higher discriminative capacities for critical outcomes that MEP or MIP alone. Trial Registration This study was retrospectively registered at https://clinicaltrials.gov/ct2/show/NCT02363231?cond=NCT02363231&draw=2&rank=1 (NCT02363231) in 13 February 2015

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