The relation of perceptual factors and speed of handwriting to spelling ability.

Thesis (Ed.M.)--Boston Universit

Endothelial nitric oxide synthase polymorphism (-786T-\u3eC) and increased risk of angiographic vasospasm after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE: Vasospasm after aneurysmal subarachnoid hemorrhage (SAH) remains a leading cause of death and disability after aneurysm rupture. Decreased availability of nitric oxide (NO) may be crucial in its pathogenesis. We hypothesized that endothelial NO synthase (eNOS) polymorphisms may determine susceptibility to vasospasm in SAH patients. METHODS: We conducted a prospective cohort study of SAH patients and determined vasospasm by cerebral angiography. We genotyped 3 eNOS polymorphisms: an intron 4 variable-number tandem-repeat, a promoter single-nucleotide polymorphism (-786T--\u3eC SNP), and a coding SNP in exon 7 (894G--\u3eT encoding E298D). Using multivariable logistic regression, we quantified the association of eNOS polymorphisms in patients with vasospasm confirmed by cerebral angiography. RESULTS: For the eNOS promoter -786T--\u3eC SNP, the presence of the CC genotype compared with any T genotype (CT or TT) was associated with increased odds of vasospasm (odds ratio=2.97, 95% CI=1.32 to 6.67, P=0.008). No association with vasospasm was observed for the eNOS 894G--\u3eT or variable-number tandem-repeat polymorphisms. CONCLUSIONS: These findings suggest that genetic variation influencing NO regulation contributes to the risk of angiographic vasospasm in patients with SAH. The specific role of the promoter SNP (-786T--\u3eC) may determine the effect of NO regulated by this pathway, distinct from other known eNOS polymorphisms

Racial/ethnic differences in longitudinal risk of intracranial hemorrhage in brain arteriovenous malformation patients

BACKGROUND AND PURPOSE - Race/ethnicity is associated with overall incidence of intracranial hemorrhage (ICH), but its impact in patients with brain arteriovenous malformation is unknown. We evaluated whether race/ethnicity was a risk factor for ICH in the natural course in a large, multiethnic cohort of patients with brain arteriovenous malformation followed longitudinally. METHODS - Data were collected prospectively for patients with brain arteriovenous malformation evaluated at the University of California, San Francisco (n=436) and retrospectively through databases and chart review in the 20 hospitals of the Kaiser Permanente Medical Care Program (n=1028). Multivariate Cox regression was performed to assess the influence of race/ethnicity on subsequent ICH, adjusting for risk factors. Cases were censored at first treatment, loss to follow-up, or death. RESULTS - Average follow up was 4.7±8.0 years for Kaiser Permanente Medical Care Program patients and 2.8±7.3 years for University of California, San Francisco patients with no difference in time to ICH between cohorts (log rank P=0.57). The annualized 5-year ICH rate was 2.1% (3.7% for ruptured at presentation; 1.4% for unruptured). Initial ICH presentation (hazard ratio: 3.0, 95% CI: 1.9 to 4.9, P\u3c0.001) and Hispanic race/ethnicity (hazard ratio: 1.9, 95% CI: 1.1 to 3.3, P=0.02) were independent predictors of ICH, adjusting for age, gender, cohort, and a cohort-age interaction. The ICH risk for Hispanics versus whites increased to 3.1 (95% CI: 1.3 to 7.4, P=0.013) after further adjusting for arteriovenous malformation size and deep venous drainage in a subset of cases with complete data. Similar trends were observed for blacks (hazard ratio: 2.1, 95% CI: 0.9 to 4.8, P=0.09) and Asians (hazard ratio: 2.4, 95% CI: 0.8 to 7.1, P=0.11), although nonsignificant. CONCLUSIONS - This study reports the first description of race/ethnic differences in brain arteriovenous malformation, with Hispanics at an increased risk of subsequent ICH compared with whites. © 2007 American Heart Association, Inc

The effect of preoperative embolization and flow dynamics on resection of brain arteriovenous malformations.

ObjectivePreoperative embolization of brain arteriovenous malformations (AVMs) is performed to facilitate resection, although its impact on surgical performance has not been clearly defined. The authors tested for associations between embolization and surgical performance metrics.MethodsThe authors analyzed AVM cases resected by one neurosurgeon from 2006 to 2017. They tested whether cases with and without embolization differed from one another with respect to patient and AVM characteristics using t-tests for continuous variables and Fisher's exact tests for categorical variables. They used simple and multivariable regression models to test whether surgical outcomes (blood loss, resection time, surgical clip usage, and modified Rankin Scale [mRS] score) were associated with embolization. Additional regression analyses integrated the peak arterial afferent contrast normalized for the size of the region of interest (Cmax/ROI) into models as an additional predictor.ResultsThe authors included 319 patients, of whom 151 (47%) had preoperative embolization. Embolized AVMs tended to be larger (38% with diameter > 3 cm vs 19%, p = 0.001), less likely to have hemorrhaged (48% vs 63%, p = 0.013), or be diffuse (19% vs 29%, p = 0.045). Embolized AVMs were more likely to have both superficial and deep venous drainage and less likely to have exclusively deep drainage (32% vs 17% and 12% vs 23%, respectively; p = 0.002). In multivariable analysis, embolization was not a significant predictor of blood loss or mRS score changes, but did predict longer operating times (+29 minutes, 95% CI 2-56 minutes; p = 0.034) and increased clip usage (OR 2.61, 95% CI 1.45-4.71; p = 0.001). Cmax/ROI was not a significant predictor, although cases with large Cmax/ROI tended to have longer procedure times (+25 minutes per doubling of Cmax/ROI, 95% CI 0-50 minutes; p = 0.051).ConclusionsIn this series, preoperative embolization was associated with longer median resection times and had no association with intraoperative blood loss or mRS score changes

The effect of preoperative embolization and flow dynamics on resection of brain arteriovenous malformations

Objective: Preoperative embolization of brain arteriovenous malformations (AVMs) is performed to facilitate resection, although its impact on surgical performance has not been clearly defined. The authors tested for associations between embolization and surgical performance metrics. Methods: The authors analyzed AVM cases resected by one neurosurgeon from 2006 to 2017. They tested whether cases with and without embolization differed from one another with respect to patient and AVM characteristics using ttests for continuous variables and Fisher\u27s exact tests for categorical variables. They used simple and multivariable regression models to test whether surgical outcomes (blood loss, resection time, surgical clip usage, and modified Rankin Scale [mRS] score) were associated with embolization. Additional regression analyses integrated the peak arterial afferent contrast normalized for the size of the region of interest (Cmax/ROI) into models as an additional predictor. Results: The authors included 319 patients, of whom 151 (47%) had preoperative embolization. Embolized AVMs tended to be larger (38% with diameter \u3e 3 cm vs 19%, p = 0.001), less likely to have hemorrhaged (48% vs 63%, p = 0.013), or be diffuse (19% vs 29%, p = 0.045). Embolized AVMs were more likely to have both superficial and deep venous drainage and less likely to have exclusively deep drainage (32% vs 17% and 12% vs 23%, respectively; p = 0.002). In multivariable analysis, embolization was not a significant predictor of blood loss or mRS score changes, but did predict longer operating times (+29 minutes, 95% CI 2-56 minutes; p = 0.034) and increased clip usage (OR 2.61, 95% CI 1.45-4.71; p = 0.001). Cmax/ROI was not a significant predictor, although cases with large Cmax/ROI tended to have longer procedure times (+25 minutes per doubling of Cmax/ROI, 95% CI 0-50 minutes; p = 0.051). Conclusions: In this series, preoperative embolization was associated with longer median resection times and had no association with intraoperative blood loss or mRS score changes

Brain Arteriovenous Malformation Recurrence After Apparent Microsurgical Cure: Increased Risk in Children Who Present With Arteriovenous Malformation Rupture.

Background and purposeDo children have an increased risk for brain arteriovenous malformation (AVM) recurrence compared with adults and does this risk vary depending on initial presentation with AVM rupture?MethodsWe retrospectively studied 115 patients initially presenting with brain AVM under age 25 years who underwent complete surgical resection of the AVM as documented by digital subtraction angiography (DSA) and had delayed follow-up DSA to evaluate for AVM recurrence after apparent initial cure.ResultsThe mean time from baseline DSA to follow-up DSA was 2.3 years, ranging from 0 to 15 years. Twelve patients (10.4% of the 115 patient cohort and 16.7% of 72 patients with hemorrhage at initial presentation) demonstrated AVM recurrence on follow-up DSA. All patients with recurrence initially presented with intracranial hemorrhage, and intracranial hemorrhage was a significant predictor of recurrence (log rank P=0.037). Among patients with initial hemorrhage, the 5-year recurrence rate was 17.8% (95% CI, 8.3%-35.7%). All recurrences occurred in patients who were children at the time of their initial presentation; the oldest was 15 years of age at the time of initial AVM surgery. The 5-year recurrence rate for children (0-18 years of age) with an initial presentation of hemorrhage was 21.4% (95% CI, 10.1%-41.9%). Using Cox regression, we found the risk of AVM recurrence decreased by 14% per each year increase in age at the time of initial surgical resection (hazard ratio=0.86 [95% CI, 0.75-0.99]; P=0.031).ConclusionsThere is a high rate of recurrence of apparently cured brain AVMs in children who initially present with AVM rupture. Imaging follow-up is warranted to prevent re-rupture

Brain Arteriovenous Malformation Recurrence After Apparent Microsurgical Cure: Increased Risk in Children Who Present With Arteriovenous Malformation Rupture

BACKGROUND AND PURPOSE: Do children have an increased risk for brain arteriovenous malformation (AVM) recurrence compared with adults and does this risk vary depending on initial presentation with AVM rupture? METHODS: We retrospectively studied 115 patients initially presenting with brain AVM under age 25 years who underwent complete surgical resection of the AVM as documented by digital subtraction angiography (DSA) and had delayed follow-up DSA to evaluate for AVM recurrence after apparent initial cure. RESULTS: The mean time from baseline DSA to follow-up DSA was 2.3 years, ranging from 0 to 15 years. Twelve patients (10.4% of the 115 patient cohort and 16.7% of 72 patients with hemorrhage at initial presentation) demonstrated AVM recurrence on follow-up DSA. All patients with recurrence initially presented with intracranial hemorrhage, and intracranial hemorrhage was a significant predictor of recurrence (log rank =0.037). Among patients with initial hemorrhage, the 5-year recurrence rate was 17.8% (95% CI, 8.3%-35.7%). All recurrences occurred in patients who were children at the time of their initial presentation; the oldest was 15 years of age at the time of initial AVM surgery. The 5-year recurrence rate for children (0-18 years of age) with an initial presentation of hemorrhage was 21.4% (95% CI, 10.1%-41.9%). Using Cox regression, we found the risk of AVM recurrence decreased by 14% per each year increase in age at the time of initial surgical resection (hazard ratio=0.86 [95% CI, 0.75-0.99]; =0.031). CONCLUSIONS: There is a high rate of recurrence of apparently cured brain AVMs in children who initially present with AVM rupture. Imaging follow-up is warranted to prevent re-rupture