Search

Your search keyword '"Lawton, Michael T."' showing total 3,693 results
Start Over Author "Lawton, Michael T."
3,693 results on '"Lawton, Michael T."'

1. Association between sociodemographic variables and delayed patient presentation among surgical neuro-oncology patients in Mexico City: a single institution experience

Author

Punchak, Maria A., Alvarez-Castro, Jose Alfonso, Escalante, Jonathan Ramos, Hidalgo, Keren Magaly Aguilar, Zamarripa, Mauricio Macias, Navarrete, Xymena Dominguez, Soto, Fernando Castro, Castellanos, Mackenzie, Moreno-Jiménez, Sergio, Lawton, Michael T., Quinones-Hinojosa, Alfredo, and Mejía Pérez, Sonia Iliana

Published
2024
Full Text
View/download PDF

7. 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

Author

Ferreira, Marcio Y., Mitre, Lucas P., Bishay, Anthony E., Batista, Sávio, Palavani, Lucca B., Oliveira, Leonardo B., Semione, Gabriel, Andreão, Filipi F., Porto Junior, Silvio, Sousa, Marcelo P., Borges, Pedro G. L. B., Camerotte, Raphael, Bertani, Raphael, Lawton, Michael T., and Figueiredo, Eberval G.

Published
2024
Full Text
View/download PDF

11. Comparing Characteristics and Treatment of Brain Vascular Malformations in Children and Adults with HHT

Author

Kilian, Alexandra, Latino, Giuseppe A, White, Andrew J, Ratjen, Felix, McDonald, Jamie, Whitehead, Kevin J, Gossage, James R, Krings, Timo, Lawton, Michael T, Kim, Helen, Faughnan, Marie E, and Group, The Brain Vascular Malformation Consortium HHT Investigator

Subjects
Biomedical and Clinical Sciences, Clinical Sciences, Pediatric Research Initiative, Hematology, Congenital Structural Anomalies, Rare Diseases, Orphan Drug, Prevention, Pediatric, Clinical Research, Brain Disorders, Neurosciences, hereditary hemorrhagic telangiectasia, pediatrics, brain vascular malformation, embolization, gamma knife, surgery, intracranial hemorrhage, screening, Biomedical and clinical sciences
Abstract

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disease characterized by the development of vascular malformations (VMs) in organs such as the brain and lungs, as well as telangiectases on mucosal surfaces. Prophylactic treatment of organ VMs may prevent potential complications, such as hemorrhage. However, brain VM treatment-surgical resection, embolization, and/or radiosurgery-is not recommended for all patients due to the associated risks. Given the scarcity of data regarding HHT-related brain VM presentation and treatment trends in pediatric patients, we aim to describe the clinical presentations and the patterns of treatment of HHT-related brain VMs in a pediatric cohort, and compare pediatric trends to those of adults. Demographic and clinical data were analyzed in 114 pediatric patients with HHT-related brain VMs and compared with a cohort of 253 adult patients enrolled in the multicenter Brain Vascular Malformation Consortium HHT Project. Our data demonstrated that a higher proportion of pediatric patients with HHT-related brain VMs were symptomatic at presentation (p = 0.004). Moreover, a higher proportion of pediatric patients presented with intracranial hemorrhage (p < 0.001) and seizure (p = 0.002) compared to adult patients. Surgical resection was the most common brain VM treatment modality in both children and adults. We conclude that pediatric patients may be more likely to present with symptoms and complications from brain VMs, supporting the case for screening for brain VMs in children with HHT.

Published
2023

15. Surgical clipping and endovascular treatments for small or very small anterior communicating artery aneurysms: A comparative pooled analysis

Author

Batista, Sávio, Ferreira, Márcio Yuri, B. Oliveira, Leonardo, Semione, Gabriel, Bocanegra-Becerra, Jhon E., Bertani, Raphael, Palavani, Lucca B., de Macêdo Filho, Leonardo José Monteiro, Bertoli, Edmundo Damiani, Rabelo, Nicollas Nunes, Welling, Leonardo Christiaan, Figueiredo, Eberval G., and Lawton, Michael T.

Published
2024
Full Text
View/download PDF

17. History and Current State of Neurosurgery in the Gambia

Author

Bah, Momodou G., Elahi, Cyrus, Vaughan, Kerry A., Dampha, Lamin, Manneh, Ebrima K., Jabang, Isaac, Zainab, Jallow, Badiane, Seydou B., Thiam, Alioune B., Ndiaye, Papa I., Gaye-Sakho, Mayguette, Nyan, Ousman, Roberts, Charles A., Gail, Rosseau, Dilan, Ellegala, Lawton, Michael T., Youssoupha, Sakho, and Jabang, John N.

Published
2024
Full Text
View/download PDF

18. Most Promising Approaches to Improve Brain AVM Management: ARISE I Consensus Recommendations

Author

Samaniego, Edgar A., Dabus, Guilherme, Meyers, Philip M., Kan, Peter T., Frösen, Juhana, Lanzino, Giuseppe, Welch, Babu G., Volovici, Victor, Gonzalez, Fernando, Fifi, Johana, Charbel, Fady T., Hoh, Brian L., Khalessi, Alexander, Marks, Michael P., Berenstein, Alejandro, Pereira, Victor M., Bain, Mark, Colby, Geoffrey P., Narayanan, Sandra, Tateshima, Satoshi, Siddiqui, Adnan H., Wakhloo, Ajay K., Arthur, Adam S., and Lawton, Michael T.

Published
2024
Full Text
View/download PDF

19. Validation of the Ruptured Arteriovenous Malformation Grading Scale in a pediatric cohort.

Author

Garcia, Joseph H, Rutledge, Caleb, Winkler, Ethan A, Carrete, Luis, Morshed, Ramin A, Lu, Alex Y, Saggi, Satvir, Fox, Christine K, Fullerton, Heather J, Kim, Helen, Cooke, Daniel L, Hetts, Steven W, Lawton, Michael T, Gupta, Nalin, and Abla, Adib A

Subjects
Pediatric, Stroke, Clinical Research, Brain Disorders, Humans, Child, Retrospective Studies, Intracranial Arteriovenous Malformations, Intracranial Hemorrhages, ROC Curve, Aneurysm, Ruptured, Treatment Outcome, arteriovenous malformation, pediatric, disability, vascular disease, vascular disorders, Paediatrics and Reproductive Medicine, Neurology & Neurosurgery
Abstract

ObjectivePediatric brain arteriovenous malformations (AVMs) are the leading cause of spontaneous intracranial hemorrhage (SICH) in children. Although the incidence of SICH is low in pediatric populations, such events cause substantial morbidity. The recently created Ruptured Arteriovenous Malformation Grading Scale (RAGS) is proposed as a reliable and novel grading system to specifically serve as a predictor of clinical outcomes in patients following AVM rupture, similar to the Hunt and Hess (HH) grade for ruptured aneurysms. While these data are promising, pediatric patients were notably absent from the original study validating the RAGS. Therefore, correlation of the RAGS score with clinical outcomes following AVM rupture in individuals younger than 18 years of age using the RAGS score is needed. The objective of this study was to validate the RAGS in a cohort of pediatric patients with AVMs who presented with hemorrhage, thereby demonstrating the score's generalizability, and expanding its external validity.MethodsA cohort of children with ruptured AVMs were retrospectively reviewed. Using disability, measured by the modified Rankin Scale (mRS), as the response variable, the area under the receiver operating characteristic curve (AUROC) was calculated for patients based on their RAGS scores for three time periods. The AUROC values were then compared with those generated by two commonly used clinical grading systems, the HH classification and Glasgow Coma Scale.ResultsA total of 81 children who presented with ruptured AVMs were included in the study, with a mean follow-up duration of 4 years. The RAGS score outperformed other clinical grading scales in predicting mRS scores, with AUROC values of 0.81, 0.82, and 0.81 at three distinct follow-up periods.ConclusionsThe RAGS score correlated well with the clinical outcome after AVM rupture in pediatric patients. Additional validation studies across multiple treatment centers are needed to further demonstrate the generalizability of the scoring system.

Published
2022

20. De Novo Brain Vascular Malformations in Hereditary Hemorrhagic Telangiectasia

Author

Atherton, Mary E., Chakinala, Murali M., Clancy, Marianne S., Faughnan, Marie E., Gossage, James R., Hammill, Adrienne M., Henderson, Katharine, Hetts, Steven, Hountras, Peter, Iyer, Vivek, Kasthuri, Raj S., Kim, Helen, Krings, Timo, Lawton, Michael T., Lin, Doris, Mager, Johannes Jurgen, Marchuk, Douglas A., McWilliams, Justin P., McDonald, Jamie, Pawlikowska, Ludmila, Pollak, Jeffrey, Ratjen, Felix, Swanson, Karen, Vethanayagam, Dilini, Weinsheimer, Shantel, White, Andrew J., Whitehead, Kevin J., Wilcox, Pearce, Beslow, Lauren A., Hetts, Steven W., McCulloch, Charles E., Clancy, Marianne, and Bagheri, Negar

Published
2024
Full Text
View/download PDF

21. Posterior Inferior Cerebellar Artery-Posterior Inferior Cerebellar Artery Bypass versus Occipital Artery-Posterior Inferior Cerebellar Artery Bypass for Treating Posterior Circulation Aneurysms: A Systematic Review and Comparative Meta-Analysis

Author

Oliveira, Leonardo de Barros, Sousa, Marcelo Porto, Semione, Gabriel, Ferreira, Marcio Yuri, Batista, Sávio, Palavani, Lucca B., Andreão, Filipi F., Diniz, Jordana B.C., Rabelo, Nicollas Nunes, Bertani, Raphael, Welling, Leonardo C., Lawton, Michael T., and Figueiredo, Eberval Gadelha

Published
2024
Full Text
View/download PDF

23. Modafinil Therapy and Mental Status Following Aneurysmal Subarachnoid Hemorrhage: Comprehensive Stroke Center Analysis

Author

Koester, Stefan W., Rumalla, Kavelin, Catapano, Joshua S., Sorkhi, Samuel R., Mahadevan, Varun, Devine, Gregory P., Naik, Anant, Winkler, Ethan A., Rudy, Robert F., Baranoski, Jacob F., Cole, Tyler S., Graffeo, Christopher S., Srinivasan, Visish M., Jha, Ruchira M., Jadhav, Ashutosh P., Ducruet, Andrew F., Albuquerque, Felipe C., and Lawton, Michael T.

Published
2024
Full Text
View/download PDF

28. A single-cell atlas of the normal and malformed human brain vasculature

Author

Winkler, Ethan A, Kim, Chang N, Ross, Jayden M, Garcia, Joseph H, Gil, Eugene, Oh, Irene, Chen, Lindsay Q, Wu, David, Catapano, Joshua S, Raygor, Kunal, Narsinh, Kazim, Kim, Helen, Weinsheimer, Shantel, Cooke, Daniel L, Walcott, Brian P, Lawton, Michael T, Gupta, Nalin, Zlokovic, Berislav V, Chang, Edward F, Abla, Adib A, Lim, Daniel A, and Nowakowski, Tomasz J

Subjects
Biomedical and Clinical Sciences, Immunology, Stem Cell Research, Stem Cell Research - Nonembryonic - Human, Neurosciences, Brain Disorders, Stroke, 1.1 Normal biological development and functioning, Aetiology, 2.1 Biological and endogenous factors, Underpinning research, Adult, Blood Vessels, Brain, Cells, Cultured, Cerebral Cortex, Cerebral Hemorrhage, Cerebrovascular Circulation, Endothelial Cells, Fibroblasts, Humans, Inflammation, Intracranial Arteriovenous Malformations, Monocytes, Muscle, Smooth, Vascular, Pericytes, RNA-Seq, Single-Cell Analysis, Transcriptome, General Science & Technology
Abstract

Cerebrovascular diseases are a leading cause of death and neurologic disability. Further understanding of disease mechanisms and therapeutic strategies requires a deeper knowledge of cerebrovascular cells in humans. We profiled transcriptomes of 181,388 cells to define a cell atlas of the adult human cerebrovasculature, including endothelial cell molecular signatures with arteriovenous segmentation and expanded perivascular cell diversity. By leveraging this reference, we investigated cellular and molecular perturbations in brain arteriovenous malformations, which are a leading cause of stroke in young people, and identified pathologic endothelial transformations with abnormal vascular patterning and the ontology of vascularly derived inflammation. We illustrate the interplay between vascular and immune cells that contributes to brain hemorrhage and catalog opportunities for targeting angiogenic and inflammatory programs in vascular malformations.

Published
2022

29. Somatic mosaicism in the MAPK pathway in sporadic brain arteriovenous malformation and association with phenotype.

Author

Gao, Sen, Nelson, Jeffrey, Weinsheimer, Shantel, Winkler, Ethan A, Rutledge, Caleb, Abla, Adib A, Gupta, Nalin, Shieh, Joseph T, Cooke, Daniel L, Hetts, Steven W, Tihan, Tarik, Hess, Christopher P, Ko, Nerissa, Walcott, Brian P, McCulloch, Charles E, Lawton, Michael T, Su, Hua, Pawlikowska, Ludmila, and Kim, Helen

Subjects
Neurosciences, Genetics, 2.1 Biological and endogenous factors, Aetiology, Adolescent, Adult, Age of Onset, Aged, Child, Child, Preschool, Cohort Studies, DNA, Female, Genetic Variation, Humans, Intracranial Arteriovenous Malformations, Intracranial Hemorrhages, MAP Kinase Signaling System, Male, Middle Aged, Mosaicism, Mutation, Phenotype, Polymerase Chain Reaction, Prevalence, Proto-Oncogene Proteins p21(ras), Signal Transduction, Exome Sequencing, Young Adult, &nbsp, arteriovenous malformation, cerebrovascular malformation, somatic mutation, MAPK pathway, genotype-phenotype correlation, intracerebral hemorrhage, vascular disorders, Clinical Sciences, Neurology & Neurosurgery
Abstract

ObjectiveSporadic brain arteriovenous malformation (BAVM) is a tangled vascular lesion characterized by direct artery-to-vein connections that can cause life-threatening intracerebral hemorrhage (ICH). Recently, somatic mutations in KRAS have been reported in sporadic BAVM, and mutations in other mitogen-activated protein kinase (MAPK) signaling pathway genes have been identified in other vascular malformations. The objectives of this study were to systematically evaluate somatic mutations in MAPK pathway genes in patients with sporadic BAVM lesions and to evaluate the association of somatic mutations with phenotypes of sporadic BAVM severity.MethodsThe authors performed whole-exome sequencing on paired lesion and blood DNA samples from 14 patients with sporadic BAVM, and 295 genes in the MAPK signaling pathway were evaluated to identify genes with somatic mutations in multiple patients with BAVM. Digital droplet polymerase chain reaction was used to validate KRAS G12V and G12D mutations and to assay an additional 56 BAVM samples.ResultsThe authors identified a total of 24 candidate BAVM-associated somatic variants in 11 MAPK pathway genes. The previously identified KRAS G12V and G12D mutations were the only recurrent mutations. Overall, somatic KRAS G12V was present in 14.5% of BAVM lesions and G12D was present in 31.9%. The authors did not detect a significant association between the presence or allelic burden of KRAS mutation and three BAVM phenotypes: lesion size (maximum diameter), age at diagnosis, and age at ICH.ConclusionsThe authors confirmed the high prevalence of somatic KRAS mutations in sporadic BAVM lesions and identified several candidate somatic variants in other MAPK pathway genes. These somatic variants may contribute to understanding of the etiology of sporadic BAVM and the clinical characteristics of patients with this condition.

Published
2022

31. Association between external ventricular drain removal or replacement and prophylactic anticoagulation in patients with aneurysmal subarachnoid hemorrhage: a propensity-adjusted analysis

Author

Catapano, Joshua S., Koester, Stefan W., Parikh, Parth P., Rumalla, Kavelin, Stonnington, Henry O., Singh, Rohin, Winkler, Ethan A., Graffeo, Christopher S., Rudy, Robert F., Srinivasan, Visish M., Jha, Ruchira M., Jadhav, Ashutosh P., Albuquerque, Felipe C., Lawton, Michael T., and Ducruet, Andrew F.

Published
2023
Full Text
View/download PDF

41. Spetzler-Martin Grade III Arteriovenous Malformations: A Multicenter Propensity-Adjusted Analysis of the Effects of Preoperative Embolization

Author

Catapano, Joshua S, Frisoli, Fabio A, Nguyen, Candice L, Wilkinson, D Andrew, Majmundar, Neil, Cole, Tyler S, Baranoski, Jacob F, Whiting, Alexander C, Kim, Helen, Ducruet, Andrew F, Albuquerque, Felipe C, Cooke, Daniel L, Spetzler, Robert F, and Lawton, Michael T

Subjects
Biomedical and Clinical Sciences, Clinical Sciences, Pediatric, Congenital Structural Anomalies, Clinical Research, Patient Safety, Embolization, Therapeutic, Humans, Intracranial Arteriovenous Malformations, Microsurgery, Neurosurgical Procedures, Postoperative Complications, Preoperative Care, Propensity Score, Treatment Outcome, Arteriovenous malformation, Embolization, Spetzler-Martin grade, Neurosciences, Neurology & Neurosurgery, Clinical sciences, Biological psychology
Abstract

BackgroundSpetzler-Martin (SM) grade III arteriovenous malformations (AVMs) are at the boundary of safe operability, and preoperative embolization may reduce surgical risks.ObjectiveTo evaluate the benefits of preoperative AVM embolization by comparing neurological outcomes in patients with grade III AVMs treated with or without preoperative embolization.MethodsAll microsurgically treated grade III AVMs were identified from 2011 to 2018 at 2 medical centers. Neurological outcomes, measured as final modified Rankin Scale scores (mRS) and changes in mRS from preoperative baseline to last follow-up evaluation, were compared in patients with and without preoperative embolization.ResultsOf the 102 patients with grade III AVMs who were treated microsurgically, 57 (56%) underwent preoperative embolization. Significant differences were found between the patients with and without embolization in AVM eloquence (74% vs 93%, P = .02), size ≥ 3 cm (47% vs 73%, P = .01), diffuseness (7% vs 22%, P = .04), and mean final mRS (1.1 vs 2.0, P = .005). Poor outcomes were more frequent in patients without embolization (38%) than with embolization (7%) (final mRS > 2; P  2; odds ratio, 4.2; 95% CI, 1.1-16; P = .03).ConclusionNonembolization of SM grade III AVMs is associated with an increased risk of poor neurological outcomes after microsurgical resection. Preoperative embolization of intermediate-grade AVMs selected because of large AVM size, surgical inaccessibility of feeding arteries, and high flow should be employed more often than anticipated, even in the context of increasing microsurgical experience with AVMs.

Published
2021

45. Are preoperative chlorhexidine gluconate showers associated with a reduction in surgical site infection following craniotomy? A retrospective cohort analysis of 3126 surgical procedures.

Author

Ammanuel, Simon G, Edwards, Caleb S, Chan, Andrew K, Mummaneni, Praveen V, Kidane, Joseph, Vargas, Enrique, D'Souza, Sarah, Nichols, Amy D, Sankaran, Sujatha, Abla, Adib A, Aghi, Manish K, Chang, Edward F, Hervey-Jumper, Shawn L, Kunwar, Sandeep, Larson, Paul S, Lawton, Michael T, Starr, Philip A, Theodosopoulos, Philip V, Berger, Mitchel S, and McDermott, Michael W

Subjects
Patient Safety, surgical site infection, chlorhexidine, craniotomy, antisepsis, preoperative showers, Clinical Sciences, Neurosciences, Neurology & Neurosurgery
Abstract

ObjectiveSurgical site infection (SSI) is a complication linked to increased costs and length of hospital stay. Prevention of SSI is important to reduce its burden on individual patients and the healthcare system. The authors aimed to assess the efficacy of preoperative chlorhexidine gluconate (CHG) showers on SSI rates following cranial surgery.MethodsIn November 2013, a preoperative CHG shower protocol was implemented at the authors' institution. A total of 3126 surgical procedures were analyzed, encompassing a time frame from April 2012 to April 2016. Cohorts before and after implementation of the CHG shower protocol were evaluated for differences in SSI rates.ResultsThe overall SSI rate was 0.6%. No significant differences (p = 0.11) were observed between the rate of SSI of the 892 patients in the preimplementation cohort (0.2%) and that of the 2234 patients in the postimplementation cohort (0.8%). Following multivariable analysis, implementation of preoperative CHG showers was not associated with decreased SSI (adjusted OR 2.96, 95% CI 0.67-13.1; p = 0.15).ConclusionsThis is the largest study, according to sample size, to examine the association between CHG showers and SSI following craniotomy. CHG showers did not significantly alter the risk of SSI after a cranial procedure.

Published
2021

48. Outcomes in Patients with Aneurysmal Subarachnoid Hemorrhage Receiving Sulfonylureas: A Propensity-Adjusted Analysis

Author

Catapano, Joshua S., Koester, Stefan W., Bond, Kamila M., Srinivasan, Visish M., Farhadi, Dara S., Rumalla, Kavelin, Cole, Tyler S., Baranoski, Jacob F., Winkler, Ethan A., Graffeo, Christopher S., Muñoz-Casabella, Amanda, Jadhav, Ashutosh P., Ducruet, Andrew F., Albuquerque, Felipe C., Lawton, Michael T., and Jha, Ruchira M.

Published
2023
Full Text
View/download PDF

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

Author

Copelan, Alexander, Drocton, Gerald, Caton, M Travis, Smith, Eric R, Cooke, Daniel L, Nelson, Jeffrey, Abla, Adib A, Fox, Christine, Amans, Matthew R, Dowd, Christopher F, Halbach, Van V, Higashida, Randall T, Lawton, Michael T, Kim, Helen, Fullerton, Heather J, Gupta, Nalin, Hetts, Steven W, and UCSF Center For Cerebrovascular Research and UCSF Pediatric Brain Center

Subjects
UCSF Center For Cerebrovascular Research and UCSF Pediatric Brain Center, Brain, Humans, Intracranial Arteriovenous Malformations, Arteriovenous Fistula, Rupture, Recurrence, Angiography, Digital Subtraction, Treatment Outcome, Microsurgery, Neurosurgical Procedures, Retrospective Studies, Adolescent, Child, Child, Preschool, Female, Male, Young Adult, angiography, arteriovenous malformation, brain, intracranial hemorrhages, pediatrics, Stroke, Prevention, Congenital Structural Anomalies, Pediatric, Neurosciences, Clinical Research, Patient Safety, Cardiorespiratory Medicine and Haematology, Clinical Sciences, Neurology & Neurosurgery
Abstract

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.

Published
2020

Catalog

Books, media, physical & digital resources
See catalog results