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6413 citation(s) found for "Ma, Christopher".

Treatment of Axis Body Fractures
Kepler, Christopher K., Fleischman, Andrew N. , Traynelis, Vincent C. , Patel, Alpesh A. , Dekutoski, Mark B. , Wood, Kirkham B. , Schroeder, Gregory D. , Aarabi, Bizhan , Okonkwo, David O. , Fehlings, Michael G. , Shaffrey, Christopher I. , Kwon, Brian K. , Kepler, Christopher K. , Vaccaro, Alexander R. , Harrop, James Shields , Bransford, Richard Jackson , Arnold, Paul M. , Nassr, Ahmad , Fehlings, Michael G

Mayo Clinic

Clinical Spine Surgery: A Spine Publication | July 11, 2015 | Volume: 30 | Issue: 10 | Pages: 442-456

10.1097/bsd.0000000000000309 | PMID 29176489 Get It

Study Design: Evidence-based systematic review. Objectives: To define the optimal treatment of fractures involving the C2 body, including those with concomitant injuries, based upon a systematic review of the literature. Summary of Background Data: Axis body fractures have customarily been treated nonoperatively, but there are some injuries that may require operative intervention. High-quality literature is sparse and there are few class I or class II studies to guide treatment decisions. Materials and Methods: A literature search was conducted using PubMed (MEDLINE), Cochrane Central Register of Controlled Trials, and Scopus (EMBASE, MEDLINE, COMPENDEX). The quality of literature was rated according to a grading tool developed by the Center for Evidence-based Medicine. Operative and nonoperative treatment of axis body fractures were compared using fracture bony union as the primary outcome measure. As risk factors for nonunion were not consistently reported, cases were analyzed individually. Results: The literature search identified 62 studies, of which 10 were case reports which were excluded from the analysis. A total of 920 patients from 52 studies were included. The overall bony union rate for all axis body fractures was 91%. Although the majority of fractures were treated nonoperatively, there has been an increasing trend toward operative intervention for Benzel type III (transverse) axis body fractures. Nearly 76% of axis body fractures were classified as type III fractures, of which 88% united successfully. Nearly all Benzel type I and type II axis body fractures were successfully treated nonoperatively. The risk factors for nonunion included: a higher degree of subluxation, fracture displacement, comminution, concurrent injuries, delay in treatment, and older age. Conclusions: High rates for fracture union are reported in the literature for axis body fractures with nonoperative treatment. High-quality prospective studies are required to develop consensus as to which C2 body fractures require operative fixation.
Neuroophthalmological outcomes associated with use of the Pipeline Embolization Device: analysis of the PUFS trial results
Sahlein, Daniel H. , Fouladvand, Mohammad, Becske, Tibor , Saatçi, Işıl , McDougall, Cameron G. , Szikora, István , Moran, Christopher J. , Woo, Henry H. , Berez, Aaron L., Cher, Daniel , Siddiqui, Adnan H. , Albuquerque, Felipe C. , Berentei, Zsolt, Marosföi, Miklós , Cekirge, Saruhan H., Kallmes, David F. , Nelson, Peter K. , Lanzino, Giuseppe , Lopes, Demetrius K. , Levy, Elad I. , Fiorella, David , Siddiqui, Adnan H , Szikora, Istvan

Mayo Clinic

Journal of Neurosurgery | July 10, 2015 | Volume: 123 | Issue: 4 | Pages: 897-905

10.3171/2014.12.jns141777 | PMID 26162031 Get It

OBJECT Neuroophthalmological morbidity is commonly associated with large and giant cavernous and supraclinoid internal carotid artery (ICA) aneurysms. The authors sought to evaluate the neuroophthalmological outcomes after treatment of these aneurysms with the Pipeline Embolization Device (PED). METHODS The Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial was an international, multicenter prospective trial evaluating the safety and efficacy of the PED. All patients underwent complete neuroophthalmological examinations both before the PED procedure and at a 6-month follow-up. All examinations were performed for the purpose of this study and according to study criteria. RESULTS In total, 108 patients were treated in the PUFS trial, 98 of whom had complete neuroophthalmological follow-up. Of the patients with complete follow-up, 39 (40%) presented with a neuroophthalmological baseline deficit that was presumed to be attributable to the aneurysm, and patients with these baseline deficits had significantly larger aneurysms. In 25 of these patients (64%), the baseline deficit showed at least some improvement 6 months after PED treatment, whereas in 1 patient (2.6%), the deficits only worsened. In 5 patients (5%), new deficits had developed at the 6-month follow-up, while in another 6 patients (6%), deficits that were not originally assumed to be related to the aneurysm had improved by that time. A history of diabetes was associated with failure of the baseline deficits to improve after the treatment. The aneurysm maximum diameter was significantly larger in patients with a new deficit or a worse baseline deficit at 6 months postprocedure. CONCLUSIONS Patients treated with the PED for large and giant ICA aneurysms had excellent neuroophthalmological outcomes 6 months after the procedure, with deficits improving in most of the patients, very few deficits worsening, and few new deficits developing.
CSER and eMERGE: current and potential state of the display of genetic information in the electronic health record
Shirts, Brian H. , Salama, Joseph S , Aronson, Samuel , Gray, Stacy W. , Hindorff, Lucia A. , Jarvik, Gail P. , Tarczy‐Hornoch, Peter , Freimuth, Robert R. , Grundmeier, Robert W. , Hartzler, Andrea L. , Li, Rongling, Peissig, Peggy , Peterson, Josh F. , Rasmussen, Luke V. , Starren, Justin , Overby, Casey Lynnette, Taylor, Casey Overby , Chute, Christopher G. , Chung, Wendy K. , Plon, Sharon E. , Stoffel, Elena M. , Van Allen, Eliezer M , Weck, Karen E. , Williams, Marc S , Jarvik, Gail P , Rasmussen, Luke V , Freimuth, Robert R , Peterson, Josh F , Gray, Stacy W

Mayo Clinic

Journal of the American Medical Informatics Association | July 4, 2015 | Volume: 22 | Issue: 6 | Pages: 1231-1242

10.1093/jamia/ocv065 | PMID 26142422 Get It

Abstract Objective Clinicians’ ability to use and interpret genetic information depends upon how those data are displayed in electronic health records (EHRs). There is a critical need to develop systems to effectively display genetic information in EHRs and augment clinical decision support (CDS). Materials and Methods The National Institutes of Health (NIH)-sponsored Clinical Sequencing Exploratory Research and Electronic Medical Records & Genomics EHR Working Groups conducted a multiphase, iterative process involving working group discussions and 2 surveys in order to determine how genetic and genomic information are currently displayed in EHRs, envision optimal uses for different types of genetic or genomic information, and prioritize areas for EHR improvement. Results There is substantial heterogeneity in how genetic information enters and is documented in EHR systems. Most institutions indicated that genetic information was displayed in multiple locations in their EHRs. Among surveyed institutions, genetic information enters the EHR through multiple laboratory sources and through clinician notes. For laboratory-based data, the source laboratory was the main determinant of the location of genetic information in the EHR. The highest priority recommendation was to address the need to implement CDS mechanisms and content for decision support for medically actionable genetic information. Conclusion Heterogeneity of genetic information flow and importance of source laboratory, rather than clinical content, as a determinant of information representation are major barriers to using genetic information optimally in patient care. Greater effort to develop interoperable systems to receive and consistently display genetic and/or genomic information and alert clinicians to genomic-dependent improvements to clinical care is recommended.
Oncological control associated with surgical resection of isolated retroperitoneal lymph node recurrence of renal cell carcinoma
Russell, Christopher , Lue, Kathy, Fisher, John , Kassouf, Wassim , Schwaab, Thomas , Sexton, Wade J. , Psutka, Sarah P. , Thompson, R. Houston, Leibovich, Bradley C. , Hanzly, Michael, Boorjian, Stephen A. , Thompson, Robert Houston, Tanguay, Simon , Spiess, Philippe E. , Psutka, Sarah P

Mayo Clinic

BJU International | June 27, 2015 | Volume: 117 | Issue: 6B | Pages: No page available

10.1111/bju.13212 | PMID 26118331 Get It

Objective To evaluate the outcome of patients after surgical resection of isolated retroperitoneal lymph node ( RPLN ) recurrence of renal cell carcinoma ( RCC ) using a multicentre international cohort. Patients and Methods In all, 50 patients were identified who underwent resection of isolated RPLN recurrence of RCC at four institutions after nephrectomy for pT any N any M0 disease. Progression‐free ( PFS ) and cancer‐specific survival ( CSS ) were estimated using the Kaplan–Meier method. Cox proportional hazards regression models were used to assess the association of clinicopathological characteristics with disease progression. Results The median (interquartile range, IQR ) age at resection was 57.0 (50.0–62.5) years. The median ( IQR ) time to RPLN recurrence after nephrectomy was 12.6 (6.9–39.5) months, with no significant difference in median time to RPLN recurrence between patients with N+ disease at nephrectomy (10.7 [6.5–24.6] months) and those with Nx/pN0 disease at nephrectomy (13.7 [8.7–44.2] months) ( P = 0.66). The median ( IQR ) size of the RPLN recurrence before resection was 2.6 (1.9–5) cm. The most common site for RPLN recurrence was within the interaortocaval region (34%). The median ( IQR ) follow‐up after RPLN resection for patients alive at last follow‐up was 28.0 (13.7–51.2) months. During follow‐up, 26 patients developed RCC recurrence, at a median ( IQR ) of 9.9 (4.0–18.5) months after RPLN resection. Of those who developed a secondary recurrence, disease was again isolated to the retroperitoneum in seven patients. In all, 11 patients subsequently died, including 10 who died from disease. The median PFS after RPLN resection was 19.5 months, with a 3‐ and 5‐year PFS of 40.5% and 35.4%, respectively. We also found that RPLN recurrence at ≤12 months after nephrectomy was associated with a significantly inferior median PFS (12.3 months) compared with RPLN recurrence at >12 months after nephrectomy (47.6 months; P = 0.003). Moreover, on multivariate analysis, a shorter time to recurrence remained associated with a significantly increased risk for subsequent disease progression (hazard ratio 3.51; P = 0.005). Conclusion Surgical resection of isolated RPLN recurrence from RCC may result in durable cancer control in appropriately selected patients. Recurrence at ≤12 months after nephrectomy was associated with a significantly increased risk of progression after resection, underscoring the importance of this variable for risk stratification. Thus, we recommend that, in the setting of isolated RPLN recurrence of RCC (in patients without precluding comorbidities), careful consideration with the patients and medical oncology colleagues be undertaken about the relative and individualised benefits of surgical resection, systemic therapy, and surveillance.
Shared Decision-making in the Emergency Department: Respecting Patient Autonomy When Seconds Count
Grudzen, Corita R. , Thomson, Richard, Carpenter, Christopher R. , Hess, Erik P. , Raja, Ali S , Carpenter, Christopher R

Mayo Clinic

Academic Emergency Medicine | June 25, 2015 | Volume: 22 | Issue: 7 | Pages: 856-864

10.1111/acem.12703 | PMID 26112797 Get It

Apixaban in Comparison With Warfarin in Patients With Atrial Fibrillation and Valvular Heart Disease
Avezum, Álvaro , Schulte, Phillip J. , Laņas, Fernando , Hanna, Michael , Pais, Prem, Erol, Çetin , Díaz, Rafael , Bartunek, Jozef, Caterina, Raffaele De , Goto, Shinya , Rużyłło, Witold , Zhu, Jun , Granger, Christopher B., Alexander, John H. , Granger, Christopher B. , Hanna, Michael G. , Lópes, Renato D. , Bahit, M Cecilia, De Caterina, Raffaele, Ruzyllo, Witold, Gersh, Bernard J. , Bahit, Maria Cecilia , Granger, Christopher B , Lanas, Fernando

Mayo Clinic

Circulation | June 23, 2015 | Volume: 132 | Issue: 8 | Pages: 624-632

10.1161/circulationaha.114.014807 | PMID 26106009 Get It

Background— Apixaban is approved for the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. However, the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial included a substantial number of patients with valvular heart disease and only excluded patients with clinically significant mitral stenosis or mechanical prosthetic heart valves. Methods and Results— We compared the effect of apixaban and warfarin on rates of stroke or systemic embolism, major bleeding, and death in patients with and without moderate or severe valvular heart disease using Cox proportional hazards modeling. Of the 18 201 patients enrolled in ARISTOTLE, 4808 (26.4%) had a history of moderate or severe valvular heart disease or previous valve surgery. Patients with valvular heart disease had higher rates of stroke or systemic embolism and bleeding than patients without valvular heart disease. There was no evidence of a differential effect of apixaban over warfarin in patients with and without valvular heart disease in reducing stroke and systemic embolism (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.51–0.97 and HR, 0.84; 95%, CI 0.67–1.04; interaction P =0.38), causing less major bleeding (HR, 0.79; 95% CI, 0.61–1.04 and HR, 0.65; 95% CI, 0.55–0.77; interaction P =0.23), and reducing mortality (HR, 1.01; 95% CI, 0.84–1.22 and HR, 0.84; 95% CI, 0.73–0.96; interaction P =0.10). Conclusions— More than a quarter of the patients in ARISTOTLE with nonvalvular atrial fibrillation had moderate or severe valvular heart disease. There was no evidence of a differential effect of apixaban over warfarin in reducing stroke or systemic embolism, causing less bleeding, and reducing death in patients with and without valvular heart disease. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00412984.
Oral Contraceptive Use, Muscle Sympathetic Nerve Activity, and Systemic Hemodynamics in Young Women
Harvey, Ronée E. , Hart, Emma C. , Charkoudian, Nisha , Curry, Timothy B. , Carter, Jason R. , Fu, Qi , Minson, Christopher T. , Joyner, Michael J. , Barnes, Jill N. , Barnes, J N , Fu, Qi , Harvey, Ronée E , Joyner, Michael J , Carter, Jason R , Hart, Emma C

Mayo Clinic

Hypertension | June 23, 2015 | Volume: 66 | Issue: 3 | Pages: 590-597

10.1161/hypertensionaha.115.05179 | PMID 26101348 Get It

Endogenous female sex hormones influence muscle sympathetic nerve activity (MSNA), a regulator of arterial blood pressure and important factor in hypertension development. Although ≈80% of American women report using hormonal contraceptives sometime during their life, the influence of combined oral contraceptives (OCs) on MSNA and systemic hemodynamics remains equivocal. The goal of this study was to determine whether women taking OCs have altered MSNA and hemodynamics (cardiac output and total peripheral resistance) at rest during the placebo phase of OC use compared with women with natural menstrual cycles during the early follicular phase. We retrospectively analyzed data from studies in which healthy, premenopausal women (aged 18–35 years) participated. We collected MSNA values at rest and hemodynamic measurements in women taking OCs (n=53; 25±4 years) and women with natural menstrual cycles (n=74; 25±4 years). Blood pressure was higher in women taking OCs versus those with natural menstrual cycles (mean arterial pressure, 89±1 versus 85±1 mm Hg, respectively; P =0.01), although MSNA was similar in both groups (MSNA burst incidence, 16±1 versus 18±1 bursts/100 heartbeats, respectively; P =0.19). In a subset of women in which detailed hemodynamic data were available, those taking OCs (n=33) had similar cardiac output (4.9±0.2 versus 4.7±0.2 L/min, respectively; P =0.47) and total peripheral resistance (19.2±0.8 versus 20.0±0.9 U, respectively; P =0.51) as women with natural menstrual cycles (n=22). In conclusion, women taking OCs have higher resting blood pressure and similar MSNA and hemodynamics during the placebo phase of OC use when compared with naturally menstruating women in the early follicular phase.
The utility of cardiac biomarkers and echocardiography for the early detection of bevacizumab- and sunitinib-mediated cardiotoxicity
Bordun, Kimberly-Ann, Premecz, Sheena, daSilva, Megan, Mandal, Soma, Glavinovic, Tamara , Cheung, Matthew C. , Cheung, David, Chaudhary, Rakesh, Freed, Darren H. , Villarraga, Hector R. , Herrmann, Joerg , Ravandi, Amir , Thliveris, James A. , Pitz, Marshall , Singal, Pawan K. , Jassal, Davinder S. , Kohli, Manish , Mulvagh, Sharon, Mandal, Soma, Goyal, Vineet , White, Christopher W. , Chaudhary, Rakesh, Mulvagh, Sharon L.

Mayo Clinic

American Journal of Physiology-Heart and Circulatory Physiology | June 19, 2015 | Volume: 309 | Issue: 4 | Pages: H692-H701

10.1152/ajpheart.00172.2015 | PMID 26092985 Get It

The recent introduction of novel anticancer therapies, including bevacizumab (BVZ) and sunitinib (SNT), is associated with an increased risk of cardiotoxicity. However, early identification of left ventricular (LV) systolic dysfunction may facilitate dose modification and avoid the development of advanced heart failure. Using a murine model of BVZ- and SNT-mediated cardiotoxicity, we investigated whether cardiac biomarkers and/or tissue velocity imaging (TVI) using echocardiography can detect early changes in cardiac function, before a decrease in LV ejection fraction is identified. A total of 75 wild-type C57Bl/6 male mice were treated with either 0.9% saline, BVZ, or SNT. Serial monitoring of blood pressure, high-sensitivity troponin I, and echocardiographic indexes were performed over a 14-day study period, after which the mice were euthanized for histological and biochemical analyses. Mice treated with either BVZ or SNT developed systemic hypertension as early as day 7, which increased by day 14. Cardiac biomarkers, specifically high-sensitivity troponin I, were not predictive of early LV systolic dysfunction. Although conventional LV ejection fraction values decreased at day 13 in mice treated with either BVZ or SNT, TVI confirmed early LV systolic dysfunction at day 8. Histological and biochemical analysis demonstrated loss of cellular integrity, increased oxidative stress, and increased cardiac apoptosis in mice treated with BVZ or SNT therapy at day 14. In a murine model of BVZ- or SNT-mediated cardiomyopathy, noninvasive assessment by TVI detected early LV systolic dysfunction before alterations in conventional echocardiographic indexes.
Risk factors and analysis of long-term headache in sporadic vestibular schwannoma: a multicenter cross-sectional study
Carlson, Matthew L. , Tveiten, Øystein Vesterli , Driscoll, Colin L. W., Sullan, Molly J., Goplen, Frederik Kragerud , Lund‐Johansen, Morten , Link, Michael J. , Boes, Christopher J.

Mayo Clinic

Journal of Neurosurgery | June 19, 2015 | Volume: 123 | Issue: 5 | Pages: 1276-1286

10.3171/2014.12.jns142109 | PMID 26090830 Get It

OBJECT The primary goals of this study were: 1) to examine the influence of disease and treatment on headache in patients with sporadic vestibular schwannoma (VS); and 2) to identify clinical predictors of long-term headache disability. METHODS This was a cross-sectional observational study with international multicenter enrollment. Patients included those with primary sporadic < 3-cm VS and a separate group of general population control subjects without tumors. Interventions included a postal survey incorporating the Headache Disability Inventory (HDI), the Hospital Anxiety and Depression Scale, and a VS symptom questionnaire. The main outcome measures were univariate and multivariable associations with HDI total score. RESULTS The overall survey response rate was 79%. Data from 538 patients with VS were analyzed. The mean age at time of survey was 64 years, 56% of patients were female, and the average duration between treatment and survey was 7.7 years. Twenty-seven percent of patients received microsurgery, 46% stereotactic radiosurgery, and 28% observation. Patients with VS who were managed with observation were more than twice as likely to have severe headache disability compared with 103 control subjects without VS. When accounting for baseline differences, there was no statistically significant difference in HDI outcome between treatment modalities at time of survey. Similarly, among the microsurgery cohort, the long-term risk of severe headache disability was not different between surgical approaches. Multivariable regression demonstrated that younger age, greater anxiety and depression, and a preexisting diagnosis of headache were the primary predictors of severe long-term headache disability, while tumor size and treatment modality had little influence. CONCLUSIONS At a mean of almost 8 years following treatment, approximately half of patients with VS experience headaches of varying frequency and severity. Patient-driven factors including age, sex, mental health, and preexisting headache syndrome are the strongest predictors of long-term severe headache disability. Tumor size and treatment modality have less impact. These data may assist with patient counseling regarding long-term expectations following diagnosis and treatment.
Respiratory Infections in the U.S. Military: Recent Experience and Control
Sánchez, José L. , Cooper, Michael J. , Myers, Christopher A. , Cummings, James F. , Vest, Kelly G., Russell, Kevin L. , Sanchez, Joyce L. , Hiser, Michelle J., Gaydos, Charlotte A.

Mayo Clinic

Clinical Microbiology Reviews | June 18, 2015 | Volume: 28 | Issue: 3 | Pages: 743-800

10.1128/cmr.00039-14 | PMID 26085551 Get It

SUMMARYThis comprehensive review outlines the impact of military-relevant respiratory infections, with special attention to recruit training environments, influenza pandemics in 1918 to 1919 and 2009 to 2010, and peacetime operations and conflicts in the past 25 years. Outbreaks and epidemiologic investigations of viral and bacterial infections among high-risk groups are presented, including (i) experience by recruits at training centers, (ii) impact on advanced trainees in special settings, (iii) morbidity sustained by shipboard personnel at sea, and (iv) experience of deployed personnel. Utilizing a pathogen-by-pathogen approach, we examine (i) epidemiology, (ii) impact in terms of morbidity and operational readiness, (iii) clinical presentation and outbreak potential, (iv) diagnostic modalities, (v) treatment approaches, and (vi) vaccine and other control measures. We also outline military-specific initiatives in (i) surveillance, (ii) vaccine development and policy, (iii) novel influenza and coronavirus diagnostic test development and surveillance methods, (iv) influenza virus transmission and severity prediction modeling efforts, and (v) evaluation and implementation of nonvaccine, nonpharmacologic interventions.