Citations

Clear

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

Creating and Closing the T‐Capsulotomy for Improved Visualization During Arthroscopic Treatment of Femoroacetabular Impingement
Reardon, Patrick J., Levy, Bruce A. , Krych, Aaron J. , Camp, Christopher L. , Krych, Aaron J

Mayo Clinic

Arthroscopy Techniques | November 23, 2015 | Volume: 4 | Issue: 6 | Pages: No page available

10.1016/j.eats.2015.07.021 | PMID 26870654 Get It

Abstract Treatment of femoroacetabular impingement through an arthroscopic approach has gained widespread popularity in recent years. Although outcomes are generally favorable, one of the most common reasons for failure is incomplete resection of cam lesions of the femoral neck. As a result, the T‐capsulotomy has been introduced as a method for improving access to the femoral head‐neck junction, which is not always visible through a standard interportal capsulotomy. The T‐capsulotomy has the benefits of improving arthroscopic visualization of the femoral neck, reducing overall fluoroscopy exposure for the patient and surgeon, and facilitating capsular plication. We present a reliable and efficient method for creating and repairing the T‐capsulotomy. We routinely perform this technique in patients with cam lesions that are too large or too distal to safely visualize and decompress through an interportal capsulotomy. Technique Video video See video under supplementary data.
A Simple Technique for Capsular Repair After Hip Arthroscopy
Reardon, Patrick J., Levy, Bruce A. , Krych, Aaron J. , Camp, Christopher L. , Krych, Aaron J

Mayo Clinic

Arthroscopy Techniques | November 23, 2015 | Volume: 4 | Issue: 6 | Pages: No page available

10.1016/j.eats.2015.07.020 | PMID 26870655 Get It

Abstract Capsulotomy is typically performed during arthroscopic treatment for femoroacetabular impingement. As the frequency of hip arthroscopy continues to expand rapidly, increased attention is being paid to the implications of interportal capsulotomy and the need for repair. To minimize the risk of postoperative instability, capsular closure has been recommended to restore the anatomy and biomechanical function of the capsule. We present a reliable, efficient, and effective method for arthroscopic closure of the interportal capsulotomy after hip arthroscopy. Technique Video video See video under supplementary data.
Hemodynamic Characterization of Geometric Cerebral Aneurysm Templates Treated With Embolic Coils
Nair, Priya , Chong, Brian W. , Indahlastari, Aprinda , Workman, Christopher , Babiker, M. Haithem, Farsani, Hooman Yadollahi, Baccin, Carlos E. , Frakes, David , Ryan, Justin

Mayo Clinic

Journal of Biomechanical Engineering | November 23, 2015 | Volume: 138 | Issue: 2 | Pages: No page available

10.1115/1.4032046 | PMID 26593324 Get It

Embolic coiling is one of the most effective treatments for cerebral aneurysms (CAs), largely due to the hemodynamic modifications that the treatment effects in the aneurysmal environment. However, coiling can have very different hemodynamic outcomes in aneurysms with different geometries. Previous work in the field of biofluid mechanics has demonstrated on a general level that geometry is a driving factor behind aneurysmal hemodynamics. The goal of this study was to relate two specific geometric factors that describe CAs (i.e., dome size (DS) and parent-vessel contact-angle (PV-CA)) and one factor that describes treatment (i.e., coil packing density (PD)) to three clinically relevant hemodynamic responses (i.e., aneurysmal root-mean-square velocity (Vrms), aneurysmal wall shear stress (WSS), and cross-neck flow (CNF)). Idealized models of basilar tip aneurysms were created in both virtual and physical forms to satisfy two-level multifactorial experimental designs. Steady and pulsatile flow hemodynamics were then evaluated in the virtual models using computational fluid dynamics (CFD) (before and after virtual treatment with finite element (FE) embolic coil models), and hemodynamics were also evaluated in the physical models using particle image velocimetry (PIV) (before and after treatment with actual embolic coils). Results showed that among the factors considered, PD made the greatest contributions to effects on hemodynamic responses in and around the aneurysmal sac (i.e., Vrms and WSS), while DS made the greatest contributions to effects on hemodynamics at the neck (i.e., CNF). Results also showed that while a geometric factor (e.g., PV-CA) may play a relatively minor role in dictating hemodynamics in the untreated case, the same factor can play a much greater role after coiling. We consider the significance of these findings in the context of aneurysmal recurrence and rupture, and explore potential roles for the proposed methods in endovascular treatment planning.
Adverse Event Rates Associated with Transforaminal and Interlaminar Epidural Steroid Injections: A Multi-Institutional Study
El-Yahchouchi, Christine, Plastaras, Christopher T. , Maus, Timothy P. , McCormick, Zachary L. , Geske, Jennifer R. , Smuck, Matthew , Pingree, Matthew J. , Kennedy, David J. , Carr, Carrie M. , Geske, Jennifer

Mayo Clinic

Pain Medicine | November 23, 2015 | Volume: 17 | Issue: 2 | Pages: 239-247

10.1111/pme.12896 | PMID 26593277 Get It

Abstract Background. Transforaminal epidural steroid injections (TFESI) have demonstrated efficacy and effectiveness in treatment of radicular pain. Despite little evidence of efficacy/effectiveness, interlaminar epidural steroid injections (ILESI) are advocated by some as primary therapy for radicular pain due to purported greater safety. Objective. To assess immediate and delayed adverse event rates of TFESI and ILESI injections at three academic medical centers utilizing International Spine Intervention Society practice guidelines. Methods. Quality assurance databases from a Radiology and two physical medicine and rehabilitation (PM&R) practices were interrogated. Medical records were reviewed, verifying immediate and delayed adverse events. Results. There were no immediate major adverse events of neurologic injury or hemorrhage in 16,638 consecutive procedures in all spine segments (14,956 TFESI; 1,682 ILESI). Vasovagal reactions occurred in 1.2% of procedures, more frequently ( P = 0.004) in TFESI (1.3%) than ILESI (0.5%). Dural punctures occurred in 0.06% of procedures, more commonly after ILESI (0.2% vs 0.04%, P = 0.006). Delayed follow up on PM&R patients (92.5% and 78.5, next business day) and radiology patients (63.1%, 2 weeks) identified no major adverse events of neurologic injury, hemorrhage, or infection. There were no significant differences in delayed minor adverse event rates. Central steroid response (sleeplessness, flushing, nonpositional headache) was seen in 2.6% of both TFESI and ILESI patients. 2.1% of TFESI and 1.8% of ILESI patients reported increased pain. No long-term sequelae were seen from any immediate or delayed minor adverse event. Conclusions. Both transforaminal and ILESI are safely performed with low immediate and delayed adverse event rates when informed by evidence-based procedural guidelines. By demonstrating comparable safety, this study suggests that the choice between ILESI and TFESIs can be based on documented efficacy and effectiveness and not driven by safety concerns.
Minimally Invasive Prostate Convective Water Vapor Energy Ablation: A Multicenter, Randomized, Controlled Study for the Treatment of Lower Urinary Tract Symptoms Secondary to Benign Prostatic Hyperplasia
McVary, Kevin T. , Gange, Steven, Gittelman, Marc , Patel, Kalpesh, Levin, Richard, Rousseau, Michael, Beahrs, J. Randolf, Kaminetsky, Jed , Cowan, Barrett E., Cantrill, Christopher H., Mynderse, Lance A. , Ulchaker, James, Larson, Thayne R., Dixon, Christopher , Roehrborn, Claus G. , Goldberg, Kenneth A. , Shore, Neal D.

Mayo Clinic

Journal of Urology | November 22, 2015 | Volume: 195 | Issue: 5 | Pages: 1529-1538

10.1016/j.juro.2015.10.181 | PMID 26614889 Get It

Hindbrain regional growth in preterm newborns and its impairment in relation to brain injury
Kim, Hosung , Gano, Dawn , Ho, Mai‐Lan , Guo, Xiaoyue , Unzueta, Alisa, Xu, Duan , Barkovich, A. James , Hess, Christopher W. , Ferriero, Donna Marie , Ho, Mai-Lan

Mayo Clinic

Human Brain Mapping | November 21, 2015 | Volume: 37 | Issue: 2 | Pages: 678-688

10.1002/hbm.23058 | PMID 26589992 Get It

AbstractPremature birth globally affects about 11.1% of all newborns and is a risk factor for neurodevelopmental disability in surviving infants. Histology has suggested that hindbrain subdivisions grow differentially, especially in the third trimester. Prematurity‐related brain injuries occurring in this period may selectively affect more rapidly developing areas of hindbrain, thus accompanying region‐specific impairments in growth and ultimately neurodevelopmental deficits. The current study aimed to quantify regional growth of the cerebellum and the brainstem in preterm neonates (n =65 with individually multiple scans). We probed associations of the regional volumes with severity of brain injury. In neonates with no imaging evidence of injury, our analysis using a mixed‐effect linear model showed faster growth in the pons and the lateral convexity of anterior/posterior cerebellar lobes. Different patterns of growth impairment were found in relation to early cerebral intraventricular hemorrhage and cerebellar hemorrhage (P <0.05), likely explaining different mechanisms through which neurogenesis is disrupted. The pattern of cerebellar growth identified in our study agreed excellently with details of cerebellar morphogenesis in perinatal development, which has only been observed in histological data. Our proposed analytic framework may provide predictive imaging biomarkers for neurodevelopmental outcome, enabling early identification and treatment of high‐risk patients.Hum Brain Mapp 37:678–688, 2016. ©2015 Wiley Periodicals, Inc.
Dural arteriovenous fistula-induced thalamic dementia: report of 4 cases
Holekamp, Terrence F., Mollman, Matthew E., Murphy, Rory K. J. , Kolar, Grant R. , Kramer, Neha M. , Derdeyn, Colin P. , Moran, Christopher J. , Perrin, Richard J. , Rich, Keith M. , Zipfel, Gregory J. , Lanzino, Giuseppe , Derdeyn, Colin P

Mayo Clinic

Journal of Neurosurgery | November 20, 2015 | Volume: 124 | Issue: 6 | Pages: 1752-1765

10.3171/2015.5.jns15473 | PMID 26587655 Get It

Nonhemorrhagic neurological deficits are underrecognized symptoms of intracranial dural arteriovenous fistulas (dAVFs) having cortical venous drainage. These symptoms are the consequence of cortical venous hypertension and portend a clinical course with increased risk of neurological morbidity and mortality. One rarely documented and easily misinterpreted type of nonhemorrhagic neurological deficit is progressive dementia, which can result from venous hypertension in the cortex or in bilateral thalami. The latter, which is due to dAVF drainage into the deep venous system, is the less common of these 2 dementia syndromes. Herein, the authors report 4 cases of dAVF with venous drainage into the vein of Galen causing bithalamic edema and rapidly progressive dementia. Two patients were treated successfully with endovascular embolization, and the other 2 patients were treated successfully with endovascular embolization followed by surgery. The radiographic abnormalities and presenting symptoms rapidly resolved after dAVF obliteration in all 4 cases. Detailed descriptions of these 4 cases are presented along with a critical review of 15 previously reported cases. In our analysis of these 19 published cases, the following were emphasized: 1) the clinical and radiographic differences between dAVF-induced thalamic versus cortical dementia syndromes; 2) the differential diagnosis and necessary radiographic workup for patients presenting with a rapidly progressive thalamic dementia syndrome; 3) the frequency at which delays in diagnosis occurred and potentially dangerous and avoidable diagnostic procedures were used; and 4) the rapidity and completeness of symptom resolution following dAVF treatment.
S0502: A SWOG Phase III Randomized Study of Imatinib, With or Without Bevacizumab, in Patients With Untreated Metastatic or Unresectable Gastrointestinal Stromal Tumors
Blanke, Charles D. , Rankin, Cathy, Corless, Christopher L. , Eary, Janet F. , Mulder, Karen , Okuno, Scott H. , Heinrich, Michael C. , George, Suzanne , Heinrich, Michael C

Mayo Clinic

The Oncologist | November 18, 2015 | Volume: 20 | Issue: 12 | Pages: 1353-1354

10.1634/theoncologist.2015-0295 | PMID 26576593 Get It

Abstract Lessons Learned Despite having significant rationale, S0502 failed to accrue for a number of reasons. Vetting a trial first, with scientific experts and funding agencies, does not guarantee success, especially when dealing with a rare tumor and/or one with an existing highly effective therapy. In the present case, adding an intravenous drug to an oral medication as part of a regimen expected to be continued for many years likely decreased patient (and physician) convenience and, thus, interest in the study. Background. Imatinib mesylate, a potent inhibitor of the KIT and PDGFR tyrosine kinases, is highly effective in the treatment of advanced gastrointestinal stromal tumors (GISTs). However, most imatinib-treated tumors eventually become resistant, accounting for a median progression-free survival of 19–23 months. Expression of vascular endothelial growth factor (VEGF) correlates with poor prognosis in GIST; bevacizumab, a monoclonal antibody against VEGF, is effective in a variety of solid tumors. We postulated combination therapy with imatinib plus bevacizumab would benefit patients with advanced GIST, particularly those reliant on VEGFA-dependent angiogenesis. Methods. Patients with metastatic or surgically unresectable GIST were eligible for this phase III open-label clinical trial, S0502. At registration, patients were randomly assigned to either imatinib 400 mg (standard) or 800 mg (patients with exon 9 KIT mutations), or imatinib plus bevacizumab, 7.5 mg/kg i.v. every 3 weeks. Patients were treated to progression, symptomatic deterioration, unacceptable toxicity, treatment delay greater than 4 weeks, or patient choice to withdraw from the study. The primary objective was to determine whether the addition of bevacizumab to imatinib would improve progression-free survival (PFS) in first-line treatment of incurable GIST. Results. S0502 opened on April 15, 2008. As of fall 2009, only 12 patients from at least 178 eligible SWOG centers plus those participating through Cancer Trials Support Unit had been entered in the study. Despite an aggressive promotion scheme involving the other cooperative groups and a major GIST patient advocacy group, accrual remained slow. The trial was closed on October 1, 2009, having accrued only 2% of the 572 patients planned. No scientific conclusions were forthcoming because of the small number of patients entered in the study. Two patients of the 6 in the combination arm reported grade 3 toxicities, 1 with proteinuria and 1 with fatigue, upper gastrointestinal hemorrhage, and anemia. Conclusion. No conclusions may be drawn from this trial and, thus, the combination of imatinib plus bevacizumab cannot be recommended for use.
Advancing Patient‐centered Outcomes in Emergency Diagnostic Imaging: A Research Agenda
Kanzaria, Hemal K., McCabe, Aileen , Meisel, Zachary, Schaffer, Jason T. , Bellolio, Fernanda , Vaughan, William P., Merck, Lisa H. , Applegate, Kimberly E. , Grudzen, Corita R. , Mills, Angela M. , Carpenter, Christopher R. , LeBlanc, Annie , Bellolio, M Fernanda, Hollander, Judd E. , Hess, Erik P. , Bellolio, M Fernanda , Carpenter, Christopher R , Mills, Angela M

Mayo Clinic

Academic Emergency Medicine | November 17, 2015 | Volume: 22 | Issue: 12 | Pages: 1435-1446

10.1111/acem.12832 | PMID 26574729 Get It

AbstractDiagnostic imaging is integral to the evaluation of many emergency department (ED) patients. However, relatively little effort has been devoted to patient‐centered outcomes research (PCOR) in emergency diagnostic imaging. This article provides background on this topic and the conclusions of the 2015 Academic Emergency Medicine consensus conference PCOR work group regarding “Diagnostic Imaging in the Emergency Department: A Research Agenda to Optimize Utilization.” The goal was to determine a prioritized research agenda to establish which outcomes related to emergency diagnostic imaging are most important to patients, caregivers, and other key stakeholders and which methods will most optimally engage patients in the decision to undergo imaging. Case vignettes are used to emphasize these concepts as they relate to a patient's decision to seek care at an ED and the care received there. The authors discuss applicable research methods and approaches such as shared decision‐making that could facilitate better integration of patient‐centered outcomes and patient‐reported outcomes into decisions regarding emergency diagnostic imaging. Finally, based on a modified Delphi process involving members of the PCOR work group, prioritized research questions are proposed to advance the science of patient‐centered outcomes in ED diagnostic imaging.
Clinical-Genetic Associations in the Prospective Huntington at Risk Observational Study (PHAROS)
Investigators, The Huntington Study Group PHAROS, Biglan, Kevin , Shoulson, Ira , Kieburtz, Karl , Oakes, David , Kayson, Elise, Shinaman, M. Aileen, Zhao, Hongwei , Romer, Megan, Young, Anne B., Hersch, Steven M. , Penney, Jack, Marder, Karen, Paulsen, Jane S. , Quaid, Kimberly A., Siemers, Eric , Mallonee, William, Suter, Greg, Dubinsky, Richard , Nance, Martha , Bundlie, Scott R., Radtke, Dawn, Kostyk, Sandra K. , Baic, Corrine, Walker, Francis O. , Hunt, Victoria, Chouinard, Sylvain, Wood‐Siverio, Cathy, Corey‐Bloom, Jody , Peavy, Guerry M. , Moskowitz, Carol, Wesson, Melissa, Samii, Ali, Bird, Thomas D. , Lipe, Hillary, Blindauer, Karen, Marshall, Frederick J., Zimmerman, Carol, Goldstein, Jody, Rosas, Diana, Novák, Péter , Caviness, John N., Duffy, Amy, Wheelock, Vicki, Tempkin, Teresa, Seeberger, Lauren , Albin, Roger L. , Racette, Brad A. , Perlman, Susan , Bordelon, Yvette , Martin, W. R. Wayne , Wieler, Marguerite , Raymond, Lynn A. , Decolongon, Joji, Hunter, Christine , Hauser, Robert A. , Furtado, Sarah , Suchowersky, Oksana , Klimek, Mary Lou, Guttman, Mark, Sethna, Rustom, Feigin, Andrew, Cox, Marie, Shannon, Barbara , Percy, Alan K. , Dure, Leon , Harrison, Madaline B. , Higgins, Donald S. , Molho, Eric , Nickerson, Constance, Evans, Sharon, Hobson, Douglas, Singer, Carlos , Gálvez-Jiménez, Néstor, Shannon, Kathleen M. , Comella, Cynthia , Ross, Christopher A. , Hogarth, Penelope , Weiner, William J., Como, Peter G., Kumar, Rajeev , Cotto, Candace, Stout, Julie C. , Brocht, Alicia, Watts, Arthur, Eberly, Shirley , Weaver, Christine , Gusella, James F. , MacDonald, Marcy E., Fahn, Stanley, Shults, Clifford W., Caviness, John, Investigators, The Huntington Study Group PHAROS, Tanner, Caroline M. , Gray, Carolyn Steele , Baic, Corrine L., Caress, James B. , O’Neill, Christine J. , Factor, Stewart Alan , Greenamyre, J. Timothy , Song, David , Adler, Charles H. , Richman, David P. , Chou, Kelvin L. , Perlmutter, Joel S. , Leavitt, Blair R. , Clarke, Lorne A. , Jankovic, Joseph J. , Sanchez‐Ramos, Juan , Johnson, William , Saint‐Hilaire, Marie , Testa, Claudia M. , Rosenblatt, Adam E , Foroud, Tatiana , Myers, Richard H. , Ross, Christopher A , Hauser, Robert A

Mayo Clinic

JAMA Neurology | November 16, 2015 | Volume: 73 | Issue: 1 | Pages: 102

10.1001/jamaneurol.2015.2736 | PMID 26569098 Get It