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O'Neill B.E.,Methodist Hospital Research Institute | Vo H.Q.,Methodist Hospital Research Institute | Shao H.,Methodist Hospital Research Institute | Shao H.,Anhui University of Science and Technology | And 4 more authors.
Journal of Magnetic Resonance Imaging | Year: 2013

Purpose To design an algorithm for optimizing pulsed high intensity focused ultrasound (p-HIFU) treatment parameters to maximize tissue transport while minimizing thermal necrosis based on MR image guidance. Materials and Methods P-HIFU power, duty cycle, and treatment duration were varied to generate different levels of thermal and mechanical deposition in rabbit muscle. Changes in T2-weighted and T1 contrast-enhanced (CE) signal were assessed immediately following treatment and at 24 h. Transport parameters were extracted by means of T1-weighted dynamic contrast-enhanced MRI (DCE-MRI) technique at 0 and 24-h time points. Results Successful p-HIFU treatment was indicated by focal hyperintensity on the T2-weighted image immediately post-treatment, suggesting increased fluid (edema), with little intensity change in CE image. After 24 h, the affected region expanded along the muscle fiber accompanied by clear hyperintensity in CE image (contrast uptake). Quantitative DCE-MRI analysis revealed statistically significant increases in both leakage rate and extracellular space, accompanied by a decrease in clearance rate. Conclusion Successful p-HIFU treatment was mainly correlated to tissue heating. Tissue transport properties following treatment success would result in improved contact between drug and targets in both time and space. MRI is the key to controlling treatment by means of thermometry and also monitoring efficacy by means of T2-weighted imaging. J. Magn. Reson. Imaging 2013;38:1094-1102. © 2013 Wiley Periodicals, Inc. Copyright © 2013 Wiley Periodicals, Inc.

Barber C.R.,Baylor College of Medicine | Chang J.,Baylor College of Medicine | Tham Y.L.,Baylor College of Medicine | Kalidas M.,Austin Diagnostic Clinic | And 3 more authors.
Journal of Cancer Education | Year: 2010

Cognitive appraisal affects adjustment to breast cancer. A self-forgiving attitude and spirituality may benefit breast cancer survivors who blame themselves for their cancer. One hundred and eight women with early breast cancers completed questionnaires assessing self-blame, self-forgiveness, spirituality, mood and quality of life (QoL) in an outpatient breast clinic. Women who blamed themselves reported more mood disturbance (p<0.01) and poorer QoL (p<0.01). Women who were more self-forgiving and more spiritual reported less mood disturbance and better QoL (p's<0.01). Interventions that reduce self-blame and facilitate self-forgiveness and spirituality could promote better adjustment to breast cancer. © 2010 Springer.

Calleo J.,Michael bakey Veterans Affairs Medical Center | Calleo J.,Baylor College of Medicine | Burrows C.,Parkinsons Disease Research Education and Clinical Center | Levin H.,Michael bakey Veterans Affairs Medical Center | And 7 more authors.
Parkinson's Disease | Year: 2012

Cognitive dysfunction in Parkinson's disease contributes to disability, caregiver strain, and diminished quality of life. Cognitive rehabilitation, a behavioral approach to improve cognitive skills, has potential as a treatment option to improve and maintain cognitive skills and increase quality of life for those with Parkinson's disease-related cognitive dysfunction. Four cognitive rehabilitation programs in individuals with PD are identified from the literature. Characteristics of the programs and outcomes are reviewed and critiqued. Current studies on cognitive rehabilitation in PD demonstrate feasibility and acceptability of a cognitive rehabilitation program for patients with PD, but are limited by their small sample size and data regarding generalization of effects over the long term. Because PD involves progressive heterogeneous physical, neurological, and affective difficulties, future cognitive rehabilitation programs should aim for flexibility and individualization, according to each patient's strengths and deficits. Copyright © 2012 Jessica Calleo et al.

Marshall D.F.,Baylor College of Medicine | Strutt A.M.,Baylor College of Medicine | Williams A.E.,Baylor College of Medicine | Simpson R.K.,Methodist Hospital Neurological Institute | And 3 more authors.
European Journal of Neurology | Year: 2012

Background and purpose: Despite common occurrences of verbal fluency declines following bilateral subthalamic nucleus deep brain stimulation (STN-DBS) for the treatment of Parkinson's disease (PD), alternating fluency measures using cued and uncued paradigms have not been evaluated. Methods: Twenty-three STN-DBS patients were compared with 20 non-surgical PD patients on a comprehensive neuropsychological assessment, including cued and uncued intradimensional (phonemic/phonemic and semantic/semantic) and extradimensional (phonemic/semantic) alternating fluency measures at baseline and 6-month follow-up. Results: STN-DBS patients demonstrated a greater decline on the cued phonemic/phonemic fluency and the uncued phonemic/semantic fluency tasks compared to the PD patients. For STN-DBS patients, verbal learning and information processing speed accounted for a significant proportion of the variance in declines in alternating phonemic/phonemic and phonemic/semantic fluency scores, respectively, whilst only naming was related to uncued phonemic/semantic performance for the PD patients. Both groups were aided by cueing for the extradimensional task at baseline and follow-up, and the PD patients were also aided by cueing for the phonemic/phonemic task on follow-up. Conclusions: These findings suggest that changes in alternating fluency are not related to disease progression alone as STN-DBS patients demonstrated greater declines over time than the PD patients, and this change was related to declines in information processing speed. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.

Karmonik C.,Methodist key Heart and Vascular Center | Karmonik C.,Methodist Hospital Neurological Institute | Bismuth J.,Methodist key Heart and Vascular Center | Shah D.J.,Methodist key Heart and Vascular Center | And 3 more authors.
European Journal of Vascular and Endovascular Surgery | Year: 2011

Objectives: Outcome prediction in DeBakey Type III aortic dissections (ADs) remains challenging. Large variations in AD morphology, physiology and treatment exist. Here, we investigate if computational fluid dynamics (CFD) can provide an initial understanding of pressure changes in an AD computational model when covering entry and exit tears and removing the intra-arterial septum (IS). Design: A computational mesh was constructed from magnetic resonance images from one patient (one entrance and one exit tear) and CFD simulations performed (scenario #1). Additional meshes were derived by virtually (1) covering the exit tear (false lumen (FL) thrombus progression) (scenario #2), (2) covering the entrance tear (thoracic endovascular treatment, TEVAR) (scenario #3) and (3) completely removing the IS (fenestration) (scenario #4). Changes in flow patterns and pressures were quantified relative to the initial mesh. Results: Systolic pressures increased for #2 (300 Pa increase) with largest inter-luminal differences distally (2500 Pa). In #3, false lumen pressure decreased essentially to zero. In #4, systolic pressure in combined lumen reduced from 2400 to 800 Pa. Conclusions: CFD results from computational models of a DeBakey type III AD representing separate coverage of entrance and exit tears correlated with clinical experience. The reported results present a preliminary look at a complex clinical problem. © 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

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