A single case study examines the use of a curandera (Mexican folk healer) in helping a 22-year-ol... more A single case study examines the use of a curandera (Mexican folk healer) in helping a 22-year-old traditional first-generation raza (an in-group reference for identifying a Mexican individual of full or partial indigenous Mesoamerican heritage) male undergraduate student in a mid-sized city in the southwestern United States resolve grief issues. This article assesses the possible linkage between grief abreaction based on an atypical response to socio cultural gender expectancies relative to machismo (socially sanctioned Mexican male scripts for “gender-appropriate” behavior, identification, and role evaluations) and individually based universal grieving needs (Kubler-Ross, 1969; Parry, 1990, Salcido, 1990). It is posited that Mexican American mental health professionals may not always be viewed as sanctioned change agents by raza clients. Justifications and a need to examine and include traditional healers are briefly presented. A call for further exploration/ application of this practice is issued.
... Luis F. Gutiérrez, Guy Shechter, Robert J. Lederman, Elliot R. McVeigh, Cengizhan Ozturk ... ... more ... Luis F. Gutiérrez, Guy Shechter, Robert J. Lederman, Elliot R. McVeigh, Cengizhan Ozturk ... REFERENCES [1] R. Fahrig, K. Butts, J. Rowlands, R. Saunders, J. Stanton, G. Stevens, B. Daniel, Z. Wen, D. Ergun, and N. Pelc, A truly hybrid interventional MR/X-ray system: feasibility ...
To compare conventional magnetic resonance (MR) imaging, proton MR spectroscopic imaging, and dif... more To compare conventional magnetic resonance (MR) imaging, proton MR spectroscopic imaging, and diffusion tensor (DT) MR imaging findings in patients with X chromosome-linked adrenoleukodystrophy (X-ALD). Multisection proton MR spectroscopy and DT imaging were performed in 11 patients with X-ALD and in 11 healthy control subjects. Quantitative measures of N-acetylaspartate (NAA), choline, and creatine values and of isotropic apparent diffusion coefficient (IADC) and fractional anisotropy (FA) were obtained from coregistered regions of interest. DT imaging and metabolic parameters were compared by using regression analysis. In addition, differences in DT imaging and metabolite measurements between normal- and abnormal-appearing white matter on conventional MR images were evaluated by using a nonparametric (Mann-Whitney) test. A strong logarithmic relationship between NAA value and FA (r = 0.64, P <.001) and an inverse logarithmic relationship were found between NAA value and IADC (r = -0.69, P <.001). Creatine and choline values correlated poorly with IADC and FA. In the normal-appearing white matter of asymptomatic patients, the NAA value was 17% lower than that in the healthy control subjects (P =.016), whereas no significant difference in DT imaging measures was seen in these regions. In patients with X-ALD, MR spectroscopic imaging can depict abnormalities in white matter that have a normal appearance on both conventional MR and DT images; this finding suggests that it may be the most sensitive technique for detecting early abnormalities of demyelination or axonal loss in patients with X-ALD.
As we know during interventional studies X-ray angiography provides us a high resolution and refr... more As we know during interventional studies X-ray angiography provides us a high resolution and refresh rate, but as a trade off it doesn't have soft tissue contrast. MR imaging provides us 3-D anatomic imaging, and soft tissue contrast. Our aim is to fuse 2-D X-ray images with 3-D MR volume (XFM). We are using an intensity based algorithm to find mutual information between two modalities.
A system enabling both x-ray fluoroscopy and MRI in a single exam, without requiring patient repo... more A system enabling both x-ray fluoroscopy and MRI in a single exam, without requiring patient repositioning, would be a powerful tool for image-guided interventions. We studied the technical issues related to acquisition of x-ray images inside an open MRI system (GE Signa SP). The system includes a flat-panel x-ray detector (GE Medical Systems) placed under the patient bed, a fixed-anode x-ray tube overhead with the anode-cathode axis aligned with the main magnetic field and a high-frequency x-ray generator (Lunar Corp.). New challenges investigated related to: 1) deflection and defocusing of the electron beam of the x-ray tube; 2) proper functioning of the flat panel; 3) effects on B0 field homogeneity; and 4) additional RF noise in the MR images. We have acquired high-quality x-ray and MR images without repositioning the object using our hybrid system, which demonstrates the feasibility of this new configuration. Further work is required to ensure that the highest possible image quality is achieved with both MR and x-ray modalities.
Brain diffusion tensor MRI of 11 boys with X-linked adrenoleukodystrophy was performed. The autho... more Brain diffusion tensor MRI of 11 boys with X-linked adrenoleukodystrophy was performed. The authors determined quantitative isotropic apparent diffusion coefficient (ADC(i)) and fractional anisotropy (FA) values in the white matter. ADC(i) and FA values in the affected white matter were significantly different from those in normal-appearing white matter. Zonal ADC(i) and FA gradations, which might originate from well-established histopathologic zonal changes, existed within affected white matter.
... 5Correspondence Mr X - A Case of Amnesia YAIR DOMB and KATJA BEAMAN Squire & Slater, 1983... more ... 5Correspondence Mr X - A Case of Amnesia YAIR DOMB and KATJA BEAMAN Squire & Slater, 1983; Kopelman, 1985). ... He was co-operative in a rather passive way. His affect was flat. Only occasionally did he make eye contact. During ...
The present experiment investigated the effects of the decision freedom of a transgressor on attr... more The present experiment investigated the effects of the decision freedom of a transgressor on attributions of aggression and responsibility, and the assignment of punishment by naive observers. In a mass testing session Ss (N = 48 female college students) read one of four descriptions of Mr. X, a corporate vice president, who embezzled $50,000 under varying degrees of coercion. The degree of constraint operating on Mr. X prior to his decision to embezzle was manipulated by providing (or not providing) justifications for his behavior involving threats made upon the safety of Mr. X or his family. After reading a scenario Ss were asked to rate the aggressiveness of Mr. X on a semantic differential instrument and to indicate whether they perceived him as deserving of legal responsibility or punishment. Results revealed that constraints which reduced the transgressor's decision freedom also lessened the dispositional aggressiveness attributed, the blame assigned, and the retribution meted out to him. Additionally, it was found that observers considered the decision freedom of an actor even when the latter's action had been instigated by a coercive agent.
International Journal of Computer Assisted Radiology and Surgery, 2008
Objective A novel 3-D/2-D registration method based on matching 3-D pre-interventional image grad... more Objective A novel 3-D/2-D registration method based on matching 3-D pre-interventional image gradients and coarsely reconstructed 3-D gradients from intra-interventional 2-D images is presented. Material and methods The novel method establishes correspondences between two sets of gradients by searching for correspondences along normals to anatomical structures in 3-D images, while the final correspondences are established in an iterative process, combining the robust random sample consensus algorithm (RANSAC) and a special gradient matching criterion function. The proposed method was evaluated by the publicly available standardized evaluation methodology for 3-D/2-D registration, consisting of 3-D rotational X-ray, computed tomography (CT), magnetic resonance (MR), and 2-D X-ray images of two spine segments, and evaluation criteria. Results Preliminary results show significant improve- ment in robustness (capture range and success rate) over three well established intensity-based, gradient-based, and reconstruction-based methods. Conclusion The 3-D/2-D gradient reconstruction-based registration method efficiently combines the advantages of gradient and reconstruction-based methods, thereby enabling robust registration of CT and MR to only two X-ray images, while keeping the computational demands low.
Various multi-center trials have shown that cardiac resynchronization therapy (CRT) is an effecti... more Various multi-center trials have shown that cardiac resynchronization therapy (CRT) is an effective procedure for patients with end-stage drug invariable heart failure (HF). Despite the encouraging results of CRT, at least 30% of patients do not respond to the treatment. Detailed knowledge of the cardiac anatomy (coronary venous tree, left ventricle), functional parameters (i.e. ventricular synchronicity) is supposed to improve CRT patient selection and interventional lead placement for reduction of the number of non-responders. As a pre-interventional imaging modality, cardiac magnetic resonance (CMR) imaging has the potential to provide all relevant information. With functional information from CMR optimal implantation target sites may be better identified. Pre-operative CMR could also help to determine whether useful vein target segments are available for lead placement. Fused with X-ray, the mainstay interventional modality, improved interventional guidance for lead-placement could further help to increase procedure outcome. In this contribution, we present novel and practicable methods for a) pre-operative functional and anatomical imaging of relevant cardiac structures to CRT using CMR, b) 2D-3D registration of CMR anatomy and functional meshes with X-ray vein angiograms and c) real-time capable breathing motion compensation for improved fluoroscopy mesh overlay during the intervention based on right ventricular pacer lead tracking. With these methods, enhanced interventional guidance for left ventricular lead placement is provided.
Journal of Consulting and Clinical Psychology, 1999
Sixty therapists randomly assigned to 1 of 2 priming conditions were primed with African American... more Sixty therapists randomly assigned to 1 of 2 priming conditions were primed with African American stereotypes or neutral words using 80-ms flash words on a computer screen. This procedure may activate information processing outside of conscious awareness. After this task, participants were exposed to a brief vignette introducing Mr. X, a patient referred for treatment, and then were asked to rate Mr. X on various dimensions. Results indicate that participants primed with stereotype words rated Mr. X significantly less favorably on hostility-related attributes and significantly more favorably on hostility-unrelated attributes than did participants primed with neutral words. The findings suggest that therapists can be affected by African American stereotypes in ways that produce negative or positive first impressions depending on the nature of the attribute that is rated.
Most existing methods for registration of three-dimensional tomographic images to two-dimensional... more Most existing methods for registration of three-dimensional tomographic images to two-dimensional projection images use simulated projection images and either intensity-based or feature-based image similarity measures. This paper suggests a novel class of similarity measures based on probabilities. We compute intensity distributions along simulated rays through the 3-D image rather than ray sums. Using a finite state machine, we eliminate background voxels from the 3-D image while preserving voxels from air filled cavities and other low-intensity regions that are part of the imaged object (e.g., bone in MRI). The resulting tissue distributions along all rays are compared to the corresponding pixel intensities of the real projection image by means of a probabilistic extension of histogram-based similarity measures such as (normalized) mutual information. Because our method does not compute ray sums, its application, unlike DRR-based methods, is not limited to X-ray CT images. In the present paper, we show the ability of our similarity measure to successfully identify the correct position of an MR image with respect to a set of orthogonal DRRs computed from a co-registered CT image. In an initial evaluation, we demonstrate that the capture range of our similarity measure is approximately 40 mm with an accuracy of approximately 4 mm.
The purpose of this study was to provide in vivo demonstrations of the functionality of a truly h... more The purpose of this study was to provide in vivo demonstrations of the functionality of a truly hybrid interventional x-ray/magnetic resonance (MR) system.A digital flat-panel x-ray system (1,0242 array of 200 μm pixels, 30 frames per second) was integrated into an interventional 0.5-T magnet. The hybrid system is capable of MR and x-ray imaging of the same field of view without patient movement. Two intravascular procedures were performed in a 22-kg porcine model: placement of a transjugular intrahepatic portosystemic shunt (TIPS) (x-ray–guided catheterization of the hepatic vein, MR fluoroscopy–guided portal puncture, and x-ray–guided stent placement) and mock chemoembolization (x-ray–guided subselective catheterization of a renal artery branch and MR evaluation of perfused volume).The resolution and frame rate of the x-ray fluoroscopy images were sufficient to visualize and place devices, including nitinol guidewires (0.016–0.035-inch diameter) and stents and a 2.3-F catheter. Fifth-order branches of the renal artery could be seen. The quality of both real-time (3.5 frames per second) and standard MR images was not affected by the x-ray system. During MR-guided TIPS placement, the trocar and the portal vein could be easily visualized, allowing successful puncture from hepatic to portal vein.Switching back and forth between x-ray and MR imaging modalities without requiring movement of the patient was demonstrated. The integrated nature of the system could be especially beneficial when x-ray and MR image guidance are used iteratively.
A single case study examines the use of a curandera (Mexican folk healer) in helping a 22-year-ol... more A single case study examines the use of a curandera (Mexican folk healer) in helping a 22-year-old traditional first-generation raza (an in-group reference for identifying a Mexican individual of full or partial indigenous Mesoamerican heritage) male undergraduate student in a mid-sized city in the southwestern United States resolve grief issues. This article assesses the possible linkage between grief abreaction based on an atypical response to socio cultural gender expectancies relative to machismo (socially sanctioned Mexican male scripts for “gender-appropriate” behavior, identification, and role evaluations) and individually based universal grieving needs (Kubler-Ross, 1969; Parry, 1990, Salcido, 1990). It is posited that Mexican American mental health professionals may not always be viewed as sanctioned change agents by raza clients. Justifications and a need to examine and include traditional healers are briefly presented. A call for further exploration/ application of this practice is issued.
... Luis F. Gutiérrez, Guy Shechter, Robert J. Lederman, Elliot R. McVeigh, Cengizhan Ozturk ... ... more ... Luis F. Gutiérrez, Guy Shechter, Robert J. Lederman, Elliot R. McVeigh, Cengizhan Ozturk ... REFERENCES [1] R. Fahrig, K. Butts, J. Rowlands, R. Saunders, J. Stanton, G. Stevens, B. Daniel, Z. Wen, D. Ergun, and N. Pelc, A truly hybrid interventional MR/X-ray system: feasibility ...
To compare conventional magnetic resonance (MR) imaging, proton MR spectroscopic imaging, and dif... more To compare conventional magnetic resonance (MR) imaging, proton MR spectroscopic imaging, and diffusion tensor (DT) MR imaging findings in patients with X chromosome-linked adrenoleukodystrophy (X-ALD). Multisection proton MR spectroscopy and DT imaging were performed in 11 patients with X-ALD and in 11 healthy control subjects. Quantitative measures of N-acetylaspartate (NAA), choline, and creatine values and of isotropic apparent diffusion coefficient (IADC) and fractional anisotropy (FA) were obtained from coregistered regions of interest. DT imaging and metabolic parameters were compared by using regression analysis. In addition, differences in DT imaging and metabolite measurements between normal- and abnormal-appearing white matter on conventional MR images were evaluated by using a nonparametric (Mann-Whitney) test. A strong logarithmic relationship between NAA value and FA (r = 0.64, P <.001) and an inverse logarithmic relationship were found between NAA value and IADC (r = -0.69, P <.001). Creatine and choline values correlated poorly with IADC and FA. In the normal-appearing white matter of asymptomatic patients, the NAA value was 17% lower than that in the healthy control subjects (P =.016), whereas no significant difference in DT imaging measures was seen in these regions. In patients with X-ALD, MR spectroscopic imaging can depict abnormalities in white matter that have a normal appearance on both conventional MR and DT images; this finding suggests that it may be the most sensitive technique for detecting early abnormalities of demyelination or axonal loss in patients with X-ALD.
As we know during interventional studies X-ray angiography provides us a high resolution and refr... more As we know during interventional studies X-ray angiography provides us a high resolution and refresh rate, but as a trade off it doesn't have soft tissue contrast. MR imaging provides us 3-D anatomic imaging, and soft tissue contrast. Our aim is to fuse 2-D X-ray images with 3-D MR volume (XFM). We are using an intensity based algorithm to find mutual information between two modalities.
A system enabling both x-ray fluoroscopy and MRI in a single exam, without requiring patient repo... more A system enabling both x-ray fluoroscopy and MRI in a single exam, without requiring patient repositioning, would be a powerful tool for image-guided interventions. We studied the technical issues related to acquisition of x-ray images inside an open MRI system (GE Signa SP). The system includes a flat-panel x-ray detector (GE Medical Systems) placed under the patient bed, a fixed-anode x-ray tube overhead with the anode-cathode axis aligned with the main magnetic field and a high-frequency x-ray generator (Lunar Corp.). New challenges investigated related to: 1) deflection and defocusing of the electron beam of the x-ray tube; 2) proper functioning of the flat panel; 3) effects on B0 field homogeneity; and 4) additional RF noise in the MR images. We have acquired high-quality x-ray and MR images without repositioning the object using our hybrid system, which demonstrates the feasibility of this new configuration. Further work is required to ensure that the highest possible image quality is achieved with both MR and x-ray modalities.
Brain diffusion tensor MRI of 11 boys with X-linked adrenoleukodystrophy was performed. The autho... more Brain diffusion tensor MRI of 11 boys with X-linked adrenoleukodystrophy was performed. The authors determined quantitative isotropic apparent diffusion coefficient (ADC(i)) and fractional anisotropy (FA) values in the white matter. ADC(i) and FA values in the affected white matter were significantly different from those in normal-appearing white matter. Zonal ADC(i) and FA gradations, which might originate from well-established histopathologic zonal changes, existed within affected white matter.
... 5Correspondence Mr X - A Case of Amnesia YAIR DOMB and KATJA BEAMAN Squire & Slater, 1983... more ... 5Correspondence Mr X - A Case of Amnesia YAIR DOMB and KATJA BEAMAN Squire & Slater, 1983; Kopelman, 1985). ... He was co-operative in a rather passive way. His affect was flat. Only occasionally did he make eye contact. During ...
The present experiment investigated the effects of the decision freedom of a transgressor on attr... more The present experiment investigated the effects of the decision freedom of a transgressor on attributions of aggression and responsibility, and the assignment of punishment by naive observers. In a mass testing session Ss (N = 48 female college students) read one of four descriptions of Mr. X, a corporate vice president, who embezzled $50,000 under varying degrees of coercion. The degree of constraint operating on Mr. X prior to his decision to embezzle was manipulated by providing (or not providing) justifications for his behavior involving threats made upon the safety of Mr. X or his family. After reading a scenario Ss were asked to rate the aggressiveness of Mr. X on a semantic differential instrument and to indicate whether they perceived him as deserving of legal responsibility or punishment. Results revealed that constraints which reduced the transgressor's decision freedom also lessened the dispositional aggressiveness attributed, the blame assigned, and the retribution meted out to him. Additionally, it was found that observers considered the decision freedom of an actor even when the latter's action had been instigated by a coercive agent.
International Journal of Computer Assisted Radiology and Surgery, 2008
Objective A novel 3-D/2-D registration method based on matching 3-D pre-interventional image grad... more Objective A novel 3-D/2-D registration method based on matching 3-D pre-interventional image gradients and coarsely reconstructed 3-D gradients from intra-interventional 2-D images is presented. Material and methods The novel method establishes correspondences between two sets of gradients by searching for correspondences along normals to anatomical structures in 3-D images, while the final correspondences are established in an iterative process, combining the robust random sample consensus algorithm (RANSAC) and a special gradient matching criterion function. The proposed method was evaluated by the publicly available standardized evaluation methodology for 3-D/2-D registration, consisting of 3-D rotational X-ray, computed tomography (CT), magnetic resonance (MR), and 2-D X-ray images of two spine segments, and evaluation criteria. Results Preliminary results show significant improve- ment in robustness (capture range and success rate) over three well established intensity-based, gradient-based, and reconstruction-based methods. Conclusion The 3-D/2-D gradient reconstruction-based registration method efficiently combines the advantages of gradient and reconstruction-based methods, thereby enabling robust registration of CT and MR to only two X-ray images, while keeping the computational demands low.
Various multi-center trials have shown that cardiac resynchronization therapy (CRT) is an effecti... more Various multi-center trials have shown that cardiac resynchronization therapy (CRT) is an effective procedure for patients with end-stage drug invariable heart failure (HF). Despite the encouraging results of CRT, at least 30% of patients do not respond to the treatment. Detailed knowledge of the cardiac anatomy (coronary venous tree, left ventricle), functional parameters (i.e. ventricular synchronicity) is supposed to improve CRT patient selection and interventional lead placement for reduction of the number of non-responders. As a pre-interventional imaging modality, cardiac magnetic resonance (CMR) imaging has the potential to provide all relevant information. With functional information from CMR optimal implantation target sites may be better identified. Pre-operative CMR could also help to determine whether useful vein target segments are available for lead placement. Fused with X-ray, the mainstay interventional modality, improved interventional guidance for lead-placement could further help to increase procedure outcome. In this contribution, we present novel and practicable methods for a) pre-operative functional and anatomical imaging of relevant cardiac structures to CRT using CMR, b) 2D-3D registration of CMR anatomy and functional meshes with X-ray vein angiograms and c) real-time capable breathing motion compensation for improved fluoroscopy mesh overlay during the intervention based on right ventricular pacer lead tracking. With these methods, enhanced interventional guidance for left ventricular lead placement is provided.
Journal of Consulting and Clinical Psychology, 1999
Sixty therapists randomly assigned to 1 of 2 priming conditions were primed with African American... more Sixty therapists randomly assigned to 1 of 2 priming conditions were primed with African American stereotypes or neutral words using 80-ms flash words on a computer screen. This procedure may activate information processing outside of conscious awareness. After this task, participants were exposed to a brief vignette introducing Mr. X, a patient referred for treatment, and then were asked to rate Mr. X on various dimensions. Results indicate that participants primed with stereotype words rated Mr. X significantly less favorably on hostility-related attributes and significantly more favorably on hostility-unrelated attributes than did participants primed with neutral words. The findings suggest that therapists can be affected by African American stereotypes in ways that produce negative or positive first impressions depending on the nature of the attribute that is rated.
Most existing methods for registration of three-dimensional tomographic images to two-dimensional... more Most existing methods for registration of three-dimensional tomographic images to two-dimensional projection images use simulated projection images and either intensity-based or feature-based image similarity measures. This paper suggests a novel class of similarity measures based on probabilities. We compute intensity distributions along simulated rays through the 3-D image rather than ray sums. Using a finite state machine, we eliminate background voxels from the 3-D image while preserving voxels from air filled cavities and other low-intensity regions that are part of the imaged object (e.g., bone in MRI). The resulting tissue distributions along all rays are compared to the corresponding pixel intensities of the real projection image by means of a probabilistic extension of histogram-based similarity measures such as (normalized) mutual information. Because our method does not compute ray sums, its application, unlike DRR-based methods, is not limited to X-ray CT images. In the present paper, we show the ability of our similarity measure to successfully identify the correct position of an MR image with respect to a set of orthogonal DRRs computed from a co-registered CT image. In an initial evaluation, we demonstrate that the capture range of our similarity measure is approximately 40 mm with an accuracy of approximately 4 mm.
The purpose of this study was to provide in vivo demonstrations of the functionality of a truly h... more The purpose of this study was to provide in vivo demonstrations of the functionality of a truly hybrid interventional x-ray/magnetic resonance (MR) system.A digital flat-panel x-ray system (1,0242 array of 200 μm pixels, 30 frames per second) was integrated into an interventional 0.5-T magnet. The hybrid system is capable of MR and x-ray imaging of the same field of view without patient movement. Two intravascular procedures were performed in a 22-kg porcine model: placement of a transjugular intrahepatic portosystemic shunt (TIPS) (x-ray–guided catheterization of the hepatic vein, MR fluoroscopy–guided portal puncture, and x-ray–guided stent placement) and mock chemoembolization (x-ray–guided subselective catheterization of a renal artery branch and MR evaluation of perfused volume).The resolution and frame rate of the x-ray fluoroscopy images were sufficient to visualize and place devices, including nitinol guidewires (0.016–0.035-inch diameter) and stents and a 2.3-F catheter. Fifth-order branches of the renal artery could be seen. The quality of both real-time (3.5 frames per second) and standard MR images was not affected by the x-ray system. During MR-guided TIPS placement, the trocar and the portal vein could be easily visualized, allowing successful puncture from hepatic to portal vein.Switching back and forth between x-ray and MR imaging modalities without requiring movement of the patient was demonstrated. The integrated nature of the system could be especially beneficial when x-ray and MR image guidance are used iteratively.
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