Clinical Validation of Automatable Gaussian Normalized CBV in Brain Tumor Analysis: Superior Reproducibility and Slightly Better Association with Survival than Current Standard Manual Normal Appearing White Matter Normalization.

Purpose: To validate Gaussian normalized cerebral blood volume (GN-nCBV) by association with overall survival (OS) in newly diagnosed glioblastoma patients and compare this association with current standard white matter normalized cerebral blood volume (WN-nCBV).

Methods: We retrieved spin-echo echo-planar dynamic susceptibility contrast MRI acquired after maximal resection and prior to radiation therapy between 2006 and 2011 in 51 adult patients (28 male, 23 female; age 23-87 years) with newly diagnosed glioblastoma. Software code was developed in house to perform Gaussian normalization of CBV to the standard deviation of the whole brain CBV.

Quantification of radiation dose reduction by reducing z-axis coverage in 320-detector coronary CT angiography.

Objective: To quantify the radiation dose reduction achievable by minimizing z-axis coverage in 320-detector coronary CT angiography (CCTA).

Methods: We retrospectively reviewed 130 CCTAs performed on 320-detector CT that offers up to 16 cm z-axis coverage (adjustable in 2-cm increments), allowing complete coverage of the heart in a single gantry rotation. For each CT, we obtained the radiation dose [CT dose index and dose-length product (DLP)], measured the z-axis field of view and measured the craniocaudal cardiac size (distance from the left main coronary artery to the cardiac apex).

Percutaneous Image-Guided Cryoablation of Head and Neck Tumors for Local Control, Preservation of Functional Status, and Pain Relief.

Objective: We report nine consecutive percutaneous image-guided cryoablation procedures of head and neck tumors in seven patients (four men and three women; mean age, 68 years; age range, 50-78 years). Ablation of the entire tumor for local control or ablation of a region of tumor for pain relief or preservation of function was achieved in eight of nine procedures. One patient experienced intraprocedural bradycardia, and another developed a neopharyngeal abscess.

Computer-Based Vertebral Tumor Cryoablation Planning and Procedure Simulation Involving Two Cases Using MRI-Visible 3D Printing and Advanced Visualization.

Objective: We report the development and use of MRI-compatible and MRI-visible 3D printed models in conjunction with advanced visualization software models to plan and simulate safe access routes to achieve a theoretic zone of cryoablation for percutaneous image-guided treatment of a C7 pedicle osteoid osteoma and an L1 lamina osteoblastoma. Both models altered procedural planning and patient care.

Conclusion: Patient-specific MRI-visible models can be helpful in planning complex percutaneous image-guided cryoablation procedures.

Magnetic Resonance Imaging-Guided Spine Interventions.

MR imaging-guided interventions for treatment of low back pain and for diagnosis and treatment of soft tissue and bony spinal lesions have been shown to be feasible, effective, and safe. Advantages of this technique include the absence of ionizing radiation, the high tissue contrast, and multiplanar imaging options. Recent advancements in MR imaging systems allow improved image qualities and real-time guidance.

Myocyte injury along myofibers in left ventricular remodeling after myocardial infarction.

Left ventricular (LV) remodeling following myocardial infarction (MI) is considered to contribute to cardiac dysfunction. Though myofiber organization is a key component of cardiac structure, functional and anatomical features of injured myofiber during LV remodeling have not been fully defined. We investigated myocyte injury after acute MI in a mouse model.

VEGF and TGF-beta are required for the maintenance of the choroid plexus and ependyma.

Although the role of vascular endothelial growth factor (VEGF) in developmental and pathological angiogenesis is well established, its function in the adult is less clear. Similarly, although transforming growth factor (TGF) beta is involved in angiogenesis, presumably by mediating capillary (endothelial cell [EC]) stability, its involvement in quiescent vasculature is virtually uninvestigated. Given the neurological findings in patients treated with VEGF-neutralizing therapy (bevacizumab) and in patients with severe preeclampsia, which is mediated by soluble VEGF receptor 1/soluble Fms-like tyrosine kinase receptor 1 and soluble endoglin, a TGF-beta signaling inhibitor, we investigated the roles of VEGF and TGF-beta in choroid plexus (CP) integrity and function in adult mice.

In vivo MRI of embryonic stem cells in a mouse model of myocardial infarction.

The therapeutic potential of administering stem cells to promote angiogenesis and myocardial tissue regeneration after infarction has recently been demonstrated. Given the advantages of using embryonic stem cells and mouse models of myocardial infarction for furthering the development of this therapeutic approach, the purpose of this study was to determine if embryonic stem cells could be loaded with superparamagnetic iron oxide (SPIO) particles and imaged in a mouse model of myocardial infarction over time using MRI. Mouse embryonic stem cells were labeled with SPIO particles.

Magnetic resonance mapping of transplanted endothelial progenitor cells for therapeutic neovascularization in ischemic heart disease.

Objective: Intramyocardial transplantation of endothelial progenitor cells (EPCs) has been previously correlated with significant augmentation of vascularity and improvement of left ventricular function following myocardial ischemia. However, precise intramyocardial localization of the transplanted cells and the extent of in situ cell migration are unknown. We present a novel technique using magnetic resonance imaging (MRI) to localize transplanted EPCs in ischemic hearts.

Processing words with emotional connotation: an FMRI study of time course and laterality in rostral frontal and retrosplenial cortices.

Responses of rostral frontal and retrosplenial cortices to the emotional significance of words were measured using functional magnetic resonance imaging (fMRI). Twenty-six strongly right-handed participants engaged in a language task that alternated between silent word generation to categories with positive, negative, or neutral emotional connotation and a baseline task of silent repetition of emotionally neutral words. Activation uniquely associated with word generation to categories with positive or negative versus neutral emotional connotation occurred bilaterally in rostral frontal and retrosplenial cortices.

Src blockade stabilizes a Flk/cadherin complex, reducing edema and tissue injury following myocardial infarction.

Ischemia resulting from myocardial infarction (MI) promotes VEGF expression, leading to vascular permeability (VP) and edema, a process that we show here contributes to tissue injury throughout the ventricle. This permeability/edema can be assessed noninvasively by MRI and can be observed at the ultrastructural level as gaps between adjacent endothelial cells. Many of these gaps contain activated platelets adhering to exposed basement membrane, reducing vessel patency.

A pneumatic vibrotactile stimulation device for fMRI.

Mapping the functional response of the somatosensory cortex is useful both for characterizing normal brain activity and for determining the functional integrity of damaged cortex compromised by stroke or other neurological insults. A variety of stimulators have been used to produce somatosensory cortex activation in functional brain imaging, including brushes and swabs operated manually, pneumatically and mechanically powered mechanical vibrators, air puffs, and vibrating ceramic piezoelectric wafers and benders. A closed-system, pneumatically driven rubber diaphragm is reported that overcomes many of the limitations of existing vibrotactile devices and produces robust sensory cortex activation in an fMRI experiment.

Central representation of visceral and cutaneous hypersensitivity in the irritable bowel syndrome.

We have previously shown that irritable bowel syndrome (IBS) patients have both visceral and cutaneous hyperalgesia. The neural mechanisms of these forms of hyperalgesia were further characterized by comparing cortical processing of both rectal distension (35, 55mmHg) and cutaneous heat nociceptive stimuli (foot immersion in 45 and 47 degrees C water bath) in IBS patients and in a group of healthy age/sex-matched controls. Our approach relied on functional magnetic resonance imaging neuroimaging analyses in which brain activation in age/sex-matched control subjects was subtracted from that found in IBS patients.