Brain Imaging Patterns Moving Closer To Identifying Schizophrenia on Functional MRI

MedicalResearch.com Interview with:

Irina Rish PhD IBM T.J. Watson Research Center Yorktown Heights, NY 10598

Dr. Rish

Irina Rish PhD
IBM T.J. Watson Research Center
Yorktown Heights, NY 10598 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Schizophrenia is a chronic and severe psychiatric disorder that affects roughly about 1% of population. Although it is not as common as other mental disorders, such as depression, anxiety, and attention deficit disorder (ADD), and so on, schizophrenia  is perhaps one of  the most debilitating psychiatric disorders,  preventing people from normal  functioning in daily life. It is characterized primarily by a range of psychotic symptoms, including hallucinations (false auditory, visual or tactile perceptions detached from reality), as well as delusions, disorganized thoughts, speech and behavior, and multiple other symptoms including difficulty showing (and recognizing) emotions, poor executive functioning, inattentiveness, problems with working memory,  and so one. Overall, schizophrenia has a devastating impact not only on patients and their families, but on the economy, as it was estimated to cost the US about 2% off  gross national product in treatment costs, missed work, etc.
Thus, taking steps towards better understanding of the disease can potentially lead to more accurate early diagnosis and better treatments.

In this work, the objective was to identify “statistical biomarkers’ of schizophrenia from brain imaging data (specifically, functional MRI), i.e. brain activity patterns that would be capable of accurately discriminating between schizophrenic patients and controls, and reproducible (stable) across multiple datasets. The focus on both predictive accuracy (generalization to previously unseen subjects) as well as on stability (reproducibility) across multiple datsets differentiates our work from majority of similar studies in neuroimaging field that tend to focus only on statistically significant differences between such patterns on a fixed dataset, and may not reliably generalize to new data.

Our prior work on neuroimaging-based analysis of schizoprenia http://journals.plos.org/plosone/article/related?id=10.1371/journal.pone.0050625, as well as other research in the field, suggest that disrupted functional connectivity can be a much more informative source of discriminative patterns than local changes in brain activations, since schizophrenia is well known to be a “network disease”, rather than a localized one.

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MRI Biomarkers Track Cognitive Impairment Due to Head Trauma

MedicalResearch.com Interview with:

Virendra Mishra, Ph.D. Department of Imaging Research Cleveland Clinic Lou Ruvo Center for Brain Health in Las Vegas

Dr. Virendra Mishra

Virendra Mishra, Ph.D.
Department of Imaging Research
Cleveland Clinic Lou Ruvo Center for Brain Health in Las Vegas

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Repetitive head trauma has been shown to be a risk factor for various neurodegenerative disorders, mood swings, depression and chronic traumatic encephalopathy. There has been a significant amount of research into identifying an imaging biomarker of mild traumatic brain injury (mTBI) due to repetitive head trauma. Unfortunately, most of the biomarkers have not been able to find a successful translation to clinics. Additionally, the quest for the mTBI imaging biomarker especially using Magnetic Resonance Imaging (MRI) techniques has been done by looking at either the gray matter (T1-weighted) or the white matter (Diffusion Tensor Imaging) independently; and both have shown changes that are associated with repetitive head trauma.

Hence in this study, we wanted to investigate if combining gray matter and white matter information enables us to better predict the fighters who are more vulnerable to cognitive decline due to repetitive head trauma. Our method found seven imaging biomarkers that when combined together in a multivariate sense were able to predict with greater than 73% accuracy those fighters who are vulnerable to cognitive decline both at baseline and follow-up. The imaging biomarkers were indeed a combination of gray and white matter measures of regions reported previously in the literature. A key point in our study was we found the regions predicting cognitive decline without enforcing any assumptions on the regions previously reported.

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Photodynamic Therapy Being Developed To Target Prostate Cancer

MedicalResearch.com Interview with:
Dr. Susanne Lütje
Ärztlicher Dienst
Universitätsklinikum Essen (AöR)
Klinik für Nuklearmedizin
Essen Germany

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Prostate cancer (PCa) is the most common cancer in men and accounts for a significant amount of morbidity and mortality. At present, the curative treatment option of choice for localized stages of PCa is radical prostatectomy, which may include extended lymph node dissection. Unfortunately, surgical procedures can be accompanied by complications such as urinary incontinence. Most importantly, small tumor deposits may not be seen by the surgeon during surgery and could ultimately lead to disease recurrence. To overcome these issues, new and innovative treatments are needed. The prostate-specific membrane antigen (PSMA) is a surface protein that is overexpressed in prostate cancer and can be used as a target to guide new therapies.

Photodynamic therapy (PDT) is an ablative procedure in which tumor cells can be destroyed effectively by irradiation of light of a specific wavelength, which activates previously administered photosensitizers. The photosensitizers can respond by emitting fluorescence or emitting oxygen radicals which can cause cellular damage. Coupling the photosensitizer to an agent that targets PSMA on the tumor surface offers the possibility to selectively and effectively destroy prostate tumor remnants and micrometastases, while surrounding healthy tissues remain unaffected.

In our study, the PSMA targeting antibody D2B was coupled to the photosensitizer IRDye700DX and radiolabeled with 111In. In a mouse model, this multi-modality agent was used to preoperatively visualize tumor lesions with SPECT/CT to allow rough localization of the tumors. During surgery, the fluorescent signal originating from the photosensitizer facilitates visualization of tumors and residual tumor tissue, so the surgeon can be guided towards accurate resection of the entire tumors and metastases. In addition, the PSMA-targeted PDT can be applied to destroy small tumor deposits in cases where close proximity of the tumors.

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MRI At Six Months Can Predict Which High Risk Babies Will Develop Autism

MedicalResearch.com Interview with:

Joseph Piven, MD The Thomas E. Castelloe Distinguished Professor of Psychiatry UNC School of Medicine Director of the Carolina Institute for Developmental Disabilities Co-senior author of the study

Dr. Piven

Joseph Piven, MD
The Thomas E. Castelloe Distinguished Professor of Psychiatry
UNC School of Medicine
Director of the Carolina Institute for Developmental Disabilities
Co-senior author of the study

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Babies with older siblings with autism are at an increased risk (20%) of getting autism over the general population (1%).  Infants who later are diagnosed with autism don’t have any of the stigmata of autism in the first year of life. The symptoms of autism unfold in the first and particularly in the second year of life and beyond.

We have evidence to support the idea that behavioral symptoms of autism arise from changes in the brain that occur very early in life. So we have employed MRI and computer analyses to study those early brain changes and abnormalities in infancy to see if early brain changes at 6 months of age can predict whether babies at high-risk of developing autism will indeed develop the condition at age two.

For this particular study, we used data from MRIs of six-month olds to show the pattern of synchronization or connection across brain regions throughout the brain and then predict which babies at high familial risk of developing autism would be most likely to be diagnosed with the condition at age two.

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Diagnostic Accuracy of FFR-CT Varies Across Spectrum of Coronary Artery Disease

MedicalResearch.com Interview with:
Dr Christopher Michael Cook MBBS Bsc(Hons) MRCP

MRC Clinical Research Fellow
NHLI, Cardiovascular Medicine, Imperial College London 

MedicalResearch.com: What is the background for this study?

Response: FFR-CT is a novel non-invasive technique for estimating the functional significance of a coronary stenosis from CT coronary angiography images. A number of meta-analyses already exist for determining the diagnostic accuracy of FFR-CT (compared to invasive FFR as the reference standard). However, although knowing the overall diagnostic accuracy of FFR-CT is reassuring, in clinical practice a clinician knows not only whether the FFR-CT is positive or negative, but also its actual value. The purpose of this study was to provide clinicians a means of interpreting the diagnostic accuracy of any individual FFR-CT result that may be received in clinical practice.

MedicalResearch.com: What are the main findings?

Response: The main finding of this study is that the diagnostic accuracy of FFR-CT varies markedly across the spectrum of disease. For vessels with FFR-CT above 0.90, 98% met the invasive FFR guideline criterion for deferral. At the other end of the spectrum, for vessels with FFR-CT below 0.60, 86% met the invasive FFR guideline criterion for stenting. However, in between, FFR-CT gives less certainty as to whether the invasive FFR will meet the stenting criterion or not.

MedicalResearch.com: What should readers take away from your report?

Response: Readers can combine the findings of our study with patient specific factors in order to judge when the cost and risk of an invasive angiogram may safely be avoided. Because we now have a more complete picture of what different levels of FFR-CT mean in terms of invasive FFR, it is apparent that a single cut-off value for FFR-CT in deciding on invasive coronary angiography need not always apply. For example, in the asymptomatic patient, further investigations may not be desirable even if an FFR-CT still left a substantial possibility of a positive invasive FFR. Conversely, in the symptomatic patient, the patient and clinician would likely pursue invasive angiography unless the possibility of a positive FFR is very remote.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Response: This study adopted novel methodology to ascertain the probability that both FFR-CT and invasive FFR agreed on the functional classification of a stenosis, for any given individual FFR-CT value. This type of analysis could be used to determine if further iterative versions of the FFR-CT software translate into improved diagnostic performance, particularly in more intermediate disease severities. 

MedicalResearch.com: Is there anything else you would like to add?

Response:

MedicalResearch.com: Thank you for your contribution to the MedicalResearch.com community.

Citation:

Cook CM, Petraco R, Shun-Shin MJ, Ahmad Y, Nijjer S, Al-Lamee R, Kikuta Y, Shiono Y, Mayet J, Francis DP, Sen S, Davies JE. Diagnostic Accuracy of Computed Tomography–Derived Fractional Flow Reserve A Systematic Review . JAMA Cardiol. Published online May 24, 2017. doi:10.1001/jamacardio.2017.1314

Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.

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MRI Guided Prostate Biopsies Can Improve Care and Reduce Costs

MedicalResearch.com Interview with:

Vikas Gulani, MD, PhD Director, MRI, UH Cleveland Medical Center Associate Professor, Radiology, CWRU School of Medicine

Dr. Gulani

Vikas Gulani, MD, PhD
Director, MRI, UH Cleveland Medical Center
Associate Professor, Radiology, CWRU School of Medicine

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: We wanted to learn if performing MR before prostate biopsy, followed by MR guided strategies for biopsy, are cost effective for the diagnosis of prostate cancer in men who have not previously undergone a biopsy and who have a suspicion of prostate cancer.

The most significant findings are as follows:

We found that all three MR guided strategies for lesion targeting (cognitive targeting, MR-ultrasound fusion targeting, and in-gantry targeting) are cost effective, as the increase in net health benefits as measured by addition of quality adjusted life years (QALY), outweigh the additional costs according to commonly accepted willingness to pay thresholds in the United States.

Cognitive targeting was the most cost effective. In-gantry biopsy added the most health benefit, and this additional benefit was cost-effective as well.

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No Magic Age To Stop Performing Screening Mammograms

MedicalResearch.com Interview with:
Cindy S. Lee, MD

Department of Radiology and Biomedical Imaging
University of California, San Francisco, San Francisco
Now with Department of Radiology
NYU Langone Medical Center, Garden City, New York

MedicalResearch.com: What led you and colleagues to conduct this study?

Response: I am a breast imager. I see patients who come in for their screening mammograms and I get asked, a lot, if patients aged 75 years and older should continue screening, because of their age. There is not enough evidence out there to determine how breast cancer screening benefits women older than 75. In fact, all previously randomized trials of screening mammography excluded people older than 75 years.

Unfortunately, age is the biggest risk factor for breast cancer, so as patients get older, they have higher risks of developing breast cancer. It is therefore important to know how well screening mammography works in these patients.

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Cardiac Magnetic Resonance Can Exclude Clinically Relevant Coronary Artery Disease

MedicalResearch.com Interview with:

Pr. Juerg Schwitter MD Médecin Chef Cardiologie Directeur du Centre de la RM Cardiaque du CHUV Centre Hospitalier Universitaire Vaudois - CHUV Suisse

Pr. Schwitter

Pr. Juerg Schwitter MD
Médecin Chef Cardiologie
Directeur du Centre de la RM Cardiaque du CHUV
Centre Hospitalier Universitaire Vaudois – CHUV
Suisse 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Coronary artery disease (CAD) is still one of the leading causes of death in the industrialized world and as such, it is also an important cost driver in the health care systems of most countries. For the European Union, the estimated costs for CAD management were 60 billion Euros in 2009, of which approximately 20 billion Euros were attributed to direct health care costs (1). In 2015, the total costs of CAD management in the United States were estimated to be 47 billion dollars (2).

Substantial progress has been achieved regarding the treatment of CAD including drug treatment but also revascularizations procedures. There exists a large body of evidence demonstrating myocardial ischemia as one of the most important factors determining the patient’s prognosis and reduction of ischemia has been shown to improve outcome.

On the other hand, techniques to detect CAD, i.e. relevant myocardial ischemia, were insufficient in the past. Evaluation of myocardial perfusion by first-pass perfusion cardiac magnetic resonance (CMR) is now closing this gap (3) and CMR is recommended by most international guidelines for the work-up of known or suspected CAD (4,5).

Still, a major issue was not clarified until now, i.e. “how much ischemia is required to trigger revascularization procedures”. Thus, this large study was undertaken to assess at which level of ischemia burden, patients can be safely deferred from revascularization and can be managed by risk factor treatment only. Of note, this crucial question was addressed in both, patients with suspected CAD but also in patients with known (and sometimes already advanced) CAD, thereby answering this question in the setting of daily clinical practice.

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Doctors Continue To Order Mammograms Outside of Current Age Guidelines

MedicalResearch.com Interview with:
Archana Radhakrishnan MD MHS
Division of General Internal Medicine
Johns Hopkins University
Baltimore, Maryland

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: We were interested in understanding the current practice trends in breast cancer screening recommendations by doctors in light of the guideline changes.  We performed a national survey of primary care providers and gynecologists asking about their breast cancer screening practices.

We found that a large number of doctors recommend breast cancer screening to younger and older women—upwards of 80% of doctors recommend it for younger women (ages 40-44) and almost 70% for women 75 and older.  But this varies by the type of doctor that a woman see.  Gynecologists were, in general, more likely to recommend routine mammograms.

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Ischemic Stroke: Collateral Blood Vessels Detected by Arterial Spin Labeling MRI Correlates With Good Neurological Outcome

MedicalResearch.com Interview with:
Jalal B. Andre M.D., D.A.B.R.®

Drector of neurological MRI and
MRI safety officer at Harborview Medical Center
University of Washington 

MedicalResearch.com: What is the background for this study?

Response: Acute ischemic stroke (AIS) patients with good collaterals have better clinical outcomes. AIS is characterized by an ischemic penumbra, a region of salvageable brain tissue, that surrounds a core of irreversible ischemic infarct. The penumbra is tenuously perfused by collateral blood vessels which, if extensive enough, can maintain penumbral perfusion, improving the odds that a larger volume of brain tissue will survive. Standard, first-line methods for evaluating collaterals in the acute setting include CT angiography, MR angiography, and (less commonly) digital subtraction angiography. Arterial spin labeling (ASL) is an emerging MRI technique that assesses cerebral perfusion. Its advantages include relatively short scan time (4-6 minutes), lack of ionizing radiation, and independence from an exogenous contrast agent (contraindicated in patients with impaired renal function or documented sensitivity). Collaterals can be identified within ASL images as foci of curvilinear hyperintensity bordering regions of hypoperfusion. We sought to explore a novel relationship between the presence of ASL collaterals (ASLc) and neurological outcome in acute ischemic stroke patients.

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