EXTENSION OF SEARCH THAT BEGAN WITH IDENTIFICATION OF WHITE MATTER HYPERINTENSITIES IN MRI ON 19 YR. OLD --  (suspect EMF/EMR exposure due to sleeping close to electric clock....).......see access info to original commentary (Omega site) and study connecting white matter hyperintensities with immune function below this Cerebral Blood study (2002)....."AGING" continues to be "a keyword" in regard to harm due to close proximity to EMF/EMR.....jcm  - 12 9 06.....

J Neuropsychiatry Clin Neurosci 16:83-92, February 2004
© 2004 American Psychiatric Press, Inc.

Cerebral Blood Volume in T2-Weighted White Matter Hyperintensities Using Exogenous Contrast Based Perfusion MRI

Perminder Sachdev, M.D., FRANZCP, Ph.D., Wei Wen, Ph.D., Ron Shnier, MBBS, FRACR and Henry Brodaty, M.D., FRACP, FRANZCP

Received April 24, 2002; revised October 8, 2002; accepted November 6, 2002. From the Department of Neuropsychiatry, University of New South Wales, Sydney, & Clinical Director, Neuropsychiatric Institute, The Prince of Wales Hospital, Randwick, New South Wales 2031, Australia; the Neuropsychiatric Institute, the Prince of Wales Hospital, Randwick, New South Wales 2031, Australia; St George MRI, St George Hospital, Kogarah, Sydney; the Department of Psychogeriatrics, University of New South Wales, and Academic Department of Old Age Psychiatry, Prince of Wales Hospital, Randwick. Address correspondence to Dr Sachdev, Neuropsychiatric Institute, The Prince of Wales Hospital, Barker Street, Randwick NSW 2031, Australia p.sachdev@unsw.edu.au (E-mail).

ABSTRACT

 
We used perfusion weighted magnetic resonance imaging (MRI) to determine relative regional cerebral blood volume (rCBV) in regions of white matter hyperintensity (WMH) in 28 elderly stroke patients and 27 healthy comparison subjects, using T2-weighted fluid-attenuated inversion recovery (FLAIR) sequence MRI for anatomical localization and bolus gadolinium-DTPA tracking for perfusion weighted imaging. We found that WMHs had significantly lower rCBV than contralateral normal WMH, irrespective of size or group membership, and rCBV was significantly related to the size of the WMH. For the larger WMHs, there was a significant increase in rCBV from inner core to outer ring. The findings suggest hemodynamic perturbation in the microvasculature of hyperintense regions, which becomes greater as the size of the WMH increases. This is equally applicable to stroke patients and healthy older individuals.

INTRODUCTION

Foci of high signal intensity on T2-weighted magnetic resonance imaging (MRI) in white matter are common findings in the brains of asymptomatic elderly individuals.^1–2 The corresponding appearance on computed tomography (CT) of extensive white matter hyperintensities (WMHs) is a periventricular lucency, referred to as leukoaraiosis.³ White matter hyperintensities have been associated with cerebral ischemia, multiple sclerosis, hydrocephalus, trauma, inflammatory disease, radiation injury, amyloidosis, and other causes, and their etiology is varied.⁴ Their pathology is similarly varied with reports of normal findings to complete infarction.^5–8

^{[emphasis added by Joanne C. Mueller ...12 9 06.....]}

The high frequency of WMHs in the elderly, with rates of nearly 90% being reported in some healthy samples,⁹ has raised the issue of their functional relevance. Studies examining the effects of WMHs on cognition have not been consistent. When WMHs are extensive, patients are described as having frontal-subcortical patterns of cognitive deficits.¹⁰ The neuropsychological deficits with less extensive WMHs are likely to be subtle, and a threshold effect has been argued.¹¹ White matter hyperintensities are commonly associated with stroke and risk factors of stroke such as age, arterial hypertension, cardiac disease, and diabetes mellitus.¹² However, the impact of WHMs on dementia remains open to dispute.¹³

Some evidence for the functional significance of WMHs has come from studies of brain perfusion and glucose metabolism. The presence of subcortical hyperintense lesions has been associated with reduced cerebral blood flow (CBF) in the cortex, using positron emission tomography (PET) and single photon emission computed tomography (SPECT) studies.^14–18 These studies are usually conducted in cases with severe leukoaraiosis or deal with global effects of the lesions, which are limitations. The relatively poor resolution of these functional imaging techniques does not permit the significance of smaller WMHs to be examined.

Perfusion imaging with MRI is a new technique that combines the high resolution of MRI with the ability to measure regional cerebral blood volume (rCBV) and flow (rCBF).¹⁹ It, therefore, enables the measurement of rCBV in individual WMHs irrespective of their size. In this study, we use perfusion imaging with MRI to examine rCBV in WMHs in stroke patients and comparison subjects. We set out to address the following questions: 1) Is rCBV abnormal in the regions of WMHs? 2) If yes, is this abnormality a feature of all WMHs, irrespective of their sizes? 3) In large WMHs, is there a gradient of rCBV, with the inner core being more ischemic? 4) Do WMHs have a penumbra of reduced rCBV? 5) Is the perfusion of WMHs in healthy subjects less abnormal than that of stroke patients, or are WMHs similar in their perfusion irrespective of the extent of cerebrovascular disease in an individual? ^{..............}

^{NOTE:   THIS ARTICLE IS MUCH LONGER ....PURPOSE IN THIS INSTANCE IS TO USE THE STUDY TO SUPPORT WHITE MATTER HYPERINTENSITIES AND ITS RELATIONSHIP TO NOT ONLY MIGRAINES BUT ALSO TO OTHER HEALTH PROBLEMS WELL-KNOWN TO BE ASSOCIATED WITH LOW LEVEL, CHRONIC, PROLONGED EMF-EMR EXPOSURES.     ALSO, THIS STUDY WAS CONDUCTED IN 2002 AND PUBLISHED IN  2004.....ASSUME MUCH HAS BEEN LEARNED SINCE 2002........Joanne Mueller .....12-9-06}

^{Access info for entire article:  http://neuro.psychiatryonline.org/cgi/content/full/16/1/83}

^{See also Omega listing  below re email to Dr. Marilyn Albert (a member of the Alzheimers Association Advisory Board Task Force   -}   

“The question Is not” ;; If cell phone radiation can cause DNA damage?!?!
 Images exist that prove without question it can! ;; “The question is”
Can your body repair DNA damage ;;without mutating genes?

from:  http://cellphonesafety.wordpress.com/