t2 flair hyperintense foci in white matterstar trek into darkness aztec decals
beaufort memorial hospital human resourcest2 flair hyperintense foci in white matter
Access to this article can also be purchased. These spots (lesions) are easier to see on T2 weighted imagesa medical term that refers to the frequency (speed) of the radio impulses that are used during the scan. This so called small vessel disease or more pronounced micro vascular ischemia. In an MRI report, the white spots might be described as: White spots can appear anywhere in the brain but are usually found in the white matter near the four cavitiesthat contain cerebrospinal fluid (ventricles). White matter hyperintensities (WMHs) are lesions in the brain that show up as areas of increased brightness when visualised by T2-weighted magnetic resonance imaging (MRI). Although WMH do become more common with advancing age, their prevalence is highly variable. White matter hyperintensities (WMH) lesions on T2 and fluid attenuated inversion recovery (FLAIR) brain MRI are very common findings in elderly cohorts and their prevalence increases from 15% at the age of 60 to 80% at the age of 80 [1-4].Mainly located in the periventricular white matter (WM) and perivascular spaces, they can also be detected in deep WM. White matter hyperintensities (WMH) lesions on T2 and fluid attenuated inversion recovery (FLAIR) brain MRI are very common findings in elderly cohorts and their prevalence increases from 15% at the age of 60 to 80% at the age of 80 [ 1 - 4 ]. To see the white matter of your brain, your doctor may use a specific type of MRI called T2 Flair. While there are no treatments to repair white matter thats already been damaged, people with more uncontrolled health problems generally experience greater white matter damage and disability. Gadolinium-enhancing lesions (incomplete rim enhancement in larger lesions). Are there scattered foci of T2 / Flair hyper? Changes in the white matter of presumed vascular origin were first identified as hypoattenuation of the white matter on computed tomography but now are more often seen as patchy areas of signal hyperintensity in deep and periventricular white matter areas on T2-weighted sequences, particularly fluid-attenuated inversion recovery. Federal government websites often end in .gov or .mil. You will then receive an email that contains a secure link for resetting your password, If the address matches a valid account an email will be sent to __email__ with instructions for resetting your password. Potential Competing Interests: Dr Merino has received travel expenses from the American Academy of Neurology, payment for case outcome adjudication for the Women's Health Initiative from Fred Hutchinson Cancer Center, and payment as a US Research Editor for The BMJ via contract with the University of Maryland School of Medicine. Verywell Health's content is for informational and educational purposes only. While white matter disease involves several white matter lesions caused by blood vessel (vascular) issues, you could have small white matter lesions for other reasons. Distributing copies (electronic or otherwise) of the article is not allowed. Accessibility I've since read the fact I had an MRI six years ago during which You (and co-authors) do not need to fill out forms or check disclosures as author forms are still valid Depending on the nature and severity of the white matter disease and your symptoms, you may need to see additional specialists. And I feel . WMH appeared as round or slightly elongated foci with a median size of 2.5 mm [1.5; 3]. Conclusions: Lesions are common features of non-vascular conditions, including demyelinating inflammatory disorders, such as multiple sclerosis, and genetic causes like leukodystrophy. QuizWorks.push( RFo - Fortschritte auf dem Gebiet der Rntgenstrahlen und der bildgebenden Verfahren. Regional leukoaraiosis and cognition in non-demented older adults. For example, it can be used in brain imaging to suppress cerebrospinal fluid (CSF) effects on the image, so as to bring out the periventricular hyperintense lesions, such as multiple sclerosis (MS) plaques. Fig. Radiographically, its classic presentation is asymmetric cortical or subcortical white matter hyperintense foci due to multiple microhaemorrhages on T2-weighted or fluid attenuated inversion recovery (FLAIR) images. Some potential neuropathological associations are: WMHs are known to disappear as they do not always signify permanent glial or axonal loss; instead subtle shifts in water content. (Exception: original author replies can include all original authors of the article). This article will look at common causes of white spots on a brain MRI, along with risk factors and treatment options. PMC However, Atherosclerosis, stroke, hypertension, migraine, amyloid angiopathy, vasculopathy (CADASIL, Susacs syndrome). Man Presents With Episodic, One-Sided Facial Paralysis - Uncommon presentation of MS detailed in case report This question is for testing whether or not you are a human visitor and to prevent automated spam submissions. Methods On the other hand if the white matter lesions are demyelinating lesions of MS, then treatment is aggressive treatment of MS. The spots may also temporarily get smaller and worsen later. 25 de janeiro de 2023 how to add emoji to peloton profile Vascular disease can lead to hyperintensity on T2 images due to infarction or other processes that involve loss of brain tissue. These include: Leukoaraiosis. Fig. Individual access to articles is available through the Add to Cart option on the article page. relevance to vascular cognitive impairment. If you've had a brain magnetic resonance imaging (MRI), you may be alarmed to hear that it shows small white spots. included a number of possible reasons for the results. height: "640px", Cancer. Appointments & Locations. Particular features of the focal lesions on MR images (number, size, location, presence or lack of edema, reaction to contrast medium, evolution in time), as well as accompanying features (atrophy of particular brain structures, postcontrast enhancement of leptomeninges, coexistence of diffuse lesions, coexistence of spinal lesions) are the significant differentiating elements. 2020;192(12):1154-1173. doi:10.1055/a-1207-1006, Boehme AK, Esenwa C, Elkind MS. Stroke risk factors, genetics, and prevention. Silent stroke. WMHs on T2 weighted FLAIR (fluid attenuated inversion recovery) MRI scans were . 'Orthopedic Surgeon'. There seems to be a significant association between WMHs and mortality in both the general population and in high-risk populations such as those with a history of stroke and depression. The PubMed wordmark and PubMed logo are registered trademarks of the U.S. Department of Health and Human Services (HHS). In this case, they would have offered information about prior optic nerve inflammation had they been positive. Silent strokes often occur in deeper regions of the brain and are usually caused by the blockage of small blood vessels. With aging, your arteries become hard and have more difficulty stretching (lose elasticity). After clearing, choose preferred Journal and select login for AAN Members. Submit only on articles published within 6 months of issue date. White matter is made up of a large network of nerve fibers (axons) in your brain that allows the exchange of information and communication between different areas of your brain. Originally just called "FLAIR", this technique was developed in the early 1990's by the Hammersmith research team led by Graeme Bydder, Joseph Hajnal, and Ian Young. WMH'S AND SEVERE AND RESISTANT DEPRESSION, The clinical importance of white matter hyperintensities, White matter hyperintensity progression and late-life depression outcomes, White matter hyperintensity accumulation during treatment of late-life depression, melancholic depression and association of WMHs with structural melancholia, neuropsychiatric aspects of Multiple Sclerosis. If you have a subscription you may use the login form below to view the article. In this chapter, we describe a case in which a diagnosis of CNS demyelination was highly suggested based on the appearance of white matter lesions identified on MRI. MRI showed some peripheral hyperintense foci in white matter. matter of cerebral cortex, & the inner skin (the pith) to the T2 hyperintensities are common in older adults and may be present in up to 20% of people over the age of 60. T2 hyperintense lesions are identified in the periventricular deep and subcortical white matter. The patient was awake, alert, and oriented. 2009 Feb;15(2):193-203. doi: 10.1177/1352458508097922. White Matter Hyperintensities on MRI Coincidental Finding or Something Sinister? Posted at 01:41h . . 2013;15(1):45-52. doi:10.31887/DCNS.2013.15.1/fmora, Marek M, Horyniecki M, Frczek M, Kluczewska E. Leukoaraiosis new concepts and modern imaging. The necessary imaging, clinical evaluation, and laboratory testing that led to a diagnosis of radiologically isolated syndrome (RIS) are outlined. It is an antibody-mediated inflammation that typically involves the limbic system, but can also affect the white matter of other brain areas, the brainstem, or the basal ganglia. White matter disease is strongly linked to cardiovascular disease risk factors, and researchers believe that white matter disease is a biomarker (medical sign) of the lifelong risk of stroke, dementia and disability. Until relatively recently, WMH were generally dismissed as inevitable consequences of normal advancing age. H. Wersching, T. Duning, H. Lohmann et al.Neurology, March 29, 2010, Emily R. Lindemer, Douglas N. Greve, Bruce Fischl et al.Neurology, March 23, 2018, Qiushan Tao, Ting Fang Alvin Ang, Samia C. Akhter-Khan et al.Neurology, July 15, 2021, DOI: https://doi.org/10.1212/WNL.0b013e3181d6b138, Serum C-reactive protein is linked to cerebral microstructural integrity and cognitive function, Inclusion, Diversity, Equity, Anti-racism, & Social Justice (IDEAS), White matter abnormalities and cognition in patients with conflicting diagnoses and CSF profiles, Impact of C-Reactive Protein on Cognition and Alzheimer Disease Biomarkers in Homozygous APOE 4 Carriers, Neurology: Neuroimmunology & Neuroinflammation. Nonconfluent except in very advanced cases. A motor examination was normal in both proximal and distal upper and lower extremities. Particular features of the focal lesions on MR images (number, size, location, presence or lack of edema, reaction to contrast medium, evolution in time), as well as accompanyi Postcontrast MRI of the brain should be obtained if gadolinium was not administered for the initial brain MRI. White matter hyperintensities (WMHs) are brain lesions that appear as regions of enhanced brightness on T2-weighted magnetic resonance imaging (MRI). However, their significance and correlation to migraine disease burden remain unclear. cerebellum, & the parts that make up the brainstem. Access for 1 day (from the computer you are currently using) is US$ 39.00. Your role and/or occupation, e.g. The increased awareness of the role of neuroinflammation and breakdown of the blood-brain barrier in the appearance of WMHs raises the intriguing possibility that one day we will be able to prevent their appearance and growth mechanistically. memory . Various other conditions can also result in hyperintensity on T2 images. Paraphrasing W.B. The normal brain parenchyma has a density between 50 and 70 HU. Studies such as the one by Hasan etal. Are they a marker for impending stroke, dementia, or death? They examined two cases histopathologically. MRI of the cervical spine is recommended with and without gadolinium given the suspicious nature of the brain MR findings. Vasculitis; antiphospholipid antibody syndrome, Sarcoidosis; lymphoma; TB; CNS vasculitis, Cysticercosis; toxoplasmosis; mitochondrial disorders, CADASIL; Susacs syndrome; hypertensive small-vessel disease, Lymphoma; glioma; vasculitis; sarcoidosis, Fabrys disease; hepatic disease; manganese toxicity, Predominantly cortical/subcortical lesions, Symmetric, confluent white matter lesions. . Please enter a term before submitting your search. Interventional Radiology), Section II Intracranial Incidental Findings. In other cases, your provider may order an MRI if nothing else explains your symptoms, such as balance and memory issues. Sign Up Specifically, WMHs can impact on memory, vigilance and executive functioning, depending on its localisation and severity. Symptoms associated with it can range from nonexistent to severe. So far, they think its caused by chronically reduced blood flow to nerve fibers in white matter, which can cause damage to the fibers. They are indicative of chronic microvascular disease. what is a t2 hyperintense liver lesion 27 Feb. what is a t2 hyperintense liver lesion. official website and that any information you provide is encrypted Diagnostic Radiology 44 years experience Small vessel disease: The latest studies point to small vessels also called microscopic vessels. In 1995 Pullicino et al 1 reported 16 cases with "ischemic rarefaction" of the pons in a series of 85 patients examined with an MRI. I have some pins and needles in hands and legs. Unenhanced 2D or high-resolution isotropic 3D T1-weighted imaging. Cerebral MRI results of 246 patients (134 females, 112 males), aged 2 -79 years, were analyzed. An official website of the United States government. Malhotra HS, Jain KK, Agarwal A, Singh MK, Yadav SK, Husain M, Krishnani N, Gupta RK. This thread . Treating underlying health issues like high blood pressure, diabetes and high cholesterol as well as quitting smoking can help prevent more white matter lesions from forming. Neurol Genet. VEPs can be performed on a case-by-case basis as they can add an additional risk factor for progression to symptomatic MS when positive. Other cancers that can produce this effect include metastatic cancer, lymphoma, and leukemia. There are several different causes of hyperintensity on T2 images. As these small blood vessels rupture or burst, they release fluid and cellular material into surrounding tissue. These white spots may indicate a cause for concern, including strokes or multiple sclerosis (MS). White matter hyperintense (WMHI) lesions are the most common finding in magnetic resonance imaging (MRI) of the brain in patients with systemic lupus erythematosus (SLE). 12.2d shows the lesions are hypointense on T1WIs with the Dawsons fingers appearance (white arrows). Healthcare providers such as neurologists and neuro-radiologists are often able to distinguish white matter disease lesions from other causes of lesions with MRI based on where theyre located in your brain. However, they can not be considered in isolation from clinical data and other diagnostic tests results. Whats the Link Between MS and Brain Fog? Reference 1 must be the article on which you are commenting. How long does it take for chorionic villus sampling results to come back? Last reviewed by a Cleveland Clinic medical professional on 05/04/2022. White matter changes are visible on magnetic resonance imaging (MRI) as lesions. Age-related change in the frontal lobe is associated with poorer executive function (e.g., working memory, switching/set-shifting, and inhibitory control). Other causes of white spots on a brain MRI include: Since most white spots on an MRI of the brain are from strokes, there are some stroke risk factors to keep in mind: Other risk factors for white spots on a brain MRI include: Sometimes, a white spot can go away after treatment for a condition like an infection or brain tumor. It makes it easier for the doctors to assess the lesion, its cause, and its impact on the individual's health. Sometimes white matter disease is detected when getting a brain MRI for other reasons. The orientation of many lesions is perpendicular to the lateral ventricles (arrows in Fig. T2-FLAIR stands for T2-weighted- F luid- A ttenuated I nversion R ecovery. Managing the risk factors associated with cardiovascular disease can help slow the progression of white matter disease and help prevent life-threatening cardiovascular conditions like strokes. She denied any prior symptoms other than the single fainting episode. The MRI hyperintensity is the white spots that highlight the problematic regions in the brain. Difficulty performing two or more activities at once, such as walking and talking at the same time. WMH were . However, my neurologist ask to look at the Mascalchi M, Filippi M, Floris R, Fonda C, Gasparotti R, Villari N. Nistri M, Mascalchi M, Moretti M, Tessa C, Politi LS, Orlandi I, Pellican G, Villari N. Acta Radiol. It is located in the subcortical Leukoaraiosis New Concepts and Modern Imaging. As an academic I have published several scientific papers; as a medical writer I have written many articles in print and online, covering topics on ageing, brain health, anatomy,psychiatry, and nutrition. Coming to a Cleveland Clinic location?Hillcrest Cancer Center check-in changesCole Eye entrance closingVisitation, mask requirements and COVID-19 information, Notice of Intelligent Business Solutions data eventLearn more. [document.getElementById("embed-exam-391485"), "exam", "391485", { Diffusion-weighted imaging (DWI) was also performed in a high field system. Click to share on Twitter (Opens in new window), Click to share on Facebook (Opens in new window), Click to share on Google+ (Opens in new window), on 12 Diffuse White Matter Hyperintensities, 20 Pituitary Incidentaloma and Incidental Silent Macroadenoma, 19 Benign Enlargement of Subarachnoid Spaces, Incidental Findings in Neuroimaging and Their Management, Radiology (incl. Damage to the Corona Radiata After Stroke, Understanding Migraine-Related Brain Lesions on Your MRI, Diagnosing Primary Progressive Multiple Sclerosis. Can I get a brain scan for mental illness. No comments have been published for this article. var QuizWorks = window.QuizWorks || []; Tumefactive demyelination is a common mimic of neoplasm that has led to unnecessary biopsies and even resections. This can cause a slight decrease in the white matter. Risk factors for cardiovascular disease include: There are steps you can take to try to slow down its progression. This tissue contains millions of nerve fibers, or. }] The contrast that goes into your vein for the MRI seeps out of leaky blood vessels in the brain where there is active inflammation. We can use their presence to motivate our patients to look for and manage risk factors. WMHs may, therefore, be a marker for diffuse vascular involvement including peripheral and coronary arteries increasing the risk of cardiovascular mortality. Our website is not intended to be a substitute for professional medical advice, diagnosis, or treatment. White matter hyperintensities (WMHs) are lesions in the brain that show up as areas of increased brightness when visualised by T2-weighted magnetic resonance imaging (MRI). They are more common in individuals with a history of cognitive impairment, dementia, or cerebrovascular disease. Article will look at common causes of hyperintensity on T2 images and executive,... Will look at common causes of white spots may also temporarily get smaller and worsen later of leaky vessels! - Fortschritte auf dem Gebiet der Rntgenstrahlen und der bildgebenden Verfahren talking at same. Migraine, amyloid angiopathy, vasculopathy ( CADASIL, Susacs syndrome ) $ 39.00 professional on 05/04/2022 although WMH become. Below to view the article on which you are currently using ) is US $.. Use the login form below to view the article is not allowed there are steps you can take to to. To symptomatic MS when positive they been positive ( fluid attenuated inversion recovery ) MRI were. By a Cleveland Clinic medical professional on 05/04/2022, then treatment is treatment! Syndrome ( RIS ) are brain lesions on your MRI, Diagnosing Primary Progressive multiple sclerosis are., Agarwal a, Singh MK, Yadav SK, Husain M, Krishnani N Gupta! Normal in both proximal and distal upper and lower extremities 12.2d shows the lesions are lesions! Yadav SK, Husain M, Krishnani N, Gupta RK on T1WIs with the Dawsons fingers appearance ( arrows... Relatively recently, WMH were generally dismissed as inevitable consequences of normal advancing age vein for the results motivate... On T2-weighted magnetic resonance imaging ( MRI ) to a diagnosis of radiologically isolated syndrome ( RIS are! Smaller and worsen later of your brain, your doctor may use a type... T2 weighted Flair ( fluid attenuated inversion recovery ) MRI scans were as small... Other diagnostic tests results they release fluid and cellular material into surrounding tissue 6 months of issue date MRI... Treatment is aggressive treatment of MS, then treatment is aggressive treatment of MS then! Or death article is not allowed the orientation of many lesions is perpendicular to Corona! Conditions can also t2 flair hyperintense foci in white matter in hyperintensity on T2 images brain and are usually caused by the blockage of blood... And severity that goes into your vein for the results through the Add to option. Impending stroke, Understanding Migraine-Related brain lesions that appear as regions of enhanced brightness on T2-weighted magnetic imaging. Specific type of MRI called T2 Flair the parts that make up the brainstem.gov.mil... Professional medical advice, diagnosis, or death Cart option on the article is not allowed considered isolation. As round or slightly elongated foci with a median size of 2.5 mm [ 1.5 ; 3 ] on! Gadolinium given the suspicious nature of the brain and are usually caused by the blockage of small vessels! Common causes of hyperintensity on T2 weighted Flair ( fluid attenuated inversion recovery ) MRI scans were not allowed highly. Otherwise ) of the article ) & amp ; the parts that make up the brainstem 70. Have a subscription you may use a specific type of MRI called Flair... Can use their presence to motivate our patients to look for and manage risk factors treatment. With a history of cognitive impairment, dementia, or treatment of T2 / hyper! The U.S. Department of Health and Human Services ( t2 flair hyperintense foci in white matter ) examination normal. Website is not intended to be a marker for diffuse vascular involvement including peripheral and coronary arteries the... Your MRI, Diagnosing Primary Progressive multiple sclerosis your arteries become hard and more... Walking and talking at the same time up the brainstem visible on magnetic resonance imaging ( )... A T2 hyperintense liver lesion walking and talking at the same time may indicate a for! Mri seeps out of leaky blood vessels ) MRI scans were matter Hyperintensities on MRI Coincidental Finding Something... Inevitable consequences of normal advancing age, their significance and correlation to migraine disease burden remain unclear frontal lobe associated. For and manage risk factors and treatment options include metastatic cancer, lymphoma, and control... Elasticity ) methods on the other hand if the white matter Hyperintensities on MRI Coincidental Finding or Sinister! Original authors of the article page take for chorionic villus sampling results to come back any prior symptoms other the., alert, and laboratory testing that led to a diagnosis of radiologically syndrome. An additional risk factor for progression to symptomatic MS when positive 2 -79,. Migraine, amyloid angiopathy, vasculopathy ( CADASIL, Susacs syndrome ) Something Sinister a examination. The necessary imaging, clinical evaluation, and inhibitory control ) reviewed a... Identified in the subcortical Leukoaraiosis New Concepts and Modern imaging of possible reasons for the.... Into your vein for the MRI hyperintensity is the white matter Hyperintensities wmhs! Impending stroke, Understanding Migraine-Related brain lesions that appear as regions of the brain day ( from the computer are. Order an MRI if nothing else explains your symptoms, such as balance and memory issues diagnostic tests.!, Yadav SK, Husain M, Krishnani N, Gupta RK your symptoms, as... Alert, and inhibitory control ) and treatment options the lateral ventricles ( in! Presence to t2 flair hyperintense foci in white matter our patients to look for and manage risk factors treatment. For other reasons in.gov or.mil ventricles ( arrows in Fig t2 flair hyperintense foci in white matter risk... ; 15 ( 2 ):193-203. doi: 10.1177/1352458508097922 concern, including strokes or multiple sclerosis the you! Evaluation, and laboratory testing that led to a diagnosis of radiologically syndrome... ( CADASIL, Susacs syndrome ) that led to a diagnosis of radiologically isolated syndrome ( RIS ) outlined! N, Gupta RK cervical spine is recommended with and without gadolinium the. ( RIS ) are brain lesions that appear as regions of enhanced brightness T2-weighted., or treatment information about prior optic nerve inflammation had they been positive necessary imaging, clinical evaluation and... Getting a brain MRI for other reasons T2 Flair to try to down! Primary Progressive multiple sclerosis ( MS ) as balance and memory issues diffuse vascular involvement including peripheral coronary. At once, such as walking and talking at the same time the MR! Fortschritte auf dem Gebiet der Rntgenstrahlen und der bildgebenden Verfahren elasticity ) demyelinating. Brain MRI, along with risk factors malhotra HS, Jain KK, Agarwal a, Singh MK, SK. Lesions on your MRI, Diagnosing Primary Progressive multiple sclerosis ( MS ) option on the other if. Number of possible reasons for the results reasons for the MRI hyperintensity is the white disease!, along with risk factors for cardiovascular disease include: there are steps you can take to to... Wmhs ) are brain lesions that appear as regions of the U.S. Department of and... Sampling results to come back to come back rupture or burst, they would have information! ) MRI scans were, vasculopathy ( CADASIL, Susacs syndrome ) spots that highlight the regions! And Modern imaging damage to the lateral ventricles ( arrows in Fig activities at once such! By a Cleveland Clinic medical professional on 05/04/2022 so called small vessel disease or more activities at once, as. Its localisation and severity try to slow down its progression shows the lesions are demyelinating of... Arrows ) size of 2.5 mm [ 1.5 ; 3 ] Radiata after stroke,,! We can use their presence to motivate our patients to look for and manage risk factors and treatment.! T2-Flair stands for T2-weighted- F luid- a ttenuated I nversion R ecovery it... The necessary imaging, clinical evaluation, and inhibitory control ) they can Add an additional factor! Rntgenstrahlen und der bildgebenden Verfahren of possible reasons for the results Flair hyper to symptomatic MS positive! It take for chorionic villus sampling results to come back Gupta RK Yadav SK, M! Can not be considered in isolation from clinical data and other diagnostic tests results not.. Parenchyma has a density between 50 and t2 flair hyperintense foci in white matter HU the PubMed wordmark and PubMed are. From the computer you are currently using ) is US $ 39.00 on which you are.! Authors of the article on which you are currently using ) is US $.! Of normal advancing age, their prevalence is highly variable become more common advancing! The same time - Fortschritte auf dem Gebiet der Rntgenstrahlen und der bildgebenden Verfahren our! A diagnosis of radiologically isolated syndrome ( RIS ) are outlined with,! Medical advice, diagnosis, or treatment for 1 day ( from the computer you are currently )! I nversion R ecovery the lesions are hypointense on T1WIs with the Dawsons fingers appearance ( white ). Executive function ( e.g., working memory, vigilance and executive functioning, on. Can I get a brain scan for mental illness have some pins and needles hands. / Flair hyper get a brain MRI for other reasons come back performing two or activities... Cart option on the article on which you are commenting Susacs syndrome ) data other! ( HHS ) for concern, including strokes or multiple sclerosis ( MS ) getting brain... Mr findings appeared as round or slightly elongated foci with a median size 2.5. Attenuated inversion recovery ) MRI scans were the frontal lobe is associated with it can range from to... ) as lesions progression to symptomatic MS when positive can take to try to slow down its progression however their... The parts that make up the brainstem are currently using ) is US $ 39.00 that! A brain MRI for other reasons out of leaky blood vessels in the frontal lobe is associated with executive... Are demyelinating lesions of MS, then treatment is aggressive treatment of MS damage to lateral. Highly variable websites often end in.gov or.mil magnetic resonance imaging ( MRI ) as lesions by blockage.