BMJ 1 Sep 2009 - Brain MRI

Incidental findings on brain magnetic resonance imaging
Aad van der Lugt
BMJ 2009;339 b3107

BMJ 17 Aug 2009

Study finds poor access to radiotherapy services in England
Roger Dobson
BMJ 2009;339 b3278

Incidental findings on brain magnetic resonance imaging: systematic review and meta-analysis
Zoe Morris, William N Whiteley, W T Longstreth, Jr, Frank Weber, Yi-Chung Lee, Yoshito Tsushima, Hannah Alphs, Susanne C Ladd, Charles Warlow, Joanna M Wardlaw, and Rustam Al-Shahi Salman
BMJ 2009;339 b3016

Articles from Neurology

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Tschampa, H J. ; Niehusmann, P ; Marek, M ; Mueller, C -A. ; Kuchelmeister, K ; Urbach, H
MRI in amyloid [beta]-related brain angiitis.
Neurology. 73(3):247, July 21, 2009.

Articles from Anesthesia & Analgesia

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Davidson, Elyad M. MD ; Sklar, Evelyn MD ; Bhatia, Rita MD ; Garcia, Lester MD et al
Magnetic Resonance Imaging Findings After Uneventful Continuous Infusion Neuraxial Analgesia: A Prospective Study to Determine Whether Epidural Infusion Produces Pathologic Magnetic Resonance Imaging Findings
Anesthesia & Analgesia.
Status
Publish Ahead of Print, POST AUTHOR CORRECTIONS, 5 June 2009
Abstract
BACKGROUND: Magnetic resonance imaging (MRI) is considered the preferred diagnostic tool to determine whether postepidural neurologic symptoms are due to hematoma or abscess. However, there is currently no published information regarding the normal appearance of a MRI after a continuous epidural infusion. In this prospective cohort study, we defined the characteristic appearance of MRI findings after uneventful epidural analgesia.METHODS: Thirty women were prospectively enrolled to undergo a lumbar MRI after labor and delivery. The study group consisted of 15 women who received neuraxial analgesia with a combined spinal epidural technique followed by continuous epidural infusion, whereas the control group included 15 women who delivered without receiving neuraxial analgesia. All patients received a MRI within 12 h of delivery via a 1.5T scanner. MRIs were reviewed by two neuroradiologists who were blinded to the patient's study group allocation and asked to document the presence or absence of fluid collection, air collection, or soft tissue abnormalities.RESULTS: There were no radiologically significant fluid collections, hematomas, or mass effects noted on the thecal sac of any of the 30 MRI studies. A small amount of epidural air was seen in 77% of MRI studies after epidural analgesia, but there was no indention on the thecal sac.CONCLUSIONS: The lack of significant collections or mass effects seen in the MRIs of our patients after continuous infusion of epidural analgesia suggests that the presence of these findings in a patient with new neurologic symptoms after administration of epidural analgesia should be considered pathologic and warrant immediate attention.(C) 2009 by International Anesthesia Research Society.

Articles from Spine

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Takatalo, Jani MSc ; Karppinen, Jaro MD, PhD ; Niinimaki, Jaakko MD ; Taimela, Simo et al
Prevalence of Degenerative Imaging Findings in Lumbar Magnetic Resonance Imaging Among Young Adults.
Spine. 34(16):1716-1721, July 15, 2009.
Abstract
Study Design. A cross-sectional imaging study of young adults.Objective. To investigate the prevalence of disc degeneration (DD) and displacement, anular tears, and Modic changes in lumbar magnetic resonance imaging (MRI) among young adults.Summary of Background Data. Although low back pain in young adulthood is common, the prevalence of spinal MRI findings at this age remains virtually unknown.Methods. The study population was a subcohort of the Northern Finland Birth Cohort 1986. Subjects living within 100 km of Oulu (n = 874) were invited to participate in lumbar MRI at 20 to 22 years of age (mean: 21.2 years). Degree of DD, type of Modic changes, and presence of disc bulges, herniations, high intensity zone (HIZ) lesions, and radial tears at all lumbar levels were assessed.Results. Three hundred twenty-five women and 233 men (n = 558) attended the MR imaging. DD was significantly more frequent in men (54% vs. 42%, P = 0.005), as was multiple DD (21% vs. 14%, P = 0.036). The prevalences of disc bulges and radial tears were 25% and 9.1%, respectively, without gender differences. HIZ lesions were more common among women than men (8.6% vs. 4.3%, P = 0.046), whereas herniations were significantly more common among men (5.6% vs. 2.5%, P = 0.047). Only 2 disc extrusions were observed, one in each gender. All degenerative disc findings were more common at the L5-S1 level except HIZ lesions, which were most likely at L4-L5. The prevalence of the Modic changes was 1.4%, without gender difference, type I being more common than type II. Typically, Modic changes were located adjacent to a DD Grade 4 disc and at the 2 lowest levels.Conclusion. Almost half of young Finnish adult aged 21 years had at least one degenerated disc, and a quarter had a bulging disc. Modic changes and disc herniations were, however, relatively rare.(C) 2009 Lippincott Williams & Wilkins, Inc.

Articles from Plastic & Reconstructive Surgery

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Knobloch, Karsten M.D., Ph.D.; Gohritz, Andreas M.D.; Reuss, Ebischa M.D.; Redeker, Joern
Preoperative Perforator Imaging in Reconstructive Plastic Surgery: Current Practice in Germany. [Editorial]
Plastic & Reconstructive Surgery. 124(1):183e-184e, July 2009.


Tabbal, Georges N. B.A.; Bastidas, Nicholas M.D.; Sharma, Sheel M.D.;
Closed Mallet Thumb Injury: A Review of the Literature and Case Study of the Use of Magnetic Resonance Imaging in Deciding Treatment.[Article]
Plastic & Reconstructive Surgery. 124(1):222-226, July 2009.
Abstract
Summary: At present, the literature dedicated to closed mallet thumb injury offers conflicting evidence between conservative and operative approaches. Although conservative treatment is often successful, retraction of the extensor pollicis tendon may lead to improper reattachment and continued deformity. This discussion and case report serve to highlight the use of magnetic resonance imaging as an adjunct in selecting the proper treatment strategy for this injury at initial presentation

MRI and rheumatoid foot

The utility of MRI in predicting radiographic erosions in the metatarsophalangeal joints of the rheumatoid foot: a prospective longitudinal cohort study
Matthew L Mundwiler, Paul Maranian, Douglas H Brown et al
Arthritis Research & Therapy 2009, 11:R94 (22 June 2009)
Provisional PDF http://arthritis-research.com/content/pdf/ar2737.pdf
PubMed http://arthritis-research.com/pubmed/19545417

BMC Medical Imaging

Magnetic resonance imaging after most common form of concussion
Harald Schrader, Dalia Mickeviciene, Rymante Gleizniene et al
BMC Medical Imaging 2009, 9:11 (17 June 2009)
Abstract http://www.biomedcentral.com/1471-2342/9/11/abstract
Provisional PDF http://www.biomedcentral.com/content/pdf/1471-2342-9-11.pdf

Evaluating regional blood spinal cord barrier dysfunction following spinal cord injury using longitudinal dynamic contrast-enhanced MRI
Ilkan Tatar, Peter C Chou, Mohamed M Desouki, Hanaa E Sayed, Mehmet Bilgen
BMC Medical Imaging 2009, 9:10 (11 June 2009)
Abstract http://www.biomedcentral.com/1471-2342/9/10/abstract
Provisional PDF http://www.biomedcentral.com/content/pdf/1471-2342-9-10.pdf

Quantifying coronary sinus flow and global LV perfusion at 3T
Karin Markenroth Bloch, Marcus Carlsson, Hakan Arheden, Freddy Stahlberg
BMC Medical Imaging 2009, 9:9 (11 June 2009)
Abstract http://www.biomedcentral.com/1471-2342/9/9/abstract
Provisional PDF http://www.biomedcentral.com/content/pdf/1471-2342-9-9.pdf

Articles from Neurology

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Fridman, Vera ; Galetta, Steven L. ; Pruitt, Amy A. ; Levine, Joshua M.
MRI FINDINGS ASSOCIATED WITH ACUTE LIVER FAILURE.
Source
Neurology. 72(24):2130-2131, June 16, 2009.

Article from Circulation

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McQuillen, Patrick S. MD
Magnetic Resonance Imaging in Congenital Heart Disease: What to Do With What We See and Don't See? [Editorial]
Circulation. 119(5):660-662, February 10, 2009.

Articles from Anesthesiology

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Practice Advisory on Anesthetic Care for Magnetic Resonance Imaging: A Report by the American Society of Anesthesiologists Task Force on Anesthetic Care for Magnetic Resonance Imaging
Anesthesiology. 110(3):459-479, March 2009.

Articles from Circulation

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Oakes, Robert S. BS; Badger, Troy J. MD; Kholmovski, Eugene G. PhD; Akoum, Nazem et al
Detection and Quantification of Left Atrial Structural Remodeling With Delayed-Enhancement Magnetic Resonance Imaging in Patients With Atrial Fibrillation
Circulation. 119(13):1758-1767, April 7, 2009.
Abstract
Background-: Atrial fibrillation (AF) is associated with diffuse left atrial fibrosis and a reduction in endocardial voltage. These changes are indicators of AF severity and appear to be predictors of treatment outcome. In this study, we report the utility of delayed-enhancement magnetic resonance imaging (DE-MRI) in detecting abnormal atrial tissue before radiofrequency ablation and in predicting procedural outcome.

Methods and Results-: Eighty-one patients presenting for pulmonary vein antrum isolation for treatment of AF underwent 3-dimensional DE-MRI of the left atrium before the ablation. Six healthy volunteers also were scanned. DE-MRI images were manually segmented to isolate the left atrium, and custom software was implemented to quantify the spatial extent of delayed enhancement, which was then compared with the regions of low voltage from electroanatomic maps from the pulmonary vein antrum isolation procedure. Patients were assessed for AF recurrence at least 6 months after pulmonary vein antrum isolation, with an average follow-up of 9.6+/-3.7 months (range, 6 to 19 months). On the basis of the extent of preablation enhancement, 43 patients were classified as having minimal enhancement (average enhancement, 8.0+/-4.2%), 30 as having moderate enhancement (21.3+/-5.8%), and 8 as having extensive enhancement (50.1+/-15.4%). The rate of AF recurrence was 6 patients (14.0%) with minimal enhancement, 13 (43.3%) with moderate enhancement, and 6 (75%) with extensive enhancement (P<0.001). Conclusions-: DE-MRI provides a noninvasive means of assessing left atrial myocardial tissue in patients suffering from AF and might provide insight into the progress of the disease. Preablation DE-MRI holds promise for predicting responders to AF ablation and may provide a metric of overall disease progression.

Articles from Neurology

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Grommes, Christian ; Oghlakian, Roger ; Blackham, Kristina A. ; De Georgia, Michael A.
Corpus callosum dysgenesis limits MRI changes to one hemisphere in status epilepticus
Source
Neurology. 72(10):942, March 10, 2009.

Bonhomme, G R. MD *; Waldman, A T. MD *; Balcer, L J. MD, MSCE; Daniels, A B. et al
Pediatric optic neuritis: Brain MRI abnormalities and risk of multiple sclerosis
Neurology. 72(10):881-885, March 10, 2009.
Abstract
Background: Optic neuritis is often the initial presentation of multiple sclerosis (MS). As established by the Optic Neuritis Treatment Trial, an abnormal baseline brain MRI is a strong predictor of MS after isolated optic neuritis in adults. However, the rate of conversion to MS after optic neuritis in children based upon brain MRI findings is unknown.Methods: We reviewed the medical records of children (<18 p =" 0.04," chop =" Children's" flair =" fluid-attenuated" ms =" multiple" nmo =" neuromyelitis" ontt =" Optic">

Lee, K Y. ; Latour, L L. ; Luby, M ; Hsia, A W. ; Merino, J G. , MPhil; Warach, S
Distal hyperintense vessels on FLAIR: An MRI marker for collateral circulation in acute stroke?
Neurology.
Status
Publish Ahead of Print, POST AUTHOR CORRECTIONS, 11 February 2009
Abstract
Background: Hyperintense vessels (HV) on fluid-attenuated inversion recovery imaging are frequently observed in acute ischemic stroke patients. However, the exact mechanism and clinical implications of this sign have not yet been clearly defined. The features of HV and its relevance to other imaging factors are presented here.Methods: Prominence and location of HV were documented in 52 consecutive patients with middle cerebral artery (MCA) territory infarction, before treatment with IV recombinant tissue plasminogen activator. Pretreatment ischemic lesion volume, perfusion lesion volume, and vessel occlusion were determined in addition to recanalization status and ischemic lesion volume on follow-up imaging. NIH Stroke Scale (NIHSS) was used as a measure of clinical severity.Results: HV distal to arterial occlusion was observed in 73% of patients; more frequent in proximal than distal MCA occlusion patients. Among the 38 patients with proximal MCA occlusion, initial perfusion lesion volume was comparable among patients with different grade distal HV. However, patients with more prominent distal HV had smaller initial, 24-hour, and subacute ischemic lesion volumes and lower initial NIHSS scores.Conclusions: The presence of distal hyperintense vessels before thrombolytic treatment is associated with large diffusion-perfusion mismatch and smaller subacute ischemic lesion volumes in patients with proximal middle cerebral artery occlusion.GLOSSARY: DWI = diffusion-weighted imaging; FLAIR = fluid-attenuated inversion recovery; GRE = gradient recalled echo; HV = hyperintense vessels; MCA = middle cerebral artery; MRA = magnetic resonance angiography; MTT = mean transit time; NIHSS = NIH Stroke Scale; PWI = perfusion-weighted imaging; rt-PA = recombinant tissue plasminogen activator; TE = echo time; TI = inversion time; TIMI = thrombolysis in myocardial infarction; TR = repetition time.

Cadavid, D ; Wolansky, L J. ; Skurnick, J ; Lincoln, J et al
Efficacy of treatment of MS with IFN[beta]-1b or glatiramer acetate by monthly brain MRI in the BECOME study
Neurology.
Status
Publish Ahead of Print, POST AUTHOR CORRECTIONS, 11 March 2009
Abstract
Background: There are no published MRI studies comparing interferon beta 1b (IFN[beta]-1b) and glatiramer acetate (GA) for treatment of relapsing multiple sclerosis (MS).Objective: To compare the efficacy of IFN[beta]-1b and GA for suppression of MS disease activity as evidenced on frequent brain MRI.Methods: A total of 75 patients with relapsing-remitting MS or clinically isolated syndromes were randomized to standard doses of IFN[beta]-1b or GA and followed by monthly brain MRI for up to 2 years with a protocol optimized to detect enhancement. The primary outcome was the number of combined active lesions (CAL) per patient per scan during the first year, which included all enhancing lesions and nonenhancing new T2/fluid-attenuated inversion recovery (FLAIR) lesions. Secondary outcomes were the number of new lesions and clinical exacerbations over 2 years.Results: Baseline characteristics were similar between the groups. The primary outcome showed similar median (75th percentile) CAL per patient per scan for months 1-12, 0.63 (2.76) for IFN[beta]-1b, and 0.58 (2.45) for GA (p = 0.58). There were no differences in new lesion or clinical relapses for 2 years. Only 4.4% of CAL on monthly MRI scans were nonenhancing new T2/FLAIR lesions.Conclusion: Patients with relapsing multiple sclerosis randomized to interferon beta 1b or glatiramer acetate showed similar MRI and clinical activity.GLOSSARY: ARR = annualized relapse rates; BECOME = Betaseron vs Copaxone in Multiple Sclerosis with Triple-Dose Gadolinium and 3-Tesla MRI Endpoints; CAL = combined active lesions; CIS = clinically isolated syndromes; EDSS = Expanded Disability Status Scale; GA = glatiramer acetate; IFN[beta]-1b = interferon beta 1b; FLAIR = fluid-attenuated inversion recovery; MS = multiple sclerosis; MSFC = Multiple Sclerosis Functional Composite; NEL = newly enhancing lesions; NL = new lesions; RRMS = relapsing-remitting MS; SNRS = Scripps Neurological Rating Scale.(C)2009AAN Enterprises, Inc.


Mlynash, M MD, MS; Olivot, J H. MD, PhD; Tong, D C. MD, FAHA; Lansberg, M G. et al
Yield of combined perfusion and diffusion MR imaging in hemispheric TIA
Neurology.
Status
Publish Ahead of Print, POST AUTHOR CORRECTIONS, 17 December 2008
Abstract
Objective: Transient ischemic attacks (TIA) predict future stroke. However, there are no sensitive and specific diagnostic criteria for TIA and interobserver agreement regarding the diagnosis is poor. Diffusion-weighted MRI (DWI) demonstrates acute ischemic lesions in approximately 30% of TIA patients; the yield of perfusion-weighted MRI (PWI) is unclear.Methods: We prospectively performed both DWI and PWI within 48 hours of symptom onset in consecutive patients admitted with suspected hemispheric TIAs of <24 hours symptom duration. Two independent raters, blinded to clinical features, assessed the presence and location of acute DWI and PWI lesions. Lesions were correlated with suspected clinical localization and baseline characteristics. Clinical features predictive of a PWI lesion were assessed.Results: Forty-three patients met the inclusion criteria. Thirty-three percent had a PWI lesion and 35% had a DWI lesion. Seven patients (16%) had both PWI and DWI lesions and 7 (16%) had only PWI lesions. The combined yield for identification of either a PWI or a DWI was 51%. DWI lesions occurred in the clinically suspected hemisphere in 93% of patients; PWI lesions in 86%. PWI lesions occurred more frequently when the MRI was performed within 12 hours of symptom resolution, in patients with symptoms of speech impairment, and among individuals younger than 60 years.Conclusions: The combination of early diffusion-weighted MRI and perfusion-weighted MRI can document the presence of a cerebral ischemic lesion in approximately half of all patients who present with a suspected hemispheric transient ischemic attack (TIA). MRI has the potential to improve the accuracy of TIA diagnosis.GLOSSARY: ACA = anterior cerebral artery; CI = confidence interval; DWI = diffusion-weighted MRI; ICA = internal carotid artery; MCA = middle cerebral artery; MRA = magnetic resonance angiography; MTT = mean transit time; OR = odds ratios; PCA = posterior cerebral artery; PWI = perfusion-weighted MRI; RR = risk ratios; TIA = transient ischemic attacks; TOAST = Trial of Org 10172 in Acute Stroke Treatment.(C)2009AAN Enterprises, Inc.

Articles from Stroke

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Henneman, Wouter J.P. MD; Sluimer, Jasper D. MD; Cordonnier, Charlotte et al
MRI Biomarkers of Vascular Damage and Atrophy Predicting Mortality in a Memory Clinic Population
Source
Stroke. 40(2):492-498, February 2009.
Abstract
Background and Purpose-: MRI biomarkers play an important role in the diagnostic work-up of dementia, but their prognostic value is less well-understood. We investigated if simple MRI rating scales predict mortality in a memory clinic population.Methods-: We included 1138 consecutive patients attending our memory clinic. Diagnostic categories were: subjective complaints (n=220), mild cognitive impairment (n=160), Alzheimer disease (n=357), vascular dementia (n=46), other dementia (n=136), and other diagnosis (n=219). Baseline MRIs were assessed using visual rating scales for medial temporal lobe atrophy (range, 0-4), global cortical atrophy (range, 0-3), and white matter hyperintensities (range, 0-3). Number of microbleeds and presence of infarcts were recorded. Cox-regression models were used to calculate the risk of mortality.Results-: Mean follow-up duration was 2.6 (+/-1.9) years. In unadjusted models, all MRI markers except infarcts predicted mortality. After adjustment for age, sex, and diagnosis, white matter hyperintensities, and microbleeds predicted mortality (white matter hyperintensities: hazard ratio [HR], 1.2; 95% CI, 1.0-1.4; microbleeds: HR, 1.02 95% CI, 1.00-1.03; categorized: HR, 1.5; 95% CI, 1.1-2.0). The predictive effect of global cortical atrophy was restricted to younger subjects (HR, 1.7; 95% CI, 1.2-2.6). An interaction between microbleeds and global cortical atrophy indicated that mortality was especially high in patients with both microbleeds and global cortical atrophy.Conclusion-: Simple MRI biomarkers, in addition to their diagnostic use, have a prognostic value with respect to mortality in a memory clinic population. Microbleeds were the strongest predictor of mortality.(C) 2009 American Heart Association, Inc.

Burns, Joseph D. MD; Huston, John III MD; Layton, Kennith F. et al
Intracranial Aneurysm Enlargement on Serial Magnetic Resonance Angiography: Frequency and Risk Factors.
Stroke. 40(2):406-411, February 2009.
Abstract
Background and Purpose-: Size of an unruptured intracranial aneurysm (UIA) may be an important risk factor for rupture. Accordingly, serial noninvasive imaging is commonly used to assess untreated UIA for enlargement. Few data exist regarding the frequency and predictors of enlargement. We obtained this information from a group of patients followed with serial MR angiography (MRA).Methods-: We retrospectively identified 165 patients with 191 UIA followed with serial MRA. Fusiform aneurysms, UIA <2>=13 mm, respectively (P<0.001>=8 mm in diameter were at highest risk for enlargement (OR, 7.25; 95% CI, 1.96 to 27.1). There was a trend toward increased risk of enlargement in patients with multiple aneurysms (OR, 2.50; 95% CI, 0.86 to 7.53).Conclusions-: Over a median follow-up period of 47 months, 10% of UIA enlarged. Larger aneurysms had a significantly increased risk of enlargement. The likelihood of enlargement was highest in aneurysms with diameters >=8 mm. However, a clinically significant proportion of small aneurysms grow, and this growth can be detected by serial MRA.

Interventional Cardiovascular Magnetic Resonance

Interventional Cardiovascular Magnetic Resonance: Still Tantalizing
Ratnayaka K, Faranesh AZ, Guttman MA, Kocaturk O, Saikus CE, Lederman RJ
Journal of Cardiovascular Magnetic Resonance 2008, 10:62 (29 December 2008)
[Abstract] [Provisional PDF]

Articles from Stroke

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Toth, Gabor ; Albers, Gregory W.
Use of MRI to Estimate the Therapeutic Window in Acute Stroke: Is Perfusion-Weighted Imaging/Diffusion-Weighted Imaging Mismatch an EPITHET for Salvageable Ischemic Brain Tissue?
Source
Stroke. 40(1):333-335, January 2009.

Cai, Weibo ; Guzman, Raphael ; Hsu, Andrew R. ; Wang, Hui ; Chen, Kai et al
Positron Emission Tomography Imaging of Poststroke Angiogenesis
Stroke. 40(1):270-277, January 2009.
Abstract
Background and Purpose-: Vascular endothelial growth factor (VEGF) and VEGF receptors (VEGFRs) play important roles during neurovascular repair after stroke. In this study, we imaged VEGFR expression with positron emission tomography (PET) to noninvasively analyze poststroke angiogenesis.Methods-: Female Sprague-Dawley rats after distal middle cerebral artery occlusion surgery were subjected to weekly MRI, 18F-FDG PET, and 64Cu-DOTA-VEGF121 PET scans. Several control experiments were performed to confirm the VEGFR specificity of 64Cu-DOTA-VEGF121 uptake in the stroke border zone. VEGFR, BrdU, lectin staining, and 125I-VEGF165 autoradiography on stroke brain tissue slices were performed to validate the in vivo findings.Results-: T2-weighed MRI correlated with the "cold spot" on 18F-FDG PET for rats undergoing distal middle cerebral artery occlusion surgery. The 64Cu-DOTA-VEGF121 uptake in the stroke border zone peaked at [almost equal to]10 days after surgery, indicating neovascularization as confirmed by histology (VEGFR-2, BrdU, and lectin staining). VEGFR specificity of 64Cu-DOTA-VEGF121 uptake was confirmed by significantly lower uptake of 64Cu-DOTA-VEGFmutant in vivo and intense 125I-VEGF165 uptake ex vivo in the stroke border zone. No appreciable uptake of 64Cu-DOTA-VEGF121 was observed in the brain of sham-operated rats.Conclusions-: For the first time to our knowledge, we successfully evaluated the VEGFR expression kinetics noninvasively in a rat stroke model. In vivo imaging of VEGFR expression could become a significant clinical tool to plan and monitor therapies aimed at improving poststroke angiogenesis.

Izquierdo-Garcia, David ; Davies, John R. ; Graves, Martin J. et al
Comparison of Methods for Magnetic Resonance-Guided [18-F]Fluorodeoxyglucose Positron Emission Tomography in Human Carotid Arteries: Reproducibility, Partial Volume Correction, and Correlation Between Methods.
Stroke. 40(1):86-93, January 2009.
Abstract
Background and Purpose-: Inflammation is a major risk factor for atherosclerotic plaque rupture and clinical events. Previous studies have shown that plaque [18F]fluorodeoxyglucose (FDG) uptake correlates with macrophage content. In this study we examined the reproducibility of 3 methods of quantifying plaque FDG uptake in the carotid arteries using positron emission tomography (PET). The correlation between 2 simplified uptake parameters (standardized uptake value [SUV], vessel wall-to-blood ratio [VBR]) and a gold standard technique (influx rate [Ki]) was also determined. We used MRI to correct carotid plaque FDG uptake for partial volume error.Methods-: Seven patients with a recent carotid territory transient ischemic attack underwent imaging twice within 8 days using MR and FDG-PET. MR coregistered to PET was used to delineate regions of interest, and to facilitate partial volume correction (PVC).Results-: SUV was the most reproducible parameter irrespective of whether it was normalized by body surface area (BSA), lean body mass, or weight (intraclass correlation coefficient=0.85, 0.88, and 0.90, respectively). VBR correlated better to Ki than SUV (r=0.58 VBR, r=0.46 SUVBSA). PVC improved these correlations to r=0.81 VBR and r=0.76 SUVBSA, and only slightly degraded the reproducibility of SUV (intraclass correlation coefficient=0.83-0.85).Conclusions-: MR-guided FDG-PET is a highly reproducible technique in the carotid artery and the excellent anatomic detail provided by MR facilitates PVC. Of the methods examined, SUVBSAPVC appears to represent the best compromise between reproducible and accurate determination of FDG metabolism in carotid artery vessel wall.

Articles from Anesthesia and Analgesia

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Dzwonczyk, Roger; Fujii, Jeffrey T. ; Simonetti, Orlando ; Nieves-Ramos, Ricardo ; Bergese, Sergio D.
Electrical Noise in the Intraoperative Magnetic Resonance Imaging Setting
Anesthesia & Analgesia. 108(1):181-186, January 2009.
Abstract
BACKGROUND: Intraoperative magnetic resonance imaging (iMRI) is a tool now commonly used in neurosurgery. Safe and reliable patient care in this (or any other) operating room setting depends on an environment, where electrical noise (EN) does not interfere with the operation of the electronic monitoring or imaging equipment. In this investigation, we evaluated the EN generated by the iMRI system and the anesthesia patient monitor used at this institution that impacts the performance of these two devices.METHODS: We measured the EN generated by our iMRI-compatible anesthesia patient monitor as detected by the EN analysis algorithm in our iMRI system. We measured the EN generated by our iMRI system during scanning as detected in the electrocardiogram (ECG) waveform of our patient monitor. We analyzed the effects on EN reduction and signal quality of the ECG noise filters provided in our iMRI-compatible anesthesia patient monitor.RESULTS: Our patient monitor generated EN that was detectable by the iMRI EN analysis algorithm; however, this interference was within the iMRI manufacturer's acceptable limits for an iMRI scan (<10%>

Skubas, Nikolaos

Intraoperative Doppler Tissue Imaging Is a Valuable Addition to Cardiac Anesthesiologists' Armamentarium: A Core Review. [Review]
Anesthesia & Analgesia. 108(1):48-66, January 2009.
Abstract
Endocardial motion and surface/volume changes during the cardiac cycle are echocardiographic methods for regional (analysis of wall motion) and global (fractional area change, stroke volume, and ejection fraction) evaluation of cardiac function. These conventional methods can be subjective, and/or time consuming and, depending upon circumstances, may divert the anesthesiologist's attention from intraoperative activities. Doppler tissue imaging (DTI) is a novel echocardiographic technique, which displays and measures systolic and diastolic velocity from a myocardial region. DTI is simple to perform and independent of adequate endocardial imaging. The numeric information (velocity or time intervals) is easily obtained and measured. Assessment of systolic and diastolic function on regional (detection of ischemia) as well as global level (ejection fraction, grading of diastolic dysfunction) and evaluation of filling pressure can be derived from DTI signals and used by any practicing cardiac anesthesiologist. This review describes the principles, imaging modalities, and clinical applications of DTI.(C) 2009 by International Anesthesia Research Society.

Tousignant, Claude
CON: Intraoperative Doppler Tissue Imaging Is a Valuable Addition to Cardiac Anesthesiologists' Armamentarium. [Editorial]
Source
Anesthesia & Analgesia. 108(1):41-47, January 2009.

Kronzon, Itzhak MD

PRO: Intraoperative Doppler Tissue Imaging Is a Valuable Addition to Cardiac Anesthesiologists' Armamentarium. [Editorial]
Source
Anesthesia & Analgesia. 108(1):37-40, January 2009.

Hilberath, Jan N. ; Shernan, Stanton K. ; Segal, Scott ; Smith, Brian et al

The Feasibility of Epicardial Echocardiography for Measuring Aortic Valve Area by the Continuity Equation

Anesthesia & Analgesia. 108(1):17-22, January 2009.
Abstract
BACKGROUND: Measuring the aortic valve area (AVA) remains an important component of a comprehensive intraoperative echocardiographic examination in patients undergoing aortic valve surgery. Epicardial echocardiography (EE) represents an accessible alternative to transesophageal echocardiography (TEE), however, its agreement and correlation with other imaging modalities for measuring AVA has not been systematically validated.METHODS: EE was used in 85 patients undergoing cardiac surgery to measure AVA (AVA-EE) using the continuity equation. AVA-EE was compared to measurements obtained by intraoperative transesophageal echocardiography (AVA-TEE) in the same population. In a subset of patients, AVA-EE was also compared to AVA measurements from either preoperative transthoracic echocardiography (AVA-TTE) (n = 65) or cardiac catheterization (AVA-Cath) (n = 35) that were acquired within 4 wk before the date of surgery.RESULTS: Adequate trans-AV Doppler recordings were obtained in 94% of patients for AVA-TEE and 100% of patients for AVA-EE. EE measurements of AVA showed close agreement with TEE measurements (mean difference [bias] +/- 95% CI = -0.09 cm2 +/- 0.18 cm2, r2 = 0.83, P < ci =" -0.03" r2 =" 0.87," ci =" -0.06" r2 =" 0.81,">

Maintenance of Anesthesia in Children Undergoing Magnetic Resonance Imaging

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Heard, Christopher ; Burrows, Frederick ; Johnson, Kristin ; Joshi, Prashant et al
A Comparison of Dexmedetomidine-Midazolam with Propofol for Maintenance of Anesthesia in Children Undergoing Magnetic Resonance Imaging
Anesthesia & Analgesia. 107(6):1832-1839, December 2008.
Abstract
BACKGROUND: Dexmedetomidine is an [alpha]2 agonist that is currently being investigated for its suitability to provide anesthesia for children. We compared the pharmacodynamic responses to dexmedetomidine-midazolam and propofol in children anesthetized with sevoflurane undergoing magnetic resonance imaging (MRI).
METHODS: Forty ASA 1 or 2 children, 1-10 yr of age, were randomized to receive either dexmedetomidine-midazolam or propofol for maintenance of anesthesia for MRI after a sevoflurane induction. Dexmedetomidine was administered as an initial loading dose (1 [mu]g/kg) followed by a continuous infusion (0.5 [mu]g [middle dot] kg-1 [middle dot] h-1). Midazolam (0.1 mg/kg) was administered IV when the infusion commenced. Propofol was administered as a continuous infusion (250-300 [mu]g [middle dot] kg-1 [middle dot] min-1). Recovery times and hemodynamic responses were recorded by one nurse who was blinded to the treatments.
RESULTS: We found that the times to fully recover and to discharge from the ambulatory unit after dexmedetomidine administration were significantly greater (by 15 min) than those after propofol. Analysis of variance demonstrated that heart rate was slower and systolic blood pressure was greater with dexmedetomidine than propofol. Respiratory indices for the two treatments were similar. During recovery, hemodynamic responses were similar. Cardiorespiratory indices during anesthesia and recovery remained within normal limits for the children's ages. No adverse events were recorded.
CONCLUSION: Dexmedetomidine-midazolam provides adequate anesthesia for MRI although recovery is prolonged when compared with propofol. Heart rate was slower and systolic blood pressure was greater with dexmedetomidine when compared with propofol. Respiratory indices were similar for the two treatments.

MRSA in MRI suites

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Dear AuntMinnie Member,
In addition to radiation dose, contrast reactions, and other imaging-related perils, you can add methicillin-resistant Staphylococcus aureus (MRSA) to the list. While MRSA hasn't yet grabbed headlines, lax infection control practices in many MRI suites could make it a growing problem.
That's according to an article by Dr. Peter A. Rothschild that we're featuring this week in our MRI Digital Community. In the article, Dr. Rothschild explains how many MRI facilities fail to take even the most basic precautions to avoid MRSA contamination.
Some facilities don't wipe down equipment after use, while others don't replace padding that's become worn or ripped -- creating environments ripe for MRSA colonization. It particularly is a problem given that some 1% of the U.S. population is colonized with MRSA, and even asymptomatic patients can spread the bacteria.
Fortunately, Dr. Rothschild offers an 11-step program that MRI facilities can implement to reduce the risk of MRSA contamination. Find out how by clicking here, or visit our MRI Digital Community at mri.auntminnie.com.

Articles from Spine journal November 2008

Link to journal
Niemelainen, Riikka ; Battie, Michele C. ; Gill, Kevin ; Videman, Tapio
The Prevalence and Characteristics of Thoracic Magnetic Resonance Imaging Findings in Men
Spine. 33(23):2552-2559, November 1, 2008.
Abstract
Study Design. A cross-sectional study of thoracic magnetic resonance image (MRI) findings.Objective. To examine the prevalence of different thoracic MRI findings for T6-T12 and their associations with age and one another by level.Summary of Background Data. There is a dearth of descriptive epidemiology of thoracic MRI findings in the general population.Methods. Thoracic MRIs of 524 men were assessed qualitatively and quantitatively for a variety of findings, including disc bulging, height and signal, vertebral deformities, endplate irregularities, osteophytes, and hemangiomas. Descriptive statistics, correlation coefficients and STATA's survey analysis were used.Results. In the lower thoracic spine, 5.4% to 9.5% of the discs, depending on level, were qualitatively assessed as moderately to severely narrowed. Anterior bulging was more common than posterior, which was relatively rare and mild when present. Signal was lower in the midthoracic than lower discs. At least 1 moderate or severe vertebral deformity was found in 6.1% of the subjects, suggesting fracture, and hemangiomas were identified in 2.3% of subjects. Disc signal correlated most highly with age (r = 0.31-0.42). Qualitatively assessed disc height narrowing (r = 0.29-0.46) and quantitative disc height (r = 0.11-0.29) were associated with disc signal. Upper and lower endplate irregularities were associated with one another (r = 0.17-0.32), as were bulging and osteophytes, anteriorly (r = 0.35-0.61) and posteriorly (r = 0.26-0.45).Conclusion. Degenerative MRI findings beyond a mild grade were not commonly observed in the thoracic spine among 35-70-year-old men. Posterior bulges, in particular, were rare. The highest correlation with age existed for disc signal. Different MRI findings were associated with one another, but the magnitude of association varied by level. The effects of individual judgments and disc level on prevalence rates were apparent.(C) 2008 Lippincott Williams & Wilkins, Inc.

Matsunaga, Shunji ; Nakamura, Kozo ; Seichi, Atsushi ; Yokoyama, Toru ; Toh, Satoshi et al
Radiographic Predictors for the Development of Myelopathy in Patients With Ossification of the Posterior Longitudinal Ligament: A Multicenter Cohort Study
Spine. 33(24):2648-2650, November 15, 2008.
Abstract
Study Design. A multicenter cohort study was performed retrospectively.Objective. To identify radiographic predictors for the development of myelopathy in patients with ossification of the posterior longitudinal ligaments (OPLL).Summary of Background Data. The pathomechanism of myelopathy in the OPLL remains unknown. Some patients with large OPLL have not exhibited myelopathy for a long periods of time. Predicting the course of future neurologic deterioration in asyptomatic patients with OPLL is difficult at their initial visit.Methods. A total of 156 OPLL patients from 16 spine institutes with an average of 10.3 years of follow-up were reviewed. Subjects underwent a plain roentgenogram, computed tomography (CT), and magnetic resonance imaging of the cervical spine during the follow-up. The trauma history of the cervical spine, maximum percentage of spinal canal stenosis in a plain roentgenogram and CT, range of motion of the cervical spine, and axial ossified pattern in magnetic resonance imaging or CT were reviewed in relation to the existence of myelopathy.Results. All 39 patients with greater than 60% spinal canal stenosis on the plain roentgenogram exhibited myelopathy. Of 117 patients with less than 60% spinal canal stenosis, 57 (49%) patients exhibited myelopathy. The range of motion of the cervical spine was significantly larger in patients with myelopathy than in those of without it. The axial ossified pattern could be classified into 2 types: a central type and a lateral deviated type. The incidence of myelopathy in patients with less than 60% spinal canal stenosis was significantly higher in the lateral deviated-type group than in the central-type group. Fifteen patients of 156 subjects developed trauma-induced myelopathy. Of the 15 patients, 13 had mixed-type OPLL and 2 had segmental-type OPLL.Conclusion. Static and dynamic factors were related to the development of myelopathy in OPLL.