Movement artifacts compromise image quality and may interfere with interpretation, especially in magnetic resonance imaging (MRI) applications with low signal-to-noise ratio such as functional MRI or ...diffusion tensor imaging, and when imaging small lesions. High image resolution has high sensitivity to motion artifacts and often prolongs scan time that again aggravates movement artifacts. During the scan fast imaging techniques and sequences, optimal receiver coils, careful patient positioning, and instruction may minimize movement artifacts. Physiological noise sources are motion from respiration, flow and pulse coupled to cardiac cycles, from the swallowing reflex and small spontaneous head movements. Par example, in resting-state functional MRI spontaneous neuronal activity adds 1-2% of signal change, even under optimal conditions signal contributions from physiological noise remain a considerable fraction hereof. Movement tracking during imaging may allow for prospective correction or postprocessing steps separating signal and noise.
Data remain limited on sex-differences in patients with oral anticoagulant (OAC)-related intracerebral hemorrhage (ICH). We aim to explore similarities and differences in risk factors, acute ...presentation, treatments, and outcome in men and women admitted with OAC-related ICH.
This study was a retrospective observational study based on 401 consecutive patients with OAC-related ICH admitted within 24 h of symptom onset. The study was registered on osf.io. We performed logarithmic regression and cox-regression adjusting for age, hematoma volume, Charlson Comorbidity Index (CCI), and pre-stroke modified Ranking Scale (mRS). Gender and age were excluded from CHA
DS
-VASc and CCI was not adjusted for age.
A total of 226 men and 175 women were identified. More men were pre-treated with vitamin K-antagonists (73.5% men
. 60.6% women) and more women with non-vitamin K-antagonist oral anticoagulants (26.5% men
. 39.4% women),
= 0.009. Women were older (mean age 81.9
. 76.9 years,
< 0.001). CHA
DS
-VASc and CCI were similar in men and women.Hematoma volumes (22.1 ml in men and 19.1 ml in women) and National Institute of Health Stroke Scale (NIHSS) scores (13
. 13) were not statistically different, while median Glasgow Coma Scale (GCS) was lower in women, (14 8;15
. 14 10;15
= 0.003).Women's probability of receiving reversal agents was significantly lower (adjusted odds ratio
= 0.52,
= 0.007) but not for surgical clot removal (
= 0.56,
= 0.25). Women had higher odds of receiving do-not-resuscitate (DNR) orders within a week (
= 1.67,
= 0.04). There were no sex-differences in neurological deterioration (
= 1.48,
= 0.10), ability to walk at 3 months (
= 0.69,
= 0.21) or 1-year mortality (adjusted hazard ratio = 1.18,
= 0.27).
Significant sex-differences were observed in age, risk factors, access to treatment, and DNRs while no significant differences were observed in comorbidity burden, stroke severity, or hematoma volume. Outcomes, such as adjusted mortality, ability to walk, and neurological deterioration, were comparable. This study supports the presence of sex-differences in risk factors and care but not in presentation and outcomes.
Central sensitization plays a pivotal role in maintenance of pain and is believed to be intricately involved in several chronic pain conditions. One clinical manifestation of central sensitization is ...secondary hyperalgesia. The degree of secondary hyperalgesia presumably reflects individual levels of central sensitization. The objective of this study was to investigate the association between areas of secondary hyperalgesia and volumes of the caudate nuclei and other brain structures involved in pain processing.
We recruited 121 healthy male participants; 118 were included in the final analysis. All participants underwent whole brain magnetic resonance imaging (MRI). Prior to MRI, all participants underwent pain testing. Secondary hyperalgesia was induced by brief thermal sensitization. Additionally, we recorded heat pain detection thresholds (HPDT), pain during one minute thermal stimulation (p-TS) and results of the Pain Catastrophizing Scale (PCS) and Hospital Anxiety and Depression score (HADS).
We found no significant associations between the size of the area of secondary hyperalgesia and the volume of the caudate nuclei or of the following structures: primary somatosensory cortex, anterior and mid cingulate cortex, putamen, nucleus accumbens, globus pallidus, insula and the cerebellum. Likewise, we found no significant associations between the volume of the caudate nuclei and HPDTs, p-TS, PCS and HADS.
Our findings indicate that the size of the secondary hyperalgesia area is not associated with the volume of brain structures relevant for pain processing, suggesting that the propensity to develop central sensitization, assessed as secondary hyperalgesia, is not correlated to brain structure volume.
Background Is computed tomography (CT)–verified leukoaraiosis (LA) a risk factor for post-thrombolytic hemorrhagic transformation and symptomatic hemorrhage? Methods (1) Retrospective analysis based ...on a prospectively planned single-center registry of consecutive tissue plasminogen activator (tPA)–treated patients within 4.5 hours from symptom onset. Standard work-up included baseline noncontrast CT and CT angiography and next day follow-up noncontrast CT. Baseline noncontrast CT LA was graded using Fazekas' score and dichotomized as the absence (Fazekas, 0) or the presence (Fazekas, 1-3). Hemorrhagic transformation was rated using European Cooperative Acute Stroke Study (ECASS) criteria. Symptomatic intracerebral hemorrhage was defined as hemorrhage and deterioration of National Institutes of Health Stroke Scale (NIHSS) of 4 or greater within 36 hours from symptom onset. Endovascularly treated patients were excluded. (2) Pooled analysis with 1312 tPA-treated patients from literature. Results In all, 311 tPA-treated patients were included between April 2009 and July 2012. LA was present in 113 (36%). Twenty-three (7%) showed hemorrhagic transformation. LA positive patients had significantly higher hemorrhagic transformation frequency (11.5%, P = .04). LA doubled hemorrhagic transformation risk (odds ratio OR, 2.4; 95% confidence interval CI, 1.4-5.8). Only 4 patients developed symptomatic intracerebral hemorrhage, 3 with LA. LA was not an independent risk factor for hemorrhagic transformation ( P = .2). Pooled analysis of 1623 patients in total, hereof 479 LA positive patients, showed significantly higher symptomatic intracerebral hemorrhage frequency in 35 (7.3%) LA positive than that in 44 (3.8%) LA negative patients, ( P = .005) and doubled symptomatic intracerebral hemorrhage risk in LA positives (OR, 1.97; 95% CI 1.22-3.19). Conclusions LA doubles the risk of post-thrombolytic hemorrhagic transformation and symptomatic hemorrhage; this finding does not support withholding thrombolysis from patients with LA.
Lumbar punctures are performed in different medical settings and are a key procedure in the diagnosis of several neurological conditions. Complications are rare and generally self-limiting. There are ...no reports of symptomatic accumulation of fluid in the epidural space after lumbar puncture in adults and there are no studies on long-term outcome after post dural puncture headache (PDPH).
A lumbar puncture was performed in a 29 y.o. slender woman with unspecific symptoms to rule out neuro-infection. Next day MRI showed substantial accumulation of CSF in the epidural space from C2 to the sacrum dislocating the spinal chord in the spinal canal. The condition was ameliorated by epidural blood-patching. At 5 months she was still impaired by severe orthostatic headache.
The only plausible explanation for the massive CSF leak was a dural tear occurring during multiple attempts of lumbar puncture. Anterior dislocation of the spinal chord due to CSF leak is not a recognised complication to lumbar puncture. This complication was followed by long-term disability in our case. The diagnosis can be made by MRI. A difficult procedure with several attempts and use of traumatic technique may increase risk of this complication.
Objectives We investigated the prevalence and long-term risk associated with intracranial atherosclerosis identified during routine evaluation. Design This study presents data from a prospective ...cohort of patients admitted to our stroke unit for thrombolysis evaluation. Setting and participants We included 652 with a final diagnosis of ischaemic stroke or transient ischaemic attack (TIA) from April 2009 to December 2011. All patients were acutely evaluated with cerebral CT and CT angiography (CTA). Acute radiological examinations were screened for intracranial arterial stenosis (IAS) or intracranial arterial calcifications (IAC). Intracranial stenosis was grouped into 30–50%, 50–70% and >70% lumen reduction. The extent of IAC was graded as number of vessels affected. Primary and secondary outcome measure Patients were followed until July 2013. Recurrence of an ischaemic event (stroke, ischaemic heart disease (IHD) and TIA) was documented through the national chart system. Poor outcome was defined as death or recurrence of ischaemic event. Results 101 (15.5%) patients showed IAS (70: 30–50%, 29: 50–70% and 16: >70%). Two-hundred and fifteen (33%) patients had no IAC, 339 (52%) in 1–2 vessels and 102 (16%) in >2 vessels. During follow-up, 53 strokes, 20 TIA and 14 IHD occurred, and 95 patients died. The risk of poor outcome was significantly different among different extents of IAS as well as IAC (log-rank test p<0.01 for both). In unadjusted analysis IAS and IAC predicted poor outcome and recurrent ischaemic event. When adjusted, IAS and IAC independently increased the risk of a recurrent ischaemic event (IAS: HR 1.67; CI 1.04 to 2.64 and IAC: HR 1.22; CI 1.02 to 1.47). Conclusions Intracranial atherosclerosis detected during acute evaluation predicts an increased risk of recurrent stroke.
In a prospective cohort of patients with transient ischemic attack (TIA), we investigated usefulness and feasibility of arterial spin labeling (ASL) perfusion and susceptibility weighted imaging ...(SWI) alone and in combination with standard diffusion weighted (DWI) imaging in subacute diagnostic work-up. We investigated rates of ASL and SWI changes and their potential correlation to lasting infarction 8 weeks after ictus.
Patients with TIA underwent 3T-MRI including DWI, ASL and SWI within 72 h of symptom onset. We defined lasting infarction as presence of 8-week MRI T2-fluid attenuated inversion recovery (FLAIR) hyperintensity or atrophy in the area of initial DWI-lesion.
We included 116 patients. Diffusion and perfusion together identified more patients with ischemia than either alone (59% vs. 40%, p < 0.0001). The presence of both diffusion and perfusion lesions had the highest rate of 8-week gliosis scars, 65% (p < 0.0001). In white matter, DWI-restriction was the determinant factor for scar development. However, in cortical gray matter half of lesions with perfusion deficit left a scar, while lesions without perfusion change rarely resulted in scars (56% versus 21%, p = 0.03). SWI lesions were rare (6%) and a subset of perfusion lesions. SWI-lesions with DWI-lesions were all located in cortical gray matter and showed high scar rate.
ASL perfusion increased ischemia detection in patients with TIA, and was most useful in conjunction with DWI. ASL was fast, robust and useful in a subacute clinical diagnostic setting. SWI had few positive findings and did not add information.
http://www.clinicaltrials.gov . Unique Identifier NCT01531946 , prospectively registered February 9, 2012.
Diffusion tensor imaging may aid brain ischemia assessment but is more time consuming than conventional diffusion-weighted imaging (DWI). We compared 3-gradient direction DWI (3DWI) and 20-gradient ...direction DWI (20DWI) standard vendor protocols in a hospital-based prospective cohort of patients with transient ischemic attack (TIA) for lesion detection, lesion brightness, predictability of persisting infarction, and final infarct size.
We performed 3T-magnetic resonance imaging including diffusion and T2-fluid attenuated inversion recovery (FLAIR) within 72 h and 8 weeks after ictus. Qualitative lesion brightness was assessed by visual inspection. We measured lesion area and brightness with manual regions of interest and compared with homologous normal tissue.
117 patients with clinical TIA showed 78 DWI lesions. 2 lesions showed only on 3DWI. No lesions were uniquely 20DWI positive. 3DWI was visually brightest for 34 lesions. 12 lesions were brightest on 20DWI. The median 3DWI lesion area was larger for lesions equally bright, or brightest on 20DWI median (IQR) 39 (18-95) versus 18 (10-34) mm
,
= 0.007. 3DWI showed highest measured relative lesion signal intensity median (IQR) 0.77 (0.48-1.17) versus 0.58 (0.34-0.81),
= 0.0006. 3DWI relative lesion signal intensity was not correlated to absolute signal intensity, but 20DWI performed less well for low-contrast lesions. 3DWI lesion size was an independent predictor of persistent infarction. 3-gradient direction apparent diffusion coefficient areas were closest to 8-week FLAIR infarct size.
3DWI detected more lesions and had higher relative lesion SI than 20DWI. 20DWI appeared blurred and did not add information.
http://www.clinicaltrials.gov. Unique Identifier NCT01531946.
Background Incidental findings of suspect lung opacities are common in computed tomography (CT)–based thorax examinations, especially in high-risk patients, such as stroke patients. Screening with CT ...of the thorax has detected lung cancer in approximately .31%-1.20% of high-risk populations. The aim of the present study was to report the frequency of suspect lung opacities on routine acute stroke imaging. Methods Seven hundred and fifty-seven consecutive stroke patients evaluated for intravenous thrombolysis treatment within 4.5 hours of symptom debut, from June 2009 to December 2011, were included in a prospective registry on which this analysis was based. On admission, CT angiography from the aortic arch to vertex was performed, including the lung apices, corresponding to 1/3 of the total lung volume. A senior neuroradiologist reviewed all scans registering suspect lung opacities, which subsequently were characterized as either malignant, presumed malignant, presumed benign or benign, based on radiologic parameters of malignancy, positron emission tomography scan, histology, and clinical features. Results Suspect lung opacities appeared on the CT angiography in 20 patients (2.6%). Five suspect lung opacities were categorized as malignant and 3 suspect lung opacities were categorized as presumed malignant. This corresponds to an incidence of 1.1% (8 of 750). Conclusions Malignant lung opacities were found in approximately 1% of this high-risk population, whereas our findings do not support full CT of the thorax as routine on stroke patients.
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