Angiographic features, collaterals, and infarct topography of symptomatic occlusive radiation vasculopathy: a case-referent study.

BACKGROUND AND PURPOSE: Occlusive radiation vasculopathy (ORV) predisposes head-and-neck cancer survivors to ischemic strokes. METHODS: We analyzed the digital subtraction angiography acquired in 96 patients who had first-ever transient ischemic attack or ischemic strokes attributed to ORV. Another age-matched 115 patients who had no radiotherapy but symptomatic high-grade (>70%) carotid stenoses were enrolled as referent subjects. Digital subtraction angiography was performed within 2 months from stroke onset and delineated carotid and vertebrobasilar circulations from aortic arch up to intracranial branches. Two reviewers blinded to group assignment recorded all vascular lesions, collateral status, and infarct pattern. RESULTS: ORV patients had less atherosclerotic risk factors at presentation. In referent patients, high-grade stenoses were mostly focal at the proximal internal carotid artery. In contrast, high-grade ORV lesions diffusely involved the common carotid artery and internal carotid artery and were more frequently bilateral (54% versus 22%), tandem (23% versus 10%), associated with complete occlusion in one or both carotid arteries (30% versus 9%), vertebral artery (VA) steno-occlusions (28% versus 16%), and external carotid artery stenosis (19% versus 5%) (all P<0.05). With comparable rates of vascular anomaly, ORV patients showed more established collateral circulations through leptomeningeal arteries, anterior communicating artery, posterior communicating artery, suboccipital/costocervical artery, and retrograde flow in ophthalmic artery. In terms of infarct topography, the frequencies of cortical or subcortical watershed infarcts were similar in both groups. CONCLUSIONS: ORV angiographic features and corresponding collaterals are distinct from atherosclerotic patterns at initial stroke presentation. Clinical decompensation, despite more extensive collateralization, may precipitate stroke in ORV.

MRI of cardiac iron overload.

Transfusion therapy has greatly improved the survival of transfusion dependent thalassemia major (TM) patients; however, the resultant iron load damages tissues including the heart, liver and endocrine organs. Among these, heart complication still remains the leading cause of mortality. Myocardial iron deposition can occur independently of other solid organ involvement; conversely, the heart may be spared despite heavy siderosis in other tissues. Iron chelation treatment diminishes the risk of hemosiderosis; however, the chelation treatment has its own toxicities and might not be available to all patients due to costs. Close monitoring of individual organ iron concentration and function is thus important for optimization of individual patient care. This review outlines the importance and clinical significance of recently available MRI techniques for monitoring cardiac iron load.

Frequency and predictors of proxy-confirmed post-stroke cognitive complaints in lacunar stroke patients without major depression.

OBJECTIVE: Many lacunar stroke patients complained of cognitive decline after stroke. This study aims to investigate the factors underlying post-stroke cognitive complaints in these patients. METHODS: Seventy-five consecutive lacunar stroke patients without major depression were recruited for the study. Stroke severity was measured using NIHSS score and MRI was performed during the acute admission period. At 3 months, objective psychometric performance and depressive symptoms were assessed. Post-stroke cognitive complaints were corroborated by a proxy. Using logistic regression we examined the contribution of demographic features, stroke severity, objective psychometric scores, depressive symptoms, and imaging features (white matter lesion volume and infarct measures) to post-stroke cognitive complaints. RESULTS: Thirty-two (42.7%) patients had post-stroke cognitive complaints. Patients with post-stroke cognitive complaints had more depressive symptoms and worse psychometric performance than those without. In the multivariate logistic regression model, only the severity of depressive symptoms was independently associated with post-stroke cognitive complaints. CONCLUSIONS: This study suggests that post-stroke cognitive complaints are frequent among lacunar stroke patients without major depression and are prominently determined by the subclinical depressive symptomatology.

International reproducibility of single breathhold T2* MR for cardiac and liver iron assessment among five thalassemia centers.

PURPOSE: To examine the reproducibility of the single breathhold T2* technique from different scanners, after installation of standard methodology in five international centers. MATERIALS AND METHODS: Up to 10 patients from each center were scanned twice locally for local interstudy reproducibility of heart and liver T2*, and then flown to a central MR facility to be rescanned on a reference scanner for intercenter reproducibility. Interobserver reproducibility for all scans was also assessed. RESULTS: Of the 49 patients scanned, the intercenter reproducibility for T2* was 5.9% for the heart and 5.8% for the liver. Local interstudy reproducibility for T2* was 7.4% for the heart and 4.6% for the liver. Interobserver reproducibility for T2* was 5.4% for the heart and 4.4% for the liver. CONCLUSION: These data indicate that T2* MR may be developed into a widespread test for tissue siderosis providing that well-defined and approved imaging and analysis techniques are used.

Papillary lesions of the breast--accuracy of core biopsy.

AIMS: To assess the accuracy of diagnosing papillary breast lesions in core needle biopsy. METHODS AND RESULTS: One hundred biopsy specimens of papillary breast lesions were reviewed and compared with the final excisional diagnoses. The discordant biopsy specimens were stained for oestrogen receptor (ER), cytokeratin (CK) 14 and p63, and these specimens were reclassified based on these results. The overall core biopsy accuracy, false-positive and false-negative rate were 79%, 5% and 16%, respectively. A benign core biopsy specimen diagnosis gave a false-negative rate of 10%, and malignant core biopsy specimen diagnosis did not give any false-positive results. Using homogeneous ER (epithelial), positive CK14 (epithelial) and p63 (myoepithelial) immunoreactivity as benign criteria, the discordant rate was reduced by 30% and 69% when using all three or two of these three criteria for diagnosis. However, false-positive and -negative cases could not be totally eliminated. CONCLUSIONS: Immunohistochemistry is helpful in core biopsy diagnosis of papillary breast lesions, but some cases remained misdiagnosed.

The validity, reliability and clinical utility of the Hong Kong Montreal Cognitive Assessment (HK-MoCA) in patients with cerebral small vessel disease.

BACKGROUND/AIMS: To evaluate the psychometric properties of the Hong Kong Montreal Cognitive Assessment (HK-MoCA) in patients with cerebral small vessel disease (SVD). METHODS: 40 SVD patients and 40 matched controls were recruited. Concurrent and criterion validity, inter-rater and test-retest reliability, internal consistency of the HK-MoCA were examined and clinical observations were made. RESULTS: Performance on the HK-MoCA was significantly predicted by both executive (beta = 0.23, p = 0.013) and non-executive (beta = 0.64, p < 0.001) composite scores. It differentiated SVD patients from controls (area under the curve = 0.81, p < 0.001) with an optimal cutoff at 21/22. Reliability, internal consistency and clinical utility were good. CONCLUSION: The HK-MoCA is a useful cognitive screening instrument for use in SVD patients.

Myocardial T2 quantitation in patients with iron overload at 3 Tesla.

PURPOSE: To investigate the feasibility of measuring myocardial T2 at 3 Tesla for assessment of tissue iron in thalassemia major and other iron overloaded patients. MATERIALS AND METHODS: A single-breathhold electrocardiogram-triggered black-blood multi-echo spin-echo (MESE) sequence with a turbo factor of 2 was implemented at 3 Tesla (T). Myocardial and liver T2 values were measured with three repeated breathholds in 8 normal subjects and 24 patients. Their values, together with the T2 values measured using a breathhold multi-echo gradient-echo sequence, were compared with those at 1.5T in the same patients. RESULTS: At 3T, myocardial T2 was found to be 39.6 +/- 7.4 ms in normal subjects. In patients, it ranged from 12.9 to 50.1 ms. "T2 and T2(*) [corrected] were observed to correlate in heart (rho = 0.93, P [corrected] < 0.0001) and liver (rho = 0.95, P < 0.0001). Myocardial T2 and T2 at 3T were also highly correlated with the 1.5T measurements. Preliminary results indicated that myocardial T2 quantitation was relatively insensitive to B1 variation, and reproducible with 3.2% intra-exam and 3.8% inter-exam variations. CONCLUSION: Myocardial T2 quantitation is feasible at 3T. Given the substantially decreased T2 and increased B0 inhomogeneity, the rapid myocardial T2 measurement protocol demonstrated here may present a robust alternative to study cardiac iron overload at 3T.

Statins for asymptomatic middle cerebral artery stenosis: The Regression of Cerebral Artery Stenosis study.

BACKGROUND: The progression of cerebral atherosclerosis increases the risk of stroke and vascular events. Given the known benefits of statins in retarding coronary and carotid atherosclerosis progression, we studied the effects of statins on asymptomatic middle cerebral artery (MCA) stenosis progression. METHODS: We conducted a randomized, double-blind, placebo-controlled study to evaluate the effects of simvastatin on the progression of MCA stenosis among stroke-free individuals who had mild to moderately elevated LDL cholesterol (3.0-5.0 mmol/l). Two hundred and twenty-seven subjects were randomized to either placebo (n = 114) or simvastatin 20 mg daily (n = 113). The severity of MCA stenosis at baseline and at the end of the study was graded by MRA into normal, minimal (<10%), mild (10-49%), moderate (50-90%) and severe (>90%). The primary outcome was the change in grading of MCA stenosis over 2 years. RESULTS: At the end of the study, the LDL cholesterol level decreased by 1.43 and 0.12 mmol/l for the active and placebo groups, respectively (p < 0.001). There was no significant difference in the proportion of patients having stable, progressive and regressive MCA stenosis between the placebo (72, 22 and 6%) and active groups (78.6, 15.5 and 5.8%). The all-cause mortality was significantly lower in the active group (n = 0) relative to the placebo group (n = 7, p = 0.014). Any clinical events were also lower in the active group (n = 5) than in the placebo group (n = 13, p = 0.052). CONCLUSIONS: Simvastatin 20 mg daily had no apparent effect upon the evolution of asymptomatic MCA stenosis over 2 years.

Long-term prognosis of Chinese patients with a lacunar infarct associated with small vessel disease: a five-year longitudinal study.

RATIONALE: Lacunar infarct associated with small vessel disease is a common stroke subtype in China and has a favorable short-term prognosis. Data on its long-term prognosis among Chinese patients are lacking. AIMS: We aimed to study its long-term prognosis and predictors for poor outcomes. DESIGN: We followed up to 75 consecutive Chinese stroke patients who had a lacunar infarct for a period of 5 years. Clinical outcomes with respect to mortality and recurrent stroke were noted. We evaluated baseline clinical and imaging predictors for such outcomes using the Cox regression analysis. STUDY OUTCOMES: Sixteen (21.3%) patients died and 12 (16%) patients had recurrent stroke during follow-up. Twenty-one (28%) patients had combined events of either death and/or recurrent stroke. Univariate Cox regression analysis showed that age, literacy, National Institute of Health Stroke Scale, incident stroke/transient ischemic attack, and white matter lesion volume predicted survival, while, age, National Institute of Health Stroke Scale, systolic blood pressure, hyperhomocysteinemia, silent lacunes, microbleeds, and white matter lesion volume predicted recurrent stroke. Multivariate Cox regression analysis showed that National Institute of Health Stroke Scale (HR 1.25, 95% CI 1.05-1.48) and white matter lesion volume (HR 1.46, 95% CI 1.11-1.92) predicted combined events of mortality and/or recurrent stroke after age adjustment. CONCLUSION: Approximately one in four patients either died and/or had recurrent stroke within 5 years after a lacunar infarct. Age, stroke severity, and volume of white matter lesion predict a poor long-term prognosis.

Effects of statins on the progression of cerebral white matter lesion: Post hoc analysis of the ROCAS (Regression of Cerebral Artery Stenosis) study.

Arteriosclerotic related cerebral white matter lesion (WML) is associated with increased risk of death, stroke, dementia, depression, gait disturbance, and urinary incontinence. We investigated the effects of statins on WML progression by performing a post hoc analysis on the ROCAS (Regression of Cerebral Artery Stenosis) study, which is a randomized, double-blind, placebo-controlled study evaluating the effects of statins upon asymptomatic middle cerebral artery stenosis progression among stroke-free individuals. Two hundreds and eight randomized subjects were assigned to either placebo (n = 102) or simvastatin 20 mg daily (n = 106) for 2 years. Baseline severity of WML was graded visually into none, mild, and severe. Volume (cm3) of WML was determined quantitatively at baseline and at end of study using a semi-automated method based on MRI. Primary outcome was the change in WML volume over 2 years. After 2 years of follow-up, there was no significant change in WML volume between the active and the placebo group as a whole. However, stratified analysis showed that for those with severe WML at baseline, the median volume increase in the active group (1.9 cm3) was less compared with that in the placebo group (3.0 cm3; P = 0.047). Linear multivariate regression analysis identified that baseline WML volume (beta = 0.63, P < 0.001) and simvastatin treatment (beta = -0.214, P = 0.043) independently predicted change in WML volume. Our findings suggest that statins may delay the progression of cerebral WML only among those who already have severe WML at baseline.

Would self-expanding stent occlude middle cerebral artery perforators?

BACKGROUND AND PURPOSE: A major concern of intracranial stenting is perforator infarction. It is unclear whether the sustained radial force of a self-expanding stent or subsequent stent restenosis would cause late occlusion of perforators. METHODS: We compared the baseline and poststent (>or=4 months) MRI scans of patients who underwent self-expanding stenting for recurrent ischemic symptoms attributed to a MCA stenosis >or=60%. New infarcts in the ipsilateral striatocapsular region were recorded. RESULTS: MCA stenting was technically successful in 23 of 24 recruited patients. No new perforator territory infarct was found in follow-up MRI scans of all recruited patients. Postoperatively, all patients reported no further TIA or stroke over a median follow-up of 15 months. CONCLUSIONS: The use of a self-expanding stent in patients with high-grade MCA stenosis may not pose a major risk to the perforators.

Emotional incontinence and executive function in ischemic stroke: a case-controlled study.

Frontal and basal ganglia infarcts and executive dysfunction are thought to be involved in the pathophysiology of poststroke emotional incontinence (PSEI). The study examined whether patients with PSEI have more frontal and/or basal ganglia infarcts and impairment in executive function. A total of 516 Chinese patients with acute ischemic stroke consecutively admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong were screened for PSEI 3 months after the index stroke. According to Kim's criteria, 39 (7.6%) had PSEI. Thirty-nine stroke patients without PSEI served as matched control group. The PSEI group had significantly more frontal and/or basal ganglia infarcts, had lower Chinese Frontal Assessment Battery scores, required more time to complete the Stroop Test, and made more omission and commission errors in the Go-NoGo test. There was no significant correlation between frontal or basal ganglia infarcts and executive function. The correlation between frontal infarct and severity of PSEI was .420. Further follow-up and functional imaging studies are warranted to explore the relationship between PSEI, brain infarcts, and executive dysfunction. (JINS, 2009, 15, 62-68.).

Poststroke depression in patients with small subcortical infarcts.

OBJECTIVES: Small subcortical infarcts (SSIs) can result from small vessel disease (SVD) and intracranial and extracranial large artery disease (LAD). No study has explored poststroke depression (PSD) in different etiological types of SSIs. METHODS: Patients with SSIs resulting from LAD and SVD were included in the study. Poststroke depression was evaluated with the 15-item version of the geriatric depression scale (GDS) 3 months after stroke. RESULTS: Of the 127 patients with SSIs, 44 had LAD and 83 had SVD. The LAD group had a significantly higher mean GDS score and higher frequency of PSD (p<0.05). The etiological type LAD was a significant independent risk factor for PSD. CONCLUSION: PSD is more common in patients with SSIs resulting from LAD. This suggests that cerebral blood perfusion may play an important role in the development of PSD.

Left ventricular systolic dyssynchrony is a predictor of cardiac remodeling after myocardial infarction.

OBJECTIVES: We sought to determine whether early assessment of left ventricular (LV) dyssynchrony by tissue Doppler imaging may predict progressive ventricular enlargement and cardiac dysfunction after acute myocardial infarction (MI). METHODS: Forty-seven patients (mean age 59.9 +/- 11.6 years) with normal QRS duration underwent tissue Doppler imaging and contrast-enhanced cardiac magnetic resonance imaging (Ce-MRI) at days 2 to 6, 3 months, and at 1 year after the index MI. Systolic dyssynchrony index (Ts-SD) was calculated from 12 LV segments, and infarct size (IS) by Ce-MRI. RESULTS: The remodeling group (n = 16) (defined as an increase in end-systolic volume > or =10% between 1 year and baseline) had greater initial IS (27.2 +/- 9.6 vs 13.7 +/- 4.1%, P < .001) and Ts-SD (50.9 +/- 12.8 vs 33.6 +/- 7.7 milliseconds, P < .001) than nonremodeling group (n = 31). At 1 year, the remodeling group had progressive increase in Ts-SD and decrease in LV ejection fraction (57.3 +/- 18.5 and 36.0 +/- 7.6%, respectively; both P < .05 vs baseline). Both Ts-SD (odds ratio 1.19 [1.07-1.32], P = .001) and IS (odds ratio 1.65 [1.19-2.29], P = .003) were shown to be independent predictors of progressive LV remodeling. A cutoff value of Ts-SD > or =45 milliseconds predicted LV remodeling at 1 year (sensitivity 90.5%, specificity 90.9%, Area-under-curve 0.907) (P = .0005). CONCLUSIONS: Left ventricular systolic dyssynchrony is a newly identified predictor of chronic LV remodeling after acute MI, which is independent and incremental to conventional assessment and IS as measured by Ce-MRI.

Multimodal computed tomography evaluation before thrombolysis in acute ischaemic stroke.

Currently, when stroke patients are offered thrombolytic therapy, their ischaemic stroke subtypes are usually unknown. Given the risk of haemorrhage that accompanies thrombolytic therapy, unselective (or undiscriminating) use of recombinant tissue plasminogen activator in patients without large-artery thromboemboli is potentially hazardous. Advances in computed tomography techniques have enabled the stroke pathophysiology to be quickly delineated by multimodal computed tomography without compromise in time for recombinant tissue plasminogen activator administration. Through description of the investigation of a typical stroke patient, we report how this technique is feasible in a regional hospital and may guide judicious use of recombinant tissue plasminogen activator.

One-stop measurement of iron deposition in the anterior pituitary, liver, and heart in thalassemia patients.

PURPOSE: To assess the feasibility of one-stop evaluation of iron load of myocardium, liver, and anterior pituitary gland in thalassemia patients. MATERIALS AND METHODS: Fifty thalassemia major patients underwent a breath-hold magnetic resonance imaging (MRI) sequence for assessment of T2* for liver and myocardium, a short axis cine trueFISP sequence covering base to apex to assess the ejection fraction of left ventricle, and a turbo spin echo T2-weighted sequence for the anterior pituitary gland. The MRI parameters were correlated with serum growth hormone, insulin growth factor-1 (IGF-1), insulin growth factor binding protein-3 (IGFBP-3), and endocrine failure. RESULTS: Ferritin was found to be associated with T2* liver (P < 0.005), T2SI (signal intensity) pituitary (P = 0.001), and T2 pituitary/fat (P = 0.001), but not with T2* heart. There was significant correlation of T2SI pituitary with IGF-1 and IGFBP-3. T2* liver (P < 0.001), T2* heart (P < 0.001), pituitary SI (P < 0.001) and pituitary/fat SI (P = 0.002) were also found to be significantly correlated with a history of hypogonadism. T2* heart was also found to be significantly correlated with IGF-1. CONCLUSION: A quick MRI protocol for assessment of T2* liver, T2* heart, and T2SI pituitary is technically feasible. This might form an objective basis to monitor the response to different organs to chelation therapy.

A case-controlled study of cognitive progression in Chinese lacunar stroke patients.

OBJECTIVE: (1) To determine and compare the rates of cognitive change using global and executive psychometric measures between lacunar stroke patients and matched controls and; (2) to identify features associated with cognitive changes in patients. METHODS: Sixty-one lacunar stroke patients and 35 demographically-matched controls were followed-up for 28.6 months (range 19.4-45.9 months) with psychometric assessments performed at baseline and follow-up. RESULTS: Lacunar stroke patients were more impaired than controls in general and executive functions at both time points. Both groups had similar stability in all psychometric tests. Patients, but not controls, exhibited a trend for improvement in general cognitive functions overtime (interaction term, p=0.084). No patient who was non-demented at baseline became demented during the study period. Two (5.7%) and five (8.2%) incident cerebrovascular events occurred among the controls and patients, respectively. Linear regression analyses performed upon patients failed to identify any predictor for the cognitive change. CONCLUSION: Similar to controls, cognition in lacunar stroke patients is stable during the first 2-3 years after the stroke. There maybe a spontaneous improvement in general cognition overtime, but this awaits confirmation by future studies.

Morphological and functional electrophysiological evidence of relative spinal cord tethering in adolescent idiopathic scoliosis.

STUDY DESIGN: Magnetic resonance (MR) imaging and multiplanar reconstruction was used to evaluate the morphology and relative position of the spinal cord in adolescent idiopathic scoliosis (AIS). OBJECTIVE: To determine the longitudinal and cross-sectional morphology of spinal cord in AIS subjects versus normal controls and their correlation with relative position of cerebellar tonsils and somatosensory cortical evoked potentials (SSEP). SUMMARY OF BACKGROUND DATA: Our previous studies revealed significantly reduced spinal cord to vertebral column length ratios in AIS patients with severe scoliotic curves suggesting the presence of disproportional growth between the neural and skeletal system. A possible neural origin of etiopathogenesis of AIS is suggested. METHODS: MR multiplanar reconstruction was performed in 97 adolescent girls (35 moderate, 26 severe AIS with right-sided thoracic/thoracolumbar curve, and 36 age-matched controls). Measurements of the ratio of anteroposterior (AP) and transverse (TS) diameter of the cord, the concave and convex lateral cord space (LCS) were obtained at the apical level in AIS subjects. Same parameters were obtained in normal controls at matched vertebral levels. Correlations were made with cord to vertebral column length ratio, cerebellar tonsil position and SSEP findings. RESULTS: AP/TS cord ratio and LCS ratio were increased in AIS subjects in the presence of reduced spinal cord to vertebral length ratio when compared with normal controls (P < 0.05). The above ratios were exaggerated in AIS subjects with abnormal SSEP findings. The AP/TS cord ratio and LCS ratio were negatively correlated with the cord to vertebral column length ratio (rho = -0.410 and -0.313, P < 0.01) and cerebellar tonsillar level (rho = -0.309 and -0.432, P < 0.01). CONCLUSION: Our study suggests presence of tethering and increased tension along the longitudinal axis of spinal cord with associated morphologic changes of cross-sectional shape and relative position of the cord.

Preliminary findings of external counterpulsation for ischemic stroke patient with large artery occlusive disease.

BACKGROUND AND PURPOSE: We aimed to investigate the feasibility and therapeutic effect of external counterpulsation (ECP) in ischemic stroke. METHODS: The trial was a randomized, crossover, assessment-blinded, proof-of-concept trial. ECP treatment consisted of 35 daily 1-hour sessions. Patients were randomized to either early (ECP weeks 1 to 7 and no ECP weeks 8 to 14) or late group (no ECP weeks 1 to 7 and ECP weeks 8 to 14). Primary outcomes were an overall change in National Institutes of Health Stroke Scale (NIHSS) and cerebral blood flow estimated by color velocity imaging quantification. Secondary outcomes were change in NIHSS, color velocity imaging quantification, favorable functional outcome (modified Rankin scale, 0 to 2), and stroke recurrence at weeks 7 and 14, respectively. RESULTS: Fifty patients were recruited. At week 7, there was a significant change in NIHSS (early 3.5 vs late 1.9; P=0.042). After adjusting for treatment sequence, ECP was associated with a favorable trend of change in NIHSS of 2.1 vs 1.3 for non-ECP (P=0.061). Changes of color velocity imaging quantification were not significant but tended to increase with ECP. At week 14, a favorable functional outcome was found in 100% of early group patients compared to 76% in the late group (P=0.022). CONCLUSIONS: ECP is feasible for ischemic stroke patients with larger artery disease.