3,140 research outputs found
Cervical artery dissection goes frequently undiagnosed.
No full textCervical artery dissection (CeAD) is a frequent cause of stroke among young patients. It is unclear how many CeADs occur asymptomatically or cause subtle and unspecific clinical symptoms. We hypothesize that CeAD remains often unrecognized. Accordingly, the incidence of CeAD might be higher and the stroke risk lower than generally assumed. Lack of CeAD-indicating clinical symptoms is regarded as the main cause of missed diagnoses. We further hypothesize that underrepresentation of asymptomatic and oligosymptomatic patients in CeAD studies may have biased the association between ischemia and local symptoms in CeAD patients as well as the associations of CeAD with risk factors or co-morbidities. We finally hypothesize that symptomatic CeAD may be preceded by an initial asymptomatic phase. According to this final hypothesis, the time of onset of CeAD should be considered uncertain. The issue of unrecognized CeAD is relevant, as it may affect the associations between CeAD and putative risk factors. Furthermore, the existence of clinically silent CeADs may explain why recurrent and familial CeAD have been rarely observed
Gender and cervical artery dissection.
No full textBackground and purpose: To analyze previously established gender differences in cervical artery dissection (CeAD). Methods: This case-control study is based on the CADISP (Cervical Artery Dissection and Ischemic Stroke Patients) population comprising 983 consecutive CeAD patients (mean age: 44.1±9.9years) and 658 control patients with a non-CeAD ischemic stroke (IS) (44.5±10.5years). Results: Cervical artery dissection was more common in men (56.7% vs. 43.3%, P<0.001) and men were older (46.4 vs. 41.0years, P<0.001). We assessed putative risk factors for CeAD including vascular risk factors, recent cervical trauma, pregnancies, and infections. All gender differences in the putative risk factors and outcome were similar in the CeAD and the non-CeAD IS groups. Conclusion: Our analysis of the largest collection of CeAD patients to date confirms male predominance and differences in age at dissection between men and women. Gender differences in putative risk factors may explain the higher frequency of CeAD in men and their older age, but the putative risk factors are probably not specific for CeAD. © 2011 The Author(s). European Journal of Neurology © 2011 EFNS.SCOPUS: ar.jFLWINinfo:eu-repo/semantics/publishe
Synthesis optimization and charge carrier transfer mechanism in LiLuSiO<sub>4</sub>:Ce, Tm storage phosphor
No full textLiLuSiO4:Ce and LiLuSiO4:Ce, Tm show very efficient charge carrier storage properties upon beta irradiation after samples have received treatment in vacuum. They outperform the commercial storage phosphor BaFBr(I):Eu2+ in many aspects. The influence of the synthesis conditions, Ce and Tm concentration, nonstoichiometry and codoping with Ca, Hf, Al and Ge are reported. Based on the results of the synthesis optimization, thermoluminescence (TL) emission and TL excitation spectra a mechanism of charge carrier transfer, storage, and recombination during irradiation and thermal or optical readout is proposed.Accepted Author ManuscriptRST/Fundamental Aspects of Materials and EnergyRST/Luminescence Material
Towards understanding seasonal variability in cervical artery dissection (CeAD).
No full textCervical artery dissection (CeAD) occurs more often in autumn or winter than in spring or summer. We searched for clinical variables associated with this seasonality by comparing CeAD patients with onset of symptoms in autumn–winter (September 22–March 21) versus those with first CeAD symptom in spring–summer (March 22–September 21). We performed a cross-sectional study using data from the multicenter CADISP (Cervical Artery Dissection and Ischemic Stroke Patients) registry. Age- and sex-matched patients with ischemic stroke attributable to a cause other than CeAD (non-CeAD patients) were analyzed to study the specificity of our findings. Autumn–winter CeAD patients had a higher median brachial pulse pressure at admission (55 vs. 52 mmHg; p = 0.01) and more recent infections (22.0% vs. 16.6%; p = 0.047), but prevalence of trauma was not associated with seasonal onset. Multivariable logistic regression analysis revealed that higher pulse pressure was significantly associated with autumn–winter CeAD (p = 0.01), while age, gender, history of hypertension, recent infection, and recent trauma were not. No association between pulse pressure and seasonal occurrence was found in non-CeAD ischemic stroke patients. Increased pulse pressure was associated with the higher frequency of CeAD in autumn or winter
Stroke in first-degree relatives of patients with cervical artery dissection
No full textBACKGROUND AND PURPOSE: Patients with ischaemic stroke (IS) caused by a spontaneous cervical artery dissection (CeAD) worry about an increased risk for stroke in their families. The occurrence of stroke in relatives of patients with CeAD and in those with ischaemic stroke attributable to other (non-CeAD) causes were compared.
METHODS: The frequency of stroke in first-degree relatives (family history of stroke, FHS) was studied in IS patients (CeAD patients and age- and sex-matched non-CeAD patients) from the Cervical Artery Dissection and Ischemic Stroke Patients (CADISP) database. FHS ≤ 50 and FHS > 50 were defined as having relatives who suffered stroke at the age of ≤50 or >50 years. FHS ≤ 50 and FHS > 50 were studied in CeAD and non-CeAD IS patients and related to age, sex, number of siblings, hypertension, hypercholesterolemia, smoking and body mass index (BMI).
RESULTS: In all, 1225 patients were analyzed. FHS ≤ 50 was less frequent in CeAD patients (15/598 = 2.5%) than in non-CeAD IS patients (38/627 = 6.1%) (P = 0.003; odds ratio 0.40, 95% confidence interval 0.22-0.73), also after adjustment for age, sex and number of siblings (P = 0.005; odds ratio 0.42, 95% confidence interval 0.23-0.77). The frequency of FHS > 50 was similar in both study groups. Vascular risk factors did not differ between patients with positive or negative FHS ≤ 50. However, patients with FHS > 50 were more likely to have hypertension and higher BMI.
CONCLUSION: Relatives of CeAD patients had fewer strokes at a young age than relatives of non-CeAD IS stroke patients
Clinical import of Horner syndrome in internal carotid and vertebral artery dissection.
No full textOBJECTIVE: To study the prognostic importance of Horner syndrome (HS) in patients with internal carotid artery dissection (ICAD) or vertebral artery dissection (VAD).
METHODS: In this observational study, characteristics and outcome of patients with ICAD or VAD from the CADISP (Cervical Artery Dissection and Ischemic Stroke Patients) database were analyzed. The presence of HS was systematically assessed using a standardized questionnaire. Patients with HS (HS+) were compared with HS- patients. Crude odds ratios (ORs) with 95% confidence intervals and ORs adjusted for age, sex, center, arterial occlusion, bilateral dissection, stroke severity, and type of antithrombotic treatment were calculated.
RESULTS: We analyzed 765 patients (n = 496 with ICAD, n = 269 with VAD, n = 303 prospective, n = 462 retrospective). HS was present in 191 (38.5%) of the patients with ICAD and 36 (13.4%) of the patients with VAD (p < 0.001). HS+ ICAD patients presented less often with stroke or TIA (p < 0.001), less often had bilateral (p = 0.019) or occlusive (p = 0.001) dissections, and had fewer severe strokes (p = 0.041) than HS- ICAD patients. HS+ ICAD patients had a better functional 3-month outcome than those without HS (ORcrude = 4.0 [2.4-6.7]), and also after adjustment for outcome-relevant covariates (ORadjusted = 2.0 [1.1-4.0]). HS+ ICAD patients were less likely to have new strokes than HS- ICAD patients (p = 0.039). HS+ VAD patients more often had vessel occlusion (p = 0.014) than HS- patients but did not differ in any of the other aforementioned variables.
CONCLUSION: In patients with ICAD, HS is an easily assessable marker that might indicate a more benign clinical course. HS had no prognostic meaning in patients with VAD
Energy efficiency in double disc refining. Influence of intensity by segment design
No full textThe goal with this work was to study the effect of segment design on electrical energy consumption and pulp quality in double disc TMP production. Mill scale trials were performed with refiner segments from Metso, which were designed based on the fluid dynamics theory. The calculated intensity for the different segments was related to the measured pulp quality. Refining with the high intensity segments (Turbine (TM)) produced pulp with similar tensile index and a significantly higher specific light scattering coefficient at certain specific energy consumption when compared with the reference segments. One drawback with the high intensity segments was the limited operating window due to fibre cutting. The trials showed that segment performance can be modelled, which facilitates the development of new segment designs
Elevated peripheral leukocyte counts in acute cervical artery dissection.
No full textBACKGROUND AND PURPOSE: It has been suggested that inflammation may play a role in the development of cervical artery dissection (CeAD), but evidence remains scarce.
METHODS: A total of 172 patients were included with acute (< 24 h) CeAD and 348 patients with acute ischaemic stroke (IS) of other (non-CeAD) causes from the Cervical Artery Dissection and Ischemic Stroke Patients (CADISP) study, and 223 age- and sex-matched healthy control subjects. White blood cell (WBC) counts collected at admission were compared across the three groups.
RESULTS: Compared with healthy control subjects, CeAD patients and non-CeAD stroke patients had higher WBC counts (P 10 000/μl than non-CeAD stroke patients (38.4% vs. 23.0%, P < 0.001) and healthy controls (38.4% vs. 8.5%, P < 0.001). WBC counts were higher in CeAD (9.4 ± 3.3) than in IS of other causes (large artery atherosclerosis, 8.7 ± 2.3; cardioembolism, 8.2 ± 2.8; small vessel disease, 8.4 ± 2.4; undetermined cause, 8.8 ± 3.1; P = 0.022). After adjustment for age, sex, stroke severity and vascular risk factors in a multiple regression model, elevated WBC count remained associated with CeAD, as compared with non-CeAD stroke patients [odds ratio (OR) = 2.56; 95% CI 1.60-4.11; P < 0.001) and healthy controls (OR = 6.27; 95% CI 3.39-11.61; P < 0.001).
CONCLUSIONS: Acute CeAD was associated with particularly high WBC counts. Leukocytosis may reflect a pre-existing inflammatory state, supporting the link between inflammation and CeAD
Stroke in first-degree relatives of patients with cervical artery dissection.
No full textBACKGROUND AND PURPOSE: Patients with ischaemic stroke (IS) caused by a spontaneous cervical artery dissection (CeAD) worry about an increased risk for stroke in their families. The occurrence of stroke in relatives of patients with CeAD and in those with ischaemic stroke attributable to other (non-CeAD) causes were compared.
METHODS: The frequency of stroke in first-degree relatives (family history of stroke, FHS) was studied in IS patients (CeAD patients and age- and sex-matched non-CeAD patients) from the Cervical Artery Dissection and Ischemic Stroke Patients (CADISP) database. FHS ≤ 50 and FHS > 50 were defined as having relatives who suffered stroke at the age of ≤50 or >50 years. FHS ≤ 50 and FHS > 50 were studied in CeAD and non-CeAD IS patients and related to age, sex, number of siblings, hypertension, hypercholesterolemia, smoking and body mass index (BMI).
RESULTS: In all, 1225 patients were analyzed. FHS ≤ 50 was less frequent in CeAD patients (15/598 = 2.5%) than in non-CeAD IS patients (38/627 = 6.1%) (P = 0.003; odds ratio 0.40, 95% confidence interval 0.22-0.73), also after adjustment for age, sex and number of siblings (P = 0.005; odds ratio 0.42, 95% confidence interval 0.23-0.77). The frequency of FHS > 50 was similar in both study groups. Vascular risk factors did not differ between patients with positive or negative FHS ≤ 50. However, patients with FHS > 50 were more likely to have hypertension and higher BMI.
CONCLUSION: Relatives of CeAD patients had fewer strokes at a young age than relatives of non-CeAD IS stroke patients
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