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1.
Acta Neurochir Suppl ; 126: 79-84, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29492537

RESUMO

OBJECTIVE: Previously we described the method of continuous intracranial pressure (ICP) estimation using arterial blood pressure (ABP) and cerebral blood flow velocity (CBFV). The model was constructed using reference patient data. Various individual calibration strategies were used in the current attempt to improve the accuracy of this non-invasive ICP (nICP) assessment tool. MATERIALS AND METHODS: Forty-one patients (mean, 52 years; range, 18-77 years) with severe brain injuries were studied. CBFV in the middle cerebral artery (MCA), ABP and invasively assessed ICP were simultaneously recorded for 1 h. Recording was repeated at days 2, 4 and 7. In the first recording, invasively assessed ICP was recorded to calibrate the nICP procedure by means of either a constant shift of nICP (snICP), a constant shift of nICP/ABP ratio (anICP) or by including this recording for a model reconstruction (cnICP). At follow-up days, the calibrated nICP procedures were applied and the results compared to the original nICP. RESULTS: In 76 follow-up recordings, the mean differences (Bias), the SD and the mean absolute differences (ΔICP) between ICP and the nICP methods were (in mmHg): nICP, -5.6 ± 5.72, 6.5; snICP, +0.7 ± 6.98, 5.5, n.s.; anICP, +1.0 ± 7.22, 5.6, n.s.; cnICP, -3.4 ± 5.68, 5.4, p < 0.001. In patients with craniotomy (n = 19), the nICP was generally higher than ICP. This overestimation could be reduced by cnICP calibration, but not completely avoided. DISCUSSION: Constant shift calibrations (snICP, anICP) decrease the Bias to ICP, but increase SD and, therefore, increase the 95% confidence interval (CI = 2 × SD). This calibration method cannot be recommended. Compared to nICP, the cnICP method reduced the Bias and slightly reduced SD, and showed significantly decreased ΔICP. Compared to snICP and anICP, the Bias was higher. This effect was probably caused by the patients with craniotomy. CONCLUSION: The cnICP calibration method using initial recordings for model reconstruction showed the best results.


Assuntos
Pressão Arterial/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Calibragem , Circulação Cerebrovascular/fisiologia , Hipertensão Intracraniana/diagnóstico por imagem , Pressão Intracraniana/fisiologia , Artéria Cerebral Média/diagnóstico por imagem , Hemorragia Subaracnóidea/diagnóstico por imagem , Adolescente , Adulto , Idoso , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/fisiopatologia , Feminino , Humanos , Hipertensão Intracraniana/complicações , Hipertensão Intracraniana/fisiopatologia , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/fisiopatologia , Ultrassonografia Doppler Transcraniana/métodos , Adulto Jovem
2.
Acta Neurochir Suppl ; 122: 181-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27165903

RESUMO

BACKGROUND: Cerebral autoregulation (CA) is a mechanism that compensates for variations in cerebral perfusion pressure (CPP) by changes in cerebral blood flow resistance to keep the cerebral blood flow constant. In this study, the relationship between lethal outcome during hospitalisation and the autoregulation-related indices PRx and Mx was investigated. MATERIALS AND METHODS: Thirty patients (aged 18-77 years, mean 53 ± 16 years) with severe cerebral diseases were studied. Cerebral blood flow velocity (CBFV), arterial blood pressure (ABP) and intracranial pressure (ICP) were repeatedly recorded. CA indices were calculated as the averaged correlation between CBFV and CPP (Mx) and between ABP and ICP (PRx). Positive index values indicated impairment of CA. RESULTS: Six patients died in hospital. In this group both PRx and Mx were significantly higher than in the group of survivors (PRx: 0.41 ± 0.33 vs 0.09 ± 0.25; Mx: 0.28 ± 0.40 vs 0.03 ± 0.21; p = 0.01 and 0.04, respectively). PRx and Mx correlated significantly with Glasgow Outcome Scale (GOS) score (PRx: R = -0.40, p < 0.05; Mx: R = -0.54, p < 0.005). PRx was the only significant risk factor for mortality (p < 0.05, logistic regression). CONCLUSION: Increased PRx and Mx were associated with risk of death in patients with severe cerebral diseases. The relationship with mortality was more pronounced in PRx, whereas Mx showed a better correlation with GOS score.


Assuntos
Encefalopatias/fisiopatologia , Circulação Cerebrovascular/fisiologia , Homeostase , Pressão Intracraniana/fisiologia , Adolescente , Adulto , Idoso , Encefalopatias/mortalidade , Lesões Encefálicas Traumáticas/mortalidade , Lesões Encefálicas Traumáticas/fisiopatologia , Hemorragia Cerebral/mortalidade , Hemorragia Cerebral/fisiopatologia , Encefalite/mortalidade , Encefalite/fisiopatologia , Feminino , Humanos , Hipóxia Encefálica/mortalidade , Hipóxia Encefálica/fisiopatologia , Infarto da Artéria Cerebral Média/mortalidade , Infarto da Artéria Cerebral Média/fisiopatologia , Hemorragias Intracranianas/mortalidade , Hemorragias Intracranianas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia , Monitorização Fisiológica , Prognóstico , Estudos Retrospectivos , Trombose dos Seios Intracranianos/mortalidade , Trombose dos Seios Intracranianos/fisiopatologia , Hemorragia Subaracnóidea/mortalidade , Hemorragia Subaracnóidea/fisiopatologia , Hemorragia Subaracnoídea Traumática/mortalidade , Hemorragia Subaracnoídea Traumática/fisiopatologia , Ultrassonografia Doppler Transcraniana , Adulto Jovem
3.
Acta Neurochir Suppl ; 122: 69-73, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27165880

RESUMO

BACKGROUND: In a previously introduced mathematical model, intracranial pressure (ICP) was noninvasively assessed using cerebral blood flow velocity (CBFV) and arterial blood pressure (ABP). In this study this method is evaluated using new data from patients with traumatic brain injury (TBI). MATERIALS AND METHODS: Three hundred fifteen data recordings of 137 patients (114 men; age 14-78 years, mean age 37 ± 17 years) with severe TBI were studied. CBFV, ABP, and invasively assessed ICP were simultaneously recorded for 1 h. Noninvasive ICP (nICP) was calculated and compared with ICP. RESULTS: On 315 recordings, average deviation between ICP and nICP (± standard deviation) was 4.9 ± 3.3 mmHg. The standard deviation of differences (ICP - nICP) was 5.6 mmHg. The 95 % confidence interval of ICP prediction ranged from -9.6 to 12.3 mmHg. Mean ICP was 16.7 mmHg and mean nICP was 18.0 mmHg. When nICP was adjusted by their difference 1.3 mmHg (nICPadj = nICP - 1.3), the 95 % confidence limits of ICP prediction became ±11.0 mmHg. In recordings with highly dynamic ICP signals (n = 27), ICP and nICP correlated on average with R = 0.51 ± 0.47. CONCLUSIONS: nICP assessment showed reasonable accuracy and may be used in clinical studies of patients without any indication for ICP probe implantation.


Assuntos
Velocidade do Fluxo Sanguíneo , Lesões Encefálicas Traumáticas/fisiopatologia , Circulação Cerebrovascular , Hipertensão Intracraniana/diagnóstico por imagem , Pressão Intracraniana , Artéria Cerebral Média/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Adolescente , Adulto , Idoso , Lesões Encefálicas Traumáticas/complicações , Feminino , Humanos , Hipertensão Intracraniana/diagnóstico , Hipertensão Intracraniana/etiologia , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Índices de Gravidade do Trauma , Adulto Jovem
4.
J Clin Monit Comput ; 30(3): 367-75, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26085437

RESUMO

Indexes PRx and Mx have been formerly introduced to assess cerebral autoregulation and have been shown to be associated with 3-month clinical outcome. In a mixed cohort of neurocritical care patients, we retrospectively investigated the impact of selected clinical characteristics on this association. Forty-one patients (18-77 years) with severe traumatic (TBI, N = 20) and non-traumatic (N = 21) brain injuries were studied. Cerebral blood flow velocity, arterial blood pressure and intracranial pressure were repeatedly recorded during 1-h periods. Calculated PRx and Mx were correlated with 3-month clinical outcome score of modified Rankin Scale (mRS) in different subgroups with specific clinical characteristics. Both PRx and Mx correlated significantly with outcome (PRx: r = 0.38, p < 0.05; AUC = 0.64, n.s./Mx: r = 0.48, p < 0.005; AUC = 0.80, p < 0.005) in the overall group, and in patients with hemicraniectomy (N = 17; PRx: r = 0.73, p < 0.001; AUC = 0.89, p < 0.01/Mx: r = 0.69, p < 0.005; AUC = 0.87, p < 0.05). Mx, not PRx, correlated significantly with mRS in patients with heart failure (N = 17; r = 0.69, p < 0.005; AUC = 0.92, p < 0.005), and in non-traumatic patients (r = 0.49, p < 0.05; AUC = 0.79, p < 0.05). PRx, not Mx, correlated significantly with mRS in TBI patients (r = 0.63, p < 0.01; AUC = 0.89, p < 0.01). Both indexes did not correlate with mRS in diabetes patients (N = 15), PRx failed in hypocapnic patients (N = 26). Both PRx and Mx were significantly associated with 3-month clinical outcome, even in patients with hemicraniectomy. PRx was more appropriate for TBI patients, while Mx was better suited for non-traumatic patients and patients with heart failure. Prognostic values of indexes were affected by diabetes (both Mx and PRx) and hypocapnia (PRx only).


Assuntos
Lesões Encefálicas/fisiopatologia , Circulação Cerebrovascular/fisiologia , Monitorização Fisiológica/métodos , Adolescente , Adulto , Idoso , Pressão Arterial , Velocidade do Fluxo Sanguíneo , Lesões Encefálicas Traumáticas/fisiopatologia , Estudos de Coortes , Cuidados Críticos , Feminino , Homeostase , Humanos , Pressão Intracraniana/fisiologia , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/estatística & dados numéricos , Monitorização Neurofisiológica/métodos , Monitorização Neurofisiológica/estatística & dados numéricos , Prognóstico , Estudos Retrospectivos , Ultrassonografia Doppler Transcraniana , Adulto Jovem
5.
Z Psychosom Med Psychother ; 59(4): 356-68, 2013.
Artigo em Alemão | MEDLINE | ID: mdl-24307335

RESUMO

OBJECTIVES: Dysfunctional parenting styles represent a risk factor for the development of psychological disturbances. The present study investigated the differential validity of the German language Fragebogen zur Erfassung dysfunktionaler Erziehungsstile (FDEB; Measurement of Parental Styles, MOPS) and determined whether different forms of psychological disorders are associated with specific patterns of parenting styles. METHODS: 145 inpatients, 108 outpatients and a control group of 633 representative individuals from the general population were investigated by adapting the FDEB. RESULTS: A comparison of dysfunctional parenting styles showed different distress levels within the diagnostic groups: Patients suffering from depression reported high levels of maternal indifference and over protectiveness together with an abusive rearing behavior on the part of both parents. Patients with anxiety disorders reported having overprotective mothers. Bulimic patients as well as those with personality disorders significantly exhibited stress in almost all areas. However, anorexic patients did not differ significantly from the control group, which appeared to be the least affected of all. CONCLUSION: The FDEB showed a satisfactory differential validity. There was evidence that specific patterns of dysfunctional parenting styles were associated with different diagnostic groups.


Assuntos
Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Poder Familiar/psicologia , Adulto , Anorexia Nervosa/diagnóstico , Anorexia Nervosa/psicologia , Bulimia/diagnóstico , Bulimia/psicologia , Criança , Maus-Tratos Infantis/diagnóstico , Maus-Tratos Infantis/psicologia , Educação Infantil , Comparação Transcultural , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Relações Mãe-Filho , Transtornos da Personalidade/diagnóstico , Transtornos da Personalidade/psicologia , Psicometria/estatística & dados numéricos , Valores de Referência , Reprodutibilidade dos Testes , Inquéritos e Questionários
6.
Acta Neurochir Suppl ; 114: 121-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22327676

RESUMO

INTRODUCTION: An existing monitoring database of brain signal recordings in patients with head injury has been re-evaluated with regard to the accuracy of estimation of non-invasive ICP (nICP) and its components, with a particular interest in the implications for outcome after head injury. METHODS: Middle cerebral artery blood flow velocity (FV), ICP and arterial blood pressure (ABP) were recorded. Non-invasive ICP (nICP) was calculated using a mathematical model. Other signals analysed included components of ICP (n" indicates non-invasive): ICP pulse amplitude (Amp, nAmp), amplitude of the respiratory component (Resp, nResp), amplitude of slow vasogenic waves of ICP (Slow, nSlow) and index of compensatory reserve (RAP, nRAP). Mean values of analysed signals were compared against each other and between patients who died and survived. RESULTS: The correlation between ICP and nICP was moderately strong, R = 0.51 (95% prediction interval [PI] 17 mm Hg). The components of nICP and ICP were also moderately correlated with each other: the strongest correlation was observed for Resp vs. nResp (r = 0.66), while weaker for Amp vs. nAmp (r = 0.41). Non-invasive pulse amplitude of ICP showed the strongest association with outcome, with the -difference between those who survived and those who died reaching a significance level of p < 0.000001. DISCUSSION: When compared between patients who died and who survived mean nAmp showed the greatest difference, suggesting its potential to predict mortality after TBI.


Assuntos
Lesões Encefálicas/diagnóstico , Lesões Encefálicas/fisiopatologia , Circulação Cerebrovascular/fisiologia , Pressão Intracraniana/fisiologia , Estatística como Assunto , Adolescente , Adulto , Pressão Sanguínea/fisiologia , Lesões Encefálicas/mortalidade , Feminino , Escala de Resultado de Glasgow , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/fisiopatologia , Ultrassonografia Doppler Transcraniana , Adulto Jovem
7.
J Neurol ; 265(1): 165-177, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29185050

RESUMO

PURPOSE: To develop specific diagnostic ultrasound (US) models for hereditary motor and sensory neuropathies (HMSN) in patients with primarily demyelinating or axonal polyneuropathies (PNP) according to standard nerve conduction studies (NCS) criteria. METHODS: Single-centre, examiner-blinded cross-sectional study in acquired PNP (consecutive recruitment strategy) and HMSN patients (convenience sample). Allocation into demyelinating or axonal phenotype via easily applicable NCS criteria. Assessment of single measurements by receiver-operating curve (ROC) analysis, development of diagnostic models based on the best measurement values in ROC. RESULTS: Of 85 enrolled subjects, 53 (62%) had HMSN and 32 (38%) acquired PNPs, and 60 subjects (71%) had demyelinating and 25 (29%) axonal PNP. ROC area under the curve of means of the z-transformed 5 best measurement values was 0.87 for demyelinating and 0.99 for axonal HMSN. Diagnostic models showed high accuracy for both demyelinating (84% sensitivity, 86% specificity) and axonal HMSN (100% sensitivity and specificity). As a measure of variability of morphologic changes, standard deviations of z-transformed measurements were compared for acquired PNP and HMSN. In contrast to previous reports of more homogenous nerve enlargements in HMSN, standard deviations were higher in HMSN than in acquired PNP. Additionally, the performance of previously published models for the diagnosis of HMSN in demyelinating PNP was compared. Previously published models showed lower sensitivities (50-58%), but comparable specificities (91-100%) when applied to NCS-criteria defined demyelinating PNP group. CONCLUSION: Diagnostic ultrasound models for HMSN in patients with demyelinating or axonal neuropathies show high accuracy and can contribute to differential diagnosis in clinical routine.


Assuntos
Axônios/patologia , Doenças Desmielinizantes/diagnóstico por imagem , Doenças Desmielinizantes/etiologia , Neuropatia Hereditária Motora e Sensorial/diagnóstico por imagem , Neuropatia Hereditária Motora e Sensorial/fisiopatologia , Ultrassonografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Curva ROC , Estudos Retrospectivos
8.
Stroke ; 37(1): 139-44, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16306456

RESUMO

BACKGROUND AND PURPOSE: Patients with stroke are at substantial risk of thromboembolic complications and therefore require antithrombotic prophylaxis. To show the noninferiority of the low-molecular-weight heparin certoparin to unfractionated heparin (UFH) for the prevention of thromboembolic complications, we performed a randomized, double-blind, active-controlled multicenter trial in patients with acute ischemic stroke. METHODS: Overall, 545 patients were randomized within 24 hours of stroke onset to treatment with certoparin (3000 U anti-Xa OD; n=272) or UFH (5000 U TID; n=273) for 12 to 16 days. Patients with paresis of a leg and an National Institutes of Health Stroke Scale score of 4 to 30 points were included. The primary end point was a composite outcome of proximal deep vein thrombosis, pulmonary embolism, or death related to venous thromboembolism during treatment. Computed tomography was performed at trial entry, after 7 days, and when clinical deterioration occurred. RESULTS: The per-protocol analysis revealed 17 (7.0%) primary events in the certoparin group compared with 24 (9.7%) in the UFH group, thereby demonstrating noninferiority (P=0.0011), confirmed by intention-to-treat analysis (6.6% versus 8.8%; P=0.008). Major bleeding occurred during treatment in 3 patients allocated to certoparin (1.1%) and 5 patients allocated to UFH (1.8%). CONCLUSIONS: Certoparin (3000 U anti-Xa OD) is at least as effective and safe as UFH (TID) for the prevention of thromboembolic complications in patients with acute ischemic stroke.


Assuntos
Heparina de Baixo Peso Molecular/uso terapêutico , Heparina/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Tromboembolia/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Humanos , Isquemia/terapia , Pessoa de Meia-Idade , Modelos Estatísticos , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/mortalidade , Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/patologia , Tromboembolia/mortalidade , Tromboembolia/patologia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Trombose Venosa/tratamento farmacológico
9.
J Neurol ; 263(11): 2196-2206, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27502085

RESUMO

The objective of this study is to compare the diagnostic accuracy of nerve ultrasound (US) and nerve conduction studies (NCS) for acquired non-entrapment peripheral neuropathies (PNP) and hereditary motor and sensory neuropathies (HMSN) in a routine clinical setting. The methods are based on a single-center, prospective, examiner-blinded cross-sectional study on three subject groups of healthy controls, PNP (both enrolled by a consecutive recruitment strategy), and HMSN patients (convenience sample). A clinical reference standard based on the neuropathy impairment (NIS) and neuropathy symptoms scores (NSS) was used for PNP as the external validation criterion. Diagnostic accuracy was assessed by receiver-operating curve (ROC) analyses of single-nerve measurements and logit models. Of a total of 676 consecutively screened subjects, 107 (15.8 %) were recruited, of which 36 (33.6 %) had a PNP. HMSN group consisted of 53 subjects (30 subjects (56.6 %) with genetic confirmation). AUCs of best diagnostic logit models to distinguish between controls and PNP patients were 0.86 for US and 0.97 for NCS corresponding to an equivalent specificity [US 93 % (95 % CI: 83-98 %), NCS 89 % (95 % CI: 78-95 %)], but inferior sensitivity of US [US 56 % (95 % CI: 35-74 %), NCS 97 % (95 % CI: 84-100 %)]. For differentiation between PNP and HMSN, both methods had equivalent AUCs of 0.95 corresponding to similar sensitivities/specificities. Simpler diagnostic models based on measurement protocols feasible for clinical routine revealed similar diagnostic accuracies. US has an inferior sensitivity than NCS for acquired PNP, but comparable specificity. For identification of HMSN in a PNP population, US and NCS show comparable performance.


Assuntos
Neuropatia Hereditária Motora e Sensorial/diagnóstico por imagem , Neuropatia Hereditária Motora e Sensorial/fisiopatologia , Ultrassonografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Exame Neurológico , Curva ROC , Estudos Retrospectivos
10.
Circulation ; 109(8): 1010-5, 2004 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-14769704

RESUMO

BACKGROUND: Chlamydia pneumoniae (Cp) infection has been associated with atherosclerosis and cardiovascular events. There are controversial results regarding the beneficial effects of antibiotic therapy on future cardiovascular end points. METHODS AND RESULTS: We determined the long-term effect of a 30-day roxithromycin therapy on intima-to-media thickness (IMT) progression of the common carotid artery in 272 consecutive Cp-positive and Cp-negative patients with ischemic stroke in a prospective, double-blind, randomized trial with a follow-up of 4 years. Cp IgG (> or =1:64) or IgA (> or =1:16) antibodies were initially found in 125 (46%) patients. During the 3 years before antibiotic therapy, Cp-positive patients showed an enhanced IMT progression even after adjustment for other cardiovascular risk factors (0.12 [0.11 to 0.14] versus 0.07 [0.05 to 0.09] mm/year; P<0.005). The 62 Cp-positive patients given roxithromycin showed a reduced IMT progression during the first 2 years compared with the Cp-positive patients without therapy (0.07 [0.045 to 0.095] versus 0.11 [0.088 to 0.132] mm/year; P<0.01). However, IMT progression increased again during the third and fourth year to similar values as before treatment. No significant difference in the occurrence of future cardiovascular events was found between both groups during follow-up. CONCLUSIONS: The only limited positive impact of antibiotic therapy on early atherosclerosis progression in Cp-positive patients observed in our study may explain the negative results of most antibiotic trials on clinical end points.


Assuntos
Doenças das Artérias Carótidas/complicações , Infecções por Chlamydophila/tratamento farmacológico , Roxitromicina/uso terapêutico , Idoso , Anticorpos Antibacterianos/sangue , Isquemia Encefálica/etiologia , Artéria Carótida Primitiva/patologia , Infecções por Chlamydophila/complicações , Infecções por Chlamydophila/diagnóstico , Chlamydophila pneumoniae/imunologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Tábuas de Vida , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Recidiva , Fatores de Risco , Análise de Sobrevida , Resultado do Tratamento , Túnica Íntima/patologia , Túnica Média/patologia
11.
Circulation ; 106(19): 2428-33, 2002 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-12417538

RESUMO

BACKGROUND: Chlamydia pneumoniae (Cp) infection has been associated with atherosclerosis, and a beneficial effect of antibiotic therapy on future cardiovascular events was described. METHODS AND RESULTS: We evaluated the effect of roxithromycin therapy (150 mg twice daily for 30 days) on the progression of the intima-to-media thickness (IMT) of the common carotid artery using duplex ultrasonography in a prospective and randomized trial with a follow-up of 2 years in 272 consecutive patients with ischemic stroke aged over 55 years in whom the first IMT measurement and Cp testing (IgG and IgA) were performed at least 3 years before the roxithromycin treatment. Cp IgG antibodies (> or =1:64) were initially found in 123 (45%) patients and IgA antibodies (> or =1:16) in 112 (41%) patients. During the 3 years before antibiotic therapy, Cp-positive patients showed an enhanced IMT progression, even after adjustment for other cardiovascular risk factors (0.12 [95% CI, 0.11 to 0.14] versus 0.07 [0.05 to 0.09] mm/year; P<0.005). The 62 Cp-positive patients given roxithromycin showed a significantly decreased IMT progression after 2 years compared with the Cp-positive patients without therapy (0.07 [0.045 to 0.095] versus 0.11 [0.088 to 0.132] mm/year; P<0.01). No significant difference in the occurrence of future cardiovascular events was found between both groups during follow-up. No change of IMT was observed in Cp-negative patients given roxithromycin (n=74) compared with those without therapy (0.06 [0.03 to 0.09] versus 0.07 [0.05 to 0.09] mm/year). CONCLUSIONS: Our findings suggest a positive impact of antibiotic therapy on early atherosclerosis progression in Cp-seropositive patients with cerebrovascular disease.


Assuntos
Antibacterianos/uso terapêutico , Doenças das Artérias Carótidas/tratamento farmacológico , Infecções por Chlamydophila/tratamento farmacológico , Chlamydophila pneumoniae/isolamento & purificação , Roxitromicina/uso terapêutico , Idoso , Anticorpos Antibacterianos/sangue , Proteína C-Reativa/análise , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/efeitos dos fármacos , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/microbiologia , Infecções por Chlamydophila/sangue , Infecções por Chlamydophila/complicações , Progressão da Doença , Feminino , Seguimentos , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Risco , Testes Sorológicos , Análise de Sobrevida , Resultado do Tratamento , Túnica Íntima/diagnóstico por imagem , Túnica Íntima/efeitos dos fármacos , Túnica Média/diagnóstico por imagem , Túnica Média/efeitos dos fármacos , Ultrassonografia Doppler Dupla
12.
Stroke ; 34(1): 84-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12511755

RESUMO

BACKGROUND AND PURPOSE: A mathematical model has previously been introduced to estimate noninvasively intracranial pressure (nICP). In the present multicenter study, we investigated the ability of model to adapt to the state of cerebral autoregulation (SCA). This modification was intended to improve the quality of nICP estimation and noninvasive assessment of pressure reactivity of the cerebrovascular system. METHODS: We studied 145 patients after severe head injuries or stroke. All patients had direct ICP, arterial blood pressure (ABP), and transcranial Doppler middle cerebral artery blood flow velocity (FV) monitored. The SCA was assessed by moving correlation (Mx index) of cerebral perfusion pressure (CPP=ABP-ICP) and cerebral blood flow velocity and correlation of ABP and ICP (PRx index). nICP was calculated from ABP and FV waveforms. When nICP was used instead of ICP, the SCA was continuously estimated, and the model was dynamically adapted to the SCA. RESULTS: High and moderate correlations between invasively (Mx, PRx) and noninvasively (nMx, nPRx) estimated autoregulation indexes were observed (Mx: R=0.90, P<0.001; PRx: R=0.62, P<0.001). Values of Mx and nMx indicated contradictory SCA in 4 of 167 evaluated recordings; values of PRx and nPRx were contradictory in 27 recordings. When the model was adapted to the SCA, the mean error of ICP estimation decreased significantly (P<0.005). CONCLUSIONS: Continuous adaptation of the model to SCA improves the accuracy of noninvasive estimation of ICP and ICP dynamics. The same model provides a noninvasive and continuous assessment of SCA.


Assuntos
Circulação Cerebrovascular , Traumatismos Craniocerebrais/fisiopatologia , Pressão Intracraniana , Adolescente , Adulto , Idoso , Pressão Sanguínea , Encéfalo/fisiopatologia , Criança , Pré-Escolar , Traumatismos Craniocerebrais/diagnóstico por imagem , Feminino , Homeostase , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Modelos Teóricos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Ultrassonografia Doppler Transcraniana
13.
J Nucl Med ; 44(5): 671-81, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12732667

RESUMO

UNLABELLED: Working memory deficits are a cardinal feature of the pathophysiology of schizophrenia. Lesion studies and functional blood flow-dependent imaging methods with coarse temporal resolution, such as PET and functional MRI (fMRI), tend to paint a fairly static picture of the cortical regions involved. In contrast, functional transcranial Doppler sonography (fTCD) provides a high temporal resolution. Truly simultaneous fTCD-fMRI is not yet possible for technical reasons, but H(2)(15)O PET and fTCD can be used really simultaneously. However, this combination has not yet been used for cognitive activations in schizophrenia. We therefore investigated the extent to which there are both spatial (PET) and temporal changes (fTCD) in the activation patterns of schizophrenic patients. METHODS: Eleven clinically stable chronic schizophrenic, right-handed patients and 10 healthy, right-handed control subjects, matched for age, sex, education, and intelligence quotient, participated in the study. We selected stable chronic schizophrenic patients who could perform a working memory task (N-back task) as well as healthy volunteers to exclude the possibility of imaged artifacts due to poor performance. All subjects were examined with a truly simultaneous fTCD-H(2)(15)O PET combination under cognitive activation. RESULTS: Schizophrenic patients activate a significantly larger cortical volume for adequate task performance (P < 0.05), but with a significantly lower blood flow increase in this volume (P < 0.01), than do control subjects. Furthermore, they cannot significantly increase blood flow velocity during the time course of cognitive activation as control subjects do. There were only significant correlations between neuropsychologic performance and imaging parameters (fTCD changes, PET blood flow changes) in control subjects (all r >or= /0.65/; P < 0.05), but no significant correlations in schizophrenics (all r < /0.3/; P > 0.4). CONCLUSION: We demonstrated that schizophrenic patients exhibit qualitative differences in the spatial and temporal resolution of cognitive processing. All facts could be interpreted as a sign of alternative, less efficient problem-solving strategies in schizophrenia that lead to the working memory deficits observed during the further course of this disease. Truly simultaneous fTCD-PET can be used in neuroscience to add fundamental new information on spatial and temporal cognitive activation behavior to understand the true physiologic nature of the disease-specific differences of mental illnesses that are seen as disorders of the mind arising in the brain.


Assuntos
Cognição , Esquizofrenia/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Ultrassonografia Doppler Transcraniana , Adulto , Circulação Cerebrovascular , Feminino , Humanos , Masculino , Esquizofrenia/fisiopatologia
14.
Ultrasound Med Biol ; 38(6): 989-96, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22502885

RESUMO

The neurovascular coupling describes a vasoregulative principle of the brain that adapts local cerebral blood flow in accordance with the underlying neuronal activity. It is the basis of modern indirect brain imaging techniques. Because of its wide availability and high tolerability the functional transcranial Doppler has been often used to assess brain function in clinical conditions. In the present paper we will give an overview of the current understanding of the coupling, explain basic principles of the Doppler technique and summarize relevant findings of functional Doppler tests in the different vascular territories of the brain. Finally, the concept of a combined functional electroencephalogram and transcranial Doppler technique will be outlined, which allows simultaneous investigation of the neuronal and vascular responses of neurovascular coupling.


Assuntos
Circulação Cerebrovascular/fisiologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Eletroencefalografia , Ultrassonografia Doppler Transcraniana/métodos , Humanos
15.
J Neurotrauma ; 26(5): 651-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19281414

RESUMO

The purpose of cerebral autoregulation is to keep cerebral blood flow constant during variations of cerebral perfusion pressure (CPP). Recently, the autoregulatory response was reported to be greater during arterial blood pressure (ABP) increase than during decrease following repeated induced changes in ABP in 14 brain-injured subjects. The goal of this study was to further investigate the asymmetry of autoregulation during spontaneous increases and decreases of CPP in a larger group of brain injury patients. Data recordings (N=727) of CPP and cerebral blood flow velocity (CBFV) in 210 subjects with traumatic brain injury (TBI) were studied. Autoregulation was assessed using moving correlation indices (Mx) between CPP and CBFV. Periods of increasing and decreasing CPP were separately correlated to corresponding CBFV in order to assess autoregulatory responses to upward (upMx) and downward (downMx) changes of CPP. These correlation indices range from -1 to +1; negative or zero values indicate intact autoregulation, whereas positive values indicate impaired autoregulation. Only data with defined strong CPP variations were evaluated. Strong CPP variations were found in 84 recordings of 53 patients. On average (+/-SD) upMx was significantly lower than downMx (0.05+/-0.49 versus 0.14+/-0.54; p < 0.005). Despite this difference, upMx and downMx were strongly correlated with each other (R=0.82; p < 0.001). In conclusion, the autoregulatory response was significantly greater during increase than during decrease in CPP. The results may indicate non-linear behavior of cerebral autoregulation.


Assuntos
Pressão Sanguínea/fisiologia , Circulação Cerebrovascular/fisiologia , Homeostase/fisiologia , Adulto , Lesões Encefálicas/fisiopatologia , Coleta de Dados , Feminino , Humanos , Pressão Intracraniana/fisiologia , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Perfusão , Ultrassonografia Doppler Transcraniana
16.
Eur J Ultrasound ; 16(1-2): 37-45, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12470849

RESUMO

BACKGROUND AND PURPOSE: Until now the assessment of intracranial pressure (ICP) requires invasive methods. A previously introduced mathematical model allowed the non-invasive estimation of ICP (nICP) from arterial blood pressure (ABP) and blood flow velocity (FV). In various studies we have investigated the accuracy of this method and possible clinical applications. METHODS AND RESULTS: Selected hemodynamic parameters, calculated from the cerebral blood FV and the ABP curves, were used to express the relationship between ABP input and ICP output by linear transformation rules. In several clinical studies the accuracy and possible benefits of this method of non-invasive ICP (nICP) assessment were investigated. ASSESSMENT OF ICP PLATEAU WAVES: In 17 severely head injured patients we verified this model by comparison of nICP and measured ICP during generation of plateau waves, recorded in seven of these patients. In all simulations plateau elevations of ICP were well replicated. The correlation coefficient between increase of nICP and real ICP was R=0.98; P<0.001. LUMBAR INFUSION TESTS: Twenty one hydrocephalic patients were studied. Parallel increases in real ICP and nICP during lumbar infusion tests were evidently visible. Resistance of cerebrospinal fluid outflow (Rcsf) was computed using nICP and compared with Rcsf computed from real ICP. The mean error between real and non-invasive Rcsf was 4.1+/-2.2 mmHg min/ml. CEREBRAL AUTOREGULATION: One hundred and forty five patients were studied after severe head injuries. The state of autoregulation was assessed by moving correlation of cerebral perfusion pressure (CPP=ABP-ICP) and FV (Mx index). nICP instead of ICP was used to continuously estimate the state of autoregulation and to dynamically adapt the nICP procedure to this state. A median error between ICP and nICP of 6.0 mmHg was observed. Directly and non-invasively assessed Mx indices correlated highly significantly (R=0.9; P<0.001). CONCLUSIONS: The results demonstrate that the nICP assessment model constitutes a reliable method to monitor ICP and may therefore provide various useful clinical applications.


Assuntos
Circulação Cerebrovascular , Traumatismos Craniocerebrais/fisiopatologia , Hidrocefalia/fisiopatologia , Pressão Intracraniana , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Encéfalo/fisiopatologia , Traumatismos Craniocerebrais/diagnóstico por imagem , Hemodinâmica , Homeostase , Humanos , Hidrocefalia/diagnóstico por imagem , Modelos Teóricos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Ultrassonografia Doppler Transcraniana
17.
Psychother Psychosom Med Psychol ; 54(3-4): 165-72, 2004.
Artigo em Alemão | MEDLINE | ID: mdl-15037981

RESUMO

Given the clinical and scientific relevance of dissociative experiences our study aimed to assess the psychometric properties of a short version of the German Dissociative Experience Scale (called FDS-20) as well as its ability to measure changes in dissociation. In a large sample (N = 1289) the FDS- 20 showed good internal consistency. A factor analysis indicated that the scale measures one single factor reflecting the general degree of dissociative psychopathology. Between-group-comparisons suggested a good discriminant validity between high and low dissociators; however, due to high standard deviations the FDS-20 is not well suited for an individual diagnosis and therefore, it should be used as a screening device. Low effect sizes (d < 0,3) between scores at the beginning and the end of inpatient treatment as well as low micro -indices pointed to a temporal stable construct and a trait scale, respectively. Alternatively to group comparisons, individual parameters of treatment success (statistical and clinical significance) were calculated. They proved to be more appropriate in measuring changes in dissociation.


Assuntos
Transtornos Dissociativos/diagnóstico , Transtornos Dissociativos/psicologia , Escalas de Graduação Psiquiátrica , Adolescente , Adulto , Idoso , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes
18.
Cerebrovasc Dis ; 13(1): 57-63, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11810012

RESUMO

In this study, we analyzed the relationship between serum C-reactive protein (CRP) and the intima to media thickness (IMT) of the common carotid artery in 411 consecutive neurological inpatients (215 males, mean age 64.1 years). The CRP concentration was determined within 12 h and patients were subdivided according to the CRP level. Patients with an elevated CRP (n = 149) showed a significantly larger IMT [1.05 mm (95% confidence interval (CI) 1.02-1.09) vs. 0.92 mm (95% CI 0.89-0.94)]. Multivariate linear regression analysis revealed that an elevated CRP level, age, pack-years of smoking, body mass index, incidence of diabetes mellitus and ischemic stroke were independently associated with an increased IMT (p < 0.05).


Assuntos
Proteína C-Reativa/metabolismo , Doenças das Artérias Carótidas/epidemiologia , Doenças das Artérias Carótidas/patologia , Artéria Carótida Primitiva/patologia , Idoso , Arterite/diagnóstico por imagem , Arterite/epidemiologia , Arterite/patologia , Doenças das Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Túnica Íntima/patologia , Túnica Média/patologia , Ultrassonografia Doppler Dupla
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