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BackgroundThe coronary calcium score (CAC) measured on chest computerized tomography is a risk marker of cardiac events and mortality. We compared CAC scores in two multiethnic groups without symptomatic coronary artery disease: subjects in the chronic phase after stroke or transient ischemic attack and at least one symptomatic stenosis ≥50% in the carotid or vertebrobasilar territories (Groupathero) and a control group (Groupcontrol).MethodsIn this cross-sectional study, Groupathero included two subgroups: GroupExtraorIntra, with stenoses in either cervical or intracranial arteries, and GroupExtra&Intra, with stenoses in at least one cervical and one intracranial artery. Groupcontrol had no history of prior stroke/transient ischemic attacks and no stenoses ≥50% in cervical or intracranial arteries. Age and sex were comparable in all groups. Frequencies of CAC ≥100 and CAC > 0 were compared between Groupathero and Groupcontrol, as well as between GroupExtraorIntr, GroupExtra&Intra, and Groupcontrol, with bivariate logistic regressions. Multivariate analyses were also performed.ResultsA total of 120 patients were included: 80 in Groupathero and 40 in Groupcontrol. CAC >0 was significantly more frequent in Groupathero (85%) than Groupcontrol (OR, 4.19; 1.74–10.07; p = 0.001). Rates of CAC ≥100 were not significantly different between Groupathero and Groupcontrol but were significantly greater in GroupExtra&Intra (n = 13) when compared to Groupcontrol (OR 4.67; 1.21–18.04; p = 0.025). In multivariate-adjusted analyses, “Groupathero” and “GroupExtra&Intra” were significantly associated with CAC.ConclusionThe frequency of coronary calcification was higher in subjects with stroke caused by large-artery atherosclerosis than in controls.

A toxina botulínica (TB) é uma neurotoxina que pode ser usada em diversos tratamentos na Odontologia, como, por exemplo, na aplicação em pacientes com paralisia periférica de Bell (PPB). Nesses casos, a musculatura facial do lado contralateral à paralisia pode evoluir com espasticidade, sendo necessário o relaxamento dos músculos envolvidos para a harmonização orofacial do paciente. Objetivo: Demonstrar a harmonização orofacial em paciente com PPB por meio da aplicação de TB tipo A. Relato de caso: Paciente, 55 anos, homem, apresentando paralisia hemifacial, recebeu aplicação de TB com finalidade de reequilíbrio do tônus muscular, a fim de reduzir a espasticidade dos músculos orbicular dos olhos, levantador do lábio superior e asa do nariz, risório e orbicular dos lábios, no lado oposto ao da paralisia. Conclusão: No paciente do atual relato de caso, o uso de toxina botulínica proporcionou um resultado de harmonização orofacial e, segundo o próprio paciente, houve influência positiva também na autoestima e convívio social.

To analyze the influences of mild and severe intracranial hypertension on cerebral autoregulation (CA).Duroc piglets were monitored with an intracranial pressure (ICP) catheter. Intracranial hypertension was induced via infusion of 4 or 7 ml of saline solution by a bladder catheter that was inserted into the parietal lobe. The static cerebral autoregulation (sCA) index was evaluated via cerebral blood flow velocities (CBFv). Piglets with ICPs ≤ 25 and25 mmHg were considered as group 1 and 2, respectively. Continuous variables were evaluated using the Kolmogorov-Smirnov goodness-of-fit test. The main parameters were collected before and after ICH induction and compared using two-factor mixed-design ANOVAs with the factor of experimental group (mild and severe ICH).In group 1 (ICP ≤ 25 mmHg), there were significant differences in sCA (We conclude that intracranial hypertension may have a direct effect on sCA.

This study aimed to investigate the accuracy of TCS combined with the Sniffin' sticks olfactory test (SST-16) for differentiation between idiopathic PD patients and healthy controls compared to that ofsup99 m/supTc-TRODAT-1 SPECT (TRODAT).A cross-sectional study included PD patients diagnosed in accordance with United Kingdom PD Society Brain Bank criteria and a control group of age and sex- matched healthy subjects. All patients were examined by a movement disorder specialist and underwent brain SPECT using TRODAT, TCS examination and SST-16 test. Receiver Operating Characteristic (ROC) curves were used to calculate cut-off points for TCS, striatal TRODAT binding potentials and SST-16. The area under the ROC curve determined the diagnostic accuracy of the method.Twenty patients with PD (13 males and 7 females) and nine healthy subjects were included. Median age of PD onset was 56.5 years with median disease duration of 5 years. A larger substantia nigra (SN) echogenic area was observed in the PD group (p = 0.013). SN echogenic area cut-off point of 0.22 cmsup2/supwas obtained from a ROC curve for PD diagnosis. Considering this cut-off point, TCS diagnostic accuracy was estimated at 79.2% for PD diagnosis. The cut-off value of 0.90 for striatal TRODAT binding was associated with 99% diagnostic accuracy for the diagnosis of PD. SST-16 values equal or less than 9 points showed an 85.8% diagnostic accuracy for PD diagnosis. Combination of both SST-16 and TCS improved the diagnostic accuracy to 95% for PD diagnosis.Combined SST-16 and TCS assessment was indicated as accurate for distinguishing PD patients from healthy controls. The diagnostic accuracy of TCS combined with SST-16 for differentiation between idiopathic PD patients and healthy controls is similar to that of SPECT TRODAT.

Purpose: To determine the normal optical nerve sheath (ONS) diameter ultrasonography (ONSUS) and evaluate the possible effects of drugs on ONS diameter during anesthetic induction in healthy pigs. Methods: Healthy piglets were divided into three groups: a control group, that received xylazine and ketamine (X/K); other that received xylazine, ketamine and propofol (X/K/P); and a third group that received xylazine, ketamine, and thiopental (X/K/T). The sheath diameter was assessed by ultrasonography calculating the average of three measurements of each eye from the left and right sides. Results: 118 animals were anesthetized (49 X/K 33 X/K/P and 39 X/K/T). Mean ONS sizes on both sides in each group were 0.394 ± 0.048 (X/K), 0.407 ± 0.029 (X/K/P) and 0.378 ± 0.042 cm (X/K/T) (medians of 0.400, 0.405 and 0.389, respectively). The ONS diameter varied from 0.287–0.512 cm (mean of 0.302 ± 0.039 cm). For group X/K, the mean diameter was 0.394 ± 0.048 cm. Significant differences in ONS sizes between the groups P and T (X/K/P > X/K/T, p = 0.003) were found. No statistically significant differences were detected when other groups were compared (X/K = X/K/P, p = 0.302; X/K = X/K/T, p = 0.294). Conclusions: Sedation with thiopental lead to significative ONS diameter reduction in comparison with propofol. ONSUS may be useful to evaluate responses to thiopental administration.

Objective To evaluate the interobserver reliability of a new scale created for quantitatively assessing brain swelling in traumatic brain injury (TBI) patients using the computed tomography (CT) findings in three levels. Methods Computed tomography scans of severe head injury patients were randomly selected from a tertiary hospital image database and evaluated by independent groups of neurosurgeons, neurosurgery residents, radiologists, and intensivists from the same hospital. Each specialist assessed the tomographic findings, applying zero to six points in a new scale. The Kappa coefficient was calculated to assess interobserver agreement. Results The highest reliability coefficient was obtained by the neurosurgeons group (0.791; 95% confidence interval [CI]: 0.975–0.607; p Conclusion The proposed scale showed good reliability among neurosurgeons, and moderate overall reliability. This tomographic classification might be useful to better assist severe TBI victims, allowing to identify the worsening or amelioration of brain swelling, which should be further investigated. The scale seems to be feasible, even in low income countries, where the cost of intracranial pressure (ICP) monitoring is higher than that of CTs.

Objective: This research evaluated the hemodynamic conditions before and after the transcranial photobiomodulation therapy (PBMT) and investigated neurocognitive changes before and after treatment. Background: Traumatic brain injury (TBI) is the major cause of morbidity and mortality among individuals 21–60 years old and causes ∼500,000 people to be hospitalized in Brazil annually. Some survivors develop an irreversible decrease in neurological function, and the mortality rate is as high as 70% in severe cases. PBMT is an alternative to treat secondary injuries due to TBI. Methods: This multidisciplinary clinical study was carried out on 10 chronic adult patients with severe TBI, who were treated with PBMT with an optical device containing 13 sets of 4 light emitting diodes, and underwent hemodynamic transcranial Doppler and neuropsychological evaluation at three different times: pre-PBMT, post-PBMT (after a week), and late-PBMT, which occurred 3 months after the last session. The patients received PBMTs three times a week, for 6 weeks. PBMTs were performed for 18 sessions for 6 weeks and 30 min per session. Results: The results found an alteration in the cerebral blood flow (CBF) as well as a consequent increase of the cerebral oxygenation that helped to improve the cerebral function. Conclusions: The PBMT contributed to increased CBF, evidenced mainly by the increased left peak systolic velocity, which consequently increased the hemodynamic response after the PBMT and impacts on the peripheral cerebral perfusion contributing to improved cerebral function.

Sickle-cell disease (SCD) is the most common cause of ischemic stroke in children and it happens in about 11% of patients between the age of 2 and 20 years old. About 7% of the world population is affected by hemoglobin disorders, mostly sickle cell anemia. SCD has a high prevalence in the population of African offspring and it is a public health problem in Brazil that affects more than 30,000 million people. Prevention of primary stroke might be feasible with a way to identify children at greatest risk. Transcranial Doppler Ultrasonography (TCD) to SCD patients can be a valuable service that results in a significant decrease of first stroke rates. In this work, we present a review about TCD as an effective strategy to detect children with SCD who are at risk for stroke.

Introdução: Os principais objetivos do tratamento das metástases cerebrais (MC) são no auxílio do controle da doença no encéfalo e a melhora da qualidade de vida dos pacientes. A cirurgia convencional tem um importante papel no tratamento das MCs e os métodos de monitoração intraoperatória podem auxiliar na obtenção de resultados cirúrgicos melhores. Objetivos: Avaliar a influência da ultrassonografia encefálica durante cirurgia para ressecção de MC no índice de Karnofsky e no grau de ressecção do tumor. Métodos: Neste estudo prospectivo controlado e não randomizado, doentes com indicação de tratamento cirúrgico de MCs foram incluídos. A ultrassonografia intraoperatória (USIO) foi realizada por um neurossonologista. O índice de Karnofsky foi avaliado por equipe multidisciplinar de oncologia; o grau de dificuldade para ressecção cirúrgica do tumor foi avaliado pelo cirurgião e o volume tumoral foi avaliado pelo neurorradiologista por meio da RM realizada no pré e pós-operatório. Resultados: Dos 78 doentes, 40 homens e 38 mulheres com idade média de 53 anos, 35 foram submetidos a tratamento cirúrgico com auxílio da USIO. Não houve diferença estatística no KPS e volume tumoral pré- operatório entre os grupos. O KPS pós-operatório no grupo da USIO foi de 80 e no grupo-controle de 70 (p=0,045). Considerando-se a melhora do KPS no pós-operatório, a quantidade de doentes tiveram melhora do KPS foi superior no grupo da USIO (p=0,036) destacando-se os seguintes subgrupos: tumores com grau de dificuldade de ressecção =70, o número de doentes com volume de tumor residual inferior a 10% em relação ao volume pré-operatório foi superior no grupo da USIO (p=0,032 e OR de 3,8). Conclusão: Os achados deste estudo sugerem que a USIO encefálica pode influenciar na melhora do índice de Karnofsky e na redução do volume de tumor residual. Object: The goals of treating a cerebral metastasis (CM) are to achieve local control of the disease and to improve patient quality of life. The aim of this study was to analyse the effect of using conventional surgery supported by intra-operative ultrasound (IOUS) to approach a CM. To perform this analysis, we determined Karnofsky post-operative scores (KPS) and tumour resection grades. Methods: Patients with CM who were eligible to undergo a surgical approach were included in this study. Surgical treatment was either supported or not supported by IOUS. A neural oncology team determined the pre- and post-operative KPS. A radiologist examined the tumour volume using pre- and post-operative magnetic resonance imaging. Before the surgery, the surgeon determined whether it was possible to perform a total CM resection. Results: A total of 78 patients with CM diagnosis were treated using a surgical approach (35 with and 43 without IOUS). The post-operative median KPS was higher in the IOUS group (80 versus 70, p=0.045). Within the IOUS group, KPS evolution was superior (p=0.036), especially in the following CM subgroups: a difficulty of tumour resection ranking score=70, the residual tumour volume was categorized as =10%, and 62% of patients had

Background: Coronary calcium score (CAC) is a marker of coronary atherosclerosis. We compared CAC scores in patients with ischemic stroke (IS) caused by large-artery atherosclerosis (Groupathero) to a control group (Groupcontrol), in multiethnic subjects without history of symptomatic coronary artery disease (CAD). Methods: In this cross-sectional study, subjects in Groupathero (n=80) had at least one symptomatic stenosis ≥ 50% in the carotid or vertebrobasilar territories. Groupathero included two subgroups: stenosis in either cervical or intracranial arteries (GroupExtraorIntra), and in at least one cervical and one intracranial artery (GroupExtra&Intra). Subjects in Groupcontrol (n=40) had no history of stroke or stenosis ≥ 50% in cervical or intracranial arteries. Frequencies of CAC ≥ 100 and CAC > 0 were compared between the groups and subgroups by bivariate logistic regressions. Multivariate analyses were also performed. Results: Rates of CAC ≥ 100 were not significantly different between Groupathero and Groupcontrol but were significantly greater in GroupExtraI 1.21-18.04; p = 0.025). CAC > 0 was significantly more frequent in Groupathero (85%) than Groupcontrol (OR, 4.19; 1.74-10.07; p = 0,001). In multivariate analyses, “Groupathero” and “GroupExtra&Intra” was significantly and independently associated with CAC. Conclusions: The frequency of coronary calcification was higher in subjects with atherothrombotic stroke without symptoms of coronary disease than in controls with similar vascular risk factors. In patients with stroke, the burden of subclinical CAD was significantly higher in those with cervical and intracranial atherosclerosis.

Background: Invasive monitoring of intracranial pressure (ICP) is currently the gold standard method for the safe diagnosis and treatment of intracranial hypertension (ICHy), but it is subject to hemorrhage, infection and malfunction. Ultrasound of the optic nerve sheath diameter (ONSD) has been applied as a non-invasive alternative that is cost effective and available at the bedside. However, ONSD time-lapse behavior in a set of ICHy and its relief by means of whether saline infusion or surgery is still unknown. The objective of this study was to correlate intracranial pressure and ultrasonography of the optic nerve sheath in an experimental animal model of ICHy, and the interval needed to ONSD to return to its baseline levels.Methods: An experimental study was conducted on 30 male and female pigs weighing about 20 kg. The diameter of the optic nerve sheath was evaluated by ultrasound at different measures of ICP given by intraventricular catheter and intracranial balloon inflation, saline infusion and balloon deflation. Laboratory and hemodynamic data were collected from the animals. ICP and ONSD values were correlated at each time point of the study.Results: All the variables obtained by ONSD ultrasonography as left optic nerve, right optic nerve and average of optic nerve sheath (AON) diameter were statistically significant to estimate ICP value. ONSD values changed immediately at balloon inflation, with a delay of 30 minutes average to return to baseline levels after balloon deflation (p = 0.016). No statistical significance was observed in ICP and ONSD values with hypertonic saline infusion. Correlation between ICP and ONSD was linear and can be estimated using the formula: -80.5 + 238.2 x AON, in this swine model. Conclusion: In the present study, ultrasound of optic nerve sheath diameter disclosed linear correlation with ICP, although a short delay in returning to its baseline levels may be observed in the case of sudden intracranial hypertension relief.

Objective Despite advances in systemic therapy and radiotherapy (RT), neurosurgical resection (NSR) remains a mainstay of the treatment of brain metastases (BMs). Although it is unequivocal in instances of diagnostic doubt, radioresistance, and risk of death due to neurologic causes, NSR may be controversial in other situations. Many aspects related to NSR have not yet been well established, and the primary prognostic indices were proposed only in the last decade. This study evaluates the survival and the morbidity, causes of death, prognostic factors, and the impact of RT in patients with BMs treated by NSR in the current era. Methods A total of 200 patients with BMs who were treated by NSR were evaluated sequentially and followed prospectively. We used logistic regression and Cox regression models to identify independent factors associated with mortality at 4 weeks and at 1 year, respectively. Clinical features, morbidity, recurrence, and causes of death were also studied. Results Lung cancer was the most prevalent cancer (36.5%); the median Karnofsky Performance Status (KPS) score was 60. Total resection was achieved in 89%, and adjuvant RT was applied in 63% of the cases. The rates of surgical mortality, morbidity, and mortality at 4 weeks were 1.5%, 17%, and 7.5%, respectively. Systemic infections were the leading cause of death in 62.5% of the cases. The median survival was 5 months, and 34.5% of patients lived > 1 year. The postoperative KPS (KPSpo) score remained unchanged or improved in 94.5% of the cases. In the multivariate analysis, a KPSpo score ≥ 80 and the application of adjuvant RT were associated with a lower risk of death at 12 weeks and at 1 year. Interestingly, the variables of primary tumor site, number of BMs, and presence of carcinomatous meningitis were not significant. Conclusion Morbidity and mortality were high, a third of the patients lived > 1 year, and the KPS score improved or remained unchanged in most cases. Prognostic indices and health conditions were important predictive factors, but the KPSpo score and adjuvant RT were independent variables for survival at 12 weeks and at 1 year. Therefore, new studies are needed to assess the influence of new therapies and specific molecular profiles.

The advent of intraoperative ultrasonography (USG) has allowed identification of craniocervical junction (CVJ) anatomy and cerebrospinal fluid dynamics and CVJ structures with real-time images. It is possible to use intraoperative USG in patients with Chiari malformation type I as a method for selection of candidates for posterior fossa decompression with bone removal alone. This chapter describes the authors’ experience using intraoperative USG.

We aimed to assess cerebral autoregulation (CA) and neurovascular coupling (NVC) in stroke patients of differing severity comparing responses to healthy controls and explore the association between CA and NVC with functional outcome. Patients admitted with middle cerebral artery (MCA) stroke and healthy controls were recruited. Stroke severity was defined by the National Institutes of Health Stroke Scale (NIHSS) scores: ≤4 mild, 5–15 moderate and ≥16 severe. Transcranial Doppler ultrasound and Finometer recorded MCA cerebral blood flow velocity (CBFv) and blood pressure, respectively, over 5 min baseline and 1 min passive movement of the elbow to calculate the autoregulation index (ARI) and CBFv amplitude responses to movement. All participants were followed up for three months. A total of 87 participants enrolled in the study, including 15 mild, 27 moderate and 13 severe stroke patients, and 32 control subjects. ARI was lower in the affected hemisphere (AH) of moderate and severe stroke groups. Decreased NVC was seen bilaterally in all stroke groups. CA and NVC correlated with stroke severity and functional outcome. CBFv regulation is significantly impaired in acute stroke, and further compromised with increasing stroke severity. Preserved CA and NVC in the acute period were associated with improved three-month functional outcome.

Introduction: One of the possible mechanisms by which the new coronavirus (SARS-Cov2) could induce brain damage is the impairment of cerebrovascular hemodynamics (CVH) and intracranial compliance (ICC) due to the elevation of intracranial pressure (ICP). The main objective of this study was to assess the presence of CVH and ICC alterations in patients with COVID-19 and evaluate their association with short-term clinical outcomes. Methods: Fifty consecutive critically ill COVID-19 patients were studied with transcranial Doppler (TCD) and non-invasive monitoring of ICC. Subjects were included upon ICU admission, CVH was evaluated using mean flow velocities in the middle cerebral arteries (mCBFV), pulsatility index (PI), and estimated cerebral perfusion pressure (eCPP), while ICC was assessed by using the P2/P1 ratio of the non-invasive ICP curve. A CVH/ICC score was computed using all these variables. The primary composite outcome was unsuccessful in weaning from respiratory support or death on day 7 (defined as UO). Results: At the first assessment (n = 50), only the P2/P1 ratio (median 1.20 [IQRs 1.00–1.28] vs. 1.00 [0.88–1.16], p = 0.03) and eICP (14 [11–25] vs. 11 [7–15] mmHg, p = 0.01) were significantly higher among patients with an unfavorable outcome (UO) than others. Patients with UO had a significantly higher CVH/ICC score (9 [8–12] vs. 6 [5–7], p &lt, 0.001) than those with a favorable outcome, the area under the receiver operating curve (AUROC) for CVH/ICC score to predict UO was 0.86 (95% CIs 0.75–0.97), a score &gt, 8.5 had 63 (46–77)% sensitivity and 87 (62–97)% specificity to predict UO. For those patients undergoing a second assessment (n = 29), after a median of 11 (5–31) days, all measured variables were similar between the two time-points. No differences in the measured variables between ICU non-survivors (n = 30) and survivors were observed. Conclusions: ICC impairment and CVH disturbances are often present in COVID-19 severe illness and could accurately predict an early poor outcome.

The goals of treating a cerebral metastasis (CM) are to achieve local control of the disease and to improve patient quality of life. The aim of this study was to analyze the effect of conventional surgery supported by intraoperative ultrasound (IOUS) to approach a CM. To perform this analysis, we determined the postoperative Karnofsky Performance Status Scale (KPS) scores and tumor resection grades.Patients with a CM diagnosis were included in this study. Surgical treatment was either supported or not by IOUS. Pre- and postoperative KPS scores were determined by the oncology team, and cerebral tumor volume was estimated through pre- and postoperative magnetic resonance imaging. The surgical team determined whether it was possible to perform a total CM resection.There were 78 patients treated using surgical management (35 with and 43 without IOUS). In the IOUS group, the postoperative KPS scores were higher (80 vs. 70, respectively; P = 0.045) and the KPS evolution was superior (P = 0.036), especially in the following subgroups: difficulty of tumor resection ranking score4 (P = 0.037), tumor in an eloquent area (P = 0.043), tumor not associated with vessels or nerves (P = 0.007), and solitary lesions (P = 0.038). The residual tumor volume was lower in the IOUS group (9.5% and 1.6 mmIOUS may improve postoperative KPS scores and decrease residual tumor volumes in CM surgeries. These findings should be confirmed in future studies.

Objective Intra-aortic balloon pump (IABP) is commonly used as mechanical support after cardiac surgery or cardiac shock. Although its benefits for cardiac function have been well documented, its effects on cerebral circulation are still controversial. We hypothesized that transfer function analysis (TFA) and continuous estimates of dynamic cerebral autoregulation (CA) provide consistent results in the assessment of cerebral autoregulation in patients with IABP. Approach Continuous recordings of blood pressure (BP, intra-arterial line), end-tidal CO2, heart rate and cerebral blood flow velocity (CBFV, transcranial Doppler) were obtained (i) 5 min with IABP ratio 1:3, (ii) 5 min, starting 1 min with the IABP-ON, and continuing for another 4 min without pump assistance (IABP-OFF). Autoregulation index (ARI) was estimated from the CBFV response to a step change in BP derived by TFA and as a function of time using an autoregressive moving-average model during removal of the device (ARI t ). Critical closing pressure and resistance area-product were also obtained. Main results ARI with IABP-ON (4.3 ± 1.2) were not different from corresponding values at IABP-OFF (4.7 ± 1.4, p = 0.42). Removal of the balloon had no effect on ARI t , CBFV, BP, cerebral critical closing pressure or resistance area-product. Significance IABP does not disturb cerebral hemodynamics. TFA and continuous estimates of dynamic CA can be used to assess cerebral hemodynamics in patients with IABP. These findings have important implications for the design of studies of critically ill patients requiring the use of different invasive support devices.

Introduction Retrograde ventriculosinus shunt (RVSS) is a useful option in the daily routine of neurosurgeons dealing with hydrodynamics. The objective of this manuscript is to review the main data about RVSS. Methods We performed a critical review. The keywords used were hydrocephalus, shunt, venous sinus, ventriculosinus shunt, retrograde ventriculosinus shunt, and sagittal sinus. The search was performed in the Medline (Pubmed) and EMBASE databases. Results Van Canneyt et al (2008) and Pinto et al (2016) performed experimental studies confirming the effectiveness of RVSS. El Shafei et al (1985, 1987, 2001) authors reported several cases treated with efficacy and few complications. Oliveira et al (2015, 2016) compared RVSS and ventriculoperitoneal shunt (VPS) in the treatment of hydrocephalus after myelomeningocele repair in infants, with similar functional results. Oliveira et al (2015, 2016) also described the applicability of RVSS in situations when VPS is not feasible, or when the peritoneum is not useful. Discussion Retrograde ventriculosinus shunt is a safe and more physiological option, which requires the use of less prosthetic material. It is feasible and applicable. Especially in children, it generates a normotensive state after shunting, allowing centrifugal head growth, once there is no intracranial hypotension due to overdrainage, which may reflect in long-term better psychomotor development. Conclusions The surgical technique of RVSS is feasible. The clinical results are comparable with those of the VPS.

Background: The intra-aortic balloon pump (IABP) is often used in high-risk patients undergoing cardiac surgery to improve coronary perfusion and decrease afterload. The effects of the IABP on cerebral hemodynamics are unknown. We therefore assessed the effect of the IABP on cerebral hemodynamics and on neurological complications in patients undergoing cardiac surgery who were randomized to receive or not receive preoperative IABP in the ‘Intra-aortic Balloon Counterpulsation in Patients Undergoing Cardiac Surgery’ (IABCS) trial. Methods: This is a prospectively planned analysis of the previously published IABCS trial. Patients undergoing elective coronary artery bypass surgery with ventricular ejection fraction ≤ 40% or EuroSCORE ≥ 6 received preoperative IABP (n = 90) or no IABP (n = 91). Cerebral blood flow velocity (CBFV) of the middle cerebral artery through transcranial Doppler and blood pressure through Finometer or intra-arterial line were recorded preoperatively (T1) and 24 h (T2) and 7 days after surgery (T3) in patients with preoperative IABP (n = 34) and without IABP (n = 33). Cerebral autoregulation was assessed by the autoregulation index that was estimated from the CBFV response to a step change in blood pressure derived by transfer function analysis. Delirium, stroke and cognitive decline 6 months after surgery were recorded. Results: There were no differences between the IABP and control patients in the autoregulation index (T1: 5.5 ± 1.9 vs. 5.7 ± 1.7; T2: 4.0 ± 1.9 vs. 4.1 ± 1.6; T3: 5.7 ± 2.0 vs. 5.7 ± 1.6, p = 0.97) or CBFV (T1: 57.3 ± 19.4 vs. 59.3 ± 11.8; T2: 74.0 ± 21.6 vs. 74.7 ± 17.5; T3: 71.1 ± 21.3 vs. 68.1 ± 15.1 cm/s; p = 0.952) at all time points. Groups were not different regarding postoperative rates of delirium (26.5% vs. 24.2%, p = 0.83), stroke (3.0% vs. 2.9%, p = 1.00) or cognitive decline through analysis of the Mini-Mental State Examination (16.7% vs. 40.7%; p = 0.07) and Montreal Cognitive Assessment (79.16% vs. 81.5%; p = 1.00). Conclusions: The preoperative use of the IABP in high-risk patients undergoing cardiac surgery did not affect cerebral hemodynamics and was not associated with a higher incidence of neurological complications. Trial registrationhttp://www.clinicaltrials.gov (NCT02143544)., SCOPUS: ar.j, info:eu-repo/semantics/published

Substantia nigra (SN) hyperechogenicity has been proved to be a characteristic finding for idiopathic Parkinson's disease (PD), occurring in more than 90% of the patients. This echofeature is owed to increased amounts of iron in the SN region and reflects a functional impairment of the nigrostriatal dopaminergic system. In a prospective blinded study in which a group of patients with early mild signs and symptoms of unclear Parkinsonism were followed until a definite clinical diagnosis of PD, the hyperechogenicity of the SN was demonstrated to be highly predictive of a final diagnosis of PD. For the diagnosis of PD in individuals with early motor symptoms, both the sensitivity and positive predictive value of SN hyperechogenicity were higher than 90% and both the specificity and negative predictive value were higher than 80%. For early differential diagnosis between PD and atypical Parkinsonian syndromes, the sensitivity and positive predictive value of SN hyperechogenicity were higher than 90%, and both the specificity and negative predictive value were higher than 80%. The diagnostic specificity is increased if combining the TCS findings of SN, lenticular nucleus and third ventricle. In asymptomatic adult subjects, SN hyperechogenicity, at least unilaterally, indicates a subclinical functional insufficiency of the nigrostriatal dopaminergic system. Recent papers revealed that SN hyperechogenicity might suggest preclinical PD. Reduced echogenicity of midbrain raphe indicates increased risk of depression in PD patients. Caudate nucleus hyperechogenicity has been associated with drug-induced psychosis, and frontal horn dilatation >20 mm with dementia. Transcranial brain sonography can be a valuable tool for managing patients with Parkinsonian signs and symptoms.

OBJECTIVEThe present study was designed to answer several concerns disclosed by systematic reviews indicating no evidence to support the use of computed tomography angiography (CTA) in the diagnosis of brain death (BD). Therefore, the aim of this study was to assess the effectiveness of CTA for the diagnosis of BD and to define the optimal tomographic criteria of intracranial circulatory arrest.METHODSA unicenter, prospective, observational case-control study was undertaken. Comatose patients (Glasgow Coma Scale score ≤ 5), even those presenting with the first signs of BD, were included. CTA scanning of arterial and venous vasculature and transcranial Doppler (TCD) were performed. A neurological determination of BD and consequently determination of case (BD group) or control (no-BD group) was conducted. All personnel involved with assessing patients were blinded to further tests results. Accuracy of BD diagnosis determined by using CTA was calculated based on the criteria of bilateral absence of visualization of the internal cerebral veins and the distal middle cerebral arteries, the 4-point score (4PS), and an exclusive criterion of absence of deep brain venous drainage as indicated by the absence of deep venous opacification on CTA, the venous score (VS), which considers only the internal cerebral veins bilaterally.RESULTSA total of 106 patients were enrolled in this study; 52 patients did not have BD, and none of these patients had circulatory arrest observed by CTA or TCD (100% specificity). Of the 54 patients with a clinical diagnosis of BD, 33 met the 4PS (61.1% sensitivity), whereas 47 met the VS (87% sensitivity). The accuracy of CTA was time related, with greater accuracy when scanning was performed less than 12 hours prior to the neurological assessment, reaching 95.5% sensitivity with the VS.CONCLUSIONSCTA can reliably support a diagnosis of BD. The criterion of the absence of deep venous opacification, which can be assessed by use of the VS criteria investigated in this study, can confirm the occurrence of cerebral circulatory arrest.Clinical trial registration no.: 12500913400000068 (clinicaltrials.gov)

Background: There are no studies describing the cerebral hemodynamic patterns that can occur in traumatic brain injury (TBI) patients following decompressive craniectomy (DC). Such data have potentially clinical importance for guiding the treatment. The objective of this study was to investigate the postoperative cerebral hemodynamic patterns, using transcranial Doppler (TCD) ultrasonography, in patients who underwent DC. The relationship between the cerebral circulatory patterns and the patients' outcome was also analyzed. Methods: Nineteen TBI patients with uncontrolled brain swelling were prospectively studied. Cerebral blood circulation was evaluated by TCD ultrasonography. Patients and their cerebral hemispheres were categorized based on TCD-hemodynamic patterns. The data were correlated with neurological status, midline shift on CT scan, and Glasgow outcome scale scores at 6 months after injury. Results: Different cerebral hemodynamic patterns were observed. One patient (5.3%) presented with cerebral oligoemia, 4 patients (21%) with cerebral hyperemia, and 3 patients (15.8%) with cerebral vasospasm. One patient (5.3%) had hyperemia in one cerebral hemisphere and vasospasm in the other hemisphere. Ten patients (52.6%) had nonspecific circulatory pattern. Abnormal TCD-circulatory patterns were found in 9 patients (47.4%). There was no association between TCD-cerebral hemodynamic findings and outcome. Conclusion: There is a wide heterogeneity of postoperative cerebral hemodynamic findings among TBI patients who underwent DC, including hemodynamic heterogeneity between their cerebral hemispheres. DC was proved to be effective for the treatment of cerebral oligoemia. Our data support the concept of heterogeneous nature of the pathophysiology of the TBI and suggest that DC as the sole treatment modality is insufficient.

Background: The role of patent foramen ovale is a field of debate and current publications have increasing controversies about the patients’ management in young undetermined stroke. Work up with echocardiography and transcranial Doppler (TCD) can aid the decision with better anatomical and functional characterization of right-to-left shunt (RLS). Medical and interventional strategy may benefit from this information. Summary: a group of experts from the Latin American participants of the Neurosonology Research Group (NSRG) of World Federation of Neurology created a task force to review literature and describe the better methodology of contrast TCD (c-TCD). All signatories of the present consensus statement have published at least one study on TCD as an author or co-author in an indexed journal. Two meetings were held while the consensus statement was being drafted, during which controversial issues were discussed and voted on by the statement signatories. The statement paper was reviewed and approved by the Executive Committee of the NSRG of the World Federation of Neurology. The main objective of this consensus statement is to establish a standardization of the c-TCD technique and its interpretation, in order to improve the informative quality of the method, resulting in expanding the application of TCD in the clinical setting. These recommendations optimize the comparison of different diagnostic methods and encourage the use of c-TCD for RLS screening and complementary diagnosis in multicenter studies.

OBJECTIVE: To evaluate the findings of magnetic resonance angiography (MRA) and transcranial Doppler ultrasound (TCD) in patients with a clinical diagnosis of vertebrobasilar insufficiency (VBI). METHOD: From our outpatient neurotology clinic, we selected patients (using the criteria proposed by Grad and Baloh) with a clinical diagnosis of VBI. We excluded patients with any definite cause for vestibular symptoms, a noncontrolled metabolic disease or any contraindication to MRA or TCD. The patients in the study group were sex- and age-matched with subjects who did not have vestibular symptoms (control group). Our final group of patients included 24 patients (study, n=12; control, n=12). RESULTS: The MRA results did not demonstrate significant differences in the findings between our study and control groups. TCD demonstrated that the systolic pulse velocity of the right middle cerebral artery, end diastolic velocity of the basilar artery, pulsatility index (PI) of the left middle cerebral artery, PI of the right middle cerebral artery, and PI of the basilar artery were significantly higher in the study group than in the control group, suggesting abnormalities affecting the microcirculation of patients with a clinical diagnosis of VBI compared with controls. CONCLUSION: MRA failed to reveal abnormalities in patients with a clinical diagnosis of VBI compared with controls. The PI of the basilar artery, measured using TCD, demonstrated high sensitivity (91%) and specificity (91%) for detecting clinically diagnosed VBI.

Introduction. Surgical posterior fossa decompression of Chiari malformation type 1 (CM-I) is recommended in symptomatic patients. The classic surgery is a suboccipital craniectomy and C-1 laminectomy, with duroplasty. However, a range of complications associated with surgical management of CM-I includes pseudomeningocele, CSF leakage, aseptic meningitis, and wound infections, making dural closure and reconstruction one important step to determine morbidity. Our objective is to present a technique of pericranium harvest and dural closure and describe our experience. Methods. A retrospective study was conducted based on records of patients treated in Hospital das Clínicas of the University of São Paulo, diagnosed with CM-I and submitted to posterior fossa decompression from January 2008 until May 2015. We evaluated the occurrence of post-operative complications of symptomatic pseudomeningocele or incisional CSF leak. The occurrence of meningitis, surgical site infection or other complications were also available. Results. A total of 22 patients were evaluated in this study. Sixteen (72.7%) were female patients. Overall, the mean age at the time of surgery was 49 ± 13.6 years-old. Four patients (18%) presented complications: 3 CSF leakages (13.5%) and 1 pseudomeningocele (4.5%). Discussion. Postoperative complications of CM-I are still frequent and determinants of surgical success. We propose a new surgical technique with autologous pericranium graft and duraplasty. Additionally to dural closure, we propose another modality of muscular fascia closure, allowing increased tight closure. Our data corroborate with current literature. Conclusion. Our technique of dural closure using pericranium autologous graft in CM-I is safe and feasible.

Introduction Treatment of hydrocephalus is accomplished primarily through a ventricular-peritoneal shunt (VPS). This study aims to describe the application of retrograde ventricle-sinus shunt (RVSS) in patients with hydrocephalus after surgical treatment of myelomeningocele. Method A prospective, randomized and controlled pilot study. We consecutively enrolled 9 patients with hydrocephalus after surgical repair of myelomeningocele from January 2010 to January 2012. These patients underwent elective RVSS or VPS. Five underwent RVSS and 4 underwent VPS. Patients were followed for one year with quarterly evaluations and application of transcranial Doppler. Results RVSS group showed outcomes similar to those of VPS group. Doppler revealed significant improvement when comparing preoperative to postoperative period. RVSS group had significantly higher cephalic perimeter than VPS group. Neuropsychomotor development, complications and subjective outcomes did not differ between groups. Conclusion RVSS shunt is viable; it is an alternative option for the treatment of hydrocephalus. RESUMO O tratamento da hidrocefalia é realizado principalmente através de uma derivação ventrículo-peritoneal (DVP). Nosso objetivo é descrever a aplicação da derivação ventrículo-sinusal retrógrada (DVSR) em pacientes com hidrocefalia após o tratamento cirúrgico de mielomeningocele. Método Estudo prospectivo, randomizado e controlado. Selecionados consecutivamente 9 pacientes com hidrocefalia após correção cirúrgica de mielomeningocele de janeiro de 2010 a janeiro de 2012. Eles foram submetidos à DVSR ou DVP. Cinco foram submetidos à DVSR e 4 à DVP. Foram seguidos por 1 ano com realização trimestral de avaliações e aplicação do Doppler transcraniano. Resultados O grupo DVSR apresentou desfechos semelhantes ao grupo DVP. O Doppler mostrou melhora significativa quando comparado o pré-operatório com o pós-operatório. O grupo DVSR apresentou perímetro cefálico significativamente maior que o grupo DVP. O desenvolvimento neuropsicomotor e complicações não diferiram entre os grupos. Conclusão A derivação ventrículo-sinusal retrógrada é viável; ela é uma opção para o tratamento de hidrocefalia.

Highlights • Dynamic cerebral blood flow autoregulation is impaired on the first day following cardiac surgery. • Autoregulation index before and after surgery is predictive of post-operative delirium. • Patients with impaired dynamic cerebral autoregulation at 24 h and 7 days after surgery had a higher incidence of delirium., Objective We investigated the potential association of cerebral autoregulation (CA) with postoperative delirium (PD), a common complication of cardiac surgery with cardiopulmonary bypass (CPB). Methods In patients undergoing coronary artery bypass graft (CABG) surgery with CPB, cerebral blood flow velocity (CBFV) and blood pressure (BP) were continuously recorded during 5-min preoperatively (T1), after 24 h (T2), and 7 days after procedure (T3). Prospective multivariate logistic regression analysis was performed to determine the independent risk factors of PD. Autoregulation index (ARI) was calculated from the CBFV response to a step change in BP derived by transfer function analysis. Results In 67 patients, mean age 64.3 ± 9.5 years, CA was depressed at T2 as shown by values of ARI (3.9 ± 1.7), compared to T1 (5.6 ± 1.7) and T3 (5.5 ± 1.8) (p

Background. This study aimed to analyse cerebral autoregulation (CA) during induction and treatment of intracranial hypertension (ICH) in an experimental model. Materials and Methods. Landrace and Duroc piglets were divided into mild and severe ICH groups. Four or seven millilitres of saline solution was infused into paediatric bladder catheter inserted in the parietal lobe (balloon inflation). After 1.5 h, a 3% saline solution was infused via venous catheter, and 30 min later, the bladder catheter balloon was deflated (surgery). The cerebral static autoregulation (sCA) index was evaluated using cerebral blood flow velocities (CBFV) obtained with Doppler ultrasound. Results. Balloon inflation increased ICP in both groups. The severe ICH group showed significantly lower sCA index values (p=0.001, ANOVA) after balloon inflation (ICH induction) and a higher sCA index after saline injection (p=0.02) and after surgery (p=0.04). ICP and the sCA index were inversely correlated (r=−0.68 and pr=0.74 and p Conclusion. ICH was associated with local balloon expansion, which triggered CA impairment, particularly in the severe ICH group. Moreover, ICP-reducing treatments were associated with improved CA in subjects with severe ICH.

To present a systematic review and meta-analysis to establish the relation between cerebral autoregulation (CA) and intracranial hypertension.An electronic search using the term "Cerebral autoregulation and intracranial hypertension" was designed to identify studies that analyzed cerebral blood flow autoregulation in patients undergoing intracranial pressure (ICP) monitoring. The data were used in meta-analyses and sensitivity analyses.A static CA technique was applied in 10 studies (26.3%), a dynamic technique was applied in 25 studies (65.8%), and both techniques were used in 3 studies (7.9%). Static CA studies using the cerebral blood flow technique revealed impaired CA in patients with an ICP ≥20 (standardized mean difference [SMD] 5.44%, 95% confidence interval [CI] 0.25-10.65, P = 0.04); static CA studies with transcranial Doppler revealed a tendency toward impaired CA in patients with ICP ≥20 (SMD -7.83%, 95% CI -17.52 to 1.85, P = 0.11). Moving correlation studies reported impaired CA in patients with ICP ≥20 (SMD 0.06, 95% CI 0.07-0.14, P0.00001). A comparison of CA values and mean ICP revealed a correlation between greater ICP and impaired CA (SMD 5.47, 95% CI 1.39-10.1, P = 0.01). Patients with ICP ≥20 had an elevated risk of impaired CA (OR 2.27, 95% CI 1.20-4.31, P = 0.01).A clear tendency toward CA impairment was observed in patients with increased ICP.

Subarachnoid hemorrhage is frequently associated with poor prognoses. Three different hemodynamic phases were identified during subarachnoid hemorrhage: oligemia, hyperemia, and vasospasm. Each phase is associated with brain metabolic changes. In this review, we correlated the hemodynamic phases with brain metabolism and potential treatment options in the hopes of improving patient prognoses.

Resumo Objetivo: Neste trabalho temos o objetivo de avaliar a acurácia do sistema de aferição da pressão intracraniana (PIC) epidural com microchip. Métodos: Foram estudados 27 suínos sob anestesia geraI, devidamente assistidos com monitoração ventilatória e hemodinâmica. Durante o experimento foi reproduzido um processo expansivo intracerebral programado no lobo frontal direito. O experimento constou de três grupos (A, B e C) com hipertensão intracraniana gerada com balão reproduzindo um hematoma intracerebral. Em todos os grupos foram calibrados os parâmetros normais: os dois sistemas de PIC foram comparados e estudados quanto à correlação dos valores aferidos. Resultados: O comportamento médio da PIC ao longo dos momentos de avaliação foi estatisticamente diferente entre os grupos (p < 0,001). A reprodução de ressangramento resultou em elevação significativa da PIC (p < 0,001). Avaliando-se a acurácia comparativa geral, verificou-se um coeficiente de correlação intraclasse de 0,8. Conclusão: O modelo de hipertensão intracraniana por balão em suínos é factível e confiável na geração de hipertensão intracraniana. O sistema de aferição de pressão intracraniana epidural apresenta elevado coeficiente de correlação com o sistema de aferição parenquimatoso na avaliação global.

Introdução: Os principais objetivos do tratamento das metástases cerebrais (MC) são no auxílio do controle da doença no encéfalo e a melhora da qualidade de vida dos pacientes. A cirurgia convencional tem um importante papel no tratamento das MCs e os métodos de monitoração intraoperatória podem auxiliar na obtenção de resultados cirúrgicos melhores. Objetivos: Avaliar a influência da ultrassonografia encefálica durante cirurgia para ressecção de MC no índice de Karnofsky e no grau de ressecção do tumor. Métodos: Neste estudo prospectivo controlado e não randomizado, doentes com indicação de tratamento cirúrgico de MCs foram incluídos. A ultrassonografia intraoperatória (USIO) foi realizada por um neurossonologista. O índice de Karnofsky foi avaliado por equipe multidisciplinar de oncologia; o grau de dificuldade para ressecção cirúrgica do tumor foi avaliado pelo cirurgião e o volume tumoral foi avaliado pelo neurorradiologista por meio da RM realizada no pré e pós-operatório. Resultados: Dos 78 doentes, 40 homens e 38 mulheres com idade média de 53 anos, 35 foram submetidos a tratamento cirúrgico com auxílio da USIO. Não houve diferença estatística no KPS e volume tumoral pré-operatório entre os grupos. O KPS pós-operatório no grupo da USIO foi de 80 e no grupo-controle de 70 (p=0,045). Considerando-se a melhora do KPS no pós-operatório, a quantidade de doentes tiveram melhora do KPS foi superior no grupo da USIO (p=0,036) destacando-se os seguintes subgrupos: tumores com grau de dificuldade de ressecção < 4 (p=0,037), tumores nas áreas eloquentes (p=0,043), tumores não relacionados aos grandes vasos e nervos (p=0,007), e lesões únicas no leito cirúrgico (p=0,038). O tumor residual na RM pós-operatória foi menor no grupo da USIO: 9,5% no grupo da USIO e 30,8% no grupo-controle; 1,6 mm3 no grupo da USIO e 9 mm3 do grupo-controle; p=0,05. Considerando-se doentes com KPS >= 70, o número de doentes com volume de tumor residual inferior a 10% em relação ao volume pré-operatório foi superior no grupo da USIO (p=0,032 e OR de 3,8). Conclusão: Os achados deste estudo sugerem que a USIO encefálica pode influenciar na melhora do índice de Karnofsky e na redução do volume de tumor residual Object: The goals of treating a cerebral metastasis (CM) are to achieve local control of the disease and to improve patient quality of life. The aim of this study was to analyse the effect of using conventional surgery supported by intra-operative ultrasound (IOUS) to approach a CM. To perform this analysis, we determined Karnofsky post-operative scores (KPS) and tumour resection grades. Methods: Patients with CM who were eligible to undergo a surgical approach were included in this study. Surgical treatment was either supported or not supported by IOUS. A neural oncology team determined the pre- and post-operative KPS. A radiologist examined the tumour volume using pre- and post-operative magnetic resonance imaging. Before the surgery, the surgeon determined whether it was possible to perform a total CM resection. Results: A total of 78 patients with CM diagnosis were treated using a surgical approach (35 with and 43 without IOUS). The post-operative median KPS was higher in the IOUS group (80 versus 70, p=0.045). Within the IOUS group, KPS evolution was superior (p=0.036), especially in the following CM subgroups: a difficulty of tumour resection ranking score= 70, the residual tumour volume was categorized as < 10% or >= 10%, and 62% of patients had < 10% residual tumours (76% in the IOUS group and 45% in the non-IOUS group; p=0.032 and OR=3.8). Conclusion: This study suggests that IOUS can play a role in improving post-operative KPS and in decreasing residual tumours in CM surgeries

Chiari malformation type I (CM) is the main congenital malformation disease of the craniovertebral junction. The ideal surgical treatment is still controversial. Invasive procedures inside the cerebrospinal fluid (CSF) space and associated with dural repair are considered the gold standard; however, less invasive surgery with isolated bone decompression without dural opening may be possible in selected patients. Our study evaluates the efficacy of intraoperative CSF flow measurement with ultrasonography (USG) as a determining parameter in the selection of these patients.We analyzed prospectively 49 patients with CM operated on at the Hospital das Clínicas, College of Medicine, University of São Paulo. Patients underwent decompressive surgery with or without opening of the dura mater after intraoperative USG measuring flow rate. A value of 3 cm/second was considered a cutoff. Quality of life before and after surgery and the improvement of neck pain and headache were evaluated.Among 49 patients enrolled, 36 patients (73%) had CSF flow3 cm/second and did not undergo duraplasty. In 13 patients (27%) with initial flow3 cm/second, dural opening was performed together with duraplasty. All patients improved when preoperative and postoperative scores were compared, and all clinical parameters evaluated did not differ between both surgical groups. Patients submitted to bone decompression alone had a lower complication rate.Intraoperative USG with measurement of CSF allows the proper selection of patients with CM for less invasive surgery with bone decompression without duraplasty.

Objective Intracranial hypertension (IH) develops in approximately 50% of all patients with severe traumatic brain injury (TBI). Therefore, it is very important to identify a suitable animal model to study and understand the pathophysiology of refractory IH to develop effective treatments. Methods We describe a new experimental porcine model designed to simulate expansive brain hematoma causing IH. Under anesthesia, IH was simulated with a balloon insufflation. The IH variables were measured with intracranial pressure (ICP) parenchymal monitoring, epidural, cerebral oximetry, and transcranial Doppler (TCD). Results None of the animals died during the experiment. The ICP epidural showed a slower rise compared with parenchymal ICP. We found a correlation between ICP and cerebral oximetry. Conclusion The model described here seems useful to understand some of the pathophysiological characteristics of acute IH. Objetivo A hipertensão intracraniana (HIC) ocorre em até 50% de todos os pacientes com traumatismo cranioencefálico (TCE). Por isso, é importante estabelecer um modelo animal adequado para estudar a fisiopatologia da HIC refratária, com a perspectiva de desenvolver tratamentos eficazes. Métodos Os animais foram submetidos a um protocolo padrão de anestesia. A hipertensão intracraniana foi estabelecida através de insuflação de um balão. As variáveis HIC foram medidas com a pressão intracraniana (PIC) do parênquima, oximetria, epidural e doppler transcraniano. Resultados A PIC epidural apresentou elevação mais lenta, comparada com a PIC parenquimal. Houve correlação entre a PIC e a oximetria cerebral. O registro da PIC, oximetria e índice de pulsatilidade foi realizado em todos os animais sem dificuldade. Conclusão O modelo descrito parece ser útil para a compreensão de algumas características fisiopatológicas na HIC aguda.

Patients with ischemic heart failure (iHF) have a high risk of neurological complications such as cognitive impairment and stroke. We hypothesized that iHF patients have a higher incidence of impaired dynamic cerebral autoregulation (dCA). Adult patients with iHF and healthy volunteers were included. Cerebral blood flow velocity (CBFV, transcranial Doppler, middle cerebral artery), end-tidal CO2 (capnography), and arterial blood pressure (Finometer) were continuously recorded supine for 5 min at rest. Autoregulation index (ARI) was estimated from the CBFV step response derived by transfer function analysis using standard template curves. Fifty-two iHF patients and 54 age-, gender-, and BP-matched healthy volunteers were studied. Echocardiogram ejection fraction was 40 (20–45) % in iHF group. iHF patients compared with control subjects had reduced end-tidal CO2 (34.1 ± 3.7 vs. 38.3 ± 4.0 mmHg, P < 0.001) and lower ARI values (5.1 ± 1.6 vs. 5.9 ± 1.0, P = 0.012). ARI