S. Tromp 1, M. Braat 2, J. Van Der Heijden 3, M. Van Egdom 1, P. Dekker 1, M. Haringsma 1, J. Vos 2
1 Department of Clinical Neurophysiology,
2 Department of Radiology,
3 Department of Cardiology, St. Antonius Hospital – Nieuwegein, Netherlands

Objective: We studied effects of stent design on embolisation detected by transcranial Doppler during carotid artery stenting.

Material and Methods: We studied 711 carotid stent procedures performed between December 1997 and January 2012. Three stent-types were studied: open-cell (Acculink: free cell area 11.48 mm2, n=271), semi-closed cell (Precise: 5.89 mm2, n=144) and closed-cell (Carotid Wall: 1.08 mm2, n=296). Cerebral embolisation was measured by transcranial Doppler of the ipsilateral middle cerebral artery. Isolated microembolisms and microembolic showers (cardiac cycles with too many emboli to count separately) were counted.

A. Chiti 1, N. Giannini 1, F. De Caro 2, G. Gialdini 1, E. Terni 1, E. Giorli 1, M. Puglioli 3, M. Cosottini 3, A. S. Petronio 2, G. Orlandi 1
1 Neurological Clinic,
2 Cardiothoracic Department, University of Pisa – Pisa,
3 Unit of Neuroradiology, Azienda Ospedaliero-Universitaria Pisana – Pisa, Italy

Objective: The risk of transient ischemic attack and stroke following transfemoral aortic valve implantation (TAVI) is 2-10% and is even higher considering silent ischemic brain injury. Periprocedural microembolic signals (MES) and hemodynamic changes (HC) may be considered physiopathological markers of such events. We show neurosonological and neuroradiological data about a patient submitted to TAVI.

Material and Methods: A 78-year-old man underwent TAVI. During the procedure, continuous monitoring of right middle cerebral artery was performed by transcranial Doppler (TCD), in order to reveal MES and HC (left acoustical temporal bone window was inadequate). Moreover, patient underwent brain magnetic resonance with diffusion-weighted sequences (MR-DWI) before and after TAVI.

M. De Lima Oliveira, M. Fernandes De Oliveira, K. Andrade Norremose, S. Brasil Lima, F. Campos Gomes Pinto, H. Matsushita, M. Jacobsen Teixeira, E. Bor-Seng-Shu
Department of Neurology, University Hospital, University of São Paulo – São Paulo, Brazil

Objective: Treatment of hydrocephalus is still a challenge to medicine. Currently, the retrograde ventriculo-sinus shunt (RVSS) is proposed in order to solve the question of ventricular catheterization complications related to siphoning. Transcranial Doppler can evaluate intracranial hypertension relief after this surgical procedure measuring brain blood flow velocities, pulsatility and resistivity index.

M. De Lima Oliveira, M. Fernando Paschoal Junior, K Almeida Lins, R. Carvalho De Nogueira, M. Jacobsen Teixeira, E. Bonr-Seng-Shu
Department of Neurology, University Hospital, University of São Paulo – São Paulo, Brazil

Objective: The clinical course of patients with fulminant hepatic failure (FHF) is often worsened by loss autoregulation of cerebral blood flow (CBF), which leads to cerebral edema and intracranial hypertension. The development these complications is an important event in patients with FHF that needs intensive care and urgent liver transplantation. To evaluate the hemodynamic and cerebrovascular autoregulation capacity of patients with fulminant hepatic failure before and after liver transplantation and those not undergoing transplantation.

M. De Lima Oliveira, M. Mendes Paschoal Junior, K. Almeida Lins, R. Carvalho De Nogueira, M. Krajnyk De Azevedo, E. Santos Junior, M. Jacobsen Teixeira, E. Bor-Seng-Shu
Department of Neurology, University Hospital, University of São Paulo – São Paulo, Brazil

Introduction: The cerebral vasospasm is considered one of the most common and serious complications of Subarachnoid hemorrhage (SAH) can be a cause of neurological ischemic transient or permanent, and contributes to increased rates of morbidity and mortality of patients. Previous studies suggested that intracranial aneurysms can act as sources of distal embolization. Spontaneous thrombus can be observed within the aneurysmal sac, presumably because of turbulence and slow flow. The aim of this study was to describe the detection of some MES during routine vasospasm monitoring by transcranial Doppler (TCD).

O. Kim 1, S. An 1, S. Oh 1, J. Kim 1, W. Kim 2
1 CHA Bundang Medical Center, CHA University – Seongnam,
2 Kangdong Sacred Heart Hospital, Hallym University College of Medicine – Seoul, South Korea

Objective: Lacunar infarction was considered due to occlusion of small penetrating artery and disease of small cerebral arteriole. Transcranial Doppler (TCD) pulsatile index (PI) has been interpreted as a marker for distal vascular resistance and reflects microangiopahty in cerebral arteries. Therefore, we hypothesized that increased PI might be associated with more large infarct size due to progressed underlying microangiopathy in patients with acute lacunar stroke.

Material and Methods: We included 69 patients with acute lacunar stroke who completed TCD. We used mean PI value of both MCA for analysis. Infarct size was a maximal diameter of acute lesion based on diffusion weighted MRI.

M. De Lima Oliveira, B. Lembo Conde De Paiva, R. Faria Simm, P. Henrique Pires Aguira, E. Bor-Seng-Shu
Department of Neurology, Hospital Santa Paula – São Paulo, Brazil

Objective: Cerebral vasospasm following SAH is one of the main causes of secondary brain injury. The incidence peak is between the 7th and 14th day after bleeding. The management of cerebral vasospasm is based on the triple H therapy, although this therapy may not be enough to control the vasospasm complications. In these cases, mechanical or pharmacological angioplasty on the affected vessel may be indicated if neurological deterioration occurs. Sedated or comatose patients make clinical evaluation difficult and limited. Combining different brain monitoring techniques can provide valuable information that help physicians to identify patients before clinical deterioration.

S. Tromp 1, M. Braat 2, J. Van Der Heijden 3, M. Van Egdom 1, P. Dekker 1, M. Haringsma 1, J. Vos 2
1 St Antonius Hospital, Department of Clinical Neurophysiology,
2 St Antonius Hospital, Department of Radiology,
3 St Antonius Hospital, Department of Cardiology – Nieuwegein, Netherlands

Objective: This study was conducted to determine if the use of an emboli protection device prevented distal embolisation in carotid stenting procedures.

Material and Methods: We retrospectively analyzed data of 837 carotid stent procedures between December 1997 and January 2012. Cerebral embolisation was monitored using transcranial Doppler of the ipsilateral middle cerebral artery. Isolated microembolic signals and microembolic showers (cardiac cycles with too many embolisms to count separately) were counted.

E. Vicenzini 1, P. Pulitano 1, R. Cicchetti 2, P. Papov 2, G. Spadetta 3, M. Rocco 3, V. Di Piero 1, G. L. Lenzi 1, O. Mecarelli 1
1 Department of Neurology and Psychiatry,
2 Neonatal Intensive Care Unit,
3 Transplant Coordinator, Intensive Care Unit. Sapienza, University of Rome – Rome, Italy

Objective: Transcranial Doppler is sensitive technique for the diagnosis of cerebral circulatory arrest in brain death, when specific patterns such as reverberant flow and short systolic spikes are observed in intracranial arteries. These patterns are related to the occurrence of brain swelling in the inextensible skull, resulting in transformation from a normal “low-resistance” into a “high-resistance” brain parenchyma. In infants, the non-ossified fontanelles initially compensates for intracranial hypertension. We describe TCD patterns in infants with brain death, different from adults, with the hemodynamic modifications induced by anterior fontanelle compression.

V. Zetola
Federal University of Parana – Curitiba, Brazil

Stroke is an important complication of sickle cell disease. Approximately twenty-four percent of patients have a stroke by the age of 45 years. Blood transfusions decrease stroke risk in patients deemed high risk by transcranial Doppler (TCD) by evidence of elevated intracranial internal carotid or middle cerebral artery velocity. A follow-up of neurologically symptomatic and asymptomatic sickle cell patients increased other factors were significant in the identification of patients at risk that could include: velocity in the ophthalmic artery > that of the ipsilateral MCA, maximum velocity in the posterior cerebral (PCA), vertebral, or basilar arteries > maximum velocity in the MCA, turbulence, PCA visualized without the MCA.

W. Mess
University Hospital – Maastricht, Netherlands

It has been shown for different patient categories that the detection of microembolic signals (MES) in the middle cerebral artery helps to estimate the risk of future cerebrovascular events. The strength of the evidence for this relationship differs for the different clinical situations. So, the question whether automated MES detection should be applied in the daily clinical context depends not only on the adequacy of the detection system. However, a properly functional system is a prerequisite for its succesful clinical application. This comprises not only the correct identification of MES in the transcranial Doppler signal but also the ease of use. Only if both criteria are fulfilled automated MES detection is likely to be used in clinical practice. Several automated MES detection systems are currently commercially available.

R. Aaslid
Hemodynamics AG – Bern, Swaziland

Objective: Earlier attempts at non-invasive determination of ICP used ABP and TCD waveforms to estimate critical closing pressure (CCP). However, the CCP was found to be strongly influenced by vascular tone and a poor indicator of absolute ICP levels.

Material and Methods: An important effect of raised ICP is a decrease in intracranial compliance. This, in turn, causes the pulsations in the ICP waveform to increase. These pulsations are primarily caused by the changes in cerebral blood volume (CBV) throughout the heart cycle. We investigated a relatively simple model of the cerebral circulation where the relative changes in CBV were determined by integrating the difference between the arterial flow velocity (FV) waveform as recorded by TCD, and the venous outflow which we assumed to be non-pulsatile.