Outcome for patients with carotid stenosis undergoing carotid endarterectomy, the cerebral condition followed by extra/intracranial ultrasound examinations.

Seventy-six patients undergoing carotid endarterectomy were studied to estimate the effect of operation, evaluate the accessible methods of examination and disclose the complications owing to the operation. In addition, the hypothesis that the pulsatility index in MCA measured by the Doppler method could disclose severe ischemia and risk of complications during endarterectomy was tested. The study was a prospective study of patients operated at the University Hospital in Odense in the years 1991-1996.

Cerebral infarct following carotid endarterectomy. Frequency, clinical and hemodynamic significance evaluated by MRI and TCD.

The purpose of this study was to disclose the frequency of new infarcts after Carotid Endarterectomy (CEA) by MRI and Transcranial Doppler examinations (TCD), and to evaluate the clinical and pathological significance. Of a consecutive series of 41 patients with a symptomatic carotid stenosis exceeding 69%, 33 had MRI and TCD examinations performed before and after the CEA. Pre-operative MRIs revealed Focal High Signal Intensity (FHSI) in 21 patients (64%) on the side of the stenosis, ranging in number from 2 to more than 20 and in size from 0.

Percutaneous transluminal angioplasty in selected patients with severe carotid artery stenoses: the results of a consecutive series of 24 patients.

Objectives: To assess clinically and with duplex scanning the results of percutaneous transluminal angioplasty in a subgroup of patients with carotid artery stenosis.

Design: A retrospective study.

Materials: Twenty-four patients with focal hemispheric neurological symptoms from a concentric, smooth carotid stenosis more than 70% treated with balloon dilatation.

Transcranial Doppler recordings in raised intracranial pressure.

The pulsatility index (PI) registered by the transcranial doppler (TCD) was examined in relation to arterial pCO2 (paCO2) and epidural pressure (ICP). In 10 normal subjects PI was studied during variations in paCO2. In 10 neurosurgical patients with head injuries concomitant measurements of PI and ICP were obtained.

[Apoplexy--the acute phase].

This review concerns the acute phase of stroke. It describes incidence, prevalence, etiology, diagnosis and treatment together with the possibilities for prevention. The incidence of stroke in the Danish population is about 2/1000 person years and has been largely unchanged during the last 20 years.

[Apoplexy--the acute stage].

This review concerns the acute phase of stroke. It describes incidence, prevalence, etiology, diagnosis and treatment together with the possibilities for prevention. The incidence of stroke in the Danish population is about 2/1000 person years and has been largely unchanged during the last 20 years.

Cerebral blood flow and metabolism following subarachnoid haemorrhage: effect of subarachnoid blood.

The amount of effused blood following a subarachnoid haemorrhage (SAH) was estimated in 48 patients by cerebral computerized tomographic scanning. The cerebral oxygen consumption (CMRO2) was calculated as arteriovenous difference for oxygen multiplied by mean cerebral blood flow measured by the 133-Xe inhalation technique. A significant negative correlation was observed between CMRO2 and amount of subarachnoid blood, with additional reduction in CMRO2 in case of ventricular bleeding.

Spasm index in subarachnoid haemorrhage: consequences of vasospasm upon cerebral blood flow and oxygen extraction.

A spasm index, defined as transcranial Doppler detected flow velocity in the middle cerebral artery divided by regional cortical cerebral blood flow (CBF), was used on 24 patients with subarachnoid haemorrhage (SAH). The aim was to estimate degree and time course of vasospasm, even in cases with great day-to-day variation in CBF, and correlate to CBF and oxygen extraction. All patients showed increase in spasm indices with peak index in the second or third week.

Cerebral blood flow and metabolism following subarachnoid haemorrhage: cerebral oxygen uptake and global blood flow during the acute period in patients with SAH.

Forty-eight patients with subarachnoid haemorrhage were studied with repeated rCBF and CMRO2 measurements. Cortical rCBF was measured using xenon-inhalation technique. CMRO2 was calculated as AVDO2 x CBF.

Relation between angiographic cerebral vasospasm and regional CBF in patients with SAH.

The relation between angiographically determined cerebral vasospasm following a subarachnoid hemorrhage and regional cerebral blood flow (CBF) was studied in 63 investigations of 45 patients. The CBF was measured using the intra-arterial 133-Xe clearance technique within one hour of angiography. A positive correlation between regional CBF and diameter of major supplying vessel was observed.

Problems in cerebral blood flow calculation using xenon-133 in patients with pulmonary diseases.

We used the end-tidal concentration of xenon-133 (air curve) to estimate the profile of its arterial concentration in calculating cerebral blood flow. We examined the effects of pulmonary disease and artificial ventilation on the air curve and the calculated cerebral blood flow. We studied the relation between arterial and end-tidal xenon activities in 19 subjects, of whom 15 had pulmonary dysfunction.

Retrograde catheterization of the right internal jugular vein for serial measurements of cerebral venous oxygen content.

Serial measurements of CBF and metabolism require multiple cerebral venous blood samples. Retrograde catheterization of the right internal jugular vein is easily performed at a point 2.5-3 cm lateral to, and 2 cm above, the medial end of the right clavicula.

Reversible ischemic neurological deficit and minor strokes before and after EC/IC bypass surgery. A neuropsychological study.

Thirty-three patients with reversible ischemic deficits or completed minor strokes had their cerebral function measured neuropsychologically a few days before and 3 months after extra-intra cranial bypass surgery. Three months post-operatively bypass patency was demonstrated by angiography. Ten patients were operated on the right side and 23 on the left side.

CBF in head injury.

In the last few years the possibility of measuring CBF by means of intravenous isotop injection technique and portable monitor has made the use of measuring CBF in the clinical setting of the brain injured patient of current interest. However, knowledge about the hemodynamics of the head trauma is inevitable for the interpretation of the CBF results. In this communication a short outline of the results obtained during the last decades studies about the hemodynamic of the damaged brain is given.

A neuropsychological study of 12 patients with transient ischemic attacks before and after EC/IC bypass surgery.

A neuropsychological study of 12 patients with transient ischemic attacks from the carotid artery territory was carried out about 2 months following their latest attack, about a week before STA/MCA bypass operation, and again 3 months postoperatively. The results suggest that the TIA patients as a group were slightly intellectually impaired preoperatively. After the operation, a minor neuropsychological improvement had taken place although they still were not fully intellectually rehabilitated.

Regional CBF, intraventricular pressure, and cerebral metabolism in patients with ruptured intracranial aneurysms.

Regional cerebral blood flow (rCBF), cerebral metabolic rate of oxygen (CMRO2), intraventricular pressure, and lactate/pH levels in the cerebrospinal fluid (CSF) were measured in 38 patients with ruptured intracranial aneurysms between the 3rd and 13th day after subarachnoid hemorrhage (SAH). Angiography was performed following the rCBF study and the degree of vasospasm was measured on the angiograms. The patients were graded clinically according to the system of Hunt and Hess.

Cerebrovascular reactivity in patients with ruptured intracranial aneurysms.

The cerebral vasomotor reactivity to arterial hypotension and hypocapnia was studied in 34 patients between the 3rd and 13th day after rupture of an intracranial saccular aneurysm. Using the intra-arterial xenon-133 injection method, regional cerebral blood flow (rCBF) and cerebral metabolic rate of oxygen (CMRO2) were measured. The intraventricular pressure and cerebrospinal fluid (CSF) lactate and pH levels were determined.

Intracranial pressure changes following aneurysm rupture. Part 3: Recurrent hemorrhage.

Continuous monitoring of intraventricular pressure (IVP) was performed before and during 13 recurrent hemorrhages occurring in 10 patients between the 3rd and 14th day after the initial rupture of an intracranial saccular aneurysm. Before re-rupture, nine patients were of Hunt and Hess' clinical Grade III of IV. Severe angiographic vasospasm was demonstrated in six patients.

CSF serotonin concentrations and cerebral arterial spasm in patients with ruptured intracranial aneurysm.

In 26 patients with recent rupture of an intracranial saccular aneurysm the CSF concentrations of serotonin (5-HT) were measured repeatedly by a radioimmunoassay. The 5-HT level in ventricular CSF collected between the 2nd and 15th day after SAH ranged between less than 2 and 5 nmol/l. These did not differ from the levels found in the ventricular CSF (less than 2-3 nmol/l) and lumbar CSF (less than 2-3 nmol/l) of control patients.

Intracranial pressure changes following aneurysm rupture. Part 2: associated cerebrospinal fluid lactacidosis.

Lactate concentrations and pH were measured serially in the cerebrospinal fluid (CSF) of 52 patients with ruptured intracranial aneurysms. Measurements were made during continuous monitoring of the intraventricular pressure (IVP) in the first 12 days after the initial subarachnoid hemorrhage. A total of 226 samples of CSF were analyzed.

Intracranial pressure changes following aneurysm rupture. Part 1: clinical and angiographic correlations.

Intraventricular pressure (IVP) was measured continuously by the method of Lundberg for an average period of 8 days in 52 patients with recent rupture of an intracranial saccular aneurysm. The patients were graded as follows according to the system of Hunt and Hess: 13 patients were Grades I-II, 19 patients Grades II-III, and 20 patients Grades III-V. The degree of cerebral arterial spasm was measured on angiograms taken on admission and approximately 7 days later.

Focal cerebral ischemia measured by the intra-arterial 133xenon method. Limitations of 2-dimensional blood flow measurements.

The limitations of 2-dimensional isotope techniques in the study of focal cerebral ischemia were investigated using the intra-carotid 133 xenon injection method and a 254 multidetector scintillation camera. To make sure that the detectors "look" directly on infarcted areas, only patients with infarcts involving cortical surface structures were included in the study. Eleven such patients were found among 43 consecutive patients with completed stroke, all investigated with CT-scan.

Focal cerebral hyperemia in acute stroke. Incidence, pathophysiology and clinical significance.

In a consecutive study comprising 41 patients with completed stroke of less than 72 hours duration, cerebral angiography and measurements of the regional cerebral blood flow (rCBF) were performed within 24 hours after admission. The rCBF study was done using the 133-Xenon intracarotid injection method and a 254 multi-detector camera. CT scan was done 24 hours after the rCBF study.

Reproducibility of regional cerebral blood flow measurements in acute severe head injury.

In order to evaluate the reproducibility of regional cerebral blood flow (rCBF) measurements in pathological brain tissue, serial measurements were carried out in 13 determinations performed in patients who were comatose after severe head injuries within the first 2 weeks after the head trauma. The xenon-133 intra-arterial method was used for the flow measurements, and the flow was studied separately in 16 areas of the brain, producing 197 regional double determinations. The patients were maintained in a steady state during and between the measurements, and only differences of less than 2 mm Hg in the arterial CO2 pressure and less than 5 mm Hg in the perfusion pressure were tolerated.