The influence of ruptured cerebral aneurysm localization on the blood flow velocity evaluated by transcranial Doppler ultrasonography

Cerebral Vasospasm After Spontaneous Subarachnoid Hemorrhage: Angiographic Pattern and Its Impact on the Clinical Course

OBJECTIVE

To analyze angiographic characteristics of cerebral vasospasm (CVS) after spontaneous subarachnoid hemorrhage (sSAH) and their potential impact on secondary infarction and functional outcome.

METHODS

Demographic, clinical, and imaging data of sSAH patients with angiographic CVS admitted over a 6-year period were retrospectively analyzed.

RESULTS

A total of 85 patients were included in the final analysis. A total of 311 arterial territories in 85 angiographies demonstrated angiographic CVS. The anterior cerebral artery (ACA) was the most common site of angiographic CVS (42.1%), followed by the middle cerebral artery (MCA) (26.7%). In 29 angiographies (34%) CVS was found in more than 3 vessels and a bilateral pattern was identified in 53 cases (62%). Older age (OR 3.24 [95% CI 1.30-8.07], P = 0.012) was identified as the only significant risk factor for CVS-related infarction (OR 22.67, P = 0.015). Unfavorable outcome was associated with older age (OR 3.24, P = 0.023) and poor World Federation of Neurosurgical Societies grade (OR 3.64, P = 0.015). Analyses of angiographic characteristics did not reveal any risk factors for unfavorable outcome. We identified distal CVS as a significant risk factor for CVS-related infarction (OR 2.89, P = 0.026).

CONCLUSIONS

Angiographic CVS after sSAH shows a specific distribution pattern in favor of ACA and MCA and in most cases 2-3 affected vessels are affected, often bilaterally. Patients exhibiting distal CVS have a higher risk for CVS-related infarction and should be observed closely. Nonetheless, the majority of angiographic characteristics did not allow conclusions about functional outcome nor the occurrence of CVS-related infarction in sSAH patients.

A comparison of transcranial Doppler and magnetic resonance imaging for long term changes in middle cerebral artery stenosis

OBJECTIVES

Intracranial arterial stenosis may progress or regress, of which the diagnosis is important to predict the risk of stroke or to evaluate the response of treatment. Transcranial Doppler (TCD) seems to be useful for this purpose, however, optimal diagnostic criteria have not been validated yet. Our study was designed to compare TCD changes with magnetic resonance angiography (MRA) to validate optimal TCD criteria for progression or regression of middle cerebral artery (MCA).

PATIENTS AND METHODS

We prospectively enrolled patients who visited our neurology department due to MCA stenosis on TCD examination. Brain MRA was used to identify patients with stenosis of the same site of MCA. Progression or regression was defined by change of MRA grading (normal, mild, moderate, severe or occlusion). Various criteria of mean flow velocity (MFV) difference and percent change were assessed. To register more patients for reliable analysis, additional patients with the same inclusion criteria were recruited retrospectively. All patients enrolled in the study were symptomatic or asymptomatic atherosclerotic MCA stenosis.

RESULTS

Eighteen patients were enrolled and 21 MCAs with completed follow-up TCD and MRA were analyzed (mean age 68.4 years, mean follow-up 17.8 months). In addition, 40 MCAs from 30 retrospective patients were also analyzed (mean age 65.7 years, mean follow-up 22.3 months). Among assessed criteria, the most optimal cutoff value for the progression of stenosis was 20 cm/s, at which the sensitivity and specificity were 100% and 91% in prospective group, and were 80% and 93% in retrospective group. In the % difference analysis, prospective group showed sensitivity 100% and specificity 82% in the 20% cutoff. The retrospective group showed sensitivity 80% and specificity 93% in the 15% cutoff. However, results of the regression group were not consistent.

CONCLUSIONS

Diagnosis of progression of MCA stenosis with serial TCD examination is feasible and MFV change of 20 cm/s and % change of 15-20% are suggested as optimal cut-off value but not in the regression. These criteria would be useful for the clinical research and real-world practice.

Magnesium sulfate in combination with nimodipine for the treatment of subarachnoid hemorrhage: a randomized controlled clinical study

Objective Cerebral vasospasm(CVS) after Subarachnoid hemorrhage (SAH) can cause delayed cerebral ischemia,secondary cerebral infarction, and rehemorrhage, which are the leading causes of mutilation and death. Nimodipine has been shown to prevent CVS. Magnesium ion (Mg²⁺) can competitively inhibit the influx of calcium (Ca²⁺) and prevent vasospasm. There is evidence that magnesium sulfate can prevent CVS and reduce infarct volume after SAH. In this study, we evaluated the efficacy and safety of intravenous magnesium sulfate combined with oral nimodipine on CVS, delayed cerebral ischemia, secondary cerebral infarction, and rehemorrhage after SAH. Methods This is a prospective randomized, double-blind trial of 120 patients with SAH who were recruited between January 2003 and January 2009. These patients were assigned to two groups and received the same basic treatment and symptomatic treatment. In group A, patients received 14 days of intravenous administration of 1400 mL 0.9% normal saline + 40 mL 25% magnesium sulfate, 1 mL/min, once per day, followed 7 days of intravenous administration of 500 mL 0.9% normal saline + 15 mL 25% magnesium sulfate, 1 mL/min, once per day and oral nimodipine, 20 mg once, four times a day, for 21 days. Patients in group B received identical treatment to that in group A, except that 25% magnesium sulfate was replaced by placebo. On day 22 of treatment, incidences of intracranial CVS, delayed cerebral ischemia, secondary cerebral infarction, rehemorrhage, neurologic deficits, and death were assessed and adverse events were monitored. Results CVS occurred in 4, 12 patients, lasting for 11.09 ± 5.38, 13.73 ± 6.24 hours, mean velocity (Vm) of 143.2 ± 12.7, 149.6 ± 18.9 cm/s in group A, B; Delayed cerebral ischemia occurred in 3, 10 patients, lasting for 13.16 ± 4.82, 15.57 ± 5.35 hours in group A, B; Secondary cerebral infarction occurred in 2 and 8 patients in groups A and B; Neurologic deficits occurred in3 and 11 patients in groups A and B, All P < 0.05; Rehemorrhage occurred in 4 and 5 patients; Death occurred in 5 and 8 patients in groups A and B, respectively, P >0.05. No obvious adverse events were found in both groups. Conclusion Intravenous magnesium sulfate in combination with oral nimodipine for the treatment of SAH can help reduce the incidences of CVS, delayed cerebral ischemia, secondary cerebral infarction, and neurologic deficits with good safety, but it does not reduce the incidences of rehemorrhage and death.

Early cerebral hemodynamic alternations in patients operated on the first, second and third day after aneurysmal subarachnoid hemorrhage

Surgery timing after aneurysmal subarachnoid hemorrhage (SAH) may influence the risk of vasospasm after early surgical procedure and is correlated with SAH extensiveness. A group consisting of 127 patients with aneurysmal SAH was studied. The changes of mean flow velocity (MFV) were measured in middle cerebral artery (MCA) and in anterior cerebral artery (ACA) by transcranial Doppler sonography (TCD) in three groups of patients divided according to the surgery timing (on the first, second and third day after SAH). Changes of MFV values in MCA and in ACA were similar in all groups. MFV values in the group of patients operated on the third day were the lowest and the pathologic values lasted for the shortest time. In patients with massive SAH (Fisher IV group) and mild SAH (Fisher II group), the lowest MFV values were observed, if patients were operated within 24 hours after SAH. In patients without SAH (Fisher I group), the MFV values were the lowest, if they were operated on the third day after SAH. In patients with severe SAH (Fisher III group), the lowest risk of vasospasm was observed, if they were operated on the second day after SAH; however, the highest risk was found in patients operated on the first day after SAH. Our study suggests: (1) in patients with severe SAH operated on the second day, the lowest risk of vasospasm was observed, and the highest risk of vasospasm was observed if those were operated on the first day; (2) the highest risk of vasospasm was observed in patients operated within 24 hours with mild and massive SAH and in patients without SAH operated on the third day after SAH.

Neuromonitoring in the intensive care unit. I. Intracranial pressure and cerebral blood flow monitoring

BACKGROUND

Monitoring the injured brain is an integral part of the management of severely brain injured patients in intensive care. Brain-specific monitoring techniques enable focused assessment of secondary insults to the brain and may help the intensivist in making appropriate interventions guided by the various monitoring techniques, thereby reducing secondary brain damage following acute brain injury.

DISCUSSION

This review explores methods of monitoring the injured brain in an intensive care unit, including measurement of intracranial pressure and analysis of its waveform, and techniques of cerebral blood flow assessment, including transcranial Doppler ultrasonography, laser Doppler and thermal diffusion flowmetry.

CONCLUSIONS

Various modalities are available to monitor the intracranial pressure and assess cerebral blood flow in the injured brain in intensive care unit. Knowledge of advantages and limitations of the different techniques can improve outcome of patients with acute brain injury.

Neuromonitoring in the intensive care unit. I. Intracranial pressure and cerebral blood flow monitoring

BACKGROUND

Monitoring the injured brain is an integral part of the management of severely brain injured patients in intensive care. Brain-specific monitoring techniques enable focused assessment of secondary insults to the brain and may help the intensivist in making appropriate interventions guided by the various monitoring techniques, thereby reducing secondary brain damage following acute brain injury.

DISCUSSION

This review explores methods of monitoring the injured brain in an intensive care unit, including measurement of intracranial pressure and analysis of its waveform, and techniques of cerebral blood flow assessment, including transcranial Doppler ultrasonography, laser Doppler and thermal diffusion flowmetry.

CONCLUSIONS

Various modalities are available to monitor the intracranial pressure and assess cerebral blood flow in the injured brain in intensive care unit. Knowledge of advantages and limitations of the different techniques can improve outcome of patients with acute brain injury.

The relation between cerebral blood flow velocities as measured by TCD and the incidence of delayed ischemic deficits. A prospective study after subarachnoid hemorrhage

Patients (n = 127) with aneurysmal subarachnoid hemorrhage (SAH) were examined by transcranial Doppler ultrasonography (TCD) in a prospective study to follow the time course of the posthemorrhagic blood flow velocity in both the middle cerebral artery (MCA) and in the anterior cerebral artery (ACA). Results were analysed to reveal their relationship and predictive use with respect to the occurrence of delayed ischemic deficits. Mean flow velocities (MFV) higher than 120 cm sec(-1) in MCA and 90 cm sec(-1) in ACA were interpreted as indicative for significant vasospasm. In 20 of our 127 patients (16%) a delayed ischemic deficit (DID) was subsequently diagnosed clinically (DID+ group). Patients in the DID+ group can be characterized as those individuals who presented early during the observation period post-SAH with highest values of MFV, a faster increase and longer persistence of pathologically elevated MFV-values (exceeding 120 cm sec(-1) in MCA and 90 cm sec(-1) in ACA). They also show a greater difference in MFV-values if one compares the operated to the nonoperated side. Differences in MFV-values obtained in MCA or ACA were statistically significant (p < 0.05) for DID+ and DID- patients. The daily maximal increase of MFV was found between days 9 and 11 after SAH. In the DID+ group, the maximal MFV was 181 +/- 26 cm sec(-1) in MCA and 119 +/- 14 cm sec(-1) in ACA. In contrast to this, patients in the DID- group were found to present with MFV of 138 +/- 11 cm sec(-1) in MCA and 100 +/- 7 cm sec(-1) in ACA respectively. Delayed ischemic deficits appeared three times more often in DID+ patients than in patients with MFV < 120 cm sec(-1), if they showed a MFV > 120 cm sec(-1) in MCA. If pathological values were obtained in ACA, this ratio increases to about four times, if DID + patients presented with MFV > 90 cm sec(-1) versus patients with MFV < 90 cm sec(-1). Daily monitoring of vasospasm using TCD examination is thus helpful to identify patients at high risk for delayed ischemic deficits. This should allow us to implement further preventive treatment regimens.