A randomized trial of nicardipine in subarachnoid hemorrhage: angiographic and transcranial Doppler ultrasound results

1993 ◽  
Vol 78 (4) ◽  
pp. 548-553 ◽  
Author(s):  
E. Clarke Haley ◽  
Neal F. Kassell ◽  
James C. Torner ◽  
_ _
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Doppler Ultrasound ◽  
Transcranial Doppler ◽  
Transcranial Doppler Ultrasound ◽  
High Dose ◽  
Content Type ◽  
Central Registry ◽  
Significant Difference ◽  
Fine Print ◽  
Flow Velocities

✓ Calcium antagonist drugs were proposed for use in patients with recent aneurysmal subarachnoid hemorrhage (SAH) because of their ability to block the effects of a wide variety of vasoconstrictor substances on cerebral arteries in vitro. It was suggested that these agents might, therefore, be useful in ameliorating cerebral vasospasm and its ischemic consequences which frequently complicate SAH. This hypothesis was tested in an arm of a randomized double-blind placebo-controlled trial of high-dose intravenous nicardipine in patients with recently ruptured aneurysms. Participating investigators were required to send selected copies of all admission and follow-up angiograms obtained between Days 7 and 11 following hemorrhage (the peak period of risk for vasospasm) to the Central Registry of the Cooperative Aneurysm Study for blinded interpretation and review for the presence and severity of angiographic vasospasm. In centers with transcranial Doppler ultrasound (TCD) capabilities, middle cerebral artery (MCA) mean flow velocities were measured and recorded. Angiograms obtained between Days 7 and 11 were available for 103 (23%) of 449 patients receiving nicardipine and 121 (26%) of 457 receiving placebo. There was a balance of prognostic factors for vasospasm between the groups. Fifty-one percent of placebo-treated patients had moderate or severe vasospasm on “Day 7–11 angiograms” compared to 33% of nicardipine-treated patients. This difference is statistically significant (p < 0.01). Sixty-seven (49%) of 137 placebo-treated patients examined with TCD between Days 7 and 11 had mean MCA flow velocities exceeding 120 cm/sec compared to 26 (23%) of 112 nicardipine-treated patients (significant difference, p < 0.001). These data suggest that high-dose intravenous nicardipine reduces the incidence and severity of delayed cerebral arterial narrowing in patients following aneurysmal SAH.

Transcranial Doppler ultrasound studies of cerebral autoregulation and subarachnoid hemorrhage in the rabbit

1990 ◽  
Vol 73 (4) ◽  
pp. 601-610 ◽  
Author(s):  
Richard J. Nelson ◽  
Sheila Perry ◽  
Tony K. Hames ◽  
John D. Pickard
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Flow Velocity ◽  
Doppler Ultrasound ◽  
Transcranial Doppler ◽  
Cerebral Autoregulation ◽  
Time Course ◽  
Cerebrovascular Reactivity ◽  
Waveform Analysis ◽  
Content Type ◽  
Fine Print

✓ The authors describe a method for Doppler ultrasound recording of flow velocity in the basilar artery of normal rabbits and rabbits with experimental subarachnoid hemorrhage (SAH). With this transcranial Doppler (TCD) model, clinical assumptions regarding flow velocity/cerebral blood flow (CBF) relationships, autoregulatory responses, and Doppler spectral waveform analysis can be tested under controlled conditions and compared with established methods of CBF measurement (hydrogen clearance). The time course of changes in flow velocity following SAH (cerebral vasospasm) is successfully demonstrated using the experimental TCD method. There are significant differences in the flow velocity and CBF responses to hypercapnia, hypocapnia, and trimethaphan-induced hypotension which indicate that TCD cannot be considered a simple alternative to CBF measurement for the study of cerebrovascular reactivity and cerebral autoregulation.

CO2 reactivity in arteriovenous malformations of the brain: a transcranial Doppler ultrasound study

1994 ◽  
Vol 80 (4) ◽  
pp. 624-630 ◽  
Author(s):  
Antônio A F. De Salles ◽  
Iñaki Manchola
Keyword(s):  
Carbon Dioxide ◽  
Doppler Ultrasound ◽  
Transcranial Doppler ◽  
Arteriovenous Malformations ◽  
Transcranial Doppler Ultrasound ◽  
Content Type ◽  
Control Subjects ◽  
Feeding Vessels ◽  
Carbon Dioxide Reactivity ◽  
Fine Print

✓ Arteriovenous malformations (AVM's) are congenital tangles of vessels that have a high blood flow through a low-resistance nidus. The vessels in the nidus may lack normal vasoreactivity in response to changes in PaCO2 or perfusion pressure (autoregulation). Arteriovenous malformation hemodynamics have been assessed based on the response of AVM feeding arteries to hypocapnia. Twenty-five AVM patients, aged 34 ± 11 years (mean ± standard deviation), were admitted to the Massachusetts General Hospital for proton-beam radiation therapy. Fourteen healthy volunteers aged 30 ± 7 years served as control subjects. Angiograms with calibrated markers permitting magnification correction were available for all patients. The limits of the middle cerebral artery, as determined by transcranial Doppler ultrasonography, were compared to measurements made on the angiograms. Hyperventilation was induced at a rate set by a metronome. Fixed bilateral Doppler probes allowed almost simultaneous sampling of two vessels. Volunteer control subjects were hyperventilated in two steps. The two PaCO2 step decreases were significant (mean resting PaCO2 40.6 ± 3.5 mm Hg, Step 1 level 29.4 ± 3.5 mm Hg and Step 2 level 23.8 ± 3.5 mm Hg; p < 0.01). These decreases induced a significant decrease in mean flow velocity (Vm) and an increase in the pulsatility index (p < 0.001). Mean carbon dioxide reactivity (%ΔVm/ΔPaCO2) was 2.74 ± 1.0 for Step 1 and 1.44 ± 1.8 for Step 2 (p < 0.003). The mean PaCO2 decrease in patients was from 39.5 ± 4.0 mm Hg to 27.0 ± 3.5 mm Hg. Carbon dioxide reactivity was 0.92 ± 1.12 for feeding vessels and 2.59 ± 1.78 for nonfeeding vessels (p < 0.001). Transcranial Doppler ultrasound and angiographic depth measurements correlated well. Hyperventilation induced significantly more hemodynamic changes in control and nonfeeding middle cerebral arteries than in feeding vessels. Impaired CO2 reactivity may help to identify AVM feeding vessels as well as the relative magnitude of the flow provided to the malformation.

Posttraumatic cerebral arterial spasm: transcranial Doppler ultrasound, cerebral blood flow, and angiographic findings

1992 ◽  
Vol 77 (4) ◽  
pp. 575-583 ◽  
Author(s):  
Neil A. Martin ◽  
Curtis Doberstein ◽  
Cynthia Zane ◽  
Michael J. Caron ◽  
Kathleen Thomas ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Doppler Ultrasound ◽  
Transcranial Doppler ◽  
Transcranial Doppler Ultrasound ◽  
Arterial Spasm ◽  
Content Type ◽  
Closed Head ◽  
Extracranial Ica ◽  
Fine Print

✓ Thirty patients admitted after suffering closed head injuries, with Glasgow Coma Scale scores ranging from 3 to 15, were evaluated with transcranial Doppler ultrasound monitoring. Blood flow velocity was determined in the middle cerebral artery (MCA) and the intracranial portion of the internal carotid artery (ICA) in all patients. Because proximal flow in the extracranial ICA declines in velocity when arterial narrowing becomes hemodynamically significant, the extracranial ICA velocity was concurrently monitored in 19 patients. To assess cerebral perfusion, cerebral blood flow (CBF) measurements obtained with the intravenous 113Xe technique were completed in 16 patients. Vasospasm, designated as MCA velocity exceeding 120 cm/sec, was found in eight patients (26.7%). Severe vasospasm, defined as MCA velocity greater than 200 cm/sec, occurred in three patients, and was confirmed by angiography in all three. Subarachnoid hemorrhage (SAH) was documented by computerized tomography in five (62.5%) of the eight patients with vasospasm. All cases of severe vasospasm were associated with subarachnoid blood. The time course of vasospasm in patients with traumatic SAH was similar to that found in patients with aneurysmal SAH; in contrast, arterial spasm not associated with SAH demonstrated an uncharacteristically short duration (mean 1.25 days), suggesting that this may be a different type of spasm. A significant correlation (p < 0.05) was identified between the lowest CBF and highest MCA velocity in patients during the period of vasospasm, indicating that arterial narrowing can lead to impaired CBF. Ischemic brain damage was found in one patient who had evidence of cerebral infarction in the territories supplied by the arteries affected by spasm. These findings demonstrate that delayed cerebral arterial spasm is a frequent complication of closed head injury and that the severity of spasm is, in some cases, comparable to that seen in aneurysmal SAH. This experience suggests that vasospasm is an important secondary posttraumatic insult that is potentially treatable.

Validation of transcranial Doppler ultrasound with a stereotactic neurosurgical technique

1995 ◽  
Vol 82 (6) ◽  
pp. 972-975 ◽  
Author(s):  
Lee H. Monsein ◽  
Alex Y. Razumovsky ◽  
Stacey J. Ackerman ◽  
Haring J. W. Nauta ◽  
Daniel F. Hanley
Keyword(s):  
Cerebral Artery ◽  
Transcranial Doppler ◽  
Anterior Cerebral Artery ◽  
Transcranial Doppler Ultrasound ◽  
Content Type ◽  
Stereotactic Technique ◽  
Significant Difference ◽  
Neurosurgical Technique ◽  
The Individual ◽  
Fine Print

✓ Vessel identification during a transcranial Doppler (TCD) ultrasound examination is usually based on well-established inferential criteria without confirmation by imaging. Part of a routine study involves taking measurements from the M1 segment of the middle cerebral artery (MCA) and the A1 segment of the anterior cerebral artery (ACA) at the points of maximum mean linear blood flow velocity (LBFV). The authors tested the hypothesis that insonation is from the midpoints of the M1 and A1 segments during clinical TCD examinations. Conventional hand-held TCD examinations were performed on five volunteers. The points of maximum mean LBFV of the M1 and A1 segments of the MCA and ACA were located. Measurements were also taken from the midpoints of the M1 and A1 segments using a magnetic resonance (MR) imaging-guided stereotactic TCD technique. Values for depths of insonation and maximum mean LBFV obtained with the two techniques were compared. There was no significant difference between the two techniques for the measured values of depth of insonation of either the individual vessels (p > 0.11) or the aggregate (p = 0.46). There was a significant difference between the aggregate maximum mean LBFV measurements (p = 0.0022). The hand-held technique systematically produced higher maximum mean LBFV than the MR-guided stereotactic technique. The authors conclude that when using traditional criteria for TCD examination of the ACA and MCA, the points of insonation approximate the middle of the A1 and M1 segments.

Transcranial Doppler ultrasound study of the effects of nitrous oxide on cerebral autoregulation during neurosurgical anesthesia: a randomized controlled trial

2003 ◽  
Vol 99 (1) ◽  
pp. 58-64 ◽  
Author(s):  
Domenico G. Iacopino ◽  
Alfredo Conti ◽  
Calogero Battaglia ◽  
Clotilde Siliotti ◽  
Tullio Lucanto ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Doppler Ultrasound ◽  
Transcranial Doppler ◽  
Transcranial Doppler Ultrasound ◽  
Gas Mixture ◽  
Sevoflurane Anesthesia ◽  
Content Type ◽  
Randomized Controlled ◽  
Hyperemic Response ◽  
Fine Print

Object. Nitrous oxide has an adverse effect on cerebrovascular hemodynamics. Increased intracranial pressure, cerebral blood flow (CBF), cerebral metabolic rate of O2 (CMRO2), and reduced autoregulation indices have been reported, but their magnitudes are still being debated. This study was designed to evaluate the effect of N2O on CBF and autoregulatory indexes during N2O—sevoflurane anesthesia in a prospective randomized controlled series of patients. Methods. Two groups of 20 patients were studied on the basis of the use of N2O in the anesthetic gas mixture. The transient hyperemic response test, which relies on transcranial Doppler ultrasound techniques, was used to assess cerebral hemodynamics. The time-averaged mean flow velocity, considered to be an index of actual CBF, increased significantly (p < 0.001) after introduction of N2O. The hyperemic response, considered as the index of autoregulatory potential, decreased significantly after introduction of N2O into the gas mixture (p < 0.001). Conclusions. The increase in CBF and the reduction in autoregulatory indices suggest caution in using N2O during sevoflurane anesthesia, especially in patients with reduced autoregulatory reserve and during neurosurgical interventions. Transcranial Doppler ultrasonography is an efficacious method to evaluate the effects of anesthetic agents on CBF.

Cerebral hemodynamic impairment after aneurysmal subarachnoid hemorrhage as evaluated using transcranial Doppler ultrasonography: relationship to delayed cerebral ischemia and clinical outcome

2001 ◽  
Vol 95 (3) ◽  
pp. 393-401 ◽  
Author(s):  
Tõnu Rätsep ◽  
Toomas Asser
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Cerebral Ischemia ◽  
Clinical Outcome ◽  
Transcranial Doppler ◽  
Aneurysmal Subarachnoid Hemorrhage ◽  
Delayed Cerebral Ischemia ◽  
Content Type ◽  
Unfavorable Clinical Outcome ◽  
Hemodynamic Impairment ◽  
Fine Print

Object. In this study the authors evaluated the relative role of cerebral hemodynamic impairment (HDI) in the pathogenesis of delayed cerebral ischemia and poor clinical outcome after aneurysmal subarachnoid hemorrhage (SAH). Methods. Cerebral hemodynamics were assessed daily with transcranial Doppler (TCD) ultrasonography in 55 consecutive patients with verified SAH. Hemodynamic impairment was defined as blood flow velocity (BFV) values consistent with vasospasm in conjunction with impaired autoregulatory vasodilation as evaluated using the transient hyperemic response tests in the middle cerebral arteries. A total of 1344 TCD examinations were performed, in which the evaluation of HDI was feasible during 80.9% and HDI was registered during 12% of the examinations. It was found that HDI occurred in 60% of patients and was frequently recorded in conjunction with severe vasospasm (p < 0.05) and a rapid increase of BFV values (p < 0.05). Detection of HDI was closely associated with the development of delayed ischemic brain damage after SAH (p < 0.05). Furthermore, because delayed ischemia was never observed in cases in which vasospasm had not led to the development of HDI, its occurrence increased significantly the likelihood of subsequent cerebral ischemia among the patients with vasospasm (p < 0.05). Detection of HDI was independently related to unfavorable clinical outcome according to Glasgow Outcome Scale at 6 months after SAH (p < 0.05). Conclusions. The results showed that HDI is common after SAH and can be evaluated with TCD ultrasonography in routine clinical practice. Detection of HDI could be useful for identifying patients at high or low risk for delayed ischemic complications and unfavorable clinical outcome after SAH.

Is routine transcranial Doppler ultrasound monitoring useful in the management of subarachnoid hemorrhage?

1998 ◽  
Vol 88 (2) ◽  
pp. 272-276 ◽  
Author(s):  
Joanna M. Wardlaw ◽  
Ruth Offin ◽  
Graham M. Teasdale ◽  
Evelyn M. Teasdale
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Neurological Deficit ◽  
Transcranial Doppler ◽  
Controlled Trial ◽  
Positive Contribution ◽  
Content Type ◽  
Delayed Ischemic Neurological Deficit ◽  
Ultrasound Monitoring ◽  
The Impact ◽  
Fine Print

Object. In this prospective observational study, the authors assess the impact of routine transcranial Doppler (TCD) ultrasound monitoring on the diagnosis, management, and outcome of delayed ischemic neurological deficit complicating subarachnoid hemorrhage (SAH). Methods. Over a 10-month period 186 patients admitted to a regional neurosciences center were included in the study. Three times a week, routine TCD examinations performed by neuroradiographers made an important positive contribution to the diagnosis of delayed ischemic neurological deficit in 72% of patients with this complication and led to altered management for the benefit of the patient in 43%. In 9% of patients with recent SAH, it was believed that the outcome might have been better if the TCD result had been acted upon appropriately. The TCD results did not adversely influence management or outcome and were generally accurate when compared with those obtained on angiography. Conclusions. A routine TCD service provided by neuroradiographers is accurate and useful in diagnosing and managing elevated blood velocities and ischemic neurological deficit following SAH. In addition, it is possible that if the information gleaned from TCD findings was used more often in patient management, outcome might be improved; however, a randomized controlled trial is necessary to assess both these points definitively.

Medulloblastoma: freedom from relapse longer than 8 years — a therapeutic cure?

1991 ◽  
Vol 75 (4) ◽  
pp. 575-582 ◽  
Author(s):  
Mark G. Belza ◽  
Sarah S. Donaldson ◽  
Gary K. Steinberg ◽  
Richard S. Cox ◽  
Philip H. Cogen
Keyword(s):  
Medical Center ◽  
Survival Rates ◽  
Adjunctive Treatment ◽  
High Dose ◽  
Content Type ◽  
Significant Difference ◽  
Long Term Follow Up ◽  
Fine Print

✓ Seventy-seven patients presenting with medulloblastoma between 1958 and 1986 were treated at Stanford University Medical Center and studied retrospectively. Multimodality therapy utilized surgical extirpation followed by megavoltage irradiation. In 15 cases chemotherapy was used as adjunctive treatment. The 10- and 15-year actuarial survival rates were both 41% with an 18-year maximum follow-up period (median 4.75 years). There were no treatment failures after 8 years of tumor-free survival. Gross total removal of tumor was achieved in 22 patients (32%); the surgical mortality rate was 3.9%. No significant difference was noted in the incidence of metastatic disease between shunted and nonshunted patients. The classical form of medulloblastoma was present in 67% of cases while the desmoplastic subtype was found in 16%. Survival rates were best for patients presenting after 1970, for those with desmoplastic tumors, and for patients receiving high-dose irradiation (≥ 5000 cGy) to the posterior fossa. Although early data on freedom from relapse suggested a possible beneficial effect from chemotherapy, long-term follow-up results showed no advantage from this modality of treatment. The patterns of relapse and survival were examined; 64% of relapses occurred within the central nervous system, and Collins' rule was applicable in 83% of cases beyond the period of risk. Although patients treated for recurrent disease could be palliated, none were long-term survivors. The study data indicate that freedom from relapse beyond 8 years from diagnosis can be considered as a cure in this disease. Long-term follow-up monitoring is essential to determine efficacy of treatment and to assess survival patterns accurately.

The effect of interleukin-2 on the blood-brain barrier in the 9L gliosarcoma rat model

1989 ◽  
Vol 70 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Joseph T. Alexander ◽  
Stephen C. Saris ◽  
Edward H. Oldfield
Keyword(s):  
Blood Brain Barrier ◽  
Interleukin 2 ◽  
Brain Barrier ◽  
High Dose ◽  
Normal Brain ◽  
Content Type ◽  
Tumor Bearing ◽  
Blood Brain ◽  
Significant Difference ◽  
Fine Print

✓ Carbon-14-labeled aminoisobutyric acid was used to determine local blood-to-tissue transfer constants in 22 Fischer rats with intracerebral 9L gliosarcomas that received either high-dose parenteral interleukin-2 (IL-2) or a control injection. In tumor and peritumoral tissue, the transfer constants in the IL-2-treated animals (89.6 ± 14.6 and 35.8 ± 6.0, respectively, mean ± standard error of the mean) were larger (p < 0.05) than in control animals (61.4 ± 6.4 and 14.6 ± 2.2, respectively). In contrast, in normal frontal and occipital tissue contralateral to the tumor-bearing hemisphere, there was no significant difference between the transfer constants in IL-2-treated and control animals. Furthermore, treatment of animals with IL-2 excipient caused no change in permeability as compared to animals treated with Hanks' balanced salt solution. Parenteral injection of IL-2 increases blood-brain barrier disruption in tumor-bearing rat brain but does not increase the vascular permeability of normal brain. Methods to prevent this increased tumor vessel permeability are required before parenteral IL-2 can be used safely for the treatment of primary or metastatic brain tumors.

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