Transcranial Doppler is routinely used to assess the cerebrovascular reactivity, despite scarce information on its reproducibility. We evaluated the reproducibility of cerebrovascular reactivity measurements by this method utilizing different vasodilatory and vasoconstrictor stimuli. The cerebrovascular reactivity was measured in 45 healthy volunteers during hypercapnia induced by inhalation of a mixture of 5% CO2 and 95% O2, breath holding and rebreathing, and during hypocapnia induced by voluntary hyperventilation. Three sets of measurements were performed at times 0, 1, and 24 h to assess the within-observer short- and long-term reproducibility. The reproducibility was analyzed using the intraclass correlation coefficient. For the CO2 inhalation method, a good short-term (rI = 0.55; 95% CI = 0.39–0.68) and a good long-term (rI = 0.43; 95% CI = 0.25–0.59) reproducibility was found. For the breath-holding method a good short-term agreement was found (rI = 0.41; 95% CI = 0.22–0.57), while the long-term reproducibility was poor (rI = 0.17; 95% CI = –0.03–0.36). Rebreathing showed a fair (rI = 0.31; 95% CI = 0.11–0.48) short-term and a poor (rI = 0.17; 95% CI = –0.03–0.36) long-term reproducibility. For voluntary hyperventilation, the short-term reproducibility was good (rI = 0.53; 95% CI = 0.36–0.66), and the long- term reproducibility was fair (rI = 0.31; 95% CI = 0.11–0.48). In our study, CO2 inhalation and voluntary hyperventilation had the highest reproducibility and should be preferred when assessing cerebral vasoreactivity, especially in follow-up studies.

Bishop CCR, Powel S, Insall M, Rutt D, Browse NL: Effect of internal carotid artery occlusion on middle cerebral artery blood at rest and in response to hypercapnia. Lancet 1986;i:710–712.
Ringelstein EB, Sievers C, Ecker S, Schneider PA, Otis SM: Noninvasive assessment of CO2-induced cerebral vasomotor response in normal individuals and patients with internal carotid artery occlusions. Stroke 1988;19:963–969.
Kleiser B, Widder B: Course of carotid artery occlusions with impaired cerebrovascular reactivity. Stroke 1992;23:171–174.
Widder B, Kleiser B, Krapf H: Course of cerebrovascular reactivity in patients with carotid artery occlusions. Stroke 1994;25:1963–1967.
Fürst H, Hartl WH, Janssen I: Patterns of cerebrovascular reactivity in patients with unilateral asymptomatic carotid artery stenosis. Stroke 1994;25:1193–1200.
Müller M, Schimrigk K: Vasomotor reactivity and pattern of collateral blood flow in severe occlusive carotid artery disease. Stroke 1996;27:296–299.
Klijn CJM, Kappelle LJ, Tulleken CAF, van Gijn J: Symptomatic carotid artery occlusion: A reappraisal of hemodynamic factors. Stroke 1997;28:2084–2093.
Baumgartner RW, Regard M: Role of impaired CO2 reactivity in the diagnosis of cerebral low flow infarcts. J Neurol Neurosurg Psychiatry 1994;57:814–817.
Maeda H, Matsumoto M, Handa N, Hougaku H, Ogawa S, Itoh T, Tsukamoto Y, Kamada T: Reactivity of cerebral blood flow to carbon dioxide in various types of ischemic cerebrovascular disease: Evaluation by the transcranial Doppler method. Stroke 1993;24:670–675.
Aaslid R, Markwalder TM, Nornes H: Noninvasive transcranial Doppler ultrasound recording of flow velocity in basal arteries. J Neurosurg 1982;57:769–774.
Totaro R, Marini C, Cannarsa C, Prencipe M: Reproducibility of transcranial Doppler sonography: A validation study. Ultrasound Med Biol 1992;18:173–177.
Ratnatunga C, Adiseshiah M: Increase in middle cerebral artery velocity on breath holding: A simplified test of cerebral perfusion reserve. Eur J Vasc Surg 1990;4:519–523.
Markus HS, Harrison MJG: Estimation of cerebrovascular reactivity using transcranial Doppler, including the use of breath-holding as the vasodilatory stimulus. Stroke 1992;23:668–673.
Dahl A, Russell D, Rootwelt K, Nyberg-Hansen R, Kerty E: Cerebral vasoreactivity assessed with transcranial Doppler and regional cerebral blood flow measurements: Dose, serum concentration, and time course of the response to acetazolamide. Stroke 1995;26:2302–2306.
Ameriso SF, Mohler JG, Suarez M, Fisher M: Morning reduction of cerebral vasomotor reactivity. Neurology 1994;44:1907–1909.
Fleiss JL: The Design and Analysis of Clinical Experiments. New York, Wiley, 1986.
Landis JR, Koch GG: The measurement of observer agreement for categorial data. Biometrics 1977;33:159–174.
Bland JM, Altman DG: Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986;i:307–310.
Totaro R, Marini C, De Matteis G, Di Napoli M, Carolei A: Cerebrovascular reactivity in migraine during headache-free intervals. Cephalalgia 1997;17:191–194.
Stoll M, Treib J, Hamann G, Jost V, Argyropulu RBO, Haass A: Comparison of different TCD tests: Assessment of the cerebrovascular reserve capacity. Ultraschall Med 1994;15:243–247.
Widder B: Use of breath holding for evaluating cerebrovascular reserve capacity. Stroke 1992;23:1680.
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.