Transcranial doppler: Technique and common findings (Part 1)

Lokesh Bathala, Man Mohan Mehndiratta, Vijay K Sharma, Lokesh Bathala, Man Mohan Mehndiratta, Vijay K Sharma

Abstract

Transcranial Doppler (TCD) can be aptly called as the doctor's stethoscope of the brain. Since its introduction in 1982, by Rune Aaslid, TCD has evolved as a diagnostic, monitoring, and therapeutic tool. During evaluation of patients with acute ischemic stroke, TCD combined with cervical duplex ultrasonography provides physiological information on the cerebral hemodynamics, which is often complementary to structural imaging. Currently, TCD is the only diagnostic tool that can provide real time information about cerebral hemodynamics and can detect embolization to the cerebral vessels. TCD is a noninvasive, cost-effective, and bedside tool for obtaining information regarding the collateral flow across various branches of the circle of Willis in patients with cerebrovascular disorders. Advanced applications of TCD help in the detection of right-to-left shunts, vasomotor reactivity, diagnosis, and monitoring of vasospasm in subarachnoid hemorrhage and as a supplementary test for confirmation of brain death. This article describes the basic ultrasound physics pertaining to TCD insonation methods, for detecting the flow in intracranial vessels in addition to the normal and abnormal spectral flow patterns.

Keywords: Ischemic stroke; intracranial stenosis; transcranial doppler.

Conflict of interest statement

Conflict of Interest: Nil.

Figures

Figure 1
Figure 1
(a) Ultrasound probes. Blue arrow - Transcranial Doppler, Yellow arrow - Transcranial color-coded sonography. (b) (ophthalmic), (c) (suboccipital), (d) (temporal) depict various transcranial acoustic windows and probe directions during TCD
Figure 2
Figure 2
PMD screen following a trans-temporal insonation. Upper panel (a) shows the M-mode appearance of various arteries. The red signal up to 65 mm means that the flow is toward the probe (MCA flow) and from 65 mm to 80 mm, away from the probe (ACA flow). Red color beyond 80 mm suggests flow in the contralateral A1 ACA and the blue signal beyond 92 mm represents contralateral MCA. Lower panel (b) shows a normal TCD spectrum at a depth of 47 mm. Note the rapid systolic acceleration and stepwise deceleration during the diastole and significant end-diastolic velocity
Figure 3
Figure 3
Line diagram showing the major intracranial arteries. Flow directions from various arterial segments and depths of insonation in an average human skull are shown. (Adopted with permission from 18reference 17)
Figure 4
Figure 4
(a) bnormal spectral waveforms. Panel A-Note delayed systolic acceleration (blunted flow). Doppler spectra obtained in a patient with moderate (50%) stenosis of right MCA (b) shows elevated flow velocities-MFV >100. Panel (c) shows the flow spectra obtained in a patient with severe (>70%) stenosis of middle cerebral artery. The white arrow shows the flow turbulence (bruit). Spectra with irregular rhythm and flow velocities (d) are diagnostic of atrial fibrillation. Panel e - shows the characteristic alternating flow signals, suggestive of cerebral circulatory arrest

References

    1. Aaslid R, Markwalder TM, Nornes H. Noninvasive transcranial Doppler ultrasound recording of flow velocity in basal cerebral arteries. J Neurosurg. 1982;57:769–74.
    1. Moehring MA, Spencer MP. Power M-mode transcranial Doppler ultrasound and simultaneous single gate spectrogram. Ultrasound Med Biol. 2002;28:49–57.
    1. Martínez-Sánchez P, Serena J, Alexandrov AV, Fuentes B, Fernández-Domínguez J, Díez-Tejedor E. Update on ultrasound techniques for the diagnosis of cerebral ischemia. Cerebrovasc Dis. 2009;27:9–18.
    1. Yeo LL, Sharma VK. Role of transcranial Doppler ultrasonography in cerebrovascular disease. Recent Pat CNS Drug Discov. 2010;5:1–13.
    1. Chernyshev OY, Garami Z, Calleja S, Song J, Campbell MS, Noser EA, et al. Yield and accuracy of urgent combined carotid/transcranial ultrasound testing in acute cerebral ischemia. Stroke. 2005;36:32–7.
    1. Tsivgoulis G, Sharma VK, Lao AY, Malkoff MD, Alexandrov AV. Validation of transcranial Doppler with computed tomography angiography in acute cerebral ischemia. Stroke. 2007;38:1245–9.
    1. Belvís R, Leta RG, Martí-Fàbregas J, Cocho D, Carreras F, Pons-Lladó G, et al. Almost perfect concordance between simultaneous transcranial doppler and transesophageal echocardiography in the quantification of right-to left shunts. J Neuroimaging. 2006;16:133–8.
    1. Lao AY, Sharma VK, Tsivgoulis G, Malkoff MD, Alexandrov AV, Frey JL. Effect of body positioning during transcranial doppler detection of right-to-left shunts. Eur J Neurol. 2007;14:1035–9.
    1. Sharma VK, Tsivgoulis G, Ning C, Teoh HL, Bairaktaris C, Chong VF, et al. Role of multimodal evaluation of cerebral hemodynamics in selecting patients with symptomatic carotid or middle cerebral artery steno-occlusive disease for revascularization. J Vasc Interven Neurol. 2008;1:96–101.
    1. Adams R, McKie V, Nichols F, Carl E, Zhang DL, McKie K, et al. The use of transcranial ultrasonography to predict stroke in sickle cell disease. N Engl J Med. 1992;326:605–10.
    1. Alexandrov AV, Molina CA, Grotta JC, Garami Z, Ford SR, Alvarez-Sabin J, et al. For the CLOTBUST Investigators. Ultrasound-enhanced systemic thrombolysis for acute ischemic stroke. N Engl J Med. 2004;351:2170–8.
    1. Sharma VK, Rathakrishnan R, Ong BK, Chan BP. Ultrasound assisted thrombolysis in acute ischemic stroke: A preliminary experience in Singapore. Ann Acad Med. 2008;37:778–82.
    1. Alexandrov AV, Mikulik R, Ribo M, Sharma VK, Lao AY, Tsivgoulis G, et al. A pilot randomized clinical safety study osonothrombolysis augmentation with ultrasound-activated perflutren-lipid microspheres for acute ischemic stroke. Stroke. 2008;39:1464–9.
    1. Edelman SK. Doppler in Understanding Ultrasound Physics. 3rd ed. Woodlands, Texas: ESP, Inc; 2007. pp. 293–328.
    1. Kremkau FW. Part 1 Sonographic principles in Diagnostic Ultrasound: Principles and Instruments. 7th ed. Philadelphia: Saunders, Elsevier Publications; 2006. pp. 3–155.
    1. Santalucia P, Feldman E. The basic transcranial Doppler examination: Technique and anatomy. In: Babikian VL, Wechsler LR, editors. Transcranial Doppler ultrasonography. 2nd ed. Boston, US: Butterworth Heinemann; 1999. pp. 3–12.
    1. Alexandrov AA. Intracranial cerebrovascular ultrasound examination techniques in Cerebrovascular Ultrasound in Stroke Prevention and Treatment. 2nd ed. USA: Blackwell Publishing; 2011. pp. 13–25.pp. 81–129.
    1. Alexandrov AV, Demchuk AM, Burgin WS. Insonation method and diagnostic flow signatures for transcranial power motion (M-mode) Doppler. J Neuroimaging. 2002;12:236–44.
    1. Alexandrov AV, Sloan MA, Wong LK, Douville C, Razumovsky AY, Koroshetz WJ, et al. Practice standards for transcranial Doppler ultrasound: Part I-test performance. American Society of Neuroimaging Practice Guidelines Committee. J Neuroimaging. 2007;17:11–8.
    1. Feldmann E, Wilterdink JL, Kosinski A, Lynn M, Chimowitz MI, Sarafin J, et al. The stroke outcomes and neuroimaging of intracranial atherosclerosis (SONIA) trial. Neurology. 2007;68:2099–106.
    1. Zhao L, Barlinn K, Sharma VK, Tsivgoulis G, Cava LF, Vasdekis SN, et al. Velocity criteria for intracranial stenosis revisited: An international multicenter study of transcranial Doppler and digital subtraction angiography. Stroke. 2011;42:3429–34.

Source: PubMed

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