TRANSCRANIAL DOPPLER (1).pptx
- 1. Dr ASHISH SHARMA SR 1 NEUROLOGY GMC KOTA
- 2. Stethoscope of neurologist Introduced in year 1982 by rune aaslid Initially introduced for detecton of vasospasm of SAH. cheaper,noninvasive,bed side Mark Mohering 2002 M mode doppler Purkayastha S, Sorond F. Transcranial Doppler ultrasound: technique and application. Semin Neurol. 2012 Sep;32(4):411-20. doi: 10.1055/s-0032- 1331812
- 4. American academy of neurology guidelines
- 5. Bathala L, Mehndiratta MM, Sharma VK. Transcranial doppler: Technique and common findings (Part 1). Annals of Indian Academy of Neurology. 2013 Apr;16(2):174.
- 7. TERMS IN TCD PULSALITY INDEX---The difference between PSV and EDV divided by the mean flow velocity (MFV). PI values greater than 1.2 represent high resistance blood flow. PEAK SYSTOLIC VELOCITY --This is the initial peak on each cardiac cycle’s TCD waveform END DIASTOLIC VELOCITY---indicates a low resistance cerebral artery flow pattern in all main intracranial arteries, ranging from 20 to 50% of the PSV MEAN FLOW VELOCITY --calculated as EDV plus one-third of the difference between PSV and EDV RESISTANCE INDEX--The RI is determined by subtracting EDV from PSV and dividing the value by PSV. If the RI value is less than 0.75, it is considered normal. Alexandrov AV, Demchuk AM, Wein TH, Grotta JC. Yield of transcranial Doppler in acute cerebral ischemia. Stroke. 1999 Aug;30(8):1604-9.
- 8. FREQUENTLY USED TERMINOLOGY IN TCD
- 9. PRINCIPALS OF TCD The insonation is performed from the proximal to the distal artery. start closest to the heart and proceed distally located, find and record the best signal inspect at least two locations for each artery Find location where the waveforms exhibit the greatest abnormalities
- 10. USES OF TCD Ischaemic cerebrovascular disease Sickle cell disease Right to left cardiac shunts Intra and extra-cranial arterial steno- occlusive disease Arterio venous malformations and fistulas
- 11. Periprocedural/operative 1. Cerebral thrombolysis in acute stroke 2. Carotid end arterectomy 3. Carotid angioplasty and stenting 4. Post thrombolysis monitoring
- 12. Neurological/Neurosurgical intensive care 1. Vasospasm after SAH 2. Raised ICP 3. Head injury 4. Cerebral circulatory arrest and brain death 5. Intracerebral aneurysm and parenchymal hematoma detection Akif Topcuoglu M. Transcranial Doppler ultrasound in neurovascular diseases: Diagnostic and therapeutic aspects. Journal of neurochemistry. 2012 Nov;123:39-51.
- 13. Intracranial arterial stenosis DX on basis of MFV 50% stenosis ---MCA MFV of >100 and BA MFV of >80 cm/sec 70% stenosis-- >120 and >110cm/sec sensitivity and specificity of TCD for diagnosing stenosis are both around 90%. Sensitivity 74% and specificity 94% when compared to CT Angio.
- 14. Intracranial arterial occlusion No blood flow detectable on direct in sonating the occlusion. The systolic acceleration -lower and diastolic blood flow observed at more- distal sites. waveform is normal at sites that are even more distal the flow velocity is low, at ≤30 cm/sec
- 16. TCD MONITORING SPONTANEOUS EMBOLI Microembollic signals—distal to Large artery occlusion---headframe of TCD. Single MES after 40 min monitoring significant, Characteristic—random during c.s,brief, High intensity ,unidirectional, audible component. Presence of MES on TCD distal to high grade stenosis has higher risk of stroke.
- 18. R------L SHUNT REVERSAL TCD bubble test can detect CV ischemia due to R--L (paradoxical emboli) Technique– 9ml saline plus 1 ml air plus few drops blood—10-15 shakes— injected-----monitoring mca---valsalva for 4 to 6 sec--- RA pressure increased – emboli to LA TCD monitoring is performed for another 16-20 s.
- 20. VASOSPASM occurs 3-12 days after SAH --- delayed ischemic neurological deficits(25%) Performed soon and repeatdely diagnosed when the ratio of the fv between the ICA and MCA (the Lindegaard ratio) is ≥3 and the MCA MFV is >200 cm/sec. diagnosed when the ratio of the VA and BA flow velocities (the modified Lindegaard ratio) is ≥3 and the BA MFV is >85 cm/sec
- 21. MFV <120 cm/s(absent) and >200 cm/s(present) accurate MCA vasospasm systematic review of 26 studies comparing TCD with angiography MFV >120 cm/s was 99% specific and 67% sensitive to angiographic vasospasm of ≥25%. MFV >200 cm/s was 98% specific and 27% sensitive with a positive predictive value (PPV) of 87% for angiographic vasospasm of ≥33% (101 studies review) B. Schatlo and R. M. Pluta, “Clinical applications of transcranial Doppler sonography,” Reviews on Recent Clinical Trials, vol. 2, no. 1, pp. 49–57, 2007.
- 22. TCD IN ACUTE STROKE Prognostication value in acute stroke. Sensitivity 90% in MCA acute occlusion detection Occlusion –6 hrs – in M1 segment detected--- high chance of hemorrhagic transformation Effectiveness ,duration, dose of re canalisation
- 23. TCD sensitivity for ICA and MCA (94 and 93%) terminal VA and BA(56 and 60%). an abrupt increase in TIBI grade or stepwise increase over 30 minutes indicates more complete re canalisation A. M. Demchuk, I. Christou, T. H. Wein et al., “Accuracy and criteria for localizing arterial occlusion with transcranial Doppler,” Journal of Neuroimaging, vol. 10, no. 1, pp. 1–12, 2000
- 24. TCD IN SICKEL CELL DISEASE Stroke mainly occurs in Intracranial ICA proximal MCA. Maximum MFV >200 –requirement for blood transfusion –risk of first ever stroke. Normal: TAMM velocity <170 cm/s — a repeat assessment is indicated ---(conditional)170- 200 repeat TCD in 2 wks--- (Abnormal) 200.
- 25. TCD IN AVM AVM –supplied by high flow shunts with absent vasomotor reactivity easily detected by TCD Sensitivity in detecting middle and large AVM> small (2.5 cm) 2 parameters –velocity and PI AVM (high velocity and low PI) as size increases
- 26. normalization of PI in first few days after intervention while normalization of mean velocity takes 1–3 weeks. Sharma VK, Wong KS. Alexandrov AV. Transcranial Doppler. Front Neurol Neurosci.. 2016;40:124-40.
- 27. TCD IN BRAIN STEM DEATH Criteria for the diagnosis on TCD state that one of the following waveforms must be observed in the BA, B/L ICA, and B/L MCA on two examinations at least 30 minutes apart an oscillating waveform
- 28. small systolic spikes of <200ms duration and <50 cm/s PSV with no diastolic flow Disappearance of intracranial flow with typical signals observed in the extra cranial circulation. J. A. Llompart-Pou, J. M. Abadal, A. Güenther et al., “Transcranial sonography and cerebral circulatory arrest in adults: a comprehensive review,” ISRN Critical Care, vol. 2013,
- 29. J. A. Llompart-Pou, J. M. Abadal, A. Güenther et al., “Transcranial sonography and cerebral circulatory arrest in adults: a comprehensive review,” ISRN Critical Care, vol. 2013, Article ID 167468, 6 pages, 2013.
- 32. REFERENCES Pan Y, Wan W, Xiang M and Guan Y (2022) Transcranial Doppler ultrasonography as a Diagnostic Tool for Cerebrovascular Disorders Front. Hum. Neurosci. 16:841809 Transcranial Doppler Ultrasound: A Review of the Physical Principles and Major Applications in Critical Care (Review Article) Transcranial Doppler: examination techniques and interpretation Youngrok Do1, Yong-Jae Kim2, and Jun Hong Lee3 Role of Transcranial Doppler Ultrasonography in Evaluation of Patients with Cerebrovascular Disease Vijay K. Sharma, MD, Georgios Tsivgoulis, MD, Annabelle Y. Lao, MD, and Andrei V. Alexandrov, MD
- 33. Transcranial doppler: Technique and common findings (Part 1) Lokesh Bathala, Man Mohan Mehndiratta1, Vijay K. Sharma2 Transcranial Doppler Ultrasound: Technique and Application Sushmita Purkayastha, Farzaneh Sorond, MD Role of transcranial Doppler ultrasonography in stroke Sanjukta Sarkar, Sujoy Ghosh, Sandip Kumar Ghosh, Andrew Collier Transcranial Doppler: Techniques and advanced applications: Part 2 Arvind K. Sharma, Lokesh Bathala1, Amit Batra2, Man Mohan Mehndiratta3, Vijay K. Sharma4
Editor's Notes
- #4: (A) indicates ultrasonic probes, with blue arrows indicating TCD and yellow arrows indicating Transcranial color-coded sonography (TCCS). Panels (B–D) show transcranial acoustic windows used in TCD evaluation, including transorbital, suboccipital, and transtemporal windows When a toward-flow signal is detected, the probe is moved to locate the fastest flow and the clearest spectral waveform. The depth is gradually decreased to trace the mid-M1 segment of the MCA at 50 mm, the distal M1 segment at 45 mm, and up to the MCA bifurcation, where the signal disappears at a depth of 30-45 mm. Only segment A1 is inspected since it is difficult to examine segment A2 using TCD. From the ICA bifurcation, the probe is set to a depth of 63 mm and slowly turned 10-30o posteriorly. After an interval with no blood-flow signal, segments P2 and P1 are detected as away- and toward-flow signals, respectively.
- #5: each vessel has a unique depth range, flow direction, and appropriate age-associated flow velocity (FV) Range increase in age, CSF pressure, and central venous pressure lead to the decrease in the FV. While increased blood viscosity results in the elevation in FV. For the TCD scan, the ultrasound transducer is first placed on the temporal bone, over the closed eyelid, and on the base of the skull to capture the signals. TRANS ORBITAL --the Doppler power is reduced to the minimum (17 mW) or 10% of the maximum while examining the transorbital window SUBOCCIPITAL --At a depth of 80-100 mm, the away-flow signal is from the BA. Blood-flow signals should be found and recorded for the proximal (80 mm), mid- (90 mm), and distal (100 mm) BA the probe is placed 2-3 cm left and right of the midline and angled toward the nose. At a depth of 45-80 mm, the away-flow signal is from the VA.
- #9: Normal transcranial Doppler spectral waveform of the middle cerebral artery. The interval from phase 1 to phase 2 is referred to as systolic acceleration, and reflects the resistance from the heart to the artery of interest. The interval from phase 3 to phase 4 is the diastolic phase, and reflects the resistance from the artery of interest to the periphery.
- #14: An increased MFV in the ACA suggests flow diversion, murmur, and microembolic signals (MES) in distal vessels. ACA flow diversion can be detected by an increase in the ACA MFV that is caused by stenosis or hypoplasia in segment A1 of the ACA or a compensatory flow increase in the contralateral MCA due to proximal carotid artery disease.
- #15: Secondary findings suggestive of arterial occlusion include 1) absence or delayed systolic acceleration of the distal artery waveform, 2) development of a collateral circulation, and 3) flow reversal if the left proximal ICA is occluded, the examiner may observe flow reversal in the left OA and left ACA, as well as a lower systolic acceleration in the left MCA.
- #16: Figure 4: (a) abnormal 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
- #19: International Consensus Criteria (ICC) Grade 0: No MES. Grade 1: MES count 1-10. Grade 2: MES count 11-30, and Grade 3: MES count more than 30 with “shower” or “curtain” appearance.
- #23: the prevalence of acute stroke in sickle cell disease is 600 per 100,000 patient –years. TCD screening of children between 2- and 6-years old is recommended on a 6–12 Monthly. If a value >200 cm/s is associated with high risk of stroke in any artery is observed, then blood transfusion is recommended to reduce sickle haemoglobin to less than 30% of total haemoglobin and prevent stroke. (tbf< 170 cm/sec seems to be normal) Stenoocclusive disease, high sensitivity and specificity are demonstrated only in the proximal anterior circulation.
- #27: In embolization, different results may emerge depend on whether the embolization is partial or staged. In first and subsequent stages of staged embolization, there is an increase in the mean velocity of the feeding artery. Thus, it may be due to increase in collateral flow, absence of diameter reduction, or due to recanalization of previously canalized feeders
- #30: This oscillating MCA waveform demonstrates antegrade systolic flow with retrograde diastolic flow, consistent with raised ICP or brain stem death.
- #31: This MCA waveform demonstrates absent diastolic flow and small systolic spikes consistent with the late stages of raised ICP or brain stem death.