TRANSCRANIAL DOPPLER AND ITS APPLICATION IN NEUROLOGY

TRANSCRANIAL DOPPLER AND ITS APPLICATION IN NEUROLOGY

1. TRANSCRANIAL DOPPLER 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

3. American academy of neurology guidelines

4. 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.

5. 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 .

6. FREQUENTLY USED TERMINOLOGY IN TCD

7. 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

8. 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

9. Periprocedural /operative Cerebral thrombolysis in acute stroke Carotid end arterectomy Carotid angioplasty and stenting Post thrombolysis monitoring

10. Neurological/Neurosurgical intensive care Vasospasm after SAH Raised ICP Head injury Cerebral circulatory arrest and brain death 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.

11. 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 .

12. 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

13. 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 .

14. 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.

15. 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

16. 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.

17. 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

18. 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

19. 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.

20. 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

21. 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 .

22. 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

23. 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,

24. 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.

25. REFERENCES Pan Y, Wan W, Xiang M and Guan Y (2022) Transcranial Doppler u ltrasonography 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

26. 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