Carotid duplex ultrasound Jenelle (General Ultrasound Department) Anatomy Normal Carotid Ultrasound Todd (Vascular Ultrasound Department-Coordinator) Abnormal Carotid Ultrasound Live Scanning Demonstration by Todd Practice time – grab a partner!

Carotid duplex ultrasound Jenelle Beadle March, 2015

Objectives Anatomy Carotid Duplex Ultrasound Tips/Pitfalls Classic Variants Carotid Duplex Ultrasound Indications Position/Technique Required Images Normal spectral analysis Tips/Pitfalls

Anatomy

Cerebrovascular System supplies the head Carotid Duplex Ultrasound exams the extracranial portion of the cerebrovascular system

Extracranial Cerebrovascular System Innominate/brachiocephalic Subclavian Vertebral Common Carotid (CCA) Internal Carotid (ICA) External Carotid (ECA) http://www.slideshare.net/shaffar75/doppler-ultrasound-of-carotid-arteries

Innominate/brachiocephalic (Rt sided only) Originate: Aortic Arch (1st) Terminate: Rt CCA / Rt Subclavian

Subclavian Arteries Originate: Rt – Innominate Lt – Aortic Arch (3rd) Branches: Vertebral Terminate: Axillary

Vertebral Arteries Originate: Subclavian

Vertebral Arteries Originate: Subclavian Pass through transverse foramena C6 Atlas (C1) Terminate: join to form basilar (intracranial)

Common Carotid Arteries (CCA) Originate: Rt – Innominate Lt – Aortic Arch (2nd) Terminate: ICA/ECA

External Carotid Arteries (ECA) Originate: CCA

External Carotid Arteries (ECA) Branches: numerous 1st: Superior Thyroid Terminate: Superficial Temporal / Maxillary

Internal Carotid Arteries (ICA) Originate: CCA

NO extracranial branches

Internal Carotid Arteries (ICA) Originate: CCA Branches: Intracranial only

Internal Carotid Arteries (ICA) Originate: CCA Branches: Intracranial only Terminate: Circle of Willis Anterior & middle cerebral arteries

Innominate/Brachiocephalic

Rt Subclavian Innominate/Brachiocephalic

Rt Vertebral Rt Subclavian Innominate/Brachiocephalic

Rt CCA Rt Vertebral Rt Subclavian Innominate/Brachiocephalic

Rt ICA Rt CCA Rt Vertebral Rt Subclavian Innominate/Brachiocephalic

Lt Vertebral Rt ICA Rt CCA Rt Vertebral Rt Subclavian Innominate/Brachiocephalic

Lt Vertebral Rt ICA Lt ICA Rt CCA Rt Vertebral Rt Subclavian Innominate/Brachiocephalic

Lt Vertebral Rt ICA Lt ICA Lt ECA Rt CCA Rt Vertebral Rt Subclavian Innominate/Brachiocephalic

Lt Vertebral Rt ICA Lt ICA Lt ECA Rt CCA Lt CCA Rt Vertebral Rt Subclavian Innominate/Brachiocephalic

Lt Vertebral Rt ICA Lt ICA Lt ECA Rt CCA Lt CCA Rt Vertebral Lt Subclavian Rt Subclavian Innominate/Brachiocephalic

Lt Vertebral Rt ICA Lt ICA Lt ECA Rt CCA Lt CCA Rt Vertebral Lt Subclavian Rt Subclavian Innominate/Brachiocephalic Aortic Arch

Anatomical variants

Numerous anatomical variants involving the aortic arch branches

3 Branches: Innominate, Lt CCA, Lt Subclavian CLASSIC (85%) 3 Branches: Innominate, Lt CCA, Lt Subclavian Classic 85% Bovine 10% VARIANTS Bovine Arch (10%) Left vertebral arises from aortic arch (3%) Aberrant right subclavian artery (2%) Lt Vert 3% Aberrant Rt SCl 2% *All other aortic arch variants combined (<1%)

Bovine arch (10%) Most common aortic arch branching variant 1st and 2nd aortic arch branches combined into one Normal: 3 separate aortic arch branches Bovine Arch: common origin for Innominate and Left CCA

Bovine arch (10%) Most common aortic arch branching variant 1st and 2nd aortic arch branches combined into one Bovine Arch: common origin for Innominate and Left CCA

Bovine arch Type 2 Normal: 3 separate aortic arch branches Bovine Arch: Left CCA originates from Innominate

“Bovine” arch Misnomer: Erroneous reference to cow’s anatomy Actual cow anatomy consists of a single trunk branch off the aortic arch

LEFT VERTEBRAL – 3RD branch(3%) Left subclavian: 4th branch

Aberrant right subclavian (2%) Right subclavian: 4th branch Right CCA: 1st branch No innominate Rt CCA arises directly from the arch (1st), rather than innominate – this angiogram shows a shared CCA trunk; Rt subclav arises directly from the arch (4th); coarse varies - 80% posterior to esophagus

ICA tortuosity variants Course variations are common http://www.slideshare.net/shaffar75/doppler-ultrasound-of-carotid-arteries

ICA tortuosity variants Course variations are common http://www.slideshare.net/shaffar75/doppler-ultrasound-of-carotid-arteries

ICA/ECA origin variants Variations in origin of the ECA & ICA are uncommon

Vertebral Artery Course variants C6 (93%) – most common C5 (5%) – 2nd most common

Carotid duplex ultrasound

indications Cerebrovascular Accident (CVA) Transient Ischemic Attacks (TIA) Cervical Bruit Pulsatile Mass Less Specific Symptoms Dizziness Headaches Pre-operative Post-operative Monitor known carotid arterial disease

Position/technique Patient Position Supine Head angled to the side Rolled towel under neck Position adjusted to optimize sonographic window

Position/technique Patient Position Supine Head angled to the side Rolled towel under neck Position adjusted to optimize sonographic window Technique Highest frequency, penetrating transducer Keep angle at 60 degrees Diagnostic Criteria Reproducibility 3-5 cycles/waveform Waveform 2/3 of image Lower baseline Decrease scale

Exam protocol Protocol will be available on Sharepoint Written and Image formats Protocol still needs to be approved to be made official

Exam protocol Protocol will be available on Sharepoint Written and Image formats Protocol still needs to be approved to be made official Scan Assistant protocol has been set up in accordance with written protocol Protocol will also be set up on Siemens machine at SH

Exam protocol Protocol will be available on Sharepoint Written and Image formats Protocol still needs to be approved to be made official Scan Assistant protocol has been set up in accordance with written protocol Protocol will also be set up on Siemens machine at SH Examine all accessible portions of the CCA/ICA Basic assessment of the ECA/Vert/Subcl

Exam protocol Protocol will be available on Sharepoint Written and Image formats Protocol still needs to be approved to be made official Scan Assistant protocol has been set up in accordance with written protocol Protocol will also be set up on Siemens machine at SH Examine all accessible portions of the CCA/ICA Basic assessment of the ECA/Vert/Subcl Protocol is designed to be the minimal required images Additional images will often be necessary when the exam is normal Additional images will always be necessary when pathology is encountered

*Image at the most proximal, straight segment CCA Proximal Trans

CCA Proximal Long

CCA Proximal Color Doppler

CCA Proximal Spectral Doppler

*2-3cm below the bifurcation CCA Distal Trans Transducer: 6-15MHz

CCA Distal Long

CCA Distal Color Doppler

CCA Distal Spectral Doppler

CCA Spectral Analysis: EDV should be above zero EDV should be similar to the contralateral CCA, taken at approximately the same level

Bifurcation Trans (bulb)

Bifurcation Trans (just above bulb)

*Look for branches ECA Prox Long

ECA Prox Color Doppler

ECA Prox Spectral Doppler

ECA Spectral Analysis Higher resistance than the ICA PSV normally greater ICA Sharp upstroke Prominent dicrotic notch (may reverse) EDV approach/reach zero

*Include bulb ICA Prox Long

*Obtained just below the bulb where vessel is no longer dilated ICA Prox Color Doppler

*Waveform may reflect flow disturbances of the bulb extending into the prox ICA ICA Prox Spectral Doppler

ICA Mid Color Doppler

ICA Mid Spectral Doppler

ICA Dist Color Doppler

ICA Dist Spectral Doppler

ICA Spectral Analysis Low resistance Continuous forward flow EDV well above zero

Vertebral Color Doppler

Vertebral Spectral Doppler

Vertebral Spectral Analysis Low resistance Slightly more resistive than the ICA Antegrade, bidirectional, retrograde

*Sampled close to the origin Subclavian Color Doppler

Subclavian Spectral Doppler

Subclavian Spectral Analysis High resistance Reversal late systole/early diastole

Repeat on left

Online form PSV EDV PSV

Tips/tricks

Long ECA/ICA Two for the price of one Satisfies the Long ICA & Long ECA B-mode requirements; do not have to do x2 separate images

Long ECA/ICA Two for the price of one Satisfies the Long ICA & Long ECA B-mode requirements; do not have to do x2 separate images

Branches = ECA

Tap on superficial temporal artery ant/sup to ear Indicates ECA Temporal Tap Tap on superficial temporal artery ant/sup to ear Indicates ECA Not reliable http://www.slideshare.net/shaffar75/doppler-ultrasound-of-carotid-arteries

Even w/ normal pts, you can get a + temp tap in the ICA In pt’s w/ a significant stenosis of the ECA, results of temp tap may be - in ECA & + in ICA http://www.slideshare.net/shaffar75/doppler-ultrasound-of-carotid-arteries

Bulb “ICA Prox” Widened portion of the proximal ICA Disturbed flow Unidirectional along the flow divider of the birfurcation Zero/reversed flow at outer wall

Vertebral Origin Most common location for stenoses

Not required unless pathology is suspected CCA Subclav Innominate Not required unless pathology is suspected

Innominate Not required unless pathology is suspected

Image quality Distal ICA can be difficult to demonstrate Prox/Mid ICA Doppler settings are not adequate to optimize the distal ICA adjustments must be made

Lowered Color Frequency

Increase Color Gain

Decreased Steer Box Angle

By making x3 adjustments After Before

The end