1. 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!

2. Carotid duplex ultrasound
Jenelle Beadle
March, 2015

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

4. Anatomy

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

6. Extracranial Cerebrovascular System Innominate/brachiocephalic
Subclavian
Vertebral
Common Carotid (CCA)
Internal Carotid (ICA)
External Carotid (ECA)

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

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

9. Vertebral Arteries
Originate: Subclavian

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

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

12. External Carotid Arteries (ECA)
Originate: CCA

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

14. Internal Carotid Arteries (ICA)
Originate: CCA

15. NO extracranial branches

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

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

21. Innominate/Brachiocephalic

22. Rt Subclavian
Innominate/Brachiocephalic

23. Rt Vertebral
Rt Subclavian
Innominate/Brachiocephalic

24. Rt CCA
Rt Vertebral
Rt Subclavian
Innominate/Brachiocephalic

25. Rt ICA
Rt CCA
Rt Vertebral
Rt Subclavian
Innominate/Brachiocephalic

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

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

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

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

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

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

32. Anatomical variants

33. Numerous anatomical variants involving the aortic arch branches

34. 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%)

35. 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

36. 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

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

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

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

40. 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

41. ICA tortuosity variants
Course variations are common

42. ICA tortuosity variants
Course variations are common

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

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

45. Carotid duplex ultrasound

46. 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

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

48. 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

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

50. 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

51. 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

52. 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

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

54. CCA Proximal
Long

55. CCA Proximal
Color Doppler

56. CCA Proximal
Spectral Doppler

57. *2-3cm below the bifurcation
CCA Distal
Trans
Transducer: 6-15MHz

58. CCA Distal
Long

59. CCA Distal
Color Doppler

60. CCA Distal
Spectral Doppler

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

62. Bifurcation
Trans (bulb)

63. Bifurcation
Trans (just above bulb)

64. *Look for branches
ECA Prox
Long

65. ECA Prox
Color Doppler

66. ECA Prox
Spectral Doppler

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

68. *Include bulb
ICA Prox
Long

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

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

71. ICA Mid
Color Doppler

72. ICA Mid
Spectral Doppler

73. ICA Dist
Color Doppler

74. ICA Dist
Spectral Doppler

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

76. Vertebral
Color Doppler

77. Vertebral
Spectral Doppler

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

79. *Sampled close to the origin
Subclavian
Color Doppler

80. Subclavian
Spectral Doppler

81. Subclavian Spectral Analysis
High resistance
Reversal late systole/early diastole

82. Repeat on left

83. Online form
PSV
EDV
PSV

84. Tips/tricks

85. 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

86. 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

87. Branches = ECA

88. 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

89. 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

90. 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

91. Vertebral Origin
Most common location for stenoses

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

93. Innominate
Not required unless pathology is suspected

94. 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

95. Lowered Color Frequency

96. Increase Color Gain

97. Decreased Steer Box Angle

98. By making x3 adjustments
After
Before

99. The end