This is an MR Angiography sequence of a 46-year old male patient who was being investigated for TIA. The image sequence shows 3-D Time of Flight (TOF) Spoiled Gradient Recall (SPGR) Echo Acquisition images. It shows the Vertebrobasilar and Carotid systems of Cerebral circulation. An incidental finding was abnormal Right Vertebral artery - Narrow, Double, Accessory, Communication with Right Internal Carotid. The best way to visualize the image is by slideshow - imagine the head is rotating clockwise. There are plenty of labels in the images to guide the viewer.

1. Abnormal Right
Vertebral Artery
Dr. Sanjoy Sanyal
Associate Dean and Clinical Neuroscience Professor

2. Abnormal Right Vertebral Artery
• This is a composite
MRA image of the
Cerebral Circulation
• Next slide contains an
embedded video of 3-
D Time of Flight (TOF)
Spoiled Gradient
Recall (SPGR) Echo
MRA images
• The slides thereafter
are enlarged screen
shots from the MRA
series

3. Abnormal Right Vertebral Artery
• All are enlarged
screen shots of
3-D Time of
Flight (TOF)
Spoiled Gradient
Recall (SPGR)
Echo Acquisition
MRA series
• Narrow Right
Vertebral Artery
is clearly visible
in this image

4. Abnormal Right Vertebral Artery
• The successive
MRA images
are TOF
sequence, as if
the Head is
rotating
clockwise
• An ‘Accessory’
Right Vertebral
Artery becomes
visible in this
image

5. Abnormal Right Vertebral Artery
• Narrow Right
Vertebral Artery
is clearly visible
• The ‘Accessory’
Vertebral Artery
is clearly
separate from
the narrow one
on the right side

6. Abnormal Right Vertebral Artery
• Continuing with
Time of Flight
(TOF) Spoiled
Gradient Recall
(SPGR) Echo
Acquisition series
of MRA Images
• Same findings as
previous slide
• Imagine the head
is rotating
clockwise

7. Abnormal Right Vertebral Artery
• The ‘Accessory’ Right
Vertebral Artery gives
a communication to
Right Internal Carotid
and to the Right
Vertebral Artery
• This can be seen in
the embedded video
in the last slide
• The Accessory Artery
is intermediate in size
between normal Left
Vertebral Artery and
narrow Right
Vertebral Artery

8. Abnormal Right Vertebral Artery
• The ‘Accessory’
Artery itself is
moving further
postero-laterally
with the clockwise
rotation of head
• Narrow Right
Vertebral Artery is
clearly visible as
a bifid artery

9. Abnormal Right Vertebral Artery
• ‘Accessory’ Right
Vertebral Artery has a
separate distribution
on the Right side
which does not have
a counterpart on the
Left side
• Narrow Right
Vertebral Artery and
communication with
Right Internal Carotid
are clearly visible

10. Abnormal Right Vertebral Artery
• These images are
screen grab views
of a 3-D Time of
Flight (TOF)
Spoiled Gradient
Recall (SPGR)
Echo Acquisition
MRA Images
• Same findings as
previous slide

11. Abnormal Right Vertebral Artery
• These images are
screen grab views of
a 3-D Time of Flight
(TOF) Spoiled
Gradient Recall
(SPGR) Echo
Acquisition MRA
Images
• The next slide gives
the embedded video
of the 2-D TOF axial
slice sequence of
MRA images

12. Thank you for watching