Relevant Cerebro-Vascular Relevant Cerebro-Vascular Anatomy for Carotid Anatomy for Carotid

Intervention Intervention

Ricardo A Hanel, MDRicardo A Hanel, MDElad Levy, MDElad Levy, MD

L N Hopkins, MDL N Hopkins, MD

Cerebrovascular Cerebrovascular AnatomyAnatomy

Why should I learn it For CAS ?Why should I learn it For CAS ?

Basic anatomy and Basic anatomy and collateral circulation is collateral circulation is enoughenough

Always obtain baseline Always obtain baseline films for comparisonfilms for comparison

Knowing the anatomy Knowing the anatomy helps avoid complicationshelps avoid complications

2 ICA’s &VA’s carry 2 ICA’s &VA’s carry 20% of Cardiac OP20% of Cardiac OP

ICA’s ICA’s fixed fixed from from skull base to skull base to supraclin ICAsupraclin ICA

VA’s fixed in VA’s fixed in vertebral foramen vertebral foramen

Carotid artery Carotid artery interventionsinterventions

Clinical applied Anatomy will Clinical applied Anatomy will influence:influence:– The best therapeutic option (CEA x CAS)The best therapeutic option (CEA x CAS)– The best Access (femoral, brachial, The best Access (femoral, brachial,

direct)direct)– Device selectionDevice selection– Complication avoidanceComplication avoidance– Complication managementComplication management

Aortic Arch ViewsAortic Arch Views

Arch angio to assess Arch angio to assess accessaccess

LAO 30-45 degrees LAO 30-45 degrees bestbest

Multiple views…origin Multiple views…origin dsds

RAO 20.. R subclavian RAO 20.. R subclavian from RCCAfrom RCCA

Carotid ArteryCarotid Artery

Variability enormousVariability enormous Bifurcation C1 – T2Bifurcation C1 – T2 Best working view… Best working view…

lat/obl lat/obl Bony landmarksBony landmarks … …

-Unsubtract-Unsubtract

Skull Base

Petrous Carotid

ECA

ICA

Cervical Carotid ViewsCervical Carotid Views

Obtain AP, Lateral and Obtain AP, Lateral and Oblique projectionsOblique projections

Clear ICA origin from Clear ICA origin from ECAECA

Evaluate for dissection, Evaluate for dissection, thrombus, calcium, thrombus, calcium, kinkskinks

Measurements using Measurements using NASCET criteriaNASCET criteria– 1 - (Stenosis 1 - (Stenosis

diameter/Non-tapered diameter/Non-tapered segment diameter)segment diameter)

Cervical ICA

“No Branches”Hi flow…Don’t overdilate!

Fixed near skull baseCarotid Sinus

What is this??

Where to put the filter?

PcommOtic

Primitive trigeminalHypoglossalPro atlantal

ConnectionsICA to VA

ECA anatomyECA anatomy

ECA Branches

1. Key source of collateral2. Anastomoses to ICA or VA3. Stent will not occlude ECA

When handling the ECA When handling the ECA remember…remember…

EC-IC anastomosis commonEC-IC anastomosis common May not be seen on angiogramMay not be seen on angiogram With major With major vessel occlusonvessel occluson these these

anastomosis may anastomosis may hypertrophyhypertrophy ECA embolus may cause strokeECA embolus may cause stroke BE AWARE!BE AWARE!

Post-intervention CineE. Deflate the GuardWire® protection balloon and evaluate final result

The GuardWire® Balloon Protected Procedure

Pre-intervention Cine

The GuardWire® Balloon Protected Procedure

Carotid stenting sampleSVG with covered stent sample

Complication: Visual Loss due to retrograde embolization of retinal arteries via ECA branches

ICA AnatomyICA Anatomy

Base of Skull

Petrous ICA

Cavernous ICA

Ophthalmic a

Supraclinoid ICA

ICA becomes fixed 2-3mm ICA becomes fixed 2-3mm proximal to skull base proximal to skull base

Petrous ICA up to supraclinoid ICA Petrous ICA up to supraclinoid ICA fixed in bone/ligamentous/dural fixed in bone/ligamentous/dural encasementencasement

Intracranial vessels more mobile Intracranial vessels more mobile but fragile and easily but fragile and easily damaged/ruptureddamaged/ruptured

Onward and Upward…Onward and Upward…

Skull Base From Below

ICA Entrance

•Horizontal Petrous ICA

ANT

Post

Skull Base From Above

Ant

PostHoriz Petrous ICA

Petrocavernous ICASide View - Right

Ascending Petrous

Cavernous

Cavernous – Supraclinoid ICA

Anterior Medial Loop

HorizontalCavernous ICA

Supraclinoid ICA

Perforators

Post Communicating

Quiz … What is Quiz … What is this??this??

Although Although uncommon, carotid-uncommon, carotid-basilar basilar anastomoses, other anastomoses, other then PComm, may then PComm, may occur: occur: – Persistent trigeminal Persistent trigeminal

artery (0.25%)artery (0.25%) From Cavernous ICA From Cavernous ICA

to basilarto basilar

PrimitiveTrigeminal

Ascending Petrous ICA

Intracranial Vascular Intracranial Vascular AnatomyAnatomy

After giving origin to the After giving origin to the Ophthalmic A, PComm and Ant Ophthalmic A, PComm and Ant Choroidal artery the ICA finally Choroidal artery the ICA finally bifurcates into the Anterior bifurcates into the Anterior Cerebral Artery - ACA and Middle Cerebral Artery - ACA and Middle Cerebral Artery – MCACerebral Artery – MCA

Intracranial Vascular Intracranial Vascular AnatomyAnatomy

A Must….pre op AP and Lateral AngioHave them handy!!!!

Variations are the RuleVariations are the Rule

Many variations Many variations of these vessels of these vessels

Always have pre Always have pre op films to op films to compare in case compare in case of troubleof trouble

And always do a And always do a baseline Neuro baseline Neuro exam pre opexam pre op

3 M-2 branches

MCA embolus ?????

The Circle of WillisThe Circle of Willis

Connection between:Connection between:– Carotid-basilar systemCarotid-basilar system– Rt/Lt sideRt/Lt side– Vessels involved:Vessels involved:

ACAs & ACommACAs & AComm ICAs & PCommsICAs & PComms PCAsPCAs Basilar Basilar

T/F : The Circle is Always Intact ??

Acomm

Pcomm

Pcomm

Pcomm

The Circle of WillisThe Circle of Willis

The Circle of Willis is The Circle of Willis is complete in only 30-complete in only 30-40% of the cases40% of the cases

Many variationsMany variations Hypoplasia of one of Hypoplasia of one of

the A-1 segments of the A-1 segments of the ACAs…the ACAs…

Or ICA stenosis???Or ICA stenosis???

A-1

What is this?

MCA & ACA AnatomyMCA & ACA Anatomy

ACA

MCA

M-1M-2

ACAA-2

AcommA-1

MCA

Where is the ACA ?

MCA …MCA …Many VariationsMany Variations

ACA AnatomyACA Anatomy

A-1

A-2

A-2

PComm

Variations, variations, Variations, variations, variations …variations … Message ???

Vertebral Artery Vertebral Artery AnatomyAnatomy

Rich Muscular Collateral

Variations, variations, Variations, variations, variations …variations …

A complete diagnostic angiogram A complete diagnostic angiogram with clinical/anatomical with clinical/anatomical correlation should be performed correlation should be performed and available before any major and available before any major interventionintervention

ICA OcclsionICA Occlsion

R ICA Occl with R ICA Occl with CollateralCollateral

……Circle of WillisCircle of Willis

L Carotid R Vertebral

R ICA Occl with Pial R ICA Occl with Pial CollateralCollateral

R ICA Occl with R ICA Occl with Vertebral Collateral to Vertebral Collateral to MCAMCA

PComm

ICA Occlusion with ICA Occlusion with Ophthalmic CollateralOphthalmic Collateral

L CCA

OphthalmicTo ICA

R ICA Occl with Ophthalmic R ICA Occl with Ophthalmic

and Pial Collateraland Pial Collateral

Vascular TerritoriesVascular Territories

Normal AngiogramNormal AngiogramCapillary PhaseCapillary Phase

Pre EmbolusPre Embolus

Capillary PhaseCapillary Phase

Post Embolus

ComplicationsComplications

Interventional Interventional procedure going procedure going uneventfully until…..uneventfully until…..

Pt agitated & Pt agitated & hemiparetichemiparetic

What is this?What is this? What should you do?What should you do?

ComplicationsComplicationsIntracerebral HemorrhageIntracerebral Hemorrhage

ACA and MCA spread…Barrel Shift

HemorrhageHemorrhage

CT ScanCT Scan You DO NOT need to You DO NOT need to

angiographically visualize angiographically visualize extravasation to have extravasation to have bleeding.bleeding.

What is This ?

Proceed with CAS ??

And this ?

…And This ??

Dangerous AnatomyDangerous Anatomy

Elderly PatientElderly Patient

““Corkscrew” CarotidCorkscrew” Carotid

Stay Away!!Stay Away!!

Trouble …for sure!Trouble …for sure!

Judgement!Judgement!!!

Backing out is OKBacking out is OK

Causing a Stroke is Causing a Stroke is NotNot Roubin

Catheter skills Catheter skills ++

Anatomic Knowledge Anatomic Knowledge = =

Better resultsBetter results

Conclusion…Conclusion…