SULCOCOMMISURAL A. Anatomy of the Spinal Vessels
POSTERIOR RADICULAR / Mario Muto,, M.D. RADICULOPIAL A. Diagnostic and Interventional Neuroradiology Cardarelli Hosp., Naples, Italy DORSOSPINAL A.
ANTERIOR RADICULAR / RADICULOMEDULLARY A.
PROPER RADICULAR BRANCHES to DURA AND NERVE ROOTS
Challenges of Spinal Vascular Anatomy Dorsospinal Arteries Comprehensionp 31 pairs,p , arisingg from each segmentalg level,, to supplypp y Complexpy anatomy the nerve roots, localall duralall structures, and the spinal Complexp nomenclature cord Evolution of spinalp CTA and MRA ((pitfalls)p ProperP radicular branchess ending in nerve roots or dura Performance of Spinalp Angiography AnteriorA radicular / radiculomedullaryraadiculomedulla y arteries Longgp procedure supplingpp g the anterior spinalppy arteryy Techniqueq for selective catheterization Posterior radicular / radiculopialp all arteriess supplingpp g Occult,,p duplicated or common vessel origins the posterior spinal arteries and surfacee vasocoronana Anterior/posterior confusion
Radiculomedullaryy Arteries (6-8) Vascular Anatomy of the Spine LargeLargL e hairpinhahairpin arteriearterieses arteryartery which arise from the vertebral, ascending cervical, deep cervical, oor Selective microangiographyg thoracolumbar intercostal or lumbar segmensegmental Adamkieviczz 1881 arteries to supplypp y the anterior spinalp arteryy Kadyiyyii 1889 SuppliesSuS pplies anterior 2/3 of the crocrossssss-sectionalsectione spinal Gillilann 1958 cord area via the anterior spinal artery Lazorthess 1958 Corbin 1961 Houdartrt 1965 Di Chiro andd Doppmanpp n 1975 Thronn 1988,8,8 Lasjauniasasas-Berensteinn 2004 Anterior Spinal Artery (ASA) Radiculopial Arteries (10-20)
SingleS longitudinal artery located in the anterior median sulcus SmallerSmalS leer hairpinhahairpin arteriarteriesese whichw also arise fromfrom the vertebral,vertebertebrtebbrral, ascendiascendingng cervicacervical,l, deedeepp cervicalcervical,, or 50000-1000 micron in size thoracothoracco-lumbarluumbaru intercostal or lumbar segmentsegmental Mayyy or may not be continuous arteries to supply the posterior spinal artery Radiculomedullaryy arterial supply (66-8): network Generally evenly distributed throughout the spine Cervical (3(3-4)) Thoracic ()(1) Lumbar (11-2)
Majorj Contributors ArteryArteA ery of the CCervical Posterior Spinal Artery (PSA) Enlargementg arisesararises from vertebral or Continuous longitudinalg / vertical arterial system ascendingasscending cervicalal ararteries,rtteries, Actuallyy 4 vessels typically at the C55 - C6 levels Paired posteriorpppp and paired posterolateral spinal arteries Good collateral communication (vasocorona) 250500-500 micron size Arterial supplypp y from radiculopialp arteries SuppliesS poposterior 1/3 of the crossss-sectional spinal cord area
Major Contributors Vascular Supply of the Spinal Cord
The Arteryy of Adamkiewicz AnteriorA spinal artery arterya ofo lumbarlluumbum suppliessupplieplieess anterior 2/3 of enlargementg ntn crosscrosssss-sectionalsectioe spinal commonlyc y onn the left cord area. between T99-12 PosteriorP spinal arteries supply posterposterior 1/3 of spinal cord. Intrinsic Anastamoses What you cant see on angiography…
Intrinsic Blood Supply
Intrinsic Anastamoses Central Cord Supply
Sulcocommisuralal Arteries Arise from the ASA MoreMoM re numerousnumerous in cervical and lumbar areas Rami Perforantes Sulcocommisurals End arteries 500-75 micron SupplyS deepd white and gray matter
Cone bean DSA
Peripheral Cord Supply
Rami Perforantes What you can see… 255-50 microns More evenly distributed along cord than sulcocommisurals Extrinsic Blood Supply
Spinalp Vascular Segments Cervicoco-thoracic Thoracic Thoracococo-lumbar Sacral Cervical Vascular Supply Thoracic & Lumbar Segmental Supply
Segmentalg Radicular Arteries Intercostal Segmental Vertebral arteries Aorta PICA Ascendingg cervical artery Lumbar Segmental Thyroyrroo-cervical trunk Aorta Deepp cervical arteryy Lateral Sacral Arteries Costotoo-cervical trunk Hypogastricyp g Arteries Occipitalp arteries Median Sacral Artery External carotid arteryy Aortic Bifurcation Supremep Intercostal T1 or T2 level
Bronchial v. Intercostal Thoracolumbar Blood Supply
SegmentalSegmentS a intercostal and lumbar arteries AriseA from the righright posterolateral descendingg aorta Occasionally from bronchial arteries Lumbar Segmental Arteries Upper Thoracic Regional Supply
MostM poorlyp collateralized region of the cord Segmentalg Intercostal Arteries T2 throughg T7
Averageg Diameter 2.7mm (range 2.3.33-3.0mm) Bronchial Arteries
Typical Radiculomedullary Artery to ASA
Thoracolumbar Regional Supply Artery of Adamkievicz (1882)
Arteryyg of the Lumbar Enlargementnt Segmentalg Intercostal Arteries Dominant thoracolumbar artery (85% of T8 throughg T12 individuals)) >75 % arise from the left T99-12 segmental Lumbar Segmentalg Arteries arteryy Hypogastricsyp g Diameter of the origingy of the artery ranges from Sacrals 1.2 to 2.5 mm (g(average 1.89 mm) ) Initiallyy called "magnus ramuss radicularis anterior" Vascular Supply of the Conus Venous Drainage of the Cord
TheT termintterminalala arterialararterialr basbasketskeett representsrepresentse tthehee anastamosisannastamosis ofo the anteriorannterior spinal artery with the popposteriorsterio spinal arteries at the conus
Vascular Supply at the Sacral Level Noninvasive Spinal Vascular Imaging
Is it really there yet at most institutions?
MDCT
1.51 T – 3 T dynamic MRA with Dynamic sequence
Venous Drainage DAVFs Adamkiewicz artery
Intrinsic superficialp venous pplexus two longitudinalg veins anterior median spinalp vein posteriorposp terio median spinal vein Extrinsic posteriorp radicular vein anteriora radicular vein ExtraduralE / eepiduralpid venous plexus DCE-MRA-C.E. Neurinoma 0.3mmol/kg/45ml + 25ml saline flush FR-FSE T2 Inj. rate 3ml/sec FOV 500mm FSE Matrix 464x512 1.2 mm thick (range 75-85mm) T1+C TR 5.9ms,TE 1.9ms, FA 30
Adamkiewicz Art. Anterior spinal axis Neurinoma e-TRICKS: MIP
MRI pprotocol " '$ , !%&"$! % Sagg T1W Sagg T2W No S.C. swelling Ax T2W No S.C. compression +/- T1W+Gd ……….
absent (-), subtle (+), focal (++), or diffuse (+++)
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# $ ! ! ! # ! ! # MDCTMDCCT angiographyangiography detected engorgedengorged perimedullaryperimedullary " # " ! # $ ! ! $ # ! "$ drainingdrainiing veins and correctly localized the fistula of the SDAVFs, and correlated well with catheter angiography More common with low-flow arteriovenous fistulas Stroke. 2005;36:1562-1564 $$$% * * $ $ * ! % ) * $! * !' - )%% ! 74 " !$ % % ) "!$& % !$ 5< & &% (& '%#' & ) !' & " %' $ !$ &! %- '$!$! - 645; "+7<0=1,5<58/5<5=- !, 54-75;8. $-96;9- "' 645; ' 64- , 6<;6=6=:-
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-the fistula Not selective Selective and magnified Not selective Small FOV Large FOV -mildly enlarged anterior spinal artery -Multiple engorged outflow veins -anterior spinal artery feeder $$$% * * $ $ * ! % ) * $! * !' - )%% ! 74 " !$ % % ) "!$& % !$ 5< & &% (& '%#' & ) !' & " %' $ !$ &! %- '$!$! - 645; "+7<0=1,5<58/5<5=- !, 54-75;8. $-96;9- "' 645; ' 64- , 6<;6=6=:- from the left T8 intercostal artery AJNR Am J Neuroradiol 27:813–17 Apr 2006
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Performance of Spinal Angiography
1. Carefully identify the vertebral levels investigated at the beginning of the procedure 2. Avoid, as much as possible, poor angiographic visualization related to nonselective injections Rationale and Utility 3. Perform a complete spinal angiogram— even if a lesion has already been documented—including the pelvis and the cervical region and, in selected Technique cases, the carotid arteries as well. 4. Meticulous analysis of angiographic images, optimized by electronic means such as best mask selection and pixel shifting. 5. Value of second readings and second opinions
$$$% * * $ $ * ! % ) * $! * !' - )%% ! 74 " !$ % % ) "!$& % !$ 5< & &% (& '%#' & ) !' & " %' $ !$ &! %- '$!$! - 645; "+7<0=1,5<58/5<5=- !, 54-75;8. $-96;9- "' 645; ' 64- , 6<;6=6=:- Performance of Spinal Angiography Technique
DiagnosisD of spinal vascuvascularl malformations General anesthesia is mandatoryy and occasionallyy tumors Glucagong (decrease( bowel gas and motility) PreoperativePreoperaP or palliative embolization of Foley Catheter tumors Embolization of vascular malformations NOT routinely for spinal cord ischemia
Technique Performance of Spinal Angiography Highgq quality y DSA Frontal planep C Islakk and N Kocer Lateral views at level of pathology if feasible ImagingI of ththe vascular disorders of the spine and Hand injectionsj spinalp cord 2-4 cc oof nononn-ionic contrast with breath holding or apneap ClinicalClinC ical NeuroradiologyNeuuroradiologyy - A.A RoviraRovirra, MM.. ThurnerThThurneer, F.F Barkhoff , R. Jaegerg Chap 71 pp 206767-2104 Radioioio-opaquepqp marker Springer Ed. 2019 Worksheet to track vessels studied
Which vessels to catheterize? Complete Selective Spinal Angiogram Cervical Vessels QuiteQ a longg examination for most ppatients Vertebral arteries Abilityyp to perform a complete selective study limited by Ascendingg Cervical Patient tolerance Deepp Cervical Physiciany endurance ExternalE Carotids Heat units Thoracolumbar Intercostals Contrast loadd (5(5-7 mg/kg) Middle Sacral Atherosclerosis Terminal Aorta Some patientspq require 2 sessions Lateral Sacral Arteries Renal compromisep or severe atherosclerosis Internal Iliac (Hypogastric) Arteries BiBi-femoral aortic flush with femoral compression Pigtail Flush in Proximal Descending Thanks for your attention
Complications
Approx.pp 1% with modern techniquesq SpasmSpSpasmm: SelectiveSeSelectivctivvee catheterizationcathheterizerizzatioonn ofo tthehee originorriginn of thee segmentalseegmentaentaala arteryarteryy maymam y bebe responsiblereresponsiblee e forfoor vasospasmvasospaspasmm. IInn case of a lowlooww-flowfloflf ow fistfistula,tulaa, thisthhis spasmspasmm maymam y reducereedducee the floww towardtoowardo d thethhe fisfistula, whichh couldcouldd bebe responsiblereesponsible forfoor the non visualizationn of the SDAVF.
Spinal Embolization
Variabilityy is the Rule! RadiculomedullaryR branches are generally considereconsideredd more dangerousg to embolize than radiculopialp branches Identifyyy levels of radiculomedullary arteries AssureAsA sure thatthat therethere is nono collateralcollateral communication across at least 3 adjacentj levels If unsure,, dononnt do it! EmbolizationE is more effective for controlling blood loss (tumors(tumors), BUT more dangerous than surgical clipping