Neuroradiology 8, 149-- 155 (1974) © by Springer-Verlag 1974 Some Technique-Dependent Patterns of Collateral Flow during Cerebral Angiography* J.F. Seeger T.O. Gabrielsen, and R.E. Latehaw Department of Radiology, University of Michigan Medical Center, Ann Arbor, Mich. 48104, USA Received: January 14, 1974 Summary. During selective transfemoral catheter sage bidirectionnel de ces anastomoses, en rapport avec cerebral angiography, anastomoses between external le vaisseau injeet6. La visualisation de ces anastomoses se carotid branches and the vertebral artery, between the produit de facon variable d@end parrots enti6rement de vertebral and deep or ascending cervical arteries, and la technique, refldtant une augmentation transitoire de la between the middle meningeal and ophthalmic arteries pression dans l'art~re durant l'injeetion du produit de can be demonstrated fairly frequently in patients with no contraste. Par consgquent, l'observation d'une circulation known vascular abnormalities. One can occasionally artdrielle eollat6rale extraergnienne pendant une anglo- show bidirectional filling of these anastomoses depending graphic e6r6brale ne repr6sente pas n6cdssairement un on the vessel injected. Visualization of these anastomoses phdnomgne anormal tel qu'on le rencontre darts les occurs to a variable degree and is sometimes entirely troubles art6riels occlusifs, duns les malformations vas- technique-dependent, reflecting a ~ransient increase in the culaires et dans les tumeurs vascularis6es. intraluminal pressure during the injection of contrast medium. -- Thus, demonstration of extracranial collateral Einige technische Besonderheiten des kollateralen Blut- arterial flow during cerebral angiography should not durchflusses w#thrend der cerebralen Angiographie necessarily be interpreted as an abnormal phenomenon, Zusam~z~enfassung. W/~hrend der selektiven transfe- such as may be seen with arterial occlusive disease, vas- moralen Katheter-Angiographie k6nnen sich Anastomo- cular malformation, or a very vascular tumor. sen zwischen Externa-Gefggen und der A. vertebralis, zwischen der A. vertebralis und tiefen oder aufsteigenden eervicalen Arterien und zwischen der A. meningica media Quelques particularites techniques de la circulation col- und der A. ophthalmica darstellen. Diese Befunde finden latdrale au coats de l'angiographie cdr@brale sich auch bet Patienten, bet denen keine Geffil?anomalien Rdsumd. Au cours de l'angiographie c6rdbrale par vorliegen. Gelegentlich wird ein bidirektionaler Kontrast- eath6t6rismes s61ectifs par vote f6morale, peuvent ap- mitteldurchflul3 durch diese Anastomosen nachgewiesen, paraltre des anastomoses entre des branches carobidiennes dabei ist die Kontrastmittelffillung yon der Lokalisation externes et l'art6re vert6brale, entre l'art@re vert6brale et der Kontrastmittelinjektion abh/~ngig. Es zeigt sich also, les art6res c6r6brales profondes ou aseendantcs et entre dab diese unterschiedliehen DurchstrSmungen technisch l'art6re m6ning6e moyenne et l'art6re ophtalmique. Oc- bedingt werden k6nnen und nicht immer als abnormales easionnellement, on peut mettre en 6vidence un remplis- Ph~nomen gedeutet werden k6nnen. Introduction The presence of anastomoses between the external carotid and vertebral arteries, between the vertebral and ascending and deep cervical arteries, and between the middle meningeal and ophthalmic arteries is well known. Such communications are best demonstrated angiographieally when they serve as collateral chan- nels in patients with vascular occlusive disease or vas- cular malformations [4, 6, 19, 22, 28]. In our experience, by performing cerebral angio- graphy routinely by selective catheterization, we have shown these anastomoses fairly frequently in patients with no known vascular abnormalities. Visualization of these anastomoses is to a large degree a function of the technique of the examination. Occipital- Vertebral Anastomosis An anastomosis between the occipital branch of the external carotid artery and the vertebral artery was * Presented in part at Tenth Annual Meeting of The American Society of Neuroradiology, Mexico City, Mexico, Fig. 1. 6 year old girl with histiocytoma of right orbit. February 21--24, 1972. During part of this investigation, Lateral projection of right common carotid angiogram J.F. Seeger was a. NINDS Special Fellow No. 2 FII NS shows opaeifieation of vertebral and basilar arteries 2365-02 and R.E. Latehaw was a NINDS Special Fellow (solid arrows) via prominent anastomosis with occipital No. 1 Fll NS 02476-01. artery (open arrows) 150 J.F. Seeger et aL : Technique-Dependent Collateral Flow present in all of 53 cadavers studied by Schulze and the vertebral artery even during common carotid angio- Sauerbrey [23] and usually occurred at or near the graphy (Fig. 1). superior surface of the posterior arch of the atlas. Ac- Opacification of the occipital artery has also been cording to Gray [8], this communication is between the shown during vertebral angiography [20]. Richter [19] deep portion of the descending branch of the occipital mentioned that the occipital artery was opacified in artery and muscular branches of the vertebral artery. one of his 30 vertebral angiographies performed by Fig. 2. 6 year old boy with brain stem glioma, a) Lateral projection of right common carotid angiogram demons- trates occipital (open arrows) to vertebral (solid arrow) anastomosis, b) Lateral and e) frontal projections of right vertebral angiogram show reverse filling of this same anastomosis (open arrows), with subsequent opacifieation of external carotid artery branches Rare reports have appeared in the literature show- percutaneous puncture. With selective catheterization, ing opacification of this anastomosis in patients with- the vertebral to occipital anastomosis may be seen out known vascular disease, either due to inadvertent quite frequently during vertebral angiography even in introduction of contrast medium directly into the oc- patients who have no associated carotid occlusive dis- cipital artery [22] or deliberate or accidental external ease, vascular malformation or congenital anomaly. carotid angiography [2, 24]. If the anastomosis is Occasionally, bidirectional filling of this anastomosis large, in some cases perhaps representing a congenital can be demonstrated during selective carotid and anomaly, we occasionally have seen opacification of verteberal angiographies (Fig. 2). J.F. Seeger et al. : Technique-Dependent Collateral Flow 151 This normal anastomosis should not be confused rive external or common carotid angiographies but with various congenital anomalies such as a primitive have occasionally visualized the ascending pharyngeal hypoglossal artery or proatlantal intersegmental artery artery during selective vertebral angiographies (Figs. [26], nor should visualization of this anastomosis dur- 3, 4). Although we have not found it illustrated in text- ing common carotid angiography necessarily imply books of anatomy, the anastomosis between the as- hypoplasia or absence of the ipsilatcral vertebral artery cending pharyngeal artery and the vertebral artery in (Fig. 2). all our eases occurred anterior to the vertebral artery and inferior to the level of the vertebral-occipital anas- Ascending Pharyngeal- Vertebral Anastomosis tomosis, presumably between muscular branches of the Another anastomosis between the external carotid vertebral artery and prevertebral branches of the and vertebral arteries which rarely has been illustrated ascending pharyngeal artery [8, 18]. This localization Fig. 3. 30 year old woman with diplopia and left periorbital pain. Right vertebral angiogram, a) Lateral projection shows ascending pharyngeal artery (open arrows) opaeified by collaterals (small arrowheads) from vertebral artery. Collaterals (small arrows) to deep cervical artery (large solid arrows) are also demonstrated, b) Frontal projection shows ascending pharyngeal (open arrows) and deep cervical (solid arrows) arteries. Note congenital hypoplasia of right vertebral artery (large arrowheads) beyond origin of posterior inferior eerebellar artery in a) and b) angiographically involves the ascending pharyngeal is in agreement with the illustrations in the two pre- artery. Wiedenmann [29] reported a case of inadvert- vious ease reports [16, 29]. ent placement of a needle into the ascending pharyn- It is interesting to note that an occasional patient geal artery with opacification of a communication with will complain of a burning sensation in the back of the the vertebral artery during injection of 5 ml of con- throat during selective vertebral angiography. This is trast material. We have seen one such ease with presumably caused by contrast material entering the unintentional catheterization of the ascending pha- ascending pharyngeal artery through vertebral anas- ryngeal artery during attempted external carotid tomoses. angiography. Another example of this anastomosis was shown by Nierling et al., [16] during common carotid Vertebral-Ascending and/or -Deep Cervical Anastomoses angiography in a patient with occlusion of the internal The ascending and deep cervical arteries anasto- carotid artery. In patients without vascular abnormal- mose with each other, with the vertebral artery, and ities, we have not seen this anastomosis during selee- with the occipital artery [18]. The ascending cervical 152 J.F. Seeger et al. : Technique-Dependent Collateral Flow artery, lying somewhat more superficial and anterior internal or external carotid angiography may in