Central nervous system vascular malformations: A clinical review

Abstract

CNS vascular malformation is an umbrella term that encompasses a wide variety of pathologies, with a wide range of therapeutic and diagnostic importance. This range spans lesions with a risk of devastating neurological compromise to lesions with a slow, static or benign course. Advances in neurovascular imaging along with increased utilization of these advances, have resulted in more frequent identification of these lesions. In this article, we provide an overview on definitions and classifications of CNS vascular malformations and outline the etiologic, diagnostic, prognostic, and therapeutic features for each entity. This review covers intracranial and spinal cord vascular malformations and discusses syndromes associated with CNS vascular malformations.

Keywords: central nervous system; intracranial; prognosis; spinal cord; vascular malformation.

Figure 1

Top Row: A 12‐year‐old boy presenting with acute onset loss of consciousness, left hemiparesis, and left hemibody sensory loss. Axial noncontrast CT (A) showed acute right parietal intracranial hemorrhage with midline shift. Axial MRI T2W images postemergent evacuation of the hematoma, with resolution of mass effect (B, C). Right internal carotid artery angiogram demonstrating a small right parietal arteriovenous malformation (AVM) (arrow), with an intra‐nidal aneurysm (arrowhead) compatible with the rupture site (D, F). Bottom Row: An 18‐year‐old man with headaches, difficulty walking, and hearing a whooshing sound after taking a flight for the first time. Noncontrast CT (G) and brain MRI (H, I) showed a large left thalamic mass causing moderate obstructive hydrocephalus. MRA (J) showed a large vascular lesion with numerous enhancing tortuous vessels (arrow) in the left thalamus extending inferiorly to midbrain. Vertebral angiography (K) confirmed AVM with the dominant supply from the left posterior cerebral artery and deep venous drainage.

Figure 2

A middle‐aged man with seizure, headache, and right visual field disturbance. Axial noncontrast head CT demonstrating calcification in the walls of the left occipital veins (arrow) indicating long‐standing venous hypertension (A). Axial images from noncontrast MRA head, demonstrating an asymmetrically enlarged left occipital artery (arrowhead). Arterialized veins (arrows) are seen in the left occipital and temporal lobes (B, C). Lateral views of left occipital artery angiogram demonstrating a venous recipient pouch in the left transverse sinus wall (arrowhead) with retrograde cortical venous drainage (arrows) (D, E). Imaging consistent with high‐grade dural arteriovenous shunt. A 77‐year‐old woman presenting with swollen preseptal soft tissues, proptosis, conjunctival injection, and eye pain. Axial reconstructions of a CTA Head demonstrating right eye proptosis (yellow arrow) and an asymmetrically enlarged and enhancing superior ophthalmic vein (arrowhead). Lateral views of the right internal carotid angiogram show an indirect CCF, with opacification of the superior ophthalmic vein (arrowhead) and right Cavernous sinus (arrow), with the absence of the ipsilateral inferior petrosal sinus (IPS), including on the normal venous phase of the brain (star denotes expected location).

Figure 3

A 6‐day‐old boy with high output heart failure, pulmonary hypertension, and reversed diastolic aortic flow. Axial & Sagittal T2W MRI brain showing dilated medial prosencephalic vein (arrow) and persistent falcine sinus (arrowhead) (A, B). The visualized brain parenchyma is normal for age. Sagittal 3D reconstruction of noncontrast MRA head demonstrating arterial pedicles from the limbic arcade (arrows) supplying the vein of Galen malformation (C). Patient with familial Cavernoma. Axial GRE (blood‐sensitive) images demonstrating the classical “popcorn” appearance of a large right frontal lobe CM (arrow) with classical imaging findings of blood in different stages of breakdown (both high & low T2 signal, high and low T1 signal), hypointense rim on T2W images and surrounding vasogenic edema (D, E). Multiple foci of susceptibility in the right and left hemispheres of the brain (arrowheads) compatible with multiple cavernous malformations (F).

Figure 4

Axial postcontrast T1W MRI demonstrating a typical dural venous anomaly (arrowheads) (A,B,C,D) with a “medusa’s head (arrow) (B). Coronal images from a CT with venous phase, demonstrating the dural venous anomaly (arrowheads) extending from the ependymal surface to the cortical surface (F,G,H,I).

Figure 5

A 60‐year‐old man presenting with a 1‐year history of increasing lower extremity weakness, and now with occasional bladder and bowel incontinence. Sagittal MRI T2W images of the left spine demonstrating abnormal increased T2 signal in the cord (arrowhead) and serpiginous vascular structure (arrow) interspersed among the normal nerve roots (A, B). Sagittal MRI STIR image of thoracic spine demonstrating the significant extent of the cord edema (arrowheads) (C). Axial MRI T2W image, demonstrating abnormal increased T2 signal, primarily affecting the central grey matter (arrow) (D). Sagittal postcontrast T1W image demonstrating patchy enhancement of the spinal cord (arrow) (E). AP un‐subtracted and subtracted angiography of the right L4 segmental artery demonstrating the point of AV shunting (arrowhead) in the neural foramen, and the retrograde venous drainage in the enlarged radiculomedullary vein extending cranially to the spinal cord (arrow) confirming the diagnosis of dural arteriovenous shunt (F, G). Subtracted image postembolization with NBCA (glue) demonstrating the glue cast filling the point of AV shunting (arrowhead) and the draining vein (arrow), necessary for achieving cure (H).

Figure 6

A 40‐year‐old man presenting with lower extremity radicular pain. Sagittal T2W MR left spine showing normal cord signal, but abnormal vascular flow voids along the dorsal surface of the lower spinal cord (arrowhead) (A). High‐resolution postcontrast T1W view of the left spine demonstrating abnormally enlarged and serpiginous enhancing vessels along the ventral and dorsal surfaces of the cord (arrowheads) (B). AP views subtracted from a DSA injection of the right T12 intercostal artery, demonstrating an enlarged radiculopial artery (arrow) extending to the anterior spinal artery (ASA) (arrowhead), with a classic hairpin turn (curved arrow). The ASA is slightly enlarged and extends to the point of AV shunting at the level of the conus medullaris (fat arrow). The abnormally dilated and enlarged draining vein is seen extending along the dorsal surface of the cord (star) (C, D). Image findings consistent with pial arteriovenous.

Figure 7

MRI axial and coronal postcontrast T1‐weighted images demonstrating multiple enhancing intra‐axial cerebellar nodules and nodules on the pial surface of the spinal cord (arrowheads) (A, B). MRI coronal postcontrast T1W image demonstrating classic “cyst & mural nodule appearance” of right cerebellar lesion (C). Vertebral artery DSA demonstrating multiple hypervascular nodules (arrows) along the cervical cord consistent with hemangioblastomas (D, E). Left vertebral artery injection with multiple hemangioblastomas, with ASA (arrowhead) supply (F, G). Figure H shows microcatheter injections of segmental artery supply to larger hemangioblastoma at the Craniocervical junction.

Figure 8

A: 14‐year‐old girl with evidence for arterial abnormalities on standard screening studies. 3D reconstruction of angiography from a right internal carotid artery injection demonstrating multiple small aneurysms (green arrows) arising from a dysplastic appearing supraclinoid region. In addition, focal dysplastic widening of the right posterior communicating artery (blue arrow), small right posterior cerebral artery aneurysm (green arrow), and dysplastic narrowing of the right posterior cerebral artery were observed. B: A 4‐year‐old patient with Sturge‐Weber syndrome. Brain MRI demonstrates asymmetric volume loss (T1), calcification (T2 signal), and abnormal enhancement (pial angiomatosis) in the sulci and surface of the right cerebral hemisphere (T1 postcontrast). C: A previously healthy toddler with acute onset apnea and choking. Noncontrast CT scan demonstrating subarachnoid hemorrhage and subdural hematoma. Axial T2W MRI brain, with abnormal vascular structure (recipient venous pouch) along medial margin of right parietal lobe (arrow). Aangiography demonstrating the enlarged right anterior cerebral artery supplying the right parietal arteriovenous shunt with dilated recipient venous pouch (arrows). AP left vertebral angiogram demonstrating a separate posterior fossa arteriovenous shunt (arrow).

Figure 9

A 4‐year‐old girl presenting with acute onset quadriparesis and sensory deficit. Found to have Type IV cervical pial AVF with CM‐AVM syndrome (RASA 1 mutation): acute onset quadriparesis and sensory deficit. Sagittal T2W, T1W, and GRE MRI images of the cervical cord demonstrating long segment edema (arrow heads) in the cord, as well as a hemorrhagic lesion (arrows) at the C7/T1 level (A, B, C). Subarachnoid hemorrhage is seen as well (curved arrow) (C). Axial T2W &T1W images at C7/T1 showing products of hemorrhage (low T2, high T1, arrows) (D,E). Left vertebral artery injection demonstrating a Type IV C pial AVF with a recipient intramedullary venous varix as the site of hemorrhage (arrow). Roadmap image demonstrating microcatheter placement for embolization of the AVF (F, G).