Cervical and intracranial arterial anomalies in 70 patients with PHACE syndrome

Abstract

Background and purpose: Cerebral and cervical arterial abnormalities are the most common non-cutaneous anomaly in PHACE syndrome, but the location and type of arterial lesions that occur have not been systematically assessed in a large cohort. Our aim was to characterize the phenotypic spectrum of arteriopathy, assess the frequency with which different arteries are involved, and evaluate spatial relationships between arteriopathy, brain structural lesions, and hemangiomas in PHACE syndrome.

Materials and methods: Intracranial MRA and/or CTA images from 70 children and accompanying brain MR images in 59 patients with arteriopathy and PHACE syndrome were reviewed to identify the type and location of arterial lesions and brain abnormalities. Five categories of arteriopathy were identified and used for classification: dysgenesis, narrowing, nonvisualization, primitive embryonic carotid-vertebrobasilar connections, and anomalous arterial course or origin. Univariate logistic regression analyses were performed to test for associations between arteriopathy location, hemangiomas, and brain abnormalities.

Results: By study design, all patients had arterial abnormalities, and 57% had >1 form of arteriopathy. Dysgenesis was the most common abnormality (56%), followed by anomalous course and/or origin (47%), narrowing (39%), and nonvisualization (20%). Primitive embryonic carotid-vertebrobasilar connections were present in 20% of children. Hemangiomas were ipsilateral to arteriopathy in all but 1 case. The frontotemporal and/or mandibular facial segments were involved in 97% of cases, but no other specific associations between arteriopathy location and hemangioma sites were detected. All cases with posterior fossa anomalies had either ICA anomalies or persistent embryonic carotid-basilar connections.

Conclusions: The arteriopathy of PHACE syndrome commonly involves the ICA and its embryonic branches, ipsilateral to the cutaneous hemangioma, with dysgenesis and abnormal arterial course the most commonly noted abnormalities. Brain abnormalities are also typically ipsilateral.

Fig 1.

Representative arterial dysgenesis images are shown as 3D volume renderings from MRA source data, generated by using OsiriX (http://www.osirix-viewer.com/Downloads.html). A, Enlargement of the right ICA, MCA, and ACA (white asterisks). There is also an accessory left MCA (red arrow), and the left PCA is duplicated with an anomalous branching pattern (red asterisk). B, Proximal irregularity of a markedly enlarged left ICA (red arrows) and tortuosity of the right PCA (white asterisk). The origin of the right MCA (white arrow) is also anomalous, arising from the cavernous ICA. C, Looping course of the left M1 segment (white arrow) and enlarged left A1/A2 junction (red arrow). D, Marked dysgenesis of the cavernous and supraclinoid right ICA (red arrow) and contralateral dysgenesis of the cavernous and supraclinoid left ICA (white arrows). Note also that the right ICA is not visualized proximal to the cavernous sinus, the right PcomA supplies the right MCA, and the right MCA is markedly narrowed (white asterisks).

Fig 2.

Anomalous course and/or origin. A, 3D rendering from MRA shows elongation of the right PcomA, an anomalous connection between the right P1 segment and the right MCA (red arrow). The right ICA and left PCA are also diffusely narrow (white arrow), and the right A1 segment is hypoplastic (white asterisk). B, 3D rendering from CTA shows the tortuous looped course of the supraclinoid right ICA (white arrow). Note also the presence of 2 ACAs, a separate artery of the corpus callosum, and aneurysms at the right carotid terminus and distal right A1 segment (white asterisks). Volume renderings were generated by using OsiriX.

Fig 3.

Arterial narrowing and nonvisualization. All images are shown as maximum-intensity-projection reconstructions from MRA source data. A, Submentovertex projection showing nonvisualization of the left ICA. B, AP projection shows long-segment narrowing of the entire visualized course of the right ICA (red arrow). C, AP projection shows nonvisualization of the left ICA from the distal cervical to the cavernous segments. The intradural left VA is also absent. D, AP projection shows absence of the entire left ICA and long-segment tapered narrowing and luminal irregularity of the distal cervical right ICA (red arrow).

Fig 4.

Examples of segmental and pleurisegmental ICA dysgenesis. Lesions of the ICA, especially dysgenesis, narrowing, and nonvisualization, often involve the entire length of the artery (red arrows, A) or relatively long portions of the artery corresponding to developmental segments (red arrow, B). The right proximal MCA shows diminished flow-related enhancement as well (red asterisk, A). There is segmental dysgenesis of the petrous left ICA with irregular enlargement of the artery (B). Note also a markedly enlarged left ECA, which supplies a large hemangioma, and an absent right A1 segment.