1 - Neuroradiology Department, Centro Hospitalar Universitário de Lisboa Central, Lisbon, Portugal
- 45th ESNR Annual Meeting, 14-18 Setembro, Lisboa
- Neuroradiology (2022) 64 (Suppl 1):S1-S165 https://doi.org/10.1007/s00234-022-03012-w
Introduction: The recognition of tortuous, dilated vessels on brain imaging is not always a manifestation of arteriovenous malformations or fistulas. Less common cerebrovascular disorders should also be considered, including pure arterial malformations (PAMs). Defined as dilated, overlapping, and tortuous arteries with a coil-like appearance and/or a mass of arterial loops in the absence of any venous components, most reported cases of PAMs were incidentally diagnosed. There is still debate on the optimal management, but conservative treatment has been proposed as these lesions are generally asymptomatic and stable. We report 8 cases of PAMs and discuss their distinguishing features.
Methods & Results: We retrospectively collected cases of patients with PAMs and reviewed the demographic and clinical characteristics, imaging findings, and follow-up data. Eight patients met the inclusion criteria. Six (75%) were female. The mean age at diagnosis was 5 years (patients aged between 2 months and 10 years). The symptoms and reason for imaging varied, with 6 patients (75%) presenting with segmental infantile hemangiomas and/or congenital anomalies, later confirmed PHACE syndrome; 1 with headache; and 1 with fine postural tremor and suspected developmental delay. Involvement of the posterior cerebral artery and posterior communicating artery was the most common (7 lesions affecting at least one of these arteries). The supraclinoid internal carotid artery was involved in 3 cases; in 2 cases each the anterior cerebral artery and the superior cerebellar artery; and the middle cerebral artery in 1 case. An associated aneurysm was present in two patients, both located in the posterior cerebral artery. None had intracranial hemorrhage or infarction attributed to the PAMs. Endovascular treatment was attempted in one patient with unsuccessful aneurysm embolization. Five patients had available followup MR imaging that showed no changes.
Discussion & Conclusion: PAMs are rare cerebrovascular disorders that can affect any intracranial artery and may be associated with aneurysms. Often incidental findings and mostly diagnosed in young women, its etiopathogenesis remains unclear. Distinction from other vascular abnormalities and accurate characterization of the PAMs’ architecture are mandatory, avoiding unnecessary invasive procedures. Given their benign natural history, it has been proposed that patients with PAMs should be managed conservatively with serial imaging. However, according to the literature, endovascular treatment could be considered when local aneurysms are present. Further investigation on this topic is needed to address and better elucidate the etiology, clinical course, and management of these probably underdiagnosed entities.
Keywords: pure arterial malformations (PAMs); PHACE; cerebral vascular malformations