Phleboliths from venous malformations of the head and neck.

Objectives/hypothesis: Phleboliths in venous malformations (VM) of the head and neck are often observed and may cause significant symptoms. Only a few articles refer to the morphology and composition of the phleboliths in VM. The objective of this study was to analyse and to demonstrate their composition and morphology.

Methods: Patients with VM presenting to a vascular anomalies centre during a three-year period were identified. The incidence of phleboliths was analysed followed by morphological and structural analysis with cone beam tomography and X-ray diffraction.

Results: Phleboliths were identified in 28/98 patients with VM of the head and neck. Seven patients underwent conventional surgery to reduce the volume of the VM or to remove the phleboliths, which were localized in the cheek (3 cases), submandibular region (2 cases), infrahyoidal neck or upper eyelid (1 case each). The structural analysis showed that more advanced lamination and an increasing radiopacity of the cortex was observed in larger phleboliths. X-ray powder diffraction analysis revealed that the main constituent in the pulverized phleboliths was carbonate-fluorohydroxylapatite.

Conclusion: This study shows in a vivid way that phleboliths from VM of the head and neck area show a laminar structure and consist of apatite, without any indication of differences in their chemical composition. Treatment of localized intravascular coagulopathy in VM might be able to prevent the formation and the progression of phleboliths. Hypothetically, another option might be lithotripsy.