Symptomatic arteriovenous malformation of the thyroid/parathyroid gland: A case report

Abstract

Arteriovenous malformations (AVMs) are complex vascular lesions most commonly found in the brain and infrequently found in the head and neck. AVMs are characterized by a tangle of blood vessels called a nidus, which shunts blood from an artery directly to a draining vein. Various treatments are available, including surgical resection and endovascular embolization. Here, we report the case of a 32-year-old male patient who complained of painful pulsating left neck swelling with dysphagia for 1 year, which turned out to be an AVM alongside the left thyroid gland. The AVM was treated by embolization using Onyx in 2 sessions. The patient has been free of symptoms since the treatment.

Keywords: Arteriovenous malformations; Head and neck; Para-thyroid; Thyroid; Vascular.

Fig. 1

(A) Axial and (B) Coronal enhanced CT show multiple engorged arteries at the left lower neck (arrows) involving the thyroid/parathyroid region giving appearance of (bag of worms).

Fig. 2

Diagnostic angiogram reveals a large high-flow arteriovenous malformation along the left lower neck adjacent to the left thyroid lobe with arterial feeders primarily through the left superior (A) and inferior (B) thyroidal arteries. (C) There is a small feeder artery that arises from on the right inferior thyroid artery. Significant shunting is noted (D) filling of the at least two large draining veins into the left internal jugular vein. No intranidal aneurysm is seen.

Fig. 3

(A) Digital subtracted image and (B) X-ray image post embolization by Onyx 18, demonstrating complete obliteration of the AVM.

Fig. 4

Two years follow-up angiogram (A) reveals recurrence of a small arteriovenous malformation feeding from the superior thyroid artery (arrow). (B) and (C) During and post injection of embolizing agent – Onyx 18 - illustrating complete obliteration of the residual AVM.

Fig. 5

A 2-years follow up MRA post contrast and post processing 3D reveals no evidence of recanalization.

Fig. 6

A time-line of the patient presentation illustrating the time period between the initial presentation, recurrence and resolution of symptoms.