Arteriovenous malformation of the thyroid gland as a very rare cause of mechanical neck syndrome: a case report

INTRODUCTION: Vascular malformations of the thyroid gland represent a very rare, often accidentally diagnosed, disease that in the case of eufunctional goitre may be the cause of mechanical neck syndrome. The authors present here the complex differential-diagnosis and treatment approach and stress the importance of histopathology for determining the final diagnosis. CASE PRESENTATION: Using various imaging methods (ultrasound, multidetector computed tomography of the neck), the cause of breathing difficulties in a 64-year-old old man from the Czech Republic with normal thyroid gland function was found to be an arteriovenous malformation of the left lobe of his thyroid gland, 80×70×55mm in size, reaching retrosternally between the major arteries branching from his aortic arch and displacing his trachea 10mm to the right. In preparation for surgery, he underwent a radio-interventional procedure with embolisation of the arteries supplying the left lobe. This was followed by a lobectomy on the left via a partial sternotomy. The definitive histology result confirmed that the arteriovenous malformation was the benign cause of the mechanical neck syndrome. CONCLUSIONS: The case report presented here extends the differential diagnostic options in cases of mechanical neck syndrome. It describes a very rare disease of the thyroid gland, which prior to surgery may arouse suspicion of malignancy. It stresses the importance of close team cooperation between the endocrinologist, interventional radiologist and surgeon within the framework of preoperative diagnosis as well as preparation for surgery. Determination of the definitive histopathological diagnosis requires a pathologist experienced in such issues.