Iatrogenic pseudoaneurysm of the superior thyroid artery after thyroidectomy

INTRODUCTION: A pseudoaneurysm arising from the superior thyroid artery is extremely rare. To the best of our knowledge, STA Pseudoaneurysm after thyroidectomy has not been reported. CASE PRESENTATION: A 21-year-old female presented with anterior neck swelling of two years duration. Physical exam revealed a thyroid mass that measures 10 cm ∗ 8 cm. Neck US showed MNG (TIRADS 3) and FNAC suggested colloid goiter. Near Total Thyroidectomy was performed. On the 10th postoperative day, she noticed a painless, progressive left-sided neck swelling which is increasing in size with no active bleeding and no compressive symptoms. There is a 6x4cm tense pulsatile left-sided neck swelling adjacent to the thyroid cartilage and anterior to sternocleidomastoid muscle with a healed neck collar incision. CBC and coagulation profile were normal. Head and Neck CTA show aneurysmal dilatation of STA 3.8 cm × 3.2 cm with thrombosis of the posterior part of the lesion. CLINICAL DISCUSSION: STA Pseudoaneurysms are quite rare events but could lead to catastrophic complications. Clinical manifestations can include pulsating painful mass in the neck, dysphagia, dyspnea, bleeding from the oral cavity, and cerebrovascular symptoms. It should be investigated with Color Doppler ultrasound, MRI and CTA. CONCLUSION: In our case, the pseudoaneurysm occurred after thyroidectomy which has not been reported previously. The diagnosis was made by a computed tomography scan and the patient was treated by open STA ligation as endovascular service isn't available in our setup. Clinicians should therefore include pseudoaneurysm of STA or adjacent arteries in their differential diagnosis and intervene early to avoid devastating complications.