Differential Diagnosis for Pulsatile Mass in Right Side of Neck

• Single Most Likely Diagnosis
  • Carotid artery aneurysm: This is a likely diagnosis due to the pulsatile nature of the mass, which suggests a vascular origin. The carotid artery is a common site for aneurysms, and its location in the neck makes it a plausible cause for a pulsatile mass.
• Other Likely Diagnoses
  • Carotid body tumor: This is a type of paraganglioma that occurs at the bifurcation of the carotid artery and can present as a pulsatile mass in the neck.
  • Thyroid artery aneurysm: Although less common, aneurysms of the thyroid arteries can also cause pulsatile masses in the neck.
  • Vascular malformation: Abnormal formations of blood vessels, such as arteriovenous malformations (AVMs), can present as pulsatile masses.
• Do Not Miss Diagnoses
  • Carotid artery dissection: This is a serious condition where there is a tear in the wall of the carotid artery, which can lead to stroke or death if not promptly diagnosed and treated.
  • Ruptured carotid aneurysm: A ruptured aneurysm can lead to severe bleeding, stroke, or death, making it crucial not to miss this diagnosis.
• Rare Diagnoses
  • Neurofibromatosis with vascular involvement: In rare cases, neurofibromatosis type 1 can involve the blood vessels, leading to aneurysms or vascular malformations that might present as a pulsatile mass.
  • Pheochromocytoma with vascular involvement: Although primarily known as a tumor of the adrenal gland, pheochromocytomas can rarely occur in extra-adrenal sites, including the neck, and may be associated with vascular abnormalities.