Imaging Pearls ❯ Vascular ❯ Paragangliomas
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- “While the majority of cases are sporadic, approximately 40% are thought to be hereditary. These familial tumors tend to occur earlier than their sporadic counterparts, with a peak prevalence of 30–35 years of age. Additionally, familial paragangliomas are more commonly multicentric than sporadic tumors. Paragangliomas of the head and neck are more common in females, with this predilection most common in jugular (3:1) and tympanic subtypes (6:1). Paragangliomas are associated with multiple syndromes and genes and are commonly seen in patients with von Hippel-Lindau (VHL), neurofibromatosis type I (NF I), and multiple endocrine neoplasia type II (MEN II).”
Multimodality imaging of paragangliomas of the head and neck
Jarett Thelen and Alok A. Bhatt
Insights into Imaging (2019) 10:29 - “On computed tomography (CT), paragangliomas present as a well-defined soft tissue attenuation mass. They most commonly demonstrate homogenous, avid enhancement after administration of intravenous contrast, though heterogeneity can occur in lesions with intratumoral thrombosis or hemorrhage. Additionally, paragangliomas may cause local erosion of adjacent bony structures, and CT imaging is excellent for evaluation of osseous involvement.”
Multimodality imaging of paragangliomas of the head and neck
Jarett Thelen and Alok A. Bhatt
Insights into Imaging (2019) 10:29 - “Carotid body paragangliomas are the most common paragangliomas within the head and neck, accounting for approximately 60% of all cases. The majority of cases occur in older patients, ranging from 40 to 70 years of age with a median age of 57. As their name suggests, they arise from the carotid body, a grouping of chemoreceptors which reside between the internal and external carotid arteries at the bifurcation of the common carotid artery. The carotid body provides regulatory function for both oxygenation, carbon dioxide, and pH within the blood. Carotid body tumors classically present as slow-growing, painless swelling in the lateral neck, often laterally mobile but fixed vertically (known as Fontaine’s sign). As the tumor grows within the carotid space, it can compress the adjacent nerves (most commonly the vagus nerve), resulting in symptoms such as dysphagia, hoarseness, or Horner’s syndrome.”
Multimodality imaging of paragangliomas of the head and neck
Jarett Thelen and Alok A. Bhatt
Insights into Imaging (2019) 10:29 - “Associated mass effect classically results in splaying of the internal and external carotid arteries, resulting in the characteristic “lyre sign”, rather than displacing them together. Differential considerations when encountering a mass in this location include schwannomas and neurofibromas; however, these tumors are generally less vascular and should not demonstrate the characteristic flow voids seen in paragangliomas. Additionally, hypervascular metastases such as those seen with primary renal or thyroid malignancy should be considered.”
Multimodality imaging of paragangliomas of the head and neck
Jarett Thelen and Alok A. Bhatt
Insights into Imaging (2019) 10:29 - “CBT can be found at any age and is frequently seen in those between 50 and 70 years old (range, 18–94 years), with slightly higher prevalence in women than men (male-to-female ratio of 1:1.9). Bilateral disease is significantly more frequent in familial (31.8% of cases) than in non-familial CBT (4.4%).”
Carotid body tumor: a case report and literature review.
Hoang VT et al.
J Radiol Case Rep. 2019 Aug 31;13(8):19-30 - “CBTs usually manifests as an asymptomatic anterior neck mass. In larger tumors, they can be associated with the myriad of presenting symptoms of a space-occupying lesion in this location, such as fullness, pain, dysphagia, odynophagia, hoarseness, and stridor. The tissue is often rubbery, firm, and noncompressible. The mass may be displaced laterally but not vertically. Generally, a palpable thrill or bruit may be absent if the tumor is small. Historically, cranial nerve deficits were present in approximately 10% of patients secondary to nerve compression; however with improved imaging modalities, CBTs are detected earlier at smaller sizes, and thereby cranial nerve compromise is rare currently. Lastly, a rare functional CBT may produce neuroendocrine secretions causing catecholamine-related symptoms, such as palpitations, headaches, hypertension, tachycardia, or flushing .”
Carotid body tumor: a case report and literature review.
Hoang VT et al.
J Radiol Case Rep. 2019 Aug 31;13(8):19-30 - “Differential diagnosis of CBTs should be distinguished from masses in the neck or the lesions originating from the carotid space. The most important differential diagnosis include aneurysm or pseudoaneurysm of the carotid artery, hematoma, glomus vagale tumor, and vagal schwannoma. In addition to these, carotid body hyperplasia should also be remembered. It may develop on account of chronic hypoxia and is primarily described in patients living at high altitudes .”
Carotid body tumor: a case report and literature review.
Hoang VT et al.
J Radiol Case Rep. 2019 Aug 31;13(8):19-30