Differential Diagnosis and Treatment Outcomes of Tumors at the Carotid Bifurcation

Functional Compression of the Right Internal Carotid Artery by the Hyoid Bone in a Patient with Moyamoya Syndrome and Low Internal Carotid Artery Bifurcation: A Case Report

Background

Functional compression of the internal carotid artery by hyoid bone is a rare but potentially serious condition that can lead to vascular complications, particularly when coexisting with intracranial vascular abnormalities. This case report describes a 48-year-old woman with acute cerebral ischemia due to a combination of functional right internal carotid artery compression by the hyoid bone, low carotid bifurcation, and coexisting Moyamoya syndrome.

Case Report

In this article, we describe the clinical case of a 48-year-old woman who presented with sudden-onset weakness in her left arm. Imaging studies demonstrated acute ischemia in the territory supplied by the right middle cerebral artery. Further evaluation with computed tomography angiography revealed compression of the right internal carotid artery by the hyoid bone. However, additional imaging studies, including digital subtraction angiography and carotid Doppler ultrasound, did not reveal any signs of internal carotid artery stenosis. This suggested that the compression was functional, occurring only in specific positions of the head or arms. The patient was also newly diagnosed with Moyamoya syndrome, characterized by progressive stenosis of the intracranial vessels. Prompt recognition of these findings enabled timely management, including the initiation of antiplatelet therapy.

Conclusion

In cases of acute brain ischemia, it is crucial to consider both intracranial and extracranial vascular conditions. This case report underscores the significance of identifying anatomical variations in the relationship between the hyoid bone and the internal carotid artery, as it can lead to arterial compression and potentially trigger acute ischemic strokes, especially in combination with Moyamoya syndrome. Understanding these anatomical nuances is essential for early diagnosis and appropriate management.

Clinical outcomes and challenges of surgical extirpation for carotid body paraganglioma in South Korea: a single-center retrospective study

BACKGROUND

Carotid body paraganglioma (CBP) is a rare, highly vascularized, and slow-growing neuroendocrine tumor. Surgical resection is the definitive treatment for CBP, however, it remains challenging due to the tumor's proximity to critical blood vessels and cervical cranial nerves. This study aimed to document the characteristics of CBP and examine the clinical outcomes of patients following surgical extirpation of CBP.

METHODS

This is a single-center retrospective review analyzed patients who underwent CBP extirpation. We examined the patient demographics, preoperative clinical features, tumor characteristics, levels of catecholamines and their metabolites in the serum and urine. Surgeries were performed by one vascular surgeon with follow-ups at 1,3,6 months and yearly thereafter. Logistic regression analysis was conducted to identify risk factors associated with the occurrence of either permanent or temporary cervival cranial nerve palsy (CNP).

RESULTS

From September 2020 to February 2023, this study examined 21 cases of CBP removal surgeries that were carried out in 19 patients. The mean age of the patients was 38.9 ± 10.9 years and the percentage of males was 57.1% (n = 12). The most common preoperative clinical feature was painless neck mass (n = 12; 57.1%). Complete resection was achieved in 20 cases; excluding one case with pathologically proven sclerosing paraganglioma. Vascular procedures were performed in four cases (ECA resection, n = 2; primary repair of ICA tear without carotid shunting, n = 1; and ICA patch angioplasty with carotid shunting, n = 1). Temporary cranial neurologic complications, specifically aspiration and hoarseness occurred in four (19.0%), and three (14.3%) cases, respectively. Hoarseness associated with permanent CNP persisted for more than 6 months in two cases (9.5%). No recurrence or mortality was observed during the follow-up period.

CONCLUSIONS

Surgical resection is the primay treatment approach for CBP; however, it poses risks of vascular or cervical CNP. The intraoperative estimated blood loss was the only identified risk factor for CNP.

Malignant carotid body tumors: What we know, what we do, and what we need to achieve. A systematic review of the literature

Malignant carotid body tumors (MCBT) are rare and diagnosed after detection of nodal or distant metastases. This systematic review (SR) focuses on MCBT initially approached by surgery. Preferred Reporting Items for SR and Meta-Analysis (MA) guided the articles search from 2000 to 2023 on PubMed, Scopus, and Web of Science. Among 3548 papers, 132 (337 patients) were considered for SR; of these, 20 (158 patients) for MA. Malignancy rate was 7.3%, succinate dehydrogenase (SDH) mutation 17%, age at diagnosis between 4th and 6th decades, with a higher prevalence of females. MCBTs were mostly Shamblin III, with nodal and distant metastasis in 79.7% and 44.7%, respectively. Malignancy should be suspected if CBT >4 cm, Shamblin III, painful or otherwise symptomatic, at the extremes of age, bilateral, with multifocal disease, and SDHx mutations. Levels II-III clearance should be performed to exclude nodal metastases and adjuvant treatments considered on a case-by-case basis.