Asymptomatic Complete Occlusion of Extracranial Internal Carotid Artery: A Case Report

This article reports on head-and-neck computed tomography angiography imaging findings and data of ultrasound examination of the extracranial carotid and vertebral arteries of 69-year-old patient with unilateral asymptomatic complete occlusion of extracranial internal carotid artery (ICA) in combination with unusually elongated styloid processes of temporal bone. The aim of the study was to specify the collateral pathways blood supply to the brain and to assess the possible clinical significance of an abnormally elongated styloid pro cess. Adequate cerebral blood flow was provided by anastomoses between the arteries at the base of the brain. This can explain the asymptomatic unilateral complete occlusion of the extracranial ICA. Occlusion of the artery was not associated with the presence of a 5.5 cm styloid process. Computed tomography angiography is a highly informative method for visualizing the individual morphological variants to clarify their clinical significance.

High-flow bypass surgery using a radial artery graft for an extracranial internal carotid artery aneurysm: Case reports and literature review

Background: Extracranial carotid artery aneurysms are rare. Surgery may be difficult when vessels are tortuous and on a high cervical level. We report two patients whose tortuous extracranial internal carotid artery (ICA) aneurysm located on a high cervical level was successfully treated by ICA ligation and a high-flow bypass using a radial artery (RA) graft between the external carotid- and the middle cerebral artery. Case Description: (Case 1) A 47-year-old man suffered a recurrent cerebral infarct despite medical treatment. His right extracranial ICA aneurysm measured 33 mm; it was tortuous and located at a high cervical level. We ligated the ICA after placing a high-flow bypass using an RA graft. The aneurysm was not repaired. (Case 2) A 59-year-old woman noticed pulsatile swelling on her left neck. It was due to an extracranial ICA aneurysm that was large (36 mm), tortuous, and located at a high cervical level. We performed ICA ligation after placing a high-flow bypass using an RA graft without direct aneurysmal repair. Six months after the operation she noted a pulsatile bulge on the left oropharynx. We confirmed recurrence of an aneurysm from retrograde blood flow and performed internal trapping by occluding the distal portion of the ICA aneurysm using an intravascular procedure. Conclusion: ICA ligation after placing a high-flow bypass with an RA-graft is a technically demanding, but safe procedure to address extracranial ICA aneurysms that are tortuous and located at a high cervical level.

Clinical Significance of Ultrasound-Based Hemodynamic Assessment of Extracranial Internal Carotid Artery and Posterior Cerebral Artery in Symptomatic and Angiographic Evolution of Moyamoya Disease: A Preliminary Study

Objective: To investigate the hemodynamic changes using ultrasound according to digital subtraction angiography (DSA) findings and explore the association between ultrasound parameters and clinical symptoms of moyamoya disease (MMD).Methods: Hemodynamic parameters of extracranial internal carotid artery (EICA) and posterior cerebral artery (PCA) were evaluated by ultrasound. According to DSA findings, EICA parameters among Suzuki stages (stage I-II, III-IV, and V-VI), and PCA parameters among leptomeningeal system scores (score 0–2, 3–4, and 5–6) were compared, respectively. ROC analysis was performed based on the ultrasound parameters to distinguish stroke from non-stroke patients.Results: Forty patients with MMD were included in our study (16 men; median age, 37 years). The diameter (D), peak systolic velocity (PSV), end diastolic velocity (EDV) and flow volume (FV) of EICA decreased as the Suzuki stage advanced (D: P < 0.001; PSV: P < 0.001; EDV: P < 0.001; FV: P < 0.001). The PSV and EDV of PCA increased as the leptomeningeal system scores advanced (PSV: P < 0.001; EDV: P < 0.001). ROC analysis showed that the area under the curves (AUCs) based on the D and FV of EICA, the PSV and EDV of PCA and their combination were 0.688, 0.670, 0.727, 0.684, and 0.772, respectively, to distinguish stroke from non-stroke patients.Conclusions: Ultrasound parameters were related to Suzuki stages and leptomeningeal system scores. Ultrasound may be useful in predicting the occurrence of stroke in patients with MMD. Future prospective studies with large sample sizes and long-term follow-up are needed to confirm our preliminary findings.