In carotid artery stenting (CAS), iodinated contrast medium is generally required, however, iodinated contrast medium is hard to use for the patient of renal failure and iodine allergy. In 9 carotid artery stenosis in 8 patients with chronic renal failure and iodine allergy. CAS was performed guided by carotid ultrasound and intravascular ultrasound (IVUS) without use of the iodinate contrast medium. Ultrasound was useful for crossing the guidewire, decision of the position of the stent, evaluation of the in-stent plaque protrusion, and measurement of peak systolic velocity (PSV) in the stenotic lesion and the deployed stent. Pre- and post-operative mean PSV measured by ultrasound were 235 ± 115 and 99 ± 42 cm/s, respectively. Ultrasound-guided CAS is therefore suitable for patients with renal failure and iodine allergy, except for cases involving high position, elongated carotid artery stenosis.
A 71-year-old woman was admitted to our hospital with an acute Stanford type A aortic dissection. She underwent tricuspid valve plasty and ascending aorta repair. On day 7 she presented with aphasia. Brain computed tomography (CT) revealed a low-density area in the left frontal lobe. Carotid Doppler ultrasonography disclosed that the left common carotid artery was occluded up to a point just proximal to the carotid bifurcation, and retrograde flow was seen from the external carotid artery (ECA) to the internal carotid artery via the carotid bifurcation. These findings suggested a collateral anastomosis between the ECA and the vertebral artery. Four-dimensional CT angiography is sufficiently effective for evaluation of occipital-vertebral anastomosis.
A 40-year-old man with a history of carotid artery stenting for symptomatic left internal carotid artery (ICA) dissection presented to our hospital to undergo treatment for spontaneous asymptomatic right internal carotid artery (ICA) dissection. Carotid angiogram revealed the dissection of the right ICA and formation of a dissecting aneurysm with a false lumen with blood flow. Transoral carotid ultrasonography (TOCU) revealed the entry and re-entry points of the false lumen with high blood flow, and the true lumen was stenosed secondary to the expanded false lumen. Carotid artery stenting of the right ICA was performed. Postoperative TOCU revealed loss of blood flow in the thrombosed false lumen, and the true lumen was expanded satisfactorily with no stenosis. TOCU allows evaluation of the extracranial ICA, which is not possible with conventional carotid artery ultrasonography. Our case suggests that pre- and post-evaluation by TOCU for carotid artery stenting in ICA dissection appears effective.
Background: Intraplaque neovascularization in carotid artery plaque was assessed using contrast-enhanced ultrasonography (CEUS) and then the patient underwent carotid endarterectomy (CEA). Significant contrast flow was detected in the plaque and the findings from a pathological specimen are discussed. Case: Asymptomatic severe left-sided carotid stenosis was detected by ultrasonography (US) in a 71-year-old man, and the patient underwent CEA. We assessed the contrast effects of perﬂubutane over time in CEUS. A pathological specimen of plaque selected during CEA was stained with Masson’s trichrome and immunostained using CD34 and CD146. Considerable inflow of contrast from the lumen to the plaque was observed on CEUS, and the plaque was entirely enhanced with contrast agent over time. The pathological findings of the specimen excised by CEA showed a connection between the vessel lumen and nearby neovascularization throughout the plaque. Conclusion: The inflow of contrast agent into the plaque on CEUS corresponded with a histopathological finding of the neovascularization.