Inraoperative and Histological Visualization of Disrupted Vulnerable Plaques following Diagnostic Angiography of Moderate Carotid Stenosis

Abstract

Background. Digital subtraction angiography (DSA) remains an important tool for diagnosis of carotid stenosis but is associated with risk for periprocedural complications. This is the first report of direct intraoperative and histolopathologic visualization of DSA-related carotid plaque disruption. Case. A 64-year-old man diagnosed to have a 60% right carotid stenosis received diagnostic DSA for therapeutic decision-making. He developed transient left hand numbness and weakness immediately after the procedure. Intraoperative imaging during carotid endarterectomy revealed a fragile plaque with sharp surface laceration and intraplaque hemorrhage at the bifurcation. Microscopy of the specimen demonstrated a large atheromatous plaque with fibrous hypertrophy and intraplaque hemorrhage filled with recent hemorrhagic debris. Conclusion. The visualized carotid lesion was more serious than expected, warning the danger of embolization or occlusion associated with the catheter maneuvers. Thus the highest level of practitioner training and technical expertise that ensures precise assessment of plaque characteristics should be encouraged.

Figure 1

(a) B-mode ultrasound with color flow Doppler image on the longitudinal display of the carotid plaque with irregular surface. (b) The transverse display of the plaque at the carotid bifurcation. (c) ¹²³I-IMP SPECT transaxial slices of a patient with right ICA stenosis. MR angiography ((d) submental vertical projection; (e) lateral projection) with a hypoplastic or absent anterior and posterior communicating arteries.

Figure 2

(a) Peroperative common carotid angiogram (lateral projection) of a 64-year-old asymptomatic patient with a 60% stenosis of the right ICA by NASCET criteria (arrow). (b) Postoperative MR angiography confirmed disappearance of the stenosis. (c) Axial diffusion-weighted MR imaging of the brain immediately after the occurrence of neurologic events following the DSA. Ipsilateral hyperintense lesions are appreciable at the cortical-subcortical junction of right front-parietal lobes. (d) Postoperative diffusion-weighted imaging indicative of no ischemic lesions associated with CEA. Postoperative MR imagings ((b) and (d)) were performed on the next day after CEA.

Figure 3

(a) An intraoperative view of an atheromatous plaque originating from the proximal ICA during CEA with a shunt. (b) Magnified image revealing the sharp laceration of the plaque surface (black arrow) and intraplaque hemorrhage (white arrow). (c) Elastica-Masson stain matching histology cross section of the carotid plaque showing a large lateralized atheroma and intraplaque hemorrhage. A ditch shown in blue arrow suggests a part of the lacerating injury. Asterisks indicate the lumen.