Identification of near-occlusive carotid plaques by indocyanine green video angiography during carotid endarterectomy

Objective To investigate the effect of indocyanine green video angiography on the identification of near-occlusive carotid plaques during carotid endarterectomy.Methods A total of 66 patients with nearly occluded carotid arteries (≥95% stenosis) who were treated in the Affiliated Hospital of Xuzhou Medical University from January 2020 to May 2023 were selected and their clinical data were retrospectively analyzed. According to the use of indocyanine green before carotid dissection during the operation, the patients were divided into two groups: an indocyanine green (ICG) group and a non-ICG group. Head and neck CT angiography (CTA) was performed before the operation to check the site and extent of stenosis, while cranial magnetic resonance imaging (MRI) was applied for examining acute ischaemic cerebral infarction. In the ICG group, indocyanine green video angiogram was used to visualize the proximal and distal ends of the plaque in the carotid artery prior to carotid dissection, and after stripping the plaque and suturing the carotid artery, a second angiogram was taken to determine the clearance of carotid stenosis. Additional head and neck CTA was examined within 7 days after surgery. Both groups were compared for the differences in identifying carotid plaques at the proximal and distal segments and prognosis.Results Among the 66 patients, there were 35 patients were in the ICG group and 31 were in the non-ICG group. There was no statistical difference between the two groups in clinical data such as gender, age, hypertension, diabetes and coronary artery disease (P>0.05). In the ICG group, plaques at the proximal and distal segments were identified in 32 and 29 cases, respectively. In the non-ICG groups, plaques at the proximal and distal segments were identified in 12 and 9 cases, respectively. The ICG group was superior to the non-ICG group in identifying the plaques at the proximal and distal segments, with statistical difference (P<0.01). Preoperative head and neck CTA demonstrated that 7 patients had high carotid stenosis. After intraoperative plaque removal and suturing of the vessel, 62 patients showed carotid plaque clearance and smooth blood flow by indocyanine green video angiography. Three patients developed cerebral infarction after surgery and improved after conservative treatment. The remaining 63 patients showed no significant symptoms after surgery.Conclusions Indocyanine green video angiography during carotid endarterectomy is effective in identifying nearly-occluded carotid plaques, and is a viable method to improve surgical outcomes by allowing intraoperative determination of the site of stenosis, plaque removal and vessel patency, which can guide surgical operations to a certain extent.