Optical Coherence Tomography of Plaque Erosion and Thrombus in Severe Vertebral Artery Stenosis

A systematic review of application of frequency-domain optical coherence tomography in cerebral large artery atherosclerosis

AIMS

Frequency-domain optical coherence tomography (FD-OCT) is an emerging intravascular imaging modality that offers exceptional spatial resolution in interventional neuroradiology. We aimed to systematically review clinical studies on the applications of FD-OCT in cerebral large artery atherosclerosis (LAA).

METHODS

A systematic literature review of PubMed, Embase, and Cochrane Library was conducted to identify eligible studies published before 1 March, 2025. Eligible studies included all clinical articles written in English that reported the applications of FD-OCT in patients diagnosed with LAA.

RESULTS

A total of 50 studies with 1134 patients were included. FD-OCT was considered to be a feasible intravascular imaging modality as successful imaging could be achieved in 87.0% of patients with a 1.2% periprocedural complication rate. Unsuccessful FD-OCT imaging was attributed primarily to its current limitations, particularly inadequate blood clearance and failure to navigate the tortuous cerebrovascular anatomy or stenosis. The majority of the included studies (35/50) employed FD-OCT to evaluate extracranial atherosclerotic stenosis. FD-OCT could better stratify subsequent stroke risk by adequately identifying features of plaque vulnerability such as thin-cap fibroatheroma, neovascularization, and cholesterol crystal. Through accurately assessing stent-vessel interaction, FD-OCT has the potential to guide the selection of tailored interventions during carotid artery stenting. Recent research (10/50) has shown its potential utility for intracranial atherosclerotic stenosis, including culprit lesion differentiation, peri-intervention evaluation, and mechanistic insight into pathophysiology of stenosis and in-stent restenosis. As for acute ischemic stroke, FD-OCT following thrombectomy can potentially guide the selection of tailored adjunctive treatments to optimize clinical outcomes by assessing the intrinsic properties of the culprit lesion.

CONCLUSIONS

FD-OCT has emerged as a valuable intravascular imaging tool for evaluating the intrinsic properties of culprit lesions and stent-vessel interactions, showing substantial potential in the diagnosis, evaluation, and treatment of cerebral LAA.

Panvascular concept in the evaluation and treatment of intracranial atherosclerotic stenosis

Cerebrovascular disease is the leading causes of death and disability worldwide. Intracranial atherosclerotic stenosis (ICAS) is one of the major causes of ischemic stroke, especially in the Asian population. It is urgent to explore effective screening methods for early diagnosis to improve prognosis of patients with ICAS. Recently, the concept of panvascular medicine has provided a direction for the exploration of evaluation of ICAS. Based on the concept of "panvascular medicine," atherosclerosis is the common pathological feature of panvascular disease, such as ICAS and coronary artery disease (CAD). In-depth research on the formation and development of plaques, the development and application of more precise preoperative assessment and detection methods, and the utilization of new interventional equipment have greatly enhanced the precision of diagnosis and treatment of CAD. Studies attempt to apply similar evaluation and treatment in ICAS. The deeper understanding, the more accurate diagnosis and treatment, contributing to improve the prognosis of patients with ICAS. This review focuses on these evaluations and treatment of CAD applied in the field of ICAS.

Optical Coherence Tomography in the Evaluation of Suspected Carotid Webs

BACKGROUND

Carotid web (CaW) is a subtype of fibromuscular dysplasia that predominantly involves the intimal layer of the arterial wall and is commonly overlooked as a separate causative entity for recurrent strokes. CaW is defined as a shelf-like lesion at the carotid bulb, although different morphological features have been reported. Optical coherence tomography (OCT) has been described in the literature as a useful microscopic and cross-sectional tomographic imaging tool. This study aimed to evaluate the potential utility of OCT in characterizing the wall structure features of patients with suspected CaW.

METHODS

Retrospective analysis of patients with suspected CaW who underwent digital subtraction angiography (DSA) coupled with OCT of the carotid bulb from 2018 to 2021 in a single comprehensive stroke center.

RESULTS

Sixteen patients were included. The median age was 56 years (IQR 46-61) and 50% were women. OCT corroborated the diagnosis of CaW in 12/16 (75%) cases and ruled it out in 4/16 (25%) patients in whom atherosclerotic disease was demonstrated. Five of the 12 lesions demonstrated a thick fibrotic ridge consistent with CaW but also showed atherosclerotic changes in the vicinity of the carotid bulb (labeled as "CaW+"). In 4/16 (25%) patients, microthrombi adhered to the vessel wall were noted on OCT (inside the CaW pocket or just distal to the web), none of which were observed on CT angiography or DSA.

CONCLUSIONS

OCT may have value as a complementary imaging tool in the investigation of patients with suspected CaW and atypical morphological features. Further studies are warranted.

Optical Coherence Tomography in Cerebrovascular Disease: Open up New Horizons

Optical coherence tomography (OCT), based on the backscattering or reflection of near-infrared light, enables an ultra-high resolution of up to 10 μm. The successful application of OCT in coronary artery diseases has sparked increasing interest in its implementation in cerebrovascular diseases. OCT has shown promising potential in the atherosclerotic plaque structure characterization, plaque rupture risk stratification, pre-stenting and post-stenting evaluation, and long-term follow-up in extracranial and intracranial atherosclerotic stenosis (ICAS). In hemorrhagic cerebrovascular diseases, OCT plays an important role in the structure evaluation, rupture risk stratification, and healing and occlusion evaluation following initial treatment in intracranial aneurysms (IAs). In this study, we summarized the applications of OCT in the diagnosis, treatment, and follow-up of cerebrovascular diseases, especially in ICAS and IAs. The current limitations and future directions of OCT in the endovascular treatment of cerebrovascular diseases were also discussed.