To evaluate the correlation between maxLCBI4mm/FCTmin(a new index of lipid plaque based on NIRS-OCT technology) and fiber cap thickness , and the prognosis of patients, providing a new quantitative index for early, accurate and comprehensive identification of vulnerable plaques, and exploring preventive measures for adverse events such as cardiac death and recurrent myocardial infarction caused by vulnerable plaques, so as to improve the long-term prognosis of patients.

Inclusion Criteria:

1. 18 years old or older, gender is not limited
2. Patients with diabetes who require an OCT examination or treatment under OCT guidance (diabetes definition: active treatment with insulin or oral hypoglycemic agents at admission). For patients with diabetes who are treated with diet only, abnormal fasting blood sugar (>7 mmol/l), blood sugar >11.1 mmol/l at any time, or abnormal glucose tolerance tests based on World Health Organization standards need to be recorded.
3. Be able to understand the purpose of clinical research, voluntarily participate can complete the observation as required and sign the informed consent form

5: Lesion stenosis greater than or equal to 50% without interventional treatment

6: The diameter of the blood vessel in the diseased segment is greater than or equal to 2.5 mm

Exclusion Criteria:

• 1: Severe coagulation dysfunction (APTT greater than 3 times the upper limit of the normal range)

  2: Severe hemodynamic disorder or shock that cannot be corrected

  3: Patients with renal impairment（eGFR<30 mL/min/1.73m2）

  4: Severe symptoms of heart failure (NYHA III and above) or left ventricular ejection fraction <30%

  5: The presence or suspected presence of infective endocarditis or systemic active infection

  6: Patients with refractory ventricular arrhythmias who have previously undergone coronary bypass transplantation (CABG) or plan to undergo CABG during the study

  7: Patients with serious concurrent diseases such as advanced cancer have a life expectancy of less than 24 months

  8: Pregnant or lactating women, have a family plan within 24 months or are unwilling to take effective contraceptive measures

  9: The target vessel has severe calcification or severe tortuosity, which cannot be examined by OCT

  10: Have participated in other clinical trials or are participating in other drug/device clinical trials within 3 months prior to enrollment and have not met the primary endpoint

  11: Investigators believe that those who are unnecessary for OCT or not suitable for inclusion in this trial.

  12: There are multiple lesions in the same blood vessel, and the non-target lesion distance requiring treatment vascular segment is less than 5mm

Patients aged 18 years old or older ，with diabetes requiring an OCT examination or treatment under OCT guidance