Determination of IRTI (infrared thermal imaging) can be used to evaluate PAD patients with critical limb ischemia with different degrees of lesion.

IRTI can be used to evaluate the foot blood perfusion after percutaneous transluminal angioplasty (PTA) treatment and determine the success rate of surgery.

IRTI can be used as an effective follow-up tool for patients after surgery.

Inclusion Criteria:

• Patients with Rutherford grade 3, 4, 5, or 6.
• Patients with indications for lower extremity arterial PTA: severe intermittent claudication, rest pain, ulceration or gangrene.
• Patients who required PTA of only one limb (left versus right).

Exclusion Criteria:

• Patients with body temperature above 37 ° C.
• Patients with indications for open surgery.
• Patients requiring major amputation (above the ankle).
• Patients with acute occlusive or embolic limb ischemia.
• Patients with deep venous thrombosis of the lower extremity.

PAD patients who came to our hospital for diagnosis and treatment were initially selected, and those who met the indications for PTA surgery were finally included in the study.