Department of Internal Medicine, Taoyuan General Hospital, Taoyuan, Taiwan.
J Vasc Surg. 2011 Oct;54(4):1074-80. doi: 10.1016/j.jvs.2011.03.287. Epub 2011 Jul 23.
We investigated the usefulness of infrared thermography in evaluating patients at high risk for lower extremity peripheral arterial disease (PAD), including severity, functional capacity, and quality of life.
A total of 51 patients (23 males; age 70 ± 9.8 years) were recruited. They completed three PAD-associated questionnaires, including walking impairment, vascular quality of life, and 7-day physical activity recall questionnaires before a 6-minute walking test (6MWT). Ankle-brachial index (ABI) and segmental pressure were analyzed for PAD diagnosis and stenotic level assessment. The cutaneous temperature at shin and sole were recorded by infrared thermography before and after the walk test. Detailed demographic information and medication list were obtained.
Twenty-eight subjects had abnormal ABI (ABI <1), while PAD was diagnosed in 20. No subjects had non-compressible artery (ABI >1.3). Demographic profiles and clinical parameters in PAD and non-PAD patients were similar, except for age, smoking history, and hyperlipidemia. PAD patients walked shorter distances (356 ± 102 m vs 218 ± 92 m; P < .001). Claudication occurred in 14 patients, while seven failed in completing the 6MWT. The rest temperatures were similar in PAD and non-PAD patients. However, the post-exercise temperature dropped in the lower extremities with arterial stenosis, but was maintained or elevated slightly in the extremities with patent arteries (temperature changes at sole in PAD vs non-PAD patients: -1.25 vs -0.15°C; P < .001). The exercise-induced temperature changes at the sole were not only positively correlated with the 6MWD (Spearman correlation coefficient = 0.31, P = .03), but was also correlated with ABI (Spearman correlation coefficient = 0.48, P < .001) and 7-day physical activity recall scores (Spearman correlation coefficient = 0.30, P = .033).
By detecting cutaneous temperature changes in the lower extremities, infrared thermography offers another non-invasive, contrast-free option in PAD evaluation and functional assessment.
本研究旨在探讨红外热成像技术在评估下肢外周动脉疾病（PAD）高危患者中的应用价值，包括疾病严重程度、功能能力和生活质量。
共纳入 51 例患者（23 例男性；年龄 70 ± 9.8 岁），这些患者完成了 3 项与 PAD 相关的问卷，包括行走障碍问卷、血管生活质量问卷和 7 天身体活动回顾问卷，随后进行 6 分钟步行试验（6MWT）。ABI 和节段压力分析用于 PAD 诊断和狭窄程度评估。在步行试验前后，通过红外热成像记录小腿和足底的皮肤温度。同时还收集了详细的人口统计学信息和用药清单。
28 例患者 ABI 异常（ABI<1），20 例患者诊断为 PAD。无患者出现无脉（ABI>1.3）。PAD 患者与非 PAD 患者的人口统计学特征和临床参数相似，除年龄、吸烟史和高脂血症外。PAD 患者的步行距离更短（356 ± 102 m 比 218 ± 92 m；P<0.001）。14 例患者出现跛行，7 例患者未能完成 6MWT。PAD 患者与非 PAD 患者的静息温度相似。然而，在下肢动脉狭窄患者中，运动后下肢温度下降，但在动脉通畅的下肢，温度仅略有下降或保持不变（PAD 患者与非 PAD 患者足底温度变化：-1.25 比-0.15°C；P<0.001）。足底运动后温度变化不仅与 6MWD 呈正相关（Spearman 相关系数=0.31，P=0.03），而且与 ABI（Spearman 相关系数=0.48，P<0.001）和 7 天身体活动回顾评分（Spearman 相关系数=0.30，P=0.033）也呈正相关。
通过检测下肢皮肤温度变化，红外热成像技术为 PAD 评估和功能评估提供了另一种非侵入性、无对比剂的选择。
