Plantar thermography is useful in the early diagnosis of diabetic neuropathy

Abstract

OBJECTIVES:This study evaluated plantar thermography sensitivity and specificity in diagnosing diabetic polyneuropathy using cardiac tests (heart rate variability) as a reference standard because autonomic small fibers are affected first by this disease.METHODS:Seventy-nine individuals between the ages of 19 and 79 years old (28 males) were evaluated and divided into three groups: control (n = 37), pre-diabetics (n = 13) and type 2 diabetics (n = 29). The plantar images were recorded at baseline and then minutes after a provocative maneuver (Cold Stress Test) using an infrared camera that is appropriate for clinical use. Two thermographic variables were studied: the thermal recovery index and the interdigital anisothermal technique. Heart rate variability was measured in a seven-test battery that included three spectral indexes (in the frequency domain) and four Ewing tests (the Valsalva maneuver, the orthostatic test, a deep breathing test, and the orthostatic hypotension test). Other classically recommended tests were applied, including electromyography (EMG), Michigan inventory, and a clinical interview that included a neurological physical examination.RESULTS:Among the diabetic patients, the interdigital anisothermal technique alone performed better than the thermal recovery index alone, with a better sensitivity (81.3%) and specificity (46.2%). For the pre-diabetic patients, the three tests performed equally well. None of the control subjects displayed abnormal interdigital anisothermal readouts or thermal recovery indices, which precluded the sensitivity estimation in this sample of subjects. However, the specificity (70.6%) was higher in this group.CONCLUSION:In this study, plantar thermography, which predominately considers the small and autonomic fibers that are commonly associated with a sub-clinical condition, proved useful in diagnosing diabetic neuropathy early. The interdigital anisothermal test, when used alone, performed best.

The identification of higher forefoot temperatures associated with peripheral arterial disease in type 2 diabetes mellitus as detected by thermography

“…This ensured that the comparison being made was between diabetes participants with normal perfusion (and no neuropathy) and those with peripheral arterial disease (and no neuropathy). All participants with neuropathy were excluded as it is known that peripheral neuropathy tends to result in warmer feet [26]. It is standard clinical practice to palpate a patient's limbs to detect temperature differences with a cooler limb normally being interpreted as possible evidence of ischaemia in that limb.…”

Plantar pressure and foot temperature responses to acute barefoot and shod running

“…For example, acute injuries such as skin blisters may promote increases in foot temperature after running (as a result of friction forces during foot contact with the ground) [7]. In addition, skin temperature was recently suggested as a diagnostic criterion in detection of charcot arthropathy and neuropathic ulcers in diabetics [8,9]. The aforementioned literature suggests skin temperature to be an important variable in the study of the foot stress and its relationship with injury risk.…”

Human Tongue Thermography Could Be a Prognostic Tool for Prescreening the Type II Diabetes Mellitus

“…is insignificance might be due to the thicker white coating in the middle region of the diabetic tongue. e classification of normal and diabetic neuropathy using plantar thermograms by interdigital isothermal technique was observed to have 81.3% and 46.2% as sensitivity and specificity [64]. e sensitivity of foot thermogram for screening the osteomyelitis was found to be 60% and observed increased skin surface temperature distribution in periwound ankle and knee areas of diabetic foot [65].…”