Penile Cutaneous Temperature in Systemic Sclerosis: A Thermal Imaging Study

Systemic Sclerosis is a connective tissue disorder featuring vascular alterations and an immunological activation leading to a progressive and widespread fibrosis of several organs such as the skin, lung, gastrointestinal tract, heart and kidney. Moreover men with systemic sclerosis (SSc) present an increased risk of developing erectile dysfunction (ED). Recently, we evaluated the extent of penile vascular damage in sclerodermic patients using Duplex ultrasonography. The aim of this paper is to investigate whether penile thermal differences exist between sclerodermic patients and healthy controls. For this reason 10 men with SSc receiving current treatment for their disease, and 10 healthy controls were enroled; penile thermal properties were assessed through non-contact thermal imaging (functional Infra Red Imaging fIRI); erectile function was evaluated using the sexual health inventory for men (SHIM) questionnaire. The SHIM results confirmed the presence of ED in sclerodermic patients. Baseline penile temperature in patients (32.1 ± 1.4°C) was lower than in controls (34.1 ± 0.9°C). Recovery from cooling test was seen to be faster in healthy controls than in patients, both in terms of recovery amplitude (patients 3.75 ± 2.09°C, controls 9.80 ± 2.77°C) and amplitude to time constant ratio (patients 1.21 ± 0.64°C/min, controls 1.96 ± 0.48°C/min). These results show that penile thermal abnormalities occur in almost all sclerodermic patients. Non-contact thermal imaging not only identifies thermal alterations but also clearly distinguishes between SSc patients and healthy controls and therefore could represent a valuable instrument in identifying early ED in SSc patients.

Combined thermal and laser Doppler imaging in the assessment of cutaneous tissue perfusion

Infrared thermal imaging permits to non-invasively obtain, throughout bioheat models using a series of thermal images, the cutaneous blood perfusion. Laser Doppler imaging measures blood flow in the very small blood vessels of the microvascular network. In this paper, we compare findings from the two methods on a set of healthy volunteers. Cutaneous blood perfusion values obtained from thermal imaging correlate to those obtained by means of Laser Doppler imaging with the advantage of a better time resolution. Combined imaging of the two modalities may provide a useful tool for monitoring diseases affecting cutaneous tissue and/or microcirculation.

Superimposition of thermal imaging to visual imaging using homography

InfraRed Thermal Imaging (IR) permits to non-invasively map the skin temperature distribution of the human body. Combining together thermal and visual imaging enriches the informative content of IR images and provides to the physician an anatomically-based and more friendly visualization--on the thermal images--of the presence of possible pathological processes. In this paper we use a homography technique to overlap a thermal image to a visible one. The technique provides an effective pixel-to-pixel correspondences between the two images or their portions.

Monitoring skin temperature in trained and untrained subjects throughout thermal video

Skin temperature was monitored during a graded exercise to verify whether trained individuals have different skin thermoregulation from untrained ones. Eighteen subjects (10 trained; 8 untrained) were studied recording thermal videos of their skin temperature during the exercise. Training level was assessed by maximal oxygen uptake measurements. Trained individuals have better skin thermal control than untrained.