M. Proietti

Infrared functional imaging applied to Raynaud's phenomenon

Presents an approach that allows simultaneous assessment of thermal properties of multiple fingers on both hands. It is a novel approach to the estimation of Raynauds phenomenon based on infrared functional imaging assessments. Q, which represents the total amount of stored heat by the finger during the rewarming processes and is evaluated by means of the area under the time-temperature curve, seems to be particularly effective in order to describe the thermal recovery capabilities of the finger, also in terms of thermal efficiency. Q clearly highlights the difference between primary Raynauds phenomenon and secondary scleroderma patients, and between patients and normal as well, and provides useful information about the abnormalities of their thermoregulatory finger properties.

Significant changes of peripheral perfusion and plasma adrenomedullin levels in N-acetylcysteine long term treatment of patients with sclerodermic Raynauds phenomenon.

The unclear pathogenesis of scleroderma vascular lesions makes treatment of Raynauds phenomenon (RP) in Systemic Sclerosis (SSc) patients very difficult and a new effective treatment is requested. Recently, a powerful antioxidant agent, the N-acetylcysteine (NAC) has been shown to decrease the frequency and severity of RP in SSc patients. Subsequently, using functional infrared imaging, we showed that a single 1-hour NAC infusion in these patients caused a significant increase of skin temperature. The aim of this study was to demonstrate the efficacy of long term therapy with NAC in an open, clinical trial evaluating clinical, instrumental and laboratory parameters. Patients started the treatment receiving for two years, from October to May, intravenous NAC infusions of 15 mg/kg per hour each, for 5 consecutive hours, every two weeks. Before and after each infusion, patients underwent both Laser Doppler perfusion Imaging (LDPI) for the evaluation of the digital perfusion and a blood test to ascertain the plasma adrenomedullin (AM) levels. The NAC infusion increased global hands perfusion and induced a significant decreasing of plasma AM concentrations. Side effects were negligible, easy to control and reversible. Reduction of frequency and severity of RP attacks was recorded. In conclusion, NAC seems to act as an effective vasodilatator in the treatment of RP secondary to SSc and, in addition, it induced significant changes in plasma levels of AM, a potent vasodilator endothelial-derived peptide.

Regional diastolic function by tissue Doppler echocardiography in systemic sclerosis: correlation with clinical variables

The incidence of left ventricular (LV) diastolic dysfunction is increased in systemic sclerosis (SSc), while systolic dysfunction is present in a small percentage of patients. The aim of this study was to asses the LV “regional” diastolic abnormalities in SSc patients by the mean of Doppler tissue imaging (DTI). Echocardiographic echo-Doppler (DE) and DTI parameters were analyzed for 67 SSc patients: abnormal E/A ratio at DE was detected in 24, while abnormal e/a at DTI was observed in 41. A significant prevalence of DTI diastolic abnormalities in the segments reflecting longitudinal versus those reflecting radial LV motion was found. The segments of the basal regions of LV myocardium were significantly more involved than those of the middle portion. Linear correlation was observed between the extent of the diastolic abnormalities and the duration of disease. Longitudinal myocardial systolic velocities were significantly reduced in patients with abnormal e/a DTI.

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.

Study of Raynaud's phenomenon by means of infrared functional imaging

Infrared functional imaging was applied to the study of Raynauds Phenomenon obtaining a simultaneous assessment of the thermal properties of all five fingers of both hands of a group of patients with respect of a control group. The method is based on the use of high-resolution telethermography imaging and allows identification of objective parameters from the re-warming curves of finger immediately after a 2 min cold stress. The evaluation of the area under the temperature versus time curve, namely the temperature integral INT, provides a figure particularly effective in describing the thermal properties of the finger. 18 healthy volunteers, 20 Secondary Scleroderma and 20 Primary Raynauds Phenomenon patients were studied subsequently to clinical evaluation and nailfold capillaroscopy. This new approach highlighted a quite different behaviour between patients with Primary Raynauds Phenomenon and those with early diagnosed Systemic Sclerosis This new method, compared with other existing techniques, seems to be useful tool to discriminate between PRP and RP secondary to SSc.