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Background:It is estimated that about 15% (10% - 30% in most of the studies) of the total adult population has some aspects of the Chronic Venous Insufficiency (CVI). Frequency of the Peripheral Arterial Disease (PAD) in the adult population is 3% - 4%. Studies dealing with etiopathogenesis of leg ulcers show that between 10% and 18% of all ulcers are of mixed, arterial-venous origin.Objectives:The purpose of this study was to find out if there is a higher frequency of PAD among CVI patients in comparison with the control group, as well as to discover some common risk factors for CVI and PAD.Patients and Methods:This cross-sectional descriptive study was conducted at the dermatovenereological clinic, clinical center of Vojvodina, Serbia. A total of 162 examinees were included. All patients were examined for the existence of CVI and staged according to CEAP (Clinical, etiology, anatomy and patophysiology) classification. In this way, 3 groups were formed: Patients with the mild forms of CVI (stage 1 - 4 by CEAP classification), 57 patients; patients with the severe forms of CVI (stage 5 and 6 by CEAP classification), 55 patients; control group (no CVI), 50 patients. Also, the Ankle Brachial Pressure Index (ABPI) was assessed in all subjects, and its value of ≤ 0.9 was set as criteria for diagnosis of PAD. The same sample was divided according to the presence of PAD into two groups. The most important risk factors for CVI and PAD were identified for each patient through complete examination, medical record and appropriate questionnaire.Results:Our results showed that the risk factors for CVI were high Body Mass Index (BMI), hypertension, predominantly standing position during work and positive family history for CVI. In the same sample it was found that 28 (17.28%) patients had PAD. Relevant risk factors for PAD in the present study were: high BMI, hypertension, diabetes and a positive family history for PAD. Comparison of frequency of PAD among patients with severe forms of CVI and control group showed that this difference was statistically significant (P = 0.0275; OR 3.375; 95% CI 1.125 - 10.12). After multivariate analyses, adjusted odds ratio OR was still statistically significant.Conclusions:The peripheral arterial disease is more frequent in patients with the severe form of CVI, than in patients without CVI. Concomitant risk factors for CVI and PAD were high BMI and hypertension. In each patient with severe CVI it is necessary to determine the ABPI, in order to exclude the presence of PAD.

Epidemiology of atopic dermatitis Atopic dermatitis (AD) is a disease that usually presents in the early childhood (1). AD is one of the most common skin diseases and it affects approximately 20% of children and 1-3% of adults (2). In 60% of patients the first manifestations appear within the first year of life, and in 90% of patients before the age of five. In most patients manifestations of AD disappear before the adulthood, while in 25% of patients AD persists throughout life (2). Rarely, the first AD manifestations appear in adulthood (2). Approximately 25% of AD patients may develop some form of hand eczema during the life (3). Clinical presentations of AD The clinical presentations of AD vary depending on the age and course of the disease; the major manifestations include erythema, edema, xerosis, erosions/excoriation, oozing and crusting, and lichenification (1, 4, 5, 6, 7). Intense itching is common in AD resulting in excoriation, pruritic papules, lichenification and eczematous skin lesions (2, 3, 4). The itch is particularly pronounced at night causing sleep impairment, thus having significant negative impact on the quality of life of both patients and their families (2, 3, 5, 6). The disease may take an acute, subacute or chronic course. Acute lesions are characterized by intense pruritus, presence of papules and vesicles on erythematous skin, and are associated with excoriation, erosion and serous exudates. Subacute lesions manifest as erythematous, excoriated scaly papules, while typical skin thickening with pronounced skin markings (lichenification) and pruritic papules are distinctive for the chronic course of the disease. In infants and young children, AD commonly starts as an acute or subacute condition, whereas chronic forms are characteristic for older children and adults (5, 6, 7). These three distinct phases are often observed in the same patient (6, 7). Clinical presentations in children During the first month of life, the first signs of atopic dermatitis may present as pronounced yellowish scales on the scalp, commonly known as "cradle cap" or infantile seborrheic dermatitis (1). In infants, 3-6 months old, the predilection sites for eczematous changes on the face are cheeks, forehead and chin, whereas the central part of the face (nose, perioral region) and diaper area are often spared. Skin changes are acute or subacute, with unclear margins, and present with erythema, edema, papulovesicles, excoriations, often associated with oozing and crusting, while chronic changes are rare and manifest as erythematous papules and plaques with desquamation. In infants 8-10 months old, AD progresses to extensor surfaces of the extremities, and after the first year it may affect the upper trunk, where the changes manifest as nummular dermatitis (1, 5, 6, 7). After the age of 2 years, the clinical presentations change, that is, the disease takes a chronic course, or AD develops de novo. The symptoms include poorly marginated lichenified plaques with excoriations

Visual perception of human skin is determined by the light that reflects off the skin surface to retina and interpretation of these information by visual centers in the brain cortex. Skin has a partly translucent and turbid structure and visual perceptions depend on interactions between the light and structures of the skin surface and below it, through absorption, reflection and scattering. Light absorption by the skin depends on the composition, absorption spectra and amount (volume fraction) of chromophores. Subsurface scattering occurs within the skin layers: Rayleigh scattering (subcellular structures sized up to 1/10 of incident wavelength) and Mie scattering (collagen, melanosomes). Due to fluctuations of the refractive index within tissue components and intense scattering, the spatial distribution of light within the skin is diffuse. Skin images are created by the light that reflects off the skin after being color-modified by absorption and being scattered on the skin surface and internal skin structures.