## 3 Results  
Skin with psoriasis and skin without psoriatic changes are characterized by different reflectance values depending on the examined wavelength range. Over the course of phototherapy, there were changes in the reflectance of both psoriatic and non- psoriatic skin, as shown in the Table 2.  
The lowest values of psoriatic skin reflectance before therapy occurred at the wavelengths of 1700-2500 nm (median 0.077 mm). For skin with no psoriasis lesions, the lowest values were also observed in the range 1700-2500 nm (median 0.073 mm). The highest reflectance values before therapy of psoriatic skin occurred in the wavelength range of 590-720 nm (median 0.529 mm). In the case of skin without psoriasis lesions, the highest reflectance values were observed in the wavelength range 700-1100 nm (median 0.553 mm). Before the therapy, psoriatic skin was characterized by a higher reflectance than the skin without psoriatic changes in the wavelength ranges 335-380 nm and 1700-2500 nm. After 10 and 20 irradiations the same dependence was observed. Soriatic skin after 20 irradiations showed lower reflectance at each of the measured wavelengths than the skin without psoriatic lesions before the therapy. Skin without psoriatic after 20 irradiations showed lower reflectance at each of the measured wavelengths than before therapy (Table 2). \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline  & & \multicolumn{2}{c}{**(1) Postside Skin Before Therapy**} & \multicolumn{2}{c}{**(2) Skin without Poortic (Strong Sparsity) after 10 Implications**} & \multicolumn{2}{c}{**(4) Skin without Pooristic**} & \multicolumn{2}{c}{**(5) Postside Skin after (5) Skin without Pooristic**} & \multicolumn{2}{c}{**(6) Skin without Pooristic**} \\  & & **Before Therapy** & **before Therapy** & **after 10 Implications** & **after 10 Implications** & **after 10 Implications** & **20 Implications** & **after 20 Implications** & **after 2 \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline  & \multicolumn{3}{c}{**(O Potential Skin**} & **O2 Skin without Proximatic** & **(O) Periodic Skin** & **(O) Skin without Proximatic** & **(O) Periodic Skin after 10 Irradiations** & **(O) Periodic Skin after 20 Irradiations** & **(O) Skin without Proximatic** & **(O) Skin without Proximatic** \\  & \multicolumn{3}{c}{**Before Therapy**} & **before Therapy** & **after 10 Irradiations** & **after 10 Irradiations** & **20 Irradiations** & **after 20 Irradiations** & **after 20 Irradiations** & **\(p\)** \\ \hline  & median & 0.272 & 0.284 & 0.270 & 0.28 & 0.253 & 0.273 & 1 vs. 2 \(<\) 0.05 \\ \cline{2-9}  & Q1 & 0.258 & 0.278 & 0.258 & 0.276 & 0.242 & 0.263 & 3 vs. 4 \(<\) 0.05 \\ \cline{2-9}  & Q3 & 0.279 & 0.292 & 0.285 & 0.286 & 0.269 & 0.286 & 5 vs. 6 \(<\) 0.05 \\ \cline{2-9}  & min & 0.228 & 0.246 & 0.228 & 0.25 & 0.229 & 0.229 & 1 vs. 5 \(<\) 0.05 \\ \cline{2-9}  & max & 0.304 & 0.308 & 0.306 & 0.305 & 0.285 & 0.309 & 2 vs. 6 \(<\) 0.05 \\ \hline  & median & 0.077 & 0.073 & 0.077 & 0.07 & 0.059 & 0.058 & 1 vs. 2 \(>\) 0.05 \\ \cline{2-9}  & Q1 & 0.070 & 0.069 & 0.063 & 0.065 & 0.053 & 0.047 & 3 vs. 4 \(>\) 0.05 \\ \cline{2-9}  & Q3 & 0.077 & 0.078 & 0.088 & 0.075 & 0.005 & 0.066 & 5 vs. 6 \(>\) 0.05 \\ \cline{2-9}  & min & 0.049 & 0.059 & 0.051 & 0.059 & 0.055 & 0.019 & 1 vs. 5 \(<\) 0.05 \\ \cline{2-9}  & max & 0.126 & 0.069 & 0.123 & 0.057 & 0.003 & 0.075 & 2 vs. 6 \(<\) 0.05 \\ \hline \end{tabular}
\end{table} 
Table 2: _Cont._Differences in the thickness of the epidermis were observed between skin without psoriatic lesion and psoriatic skin. There was no statistically significant difference in the thickness of the epidermis of the non-posoriatic areas before, after 10 and after 20 sessions of phototherapy. The difference in epidermis thickness within psoriatic skin before and after the series of the 20 irradiations were statistically significant. After the end of phototherapy, the epidermis thickness decreased from median 0.289 to median 0.204 (Table 3).