## 3 Results
Higher skin density values were observed in uninvolved skin compared with psoriatic skin (Me = 32.165 vs. Me = 11.145). During phototherapy, there was an increase in skin density relative to baseline in both psoriatic and non-posoriatic skin. After 20 irradiations, there was a statistically significant increase in skin density from median 11.145 to 21.210 in the skin with psoriatic scales. Skin without psoriatic lesion also increased from median 32.165 at the baseline to 34.275 after 20 irradiations (Table 4). In the skin without psoriatic lesions, no SLEB layer was observed both before or after the series of 10 and 20 irradiations. Before the therapy, the median value of the SLEB (sub-epidermal low-echogenic band) in psoriatic skin was 0.285 mm, while after the therapy it decreased to 0.201 mm (Table 5). Phototherapy did not contribute to complete remission of psoriasis lesions. After a series of 20 irradiations, the epidermis was thinned, but the psoriatic \begin{table}
\begin{tabular}{l c c c c c c} \hline  & \multicolumn{6}{c}{**Skin Density**} \\ \cline{2-7}  & **Median** & **Q1** & **Q3** & **Min** & **Max** & \(p\) \\ \hline (1) psoriatic before therapy & 11.145 & 8.075 & 17.525 & 4.310 & 21.820 & 1 vs. 2 \(>\) 0.01 \\ (2) psoriatic after 10 irradiations & 16.025 & 12.970 & 20.225 & 6.700 & 36.230 & 1 vs. 4 \(>\) 0.01 \\ (3) psoriatic after 20 irradiations & 21.210 & 17.105 & 26.205 & 5.720 & 49.480 & 3 vs. 4 \(>\) 0.01 \\ (4) without psoriatic before therapy & 32.165 & 30.230 & 41.415 & 18.060 & 65.000 & 5 vs. 6 \(>\) 0.01 \\ (5) without psoriatic after 10 irradiations & 34.950 & 30.130 & 41.545 & 19.040 & 65.250 & 1 vs. 5 \(<\) 0.01 \\ (6) without psoriatic after 20 irradiations & 34.275 & 31.345 & 41.410 & 20.600 & 64.860 & 2 vs. 6 \(<\) 0.01 \\ \hline \end{tabular}
\end{table} 
Table 4: Density of psoriatic and non-lesional skin before, after 10 and after 20 irradiations. \begin{table}
\begin{tabular}{l c c c c c c} \hline  & \multicolumn{6}{c}{**Epidermis Thickness (mm)**} \\ \cline{2-7}
**Skin** & **Median** & **Q1** & **Q3** & **Min** & **Max** & \(p\) \\ \hline (1) psoriatic lesion before therapy & 0.289 & 0.249 & 0.336 & 0.194 & 0.381 & 1 vs. 4 \(<\) 0.01 \\ (2) psoriatic lesion after 10 irradiations & 0.250 & 0.213 & 0.296 & 0.184 & 0.398 & 2 vs. 5 \(<\) 0.01 \\ (3) psoriatic lesion after 20 irradiations & 0.204 & 0.187 & 0.257 & 0.123 & 0.298 & 3 vs. 6 \(<\) 0.01 \\ (4) without lesion before therapy & 0.130 & 0.119 & 0.150 & 0.089 & 0.232 & 1 vs. 6 \(<\) 0.01 \\ (5) without lesion after 10 irradiations & 0.133 & 0.118 & 0.148 & 0.088 & 0.250 & 1 vs. 6 \(<\) 0.01 \\ (6) without lesion after 20 irradiations & 0.130 & 0.118 & 0.151 & 0.089 & 0.231 & 4 vs. 6 \(>\) 0.01 \\ \hline \end{tabular}
\end{table} 
Table 3: Epidermis thickness of psoriatic and non-lesional skin before, after 10 and after 20 irradiations. \begin{table}
\begin{tabular}{l c c c c c c} \hline  & \multicolumn{6}{c}{**SLEB (mm)**} \\ \cline{2-7}
**Skin** & **Median** & **Q1** & **Q3** & **Min** & **Max** & \(p\) \\ \hline (1) psoriatic lesion before therapy & 0.285 & 0.205 & 0.352 & 0.112 & 0.548 & 1 vs. 2 \(<\) 0.01 \\ \hline (2) psoriatic lesion after 10 irradiations & 0.240 & 0.151 & 0.305 & 0 & 0.478 & 1 vs. 3 \(<\) 0.01 \\ \hline (3) psoriatic lesion after 20 irradiations & 0.201 & 0.080 & 0.283 & 0 & 0.980 & 2 vs. 3 \(<\) 0.01 \\ \hline \end{tabular}
\end{table} 
Table 5: SLEB layer in psoriatic skin before, after 10 and 20 phototherapy sessions. visible. The SLEB (subepidermal low-echogenic band) layer under the epidermis had also decreased (Figure 2).