Imaging techniques have only recently been utilized in combination with clinical observation to objectively quantify psoriasis severity and evaluate therapeutic response. This study evaluated the sensitivity of videodermatoscopy (VO) and ultrasound (US) imaging to assess the therapeutic effect of cyclosporine (Cs) in patients with moderate-to-severe psoriasis. Twenty patients with moderate-tosevere psoriasis were divided into two groups (A and B) based on PASI score. Group A (PASI >16) was treated with 5 mg/Kg/day Cs for 4 weeks and another 4 weeks with 3 mg/Kg/day Cs. Group B (PASI 10-16) received 3 mg/Kg/day Cs for 8 weeks. A "target" plaque was selected for each subject and evaluated using a Target Lesion Score (TLS) for erythema, scaling and degree of infiltration, in addition to VO and US at baseline, 2, 4 and 8 weeks. At the end of the study, improvement rate was quicker in group A vs group B after 8 weeks of Cs therapy. All three parameters (TLS, VO and US) strongly correlated with one another. Skin thickness was the first parameter that improved, followed by TLS. In contrast, improvement in VO was delayed. Normalization rate of vascular pattern (assessed by VO) was low in both groups but higher in group A vs group B (46% vs 22%), despite virtually complete normalization by clinical and US assessment. In conclusion, while both TLS and US can be utilized in the evaluation of therapeutic efficacy in patients with plaque psoriasis, VO can provide information on vascular response to treatment, which may likely affect the duration of therapy and the relapse rates.