Figure 2. Chronic stage of the cutaneous radiation syndrome (CRS). (A) Schematic drawing of the pathophysiological processes involved. (B) Clinical aspect of the chronic stage, 6 years after exposure (lower leg of a survivor of the accident in Chernobyl (1986), documented 1992). Note the focal radiation keratosis (benign on biopsy), telengiectasias and severe fibrosis next to epidermal atrophy. (C) Histopathology of radiation fibrosis: loss of epidermal rete-ridges, flattening of the epidermis, homogeneous collagenisation and scarce perivascular lymphocytic infiltrate. Biopsy taken from the back of a Chernobyl survivor in 1993. (D) High frequency ultrasound of chronic stage (lower leg of a Chernobyl survivor, documented in 1993) prior to treatment with interferon-. An extremely increased echogenicity from the epidermal entrance echo down to the muscle fascia indicates severe radiation fibrosis.