A scanning laser-Doppler velocimeter, able to measure blood flux over a large area without contact with the skin surface, was used for the objective measurement of the vascular changes in psoriasis. Individual plaques were scanned, and tracings of the visible plaque edge taken on to a cellulose-acetate sheet from which area measurements were made using a digitizing tablet. Mean blood flux within plaques was increased fourfold compared with mean background flux. There was a highly significant linear correlation between plaque area measured by tracing and scanning, but area measured by scanning was greater. Detailed study of blood flux outside the visible plaque edge with the scanner, and with a conventional laser-Doppler instrument, showed this was due to a 2-4 mm rim of increased blood flux around plaques. The scanning laser-Doppler velocimeter allows rapid measurement of psoriasis in terms of mean blood flux and area of increased blood flux, and should be useful in the assessment of psoriasis severity and the response to treatment.

Combining PUVA with other therapeutic agents which reduce the UVA dose required for clearance of psoriasis may be of benefit by reducing the long-term risk of cutaneous malignancy and by increasing the efficacy of treatment. We have therefore studied the effect of calcipotriol in 13 patients with plaque-type psoriasis who were about to start twice weekly PUVA. In each patient, from the start of PUVA treatment, two plaques on symmetrical body sites were selected for assessment. Calcipotriol ointment was applied to one twice daily, and placebo to the other. Response was assessed weekly for 6 weeks: an investigator, unaware of treatment allocation, compared psoriasis severity within each of the plaques, and blood flux was measured using a scanning laser-Doppler velocimeter. Of the 11 patients who completed the study, in nine the calcipotriol-treated plaque either cleared before the placebo-treated plaque (n = 7), or was consistently judged to be better (n = 2). From the third week of the trial, mean blood flux was significantly lower in the calcipotriol-treated plaques than in those treated with placebo. In the seven patients whose psoriasis was clear in at least one plaque at the end of the study period, there was a median reduction in UVA dose of 26.5% for calcipotriol compared with placebo. With the exception of one patient, the improved response was not associated with earlier relapse.

In this study we examined the prevalence of mercury hypersensitivity in patients with oral lichenoid reactions (OLR) and the effect of amalgam replacement in subjects with amalgams adjacent to OLR irrespective of their mercury sensitivity status. One hundred and ninety-seven patients with oral problems were examined: 109 with OLR, 22 with oral and generalized lichen planus, and 66 with other oral diagnoses, including aphthous ulcers and orofacial granulomatosis. Nineteen per cent of patients with OLR reacted to mercury on patch testing, significantly more than in those with generalized lichen planus (0%) and in those with other oral diagnoses (3%). Twenty-two patients with OLR and adjacent amalgams had amalgam replacement and, in 16 of 17 mercury-positive subjects and three of four mercury-negative subjects, the OLR resolved after amalgam removal. In conclusion, we found a significantly increased prevalence of mercury hypersensitivity in patients with localized OLR in comparison to subjects with other oral problems. Amalgam replacement resulted in resolution of OLR in the majority of patients with amalgams adjacent to OLR irrespective of their mercury sensitivity status.

In this study we examined the prevalence of mercury hypersensitivity in patients with oral lichenoid reactions (OLR) and the effect of amalgam replacement in subjects with amalgams adjacent to OLR irrespective of their mercury sensitivity status. One hundred and ninety-seven patients with oral problems were examined: 109 with OLR, 22 with oral and generalized lichen planus, and 66 with other oral diagnoses, including aphthous ulcers and orofacial granulomatosis. Nineteen per cent of patients with OLR reacted to mercury on patch testing, significantly more than in those with generalized lichen planus (0%) and in those with other oral diagnoses (3%). Twenty-two patients with OLR and adjacent amalgams had amalgam replacement and, in 16 of 17 mercury-positive subjects and three of four mercury-negative subjects, the OLR resolved after amalgam removal. In conclusion, we found a significantly increased prevalence of mercury hypersensitivity in patients with localized OLR in comparison to subjects with other oral problems. Amalgam replacement resulted in resolution of OLR in the majority of patients with amalgams adjacent to OLR irrespective of their mercury sensitivity status.

Disease severity on admission for patients with psoriasis is greater in tertiary referral centres for psoriasis and is directly associated with length of stay. Length of stay should be used in conjunction with clinical measures such as PASI improvement to set national standards for quality in secondary care.