Publications

The study reviewed minimal erythema dose (MED) test results from over 1,000 patients across phototherapy centres in Dundee and London to better understand how skin types respond to narrowband UVB light before treatment.  MED values generally increased with darker Fitzpatrick skin phototypes, but there was substantial overlap between groups and between centres, with Dundee showing slightly lower MEDs than London.  Non response to testing was very rare among lighter skin types (I-III) but more common in darker skin types (IV-VI), suggesting that broader or higher test dose ranges may be needed for these patients.  Overall, the findings support the current testing approach for lighter skin types and highlight the need for adjusted protocols to ensure accurate, inclusive, and safe phototherapy dosing across all skin types.

Publication: Narrowband ultraviolet B minimal erythema dose reference range  

Broad-spectrum abnormal localized photosensitivity syndrome (BALPS) is a rare condition in which sunlight triggers recurrent, itchy red rashes at the same specific skin sites.  This case report describes a man with a 10-year history of sun-induced eruptions confined to the waistline and underarm areas.  Specialized phototesting showed abnormal sensitivity to both UV-A and UV-B light only in the affected skin, while unaffected areas responded normally.  These findings helped confirm the diagnosis and distinguish BALPS from more widespread photodermatoses.  Management focuses on strict photoprotection of the affected areas and topical corticosteroids during flare-ups.  Increased awareness of BALPS is important to support accurate diagnosis and improve patient outcomes.

Publication: Broad-Spectrum Abnormal Localized Photosensitivity Syndrome

Photodiagnostic testing is a vital tool for diagnosing conditions where the skin is abnormally sensitive to light. Historically, comparing how much ultraviolet (UV) radiation triggers a reaction has been difficult because different light sources and wavelengths produce widely different results when measured in traditional units (mJcm−2). To solve this, we can use the Standard Erythema Dose (SED), a measurement designed to be independent of the specific light source used. Using SED significantly reduces the variation between different wavelengths, allowing doctors to more consistently compare phototesting results with established "normal" ranges regardless of the equipment or the specific centre performing the test. This standardisation leads to more reliable and accurate diagnoses for patients with photosensitivity.

Publication: Quantity of ultraviolet radiation required to produce erythema: normal ranges in phototesting