silicon and Erythema

Chronic wounds require frequent dressing changes. Adhesive dressings used for this indication can be damaging to the stratum corneum, particularly in the elderly where the skin tends to be thinner. Understanding the level of damage caused by dressing removal can aid dressing selection.. This study used a novel methodology that applied a stain to the skin and measured the intensity of that stain after repeated application and removal of a series of different adhesive types. Additionally, a traditional method of measuring skin barrier damage (transepidermal water loss) was also undertaken and compared with the staining methodology.. The staining methodology and measurement of transepidermal water loss differentiated the adhesive dressings, showing that silicone adhesives caused least trauma to the skin.. The staining methodology was shown to be as effective as transepidermal water loss in detecting damage to the stratum corneum and was shown to detect disruption of the barrier earlier than the traditional technique.

Topics: Adult; Aged; Bandages; Blister; Body Water; Colorimetry; Edema; Epidermis; Erythema; Female; Humans; Male; Middle Aged; Silicon; Skin Diseases; Staining and Labeling; Surgical Tape; Water Loss, Insensible

To determine the impact of skin pretreatment with microneedles (MNs) on ALA- and MAL-induced protoporphyrin IX (PpIX) production, as well as MN impact on pain sensations during light exposure and erythema after PDT.. The skin of 14 healthy volunteers was preteated with MNs. Equal amounts of creams containing 2%, 8% and 16% (w/w) ALA and MAL were applied on 1 cm(2) areas for 4 h. Additionally, 16% ALA and MAL creams were applied for 24 h. Afterwards, PpIX fluorescence spectra were measured. Sixteen percent ALA and MAL spots were exposed to red light (632 nm, 77 mW/cm(2)). Time for pain to occur was measured in seconds, and erythemal response was monitored up to 6 h after the end of the light exposure.. Use of MNs increased the PpIX fluorescence after 4 h incubation time with 2% and 8% ALA or MAL, but not with 16% ALA or MAL. Pretreatment with MNs did not increase the pain sensations during light exposure, nor did it influence erythema occurrence.. MNs are a promising tool for improving the efficiency of topical PDT by improving the cutaneous delivery of ALA and MAL, without increase in side effects.

Topics: Administration, Cutaneous; Adult; Aminolevulinic Acid; Erythema; Female; Humans; Light; Male; Needles; Pain; Photochemotherapy; Photosensitizing Agents; Protoporphyrins; Punctures; Silicon; Skin; Skin Absorption