Wolf-Dieter Schmidt

Biosurgery supports granulation and debridement in chronic wounds: clinical data and remittance spectroscopy measurement

Background Maggot therapy (biosurgery) has received increasing interest for the debridement of chronic wounds and for the improvement of wound healing. The purpose of this study was to investigate the clinical effects, side‐effects, and possible mechanisms of action of biosurgery.

Some effects of a topical collagen-based matrix on the microcirculation and wound healing in patients with chronic venous leg ulcers: preliminary observations.

Themicrocirculation of the wound bed is a key parameter for improving granulation tissue formation and, hence, wound healing. The aim of this study was to determine whether a wound dressing comprising collagen/oxidized regenerated cellulose has effects over a short term on wound healing. Wounds were evaluated using a clinical wound score; pain associated with wounds was measured using a visual analogue scale. Wound microcirculation was evaluated using a technique based on noncontact remission spectroscopy. A prospective trial was performed in 40 patients with chronic venous leg ulcers (mean age 74 years; range, 43-93 years; 25 females and 15 males). Patients in group A were treated with PROMOGRAN® Matrix (Johnson& Johnson, New Brunswick, NJ) combined with “good” ulcer care for 2 weeks. Control group B consisted of 10 patientswho received only good ulcer care. The authors measured a favorable clinical response in 76.9% (group A) versus 66.7% (group B). Themean reduction of ulcer area was statistically significant in group A (P < .05). The wound score improved in group A from 2.28 ± 1.24 (before treatment) increasing to 3.72 ± 1.57 (after 1 week; P < .00023) and 4.92 ± 1.68 (after 2 weeks; P < .000027). In group B, the score improved from 1.44 ± 1.33 (before treatment) to 3.22 ± 1.30 (after 1 week; P < .0077). The mean visual analogue pain score before treatment was 8.72 (group A) and 7.88 (group B) (ns,P > .05). After 1 week of treatment, the score dropped to 5.76 (group A) and 6.66 (group B). In the second week, group A patients had a mean pain score of 3.84 compared with the pain score before treatment (P < .05). After 1 week of treatment, in group A there was a decrease in remission spectroscopy, which is considered to reflect an improvement in microcirculation.

In vivo spectroscopy in dermatology: methods and new fields of application

Background The human skin is an easily accessible organ on which non‐invasive examination methods can be applied. Remittance spectroscopy uses registration of the proportion of reflected light from the skin surface. Optical characteristics of skin are determined by scattering, reflection and absorption. The remittance is influenced by various test conditions and topography. Spectroscopic methods are applied for determination of microcirculation, measuring of erythema and pigmentation and in pharmacology and toxicology of applied drugs.

Effects of low-frequency ultrasound on microcirculation in venous leg ulcers.

Background: Therapeutic low-frequency ultrasound (US) has been used for many years to improve wound healing in chronic wounds like venous leg ulcers. No human data are available for the possible effects of single US applications on microcirculation and their frequency-dependency. Aims: To investigated the role of therapeutic low-frequency US on microcirculation of venous leg ulcers in vivo. Patients and Methods: This is a pilot study on an inpatient basis. We use a newly developed low-frequency continuous-wave US-equipment composed of a US transducer based on piezo-fiber composites that allow the change of frequency. In this study, we apply US of 34 kHz, 53.5 kHz, and 75 kHz respectively. Twelve patients with chronic venous leg ulcers are analyzed. As an adjunct to good ulcer care, therapeutic US is applied, non-contacting, once a day, in a subaqual position for 10 minutes. Microcirculation is assessed in the ulcers adjacent to skin before US-therapy, immediately after the treatment and 30 minutes later. We use a micro-light guide spectrophotometer (O2C, LEA Medizintechnik GmbH, Gieίen, Germany) for calculation of blood flow velocity, hemoglobin oxygen saturation (SCO2) and relative hemoglobin concentration (rHb) in 2 and 8 mm depth. Contact-free remission spectroscopy (SkinREM3, Color Control Chemnitz GmbH, Chemnitz, Germany) allows contact free measurements in the VIS-NIR range of the spectrum (400 ± 1600 nm). Results: It is seen that therapeutic US is well tolerated. One patient dropped out from a treatment series since he developed erysipelas responding to standard antibiotic. Effects were seen at 34 kHz only. The SO2 values increased after single US application. The values for rHb were higher in the superficial layer of the wound bed (depth 2 mm) compared to deeper parts (8 mm depth). US treatment did not result in significant changes of rHb and blood cell velocity. The data obtained by remission spectroscopy disclose an increase of oxygenized hemoglobin. Conclusions: The major findings are that continuous-wave low-frequency US of 34 kHz, but not, 53.5 kHz or 75 kHz, has a temporary stimulatory effect on microcirculation mainly due to an improved oxygenation. Further studies with treatment series are necessary.

Fluorescence–remission sensoring of skin tumours: preliminary results

Objective: Nonmelanoma skin cancer (NMSC) is one of the most common malignancies in men. Objective evaluation by digital dermoscopy, as for pigmented lesions, does not provide sufficient data to discriminate between benign and malignant lesions. Therefore, other techniques have to be developed.

Two-laser, large-field hyperspectral microarray scanner for the analysis of multicolor microarrays.

We describe the development and operation of a two-laser, large-field hyperspectral scanner for analysis of multicolor genotyping microarrays. In contrast to confocal microarray scanners, in which wavelength selectivity is obtained by positioning band-pass filters in front of a photomultiplier detector, hyperspectral microarray scanners collect the complete visible emission spectrum from the labeled microarrays. Hyperspectral scanning permits discrimination of multiple spectrally overlapping fluorescent labels with minimal use of optical filters, thus offering important advantages over standard filter-based multicolor microarray scanners. The scanner uses two-sided oblique line illumination of microarrays. Two lasers are used for the excitation of dyes in the visible and near-infrared spectral regions. The hyperspectral scanner was evaluated with commercially available two-color calibration slides and with in-house-printed four-color microarrays containing dyes with spectral properties similar to their commercial genotyping array counterparts.

Noncontacting diffuse VIS-NIR spectroscopy of human skin for evaluation of skin type and time-dependent microcirculation

Spectroscopic investigations of the VIS-NIR range allow the objective determination of pigmentation, blood microcirculation and water content of human skin. Non- contacting in vivo measurements of the human skin of 50 volunteers reflect the clinical skin type well. Our correlation analysis yields that the red/infrared spectral range can be used for a determination of skin type. The observed strong spectral variations within the same group of skin type are likely based on the high biological variability of human skin and subjective clinically observed skin type. Therefore it can be useful to measure the full spectral range and to calculate a non-observed skin score with multivariate spectral methods. By multivariate analysis a correct classification of remittance spectra can be obtained. Time- depending spectral variations of dermal microcirculation can be measured at defined locations of the body, for instance the dynamics of oxygenation or blood volume in the skin of the fingertip. The cardial, pulmonal and vasomotoric waves of the micro- and macrocirculation are clearly visible at different wavelengths. The spectroscopic informations are important as an objective measure for the skin type evaluation, the penetration behavior of pharmaca, laser surgery, and therapy.

Targeted 307 nm UVB-phototherapy in psoriasis. A pilot study comparing a 307 nm excimer light with topical dithranol

Phototherapy is a cornerstone in treatment of moderate‐to‐severe psoriasis. Narrow‐band UVB has been shown to be a potent therapeutic tool. To reduce the potential carcinogenic risk, targeted phototherapy has been developed using excimer lasers or excimer light devices (ELD).

Fluorescence remission spectroscopy of psoriatic lesions and the effect of topical anthralin therapy.

Background  Psoriatic lesions are characterized by induration, scaling and erythema. Erythema is a result of inflammation and increased microvascular blood flow. Anthralin is the strongest topical antipsoriatic drug that causes clearing of psoriatic lesions and temporary remission.

Vis-NIR spectroscopic and clinical evaluations of the response of spider leg veins to a high-powered, pulsed diode laser (810 nm) therapy

Spider leg veins represent an important aesthetic problem. This clinical study was performed to investigate the pulsed near-infrared diode laser (810 nm) treatment of spider leg veins. 35 female patients were enrolled in this study and treated twice with laser densities of energy (fluence) between 60 - 100 J/cm2 and a spot size of 50 mm2. Histological examinations were performed to investigate morphological and functional effects. Spectroscopic investigations were used as a non-invasive evaluation tool. After the first laser treatment 15 patients showed a complete disappearance (CR); in the remaining 20 patients a remarkable improvement (RI) was seen (N=35). After six months of follow-up CR was noted in 6 patients, RI in 6, a stable situation in 9, and scar formation in one patient (N=21). The histological examination before and after laser treatment showed no cellular inflammatory reactions. The mean vascular areas were significantly reduced after the laser treatments. Vis-NIR spectroscopic investigations showed almost an immediate occurrence of the haemoglobin double peak and a prompt decrease of the visible remittance after laser treatment of the skin. Pulsed diode laser therapy is a safe and effective option for the treatment of spider leg veins. Objective in vivo- monitoring by remission spectroscopy and the histology of biopsy specimens show the immediate and long-term laser effects of the irradiated skin in detail.