The role of phototherapy in the surgical treatment of vitiligo: a systematic review

Vitiligo is frequently treated with the combination of phototherapy and melanocyte transplantation. However, the additional benefit of phototherapy is unclear. Moreover, the optimal type and regimen of phototherapy are unknown. The objective of this systematic review was to identify whether phototherapy improves the outcome of melanocyte transplantation in vitiligo. We searched and screened for eligible studies in the databases of MEDLINE, EMBASE and CENTRAL. We included all clinical studies investigating melanocyte transplantation combined with phototherapy. After screening and selection of abstracts and full-texts, we found 39 eligible clinical studies with 1624 patients. The eligible studies investigated several phototherapy modalities, such as NBUVB (n = 9), PUVA (n = 19), UVA (n = 1), MEL (n = 4) and active sunlight exposure (n = 9). Four studies directly compared phototherapy versus no phototherapy and two studies confirmed the benefit of phototherapy for melanocyte transplantation. We found no significant differences in repigmentation in studies directly comparing phototherapy modalities. The overall quality of the studies was moderate to poor and high heterogeneity between studies was found. We found limited evidence that phototherapy improves the outcome of melanocyte transplantation in vitiligo. There is insufficient evidence to recommend a specific type or regimen of phototherapy. More studies should be performed investigating the additional benefit of different phototherapies and the preferred moment of phototherapy

Twenty-year follow-up using a postal survey of childhood vitiligo treated with narrowband ultraviolet B phototherapy

Vitiligo is a depigmenting skin disorder with an estimated prevalence of 1%.(1) Childhood-onset vitiligo occurs in approximately a third of all cases.(2) Early-onset childhood vitiligo tends to be a more extensive and progressive type of vitiligo.(3) Narrowband ultraviolet-B (NB-UVB) phototherapy is an effective treatment option in active vitiligo and leads to >75% repigmentation in 14-75% of childhood cases.(4,5) Unfortunately, no evidence is available whether this repigmentation is long-lasting. To date, no data are available on the long-term efficacy and safety of NB-UVB in childhood vitiligo. This article is protected by copyright. All rights reserve

Focal vitiligo: long-term follow-up of 52 cases

Focal vitiligo is characterized by depigmented patches located in a small area without a typical segmental distribution. Focal vitiligo is classified as an undetermined type of vitiligo, and a more definitive diagnosis can be made when the lesions have not evolved into non-segmental or segmental vitiligo after a period of 1-2 years. However, the chance of progression is not known and may lead to treatment-indecision. The objective was to study the characteristics of patients with focal vitiligo and possible predictors of progression. We conducted a survey study in patients with initial diagnosis of focal vitiligo between January 2005 and June 2010. Focal vitiligo was defined as either a small acquired isolated depigmented lesion without typical segmental distribution, or two to three small acquired lesions localized in a non-segmental area with a maximum of 5 cm. The survey comprised of 21 questions concerning the patient's characteristics, the onset of focal vitiligo, progression of depigmentation and treatment history. We identified 128 eligible patients and the response rate was 40.6% (n = 52 completed questionnaires). Progression to non-segmental vitiligo occurred in 23%. The median follow-up duration was 7 years. In 11.5% of the patients, progression to non-segmental vitiligo occurred within 2 years after onset. Nevertheless, even after a first stable period of more than 2 years, another 11.5% of the patients advanced to non-segmental vitiligo. No associated prognostic factors at baseline of progression to non-segmental or long-lasting focal vitiligo were found. Focal vitiligo is a rare subtype of vitiligo and most patients have long-lasting focal lesions after onset of the disease. In this study, focal vitiligo progressed to typical non-segmental vitiligo, but not towards typical segmental vitiligo. Progression 2 years after onset of focal vitiligo, occurs in 50% of the patients with eventual progression to non-segmental vitiligo. There seem to be no clinical signs that predict progression in focal vitilig

Autologous cell suspension grafting in segmental vitiligo and piebaldism: a randomized controlled trial comparing full surface and fractional CO2 laser recipient-site preparations

Background: Autologous noncultured cell suspension transplantation is an effective treatment for repigmentation in segmental vitiligo and piebaldism. Full surface laser ablation is frequently used to prepare the recipient site before cell suspension transplantation, even though the optimal laser settings and ablation depth are unknown. Objectives: To assess the efficacy and safety of less invasive recipient-site preparations. Methods: In a randomized, observer-blinded, controlled trial we compared different recipient-site preparations before cell suspension transplantation in segmental vitiligo and piebaldism. In each patient, we randomly allocated three CO2 laser recipient-site preparations (209 and 144 μm full surface, and fractional) and a control (no treatment) to four depigmentations. After 6 months we assessed repigmentation and side-effects. Results: We included 10 patients with vitiligo (n = 3) and piebaldism (n = 7). Compared with the control site, we found more repigmentation after full surface ablation at 209 μm (median 68·7%, P = 0·01) and 144 μm (median 58·3%, P = 0·007), but no repigmentation after fractional ablation (median 0·0%, P = 0·14). Conclusions: Superficial full surface ablation with a depth of 144 μm is an effective recipient-site preparation before cell suspension transplantation, while fractional CO2 laser is not

Development and Validation of the Vitiligo Extent Score (VES): an International Collaborative Initiative: Journal of Investigative Dermatology

The clinical assessment of vitiligo involves an estimation of the affected body surface area. The most commonly used method is the "palm of hand 1% rule" as integrated in the Vitiligo Area Scoring Index. However, this method can be challenging and time consuming. In this study, we introduce a global Vitiligo Extent Score (VES). In the first part of the study, this measurement instrument was developed and subsequently optimized during a pilot scoring session. In a subsequent stage, the inter-and intrarater reliability of the instrument were tested. Live scoring showed an excellent interrater reliability for the VES (intraclass correlation VES: 0.924 vs. Vitiligo Area Scoring Index: 0.846). Subsequent scoring on pictures was comparable with the live evaluation and demonstrated an excellent intrarater reliability. A high intraclass correlation for the VES (intraclass correlation VES: 0.923 vs. Vitiligo Area Scoring Index: 0.757) was also found in an additional subgroup of patients with extensive vitiligo. Moreover, user-friendliness and timing were scored very favorably. In conclusion, this measurement instrument allows us to monitor accurately and easily the affected body surface area in a standardized way. Moreover, our results provide evidence that the VES can be proposed as a promising tool to measure the vitiligo extent in clinical trials and in daily practice

The role of rejuvenators in embedded damage healing for asphalt pavement

Rejuvenator encapsulation technique showed great potential for extrinsic asphalt pavement damage healing. Once the capsules are embedded within asphalt pavement, the healing is activated on-demand via progressing microcrack. When the microcrack encounters the capsule, the fracture energy at the tip opens the capsule and releases the rejuvenator. Then the released rejuvenator wets the crack surfaces, diffuses into and softens the aged bitumen, allowing two broken edges to come in the contact, preventing further asphalt pavement deterioration. The quality and speed of the damage repair process strongly depend on the quality of rejuvenator, thus it is important to choose a proper rejuvenator with good abilities to restore the lost properties of bitumen from ageing and show a sustainable performance after healing. To this aim, three different rejuvenators were studied and ranked based on the performance of their rejuvenated bitumen, including physical properties, rheological properties, chemical properties and the performance after re-ageing. Furthermore, these rejuvenators were encapsulated in calcium alginate capsules and the tests on these capsules indicate the diameter, mechanical resistance and thermal stability of the capsules are influenced by the encapsulated rejuvenator. The findings will benefit the development of rejuvenator encapsulation technique and the optimization of the capsule healing system towards a better healing effect in asphalt pavement.Materials and EnvironmentPavement Engineerin

Biopolymer scleroglucan as an emulsion stabilizer

In this study, we investigated the Stabilization of bitumen emulsions by scleroglucan, a rigid triple-helix forming biopolymer, in combination with a pH-sensitive cationic surfactant. Various aspects of the emulsification process and the final composition influence the Stabilization. We examined two different methods to add scleroglucan to the emulsion: either by adding it to the aqueous surfactant solution before emulsification, denoted ‘pre-emulsification addition’ (pre-EA), or by addition to the emulsion after emulsification (post-EA). We investigated scleroglucan concentrations in the aqueous phase ranging between 0.017 and 0.07 w/w%. The emulsions were evaluated according to the European EN 13808 standard used for cationic bituminous emulsions, as well as by rheological analysis. We observed an improvement of the storage stability upon pre-EA at a biopolymer concentration as low as 0.017 w/w% in combination with an increased particle size, whereas the breaking index (characterising breaking of the emulsion in presence of ‘aggregates’ = stones) was not influenced. The rheological data show a minor viscosity increase by scleroglucan in the pre-EA formulation at low scleroglucan concentrations (0.017–0.05 wt.%) where Stabilization already improved dramatically. This indicates that the stabilization mechanism is not only governed by a viscosity increase but also by interfacial stabilisation effects were polymer is adsorbed onto the adsorbed surfactant. In a separate experiment we changed the conformation of scleroglucan by subjecting it to extreme pH values and by dissolution in DMSO, in order to study the role of the triple helix conformation in the stabilization mechanism. Scleroglucan becomes less effective in a denatured and hydrolysed state confirming the crucial role of the triple helix conformation in the Stabilization of bitumen emulsions.ChemE/Advanced Soft MatterOLD ChemE/Organic Materials and Interface