Biomechanical properties of infantile hemangiomas: clinical stage and effect of age

Clinical Outcomes of Small Infantile Hemangiomas Treated With Pulsed Dye Laser

BACKGROUND

Infantile hemangioma (IH) often causes cosmetic disfigurement. Early intervention with propranolol for large, high-risk lesions is recommended in the American Academy of Pediatrics' Clinical Practice Guideline. Conversely, strategies for the management of small, low-risk lesions have not been established; however, pulsed dye laser (PDL) is often used to treat these lesions.

OBJECTIVE

To investigate clinical outcomes of PDL in small IH lesions.

PATIENTS AND METHODS

Fifty-three cases with 58 small IHs which did not meet the criteria for high-risk lesions in the guideline and were treated only with PDL were retrospectively reviewed. The characteristics of IHs and residual skin changes after treatment were evaluated.

RESULTS

Forty-seven lesions (81.0%) were superficial hemangiomas, whereas 11 (19.0%) were combined-type. The median maximum diameter was 10.0 mm. Forty-five lesions (77.6%) exhibited various residual skin changes after PDL treatment, including anetoderma (53.5%), telangiectasia and erythema (43.1%), hyperpigmentation (34.5%), redundant skin (3.4%), and fibrofatty tissue (3.4%). Of these, the incidence of anetoderma and fibrofatty tissue were significantly higher in the combined group than in the superficial group (p = .036 and .033, respectively).

CONCLUSION

Even small lesions, especially combined-type, often result in cosmetic problems after PDL treatment.

Elasticity-dependent response of malignant cells to viscous dissipation

The stiffness of the cellular environment controls malignant cell phenotype and proliferation. However, the effect of viscous dissipation on these parameters has not yet been investigated, in part due to the lack of in vitro cell substrates reproducing the mechanical properties of normal tissues and tumors. In this article, we use a newly reported viscoelastic polyacrylamide gel cell substrate, and we characterize the impact of viscous dissipation on three malignant cell lines: DU145 and PC3 derived from prostate and LN229 from brain. The spreading, motility and proliferation rates of these cells were analyzed on 1 kPa and 5 kPa elastic and viscoelastic gels. Surprisingly, the effect of substrate viscous dissipation on cell behavior depended on substrate stiffness for the three cell types tested. We conclude that viscoelasticity controls the spreading, proliferation and migration of malignant cells in vitro. These results highlight the critical role of viscous dissipation in the phenotype and proliferation of malignant cells, especially in stiff tumor environments.

Liposuction for large facial involuted infantile hemangiomas in children: clinical evaluation and management strategies

BACKGROUND

Large involuted infantile hemangioma (IH) can cause facial disfigurement and functional impairment and constitute a major concern to children and parents. Liposuction for large involuted IH has been reported in some case reports. However, systematic study is seldom and the patient outcome is uneven.

METHODS

Thirteen eligible patients who underwent liposuction treatment at Shanghai Ninth People's Hospital between August 2016 and August 2018 were reviewed. IH lesions were evaluated according to their timing, components, involvement, and location. Liposuction was performed to address the volumetric residue.

RESULTS

Between August 2016 and August 2018, 13 patients, four boys and nine girls, with an average age of 8 ± 4.4 years underwent the liposuction for large facial involuted IH. Clinical follow-up ranges from 3 to 18 months. In two cases, lipectomy and facelift were undertaken in conjunction with liposuction. One patient needs a secondary revision due to the residual facial asymmetry. All patients were satisfied with the outcomes.

CONCLUSIONS

Liposuction for large involuted IH is reliable and underreported in the literature. With proper patient evaluation and good counseling on realistic expectations, liposuction for large facial involuted IH can be expected to achieve excellent results with a low complication rate in pediatric population.

Infant skin maturation: Preliminary outcomes for color and biomechanical properties

BACKGROUND

Newborn infant skin changes after birth but studies have focused on the epidermal barrier. Dermal properties are relevant for care, but literature on postnatal changes is sparse. We further characterized skin maturational changes in lightness, color and response to biomechanical stress.

METHODS

Normal skin sites from subsets of participants in a trial on the progression and stage of infantile hemangiomas were retrospectively examined. Standardized photographs were analyzed as L*, a*, and b* images. Biomechanics were measured with the Cutometer^® .

RESULTS

Color changed significantly with increasing age. Skin was darker and redder at 2.0 vs. 5.4, 8.5 and 12.8 months. Yellow color increased, with higher values at 12.8 vs. 2.0, 3.5 and 5.4 months. Chest tissue was consistently more elastic than arm and face sites, with significantly higher elasticity for the youngest and oldest age groups. Biological elasticity, elastic recovery, and total recovery were significantly greater for the oldest subjects. Viscoelasticity and elastic deformation were lower at 5.5 vs. 8.8 and 17.6 months. Arm viscoelastic creep was highest at 2.8 months.

CONCLUSION

Skin maturation continues into year two. Increasing elasticity and decreasing viscoelasticity may reflect increased collagen structure/function. The findings have implications for prevention of skin injury associated with mechanical forces.