How biophysical in vivo testing techniques can be used to characterize full thickness skin equivalents.

BACKGROUND: The reliability of the biophysical properties of skin equivalents (SEs) remains a challenge for medical applications and for product efficacy tests following the European Directive 2003/15/EC2 on the prohibition of animal experiments for cosmetic products. METHODS: We propose to adapt the biophysical in vivo testing techniques to compare full thickness model growth vs. time. The interest in using such techniques lies in possible comparisons between in vivo and in vitro skin as well as monitoring samples over the culture time. RESULTS: High frequency ultrasound technique, optical coherence tomography (OCT), and laser scanning microscopy were used to analyze SEs morphology at days D42 and D60 whereas their microstructure was assessed through transmission electron microscopy and classical histology. A correlation between these observations and mechanical measurements has been proposed so as to underline the consequence of both the development of the dermis elastic fibers and the epidermis differentiation. CONCLUSION: Ultrasounds measurements show a highly homogeneous dermis whereas the OCT technique clearly distinguishes the stratum corneum and the living epidermis. The increase in the thicknesses of these layers as well as the growth in elastin and collagen fibers results in strong modifications of the samples mechanical properties.

[Management of ocular and orbital complications in acute sinusitis]. / Prise en charge des complications oculo-orbitaires des sinusites aiguës.

PURPOSE: Describe the clinical presentations of orbital complications of acute sinusitis and discuss therapeutic approaches. METHODS: Retrospective study of 29 cases of acute sinusitis with orbital extension hospitalized over a period of 12years (2000 to 2012). RESULTS: There were 23 men and 6 women. The mean age was 15.75years. The average time until consultation was 7.68 days. Sinusitis was ethmoido-maxillary in 20 cases, ethmoidal in 6 cases, and frontal in 3 cases. Orbital extension was grouped according to the Chandler classification: stage I (3 cases), stage II (3 cases), stage III (15 cases), stage IV (8 cases). Antibiotic therapy was prescribed in all cases. Surgery was performed in 22 cases. Bacterial cultures revealed streptococcus (2 cases), aspergillus fumigatus (1 case) and were negative in 8 cases. The outcome was favorable in 27 cases. In two cases, the outcome was unfavorable with associated intracranial complications. DISCUSSION: Oculoorbital extension of acute sinusitis is a diagnostic and therapeutic emergency. Paranasal sinus CT is essential to confirm orbital extension and identify the causative sinus. Intravenous antibiotic therapy is the main treatment. The roles of corticosteroid and heparin therapy remain controversial. Surgery is indicated in the case of abscess or high visual risk. Endoscopic endonasal surgery appears to have a double role, in diagnosis and treatment.