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Keratoconus is an eye disorder that causes the cornea to take an abnormal conical shape, thus impairing its refractive functions and causing blindness. The late diagnosis of keratoconus is among the principal reasons for corneal surgical transplantation. This pathology is characterized by a reduced corneal stiffness in the region immediately below Bowman's membrane, probably due to a different lamellar organization, as suggested by previous studies. Here, the lamellar organization in this corneal region is characterized in three dimensions by means of second-harmonic generation (SHG) microscopy. In particular, a method based on a three-dimensional correlation analysis allows to probe the orientation of sutural lamellae close to the Bowman's membrane, finding statistical differences between healthy and keratoconic samples. This method is demonstrated also in combination with an epi-detection scheme, paving the way for a potential clinical ophthalmic application of SHG microscopy for the early diagnosis of keratoconus. SHG image acquired with sagittal optical sectioning (A) of a healthy cornea and (B) of a keratoconic cornea. Scale bars: 30 μm., (© 2016 The Authors. Journal of Biophotonics published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The healing process of superficial skin wounds treated with a blue-LED haemostatic device is studied. Four mechanical abrasions are produced on the back of 10 Sprague Dawley rats: two are treated with the blue-LED device, while the other two are left to naturally recover. Visual observations, non-linear microscopic imaging, as well as histology and immunofluorescence analyses are performed 8 days after the treatment, demonstrating no adverse reactions neither thermal damages in both abraded areas and surrounding tissue. A faster healing process and a better-recovered skin morphology are observed: the treated wounds show a reduced inflammatory response and a higher collagen content. Blue LED induced photothermal effect on superficial abrasions., (© 2016 The Authors. Journal of Biophotonics published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Illuminating films of a porous chitosan matrix containing gold nanorods and thermosensitive micelles loaded with a chemical stimulates local photothermal conversion of the gold nanorods. The heat produced activates the ejection of the chemical from the micelles (see scheme), and causes the transient permeabilization of adjacent cell membranes, resulting in a selective cellular uptake of the released chemical with control over spatiotemporal parameters and dosage.