A Device for Automatic Punch Biopsy and Simultaneous Wound Closure

Punch biopsy is a skin biopsy method that is used to remove a small sample of the epidermis and dermis. The procedure requires a trained dermatologist to excise the sample with a punch biopsy tool and then immediately apply sutures for wound closure. Punch biopsy is a common procedure necessary for the diagnosis of many conditions. Thus, the present shortage of dermatologists-especially in the developing world-motivates the design of convenient methods for punch biopsy that do not require clinical training. Here, we present a medical device that streamlines punch biopsy and wound closure into simple, sequential operations. The handheld device engages and securely locks the skin, excises the biopsy sample, then applies a N-butyl cyanoacrylate tissue adhesive for wound closure. The device is validated ex vivo using porcine ear skin, which has comparable biomechanical properties to human skin. For engagement, the device can target the desired biopsy area with an accuracy of 2 mm. For sample collection, the device reliably excises samples 7 mm in diameter and 4 mm in depth. For wound closure, the device streamlines the application of tissue adhesive to seal the wound, albeit with less strength than surgical sutures. Altogether, these results validate the design of a device for punch biopsy and wound closure that can be used within sequential steps with minimal training.