Punch Skin Biopsy
Punch biopsy is considered the primary technique to obtain diagnostic, full-thickness skin samples. It is performed using a circular blade attached to a pencil-like handle. The instrument is rotated down through the skin in order to cut out a suitably sized sample. Large punch biopsy sites can be closed with a single suture and generally produce only a minimal scar. Because linear closure is performed on the circular-shaped defect, stretching the skin before performing the punch biopsy allows the relaxed skin defect to appear more elliptical and makes it easier to close. The skin is stretched perpendicular to the relaxed skin tension lines so that the resulting elliptical-shaped wound and closure are parallel to these skin tension lines. Punch biopsy of inflamed or abnormal areas can provide useful information when determining the condition or disease causing an area like this. Skin samples can be evaluated by punch biopsy, and the discovery of malignancy may alter the planned surgical excision procedure. Routine biopsy of skin rashes is not recommended because the commonly reported nonspecific pathology result rarely alters clinical management.