Ultrasonic Observation of the Nail Matrix

BACKGROUND: The authors made use of echograms for the observation of the nail matrix. OBJECTIVE: To inspect the nail matrix and identify what causes nail plate deformities. METHODS: A 30-MHz frequency high-resolution B-mode was applied to normal and damaged nails. RESULTS: Clear shadows of underlying nail plates were observed beneath the proximal nail fold. Some cases with nail plate deformities showed damaged sub-proximal fold nail plates, which would indicate nail matrix deformities. CONCLUSION: The echograms had diagnostic value to nail plate deformities. If a normal echogram is obtained at the proximal nail fold, the nail bed will be the place at which the nail deformities occur. If the echogram indicates any sub-proximal fold nail plate changes, the damaged nail matrix may be attributable to the nail deformities. Echograms also gave clear echoic shadows of subungual tumors. That contributed to identifying the infiltrating border of subungual malignant melanomas around the nail matrix noninvasively.