Use of CT in detection of internal damage and repair and determination of authenticity in high-quality bowed stringed instruments.

Computed tomography (CT) was used to evaluate 17 high-quality violins and cellos crafted between 1633 and 1872 by master craftsmen such as Guarneri, Amati, and Stradivari. Multiple high-resolution CT scans were obtained in each instrument, and additional scans were obtained when defects or repair was detected. Varying degrees of internal damage (eg, wormholes, air gaps, plastic deformities of wood) or repair (eg, glue lines, filler material, wooden cleats and patches) not seen at visual inspection were detected in all 17 instruments. In addition, CT allowed noninvasive identification of the internal wood grain pattern unique to each instrument, thereby facilitating verification of authenticity to help protect against loss, theft, or forgery. The information provided by CT analysis of valuable bowed stringed instruments may prove useful to prospective buyers or to insurance companies that specialize in insuring such instruments against accidental loss or damage.