Transillumination in neonatal diagnosis.

Transillumination is a safe, nonionizing, and noninvasive diagnostic technique that is particularly well-suited for use in the newborn. In addition, its portability, minimal expense, and facility make it a useful and necessary tool for the neonatal intensive care unit. This article reviews the principles of transillumination, describes equipment currently in use, and summarizes the clinical applications of transillumination.