Preface: Multiphoton Microscopy

Two-photon excitation microscopy (also referred to as multiphoton laser scanning microscopy) has gained increasing popularity during the past few years because of the distinct advantages over single-photon microscopy, which includes increased penetration depth and low out-of-focus photobleaching and photodamage. It allows superior imaging of thick specimen compared to single-photon microscopy, and it excels at imaging live cells either single or within intact tissue. This highly valuable tool has been used with great success to gain important new insights into brain tissue, embryos, whole organs, entire animals, and it has been most useful in numerous other applications.