Office Diagnosis of Changes in Hair Cuticular Cell Patterns

To the Editor.—  During the first three decades of this century, a series of papers reported morphologic investigations of hair showing that the appearance of human hair cuticular cells was related to the diameter of the hair shaft.¹ Subsequently, cosmeticists and clinicians became interested in changes of hair surface patterns² occurring after single or repeated physicochemical insults that can eventually lead to the most severe alteration, trichorrhexis nodosa.³ The introduction of transmission electron microscopy and scanning electron microscopy (SEM) rapidly increased our knowledge about the fine structure of the normal cuticula and how exposure to environmental insults gradually exposed the deeper cell layers of the hair shaft.^4-8 This was soon followed by studies of the physical⁹ and chemical^10,11 properties of the cuticula.It is hard to imagine every practicing dermatologist having his own SEM. Hence, less sophisticated techniques are still welcome to allow a rapid