84 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Figure 2. Mild scaling of the nondandruff scalp revealed by ether delipidization A method found useful for estimating the extent of dandruff consists of applying ether in a cup to the scalp for one minute. The replacement of lipids by air scatters light and the scales become prominent (Figs. 1 and 2). Experience teaches that a single estimate on unprepared subjects is unreliable. Final judgment was rendered only after the following base- line procedure: The subjects were washed every 4 days with Ivory soap for 12 days with clinical appraisal just before each washing. Noth- ing else was applied to the scalp antibacterial soaps were avoided. This 4-day washing regimen was standard procedure throughout each study. The subjects were healthy adult males between the ages of 20 and 4½). Ilistopathology It is surprising that a condition as common as dandruff has not been throughly studied in respect to its microscopic peculiarities, yet no clear picture of the histopathology of dandruff has emerged.

OBSERVATIONS ON DANDRUFF 8• -.... .... • ' - • ..•1 .•1•' '• . • • • . : - - . "•,. '-: • • - .• •.• • -'• .. .... • .•'• •. • .... . ..• .:• •'••'• •. ...... -. •. . . -• . ,., .: .. •- • .... • '• .... •... • •'-.• a• •.-•' ..:• .:' -. - ...•.: •:2•. :., ,••,• -.: .... •--•.•'• • •. .• ..... --...-• • • •' • - • . . . • .-:= • - . - . . • • - w •:- . .. . . • • : .• q .. • q.... .:.. • • • ß ,• . .• . . . .. .[.•.. • : • • . • . ß • • .... •- . . . m • ...-• .... -' • • • . • -,. .-• '- •.- •- ß:, - • ß :• .... ß . - i• - . Figure 3. Perivenular lymphohistiocytic infiltrate and apparent epidermal hyperplasia in a nondandruff specimen demonstrating that aggregates of chronic inflammatory cells may be present on the normal scalp Full thickness excisional biopsies were secured from the mid-parietal areas of 13'5 scalps. Twenty of these were normal the rest had heavy dandruff. The specimens were fixed in formalin and stained with hematoxylin and eosin. Additionally, about a third were stained with (a) PAS for glycogen and (b) Hale-Orcein for elastic fibers and acid mucopolysaccharide. One of us (AMK) evaluated the slides without knowing their source. In describing the results of such a survey, which necessaril• deals with subjective appraisals, awareness of the following features is essential to a proper understanding. Firstly, histologic processing invariably distorts and disrupts the horny layer often much of it is lost in section- ing. Accordingly, histologic evaluation of the horny layer has limited usefulness. Secondly, in searching for evidence of inflammatory changes, especially infiltration of the dermis by mononuclear cells., one is occa-