TOWARDS COMPUTER-ASSISTED EVALUATION OF PLAGIOCEPHALY

Plagiocephaly is a common asymmetry of the skull giving the impression that the subject, usually a neonate, has suffered a compressive force acting unilaterally. Normally innocuous, it is a postural deformity t hat can be suggestive of other significant abnormalities, e.g. joint d ysplasia. Although intuitive measurements of plagiocephaly appear in t he literature there is little evidence of analytical evaluation. This paper describes a measurement methodology based on black and white pho tography. A flat-bed scanner and a personal computer facilitated the t ransformation of the prepared photograph to standard tagged image file format at 256 grey scale. A utility was used to convert the file scan to a monochrome bitmap image which was displayed on the screen and su bjected to an algorithm to compute the centroid of the cranial profile . Radials that emerge from the centroid to the cranial circumference a t five degree intervals map to a signal display that represents the pl agiocephaly.