CASE REPORTS CONGENITAL HEMI-ATROPHY BY

Not much detailed information is available as to the causes and origin of structural asymmetries. Congenital hemi-atrophy is a rare developmental abnormality in which parts or all of one side of body are of diminished size. As a rule all tissues are affected to a similar extent. The condition should not be confounded with the unilateral atrophy associated with motor disorders such as unilateral paralysis and unilateral athetosis. In 1927, in a survey of world literature, starting from 1859, Kraus and Perkins found only eight cases of congenital hemi-atrophy in five of which the whole side of the body was affected. The other three were confined to the leg in two cases, and to the face and leg in one case. More cases have been reported since, and in 1939, in another survey of world literature, Landauer found twenty-two cases of congenital hemi-atrophy, eight of which only showed an affection of the whole side of the body. Congenital hemi-hypertrophy is, in many ways, the counterpart to congenital hemi-atrophy. Although also a rare condition, more cases of hemi-hypertrophy have been reported than of hemi-atrophy. Both conditions are sometimes associated with retardation in mental development and with vasculo-cutaneous disturbances, but these are met with much less frequently in unilateral atrophy than in unilateral hypertrophy. Perhaps these two latter affections are not caused by two different agents, but by either hypo- or hyperfunction of the same agent respectively. The mechanism which brings about preferential asymmetry seems to act during a comparatively early stage of embryonic life. Probably the agency responsible for developmental asymmetry must be looked for within the developing embryo, and not in conditions of the uterine environment, as so many different structures are affected.. Various authors assume that the central nervous system has a trophic function in development and that thus unequal differentiation of cerebral centres may modify growth asymmetrically. Kraus and Perkins hold the view that cerebral portions of the visceral nervous system exert a trophic control not only on glands and smooth muscle but also on striated muscle, tendons, bone, skin, hair, in short, on all tissues of the body. They assume that these centres are located in the hypothalamic region in or about the floor of the third ventricle, as well as in the cel