(From deprimo, to press down). A depression. In surgery this word generally signifies a sinking of some part of the skull, which happens from an external violence, by which the bone is fractured, or pressed inwards. This injury is sometimes named impressio, introcessio.
In this case, the same symptoms may attend as are observed in an extravasation within the skull, and are caused by the same means, viz. mechanical pressure: they differ widely from those of a concussion of the brain. See Concussio, Extravasatio, Cerberi, Compressio.
Dr. Hunter seems to think, that it is almost impossible to raise a depression of this kind, because the fracture is usually more extensive in the inside than externally, and the spiculae can never be brought exactly to fit each other. But as, according to Hildanus and Van-der Weil, some skulls have been depressed without fracture, success may be expected, at least, in some cases; and where the bones are soft and yielding, they may be raised by means of a string fastened to an adhesive plaster, which may be applied to the depression, after shaving the part. But, after all, if their elevation were easily practicable, it would not be advisable, in general, to be contented with mere elevation; for all the ills attending and succeeding simple fractures, are more likely to happen from depressed pieces of bone; therefore the depressed pieces should be generally removed.