VENTRICULAR CHANGES AFTER CLOSED HEAD INJURY.

Introduction ALTHOUGH the majority of patients who sustain a closed head injury appear to make a complete and satisfactory recovery, some are left with residual disabilities, which interfere with their well-being and their adjustment to society. It is known that in such cases permanent structural changes often occur in the brain, but clinically it is difficult to ascertain their severity and extent. There is no single method of investigation which affords this information. Such methods as neurological examination, radiological investigation of the skull, psychological tests, and electro-encephalography, each contribute something to the analysis, but each has its limitations. The following study was undertaken in order to evaluate air encephalography, not so much as a method of demonstrating the presence of posttraumatic space-occupying lesions, but of assessing the degree ofdamage which has occurred in the brain. That changes in the outline of the ventricles often follow closed head injury was clearly established in papers from Foerster's clinic at Breslau by Schwab (1926a and b) and by Bielschowsky (1928). Both authors employed encephalography with air introduced by the lumbar route and both described three groups of cases with abnormal encephalographic findings, viz. (a) cases in which the ventricles did not fill; (b) cases with enlargement and deformity of the ventricles; and (c) cases with abnormalities of distribution of the sub-arachnoid air over the cerebral convexities. In addition both studied the circulation of the cerebro-spinal fluid after head injury by injecting sodium iodide solution into the ventricles or lumbar theca, and subsequently ascertaining the time of its appearance in other parts of the cerebro-spinal fluid system or in the urine. On comparing their findings with standards obtained from control cases, both of them concluded that in the majority of cases with abnormal encephalograms there were disturbances of the cerebro-spinal fluid circulation, either in the form of obstruction to the cerebro-spinal fluid pathways or of delayed absorption of the fluid into the bood stream. Bielschowsky, whose paper was based on 106 cases of head injury, of both closed and open types, went further than Schwab and tried to correlate the clinical features of his cases with the encephalographic appearances. He showed that, while in many cases there was an obvious relationship between the two, in other cases this relationship was not apparent; and indeed the same encephalographic appearances as were seen in some cases with persistent symptoms and signs would also be seen in others without persistent symptoms or with only a history of post-traumatic epilepsy. Since then several other authors have confirmed that encephalographic changes often follow head injury, but without exception they have based their findings on smaller groups of cases and have not extended the scope of Bielschowsky's observations. Fischer (1927), after investigating a series of 14 psychopathic patients, many of whom had sustained head injury several years previously, concluded that similar encephalographic abnormalities could sometimes be found in psychopathic patients who had no history of head injury, and that the correlation between clinical features and encephalographic findings was not always apparent. Swift (1931), Hauptmann (1932), Friedman (1932) and others have regarded encephalography as a means of differentiating between cases with genuine disabilities and cases with functional disturbances, implying that those cases which have normal encephalographic appearances usually belong to the latter group. Several others (Flugel 1932, Bennett and Hunt 1933, Lippens and Desjardin 1934, Travers 1937, Money and Susman 1932), have reported on the encephalographic changes following head injury without offering much comment on their vetiological and clinical significance. There has thus been little advance in our appreciation of the encephalographic changes following head injury since Bielschowsky's paper appeared in 1928. During the intervening years knowledge of the clinical aspects of head injury has much improved. In this paper an attempt is therefore made to reassess, in terms of present-day clinical standards, the value of air encephalography in the investigation of cases of head injury after the acute stage.