[Intracranial distension in neurosurgical pathology]

In contrast to the classic research into the problem of intracranial pressure based on the assumption that pressure in the cranial cavity is distributed uniformly, the initial methodological principle of the present work rests on the concept of the nonuniform distribution of pressure in the intracranial system both in health and disease. Comparative dynamic measurements of cerebrospinal fluid and brain tissue pressures were carried out in the early postoperative period to reveal absolute magnitudes of pressures and their correlations. Under examination were 166 neurosurgical patients with different levels of brain injury. The magnitude of cerebrospinal fluid pressure was demonstrated to depend on the level of brain injury. In the groups examined, intracerebral pressure of interstitial fluid in "normal" brain tissue was approximately the same (from -3 to +2 mm Hg). In brain edema, that pressure increased, sometimes to a considerable measure (up to 50 mm Hg). Neurosurgical pathology was shown to be characterized by nonuniform distribution of pressure in the main intracranial media: brain tissue and cerebrospinal fluid, which disturbs the physiological ratio of these pressures. It should be mentioned that some of the structures are under normal pressure whereas the other ones under elevated or lowered as compared to the physiological norm. Such a state can be correctly characterized by the term "intracranial distension" bearing in mind nonuniformity of tension in the intracranial system, a possible one-staged coexistence in the crane of the areas with elevated, normal and lowered pressures.