Hydrocephalus in medical practice is characterized as dropsy in the brain. This condition indicates excessive accumulation of cerebrospinal fluid in the cranial cavity.
Normally, there is a constant circulation of cerebrospinal fluid. The substance in the spinal cord and brain is washed on all sides by a clear, colorless liquid that has various properties, the main of which are protection and providing additional nutrition. External cerebrospinal fluid circulation in the brain occurs between the vascular and soft membranes along the entire surface of the hemispheres and cerebellum. This surface is called subarachnoid space. In the cranial base under the brain there are several more areas of fluid accumulation. They are called tanks. These areas, connecting with each other in different directions, form the cerebrospinal subarachnoid space in the brain and connect to a similar surface in the spinal cord.
In the latter, a channel system and a protective trophic cell system are not provided. The subarachnoid space in the spinal cord behind the posterior roots has a dense skeleton consisting of fibrous fibers interwoven with each other. It should be noted that plexuses are available only here. The lateral subarachnoid space of formations between the dentate ligament and the posterior roots does not. In front of the soft and arachnoid shells are collagen beams that do not interfere with the circulation of cerebrospinal fluid.
Atrophic hydrocephalus is a passive triggered trauma of the replacement of brain matter, which decreases in volume, with cerebrospinal fluid. The condition is characterized by a simultaneous and, as a rule, symmetric enlargement of the ventricles. In this case, the basal cisterns and subarachnoid convexital spaces are expanded against the background of the absence of periventricular edema.
Atrophic hydrocephalus is based on a diffuse atrophic process. Demyelination due to primary brain damage leads to a decrease in both gray and white matter.
The first manifestations of atrophic hydrocephalus can be detected after two or four weeks after a head injury (traumatic brain injury). Subsequently, either a long progression of the process, or its stop, is noted.
Specialists classify a mild, moderate or severe form of the disease.
In the first case, moderate cerebral atrophy is noted , in which there is a slight expansion in the subarachnoid grooves and crevices - by one or two millimeters, as well as in the ventricular system.
The average degree of the disease is characterized by more significant changes - the expansion in the subarachnoid grooves and crevices by three to four millimeters. In addition, a widespread decrease in density in the brain tissue of a moderate nature is possible.
A severe degree of the disease is characterized by a significant expansion in the ventricular system (CVI more than 20.0), in subarachnoid grooves and crevices - over four millimeters. In addition, there is a generalized decrease in density in the brain tissue.
It should be noted that the morphological severity and clinical manifestations of atrophic hydrocephalus are not parallel.
Accurate diagnostics are performed using CT and MRI. The simultaneous and symmetric expansion of the subarachnoid space in combination with an increase in the cerebral ventricles, the absence of periventricular edema, no doubt speak in favor of atrophic hydrocephalus.
In the early stages of the development of the disease, it is often possible to form a sufficient and stable compensation for the patient's condition. However, with a stage of the disease that has gone far, the prognosis is very unfavorable.