Cerebrospinal fluid dynamics with its surgical implications

Cerebrospinal fluid (CSF) is largely (70-80%) produced by the choroids plexus of the ventricles and is considered as the plasma ultrafiltrate. While CSF formation, circulation, and composition appear to be physiological and physical, its absorption appears to be mainly physical. The formation, composition, circulation, absorption, and changes in pathological conditions of CSF are discussed briefly in this review article. The CSF pressure dynamics studies provide information about the tightness, elastance, or outflow resistance of the CSF in the CNS. We believe that the present study shall help to provide essential details of CSF physiology which are important to many disciplines including radiology, neurology, and neurosurgery.

A Mathematical Model to Simulate Intracranial Pressure and Unified Interpretation of Several Disease Entities

BACKGROUNDMany clinical phenomena related to cerebrospinal fluid(CSF) and intracranial pressure (ICP) are often contrary to common sense and difficult to explain by classical theory. Such as slit ventricle syndrome, normal intracranial pressure hydrocephalus / low pressure hydrocephalus, paradoxical herniation, and so on. Many authors have different theories about them but can’t have an unified explanation.OBJECTIVEWe try to simulate the above CSF disorders and ICP conduction with a mathematical method, and make theoretical interpretations to them.METHODSWe introduced a mathematical model based on several well-accepted hypothesesto simulate human CSF physiology and propose that ICP curve should be an U-shaped curve (especially, we introduce the hypothesis that CSF also play a role of decompression). Maple software was used to draw charts according to our formula. We use the theory and intuitive charts to explain those illnesses one by one.RESULTSThe formula: ICP = μ · MAP − δ · Vα · μ · MAP + θ · Vβ · μ · MAP + C, and corresponding diagrams was conducted.CONCLUSIONThis mathematical model is a supplement to the classical Monro-Kellie’s theory, the curve and coordinate system can be used to analyze different pathophysiological states and give a reasonable unified explanation to them.

Shunt technology and endoscopic ventricular surgery

The management of cerebrospinal fluid (CSF) disorders via CSF diversion is now a complex clinical science, requiring a detailed understanding of CSF physiology in both the normal and diseased brain. Successful treatment of this group of disorders requires a comprehensive knowledge of all the available shunt types, their similarities, differences, and idiosyncrasies. The rapid development of endoscopic neurosurgical techniques makes treating this group of patients without a shunt often a real possibility, and arguably is now a core neurosurgical skill. In this chapter we will summarize the CSF physiology in the normal state, and explain the principles of CSF diversion before going on to describe the various shunt types available. A section will be devoted to endoscopic CSF diversion techniques, including a detailed explanation of third ventriculostomy.