ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

This review considers the production and absorption of cerebrospinal fluid (CSF) as they relate to intracranial pressure (ICP) in normal individuals and patients with hydrocephalus. It also considers the physics of various types of shunts used to treat hydrocephalus. The hope is that understanding normal and abnormal CSF flow and the physics of shunts will help physicians select the valve mechanism best suited for individual patients with hydrocephalus. CSF formation is constant over a wide range of ICP. In contrast, CSF absorption depends on ICP. There is no drainage if ICP is less than 5 mm Hg, and the rate of absorption is directly proportional to ICP after the opening pressure is reached. The natural valve is a ventricular-sagittal sinus shunt with an opening pressure of 70 mm H2O. More complicated strategies must be considered because of the effects of siphoning related to the routine use of the peritoneum for the treatment of hydrocephalus. The physics of valve designs commonly used in the United States, as reflected by their pressure-flow characteristics, are described. Hard data from randomized control trials on which to base the selection of one valve compared with another are unavailable. However, specific strategies should be considered in a few conditions, such as posthemorrhagic hydrocephalus in the premature newborn in whom valves should be selected based on their ability to drain CSF with high protein and particulate matter and without the need to compensate for siphoning in the small infant. Patients with normal pressure hydrocephalus need valves that have a low opening pressure but that do not lead to extreme low pressure due to siphoning when an erect position is assumed. Finally, patients symptomatic from overdrainage require high-pressure shunts with devices that retard siphoning; they may benefit from valved lumboperitoneal shunts.

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

This article describes a technique for insertion of ventriculoperitoneal and ventriculovenous cerebrospinal fluid (CSF) shunts for treatment of hydrocephalus. There is an evidentiary basis for few of the decisions that must be made in CSF shunt surgery. In matters unilluminated by evidence, popular options that differ from the author's technique receive consideration as well. Computer-assisted image guidance and intraoperative ultrasound deserve further investigation and, perhaps, incorporation into the routine of ventricular catheter insertion and revision.

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The indications, techniques, and complications of ventriculopleural shunt placement are reviewed. A useful alternative for shunting when the peritoneal or vascular spaces are unavailable is provided.

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Over the last few decades, there has been renewed interest in the use of ventriculosubgaleal shunts for the temporary diversion of cerebrospinal fluid in a select group of patients. Although there are a number of alternatives for accessing the cerebrospinal fluid compartment, ventriculosubgaleal shunts may be superior because they are physiologic and provide continuous decompression of the ventricles through a low-morbidity procedure. Ventriculosubgaleal shunts may be the procedure of choice for low-birth-weight infants in whom the placement of ventriculoperitoneal shunts is plagued with complications. This report reviews the indications and technical aspects of ventriculosubgaleal shunt placement.

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Ventricular shunting is the most widely accepted form of treatment of hydrocephalus. The placement of cerebrospinal fluid shunts has become one of the most common procedures in modern neurologic surgery. Despite significant improvements in shunt procedures, shunt complications remain common. These troubles are associated with significant adverse consequences, both medical and economic. Attempts to limit their incidence require a basic knowledge and understanding of the types of shunt failure and their respective management.

ISSN:1077-2855    

出版商:OVID    

年代:2002

数据来源: OVID