A clinical comparison of subdural screw pressure measurements with ventricular pressure.
Simultaneous recordings of intracranial pressure (ICP) from a single-lumen subdural screw and a ventricular catheter were compared in 10 patients with severe head injury. Forty-one percent of the readings corresponded within the same 10 mm Hg ranges, while 13% of the screw pressure measurements were higher and 46% were lower than the associated ventricular catheter measurements. In 10 other patients, also with severe head injury, pressure measurements obtained with the Leeds-type screw were similarly compared with ventricular fluid pressure. Fifty-eight percent of the dual pressure readings corresponded, while 15% of the screw measurements were higher and 27% were lower than the ventricular fluid pressure, within 10-mm Hg ranges. It is concluded that subdural screws may give unreliable results, particularly by underestimating the occurrence of high ICP.
D002552:Cerebral Ventricles; D006259:Craniocerebral Trauma / Q000503:physiopathology; D006801:Humans; D007427:Intracranial Pressure; D008578:Meninges; D008722:Methods; D013355:Subdural Space; D013525:Surgical Instruments