Transcutaneous pressure adjustable valve for the treatment of hydrocephalus and arachnoid cysts in adults

Abstract

The authors report a series of 75 adults treated over the last four years for hydrocephalus (69 cases) or arachnoid cysts (6 cases) by using a transcutaneous pressure adjustable valve (Sophy SU 8), the mechanism of which is recalled. The shunt was ventriculo-atrial 46 times, ventriculo-peritoneal 23 times and cysto-peritoneal 6 times. The opening pressure of the valve was initially adjusted 56 times to the medium, 9 times to the high, and 10 times to the low position, according to each particular patient's needs. Following the evolution of the neurological status and/or the CT findings, the opening pressure was secondarily modified in 27 patients (i.e., in 36%), and in some of them several times. It was raised 16 times: 10 times because of subdural hygroma(s) (complicated by a subdural haematoma which required surgical removal, in one case), and 6 times because of clinical symptoms of intracranial hypotension associated with hyperdrainage signs on CT. It was diminished 20 times because of the absence of clinical improvement and persistence of dilated ventricles on CT. In these 27 patients the Sophy SU 8 valve allowed modification of its opening pressure according to the clinical and CT evolution, without need for re-operation. It is concluded that the patients who can benefit most from this valve system are patients with normal pressure hydrocephalus or with arachnoid cysts.

Guidelines for Management of Idiopathic Normal Pressure Hydrocephalus: Second Edition

“…28,50,62,117,138) Evans index (ratio of the maximum width of the frontal horns to the maximum width of the inner table of the cranium) of greater than 0.3 is a hallmark of hydrocephalus. The subarachnoid spaces in the sylvian fissures and over the ventral surface below are dilated (or at least not narrowed), and those over the high cerebral convexity and medial surface are narrowed 55,62,81,117,142) (Figs. 4 and 5).…”

“…It should be kept in mind that some of the elderly may present with MRI features consistent with DESH without neurological symptoms, which is called AVIM. 21) The finding of tight high convexity subarachnoid spaces can differentiate iNPH from cerebral atrophy in patients with Alzheimer's disease with high sensitivity and specificity 55,62,142) …”

“…To date, several studies have used CSF dynamic tests (e.g., CSF outflow resistance) or ICP monitoring designed to develop a method for setting the initial postoperative valve pressure 55,60,67) ; however, in all of these studies, there was a high readjustment rate, raising the question as to the validity of these strategies. Only one study, which was based on measurements in the upright position, has demonstrated satisfactory outcomes using a quantitative strategy for determining the initial pressure settings.…”

“…18) There have been no studies comparing the CodmanHakim Programmable Valve } , Sophy Valve } , and fixed-pressure valves, and superiority among the valves remains to be determined. However, reports have shown that there are no major differences between the valves in terms of complication rates of infection 30,51,55,68) or shunt occlusion. 32,55,56,67) However, the use of antibiotics during the perioperative period has been shown to reduce the incidence of infection.…”

“…However, reports have shown that there are no major differences between the valves in terms of complication rates of infection 30,51,55,68) or shunt occlusion. 32,55,56,67) However, the use of antibiotics during the perioperative period has been shown to reduce the incidence of infection. 67) Complications of nontraumatic subdural hygroma/hematoma were reported to improve by resetting to higher pressures in the Codman-Hakim Programmable Valve } and Sophy Valve } , and evacuative operations were only required in 2.7% of cases using the Codman-Hakim Programmable Valve } 51,68) and 1.4% using the Sophy Valve } .…”