Clinical Follow-Up Study for Sphera DuoŽ Hydrocephalus Shunt

Special Article – Neuro Surgery

Austin J Surg. 2018; 5(4): 1134.

Clinical Follow-Up Study for Sphera Duo® Hydrocephalus Shunt

Pinto FC, Oliveira MF*, Nespoli VS, Castro JPS, Morais JVR, Pinto FMG and Teixeira MJ

Group of Cerebral Hydrodynamics, Division of Functional Neurosurgery, University of São Paulo, Brazil

*Corresponding author: Matheus Fernandes de Oliveira, Group of Cerebral Hydrodynamics, Division of Functional Neurosurgery, Institute of Psychiatry, Hospital das Clínicas, University of São Paulo, Rua Loefgren, 700, apto 103, Vila Clementino, São Paulo, CEP 04040-000, Brazil

Received: December 19, 2017; Accepted: February 19, 2018; Published: February 26, 2018

Abstract

Cerebral hydrodynamics complications in shunted patients are due to malfunction of the system. The objective of this retrospective, single-center, single-arm cohort study is to confirm safety and performance of Sphera® Duo when used in adult patients suffering from hydrocephalus, pseudotumor cerebri or arachnoid cysts. Data were generated by reviewing 55 adult patient’s charts that were submitted to a ventriculoperitoneal shunt surgery and followed for one year after surgery. The result shows us that 85.4% of the patients improved the neurological symptoms and the reoperation rate was 12.5% in the first year after surgery.

Keywords: Ventriculoperitoneal shunt; Complications; Reoperation; Outcome

Introduction

Hydrocephalus, pseudotumor cerebri and aracnoid cysts are the main causes of cerebral hydrodynamics disturbance in adults. The surgical treatment is attained through the implantation of ventricular (to peritoneum, atrium or pleural cavity) shunt system, neuroendoscopy or both for neurological improvement [1,2].

In 1997, the United Kingdom Shunt Registry showed in 13,206 adults with hydrocephalus submitted to ventriculoperitoneal shunt (VP) implantation that 22% of all patients required reoperation within five years [3].

Cerebral hydrodynamics complications in shunted patients are due to malfunction of the system. If the shunt malfunctions and if the mechanism causing the cerebral hydrodynamics disturbance is still active, symptoms of hydrocephalus, pseudotumor cerebri or arachnoid cyst recur, and a shunt revision or other drainage procedure are required [1,2,4,5].

Malfunction may be caused by infection or mechanical failure. Approximately 40% of standard shunts malfunction occur within the first year after placement and 5% per year malfunction in subsequent years [4].

The objective of this study was to confirm safety and performance of Sphera® Duo when used in adult patients suffering from hydrocephalus, pseudotumor cerebri or arachnoid cyst.

Methods

This is a retrospective, single-center, single-arm cohort study approved by the Institutional Ethics Committee. The data are generated by reviewing 55 adult patient’s charts who were submitted to a VP shunt surgery for the treatment of cerebral hydrodynamics disturbs (hydrocephalus, pseudotumor cerebri or arachnoid cyst), from January 2015 to July 2016 at Instituto de Psiquiatria do Hospital das Cliacute;nicas da Faculdade de Medicina da Universidade de São Paulo. The SPHERA DUO® (HPBio, Brazil) shunt was used in all cases.

The SPHERA DUO® is a fixed pressure valve which works through a sequential double coil spring mechanism, seat and ruby sphere. According to the characteristic of the springs, three ranges of pressure difference ensure a flow of 21 mL/h, which corresponds to the physiological CSF production: low (3 to 7 cm H2O), medium (7 to 11 cm H2O) and high (11 to 14 cm H2O).

Primary endpoints

Frequency and severity of complications or side effects occurring in one year observation period following implantation are recorded.

Secondary endpoints

Clinical improvement after one year of shunt implantation: resolution of the intracranial hypertension syndrome (hydrocephalus, pseudotumor cerebri or arachnoid cyst) or improvement of Normal Pressure Hydrocephalus (NPH) triad (gait apraxia, memory alterations and urinary incontinence).

Study population

Inclusion criteria: Patient has received ventriculoperitoneal, ventriculoatrial or ventriculopleural shunt by implanting the SPHERA DUO® hydrocephalus shunt system.

Patient has been followed according the institutional preestablished routine in-patient and out-patient visits.

Age > 16 years old

Exclusion criteria: The patient received only the shunt (not the entire system - ventricular and peritoneal catheter) to treat a diagnosed over drainage in the previous implanted shunt of another brand.

The patient was treated by ventriculitis with Extraventricular Drainage (EVD) shortly before the implantation of the SPHERA DUO® hydrocephalus derivation system

Surgical procedure

The standard VP shunt implantation technique applied in our service is composed of cranial and abdominal approaches and is not different from the technique described by Choux et al. [4]. After initial approaches, we perform identification of peritoneum and catheterization of lateral ventricles. Simultaneously we create a subcutaneous tunnel to allow the passage of distal catheter. The whole system is attached and wounds are closed with tight suture.

Results

In the period of 1 year and 6 months (from January 2015 to July 2016), 252 surgeries were performed by the Group of Cerebral Hydrodynamics. Of these, 55 were included in this study according to the established criteria for structuring this cohort.

Twenty-five patients are male (45%) and 30 female (55%). The distribution of ages is represented in (Figure 1), with the youngest patient being 16 years old and the oldest being 90 years old. The most commonly treated cerebral hydrodynamic disorder is acquired hydrocephalus, accounting for 80% of cases (Figure 2), and normal pressure hydrocephalus constitutes about 60% of this sample (Figure 3). Thirty-seven valves were of medium pressure (67%), 13 of high pressure (23%) and 5 (10%) of low pressure valves were implanted according to (Table 1).