Endoscopic third ventriculostomy in the treatment of shunt-related over-drainage: Preliminary experience with a new approach how to render ventricles navigable

Outcomes of Endoscopic Third Ventriculostomy in Pediatric Patients With Hydrocephalus

Background

Endoscopic third ventriculostomy (ETV) is used to treat patients with obstructive hydrocephalus in infants. This study evaluated the postoperative outcomes of ETV among pediatric patients.

Methodology

A retrospective study was undertaken at the Mardan Medical Complex between June 2018 and June 2021. All pediatric patients who underwent the procedure of ETV in both the absence and presence of choroid plexus cauterization (CPC) at our center were included in the study. Using medical history data, a comprehensive survey questionnaire was designed. The findings and effects were evaluated either as a success or failure.

Results

A total of 90 cases were reviewed during the study. The rate of in-hospital mortality was 1.1% while the most commonly identified causes of hydrocephalus were myelomeningocele and aqueductal stenosis. A total of 39 (43.33%) patients had a successful surgery. In patients where hydrocephalus was secondary to aqueductal stenosis, the success rate was the highest, while the success rate was quite low for post-infectious hydrocephalus and intraventricular hemorrhage (p < 0.0001). The postoperative complication rate was 55.56% in our study. The rate of in-hospital mortality was 1.1%.

Conclusions

We found that the success rate of ETV was dependent upon factors such as the cause of hydrocephalus, type of hydrocephalus, and the age of the patient. Therefore, ETV is not suitable for all patients, and vigilance must be undertaken in selecting patients for the procedure. The rate of postoperative infections in our institution was alarmingly high which is a concerning matter for the institution.

Endoscopy in the treatment of slit ventricle syndrome

The present study aimed to investigate the efficacy of endoscopy in the treatment of post-shunt placement for slit ventricle syndrome (SVS). Endoscopic surgery was performed on 18 patients with SVS between October 2004 and December 2012. Sex, age, causes of the hydrocephalus, ventricular size and imaging data were collected and analyzed. All patients were divided into two groups according to ventricular size and underwent endoscopic surgeries, including endoscopic third ventriculostomy (ETV), endoscopic aqueductoplasty and cystocisternostomy. All treated patients were observed postoperatively for a period of 2 to 3 weeks, and outpatient follow-up was subsequently scheduled for >12 months. Clinical results, including catheter adherence, shunt removal and complications, were analyzed during the follow-up period. The success rate of endoscopic surgery was indicated to be 82.7%. Syndromes caused by aqueductal stenosis in 15 patients who underwent ETV were relieved; however, syndromes in the 3 patients with cerebral cysticercosis, suprasellar arachnoid cysts, pinea larea glioma and communicating hydrocephalus, respectively, were not relieved and underwent shunt placement again. Brain parenchyma, choroid plexus and ependymal tissue were the predominant causes for catheter obstruction and the obstruction rate was indicated to be 77.8% (14/18). Complications, such as pseudobulbar paralysis, infection and intraventricular hemorrhage arose in 3 patients. The present study indicates that endoscopic treatments are effective and ETV may be considered as a recommended option in the treatment of post-shunt placement SVS in hydrocephalus patients.

Endoscopic third ventriculostomy

Endoscopic third ventriculostomy (ETV) is considered as a treatment of choice for obstructive hydrocephalus. It is indicated in hydrocephalus secondary to congenital aqueductal stenosis, posterior third ventricle tumor, cerebellar infarct, Dandy-Walker malformation, vein of Galen aneurism, syringomyelia with or without Chiari malformation type I, intraventricular hematoma, post infective, normal pressure hydrocephalus, myelomeningocele, multiloculated hydrocephalus, encephalocele, posterior fossa tumor and craniosynostosis. It is also indicated in block shunt or slit ventricle syndrome. Proper Pre-operative imaging for detailed assessment of the posterior communicating arteries distance from mid line, presence or absence of Liliequist membrane or other membranes, located in the prepontine cistern is useful. Measurement of lumbar elastance and resistance can predict patency of cranial subarachnoid space and complex hydrocephalus, which decides an ultimate outcome. Water jet dissection is an effective technique of ETV in thick floor. Ultrasonic contact probe can be useful in selected patients. Intra-operative ventriculo-stomography could help in confirming the adequacy of endoscopic procedure, thereby facilitating the need for shunt. Intraoperative observations of the patent aqueduct and prepontine cistern scarring are predictors of the risk of ETV failure. Such patients may be considered for shunt surgery. Magnetic resonance ventriculography and cine phase contrast magnetic resonance imaging are effective in assessing subarachnoid space and stoma patency after ETV. Proper case selection, post-operative care including monitoring of ICP and need for external ventricular drain, repeated lumbar puncture and CSF drainage, Ommaya reservoir in selected patients could help to increase success rate and reduce complications. Most of the complications develop in an early post-operative, but fatal complications can develop late which indicate an importance of long term follow up.

Cerebrospinal fluid dynamics and long-term survival of the Strata valve in idiopathic normal pressure hydrocephalus

OBJECTIVE

Cerebrospinal fluid (CSF) dynamics and long-term shunt survival of the Strata CSF shunt were evaluated in patients with idiopathic normal pressure hydrocephalus (INPH).

SUBJECTS AND METHODS

Seventy-two patients with INPH received a Strata valve. A CSF infusion test, neuroimaging and video recording of gait were performed at baseline and at 6 months (n = 68) after surgery. Long-term shunt survivals were obtained from patient records.

RESULTS

The shunt survival at 1 year was 94% and at 3 years 92.5%. Forty-nine patients (72%) had an improved gait. Two patients were improved despite non-functioning shunts, indicating a possible placebo response. Nineteen patients were not improved at the 6-month follow-up. The shunt tests revealed a functioning shunt in 12; thus, unnecessary shunt revisions could be avoided. Seventeen patients showed a siphoning effect. Shunt revisions were made in six patients. Eight hygromas/subdural hematomas were found.

CONCLUSIONS

The long-term survival of the Strata valves was good, and a concern of complications is not a reason to exclude elderly with INPH from shunt surgery. Studies are needed to evaluate pros and cons of the anti-siphon device. Using a CSF shunt test, unnecessary shunt revisions may be avoided.

Stereotactic versus endoscopic surgery in periventricular lesions

OBJECT

Endoscopic and stereotactic surgery have gained widespread acceptance as minimally invasive tools for the diagnosis of intracerebral pathologies. We investigated the specific advantages and disadvantages of each technique in the assessment of periventricular lesions.

METHOD

This study included a retrospective series of 70 patients with periventricular lesions. Endoscopic surgery was performed in 17 patients (mean age, 37 years; range, 4 months-78 years) and stereotactic biopsy in 55 patients (mean age, 63 years; range, 23-80 years), including two patients who underwent both procedures.

RESULTS

Hydrocephalus was present in 13/17 patients in the endoscopic group (77%) and in 11/55 patients in the stereotactic group (20%). Diagnosis was achieved in all patients in the endoscopic group and in all but one patient in the stereotactic group, in whom histological diagnosis was obtained by endoscopic biopsy during a second operation. In the endoscopic group, additional procedures performed included ventriculostomy (2/17), cyst fenestration (3/17), endoscopic shunt revision (3/17) and placement of Rickham reservoirs or external cerebrospinal fluid drains (6/17). Adverse events occurred in one patient after endoscopy (chronic subdural hematoma) and in two patients after stereotactic surgery (one mild hemiparesis and one transitory paresis of the contralateral leg).

CONCLUSIONS

Endoscopic and stereotactic surgery have distinct advantages and disadvantages in approaching periventricular lesions. The advantages of endoscopy encompass the possibility to perform additional surgical procedures during the same session (e.g. tumour reduction, third ventriculostomy, fenestration of a cyst). The visual control reduces the hazard of injury to anatomical structures and allows for a better control of bleeding although there is a considerable blind-out in such situations. The advantages of stereotactic surgery include a smaller approach and precise planning of the trajectory. It is usually performed under local anaesthesia. Both methods provide a safe and efficient therapeutic option in periventricular lesions with low surgical-related morbidity.

Shunt dependence: myths and facts

INTRODUCTION

Chronically shunted patients are believed to be unable to have a shunt-free life. Nevertheless, sometimes shunt removal is possible after an endoscopic third ventriculostomy, even after long periods of cerebral spinal fluid diversion.

RESULTS AND DISCUSSION

We perform a literature review that leads to a discussion of this subject in the light of the current medical knowledge.