Value of the Application of Neuroendoscope in the Treatment of Ventriculoperitoneal Shunt Blockage

Clinical application of 3D slicer reconstruction and 3D printing localization combined with neuroendoscopy technology in VPS surgery

To explore techniques, advantages and disadvantages of 3D Slicer reconstruction and 3D printing localization technology combined with transcranial neuroendoscopy in ventriculoperitoneal shunt surgery. Retrospective analysis of clinical data of patients with hydrocephalus treated by ventriculoperitoneal shunt surgery using 3D Slicer reconstruction and 3D printing positioning technology combined with transcranial neuroendoscopy in our hospital from October 2021 to March 2023. A total of 33 patients with complete data were collected, including 19 males and 14 females, aged 10-81 years. Pre operative use of 3D Slicer reconstruction and 3D printing localization, and intraoperative use of neuroendoscopy assisted catheterization to complete ventriculoperitoneal shunt surgery. The drainage tube position was confirmed by brain CT and 3D Slicer reconstruction after operation, of which 30 cases were located in the frontal horn or center of the ipsilateral lateral ventricle, and 3 cases were located in the frontal horn or center of the contralateral lateral ventricle. All patients were successfully catheterized and well positioned. According to the unique ventricular system characteristics of each hydrocephalus patient, the 3D Slicer reconstruction technology was used to determine the individualized puncture point and direction, measure the puncture depth, accurately locate the puncture through the 3D printing guide plate, and accurately send the tip of the ventricular catheter into the frontal or central part of the lateral ventricle with the assistance of neuroendoscopic visualization, which improved the success rate of the operation and reduced the risk of tube blockage. At the same time, our team has newly developed a puncture point ("Cai's point"), which has a puncture path in a non-vascular area and can reduce the risk of puncture bleeding. However, further prospective clinical research is needed to determine its routine location.

A ventricular catheter that migrated into the fourth ventricle successfully removed using a neuroendoscope

BACKGROUND

In order to remove a foreign body in the ventricle, such as a ventricular drainage catheter, craniotomy and corticotomy are required to access the ventricle. A case in which a catheter in the 4th ventricle was safely removed with a flexible neuroendoscope is reported.

CASE DESCRIPTION

A 47-year-old man underwent coil embolization and ventricular drainage for subarachnoid hemorrhage. 10 days after the operation, he tore off the ventricular drainage catheter and the catheter remained intracranially. The tip of the catheter was in the 4th ventricle and the operation to remove remaining catheter with a neuroendoscope was performed. Using a neuroendoscope, we could remove the catheter safely and did not detect the complications.

CONCLUSION

To date, there have been no reports of cases in which a drainage catheter in the ventricle was removed using a flexible endoscope. This case suggests that a flexible endoscope is useful for removing a foreign body from the ventricle less invasively.

MRI as a one-stop destination for evaluation of CSF shunt malfunction

Background

Despite the high-frequency rate of cerebrospinal fluid shunt malfunction, radiological evaluation of CSF shunts has remained deficient, focusing mainly on demonstrating secondary signs of shunt failure rather than evaluating the shunt tube itself. We aimed to study the utility of different MR pulse sequences in evaluating the cranial and abdominal ends of CSF shunts in order to identify the potential cause of shunt failure and its impact on patient management.

Results

Twenty-five patients (18 males, 7 females, median age 2.5 years, IQR 0.75–15) were enrolled in the study, having 28 ventriculo-peritoneal shunts and single ventriculo-gallbladder shunt. The catheter lumen and fine intraventricular septae were only demonstrated in 3D-DRIVE sequences (p < 0.001). Except for three patients (having cranial end-related complications), all patients with cranial and/or abdominal end-related complications received surgery (p < 0.001, positive likelihood and negative likelihood ratios = 7.27, 0.3, respectively, sensitivity = 0.7 and specificity = 0.9). MRI findings (luminal occlusion, disconnection, CSF collection, or migration) were consistent with operative data. There is no significant difference between patients who underwent surgery and those with conservative management, or symptomatic and asymptomatic patients in terms of the prevalence of ventricular dilatation or white matter signal abnormality. The results of the abdomino-pelvic fat-suppressed T2-WI showed excellent agreement with ultrasound findings (Cohen’s Kappa 0.9). Quantitative PC could give insights into CSF dynamics, which depend on the site and cause of shunt malfunction.

Conclusions

MRI could be a one-stop destination for evaluating patients with suspected non-acute shunt malfunction. It was found to have clinical relevance in terms of accurately locating the exact site and possible cause of shunt-related complications.

Removal of the Retained Ventricular Catheter Using the Endoscopic Monopolar Instrument

Background

Ventriculoperitoneal shunt (VPS) remains the main treatment for hydrocephalus. However, VPS revision surgery is very common. Here, we present a case in which the retained ventricular catheter was removed using the endoscopic monopolar instrument.

Methods

We report a case of a 28-year-old female who presented with VPS obstruction. She had two previous shunt revision surgeries due to shunt obstruction. Eleven years after the last one, she presented an abdominal pseudocyst that indicated a total system removal. During VPS revision surgery, a retained ventricular catheter was observed. The endoscopic monopolar instrument was introduced into the retained catheter under direct view. Coagulations in a back-and-forth movement were applied to release inner catheter adhesions. After these steps, the catheter was removed, and a new one was placed through the same route.

Results

The catheter was removed without complications, confirmed by the postoperative cranial computed tomography. The patient remained asymptomatic.

Conclusion

The described technique was effective and avoided ventricular bleeding. Further studies are necessary to validate this method.

Neuroendoscopic Navigated One-Step Removal of Crossed Ventricular Catheter Fragments: Technical Note

Introduction Neuroendoscopy plays an important role in minimally invasive neurosurgery. The authors reported an interesting case of a pediatric patient with multiple ventriculoperitoneal shunt (VPS) revision surgeries, presenting with VPS infection and with two crossed intraventricular floating catheter fragments, successfully removed through a neuroendoscopic navigated one-step procedure. A literature review regarding this exceedingly rare condition has also been discussed.

Case Description An 11-year-old female patient with a history of congenital hydrocephalus was admitted to the emergency department with symptoms of intracranial hypertension, psychomotor agitation, and tetraparesis. She had a history of previous multiple VPS revisions. She had an urgent brain computed tomography scan that documented hydrocephalus; the VPS's intraventricular catheter tip was sited at the level of the right frontal horn. Two small floating catheter fragments, not connected to the VPS, were identified: the first close to the right lateral ventricle at the level of the right occipital horn, the second one between the right occipital horn and the third ventricle. First, she underwent an exteriorization of the distal catheter for VPS. Cerebrospinal fluid examination documented hyperproteinorrachia and a positive culture for Staphylococcus aureus. Then a navigated right transfrontal endoscopic approach to the right lateral ventricle was performed extending to the previous burr hole and achieving a wide range of working angle with a rigid 0-degree lens endoscope. Intermittent irrigation generating convective flow was performed such as to mobilize the catheters tip gently upward, to remove them by grasping. Finally, a whole VPS replacement has been performed.

Conclusion Persistence of intraventricular floating catheter fragments can lead to subacute or chronic infections. Neuroendoscopic retrieval represents a safe and effective alternative to a more extensive and invasive surgical approach. However, the exact catheter tip identification, grasping, and removal can be difficult to achieve, due to the technical instrumentation characteristics and altered intraventricular anatomy in chronic congenital hydrocephalus. In our experience, endoscopic convective flow induction through saline irrigation can determine floating intraventricular catheter fragments movement aiming to their identification and subsequent successful endoscopic retrieval.