• Evaluating longitudinal changes of gait parameters following shunt placement in patients with idiopathic normal pressure hydrocephalus
• Neurocognitive effects of CSF biomarkers in idiopathic normal pressure hydrocephalus patients undergoing VP shunt placement
• Value of biomarkers in the prediction of shunt responsivity in patients with normal pressure hydrocephalus
• Extended lumbar drain trials for diagnostic evaluation of idiopathic normal pressure hydrocephalus with the Berg Balance Scale
• The Effects of Endoscopic Third Ventriculostomy Versus Ventriculoperitoneal Shunt on Neuropsychological and Motor Performance in Patients with Idiopathic Normal Pressure Hydrocephalus-ENVENTOR-iNPH: Study Protocol
• Programmable gravitational valves in idiopathic normal pressure hydrocephalus: long-term outcomes after a 3-year follow-up
• Advancing treatment strategies for idiopathic normal pressure hydrocephalus: a systematic review on studies comparing ventricular and lumbo-peritoneal shunts
• Idiopathic normal pressure hydrocephalus: associations between CSF biomarkers, clinical symptoms, and outcome after shunt surgery

• Diagnosed iNPH with positive clinical features
• Radiological evidence of ventriculomegaly (Evans index > 0.3)
• Positive response to CSF tap test or extended lumbar drainage
• Exclusion of other causes (e.g., Alzheimer's disease, Parkinsonism)

1. A silicone catheter is placed into the lateral ventricle
2. It is connected to a programmable valve
3. CSF is drained into the peritoneal cavity via distal tubing
4. Valve settings can be adjusted non-invasively post-op

Outcome after ventriculoperitoneal shunt for idiopathic normal pressure hydrocephalus

Ventriculoperitoneal shunt complications

• Serial clinical and neuroimaging assessments
• Adjustment of valve pressure based on symptoms and radiological findings
• Long-term monitoring for delayed complications

• Lumboperitoneal shunt (less invasive, but higher revision rate)
• Endoscopic third ventriculostomy (rarely used in iNPH)

On the basis of a multicentre prospective randomized trial it is to be recommended to treat patients with idiopathic normal pressure hydrocephalus with a shunt with an adjustable valve, preset at the highest opening pressure and lowered until clinical improvement or radiological signs of overdrainage occur although slower improvement and more shunt adjustments might be the consequence ¹⁾

A permanent CSF diversion with a ventriculoperitoneal shunt (VPS) is a treatment option for patients with idiopathic normal pressure hydrocephalus. An improvement of symptoms is seen in 70% to 85% of patients after shunting ²⁾.

Complication rates may be as high as ≈ 35% (due in part to the frailty of the elderly brain). Potential complications include:

1. subdural hematomas or hygroma: higher risk with low-pressure valve and older patients who tend to have cerebral atrophy. Usually accompanied by a headache, most resolve spontaneously or remain stable. Approximately one–third require evacuation and tying off of the shunt (temporarily or permanently). The risk may be reduced by gradual mobilization post-op

2. shunt infection

3. intracerebral hemorrhage

4. seizures

5. Delayed complications include the above, plus shunt obstruction or disconnection

• Preoperative imaging biomarkers combined with tap test for predicting shunt surgery outcome in idiopathic normal pressure hydrocephalus: a multicenter retrospective study
• Neuroimaging predictors of favorable outcomes after shunting procedures in patients with Hakim-Adams syndrome: a pilot prospective randomized trial
• Gait characteristics in idiopathic normal pressure hydrocephalus: a review on the effects of CSF tap test and shunt surgery
• Electromagnetic Navigation Improves Accuracy and Reduces Complications of Ventriculoperitoneal Shunts in Patients with Idiopathic Normal Pressure Hydrocephalus: A Single-Center Clinical Experience
• Intrascopic predictors of favorable outcomes after ventriculoperitoneal shunting in Hakim-Adams syndrome: a single-center retrospective non-randomized study
• Changes in Callosal Angle and Evans Index After Shunt Surgery in Patients with Idiopathic Normal Pressure Hydrocephalus
• Artificial Intelligence for Automatic Analysis of Shunt Treatment in Presurgery and Postsurgery Computed Tomography Brain Scans of Patients With Idiopathic Normal Pressure Hydrocephalus
• Usefulness of third ventricle volumetry in patients with normal pressure hydrocephalus

Purpose:

• Confirm ventricular catheter placement.
• Detect postoperative hemorrhage (intraparenchymal, subdural, intraventricular).
• Check for pneumocephalus or other complications.
• Compare ventricular size with preoperative imaging.

In the non-contrast brain CT image, the ventriculoperitoneal shunt catheter is clearly visible, inserted into the frontal horn of the right lateral ventricle.

Regarding the distance between the catheter tip and the foramen of Monro:

The foramen of Monro (or interventricular foramen) is located approximately at the midline, at the junction between the frontal horn and the body of the lateral ventricle, near the thalamic plane.

In this axial image, the catheter tip is located within the frontal horn, anterior and slightly lateral to the foramen of Monro.

Approximate visual estimation: the catheter tip is at a distance of about 1.5 to 2 cm from the foramen of Monro, following the anteroposterior axis of the lateral ventricle.

Purpose:

• Visualize the entire shunt system.
• Detect catheter disconnection, kinking, or migration.
• Confirm peritoneal tip location.

Purpose:

• Evaluate for change or stabilization in ventricular size.
• Assess periventricular edema or transependymal CSF flow.
• Rule out delayed complications.
• Correlate radiological findings with clinical improvement.

Modalities:

• Radionuclide shunt study.
• Phase-contrast MRI for CSF flow.

Purpose:

• Confirm shunt patency.
• Quantify CSF dynamics.

Note: This protocol may vary depending on hospital resources and patient-specific factors.