Table of Contents

Ventriculoperitoneal Shunt in Idiopathic Normal Pressure Hydrocephalus



Indications

Procedure

  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

Outcome after ventriculoperitoneal shunt for idiopathic normal pressure hydrocephalus

Complications

Ventriculoperitoneal shunt complications

Follow-up

Alternative Treatments


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

Postoperative Imaging After Ventriculoperitoneal Shunt for idiopathic normal pressure hydrocephalus

✅ Immediate Imaging: Non-Contrast Head CT (within 24–48 hours)

Purpose:

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.

✅ Additional Imaging

2. Abdominal X-ray / Shunt Series (if indicated)

Purpose:

3. Brain MRI (1–3 months postoperative)

Purpose:

4. Functional Imaging (if shunt malfunction suspected)

Modalities:

Purpose:

📋 Summary Table

Imaging Modality Timing Purpose
CT Head (non-contrast) Immediate (24–48 h) Confirm catheter placement, rule out bleeding
Shunt Series (X-ray) As needed Follow catheter path, rule out disconnection
MRI Brain 1–3 months postop Evaluate ventricular changes and clinical response
Functional Imaging If clinically indicated Confirm shunt patency or CSF dynamics

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

1)
Delwel EJ, de Jong DA, Dammers R, Kurt E, van den Brink W, Dirven CM. A randomized trial of high and low-pressure level settings on an adjustable ventriculoperitoneal shunt valve for idiopathic normal pressure hydrocephalus: results of the Dutch evaluation programme Strata shunt (DEPSS) trial. J Neurol Neurosurg Psychiatry. 2013 Jul;84(7):813-7. doi: 10.1136/jnnp-2012-302935. Epub 2013 Feb 13. PMID: 23408069.
2)
Shaw R, Everingham E, Mahant N, Jacobson E, Owler B. Clinical outcomes in the surgical treatment of idiopathic normal pressure hydrocephalus. J Clin Neurosci. 2016 Jul;29:81-6. doi: 10.1016/j.jocn.2015.10.044. Epub 2016 Feb 28. PMID: 26935749.