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PubMed This is a summary of 14 peer-reviewed journal articles Updated
Neurosurgery · Dandy-Walker Malformation

Managing Hydrocephalus and Surgical Options

At a Glance

Hydrocephalus affects about 80% of children with Dandy-Walker malformation and typically develops in the first few months of life. It is managed surgically using shunts or ETV to drain excess brain fluid. Parents must closely monitor their infant for signs of increased brain pressure.

Hydrocephalus—a condition where excess cerebrospinal fluid builds up in the brain—is a common feature of Dandy-Walker Malformation (DWM). It affects approximately 80% of children with the condition overall [1][2]. Crucially, hydrocephalus is often not present at birth; it typically develops within the first few months of life [3]. Therefore, even if your child is born without extra fluid buildup, close monitoring during early infancy is essential. Managing this fluid is a critical part of your child’s care, as it relieves pressure on the brain and supports healthy development.

Surgical Management Options

Because every child’s brain structure in DWM is unique, neurosurgeons have several ways to manage the extra fluid. The goal is to move the fluid from the brain to another part of the body (usually the abdomen) where it can be safely reabsorbed.

  • Ventriculoperitoneal (VP) Shunt: This is the most common approach. A thin tube (shunt) is placed in the brain’s ventricles (fluid-filled chambers) and runs under the skin to the abdomen [1][4].
  • Cystoperitoneal (CP) Shunt: If the large cyst in the posterior fossa (the back of the brain) is the main source of pressure, the surgeon may place the shunt directly into the cyst instead [5][1].
  • Dual Shunting (VCP): In some cases where the fluid cannot flow freely between the ventricles and the cyst, a “Y-shaped” shunt may be used to drain both areas simultaneously [1][6].
  • Endoscopic Third Ventriculostomy (ETV): This is a “shunt-free” surgery where a small hole is made in the floor of the brain’s third ventricle to allow fluid to escape. While ETV can be successful, it has a higher failure rate in DWM than in other types of hydrocephalus and is usually only an option if specific anatomical criteria are met [7][6].

Monitoring for Increased Pressure

As a parent, you are the most important observer of your child’s health. You should monitor for signs of increased intracranial pressure (ICP), which could indicate that fluid is building up or that a shunt is not working properly.

Signs in Infants:

  • Bulging Fontanelle: The “soft spot” on the top of the head may feel firm, full, or bulging [8].
  • Sunsetting Eyes: The eyes may appear to be driven downward, with the white part of the eye visible above the iris [9].
  • Irritability: Intense, inconsolable crying or extreme fussiness that is not typical for your child [8][10].
  • Projectile Vomiting: Persistent, forceful vomiting that is not related to feeding or a stomach bug [8].
  • Increased Head Size: A rapid increase in head circumference that crosses percentiles on a growth chart [11].

Empowering Advocacy

If you notice these signs, it is important to contact your pediatric neurosurgeon immediately or go to an emergency room. While shunt malfunctions are a known risk—including mechanical failure or infection—they are highly treatable [4][12].

Neurosurgeons often use a combination of physical exams and imaging to evaluate the situation. This might include a “Shunt Series” X-ray (a quick, low-radiation set of X-rays of the head, neck, and belly to check if the physical shunt tubing is intact and connected) or a “Rapid MRI” (a fast brain scan that uses no radiation to check the size of the fluid spaces in the brain) [13][14]. Trust your instincts; because you know your child best, you are often the first to notice the subtle behavioral changes that suggest a need for medical attention. Early intervention is the key to ensuring the best possible outcome for your child’s neurological health [1].

Common questions in this guide

Why do infants with Dandy-Walker malformation need to be monitored for hydrocephalus?
While hydrocephalus affects about 80% of children with DWM, it is often not present at birth. It typically develops within the first few months of life, making close monitoring essential to detect fluid buildup early before it causes damage.
What is the difference between a VP shunt and a CP shunt?
A Ventriculoperitoneal (VP) shunt drains fluid from the brain's ventricles to the abdomen. A Cystoperitoneal (CP) shunt is used when the main source of pressure is a large cyst in the back of the brain, draining fluid directly from that cyst instead.
What are the signs of increased intracranial pressure in an infant?
Warning signs include a bulging soft spot (fontanelle) on the top of the head, eyes that appear driven downward, extreme irritability, projectile vomiting, and a rapidly increasing head size. If you notice these signs, seek emergency medical care immediately.
Is Endoscopic Third Ventriculostomy (ETV) a good option for DWM?
ETV is a shunt-free surgery that creates a small hole in the brain to let fluid escape. While it can be successful, it has a higher failure rate in Dandy-Walker malformation compared to other conditions and is only an option if your child meets specific anatomical criteria.
How do doctors check if a shunt is working properly?
Neurosurgeons typically use a physical exam combined with a Shunt Series X-ray to check if the tubing is intact and connected. They may also use a Rapid MRI, which requires no radiation, to check the size of the fluid spaces in the brain.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.What are the specific risks and benefits of a ventriculoperitoneal (VP) shunt versus a cystoperitoneal (CP) shunt in this case?
  2. 2.Is my child a candidate for Endoscopic Third Ventriculostomy (ETV), and what is the success rate for this procedure in infants with DWM?
  3. 3.How frequently will my child need follow-up imaging in the first six months to monitor for hydrocephalus?
  4. 4.If my child needs a shunt evaluation in the emergency room, do you recommend a Rapid MRI over a CT scan to avoid radiation?
  5. 5.What is the exact protocol if we suspect the shunt is blocked or infected?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (14)
  1. 1

    Dandy Walker malformation with occipital encephalocele - personal series and updated literature review.

    Datta A, Vardhan MV, Srivastava C, Ojha BK

    Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery 2025; (41(1)):417 doi:10.1007/s00381-025-07061-3.

    PMID: 41396485
  2. 2

    Short- and Long-Term Outcomes of Prenatally Diagnosed Dandy-Walker Malformation, Vermian Hypoplasia, and Blake Pouch Cyst.

    Venkatesan C, Kline-Fath B, Horn PS, et al.

    Journal of child neurology 2021; (36(12)):1111-1119 doi:10.1177/08830738211049115.

    PMID: 34757866
  3. 3

    Dandy-Walker malformation and variants: clinical features and associated anomalies in 28 affected children-a single retrospective study and a review of the literature.

    Di Nora A, Costanza G, Pizzo F, et al.

    Acta neurologica Belgica 2023; (123(3)):903-909 doi:10.1007/s13760-022-02059-z.

    PMID: 36068432
  4. 4

    Relationship between the location of the ventricular catheter tip and the ventriculoperitoneal shunt malfunction.

    Dobran M, Nasi D, Mancini F, et al.

    Clinical neurology and neurosurgery 2018; (175()):50-53 doi:10.1016/j.clineuro.2018.10.006.

    PMID: 30366188
  5. 5

    Dandy-Walker malformation and syringomyelia: a rare association.

    Baro V, Manara R, Denaro L, d'Avella D

    Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery 2018; (34(7)):1401-1406 doi:10.1007/s00381-018-3773-2.

    PMID: 29532167
  6. 6

    Unveiling Dandy-Walker syndrome: A surprising twist in the tale of acute hydrocephalus and Down syndrome child.

    Fahed E, Msheik A, Yazbeck M, et al.

    eNeurologicalSci 2023; (33()):100480 doi:10.1016/j.ensci.2023.100480.

    PMID: 37928178
  7. 7

    The Management of Hydrocephalus in Midline Posterior Fossa Cystic Collections: Surgical Outcome From a Retrospective Single-Center Case Series of 54 Consecutive Pediatric Patients.

    Guida L, Benichi S, Bourgeois M, et al.

    Neurosurgery 2023; (93(3)):576-585 doi:10.1227/neu.0000000000002450.

    PMID: 36921245
  8. 8

    Symptoms of Cerebrospinal Shunt Malfunction in Young Children: A National Caregiver Survey.

    Dorner RA, Lemmon ME, Vazifedan T, et al.

    Child neurology open 2023; (10()):2329048X231153513 doi:10.1177/2329048X231153513.

    PMID: 36910597
  9. 9

    Clinical Indicators of Pediatric Shunt Malfunction: A Population-Based Study From the Nationwide Emergency Department Sample.

    Razmara A, Jackson EM

    Pediatric emergency care 2021; (37(11)):e764-e766 doi:10.1097/PEC.0000000000001862.

    PMID: 31305502
  10. 10

    Clinical and socioeconomic predictors of shunt malfunction in the pediatric emergency department.

    Lehner KR, Alawneh RJ, Lee RP, et al.

    Journal of neurosurgery. Pediatrics 2024; (34(1)):75-83 doi:10.3171/2024.1.PEDS23489.

    PMID: 38579347
  11. 11

    Predicting Failure of Ventricular Shunts in the Emergency Department: The SMaRT (Shunt Malfunction and Revision Triage) Score.

    Lehner KR, Kalluri AL, Jiang K, et al.

    The Journal of pediatrics 2026; (290()):114969 doi:10.1016/j.jpeds.2025.114969.

    PMID: 41429286
  12. 12

    Outcome Analysis of Patients of Congenital Hydrocephalus with Ventriculoperitoneal Shunt at a Tertiary Care Hospital in North India.

    Bawa M, Dash V, Mahalik S, Rao KLN

    Pediatric neurosurgery 2019; (54(4)):233-236 doi:10.1159/000501018.

    PMID: 31291639
  13. 13

    Diagnosing Cerebrospinal Fluid Shunt Failure: Systematic Review and Meta-Analysis of Noninvasive and Minimally Invasive Tests in Children and Adults.

    Koschnitzky JE, Shramuk ME, Kudlinski MV, et al.

    Neurosurgery 2026; (98(6)):1206-1220 doi:10.1227/neu.0000000000003755.

    PMID: 40990524
  14. 14

    Diagnostic modalities to determine ventriculoperitoneal shunt malfunction: A systematic review and meta-analysis.

    Jayanth A, Benabbas R, Chao J, Sinert R

    The American journal of emergency medicine 2021; (39()):180-189 doi:10.1016/j.ajem.2020.09.024.

    PMID: 33067062

This page provides educational information about hydrocephalus and surgical options for Dandy-Walker malformation. It does not replace professional medical advice. Always contact your pediatric neurosurgeon immediately if you suspect a shunt malfunction.

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