Illustration of brain with missing skull piece, highlighting fluid buildup and potential risks.

Decompressive Craniectomy: Understanding Hydrocephalus Risk

Soraya Malik in Health & Wellness December 2025 • 4 min read.

"A Guide to Identifying and Managing Post-Traumatic Hydrocephalus after Skull Removal Surgery"

Decompressive craniectomy is a procedure neurosurgeons use to treat elevated pressure inside the skull when other methods aren't effective. It involves removing a portion of the skull to allow the brain to swell without being compressed. While this surgery can be life-saving, it's also associated with potential complications.

One such complication is post-traumatic hydrocephalus (PTH), a condition where there's an abnormal buildup of cerebrospinal fluid (CSF) in the brain's ventricles. This can lead to increased pressure and neurological problems. Understanding the risk factors for PTH after decompressive craniectomy is crucial for early detection and management.

This article breaks down recent research into identifying those risk factors, particularly focusing on the connection between hydrocephalus and subdural hygroma (SDG), a collection of fluid between the brain's surface and the dura mater, following decompressive craniectomy. Knowing these risks can help doctors monitor patients more closely and intervene when necessary.

Unveiling the Risks: What Increases Hydrocephalus After Craniectomy?

Illustration of brain with missing skull piece, highlighting fluid buildup and potential risks.

A recent study investigated the incidence and risk factors for post-traumatic hydrocephalus (PTH) following decompressive craniectomy (DC). The study focused on 94 patients with severe head injuries requiring DC, with a closer analysis of 41 patients who had at least four follow-up CT scans over three months. Post-traumatic hydrocephalus was identified using specific measurements on CT scans (frontal horn index) and clinical symptoms. Subdural hygroma (SDG) was defined as a low-density area greater than 5mm thick on CT scans.

The research revealed that:

Hydrocephalus developed in 29.3% of patients.
Subdural hygroma (SDG) occurred in 48.8% of patients.
A significant association was found between the development of PTH and delayed cranioplasty (skull reconstruction).
Interhemispheric SDG (SDG located between the brain hemispheres) was also significantly associated with PTH.
No significant relationship was found between PTH and factors like age, sex, initial Glasgow Coma Scale (GCS) score, or the presence of certain types of bleeding.

These findings suggest that the timing of skull reconstruction and the presence of interhemispheric SDG are important factors to consider when assessing the risk of hydrocephalus after decompressive craniectomy.

Key Takeaways: What This Means for Patients and Caregivers

This research highlights the importance of being aware of the potential for hydrocephalus to develop after decompressive craniectomy. While the surgery is often necessary to save lives and reduce brain pressure, it's crucial to monitor patients closely for signs of complications.

The study emphasizes that delayed skull reconstruction and the presence of interhemispheric subdural hygroma increase the risk of developing hydrocephalus. This knowledge can help doctors make informed decisions about the timing of cranioplasty and the need for closer monitoring in patients with interhemispheric SDG.

If you or a loved one has undergone decompressive craniectomy, it's essential to discuss these findings with your medical team. Early detection and management of hydrocephalus can significantly improve outcomes and quality of life.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.13004/kjnt.2012.8.2.110, Alternate LINK

Title: Risk Factors For The Post-Traumatic Hydrocephalus Following Decompressive Craniectomy In Severe Traumatic Injury Patients

Subject: Surgery

Journal: Korean Journal of Neurotrauma

Publisher: Korean Neurotraumatology Society

Authors: Byung-Rae Cho, Hyung-Jin Lee, Hong-Jae Lee, Jin-Seok Yi, Ji-Ho Yang, Il-Woo Lee

Published: 2012-01-01

Everything You Need To Know

What is a decompressive craniectomy, and why is it performed?

Decompressive craniectomy is a neurosurgical procedure performed to alleviate elevated pressure within the skull, typically in cases of severe traumatic brain injury. This procedure involves removing a portion of the skull to allow the brain to swell without being compressed. The significance of this surgery lies in its life-saving potential, providing a crucial intervention when other methods fail to control intracranial pressure. However, it carries inherent risks, including the potential for complications like post-traumatic hydrocephalus.

What is post-traumatic hydrocephalus (PTH), and why is it a concern following surgery?

Post-traumatic hydrocephalus (PTH) is an abnormal accumulation of cerebrospinal fluid (CSF) within the brain's ventricles, leading to increased pressure and potential neurological issues. After a decompressive craniectomy, PTH can occur because of altered CSF dynamics. The importance of understanding this condition lies in early detection and management. PTH can cause a range of symptoms and requires prompt intervention to prevent further neurological damage.

What is a subdural hygroma (SDG), and how is it related to post-traumatic hydrocephalus?

Subdural hygroma (SDG) is a collection of fluid between the brain's surface and the dura mater, often occurring after a decompressive craniectomy. Research indicates a significant association between interhemispheric SDG and the development of post-traumatic hydrocephalus. This means that when fluid accumulates in this specific location, it increases the risk of PTH. This is important because it helps doctors to monitor patients more closely and provides the insight into potentially needing an intervention.

What role does delayed cranioplasty play in the development of hydrocephalus?

Delayed cranioplasty, or skull reconstruction, is the postponement of replacing the removed portion of the skull after a decompressive craniectomy. Studies indicate a significant association between delayed cranioplasty and the development of post-traumatic hydrocephalus. This suggests that the timing of skull reconstruction is a critical factor in managing the risk of PTH. Early skull reconstruction may help to restore normal CSF dynamics and reduce the likelihood of hydrocephalus. Knowing this helps physicians to make important decisions on patient care.

What were the key findings from the research regarding hydrocephalus after decompressive craniectomy?

The study found that hydrocephalus developed in 29.3% of patients after decompressive craniectomy, and subdural hygroma occurred in 48.8% of patients. The research also identified that the timing of skull reconstruction and the presence of interhemispheric SDG are important factors to consider when assessing the risk of hydrocephalus after decompressive craniectomy. Other factors, such as age, sex, initial Glasgow Coma Scale (GCS) score, or the presence of certain types of bleeding, did not show a significant relationship with PTH.