Patient-Specific Ventricular Puncture Trajectory Plane and Puncture Trajectory: A Novel Method of Frontal Ventricular Puncture

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Patient-Specific Ventricular Puncture Trajectory Plane and Puncture Trajectory: A Novel Method of Frontal Ventricular Puncture

Ventricular puncture is a life-saving neurosurgical procedure—used to drain excess fluid from the brain’s ventricles—but it’s surprisingly risky. Studies show freehand attempts (relying only on scalp landmarks) fail in up to 43% of traumatic brain injury cases, and 16% of patients develop bleeding complications from the procedure. The root of the problem? Standard CT scans (axial, coronal, sagittal) don’t show the exact path a surgeon’s catheter will take. Surgeons must use spatial imagination to guess the right angle and depth—and that guesswork can lead to missed targets, repeated pokes (which damage brain tissue), or even life-threatening bleeding.

But a team of researchers from Fujian Medical University in China has developed a new way to make ventricular puncture safer and more accurate. Their method uses CT technology to create personalized “trajectory planes”—custom maps of the exact path a catheter should take for each patient—before surgery even begins.

The Problem with Freehand Puncture

Freehand ventricular puncture works for some patients, especially those with clearly enlarged, unshifted ventricles. But for people with deformed, shifted, or small ventricles (or no enlargement at all), the success rate drops sharply. Why? Every brain is unique. A “one-size-fits-all” puncture site (like the classic Kocher point) doesn’t account for individual anatomy. Worse, the actual puncture path rarely lines up with the standard CT planes surgeons use. So when designing the path, they’re essentially drawing a line in 3D space without a clear map—that’s where mistakes happen.

The Study’s Solution: Personalized CT Trajectory Planes

The researchers’ fix is elegant: they use CT multi-planar reconstruction (MPR) to rotate images around a stable anatomical reference—the line connecting the bilateral external auditory canals (the openings to the ears). This rotation creates 180 separate images (each just 1 degree apart) that cover every possible puncture path aiming at that line. For the first time, surgeons can see the exact plane where the puncture path meets the target (like the interventricular foramen, a key opening in the ventricles). They can pick the safest, most direct route for each patient—no guesswork required.

Tools to Bring the Plan to Surgery

To turn this pre-op plan into action, the team designed two simple tools:

  1. H-type guiding frame: This metal frame attaches to the patient’s head and uses a groove to hold the catheter exactly along the planned trajectory during surgery. It eliminates hand tremors or angle shifts.
  2. iPhone app and cover: The VirLaser Level app (iOS) measures the phone’s vertical (green number on the right) and horizontal (bottom right) angles. A custom cover holds the ventricular catheter in place, so the app’s angles guide the surgeon to the correct direction—like a digital compass for the brain.

Why This Method Stands Out

Existing tools to improve puncture accuracy—like real-time ultrasound or stereotactic navigation—require extra equipment, longer surgery times, or specialized training. This new method uses the pre-operative CT scan every patient already gets. A radiologist can reconstruct the trajectory planes in minutes, and surgeons use the guiding tools to follow the plan exactly. It’s personalized, fast, and doesn’t add to the cost or complexity of surgery.

The Science Behind It

The core idea is “visualizing the invisible.” By reconstructing the plane that includes both the target (e.g., the interventricular foramen) and the puncture path, surgeons can see exactly where the catheter will go before making an incision. This builds on a previous innovation from the same team, which used similar plane reconstruction to implant curved leads for deep brain stimulation (targeting two brain areas at once). Now, they’re applying that logic to ventricular puncture—with the same goal: precision.

What This Means for Patients and Surgeons

For patients, this could mean fewer failed attempts, less brain damage, and lower risk of bleeding. For surgeons, it’s a way to move beyond “feel” and “experience” to a data-driven, personalized approach—especially for tricky cases where freehand puncture is likely to fail.

The method also addresses a critical gap: most puncture paths don’t align with standard CT planes. By rotating images around the external auditory canals (a fixed reference), the team ensures the trajectory plane is always tailored to the patient’s anatomy—not a generic template.

Next Steps: Clinical Testing Needed

The researchers emphasize this is a theoretical method—they’ve shown it works in CT reconstructions, but it needs clinical testing to prove it improves real-world outcomes. They want to see if the guiding frame and app actually reduce failure rates in surgery, and if the personalized trajectories lead to fewer complications.

But the early signs are promising. The method solves one of the biggest flaws in freehand puncture: the lack of a clear, patient-specific map. If trials confirm its value, it could become a standard tool in neurosurgery—helping more surgeons hit their target on the first try.

Author and Study Details

The study was led by Chen-Yu Ding and Jun-Yu Lin (who contributed equally) from the Department of Neurosurgery at The First Affiliated Hospital of Fujian Medical University. Co-authors include Yue Chen, Yue Pang, Xiao-Yong Chen, Wen-Hua Fang, Fang-Yu Wang, Yuang-Xiang Lin, and corresponding author De-Zhi Kang (from the hospital’s Neurosurgery Research Institute and Fujian Provincial Key Laboratory of Precision Medicine for Cancer).

The research was funded by the National Natural Science Foundation of China (grant No. 81901395) and published in the Chinese Medical Journal in 2021.

References

  1. Raabe C, Fichtner J, Beck J, Gralla J, Raabe A. Revisiting the rules for freehand ventriculostomy: a virtual reality analysis. Journal of Neurosurgery. 2017;128:1–8.
  2. Kim D, Son W, Park J. Guiding protractor for accurate freehand placement of ventricular catheter in ventriculoperitoneal shunting. Acta Neurochirurgica (Wien). 2015;157:699–702.
  3. AlAzri A, Mok K, Chankowsky J, Mullah M, Marcoux J. Placement accuracy of external ventricular drain when comparing freehand insertion to neuronavigation guidance in severe traumatic brain injury. Acta Neurochirurgica (Wien). 2017;159:1399–1411.
  4. Wilson TJ, Stetler WR Jr, Al-Holou WN, Sullivan SE. Comparison of the accuracy of ventricular catheter placement using freehand placement, ultrasonic guidance, and stereotactic neuronavigation. Journal of Neurosurgery. 2013;119:66–70.
  5. Ding CY, Yu LH, Lin YX, Chen F, Wang WX, Lin ZY, et al. A novel stereotaxic system for implanting a curved lead to two intracranial targets with high accuracy. Journal of Neuroscience Methods. 2017;291:190–197.

doi.org/10.1097/CM9.0000000000001696

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