Three-dimensional surface scanning for registration in stereotactic neurosurgery: a cadaveric feasibility study

Area of Science:

• Neurosurgery
• Medical Imaging
• Surgical Navigation

Background:

• Stereotactic neurosurgery requires submillimetric accuracy for deep brain structure targeting.
• Current workflows use intraoperative CT, increasing radiation exposure, cost, and complexity.
• Three-dimensional surface scanning (3DSS) presents a potential radiation-free alternative for capturing craniofacial anatomy.

Purpose of the Study:

• To evaluate the feasibility of integrating 3DSS into stereotactic workflows.
• To assess the accuracy of 3DSS as a replacement for intraoperative CT.
• To determine the navigational compatibility of a 3DSS-based stereotactic approach.

Main Methods:

• A human cadaveric head underwent CT and 3DSS imaging after stereotactic frame placement.
• CT, 3DSS, and CAD models were registered using advanced point cloud alignment algorithms (FHF, RANSAC, ICP).
• Accuracy was evaluated via surface deviation, RMSE, and fiducial registration error in a neuronavigation system.

Main Results:

• 3DSS-CT fusion showed a mean surface deviation of ~0.4 mm.
• 3DSS-derived N-bar localizer alignment yielded an RMSE of 1.3 mm.
• The 3DSS workflow achieved a mean fiducial registration error of 0.14 mm, superior to the CT-based method (0.20 mm).

Conclusions:

• 3DSS enables precise, submillimetric stereotactic registration without intraoperative CT.
• This radiation-free workflow reduces operative complexity and is compatible with current navigation systems.
• Future research will focus on automation, AI integration, and clinical validation.