Safety and Radiation Exposure in Low-Dose CT-Guided Glycerol Rhizotomy for Trigeminal Neuralgia
Overview
This study compares radiation exposure and safety between low-dose CT-guided and fluoroscopy-guided percutaneous rhizotomy of the Gasserian ganglion for trigeminal neuralgia. Low-dose CT guidance performed outside the operating room demonstrated effective needle placement with reduced radiation exposure to patients and no radiation to personnel.
Background
Percutaneous rhizotomy targeting the Gasserian ganglion is a recognized treatment for patients with refractory trigeminal neuralgia who are not candidates for microvascular decompression. Traditional fluoroscopy-guided cannulation of the foramen ovale relies on estimated needle trajectories and can require multiple punctures, increasing risks of complications. Alternative imaging methods, including neuronavigation and intraoperative CT, improve accuracy but may increase radiation exposure. This study evaluates a modified approach using low-dose CT guidance in a radiology suite to optimize safety and minimize radiation.
Data Highlights
Parameter
Fluoroscopy-Guided Group
CT-Guided Group
Number of Procedures
32 (24 patients)
30 (23 patients)
Patient Age Range
32-78 years
32-78 years
Radiation Dose Calculation Method
PCXMC 2.0 software
ImpactDose 2.3 software
CT Scan Voltage (kV)
Not applicable
70 kV (low-dose protocol)
Personnel Radiation Exposure
Present
None (personnel vacate room during CT scans)
Key Findings
Low-dose CT-guided cannulation of the foramen ovale was successfully performed outside the operating room using a standard CT scanner with 70 kV settings.
The CT-guided approach allowed precise needle placement confirmed by 2D and 3D reconstructions and contrast filling of Meckel’s cave.
Radiation exposure to patients was quantified using effective dose calculations, showing that low-dose CT guidance can reduce cumulative radiation compared to fluoroscopy.
Personnel were not exposed to radiation during CT-guided procedures as they vacated the room during scanning, enhancing staff safety.
The CT-guided technique avoided repeated punctures and associated risks such as facial pain, hematoma, or infection.
Both fluoroscopy and CT-guided procedures were performed by experienced neurosurgeons, ensuring procedural consistency.
Clinical Implications
Low-dose CT guidance for percutaneous glycerol rhizotomy offers improved needle placement accuracy with reduced radiation exposure to patients and eliminates radiation risk to staff. This approach can be safely performed outside the operating room, potentially increasing procedural efficiency and patient throughput. Clinicians should consider adopting low-dose CT protocols to minimize cumulative radiation in patients requiring multiple interventions.
Conclusion
Low-dose CT-guided foramen ovale cannulation is a safe and effective alternative to fluoroscopy, providing precise needle placement with lower radiation exposure and enhanced safety for both patients and personnel. This technique represents a valuable advancement in the management of trigeminal neuralgia.
References
Hartel’s Technique and Fluoroscopy Guidance References [7, 10]
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