Clinical Report: Partial Sensory Rhizotomy for Recurrent Therapy-Resistant Trigeminal Neuralgia

Overview

Partial sensory rhizotomy (PSR) offers a surgical option for patients with recurrent or therapy-resistant trigeminal neuralgia (TN) when microvascular decompression (MVD) is not feasible. This single-center experience highlights the surgical technique, patient selection, and outcomes of PSR in cases lacking neurovascular compression.

Background

Trigeminal neuralgia is a chronic pain syndrome characterized by severe, shock-like facial pain often triggered by innocuous stimuli. The primary cause is usually focal demyelination at the trigeminal nerve root entry zone, frequently due to vascular compression. While medical therapy is first-line, surgical options like MVD are preferred when a neurovascular conflict exists. However, recurrence after MVD or percutaneous procedures is common, and PSR is considered for refractory cases without vascular compression.

Data Highlights

The study retrospectively reviewed patients treated with PSR between 2004 and 2023 who had failed prior treatments including MVD and percutaneous procedures. Surgical exploration confirmed absence of neurovascular compression before PSR was performed. Intraoperative neuromonitoring and endoscopic inspection were used to identify and preserve motor fibers while selectively cutting sensory fibers corresponding to pain distribution. Follow-up data were collected via telephone interviews.

Key Findings

• PSR was performed only in patients without identifiable neurovascular compression on imaging and intraoperative inspection.
• Intraoperative neuromonitoring and endoscopic guidance allowed precise identification and preservation of motor fibers during rhizotomy.
• The sensory root was divided into three parts corresponding to trigeminal branches, and selective cutting was tailored to the patient’s pain distribution.
• Patients had previously undergone multiple treatments including MVD and percutaneous procedures with poor or no symptom improvement.
• PSR provided an alternative surgical option for therapy-refractory TN, especially in cases where MVD was not indicated.

Clinical Implications

PSR can be considered a viable surgical option for patients with recurrent or therapy-resistant TN lacking neurovascular compression, particularly after failure of other treatments. Careful intraoperative identification of nerve fibers is critical to minimize motor deficits. Patient counseling should emphasize the potential for sensory loss and the balance between pain relief and postoperative complications.

Conclusion

Partial sensory rhizotomy represents a targeted surgical approach for refractory trigeminal neuralgia in the absence of vascular compression, offering pain relief when other treatments have failed. Meticulous surgical technique and patient selection are essential to optimize outcomes.

References

1. Jannetta 1993 -- Microvascular decompression for trigeminal neuralgia
2. Bederson and Wilson -- Recurrence rates after MVD and PSR
3. Zakrzewska et al. -- Patient satisfaction after PSR versus MVD
4. Dandy 1929 -- Partial transection of trigeminal nerve for TN