Dorsal root ganglion pulsed radiofrequency using bipolar technology in patients with lumbosacral radicular pain duration ≥ 2 years

Bipolar radiofrequency ablation for cancer pain in the trigeminal distribution

Tumours in patients with head and neck cancer (HNC) are associated with a more significant decrease in quality of life compared with the rest of patients with cancer. We present a patient with pain due to HNC successfully treated with bipolar radiofrequency ablation. A man in his 70s presented with a tumour in the left V2 and V3 region, with disabling pain, Visual Analogue Scale (VAS) score of 10/10, pain on swallowing, chewing and speaking, 3 months of evolution. The patient was evaluated in the pain management department, and the interventional treatment proposed consisted of bipolar pulsed radiofrequency, followed by bipolar thermal radiofrequency of the left V2 and V3 branches with fluoroscopic guidance to achieve better control and coverage of the affected trigeminal branches. Immediately after the procedure, the patient reported a significant improvement in pain with a 0-10 VAS; hypoesthesia in the affected V2 and V3 territory was identified, but no motor weakness. The improvement in pain was maintained for 6 months with a significant improvement in quality of life and pain, which allowed him to speak, chew and swallow without pain. Later, the patient died from complications associated with the disease. The treatment approach in these patients is both pain treatment and achieving independence by allowing better speech ability and improving eating, the above as a pillar of treatment focused on improving the patient's quality of life. This approach is a potential tool in the early stage of the disease in patients with pain due to HNC.

Pulsed Radiofrequency 2 Hz Preserves the Dorsal Root Ganglion Neuron Physiological Ca2+ Influx, Cytosolic ATP Level, Δψm, and pERK Compared to 4 Hz: An Insight on the Safety of Pulsed Radiofrequency in Pain Management

Background

Pulsed radiofrequency (PRF) is beneficial for radicular pain and is commonly administered at pulse frequencies of 2 or 4 Hz. However, its effects on healthy neurons have not yet been widely studied. This study aims to determine the effect of PRF at 2 Hz and 4 Hz on the physiology of healthy dorsal root ganglion (DRG) neurons.

Methods

An in vitro experimental study was conducted using DRG neuron cultures divided into three groups. Control cells received no treatment, one cell group received 20 ms 2 Hz PRF for 360 s, and one cell group received a 4 Hz PRF 10 ms pulse for 360 s with similar energy. Ca2+ influx, mitochondrial membrane potential (Δψm), cytosolic Adenosine triphosphate (ATP), and phosphorylated extracellular signal-regulated kinase (pERK) levels were measured. The data were analyzed using the One-Way ANOVA variance with α=5%.

Results

DRG neurons exposed to PRF 2 Hz did not experience a significant change in Ca2+ influx, whereas PRF 4 Hz caused a significant decrease in Ca2+ influx compared to the basal level. PRF at 2 Hz did not cause a change in Δψm, whereas PRF at 4 Hz caused a significant decrease in Δψm (p<0.05). Both 2 and 4 Hz PRF resulted in a significant elevation in cytosolic ATP concentration, but the 2 Hz PRF had a higher cytosolic ATP than the 4 Hz group (p<0.05). Both 2 and 4 Hz did not show a significant difference in pERK intensity with respect to the control (p>0.05), indicating that there was no significant neuron activation.

Conclusion

Both frequencies did not significantly activate DRG neurons, but with similar energy delivery, PRF 2 Hz preserved the physiological properties of healthy neurons better than PRF 4 Hz did. A 2 Hz PRF is the preferred frequency in clinical applications for neuron-targeted therapy.

The treatment of persistent spinal pain syndrome with epidural pulsed radiofrequency: improvement of the technique

Background

In Persistent Spinal Pain Syndrome (PSPS), Pulsed Radiofrequency (PRF) is a used procedure. The results of PRF in PSPS performed with an electrode placed through the sacral hiatus were reported to be successful on pain in only 32% of patients. We have tried to improve the results by applying a new system to PRF.

Methods

Ten patients were treated with PRF application through a steerable epidural catheter with a reference electrode outside the foramen. This method was named "Optimization Current Flow" (OCF). The duty cycle of PRF was 2 × 10 msec and total exposure time was 150 s. Follow up was planned for 1, 3, and 6 months. The NRS score was considered to be the primary outcome.

Results

In the first 10 patients treatment was successful (69% of the patients) at 6 months follow-up.

Conclusion

This new modality of PRF in patients with PSPS seems to be superior to procedures done with a needle. Further prospective double-blind randomized long-term studies with a significant number of patients are required to validate this technique as there is a need to improve PRF results in PSPS.