Pulsed Radiofrequency vs. Steroid Injections for Occipital Neuralgia
Condition: Occipital Neuralgia
MeSH terms: Neuralgia
Study type: Interventional

Summary: 
      The aim of this study is to determine whether pulsed radiofrequency or steroids are better
      for occipital neuralgia. Seventy-six patients with ON or migraine with tenderness over the
      occipital nerve who respond to occipital nerve blocks (hereafter included under the broad
      category "ON") will be randomized in a 1:1 ratio to receive either corticosteroid and local
      anesthetic injections (n=38) or local anesthetic and PRF of the occipital nerve(s) (n=38) for
      occipital neuralgia. Both patients and the treating & evaluating physicians will be blinded.
      The first follow-up visit will be at 6 weeks. Patients who obtain significant pain relief
      will remain in the study. Those patients who fail to obtain any benefit will exit the study
      and be allowed to crossover to the other treatments or receive alternative care. The second
      follow-up will be at 3 months and the final follow-up will be at 6-months post-procedure.
    

Detailed description: 
      Up to 76 patients referred to one of the participating pain clinic with occipital neuralgia,
      or migraines with occipital nerve tenderness (dual diagnoses) will be randomized in a 1:1
      ratio by a computer generated randomization table to receive one of two treatments.
      Treatments will be randomized at each institution. Within each group, those patients with
      plain occipital neuralgia, and those with occipital neuralgia with migraines, will be
      sub-randomized in the same 1:1 ratio. Diagnosis of ON will be made by low-volume (< 3 mL
      bupivacaine per nerve). Our criterion for a positive response will be > 50% pain relief
      lasting at least 3 hours. Those individuals who have symptoms in the distribution of both the
      greater and lesser occipital nerves will receive treatment of both nerves. The greater
      occipital nerve is more frequently affected than the lesser nerve.

      Half (n=38) of the patients will be allocated to receive local anesthetic & corticosteroid
      injections at each nerve (group I), with an equal number allocated to receive local
      anesthetic & PRF at each (group II). In those patients who request sedation, an intravenous
      will be inserted and light sedation administered with low doses of midazolam and fentanyl, in
      accordance with our standard clinic practice. Treatment in all patients will be accomplished
      using 20-gauge radiofrequency needles with 10 mm active tips. Prior to treating, electrical
      stimulation will be performed to ensure ample proximity to the targeted nerve(s), with our
      target threshold being concordant stimulation at < 0.3 volts at each site.

      Once proper needle position is ensured, those in group I will receive an injection at each
      nerve containing 30 mg of depomethylprednisolone mixed with 2 mL of a 50:50 mixture of 2%
      lidocaine and 0.5% bupivacaine (2.75 mL). Anywhere between 1 and 4 nerves can be injected,
      with 4 nerves being targeted if a patient had bilateral lesser and greater occipital nerve
      involvement. This will be followed by 3 cycles of sham PRF at 120 s per cycle, with slight
      (approximately 30o electrode adjustments between cycles. For sham PRF, no electrical field or
      heat is generated (i.e. the machine is not set to any radiofrequency cycle after
      stimulation), but the cycle times (120 s per cycle) are adhered to (i.e. we will wait a total
      of 6", 2" per cycle). Those patients in group II will receive injections at each nerve
      containing 2.75 mL of a solution with 2 mL of 50:50 2% lidocaine and 0.5% bupivacaine + 0.75
      mL saline (2.75 mL), followed by 3 cycles of PRF using the following standard settings:
      voltage output 40-60 V; 2 Hz frequency; 20 ms pulses in a 1-second cycle, 120 second duration
      per cycle; impedance range between 150 and 400 Ohms; and 42o C plateau temperature.

      No patient will be prescribed additional medications or therapy between their procedure and
      first follow-up. However, they will be allowed to remain on their current, stable analgesic
      regimen. Rescue medications will consist of tramadol 50 mg 1 to 2 tablets every 6 hours PRN
      (up to 8/d) and/or acetaminophen or a non-steroidal anti-inflammatory drug such as ibuprofen,
      diclofenac or ketorolac on an "as needed" basis.

      Follow-ups will be performed by a physician blinded to treatment allocation. A preliminary
      follow-up will be performed at weeks. The first full follow-up visit will be scheduled
      6-weeks from the start of treatment. A positive outcome will be defined as a > 50% decrease
      in headache coupled with a positive satisfaction rating (> 3 on a 0-5 scale). Subjects who
      obtain a positive outcome at their initial 6-week follow-up visit will remain in the study
      and return for their 3-month follow-up visit. Those with a negative outcome will exit the
      study "per protocol" to receive standard care. Subjects who obtain a positive outcome at
      1-month but experience a recurrence before their 3-month follow-up visit will also exit the
      study per protocol, with their final outcome measures recorded before they receive standard
      care. Those who obtain a positive outcome at 3-months will remain in the study for their
      final 6-month follow-up, while those who obtain a negative outcome will exit the study.
      Unblinding for both patients and the treating physician will be after the patient exits the
      study or after their final follow-up visit for those with continued benefit.
    

Intervention name(s): Pulsed radiofrequency; Corticosteroid injection; Local anethestic injection
Intervention type(s): Procedure; Drug; Drug
Intervention description(s): Local anesthetic injection and pulsed radiofrequency treatment x 6 minutes over each affected occipital nerve; Corticosteroid and local anesthetic injection plus sham pulsed radiofrequency over each affected occipital nerve
Other intervention name(s): Local anethestic injection that both arms will receive
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Occipital neuralgia; corticosteroid injection; pulsed radiofrequency