Sphenopalatine Ganglion Pulsed Radiofrequency Treatment Outcomes

Study Design and Population This single-center, prospective study involves 55 patients diagnosed with chronic headaches and facial pain disorders, including Cluster Headache, Chronic Migraine, Trigeminal Neuralgia, and other Trigeminal Autonomic Cephalalgias (TACs). Participants are selected from patients who have been symptomatic for more than 3 months and are refractory to conventional medical treatments.

Interventional Procedure All procedures are performed in the operating room under fluoroscopic guidance, following the routine clinical practice of the Algology Department:

Positioning: Patients are placed in the supine position. A lateral fluoroscopic view of the face is obtained, ensuring the mandibular rami are superimposed.

Needle Placement: A 22-gauge, 10-cm curved radiofrequency (RF) needle with a 5-mm active tip is advanced via the infrazygomatic approach toward the pterigopalatine fossa.

Confirmation: Proper needle tip positioning is confirmed by intermittent anteroposterior (AP) imaging and sensory stimulation (50 Hz, <0.5 V), aimed at eliciting paresthesia in the maxillary nerve distribution.

Application: Once the position is verified and intravascular entry is ruled out, Pulsed Radiofrequency (PRF) is applied at 45 V with 20-ms bursts and 480-ms silent phases, maintaining a local temperature below 42°C to prevent thermal tissue damage.

Outcome Measures and Follow-up The study evaluates the efficacy and safety of the procedure over a 6-month period. Data collection is performed at baseline (pre-procedure) and post-procedure at 1 week, 1 month, 3 months, and 6 months.

The primary and secondary parameters include:

Pain Intensity: Measured using the Visual Analog Scale (VAS) and Numerical Rating Scale (NRS).

Clinical Efficacy: Assessed via the Global Perceived Effect (GPE) scale (7-point scale ranging from "very much improved" to "very much worse").

Patient Satisfaction: Measured using a 7-point Likert Scale.

Medication Consumption: Changes in analgesic and prophylactic drug use (3-point Likert scale: stopped,increased, stable, or decreased).

Safety Profile: Monitoring for any procedure-related side effects or complications during and after the PRF application.

Statistical Analysis Data will be analyzed using SPSS 25.0. Quantitative data will be tested for normality using Kolmogorov-Smirnov/Shapiro-Wilk tests. Repeated Measures ANOVA or Friedman tests will be utilized to compare longitudinal data across the five time points (baseline to 6 months).

Inclusion criteria

• Patients aged 18 years and older (no upper age limit)
• Patients diagnosed with refractory chronic headache (including cluster headache, migraine, paroxysmal hemicrania, hemicrania continua, SUNCT, or SUNA) or chronic orofacial pain / trigeminal neuralgia
• Pain duration of at least 3 months
• Pain intensity score (VAS or NRS) > 3 out of 10
• Patients unresponsive to conservative medical treatments
• Patients scheduled for sphenopalatine ganglion (SPG) pulsed radiofrequency (PRF) treatment as part of routine clinical care
• Ability and willingness to provide written informed consent

Exclusion criteria

• Systemic infection or local skin infection at the needle insertion site
• Known coagulopathy or bleeding disorders
• Presence of a cardiac pacemaker or implantable cardioverter-defibrillator (ICD)
• Presence of an intracranial mass or significant anatomical distortion in the pterygopalatine fossa region
• Previous surgical intervention involving the sphenopalatine ganglion
• Pregnancy or breastfeeding
• Severe psychiatric or cognitive disorders preventing reliable pain assessment or follow-up
• Hemodynamic instability
• Refusal to participate in the study or undergo the procedure