Ultrasound Guided Radiofrequency Ablation of Proximal Greater Occipital Nerve in Primary Occipital Neuralgia

In the prone position with the head slightly flexed and the US probe was placed in the neck transversely and then was located the bifid spinous process of C2 and the probe was lateralized (toward the affected side). At this level, the GON is located above the obliquus capitis inferior muscle and deeper than the semispinalis capitis muscle. The in-plane approach from medial to lateral was employed to treat the nerve with a 21 G 5-mm active tip radiofrequency needle. Sensory stimulation was administered at 50 Hz for 1 ms to induce paresthesia, pain, or irritation. A motor stimulus was applied at 2 Hz for 1 ms and up to 2 volts to see if fasciculation was absent. Then 1 mL of 2% lidocaine was administered through the RF cannulas to alleviate procedure related pain. Conventional RFA was conducted for 60 seconds at a temperature of 60 degrees. Following the procedure, 2 mg of dexamethasone was administered per lesion site.