A Study about Size and Shape of Bipolar Radiofrequency Lesions / 대한마취과학회지

BACKGROUND: Present limitations to monopolar RF include the small lesion size, difficulties in targeting, and questions about the reliability.In contrast with monopolar RF, bipolar RF create larger, more predictable, and more extensive ablative lesion. This study documents the optimal spacing of two needles, temperature, and time required to produce bipolar RF lesions. METHODS: Two 20-gauge 5 mm active tip needles and 10 mm active tip needles were secured in a parallel position 6, 8, and 10 mm apart and submerged in egg white that would allow visualization of the size and shape of the lesion.RF lesions were produced at 70, 80, and 90degrees C.At each temperature, photographs were taken at 30, 60, 90, and 120 seconds. RESULTS: When the 5 mm active tips with 6 mm distance were above 60 s and with 8, 10 mm distance above 120 s, continuous strip lesions were produced.10 mm active tips with 120 s were produced too.The others had discrete unipolar lesions around each cannula.The lesion size increased with a higher temperature and time.But time was the more important factor in determining lesion size. CONCLUSIONS: A continuous strip lesion was produced even though the electrode spaced 10 mm apart.And spacing the electrode 6 mm apart with 5 mm active tip and 8 mm apart with 10 mm active tip at 90degrees C for 90 s maximize the surface area of the lesions.

Degenerative Osteoarthritis of the Hip Misconceived as a Failed Back Surgery Syndrome: A case report / 대한마취과학회지

We report the treatment experience of a patient who developed pain in the right anterior thigh and buttock 3 months later after lumbar disc surgery. He was treated as failed back surgery syndrome and had no symptom improvement. On physical examination, groin pain was elicited by Patrick's test and internal rotation of the hip. Plain radiographs of the pelvis showed calcification or osteophytes near the superior lip of the acetabulum. On magnetic resonance imaging, the lesion was identified as osteophytes and joint effusion was also noted. Under C-arm guidance, we injected corticosteroids and local anesthetics, and the patient obtained dramatic pain relief and no recurrence of symptoms.

Radiofrequency Lesion Generation of the Articular Branches of the Obturator and Femoral Nerve for Hip Joint Pain: A case report / 대한통증학회지

Percutaneous radiofrequency thermocoagulation has been applied in patients with various forms of chronic pain, such as facet joint pain, cancer pain and trigeminal neuralgia. A major portion of the hip joint is innervated by the articular branches of the femoral and obturator nerves. Radiofrequency thermocoagulation of the articular branches of the obturator and femoral nerves can be a good alternative treatment for patients with hip joint pain, especially in those where surgery is not applicable. A patient suffering hip joint pain due to metastatic cancer underwent multiple radiofrequency lesioning of the femoral and obturator nerves at 80degrees C for 120 seconds, using a Racz-Finch Kit. The patient experienced about a 50% reduction in the pain, without any numbness or other side effects.