June 2009

CT-guided Injections Relieve Back Pain

Cynthia Chin, M.D.
UCSF Precision Spine and Peripheral Nerve Center

Chronic pain is a particularly difficult condition to treat because the source of pain is often unknown. Some patients suffering from back, neck, arm, leg and hip pain spend years trying various treatments. A treatment approach in which spinal injections are placed using advanced imaging technology, the 64-slice computed tomography (CT) scanner, can benefit these patients.

Injections are typically placed using fluoroscopic guidance. The 64-slice CT scanner offers advantages compared to fluoroscopy. CT creates detailed images of nerves, muscles and bones, allowing neuroradiologists to evaluate these areas as potential sources of a patient's pain and to precisely place needles at the affected nerves. This reduces risk of additional pain and increases safety by avoiding arteries and veins.

Studies have shown that CT-guided spinal injections are an accurate and precise approach for treatment of back pain. Depending on a patient's condition, pain relief lasts from weeks to months or longer. In some cases, injections completely resolve pain, allowing patients to avoid surgery. Injections also may be used to manage a patient's pain while he or she waits for surgery or begins physical therapy. A patient's response to injections can be indicative of response to surgery, providing valuable information for both patient and physician.

Patient Selection

The 64-slice CT-guided spinal injections can be performed for patients suffering from back, neck, leg, arm and hip pain as well as peripheral nerve disorders. Pain may be due to a variety of conditions, including herniated disc, spinal stenosis, facet joint and sacroiliac joint disease, synovial cysts, Tarlov cysts, vertebral and sacral fractures due to osteoporosis or tumor and nerve entrapment syndromes, such as extraspinal sciatica, also known as piriformis entrapment.

CT guided procedures may be particularly helpful for patients who are not candidates for surgery, such as elderly patients or those with pre-existing medical conditions; those who have had extensive surgery with hardware that obscures or distorts the usual spinal anatomy; and patients with nerve entrapments and cysts that may not be amenable to injection under usual fluoroscopic guidance since soft tissue structures are not visualized with fluoroscopy.


Injections are performed on an outpatient basis and take between 20 minutes to an hour. Injections are administered by a neuroradiologist. A nurse monitors the patient in the treatment room during the entire procedure. Conscious sedation is administered for comfort. Long-acting anesthetic and steroids may be injected to help decrease nerve inflammation and resultant pain. Because CT can image soft tissue structures clearly, the risk of inadvertent injection into vessels or nerves is significantly decreased.

After the procedure is completed, patients are observed for an hour before going home, at which point they can slowly resume normal physical activities. Many patients chose conscious sedation during the procedure, though it can be performed without sedation.

UCSF Precision Spine and Peripheral Nerve Center

Our neuroradiologists have over a decade of experience performing CT-guided spinal injections. We offer the very latest CT-imaging-guided procedures to diagnose and treat back, neck, arm, leg and hip pain, and peripheral nerve disorders, including:

  • Cervical, thoracic and lumbar selective nerve blocks
  • Facet and epidural injections
  • Kyphoplasty
  • Radiofrequency ablation (RFA) of facet and sacroiliac joints
  • Sacroplasty
  • Spinal biopsy
  • Spinal tumor ablation
  • Vertebroplasty

We also offer magnetic resonance (MR) neurography, an MRI for imaging the peripheral nerves beyond the spinal canal. This technology helps diagnose nerve disease in patients who have relatively normal routine lumbar or cervical spine imaging results. MR neurograms use high resolution fat suppression sequences to detect the signal of normal and abnormal nerves.

Our neuroradiologists perform all procedures and interpret results. We work closely with referring physicians to coordinate patient care. Reports are prepared within 24 hours and can be sent with your patient on a CD, "messengered" to your office or viewed online from your office using our WEBPACS system.

The UCSF Precision Spine and Peripheral Nerve Center is located at our China Basin campus.

For more information, contact the Physician Referral Service at UCSF Medical Center:

Phone(800) 444-2559
Email referral.center@ucsfmedctr.org

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