These are injections close to the nerves of the neck or lower back as they leave the spine, or into the epidural space within the spine.

The injection may help to confirm that compression or irritation of a particular nerve is responsible for your symptoms and aims to provide relief from neck, back, leg or arm pain.


You will lie on the CT table on your front. Your skin will be cleaned with antiseptic and local anaesthetic injected. The radiologist inserts a very fine needle into the location that your doctor has asked us to inject using an aseptic technique. We use a CT machine to guide the placement of the needle safely and accurately into the correct position and a small amount of X-ray contrast or air may be injected to help confirm this.

A long lasting anaesthetic (e.g. Ropivacaine) and a long acting steroid (e.g. Celestone) are usually injected together.

Risks / Side Effects

Side effects which may occur include:

  • Worsening of symptoms and weakness for 24-48 hours
  • Increased blood sugar levels in diabetics
  • Insomnia, flushing and palpitations.
  • Local bruising and soreness

Infection is an uncommon, but serious side effect.

Serious side effects causing permanent neurological damage can occur extremely rarely.

If X-ray contrast is administered there is a small risk of allergic reaction. This includes flushing, hives and difficulty breathing. Severe reactions are rare and life-threatening reaction extremely rare (1 in 170,000).

Before your Scan

It is essential that your previous x-ray, CT or MRI films are available at the time of the injection. Please bring these with you to your appointment if you have them.

No specific preparation is required. If you are on any special drugs or have diabetes and are on insulin, take your usual medicines and diet.

Please inform us if you are on medication to thin your blood (eg. Warfarin, Aspirin or Clopidogrel), have an iodine allergy or are pregnant or breastfeeding.

Your doctor may request this procedure to be performed with sedation, in which case you will be required to fast and a short stay hospital admission will be necessary.

You will require someone to collect you and take you home after the injection.

Other Information

Following the injection you may feel numbness, tingling and weakness in the leg. This will wear off after several hours.

The local anaesthetic may give pain relief initially, but will wear off after a few hours and the pain may return. It can take several days for the steroid to begin to work and may take up to 2 weeks for it to have maximum effect.

The effect of the steroid can last for a week, several months or years. Sometimes there is no pain relief from the injection.

Avoid strenuous activity for at least 48 hours after the injection.

If required, a simple analgesic such as paracetamol (Panadol) or an anti-inflammatory should be sufficient. An ice pack may also provide some relief.

Infection is a potential side effect – If you notice any fever or redness, swelling, or increased pain at the injection site after the first 2 days, notify your referring doctor or call the clinic where the injection was performed immediately.

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