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EPIDUROSCOPY
| Introduction |
 Epiduroscopy
Epiduroscopy was developed in the 1990's. A fibre optic camera is
inserted through the sacral hiatus into the lower epidural space,
and is then guided upwards towards the lower lumbar discs and nerve
roots.
- Epiduroscopy has two main uses:-
- Releasing epidural adhesions
where they are causing chronic sciatica. Adhesions can form
around the lower lumbar nerve roots after decompressive surgery
for disc disease, or after a bad bout of inflammatory sciatica
in the absence of surgery. Epidural adhesions can usually be
identified on an enhanced MRI scan using intravenous gadolinium.
They also cause uneven spread of x-ray contrast when performing
an epidurogram.
- Injecting mixtures of local
anaesthetic and depot steroid around inflamed nerve roots
when epidural injections / nerve root blocks have been
unsuccessful. The presence of adhesions can prevent epidurally
injected drugs from reaching the inflamed nerve roots.
- Contra-indications - epiduroscopy
is not advised in the presence of altered coagulation (warfarin,
liver or haematological disease). The elderly do not tolerate the
procedure well due to the rise in intra-cerebral pressure caused by
the saline flushing system.
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| Technique |
- The procedure
The Procedure is performed in the face-down position, under
intravenous sedation and local anaesthesia, whilst using x-ray
screening in an operating theatre to minimise infection.
- Local anaesthetic is injected in and around the sacral hiatus to
numb the area. A small needle is inserted through the sacral
(caudal) hiatus into the epidural space. Through this needle is then
passed a fine metal guide wire. The small needle is then removed
leaving the guide wire in place in the epidural space. A series of
dilators are then passed over the guide wire until the sacral
membrane will accept a sheath cannula (see diagram above). Once the
sheath is in place, the guide wire is removed.
- A steerable catheter
A steerable catheter attached to a fibreoptic epiduroscope is then
inserted through the centre of the sheath until it enters the
epidural space. Passage of the steerable catheter is enhanced by
using a saline flush system attached to a side port on the sheath.
- The fibreoptic epiduroscope is then advanced upwards using x-ray
guidance, until it reaches the area where
Epidural Adhesions
epidural adhesions have been found on an MRI scan.
- Once in the correct area, epidural adhesions can be gently
broken down using the epiduroscope tip Epiduroscope Tip.
Afterwards, local anaesthetic and depot steroid can be injected
around any inflamed nerve roots in the area.
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| Complications |
- Direct Nerve Root Injury is
possible during epiduroscopy, but is minimised by having the patient
awake and able to verbally communicate with the operator.
- Dural Tears can sometimes occur
caused by the epiduroscope making a small hole in the dural
membrane. This causes a Post Dural Puncture (Spinal) Headache, which
usually settles in a few days, but may continue to be problematic
for several weeks in a minority of cases. In the UK, spinal
headaches are treated by performing an epidural blood patch to seal
the hole.
- Macular Haemorrhages or bleeding in
the internal layers of the eye, can occur when excessive volumes of
saline flush are used during the procedure. Excessive saline causes
an acute rapid rise in intra-cerebral pressure, leading to
haemorrhage in the eyes. These can be avoided by limiting the volume
of flush used during the procedure.
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