49 year old female
Back pain
1. Which cause of failed back surgery is present:
a. peridural fibrosis
b. post laminectomy spondylolisthesis
c. pseudomeningocele
d. arachnoiditis
e. epidural adhesion (correct answer)
There is a two level laminectomy (T11 and T12) with posterior displacement of the cord. No abnormal intramedullary cord signal and no change in the caliber of the cord. No evidence of hemorrhage or fluid collection. No evidence of cord herniation. An adhesion may produce recurrent back and/or radicular pain.
2. What is the cause of this finding?
Inflammation, hemorrhage, and/or congestion involving the dura and adjacent soft tissue resulting in fibrotic or connective tissue band. Axial images in the same patient demonstrate the dark fibrotic band at the laminectomy site:
3. Name at least two differential diagnoses.
- arachnoid cyst
- cord herniation
- epidural hematoma
- epidural empyema
4. What is the treatment for this finding?
The main treatment involves the release or lysis of adhesion or "adhesinolysis". This may be performed endoscopically or non-endoscopically via a catheter injection.
Surgical techniques to attempt to prevent the formation of adhesions have included using more minimally invasive techniques, the development of drugs to reduce inflammation (eg. mitomycin C, dexamethasone, NSAIDs) and the use of an implanted barrier between the epidural space and the overlying muscles. Implanted barriers can include autologous tissue, such as fat grafts or less commonly bone graft, or a biodegradable polymeric material. Examples of the polymeric substance includes hyaluronic acid or polyethylene glycol hydrogel, may be natural or synthetic, and may be combined with drugs to improve its effect.