Editor-in-Chief: Alaa Abd-Elsayed, MD, PhD
BACKGROUND: Lumbar epidural steroid injections are commonly employed for management of chronic low back pain and lumbar radiculopathy, and are rarely associated with complications such as pneumocephalus. Pneumocephalus classically occurs in the setting of unintentional dural puncture during epidural steroid injection performed with the air loss-of-resistance technique. Herein, we present an unusual case of symptomatic pneumocephalus following lumbar epidural steroid injection without clear dural puncture performed with the saline loss-of-resistance technique.
CASE REPORT: The patient is a 77-year-old woman with a past medical history of anxiety and low back pain due to degenerative disc disease and foraminal stenosis who was referred to our pain medicine clinic and underwent 5 successful, uncomplicated lumbar epidural steroid injections over the course of 2 years. During her sixth lumbar epidural injection, access to the epidural space was attempted at the L5-S1 interspace but this was not possible due to extensive bone overgrowth and osteophytes. Epidural access was obtained at L3-L4 via the saline loss-of-resistance technique, with clear epidural contrast medium flow prior to the injection of medication. The patient sat up from the procedure table and developed a severe left-frontal headache that lasted for fewer than 30 seconds; the headache recurred 2 additional times in the hour immediately following this procedure and was not accompanied by any neurologic deficits. She was referred to the emergency department for further evaluation, where noncontrast computed tomography head demonstrated pneumocephalus. She was managed conservatively with as-needed pain medications, and her headaches resolved without further intervention within one week of the procedure.
CONCLUSION: Pneumocephalus following epidural steroid injection most commonly occurs as a result of unintentional dural puncture and is much more common when the air, rather than saline, loss-of-resistance technique is employed. This case demonstrates that it is possible for a patient to develop symptomatic pneumocephalus following epidural steroid injection with the saline loss-of-resistance technique. It is prudent to consider performing epidural steroid injections with the saline loss-of-resistance technique to decrease the risk of postprocedural headache.
KEY WORDS: Lumbar epidural steroid injection, pneumocephalus, postprocedural headache