P033 Could this atypical image be an unexpected combination? A visual vignette

<h3>Background and Aims</h3> Transforaminal epidural steroid injections (TFESI) are commonly preferred interventional treatments for low back pain due to lumbar radiculopathy. Complications related to the procedure may take place. We report the case of a patient with a combination of intradural contrast media spread and dural pulsation during TFESI for lumbar radicular pain and aim to raise awareness of the importance of recognising and interpreting atypical images in interventional pain procedures for patient health. <h3>Methods</h3> A 67-year-old woman presented with low back and right leg pain due to spinal stenosis. We performed right L3 TFESI with a 22G 90 mm Quincke spinal needle to the area compatible with the right L3 neural foramen under the guidance of a C-arm fluoroscopy (GEMSS-Spinel 3G) device. On imaging, the needle placement was consistent with the epidural region, but the contrast spread suggested subdural spread. When we administered contrast material again (1 cc), we observed that the contrast extended and widened a little more in the cranio-caudal direction in the same region but did not disperse. Therefore, we obtained a live fluoroscopic image. The contrast media was accumulated in the same region and showed pulsatile properties in the images. We speculated that this image might be a combination of intradural spread and dural pulsation. <h3>Results</h3> We terminated the procedure since the image was atypical. The patient did not develop any neurological deficit, we obtained lumbar MRI and CT angiography to exclude other causes. The neuroradiologist at our hospital evaluated the examinations and reported no evidence of venous dilatation, arteriovenous fistula or arteriovenous malformation in the spinal region. To alleviate the persistent pain of the patient, we prescribed medical treatment. <h3>Conclusions</h3> Atypical contrast media distributions may be seen during procedures. To avoid possible complications, it is vital for physicians to have a thorough knowledge of the contrast media distribution pattern.