Injectate volumes needed to reach specific landmarks in s1 transforaminal epidural injections.
Pain Med. 2012 Oct;13(10):1265-74
Authors: Furman MB, Butler SP, Kim RE, Mehta AR, Simon JI, Patel R, Lee TS, Reeves RS
OBJECTIVES: ? We identify the contrast volumes needed to reach specific landmarks during S1 transforaminal epidural injections (S1-TFEIs).
DESIGN: ? Prospective, nonrandomized, observational human study. Setting.? Academic/private pain management practice. Subjects.? Forty-two patients undergoing S1-TFEIs were investigated. Thirty-seven patients were included in this study. Interventions.? S1-TFEIs were performed using contrast-enhanced fluoroscopic visualization.
MAIN OUTCOME MEASUREMENTS: ? After confirming appropriate spinal needle position, up to 5?mL of nonionic contrast was slowly injected. Under biplanar fluoroscopic guidance, contrast volumes were recorded as flow reached specific anatomic landmarks: the ipsilateral S1 pedicle, the superior aspect of the L5-S1 disc space, and across the midline of the spinous process.
RESULTS: ? After injecting 2?mL of contrast, 100% of S1-TFEIs spread to the medial aspect of the ipsilateral superior pedicle of S1. After injecting 3.0?mL of contrast, 92% of S1-TFEIs spread to the superior aspect of the L5-S1 intervertebral disc. After injecting 4?mL of contrast, 27% of S1-TFEIs spread beyond the midline of the spinous process, but by only a few millimeters.
CONCLUSIONS: ? This study demonstrates injectate volumes needed to reach specific anatomic landmarks in S1-TFEIs. A volume of 3.0?mL of contrast reaches the superior aspect of the L5-S1 intervertebral disc 92% of the time.
PMID: 22925558 [PubMed – in process]