Radiation exposure with hybrid image-guidance-based minimally invasive transforaminal lumbar interbody fusion.

The transforaminal lumbar interbody fusion (TLIF) is used for the treatment of back and leg pain secondary to spinal stenosis, degenerative disc disease, and spondylolisthesis. Minimally invasive surgery (MIS) is associated with less estimated blood loss (EBL), decreased length of stay, lower infection rates, and similar outcomes compared to the traditional TLIF. Fluoroscopy time has been reported with MIS-TLIF, but there are limited data on specific radiation dosages. We performed a retrospective analysis of a prospectively acquired cohort of patients undergoing MIS-TLIF. A total of 50 patients were included. Mean age was 53 years with 60% women and mean BMI of 30 (range 21-41). Diagnoses were as follows: 45 stenosis (90%), 29 spondylolisthesis (58%), 5 facet cysts (10%), 3 scoliosis (6%), and 1 cauda equina syndrome (2%). A single level was fused in 33 cases (66%), two levels in 15 (30%), three levels in 2 (4%). Average cage height was 10 mm with mean EBL of 80 ml and operative time of 240 min. The average radiation doses from intraoperative CT scan and fluoroscopy were 35.3 and 26.5 mGy, respectively. Average CT scan and fluoroscopy times were 5.2 and 37.1 s, respectively, for a total of 42.2 s. Average length of stay was 3 days (range 1-7 days). Although these data represent a preliminary experience, by streamlining the timing of intraoperative CT scan and minimizing the amount of intraoperative fluoroscopy, this protocol has the potential for decreasing operative time and radiation exposure.