title: Radiation dose reduction in CT-guided sacroiliac joint injections to levels of pulsed fluoroscopy: a comparative study with technical considerations.
abstract: BACKGROUND
  The sacroiliac (SI) joint is frequently the primary source of low back pain. Over the past decades, a number of different SI injection techniques have been used in its diagnosis and therapy. Despite the concerns regarding exposure to radiation, image-guided injection techniques are the preferred method to achieve safe and precise intra-articular needle placement. The following study presents a comparison of radiation doses, calculated for fluoroscopy and CT-guided SI joint injections in standard and low-dose protocol and presents the technical possibility of CT-guidance with maximum radiation dose reduction to levels of fluoroscopic-guidance for a precise intra-articular injection technique.
  
  
  OBJECTIVE
  To evaluate the possibility of dose reduction in CT-guided sacroiliac joint injections to pulsed-fluoroscopy-guidance levels and to compare the doses of pulsed-fluoroscopy-, CT-guidance, and low-dose CT-guidance for intra-articular SI joint injections.
  
  
  METHODS
  Comparative study with technical considerations.
  
  
  METHODS
  A total of 30 CT-guided intra-articular SI joint injections were performed in January 2012 in a developed low-dose mode and the radiation doses were calculated. They were compared to 30 pulsed-fluoroscopy-guided SI joint injections, which were performed in the month before, and to five injections, performed in standard CT-guided biopsy mode for spinal interventions. The statistical significance was calculated with the SPSS software using the Mann-Whitney U-Test. Technical details and anatomical considerations were provided.
  
  
  RESULTS
  A significant dose reduction of average 94.01% was achieved using the low-dose protocol for CT-guided SI joint injections. The radiation dose could be approximated to pulsed-fluoroscopy- guidance levels.
  
  
  CONCLUSIONS
  Radiation dose of CT-guided SI joint injections can be decreased to levels of pulsed fluoroscopy with a precise intra-articular needle placement using the low-dose protocol. The technique is simple to perform, fast, and reproducible.
authors.affiliation: Department of Orthopaedic Surgery, University of Ulm, RKU, Germany.
authors.forename: Juraj
authors.initials: J
authors.lastname: Artner
authors.forename: Balkan
authors.initials: B
authors.lastname: Cakir
authors.forename: Heiko
authors.initials: H
authors.lastname: Reichel
authors.forename: Friederike
authors.initials: F
authors.lastname: Lattig