Login to Access Video or Poster Abstract: MP08-07
Sources of Funding: none

Introduction

Both patients and surgeons are exposed to ionizing radiation during endourologic procedures. Modern C-arms have settings that can be modified to lower radiation exposure, including "low-dose" and pulsed fluoroscopy. Pulsed fluoroscopy rates range from a standard rate of 30 to 1 pulse-per-second (pps). We present here the only known series evaluating the effect of 1 pps on fluoroscopy time and surgeon radiation exposure.

Methods

A retrospective review of a single endourologist's operative records was performed over a 12 month period. Adult patients undergoing ureteroscopy were included. At the 6 month point, the switch from continuous "low-dose" to 1 pps "low-dose" fluoroscopy was made. Collected data included age, gender, body mass index (BMI), aggregate stone burden, stone multiplicity, laterality, laser and ureteral access sheath usage, operative time, fluoroscopy time, rates of failed or staged ureteroscopy and complication rates. Surgeon radiation exposure was measured using 1 dosimeter placed at the torso under the lead apron and 1 dosimeter overlying the chest outside the lead apron. Deep Dose Equivalent (DDE), Lens Dose Equivalent (LDE), and Shallow Dose Equivalent (SDE) were calculated using the EDE1 formula._x000D_

Results

A total of 84 and 70 patients underwent ureteroscopy using continuous and 1 pps fluoroscopy, respectively. No significant differences were identified between the 2 groups with regards to patient age (p=0.96), sex (p=0.26), BMI (p=0.95), stone multiplicity (p=0.31), bilateral ureteroscopy (p=0.07), pre-stenting (p=0.99), staged (p=0.84) or failed ureteroscopy (p=0.99), ureteral access sheath utilization (p=0.10), or case duration (p=0.54). Patients in the 1pps cohort had a larger median stone burden (1.8cm IQR 0.9-2.8cm vs. 1.3cm IQR 0.8-2.0 cm, p=0.04). Median fluoroscopy time was reduced from 77 (IQR 54-115) to 16 seconds (IQR 13-24) using 1 pps (p<0.001). Monthly surgeon radiation exposure was reduced by an average of 64%, from 6.8±8.3 to 1.8±2.7 mRad DDE (p = 0.11), 120.6±101.4 to 49.2±66.6 mRad LDE (p=0.10), and 116.2±97.8 to 47.6±64.0 mRad SDE (p=0.11). Complications were rare without significant difference between the 2 groups. Image quality was acceptable in all cases using 1 pps fluoroscopy despite a maximal patient BMI of 82.2. The only technical compromise noted was increased motion artifact, which was easily avoided by allowing the C-arm to complete motion prior to image acquisition._x000D_

Conclusions

Use of single pulse-per-second fluoroscopy significantly reduces fluoroscopy time and lowers surgeon radiation exposure by 64%._x000D_

Funding

none