gms | German Medical Science

Objective: Dosimetric data on intraoperative radiation exposure to surgeon and patient during cement augmentation is scarce. Often only fluoroscopy times with values up to 27.7 min (vertebroplasty) are reported. Radiation-protective working methods are becoming more and more important as the annual dose limits become increasingly strict. The aim of the study is the dosimetric assessment of radiation exposure during kyphoplasty using a radiation-protective surgical technique.

Methods: The prospective study examines the intraoperative radiation exposure of surgeon and patient during kyphoplasty in thoracolumbar vertebral body fractures. Using film, eye lens and ring dosimeters, the radiation exposure of surgeon and patient is measured at different locations. The applied radiation-protective surgical technique according to the ALARA (as low as reasonably achievable) principle includes the use of radiation protection equipment and beam collimation as well as keeping distance to the radiation source and avoiding continuous fluoroscopy. Dose values are reported under consideration of lower detection limits of dosimeters.

Results: 35 patients (BMI 25.9 ± 5.2 kg/m²) underwent kyphoplasty in 40 thoracolumbar vertebral bodies (19 A1 fractures, 16 A2 fractures and 5 A3 fractures). T12 (n=8) was most frequently affected, followed by L4 (n=7) and L1 (n=6). Table 1 [Tab. 1] shows the dosimetric results of the radiation exposure of surgeon and patient.

The fluoroscopy time per kyphoplasty was 42.7 ± 17.8 sec with 32 ± 13 intraoperative single radiographs and a dose area product of 105 ± 101 cGy/cm². The duration of the operation was 35.1 ± 9.8 min (single-level procedures only). On average, 2.6 ± 0.8 ml of bone cement per vertebral body were placed on each side. Low-grade prevertebral cement leakage with no clinical relevance was observed in four patients. All patients reported reduced back pain at the first postoperative day (VAS 2.4 ± 1.6 versus 6.7 ± 1.5 preoperatively; P < 0.0001, Wilcoxon matched-pairs signed rank test).

Conclusion: The radiation exposure of surgeon and patient in kyphoplasty can be significantly reduced compared to previous data by using a radiation-protective surgical technique. Applying this technique, the current annual limits for occupational radiation exposure are not exceeded. Nevertheless, all radiation protection measures should be applied in an optimized manner, since there is no threshold dose below which ionizing radiation poses no risk.