Radiation reduction in computer-assisted spinal deformity surgery using 3D and 2D pediatric specific low-dose fluoroscopy protocols.

BACKGROUND

Computer-assisted navigation (CAN) facilitates accurate pedicle screw insertion in the surgical correction of adolescent idiopathic scoliosis (AIS), but exposes patients to ionizing radiation via 3D cone-beam CT and 2D fluoroscopy. The aim of this study was to evaluate pediatric-specific low-dose 3D and 2D imaging protocols, assessing their effect on radiation reduction and imaging quality.

METHODS

Thirty AIS patients were prospectively enrolled: 10 in the standard 3D protocol and 20 in the low-dose 3D protocol. Standard- and low-dose 2D fluoroscopy was used throughout, independently from 3D dose. Outcome measures included intraoperative radiation dose expressed as dose-area product (DAP), objective image quality (signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR)), and subjective image quality scoring.

RESULTS

The median 3D radiation dose was significantly lower for the low-dose protocol compared to the standard protocol (24.6 vs. 57.7 cGy*cm2, p<.001), without significant differences in SNR or CNR. Both protocols were deemed adequate for pedicle screw navigation in the subjective scoring of image quality. For 2D fluoroscopy, mean total DAP ranged from 18.5 to 106.7 cGy*cm2 with the standard protocol and from 15.9 to 61.3 cGy*cm2 with the low-dose protocol, depending on frame rate.

CONCLUSIONS

The low-dose 3D protocol achieved a radiation reduction of 57%. Despite minor, nonsignificant reductions in SNR and CNR, subjective image quality remained adequate. This supports clinical adoption of the low-dose 3D protocol, offering substantial radiation savings. 2D fluoroscopy also contributed substantially to total intraoperative dose. 2D dose may be reduced by intraoperative measures such as minimizing frame rate.