Atenuación del artefacto metálico post cirugía de columna lumbar mediante protocolo de obtención de imagen en tomografía computarizada multicorte. Estudio de cohortes.

Laburpena

Background. In postoperative patients with metallic implants, CT scans can become less effective due to metal-related artifacts. The purpose of our study was to evaluate the effectiveness of a specific metal artifact reduction image protocol, in order to reduce the metal artifact caused by titanium pedicular screws in patients undergoing lumbar pathology by lumbar fusion. This enables surgeons to make an accurate diagnosis of the exact placement of inserted pedicle screws, making this the preferred image modality for assessing screw position after surgery.Methods. In the first part of the study, CT scans were performed on 23 patients (103 titanium alloy pedicle screws) undergoing a lumbar instrumented fusion for treatment for degenerative disease with a standard image acquisition protocol evaluating the possible overdimension caused by the artifact. In the second part, a prospective study was performed using 64-slice multidetector-row computed tomography (MDCT) on 18 patients (104 titanium alloy pedicle screws) undergoing a lumbar instrumented fusion using a specific image acquisition protocol.Results. Our results show that in the sequential CT scan group, mean overdimension (on each side) due to brightness was1.045 mm (SD 0.45). In the 64-slice multichannel CT group, mean overdimension (on each side) due to brightness was0.005 mm at the proximal part of the screw and0.025 mm at the distal part of the screw.Conclusions. The use of a specific metal artifact reduction image protocol in MDCT produces a minimal artifact following lumbar fusion with pedicle screws.