Table 2.

Summarizes imaging techniques and indications[6]

Technique	Indications
Radiographs	Instrument failure, infection, failed fusion
Fluoroscopic positioned spot views	Instrument position
Radionuclide scans/PET	Infection
Ultrasonography	Fluid collections, abscesses
CT	Instrument position, pseudo-arthrosis, infection, fragments in spinal canal, vertebral alignment
MR imaging	Infection, failed back, recurrent disc, recurrent tumor
Diagnostic injection/aspiration	Confirm source of pain, aspiration of pseudo-bursae or organisms for infection

CT: Computed tomography; MR: Magnetic resonance; PET: Positron emission tomography.