Zachary S Collins, Presenter: Nothing to Disclose

Minh Xuan Nguyen MD, Abstract Co-Author: Nothing to Disclose

Scott C. Bartley MD, Abstract Co-Author: Nothing to Disclose

David M. Schuster MD, Abstract Co-Author: Nothing to Disclose

Raghuveer Krishna Halkar MD, Abstract Co-Author: Nothing to Disclose

To determine if bone scanning with SPECT/CT fused imaging aids radiologists in localizing affected vertebrae in cases of compression fracture pre and postvertebroplasty.

A retrospective chart review identified 12 patients who had perioperative bone scans with SPECT/CT in cases of vertebroplasty or spinal fusion. Patients were injected with 24.5-27 mCi of 99mTc MDP. SPECT/CT was performed 2-4 hours after injection with a dual head camera with built in CT (VG/Hawkeye, GE Medical Systems Milwaukee, WI). The SPECT dataset is acquired using a LEHR collimator, 20% window at 140 keV and reconstructed with OSEM. The CT dataset is acquired on a 128 x 128 pixel matrix with tube voltage of 120 kV, current of 2.5 mA, slice width of 10mm. Two expert readers were blinded to patient history and independently analyzed non-AC SPECT only images, then AC SPECT/CT fused images.

Interpretation changed on average 62.5% of the time with the added information from SPECT/CT. For reader #1, the interpretation changed in 7/12 patients and for reader #2, in 8/12 patients. Types of changes included shifting specific level of vertebral involvement, changing precise location of involvement within a vertebra or including/excluding affected vertebrae. In one case, with the addition of SPECT/CT, both reader's independent findings of T9 vertebral body involvement changed to T10. Diagnostic CT confirmed a normal T9 vertebral body and the finding at T10 correlated with history of prior vertebral fusion. SPECT/CT localized prior vertebroplasties and aided in the diagnosis of complicated cases of postoperative back pain. In one patient, SPECT/CT localized activity to a new compression fracture immediately above a prior vertebroplasty site.We also observed no streak artifact or changes in attenuation correction where methylmethacrylate or metal rods were placed. We hypothesized this was from similar imaging energies of the SPECT and CT systems.

SPECT/CT more precisely localizes tracer abnormalities in the vertebra compared to traditional SPECT imaging. The greatest use lies in accurately examining affected vertebrae prevertebroplasty and in complicated cases of postoperative pain.

R.K.H.: GE, BRACCO: Material support for research.

Collins, Z, Nguyen, M, Bartley, S, Schuster, D, Halkar, R, Comparison of SPECT/CT Bone Scans versus Traditional SPECT Bone Scans in Perioperative Evaluation of Vertebral Compression Fractures.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4405793.html