Using Nuclear Medicine Imaging to Help Back Pain
For many patients experiencing chronic low back pain, diagnosis and treatment can be a challenge. The lumbar spine contains many areas that can be a cause of back pain, and an important first step for an accurate diagnosis is a thorough history and physical examination by your health care practitioner. One potential source of back pain can be the lumbar spine facet joints. If the clinical suspicion is for this area being the problem, a nuclear medicine Bone Scan with SPECT/CT imaging may be helpful.
A nuclear medicine Bone Scan involves injecting a small amount of a radioactive substance that attaches to the bones. Images are then taken in what is called a "planar" format. For a more detailed description of this exam and its procedure, please visit the exam page.
|A "planar" bone scan image|
In patients with low back pain and a clinical suspicion that the lumbar spine facet joints are a potential cause, the addition of SPECT/CT (Single Photon Emission Computed Tomography/Computed Tomography) imaging can provide a more specific assessment of the area in question.
WHAT IS A SPECT/CT SCAN?
A SPECT/CT exam involves combining a "SPECT" scan with a "CT" scan to help localize the area of abnormal activity that may be present on the planar bone scan image. For the "SPECT" part, the nuclear medicine gamma camera rotates 360 degrees around the body and forms pictures. The system can reconstruct this into an image (Figure 1). For the "CT" portion, a low dose CT image is taken, similar to other CT imaging (Figure 2). These CT images are not the same quality as those from a classic diagnostic CT scan. In this case, they are fused electronically with the SPECT images to get the SPECT/CT image (Figure 3). The SPECT/CT images are taken near the end of the second appointment of the bone scan.
|Figure 1: Reconstructed SPECT image||Figure 2: CT image|
|Figure 3: The fused SPECT/CT image|
WHAT ARE THE ADVANTAGES OF SPECT/CT?
A SPECT/CT scan can allow the clinicians to better detect the abnormal areas of activity as well as better localize them. It can also potentially guide additional specific or targeted needle injections.
HOW DO I OBTAIN A BONE SCAN WITH SPECT/CT?
As a patient, the most important thing to do is thoroughly discuss your back pain symptoms with your health care practitioner. This will help them determine if a bone scan with SPECT/CT imaging can play a role in evaluating your back pain. Your health care practitioner can then select this exam on our General Requisition under Nuclear Medicine Imaging, or on our Image-Guided Pain Therapy Requistion under Spinal Procedures. Click here to download either requisition.
Kretzschmar, M., et al. (2011) “99m Tc-DPD-SPECT/CT predicts the outcome of imaging-guided diagnostic anaesthetic injections: A prospective cohort study,” European Journal of Radiology, 80(3): 410-415
Neill, C., et al. (2010) “Role of single photon emission computed tomography in the diagnosis of chronic low back pain,” The Spine Journal, Jan: 10 (1): 70-72
Pneumaticos, S.G., et al. (2006) “Low Back Pain: Prediction of Short-term Outcome of Facet Joint Injection with Bone Scintigraphy,” Radiology, Feb; 238 (2): 693-8