Spectroscopy to diagnose back pain
June 18, 2010
Back pain is very common among the adult (and young) population. However, it is not always easy to diagnose the source of the pain. Currently, patients with lower back pain must undergo an invasive procedure known as provocative discography to help determine where the pain comes from. A die is injected into the disk via a needle until the patient reaches his or her pain threshold. Based on the level of pain expressed by the patient, the physician forms the diagnosis.
Nocimed (a Californian-based company) is currently testing Nociscan, a software that combines an MR spectroscopy sequence and postprocessing to identify chemical biomarkers of painful disks (degenerative disk disease MR – DDD MR).
There are two metabolites associated with painful disks: lactate and proteoglycan:
- Lactic acids build up in painful disks (the same phenomenon that makes muscle hurt).
- Proteoglycan holds water in the disks. A normal disk has a high content of water and proteoglycan. However, disk degeneration involves dehydration and proteoglycan breaks down. This also prevents nerve in-growth, creating a permissive environment for innervation of nociceptors [pain reporting nerves] that has been observed in the inner nuclei of degenerative painful disks (not found in healthy disks). In general, nocireceptive nerves and acidity means pain.
This technology is not yet commercially available. A two-year study has shown very good results and no false positives, but further investigation is still necessary.
Nevertheless, this new technology represents a step forward to diagnose lower back pain in a more efficient, non-invasive manner.
For more information, refer to:
- Keshari KR, Lotz JC, Link TM, et al. Lactic acid and proteoglycans as metabolic markers for discogenic back pain. Spine. 2008;33(3):312-317. PMID: 18303465
- Carragee EJ, Don AS, Hurwitz EL, et al. 2009 ISSLS Prize Winner: Does discography cause accelerated progression of degeneration changes in the lumbar disc: a ten-year matched cohort study. Spine. 2009;34(21):2338-2345. PMID: 19755936
- O’Neill C, Kurgansky M, Kaiser J, Lau W. Accuracy of MRI for diagnosis of discogenic pain. Pain Physician. 2008;11(3):311-326. PMID: 18523502
- Serena S et al. Modified Magnetic Resonance Spectroscopy Diagnosis of Painful and Non-Painful Lumbar Intervertebral Discs :Abstract
Patients, scanning and proper breathing…
June 16, 2010
Having your patients hold their breath properly during a MR or CT scan is always a challenge, especially when your patients are infants. Mueller et al. have come up with a simple volume-monitored (VM) method for performing reproducible, motion-free full inspiratory and end expiratory chest CT examinations in children. They tested the method on
fifty-two children with cystic fibrosis (mean age 8.8 ± 2.2 years). They underwent pulmonary function tests and inspiratory and expiratory VM-CT scans (1.25-mm slices, 80–120 kVp, 16–40 mAs) according to an IRB-approved protocol. The VM-CT technique utilizes instruction from a respiratory therapist, a portable spirometer and real-time documentation of lung volume on a computer. CT image quality was evaluated for achievement of targeted lung-volume levels and for respiratory motion. Overall, 94% of scans were performed at optimal volumes without respiratory motion. This method is applicable to children older than 4 years-old.
A drawback of the method, though, is the fact that the respiratory therapist has to stay in the room while the scan is being performed, with all the risks of radiation.
For more information you can read the whole article, published online in Pediatric Radiology (May 28, 2010): Volume-monitored chest CT: a simplified method for obtaining motion-free images near full inspiratory and end expiratory lung volumes
The past SIIM has presented some of the challenges and advances in Imaging Informatics in Medicine. The increasing costs in healthcare are driving the developments of more efficient ways of dealing with imaging data.
One of the fields that have experienced a tremendous development is 3D and the thin-client software, now performing almost as well as thick-clients. Thin clients are also available on on low-end hardware such as iPads and laptops, as well as work better on networks with low bandwidth and high latency. However, the workflow isn’t yet as efficient as it should be, especially in communication with RIS and PACS.
Another huge improvement comes from structured reporting format, although not yet fully integrated with RIS and PACS.
Storage is one of the challenges of digital imaging in Medicine. Cloud computing, which employs Internet-based servers for processing, storage, and secure transmission provides simple and secure cross-enterprise communication at low costs. Being internet-based, it supports multiple platforms, remote access, etc.
Digital Radiography has also experienced a lot of development in the recent years. Flat-panel digital detectors, digital tomosynthesis and CT conebeam acquisition used in interventional radiology, are just some examples. Point-of-service DR imaging is also possible, with image acquisition, processing, and display performed bedside or in the operating room. Hanging protocols will be the key to increase efficiency.
Nevertheless, a reporting-centric workflow is not yet available. Many pieces of the puzzle are already in place, but the multimedia imaging report, which uses all available data and media to create and distribute imaging information is not there yet.
