The 99mTC bone scanning

The 99mTC bone scanning

Introduction

The 99mTC bone scanning possesses a high level of sensitivity but also has low specificity associated with numerous bony pathologies that include avascular necrosis, stress fractures, tumors of the bone and bone contusion. This type of scanning is most useful in the occult pathology (Agrawal, K.et al, 2015). The uptake relating to 99mTC radiotracer happens in three stages which include perfusion stage that occurs immediately, blood pooling stage usually takes around fifteen minutes and bone uptake stage which is usually delayed and takes at least two hours.

Advantages

The Compound 99mTC MDC clears fast from the blood usually forty percent within one hour from the administration. The radionuclide associated with the scan is easily available, affordable, stable and it can be detected by the cameras (Chopra, A., & Robinson, P., 2016). After injection of the bone to be scanned, the imaging of the whole body is possible without an increment in radiation dose. Lesion localization assists in focusing attention on the radiographic alterations. The major advantages associated with this kind of scan include high sensitivity which is associated with bone pathology (Davis, K. W., 2010). The 99mTC scanning supports simultaneous imaging of the entire skeleton and is used in sports medicine.

Disadvantages

The 99mTC scanning exposes the human body to radiation; its findings mostly have low specificity. This type of bone scanning in sports medicine has prolonged time for acquisition compared to other forms of scans (Standaert, C. J., & Herring, S. A., 2007). Scanning of the bone depends on osteoplastic response and it is vital to be conscious about uptake nonthreatening lesions that look like malignant pathologies.

Sensitivity and specificity of imaging modalities

Imaging modality of X-ray is the first line for analysis and evaluation of bone injuries such as fractures or dislocations. X-ray possess rapid acquisition time and is considered to be cheap even though it offers low-quality visualizations associated with soft tissue. It also has exposure to radiation (Le Jeune, J. J. et al, 1984). Computerized tomography offers enriched evaluation and analysis of bone injury especially useful in complex injuries. It supports accurate visualization associated with the anatomy of the bone and is faster than MR. This imaging modality is lesser precise than magnetic resonance considering visualization of soft tissue and has more radiation levels expose compared to x-ray.

Magnetic resonance offer enhanced evaluation and analysis associated with tissue injuries with two essential sequences which are T1 and T2. T1 offers elaborative anatomic information where fat look like hyperintense and water give the impression of hypointense. This modality is most precise in visualizing soft tissues and pathology. Magnetic resonance has absent radiation exposure (Love, C. et al., 2003). This modality is less precise than computerized tomography; it has long processing time and costly. It is not advisable for usage for a patient with implants or support gadgets.

Ultrasound usage differs from location to be scanned and personal practice. It is advantageous in the analysis of anatomic associations together with an evaluation of tendons plus ligaments (Wright, A. A. et al., 2016). Ultrasound images can be generated in any surface, it has rapid acquisition time, and the radiation exposure is absent and is affordable. The ultrasound visualization is restricted by bone and structures that possess gas. The accuracy of images relies on the level of expertise posed by the machine operator.

Conclusion

This paper discusses the advantages and disadvantages of the 99mTC bone scanning especially in sports medicine and also highlights the sensitivity and specificity of other imaging modalities.

Reference

Agrawal, K., Marafi, F., Gnanasegaran, G., Van der Wall, H., & Fogelman, I. (2015, September). Pitfalls and limitations of radionuclide planar and hybrid bone imaging. In Seminars in Nuclear Medicine. 45(5), 347-372. doi: 10.1053/j.semnuclmed.2015.02.002.

Chopra, A., & Robinson, P. (2016). Imaging athletic groin pain. Radiologic Clinics, 54(5), 865-873. Retrieved from http://dx.doi.org/10.1016/j.rcl.2016.04.007

Davis, K. W. (2010). Imaging pediatric sports injuries: lower extremity. Radiologic Clinics, 48(6), 1213-1235. doi:10.1016/j.rcl.2010.07.004

Le Jeune, J. J., Rochcongar, P., Vazelle, F., Bernard, A. M., Herry, J. Y., & Ramée, A. (1984). Pubic pain syndrome in sportsmen: comparison of radiographic and scintigraphic findings. European Journal of Nuclear Medicine, 9(6), 250-253.

Love, C., Din, A. S., Tomas, M. B., Kalapparambath, T. P., & Palestro, C. J. (2003). Radionuclide bone imaging: an illustrative review. Radiographics, 23(2), 341-358. Retrieved from https://doi.org/10.1148/rg.232025103

Standaert, C. J., & Herring, S. A. (2007). Expert opinion and controversies in sports and musculoskeletal medicine: the diagnosis and treatment of spondylolysis in adolescent athletes. Archives of Physical Medicine and Rehabilitation, 88(4), 537-540. doi:10.1016/j.apmr.2007.01.007