SPET AND 3-PHASE PLANAR BONE-SCINTIGRAPHY IN ADULT PATIENTS WITH CHRONIC LOW-BACK-PAIN

Among adults, low back pain (LBP) persisting for more than 3 months is a common complaint. A variety of imaging modalities including bone sc intigraphy have been recommended as appropriate for the investigation of chronic LBP, even when there is no reason to suspect that the pain is due to tumour, infection or inflammatory arthritis. In this chronic LBP population, the diagnostic benefit of bone SPET, together with pl anar flow study, blood pool and delayed three-phase imaging, was asses sed, Altogether, 2108 consecutive adult patients were entered into the chronic LBP bone scintigraphy database. Retrospective exclusion of pa tients with a history of tumour, infection or inflammatory arthritis r educed the population to 1390, of whom 916 underwent a lumbosacral spi ne flow study and blood pool imaging in addition to planar and SPET bo ne scintigraphy. The diagnostic benefit of these imaging studies was t abulated and compared. In addition, a retrospective chart review of th e patients with renal and other soft tissue abnormalities identified b y a flow study and blood pool imaging was undertaken with a view to do cumenting any changes in treatment planning over the 6 months followin g the nuclear medicine studies. Of the lumbosacral spine abnormalities , 44.1% were seen equally well on planar and SPET images, 24.0% better on SPET, 31.4% only seen on SPET, and 0.4% only seen on planar imagin g. The distribution of abnormalities identified on SPET images in the lumbar spine was divided between vertebral bodies (36.1%), lamina or p edicles (which included frequent sites of increased uptake in the arti cular facets and pars interarticularis) (53.8%), spinous processes (8. 7%) and transverse processes (1.3%). For the flow study and blood pool imaging, there was a 16.7% rate of positive studies. However, there w ere no documented changes in treatment planning because of these posit ive findings. In conclusion, when used to examine adult patients with chronic LBP, SPET detects significantly more scintigraphic abnormaliti es than planar imaging. The addition of a flow study and blood pool im aging as part of these LBP examinations results in a significant benef it. However, the clinical utility of such flow study and blood pool im aging studies cannot be confirmed.