Microdose acquisition in adolescent leg length discrepancy using a low-dose biplane imaging system

Abstract

Background Children with leg length discrepancy often undergo repeat imaging. Therefore, every effort to reduce radiation dose is important. Using low dose preview images and noise reduction software rather than diagnostic images for length measurements might contribute to reducing dose. Purpose To compare leg length measurements performed on diagnostic images and low dose preview images both acquired using a low-dose bi-planar imaging system. Material and Methods Preview and diagnostic images from 22 patients were retrospectively collected (14 girls, 8 boys; mean age, 12.8 years; age range, 10-15 years). All images were anonymized and measured independently by two musculoskeletal radiologists. Three sets of measurements were performed on all images; the mechanical axis lines of the femur and the tibia as well as the anatomical line of the entire extremity. Statistical significance was tested with a paired t-test. Results No statistically significant difference was found between measurements performed on the preview and on the diagnostic image. The mean tibial length difference between the observers was -0.06 cm (95% confidence interval [CI], -0.12 to 0.01) and -0.08 cm (95% CI, -0.21 to 0.05), respectively; 0.10 cm (95% CI, 0.02-0.17) and 0.06 cm (95% CI, -0.02 to 0.14) for the femoral measurements and 0.12 cm (95% CI, -0.05 to 0.26) and 0.08 cm (95% CI, -0.02 to 0.19) for total leg length discrepancy. ICCs were >0.99 indicating excellent inter- and intra-rater reliability. Conclusion The data strongly imply that leg length measurements performed on preview images from a low-dose bi-planar imaging system are comparable to measurements performed on diagnostic images.

Comparison of Radiation Exposure to the Patient and Contrast Detail Resolutions Across Low Dose 2d/3d Slot Scanner and Two Conventional Digital Radiography X-Ray Imaging Systems

“…By using a computer algorithm, the system can construct three-dimensional (3D) surface images from the simultaneous two-plane images 5,6 . The MDSS is designed to lower patient doses compared with conventional digital radiography (DR) X-ray imaging systems and a few studies have shown substantial clinical potential for dose savings compared to DR and computed radiography (CR) [7][8][9][10][11][12] . The MDSS X-ray imaging system is mainly used to obtain overview images in patients with scoliosis and to measure the length of lower extremities.…”

Leg length discrepancy: A systematic review on the validity and reliability of clinical assessments and imaging diagnostics used in clinical practice

“…One study on the reliability of clinical assessments [ 27 ] had low risk of bias using the QAREL- checklist ( Table 3 ). Six studies on the validity of imaging diagnostics [ 59 – 61 , 67 , 70 , 71 ] had a low risk of bias and low concerns regarding applicability for all domains using QUADAS-2 tool ( Table 2 ). Only one study on the reliability of imaging diagnostics [ 68 ] had low risk of bias using the QAREL- checklist ( Table 4 ).…”

“…Three studies were included that used the bi-planar imaging system EOS TM for the determination of LLD [ 57 , 59 , 63 ]. In one study [ 59 ], preview images [radiation dose = 2.99 Gray x square centimeter (mGy x cm 2 )] recorded by the system were compared with diagnostic images (radiation dose = 239.26 mGy x cm 2 ). Furthermore, reliability of the methods was determined ( S2 Table ).…”

Leg Length Measurement: Review

“…Система EOS представляет собой рентгенологический аппарат, позволяющий осуществлять сьемку в двух взаимно перпендикулярных проекциях [62,63]. Был проведен ряд исследований для оценки точности измерений разновеликости нижних конечностей [64,65,66]. Ввиду высокой точности получаемых результатов эталонный метод оценки не использовался.…”