Interpretation of DXA Scans and VFA Deborah Sellmeyer, MD Director, - PowerPoint PPT Presentation

Interpretation of DXA Scans and VFA Deborah Sellmeyer, MD Director, Johns Hopkins Metabolic Bone Center Dept of Medicine, Division of Endocrinology Page 1

DXA Technology Detector (detects 2 tissue types - bone and soft tissue) Very low radiation to patient. Very little scatter radiation to technologist Patient Collimator (pinhole for pencil beam, slit for fan beam) X-ray Source (two energies with different attenuation profiles) Page 2

Lumbar Spine Positioning • Straight spine • Equal soft tissue on both sides of vertebra • Correct labeling • No artifacts Page 3

Hip Positioning Femoral shaft vertical • • Small amount lesser trochanter • Rotation decreases lesser trochanter and apparent femoral neck BMD No ischium in femoral neck ROI • Hologic Lunar Femoral Neck ROI different between Hologic and GE Lunar Page 4

DXA #1 Name, contact info for facility Name, contact info for facility Patient Name Demo- Patient Name Med Record number Med Record number graphics DOB DOB Date Software Technologist Machine Calculated = Measured BMC (g) directly area (cm2) T-score = SD’s above (+) or below (-) young reference population Z-score = SD’s above or below age matched reference population Reference population Page 5

DXA #2 Page 6

DXA #3 Page 7

DXA #4 Page 8

DXA #5 Page 9

DXA #6 Page 10

Page 11 DXA #7

Page 12 DXA #8

DXA #9 Page 13

DXA #9 Using pediatric reference, Z-score = -0.1 http://www.bcm.edu/bodycomplab/mainbodycomp.htm BONE MASS 50% during adolescence 0 10 20 30 40 50 60 70 AGE Page 14

DXA #10 Hologic Lunar Page 15

DXA #11 Hologic Lunar Page 16

2017 Page 17 DXA #12 2016

DXA #13 Page 18

DXA #13 Page 19

DXA #13 Page 20

DXA #14 Page 21

Page 22 DXA #15

2017 Page 23 2016 DXA #15

Page 24 DXA #16

Page 25 DXA #16

Page 26 DXA #17

Page 27 DXA #17

Page 28 DXA #17

Radius styloid process excluded Ultradistal line where radius and ulna meet 1/3 forearm site determine by radius length Size of ROI box ROI should extend beyond soft tissue Page 29

DXA #18 2015 Page 30 2014

Page 31 DXA #19

DXA #19 Page 32

DXA #20 Page 33

Vertebral Fracture Assessment (VFA) Page 34

Page 35

Grading Vertebral Deformities Grade 1 Sensitivity = 52%-96% Grade 2 or higher Sensitivity = 96% Specificity = 90% Page 36

Indications for VFA • Women age 65-70 years and men age 70-80 years if T-score is -1.5 or below. • Women age 70 years and men age 80 and older regardless of T-score. • Postmenopausal women and men age 50 and older with a low trauma fracture. • Postmenopausal women and men age 50-69 with: – historical height loss of 1.5 inches or more – prospective height loss of 1.5 inches or more – recent or ongoing long-term glucocorticoid treatment. F. Cosman, et. al. Osteoporos Int. 2015; 26(7): 2045–2047. Page 37

Questions? Page 38