Dual energy scanning

Routinely assess acromegaly complications, including blood pressure, glucose tolerance, fasting lipid profile, cardiac evaluations (if clinically indicated), colonoscopy, dual-energy x-ray absorptiometry (DEXA) scan (hypogonadal only), evaluation of residual pituitary function, and evaluation of sleep apnea. 

EG G Z-Scan dual-energy, dual-view X-ray system... 

Two imaging systems, dual energy X-ray absorptiometry scanning (DEXA) and magnetic resonance imaging (MRI), allow for longitudinal studies of whole body composition. DEXA measures bone mineral density and content, fat content, and lean content in anesthetized mice. Echo MRI from Echo Medical System, Houston, TX, is used to measure whole body composition parameters such as total body fat, lean mass, body fluids, and total body water in live mice without the need for anesthesia or sedation (15). The MRI technology is more rapid, less than a minute to scan one mouse, than DEXA which takes about 5 min per mouse. 

Patients can undergo a dual-energy X-ray absorptiometry (DEXA) scan to confirm the diagnosis of osteoporosis. Osteoporosis is defined as having a bone mineral density which is at least 2.5 standard deviations below the peak bone mass when measured by a DEXA scan (e.g. a T-score -2.5 SD or below). 

In women aged 75 years and older, treatment is recommended without the need for prior dual energy X-ray absorptiometry (DXA) scanning. Bisphosphonates, strontium ranelate, and raloxifene are all suitable for initiation in primary care. However both SIGN (2003) and NICE (2008) recommend that a bisphosphonate (alendronate, etidronate, risedronate, ibandronate) should be used first-line. 

Effective dose was a parameter used to assess biological risk related to radiation exposure, from dual-energy X-ray absorptiometry (DXA). Children are a worst case estimate because they absorb higher doses than adults. With the exception of the hip scans in 1- and 5-year-old children, the effective doses were below the negligible individual dose limit of 1 mrem per year (Thomas et al, 2005). 

Thomas, S.R., Kalkwarf, H.J., Buckley, D.D., Heuhi, J.E. (2005). Effective dose of dual-energy X-ray absorptiometry scans in children as a function of age. J. Clin. Densitom. 8 415-22. 

Call for CT scan to be done postthrombolysis en route to Neuro ICU. Repeat CT 24 h later or at any point if clinical deterioration. Dual-energy head CT or brain MRI with gradient-echo may be helpful in differentiating contrast staining/extravasation from true ICH. 

Fiirstenberg A, Buscombe J, Davenport A. Overestimation of lumbar spine calcium with dual energy X-ray absorptiometry scanning due to the prescription of lanthanum carbonate in patients with chronic kidney disease. Am J Nephrol 2010 32(5) 425-31. 

Goldberg HI, Cann CE, Moss AA, Ohto M, Brito A, Federle M (1982) Noninvasive quantitation of liver iron in dogs with hemochromatosis using dual-energy CT scanning. Invest Radiol 17 375-380... 

Keicz F, Joseph PM, Hilal SK (1979) Noise considerations in dual energy CT scanning. Med Phys 6 418-425... 

---