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What is Gold standard for diagnosis of osteoporosis- and explain in detail?
*Gold standard for diagnosis of osteoporosis is DEXA scan. DEXA SCAN * Commercially introduced in 1987. * Principle - 2 x ray of 70Kv and 140kv are fired on site of measurement with lag time of 4ms. * Detector detects accentuation of 2 beams. * Data is fed into computer powered with complex algorithm and calculates BMD. * SITES- * Central dexa- lumbar spine, hip, whole body. * Peripheral dexa- forearm , calcaneum. * CONTRAINDICATIONS- * PREGNANCY. * RECENT ADMINISTRATION OF CONTRAST. AGENT,NUCLEAR MEDICINE SCAN. * RADIOPAQUE IMPLANT IN MEASUREMENT AREA. * MARKED OBESITY ref : maheswari 9th ed