Comparison of the Values of Bone Mineral Density Between DEXAs

Statistical analysis was performed on the patients who took bone densitometry using Lunar and Hologic equipments for 5 months from January $1^{st}$ 2010 to May $30^{st}$, 2010. Patients consisted of 50 in their 40s, 100 in 50s and 50 in 60s. In addition, the results from bone densitometry were carried out on the same subject with two equipments on the same day. In case of 200 subjects, who received the bone densitometry with two equipments, the average age was 54.5 and 54.4 years old, respectively. There was no difference. The T- score of Lunar equipment was $-1.377{\pm}1.221$ and that of Hologic equipment was $-1.806{\pm}1.123$. The T-score of Lunar equipment was measured higher than that of Hologic equipment. T-test was conducted to determine the equality of the mean of two groups with 200 patients. Since the pvalue was 0.000, the value of bone mineral density was significant in two equipments. Furthermore, the patients, who were diagnosed by Lunar, showed more 'normal' and who were diagnosed by Hologic, showed more osteoporosis, which cartegorized by WHO, such as normal, osteopenia, and osteoporosis. Thus, compared results of bone densitometry on lumbar spine L1 - L4 of four normal people with the same equipment showed that T- score of Lunar equipment was $-0.4{\pm}1.2$, and T- score of Hologic equipment was $-1.1{\pm}1.5$. It showed the higher T- score was measured in Lunar equipment as well. Therefore, the correction factor should be considered to use, since T- scores are different between two equipments.

DEXA 측정기 간 골밀도 값 비교

산부인과에서 2010년 1월 1일부터 2010년 5월 30일까지 5개월간 Lunar 장비와 Hologic 장비를 사용하여 골밀도 검사를 한 환자를 40, 50, 60대 각각 50, 100, 50명 각 200명, 400명에 대한 척추 L1-L4의 T-score값을 통계적 분석을 하였으며, 정상인 4명을 두 장비에 같은 날 골밀도 검사를 한 결과와 비교 분석을 한 결과는 다음과 같다. 두 장비로 검사한 평균 연령은 54.5세와 54.4세로 차이는 없었다. 이때 T-score는 Lunar 장비가 $-1.377{\pm}1.221$이며, Hologic 장비는 $-1.806{\pm}1.123$으로 Lunar 장비의 T-score가 높게 측정이 되었다. 두 장비 간 유의수준은 P=0.000으로 유의한 차이가 있는 것으로 나타났다. 또한 WHO의 기준에 맞추어 정상, 골감소증, 골다공증으로 분류해 본 결과 Lunar 장비로 검사한 경우 정상으로 판정된 경우가 35%로 많은 반면 Hologic 장비로 검사한 경우는 골다공증으로 판정된 경우가 28%로 많았다. 이에 정상인 4명을 동일 장비에 검사한 경우 L1-L4의 T-score 값을 비교해 본 결과 Lunar 장비에서 T-score는 $-0.4{\pm}1.192$, Hologic 장비는 $-1.1{\pm}1.030$으로 나타나 역시 Lunar 장비의 T-score 값이 높게 측정되었다. 따라서 두 측정기 간 T-score 값이 다르므로 보정인자를 시용해야 할 것으로 사료된다.