Osteoporozda vertebral kemik iliği yağ içeriğini kimyasal-şift MR ile değerlendirme
Date
2010
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Uludağ Üniversitesi
Abstract
Çalışmamızın amacı, lomber vertebra kemik iliği yağ içeriğinin kimyasal şift MR görüntülemeyle saptanan kantitatif ölçümlerin, osteoporozda tanı değerini araştırmaktır.Çalışmamız kurumsal etik kurul tarafından onaylanmış ve tüm katılımcılardan aydınlatılmış onam formu alınmıştır. ?Dual x-ray absorptiometry? (DEXA) yöntemine göre değişik kemik mineral dansite (KMD) değerleri olan 56 hasta (50-65 yaş arası) prospektif olarak çalışmaya alındı. DEXA sonuçlarına göre hastalar normal, osteopenik ve osteoporotik olarak gruplandı.Kantitatif kimyasal-şift MR ölçümleri sagital kesitler üzerinden yapıldı. ROI 3. lomber vertebra korpusu üzerine ve referans olarak aldığımız havaya iki radyolog tarafından farklı zamanlarda birbirinden ayrı ve kör olarak yerleştirildi. Yağlanma miktarı ?Sinyal intensite (SI) baskılanma oranı? ve ?SI indeksi? ile hesaplandı. Kantitatif değerler, DEXA sonuçlarına göre istatistiksel olarak karşılaştırıldı. Gruplar arası karşılaştırmada ?Kruskal-Wallis? ve ?Mann-Whitney-U? testleri kullanıldı. İki radyolog tarafından yapılan ölçümlerin güvenilirliği ?intraclass correlation coefficient? ile değerlendirildi.DEXA sonuçlarına göre olguların 18'i normal, 20'si osteopenik ve 18'i osteoporotikti. Olguların ortalama yaşları normal grupta 55.9 (50-64 yaş arası), osteopenide 55.5 (50-64 yaş arası) ve osteoporozda 55.1 (50-65 yaş arası) idi. Vertebral kemik iliği yağ içeriği bakımından gruplar arasında anlamlı farklılık bulunmadı (p>0.05). ?Intraclass correlation coefficient?' e göre ölçümler güvenilirdi (0.55 ve 0.60).Sonuç olarak 50-65 yaş grubundaki kadın hastalarda, vertabral kemik iliği yağlanma miktarı, BMD'nin öngörülmesinde güvenilir bir parametre değildir.
The aim of this study was to evaluate the diagnostic value of quantitative chemical-shift MR imaging measurement of lumbar vertebral marrow fat content in osteoporosis.This study had institutional review board approval and all participants provided informed consent. Fifty-six female patients (age range from 50 to 65 years) with varying bone mineral densities (BMD) as documented with dual x-ray absorptiometry (DXA) were prospectively included in the study. According to the DXA results, the patients were grouped as normal, osteopenic and osteoporotic. The quantitative chemical-shift MRI measurements were performed on sagittal sections. ROI was drawn within the third lumbar vertebral body and air (our reference point) at different time points by two radiologists separately and in a blinded manner. Fat content was calculated through ?signal intensity (SI) suppression rate? and ?SI Index?. The quantitative values were compared statistically with those obtained from DXA examinations. Kruskal-Wallis and Mann-Whitney-U tests were used for comparisons between groups. The reliability of the measurements performed by two radiologists was evaluated with ?intraclass correlation coefficient?.Eighteen subjects with normal bone density (mean T score, 0,39 ±1,13 [standard deviation]), 20 subjects with osteopenia (mean T score, -1,79±0,38), and 18 subjects with osteoporosis (mean T score, -3±0,5) were determined according to the DXA results. The mean age was 55.9 years (range 50 to 64 years) in normal group, 55.5 years (range 50 to 64 years) in osteopenic group and 55.1 years (50 to 65 years) in osteoporotic group (p=0.872). There was no statistically significant difference between ?SI suppression ratio? and ?SI Index? of normal, osteopenic and osteoporotic vertebrae (p>0.05). According to the ?intraclass correlation coefficient?, the measurements were reliable (0.55 and 0.60).In conclusion, vertebral bone marrow fat in female patients between 50-65 years of age, is not a reliable parameter for prediction of bone mineral density.
The aim of this study was to evaluate the diagnostic value of quantitative chemical-shift MR imaging measurement of lumbar vertebral marrow fat content in osteoporosis.This study had institutional review board approval and all participants provided informed consent. Fifty-six female patients (age range from 50 to 65 years) with varying bone mineral densities (BMD) as documented with dual x-ray absorptiometry (DXA) were prospectively included in the study. According to the DXA results, the patients were grouped as normal, osteopenic and osteoporotic. The quantitative chemical-shift MRI measurements were performed on sagittal sections. ROI was drawn within the third lumbar vertebral body and air (our reference point) at different time points by two radiologists separately and in a blinded manner. Fat content was calculated through ?signal intensity (SI) suppression rate? and ?SI Index?. The quantitative values were compared statistically with those obtained from DXA examinations. Kruskal-Wallis and Mann-Whitney-U tests were used for comparisons between groups. The reliability of the measurements performed by two radiologists was evaluated with ?intraclass correlation coefficient?.Eighteen subjects with normal bone density (mean T score, 0,39 ±1,13 [standard deviation]), 20 subjects with osteopenia (mean T score, -1,79±0,38), and 18 subjects with osteoporosis (mean T score, -3±0,5) were determined according to the DXA results. The mean age was 55.9 years (range 50 to 64 years) in normal group, 55.5 years (range 50 to 64 years) in osteopenic group and 55.1 years (50 to 65 years) in osteoporotic group (p=0.872). There was no statistically significant difference between ?SI suppression ratio? and ?SI Index? of normal, osteopenic and osteoporotic vertebrae (p>0.05). According to the ?intraclass correlation coefficient?, the measurements were reliable (0.55 and 0.60).In conclusion, vertebral bone marrow fat in female patients between 50-65 years of age, is not a reliable parameter for prediction of bone mineral density.
Description
Keywords
Osteoporoz, Vertebra yağ miktarı, Kimyasal-shift MRI, Osteoporosis, Vertebral fat content, Chemical-shift MRI
Citation
Mutlu, F. Ş. (2010). Osteoporozda vertebral kemik iliği yağ içeriğini kimyasal-şift MR ile değerlendirme. Yayınlanmamış uzmanlık tezi. Uludağ Üniversitesi Tıp Fakültesi.