Hongyan Zhou1,2, Huihui Jia3, Gege Lei4, Tianli Zhou1,2, Jizhi Wu3, Yan Chang2, Lei Wang5, Mao Sheng6, Xiaodong Yang7,8. 1. School of Medical Imaging, Xuzhou Medical University, Xuzhou, 221004, China. 2. Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, 215163, China. 3. Department of Radiology, Children's Hospital of Soochow University, Suzhou, 215025, China. 4. School of Electronic Engineering and Optoelectronic Technology, Nanjing University of Science and Technology, Nanjing, 210094, China. 5. School of Ophthalmology and Optometry, Eye Hospital of Wenzhou Medical University, Wenzhou, 325027, China. 6. Department of Radiology, Children's Hospital of Soochow University, Suzhou, 215025, China. shengmaosuzhou@163.com. 7. School of Medical Imaging, Xuzhou Medical University, Xuzhou, 221004, China. xiaodong.yang@sibet.ac.cn. 8. Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, 215163, China. xiaodong.yang@sibet.ac.cn.
Abstract
OBJECTIVE: To investigate the variation in T2 at different zones of normal hip cartilage in children and the relationship between T2 value and age. MATERIALS AND METHODS: Nineteen children with 30 normal hip joints were evaluated with a coronal T2 mapping sequence at a 3-Tesla MRI system. The femoral cartilage and acetabular cartilage were firstly segmented by mask-based interactive method and then equally divided into eight and six radial sections, respectively. Moreover, each radial section was further divided into two layers referring to the superficial and deep halves of the corresponding cartilage. Cartilage T2 of these sections and layers were measured and subsequently analyzed. RESULTS: There was a negative correlation between the T2 values in the hip cartilage and the age of children (rs < - 0.6, P1 < 0.05). Articular cartilage T2 increased at angles close to the magic angle (54.7°). Femoral cartilage and acetabular cartilage had a relatively shorter T2 in the radial sections near the vertex of the femoral head. The T2 values in superficial layers of both cartilages were significantly higher than those in deep layers (P < 0.05). CONCLUSION: The T2 value decreases as the cartilage developing into a more mature state. Cartilage T2 values in the weight-bearing areas are relatively low due to an increase of collagen density and the loss of interstitial water. The restriction of the water molecules by solid components in the deeper layer of cartilage may decrease the T2 values.
OBJECTIVE: To investigate the variation in T2 at different zones of normal hip cartilage in children and the relationship between T2 value and age. MATERIALS AND METHODS: Nineteen children with 30 normal hip joints were evaluated with a coronal T2 mapping sequence at a 3-Tesla MRI system. The femoral cartilage and acetabular cartilage were firstly segmented by mask-based interactive method and then equally divided into eight and six radial sections, respectively. Moreover, each radial section was further divided into two layers referring to the superficial and deep halves of the corresponding cartilage. Cartilage T2 of these sections and layers were measured and subsequently analyzed. RESULTS: There was a negative correlation between the T2 values in the hip cartilage and the age of children (rs < - 0.6, P1 < 0.05). Articular cartilage T2 increased at angles close to the magic angle (54.7°). Femoral cartilage and acetabular cartilage had a relatively shorter T2 in the radial sections near the vertex of the femoral head. The T2 values in superficial layers of both cartilages were significantly higher than those in deep layers (P < 0.05). CONCLUSION: The T2 value decreases as the cartilage developing into a more mature state. Cartilage T2 values in the weight-bearing areas are relatively low due to an increase of collagen density and the loss of interstitial water. The restriction of the water molecules by solid components in the deeper layer of cartilage may decrease the T2 values.
Authors: Joost Verschueren; Duncan E Meuffels; Esther E Bron; Stefan Klein; Gert-Jan Kleinrensink; Jan A N Verhaar; Sita M A Bierma-Zeinstra; Gabriel P Krestin; Piotr A Wielopolski; Max Reijman; Edwin H G Oei Journal: J Orthop Res Date: 2017-10-09 Impact factor: 3.494