Mankani Mahesh H, Kuznetsov Sergei A, Avila Nilo A, Kingman Albert, Robey Pamela Gehron
Division of Plastic Surgery, Department of Surgery, University of California-San Francisco, San Francisco General Hospital, 1001 Potrero Ave, Ward 3A, San Francisco, CA 94110, USA.
Radiology. 2004 Feb;230(2):369-76. doi: 10.1148/radiol.2302011529.
To determine whether quantitative computed tomography (CT) can be used to estimate the extent of new bone formation in hydroxyapatite-tricalcium phosphate (HA-TCP)-based transplants.
Bone-forming transplants were generated by attaching cultured human bone marrow stromal cells to aliquots of HA-TCP particles and were placed in subcutaneous pockets in immunocompromised mice. After 8 weeks, the transplants were individually imaged; each scan included a phantom. Overall bone mineral density (BMD) of each transplant was obtained. Hematoxylin-eosin-stained sections of the same transplants were then examined histologically, which is the reference standard for assessing bone formation. The extent of bone in each transplant was scored on a semiquantitative scale ranging from 0 to 4 by three independent blinded observers; the bone score for each transplant was calculated by averaging the three observer scores. BMD was compared with the histologically determined bone score for each transplant. Statistical evaluations included (a) calculation of empiric receiver operating characteristic curves to determine optimum BMD thresholds and (b) determination of the relationship between BMD and bone score, including derivation of Pearson correlation coefficients.
One hundred twenty transplants were evaluated. Average BMD of 600 mg/cm3 K2HPO4 or more was noted in transplants with appreciable bone formation (bone score > or = 3), while average BMD of less than 600 mg/cm3 K2HPO4 was seen in transplants with poor bone formation (bone score < 3) (P <.001). Among transplants with appreciable bone formation, the BMD was proportional to the extent of mineralized matrix present in the new bone.
Use of quantitative CT offers a practical approach for the noninvasive determination of new bone formation in mineralizing bone marrow stromal cells and HA-TCP transplants.
确定定量计算机断层扫描（CT）是否可用于评估基于羟基磷灰石-磷酸三钙（HA-TCP）的移植物中新生骨形成的程度。
通过将培养的人骨髓基质细胞附着于HA-TCP颗粒等分试样来制备成骨移植物，并将其置于免疫受损小鼠的皮下囊袋中。8周后，对移植物进行单独成像；每次扫描均包括一个体模。获取每个移植物的整体骨矿物质密度（BMD）。然后对相同移植物的苏木精-伊红染色切片进行组织学检查，这是评估骨形成的参考标准。由三名独立的盲法观察者对每个移植物中的骨量进行0至4的半定量评分；每个移植物的骨评分通过平均三名观察者的评分来计算。将BMD与每个移植物经组织学确定的骨评分进行比较。统计评估包括：（a）计算经验性受试者操作特征曲线以确定最佳BMD阈值；（b）确定BMD与骨评分之间的关系，包括推导Pearson相关系数。
共评估了120个移植物。在骨形成明显（骨评分≥3）的移植物中，观察到平均BMD为600 mg/cm³ K₂HPO₄或更高，而在骨形成较差（骨评分<3）的移植物中，平均BMD低于600 mg/cm³ K₂HPO₄（P<.001）。在骨形成明显的移植物中，BMD与新骨中矿化基质的程度成正比。
定量CT的应用为无创测定矿化骨髓基质细胞和HA-TCP移植物中的新生骨形成提供了一种实用方法。
