MAGNETIC RESONANCE STUDIES OF BONE MARROW HEMATOPOIESIS

拟议工作的目标是开发一种快速、定量、非 有创性估计骨髓体积分数的方法 被血细胞占据。在血液学中，这个参数被称为 “细胞百分率”，用来测量总的活跃骨髓 在各种各样的临床情况下的体积。 目前，测量细胞百分比的唯一方法是通过 针吸或活组织检查。除了给病人带来不适之外， 活组织检查和抽吸物仅限于骨骼的表面区域，例如 髂骨后缘。目前还没有直接的方法来 多个重要部位血细胞百分率的测定 生产，如脊椎。 我们最近完成了一项使用质子磁共振的初步研究 光谱学证明了非侵入性检测的可行性 测定骨髓细胞百分率。我们现在建议 建立一种基于图像的细胞百分比分析方法 利用骨髓中水分和脂肪的相对浓度以及 核弛豫时间和水的自扩散系数。 该项目的成功完成将产生一种快速的方法 评估消除相关疼痛的细胞百分比 并提供有关血细胞产生的信息 在以前无法接近的解剖位置。有了这些新技术，它 将有可能1)量化活动的扩张或收缩 因疾病或输注血细胞后的骨髓体积 生长激素，可能2)识别残留的血液区域 化疗后出现的疾病。

The goal of the proposed work is to develop a fast, quantitative, non- invasive method for estimating the fractional volume of bone marrow occupied by blood cells. In hematology, this parameter is known as the "percentage cellularity" and is used to gauge the total active bone marrow volume in a wide variety of clinical situations. Presently, the only way to measure the percentage cellularity is via a needle aspirate or biopsy. In addition to causing patient discomfort, biopsies and aspirates are limited to superficial areas of bone, such as the posterior iliac crest. There is presently no direct method for assessing the percentage cellularity at many important sites of blood cell production, such as the vertebrae. We have recently completed a pilot study using proton magnetic resonance spectroscopy which demonstrated the feasibility of non-invasively measuring the percentage cellularity in bone marrow. We now propose to develop an image based assay for the percentage cellularity which makes use of the relative concentrations of water and lipid in marrow as well as nuclear relaxation times and self-diffusion coefficients of water. The successful completion of this project would yield a fast method for assessing the percentage cellularity which eliminates the pain associated with the needle biopsy and provides information on blood cell production at previously inaccessible anatomical sites. With these new techniques it will be possible to 1) quantify expansion or contraction of the active marrow volume due to disease or after the administration of blood cell growth hormones, and possibly 2) identify areas of residual hematologic disease present after chemotherapy.