Ansari Mohammad Ali, Erfanzadeh Mohsen, Alikhani Saeid, Mohajerani Ezeddin
Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran.
Appl Opt. 2013 Apr 20;52(12):2739-49. doi: 10.1364/AO.52.002739.
Diffuse optical tomography (DOT) is an emerging oncological imaging modality that is based on a near-infrared optical technique. DOT provides the spatial volume and depth of tumors by determination of optical properties of biological tissues, such as the absorption and scattering coefficients. During a DOT, the optical fibers are kept in contact with biological tissues that introduce a certain amount of pressure on the local biological tissue. Due to this pressure, the shape of the organ, for instance a breast, deforms. Moreover, this pressure could influence the intrinsic characteristics of the biological tissue. Therefore, pressure can be an important parameter in DOT. In this paper, the effects of pressure on the determination of the size and position of a tumor in biological phantoms are studied. To do so, tissue-like phantoms that are made of intralipid, Indian ink, and agar are constructed. Defects with optical properties similar to those of tumors are placed inside the phantoms. Then various values of pressure are applied to the phantoms. Subsequently, the optical properties of phantoms as well as the position and size of the tumor are reconstructed by inverse models based on the boundary integral method. The variations of reconstructed data induced by pressure are studied. The results demonstrate that pressure causes an increase in the scattering coefficient.
扩散光学断层扫描（DOT）是一种基于近红外光学技术的新兴肿瘤成像方式。DOT通过测定生物组织的光学特性，如吸收系数和散射系数，来提供肿瘤的空间体积和深度。在进行DOT时，光纤与生物组织保持接触，这会对局部生物组织施加一定量的压力。由于这种压力，器官（如乳房）的形状会发生变形。此外，这种压力可能会影响生物组织的固有特性。因此，压力可能是DOT中的一个重要参数。本文研究了压力对生物仿体中肿瘤大小和位置测定的影响。为此，构建了由脂质、印度墨水和琼脂制成的类组织仿体。将具有与肿瘤相似光学特性的缺陷置于仿体内。然后对仿体施加不同的压力值。随后，基于边界积分法的反演模型重建仿体的光学特性以及肿瘤的位置和大小。研究了压力引起的重建数据变化。结果表明，压力会导致散射系数增加。
