Significance: To advance our understanding of the contrast observed when imaging with polarization-sensitive optical coherence tomography (PS-OCT) and its correlation with oral cancerous pathologies, a detailed comparison with histology provided via ex vivo fixed tissue is required. The effects of tissue fixation, however, on such polarization-based contrast have not yet been investigated. Aim: A study was performed to assess the impact of tissue fixation on depth-resolved (i.e., local) birefringence measured with PS-OCT. Approach: A PS-OCT system based on depth-encoded polarization multiplexing and polarization-diverse detection was used to measure the Jones matrix of a sample. A wide variety of ex vivo samples were measured freshly after excision and 24 h after fixation, consistent with standard pathology. Some samples were also measured 48 h after fixation. Results: The tissue fixation does not diminish the birefringence contrast. Statistically significant changes were observed in 11 out of 12 samples; these changes represented an increase in contrast, overall, by 11% on average. Conclusions: We conclude that the fixed samples are suitable for studies seeking a deeper understanding of birefringence contrast in oral tissue pathology. The enhancement of contrast removes the need to image immediately postexcision and will facilitate future investigations with PS-OCT and other advanced polarization-sensitive microscopy methods, such as mapping of the local optic axis with PS-OCT and PS-optical coherence microscopy.

中文翻译：

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组织固定对口腔组织样品深度分辨双折射的影响。

意义：为了增进我们对使用偏振敏感光学相干断层扫描 (PS-OCT) 成像时观察到的对比度及其与口腔癌病理的相关性的理解，需要与通过体外固定组织提供的组织学进行详细比较。然而，尚未研究组织固定对这种基于偏振的对比度的影响。目的：进行了一项研究，以评估组织固定对用 PS-OCT 测量的深度分辨（即局部）双折射的影响。方法：使用基于深度编码偏振复用和偏振分集检测的 PS-OCT 系统来测量样本的琼斯矩阵。在切除后和固定后 24 小时新鲜测量各种离体样品，与标准病理学一致。一些样品也在固定后 48 小时进行了测量。结果：组织固定不会减少双折射对比度。在 12 个样本中的 11 个中观察到了统计学上的显着变化；这些变化代表对比度总体上平均增加了 11%。结论：我们得出结论，固定样本适用于寻求更深入了解口腔组织病理学中的双折射对比的研究。对比度的增强消除了在切除后立即成像的需要，并将促进 PS-OCT 和其他先进的偏振敏感显微镜方法的未来研究，例如用 PS-OCT 和 PS 光学相干显微镜映射局部光轴。在 12 个样本中的 11 个中观察到了统计学上的显着变化；这些变化代表对比度总体上平均增加了 11%。结论：我们得出结论，固定样本适用于寻求更深入了解口腔组织病理学中的双折射对比的研究。对比度的增强消除了在切除后立即成像的需要，并将促进 PS-OCT 和其他先进的偏振敏感显微镜方法的未来研究，例如用 PS-OCT 和 PS 光学相干显微镜映射局部光轴。在 12 个样本中的 11 个中观察到了统计学上的显着变化；这些变化代表对比度总体上平均增加了 11%。结论：我们得出结论，固定样本适用于寻求更深入了解口腔组织病理学中的双折射对比的研究。对比度的增强消除了在切除后立即成像的需要，并将促进 PS-OCT 和其他先进的偏振敏感显微镜方法的未来研究，例如用 PS-OCT 和 PS 光学相干显微镜映射局部光轴。