Department of Electrical Engineering and Computer Science and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
VA Boston Healthcare System, Boston, Massachusetts, USA.
Gastrointest Endosc. 2017 Sep;86(3):476-484.e3. doi: 10.1016/j.gie.2017.01.034. Epub 2017 Feb 5.
Angiogenesis is associated with neoplastic progression of Barrett's esophagus (BE). Volumetric optical coherence tomography angiography (OCTA) visualizes subsurface microvasculature without exogenous contrast agents. We investigated the association of OCTA microvascular features with low-grade dysplasia (LGD) and high-grade dysplasia (HGD).
Fifty-two patients undergoing BE surveillance or endoscopic eradication therapies for dysplasia were imaged using volumetric OCTA and corresponding histologic diagnoses wre obtained to yield 97 data sets (nondysplastic BE [NDBE], 74; LGD, 10; HGD, 13). After evaluating OCTA image quality, 54 datasets (NDBE, 35; LGD, 8; HGD, 11) from 32 patients were used to develop a training and reading protocol. The association of abnormal vessel branching and heterogeneous vessel size with LGD/HGD and a regular honeycomb vessel pattern with NDBE were investigated.
Blinded OCTA reading of 41 OCTA datasets (NDBE, 27; LGD, 7; HGD, 7) was performed by readers with various levels of OCT/OCTA experience including 3 OCT trainees, 1 gastroenterologist, and 2 gastroenterology fellows. Among the 6 readers, OCTA features of abnormal vessel branching and heterogeneous vessel size had an overall 94% sensitivity (95% CI, 89-99) and 69% specificity (95% CI, 62-76) for differentiating LGD/HGD versus NDBE with a mean reading time of 45 seconds per data set and moderate (kappa = .58) interobserver agreement.
Volumetric en face OCTA imaging enables rapid examination of depth resolved microvascular features with near-microscopic resolution. OCTA can visualize microvascular features associated with LGD/HGD with high accuracy, which motivates new technologic advances and future studies investigating the diagnostic performance of OCTA.
血管生成与 Barrett 食管（BE）的肿瘤进展相关。容积光学相干断层扫描血管造影（OCTA）可在不使用外源性对比剂的情况下可视化皮下微血管。我们研究了 OCTA 微血管特征与低级别异型增生（LGD）和高级别异型增生（HGD）之间的关系。
对 52 例接受 BE 监测或内镜下异型增生治疗的患者进行了容积 OCTA 成像，并获得了相应的组织学诊断，共获得了 97 组数据（非异型增生 BE [NDBE] 74 例；LGD 10 例；HGD 13 例）。在评估 OCTA 图像质量后，从 32 例患者中选择了 54 组（NDBE 35 组；LGD 8 组；HGD 11 组）数据来制定培训和阅读方案。研究了异常血管分支和不均匀血管大小与 LGD/HGD 的关系，以及规则的蜂窝状血管模式与 NDBE 的关系。
由具有不同 OCT/OCTA 经验的 6 位读者对 41 组 OCTA 数据（NDBE 27 组；LGD 7 组；HGD 7 组）进行了盲法 OCTA 阅读，其中包括 3 位 OCT 学员、1 位胃肠病学家和 2 位胃肠病学研究员。在这 6 位读者中，异常血管分支和不均匀血管大小的 OCTA 特征在区分 LGD/HGD 与 NDBE 时的总体敏感性为 94%（95%CI，89-99），特异性为 69%（95%CI，62-76），平均阅读时间为每个数据集 45 秒，观察者间一致性中等（kappa=0.58）。
容积 OCTA 成像能够快速检查深度分辨的微血管特征，具有近微观分辨率。OCTA 可以以高精度可视化与 LGD/HGD 相关的微血管特征，这激发了新技术的进步和未来研究来探索 OCTA 的诊断性能。
