Assessment of chronic radiation proctopathy and radiofrequency ablation treatment follow-up with optical coherence tomography angiography: A pilot study

Figure 4 Summary of normal and abnormal microvasculature in the mucosal and submucosal layers of the rectum. A: Normal rectal mucosal microvasculature consisted of a honeycomb-like microvascular pattern corresponding to subsurface capillary network; B: Abnormal rectal mucosal microvasculature had distortions to the honeycomb-like microvascular pattern, and had ectatic and tortuous microvasculature; C: Normal rectal submucosal microvasculature consisted of arterioles and venules with homogeneous vessel diameters typically of < 200 μm, in addition to shadowing from the superficial mucosal microvasculature; D: Abnormal rectal submucosal microvasculature had arterioles and venules with heterogonous and unusually high vessel diameters (> 200 μm). Scale bars are 1 mm.