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Aqueous humor, after draining through the trabecular meshwork, must pass through a complex network of intrascleral vessels that channel flow from Schlemm's canal to the episcleral veins. By controlling aqueous drainage, intrascleral vessels may affect IOP, contribute to ocular hypertension, and provide a potential target for hypotensive therapy. To improve visualization of these vessels, Kagemann et al. (522) used spectral-domain optical coherence tomography (SD-OCT) to obtain cross-sectional images through the conventional outflow pathway, and they applied image reconstruction techniques to generate three-dimensional renderings or 'virtual castings' of the intrascleral vessel network. For validation, the authors applied their techniques to enucleated cadaveric human eyes that were maintained at pressure by intra-cameral perfusion, and they demonstrated that the vessel architecture visualized by SD-OCT was consistent with the same structures seen by standard histology. In an impressive demonstration of the virtual casting technique, Kagemann et al. generated a full 3D reconstruction of the episcleral and intrascleral venous plexus around the 360-degree circumference of an enucleated human eye. If these techniques could be made compatible with patients' eyes, then these methods may find clinical use for assessing the outflow function of intrascleral vessels or for guiding the placement of shunts or surgical procedures. As recognized by the authors, several technical challenges remain before clinical implementation, including improving OCT scan speed so that it is compatible with patient eye movement and increasing OCT penetration depth to better resolve Schlemm's canal and collector channels/aqueous veins. Nevertheless, the technology described by Kagemann et al. provides a glimpse into the promising future of OCT towards assessment of outflow function in patients with glaucoma.