The canal of Schlemm, or the scleral venous sinus, is a circular canal found within the posterior part of the corneoscleral junction (the junction of the cornea and the sclera (the white of the eye)). The function of Schlemm's canal is to collect the aqueous humor (transparent water-like fluid) from the anterior chamber of the eyeball and deliver it to the veins of the eyeball. Schlemm's canal is named after Friedrich Schlemm (1795–1858), a German anatomist.

Schlemm's canal is an endothelium-lined tube, resembling that of a lymphatic vessel. On the inside of the canal, nearest to the aqueous humor, it is covered and held open by the trabecular meshwork (tissue located in the anterior chamber angle of the eye). This creates outflow resistance against the aqueous humor.

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