Schlemm's canal

Schlemm's canal
Enlarged general view of the iridial angle. (Labeled with older label of 'sinus venosus scleræ' at center top.)
The upper half of a sagittal section through the front of the eyeball. (Canal of Schlemm labeled at center left.)
Latin	sinus venosus sclerae
Gray's	subject #225 1005

Schlemm's canal, also known as canal of Schlemm or the scleral venous sinus, is a circular channel in the eye that collects aqueous humor from the anterior chamber and delivers it into the bloodstream via the anterior ciliary veins.^[1]

The canal is essentially an endothelium-lined tube, resembling that of a lymphatic vessel. On the inside of the canal, nearest to the aqueous humor, it is covered by the trabecular meshwork, this region makes the greatest contribution to outflow resistance of the aqueous humor.

Named after Friedrich Schlemm (1795-1858), a German anatomist.

Role in glaucoma

The canal transfers approximately 2-3 microliters of aqueous humor per minute.^[2] If debris builds up, due to infection or injury in the aqueous humor, the canal is blocked and glaucoma is the result.

Canaloplasty

Canaloplasty is an advanced, nonpenetrating procedure designed to enhance and restore the eye’s natural drainage system to provide sustained reduction of intraocular pressure. Canaloplasty utilizes microcatheters in a simple and minimally invasive procedure. To perform a canaloplasty, a surgeon will create a tiny incision to gain access to Schlemm's canal. A microcatheter circumnavigates Schlemm's canal around the iris, enlarging the main drainage channel and its smaller collector channels through the injection of a sterile, gel-like material called viscoelastic. The catheter is then removed and a suture is placed within the canal and tightened. By opening Shlemm's canal, the pressure inside the eye is relieved. Long term results are available, published in May 2009 in the Journal of Cataract and Refractive Surgery.[1] [2][3][4]

See also

• Intraocular pressure
• Ocular hypertension

References

External links

• Histology at BU 08005loa
• Diagram
• Diagram

v • d • e Sensory system – visual system – globe of eye (TA A15.2.1-6, GA 10.1005) Fibrous tunic (outer) Sclera Episcleral layer • Schlemm's canal • Trabecular meshwork Cornea Limbus • layers (Epithelium, Bowman's, Stroma, Descemet's, Endothelium) Uvea/vascular tunic (middle) Choroid Capillary lamina of choroid • Bruch's membrane • Sattler's layer Ciliary body Ciliary processes • Ciliary muscle Iris Stroma • Pupil • Iris dilator muscle • Iris sphincter muscle Retina (inner) Cells Photoreceptor cells (Cone cell, Rod cell) → (Horizontal cell) → Bipolar cell → (Amacrine cell) → Retinal ganglion cell (Giant retinal ganglion cells, Photosensitive ganglion cell) Muller glia Layers Inner limiting membrane • Nerve fiber layer • Ganglion cell layer • Inner plexiform layer • Inner nuclear layer Outer plexiform layer • Outer nuclear layer External limiting membrane • Layer of rods and cones • Retinal pigment epithelium Other Macula • Foveola • Fovea • Optic disc (Cup) Anterior segment Anterior chamber • Aqueous humour • Posterior chamber • Lens (Capsule of lens, Zonule of Zinn) Posterior segment Vitreous humour Other Ocular immune system • Tapetum lucidum • Keratocytes eye navs: anat/adnexa anat/pathways/physio/dev, noncongen/congen/neoplasia, eponymous signs, proc

This eye article is a stub. You can help Wikipedia by expanding it. v • d • e