What is the trabecular meshwork of the eye?
The trabecular meshwork is a tissue located in the anterior chamber angle of the eye, and it is a crucial determinant of intraocular pressure values because of its resistance to the evacuation of aqueous humor from the eye. Both nutrition of lenses and maintenance of IOP are critical for a normal visual process.
Where does the trabecular meshwork drain into?
Schlemm’s canal
The majority of fluid draining out of the eye is via the trabecular meshwork, then through a structure called Schlemm’s canal, into collector channels, then to veins, and eventually back into body’s circulatory system.
Where does the canal of Schlemm drain to?
Canal of Schlemm
| Location | Internal scleral sulcus |
|---|---|
| Function | Drains the aqueous humor from the anterior chamber of the eye into the veins of eyeball |
| Drains to | Ophthalmic veins |
What causes blockage of trabecular meshwork?
In closed-angle glaucoma, both the uveoscleral drain and the trabecular meshwork become blocked. Typically, this is caused by a damaged iris (colored part of the eye) blocking the outlet. Blockage of either of these outlets leads to an increase in pressure inside your eye.
What happens when trabecular meshwork is blocked?
Angle-closure glaucoma occurs when the iris is positioned against the trabecular meshwork, blocking the flow of aqueous out of the eye and raising the intraocular pressure. When this occurs acutely, the pressure can be very high. The patient has pain and often nausea and vomiting.
What is the trabecular meshwork made of?
connective tissue
The structure is composed of connective tissue beams and sheets or lamellae covered by TM cells. Three consecutive regions define the filtering portion of the TM: uveal meshwork, corneoscleral meshwork and juxtacanalicular region (JCT) also often called the cribriform region.
Can glaucoma be hereditary?
The most common type of glaucoma, primary open-angle glaucoma, is hereditary. If members of your immediate family have glaucoma, you are at a much higher risk than the rest of the population. Family history increases risk of glaucoma four to nine times.
Does glaucoma cause drainage?
Open-angle glaucoma is the most common form of the disease. The drainage angle formed by the cornea and iris remains open, but the trabecular meshwork is partially blocked.
What is canal of Schlemm?
Schlemm’s canal is a circular lymphatic-like vessel in the eye. It collects aqueous humor from the anterior chamber and delivers it into the episcleral blood vessels. Canaloplasty may be used to widen it.
What is glaucoma and what causes it?
Glaucoma is the result of damage to the optic nerve. As this nerve gradually deteriorates, blind spots develop in your visual field. For reasons that doctors don’t fully understand, this nerve damage is usually related to increased pressure in the eye.
Can glaucoma be cured?
The damage caused by glaucoma can’t be reversed. But treatment and regular checkups can help slow or prevent vision loss, especially if you catch the disease in its early stages. Glaucoma is treated by lowering your eye pressure (intraocular pressure).
Can you have narrow angles without glaucoma?
Although not everyone with narrow angles actually develops glaucoma, careful evaluation of the angle structure can identify who is at greatest risk. The angle structure is determined by an examination called gonioscopy which is performed with a special contact lens called a gonioprism.
What is the trabecular meshwork?
The trabecular meshwork is a connective tissue network that extends between the tip of the scleral spur and the Schwalbe’s line (external margin of the corneal endothelium). It contains trabecular cells (trabeculocytes) separated by intratrabecular free spaces.
What is the canal of Schlemm?
(Canal of Schlemm labeled at center left.) Schlemm’s canal is a circular lymphatic-like vessel in the eye that collects aqueous humor from the anterior chamber and delivers it into the episcleral blood vessels via aqueous veins. It is named after Friedrich Schlemm (1795–1858), a German anatomist.
How is a microcatheter used to treat 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.
How does the canal of Schlemm collect the aqueous humor?
Instead, the endothelial cells of the canal of Schlemm collect the aqueous humor by a specialized form of transcellular transport.
