Retina Unit

Related Programs


St. Michael’s Hospital

30 Bond St.,
Toronto, ON
M5B 1W8
The main entrance is located near Queen St. East and Victoria St. The Bond St. entrance is not open to the public at this time.

8th Floor
Donnelly Wing


The retina is a thin layer of nerve tissue lining the back of the eye. It is made up of millions of light sensitive cells that respond to light focused through the cornea and lens. The retina transmits this information through the optic nerve to the brain where vision is perceived. The macula is the centre of the retina, which provides clear, central vision. The vitreous is a transparent gel that fills the eyeball and allows images to focus on the retina without distortion. There are a number of ocular diseases that specifically involve the retina, vitreous or both.

A retina specialist is an ophthalmologist (an eye physician and surgeon) with advanced training in the diagnosis and treatment of eye disorders involving the retina and vitreous. A retina specialist is prepared to medically or surgically treat such disorders as macular degeneration, macular holes, macular puckers, diabetic retinopathy, retinal vascular disease, tears and detachment of the retina, and severe ocular injuries, infections or inflammations.

Age-related macular degeneration

Age-related macular degeneration (AMD) is a disease that results in degeneration or breakdown in the centre of the retina, or macula.  There are two forms of AMD: dry AMD and wet AMD, both of which may lead to progressive loss of central vision.  There are treatments for AMD to reduce the risk of vision loss and in some cases return vision that has already been lost.

Diabetic retinopathy

Diabetic retinopathy is a complication of diabetes that involves damage to the retinal blood vessels. Retinal blood vessels may leak, causing swelling of the retina (macular edema) or close off completely. In other cases, abnormal new blood vessels may grow on the surface of the retina leading to bleeding, retinal detachment and/or vision loss.

Retinal vein occlusion

A retinal vein occlusion is a blockage of the small veins that carry blood away from the retina.  This may lead to swelling of the retina, a deterioration (worsening) in retinal blood flow and/or vision loss.

Macular pucker

Epiretinal membrane (also referred to as macular pucker, surface wrinkling retinopathy, or cellophane maculopathy) refers to the formation of a semitransparent scar tissue on the surface of the retina. With time, this scar tissue can contract and result in distortion of the underlying retina and/or macular edema (swelling).

Macular hole

A macular hole is a small full-thickness defect that may form in the centre of the retina, or macula. A macular hole may cause a loss in central vision and require surgery for repair.

Retinal dystrophy

A retinal dystrophy is a condition associated with reduced or deteriorating vision in both eyes. Retinal dystrophy is not one single condition, but the general name given to a wide range of eye conditions (for example, Retinitis Pigmentosa). Dystrophy means a condition that a person is born with. Retinal means relating to the retina.

Posterior vitreous detachment

A posterior vitreous detachment (PVD) occurs when the collagen fibers that make up the vitreous cavity condense, causing the gel to pull forward. Patients typically complain of seeing central floaters and/or flashes of light, usually in their peripheral vision. This is a normal age-related phenomenon, but in some patients, it can be associated with a retinal tear or detachment.

Retinal tear and detachment

Usually with age, vitreous, the clear gel filling the eye, pulls away from the surface of the retina in a process called posterior vitreous detachment. This usually occurs without damaging the retina, but in some cases the vitreous may pull hard enough to tear the retina in one or more places. Fluid can pass through the tear and begin accumulating behind the retina, causing a retinal detachment. A retinal detachment is often associated with significant vision loss and requires surgical repair.


Dr. Filberto Altomare
Dr. Alan Berger
Dr. David Chow
Dr. Louis Giavedoni
Dr. David Wong
Dr. Rajeev Muni
Dr. David Assaad
Dr. Brad Kates
Dr. Mark Mandell