What is the Vitreous?

The vitreous, also known as the vitreous humor, is a gel-like substance that fills the inside of the eye, occupying the space between the lens and the retina. It plays a crucial role in the development of the eye and in supporting the overall structure of the eye after we are born.

Composed mainly of water, the vitreous humor is a transparent, colorless gel that consists of a network of collagen fibers and various other molecules. It is synthesized during the early stages of development and persists throughout life. It is not renewed.

Function

The primary function of the gel is to provide mechanical support to the eyeball. It helps maintain the spherical shape of the eye, which is essential for proper focusing of light onto the retina. Additionally, the vitreous acts as a shock absorber, protecting the delicate structures within the eye from external forces or impact.

Moreover, this clear gel plays a role in the optical system of the eye. By virtue of its transparency, it transmits light, allowing it be focused on the retina. The retina converts light into electrical signals that are then transmitted to the brain, thus creating “vision.” The smooth, uniform consistency of the vitreous helps to ensure that light rays are not scattered or distorted as they travel through the eye.

Posterior Vitreous Detachment

While the vitreous is mostly a stable, gel-like substance, it can undergo changes that can impact vision. With age, the vitreous may gradually shrink and develop small pockets of fluid. This is known as a posterior vitreous detachment (PVD). This can lead to the formation of floaters, which are perceived as tiny specks or threads that seem to float across the field of vision. Although floaters are usually harmless, a sudden onset of numerous floaters or flashes of light may be a sign of a retinal tear. A retinal tear can cause a retinal detachment, which requires immediate medical attention. Sudden onset of floaters should always be checked by your eye doctor.

The vitreous is most important for normal development of the eye. Once we are born, it indirectly maintains various functions of the retina and the lens. Understanding the role of the vitreous can help appreciate its importance in maintaining healthy vision and identifying potential eye problems.

If you would like to schedule an appointment, please call us (877) 245.2020.

Nader Moinfar, M.D., M.P.H.
Retina Specialist
Orlando, FL

Floaters from Vitreous Hemorrhage

Vitreous hemorrhage from various causes can cause floaters.

Vitreous hemorrhage can cause floaters in the eye.  Bleeding inside the eye is called vitreous hemorrhage.  Symptoms of this type of bleeding range from a showere of floaters to incomplete darkness (lots of blood).

Floaters due to blood can not be distinguished by other types of floaters based upon appearance.  Often floaters from hemorrhage have appeared suddenly and don’t necessarily last as long as chronic (long-lasting) floaters, but they can.

Causes of Vitreous Hemorrhage

Any bleeding into the vitreous is called vitreous hemorrhage.  Hence, there are a variety of causes of bleeding into the vitreous;

  1. Retinal tears
  2. Retinal Detachments
  3. Trauma
  4. Diseases of the retina (eg. proliferative diabetic retinopathy)
  5. Complications of retinal vascular disorders
  6. Posterior Vitreous Detachment

Treatments

For all intents and purposes, blood in the vitreous does not cause long-lasting damage. It is most important to establish the underlying cause of the bleeding and treat that disorder whenever possible. 

For dense vitreous hemorrhages, it may indeed be prudent to consider a vitrectomy to remove the blood to restore vision, but more importantly, and to allow the retina specialist to perform a thorough examination of the eye with the blood removed.

Retinal Tears and Bleeding

As an example, a retinal tear can cause a vitreous hemorrhage if the tear rips across a retinal blood vessel and causes bleeding.  There may be too much blood to actually visualize a retinal tear.  Keep in mind, retinal tears can lead to retinal detachments.

Retinal detachments can be potentially blinding and, in cases of all retinal tears, we would like to treat the tear before a retinal detachment develops.

Vitreous Hemorrhage Can Resolve

Blood in the vitreous usually absorbs and can clear on with a vitrectomy.  There is no specific timing of this and it can take weeks or even months.  Sometimes, blood does not clear on its own and vitrectomy may be necessary. 

If you would like to schedule an appointment, please call us (877) 245.2020.

Nader Moinfar, M.D., M.P.H.
Retina Specialist
Orlando, FL

What is FOV?

FOV stands for Floater Only Vitrectomy.  In my experience, this is the common name of the basic operation performed by a retina specialist called vitrectomy.

Vitrectomy and FOV, therefore, are synonyms.  Vitrectomy is the standard operation performed by all retina specialists (for all reasons) whereas FOV refers to a vitrectomy performed for the removal of only (just) floaters.

Vitrectomy

Vitrectomy is the operation to remove the vitreous.  The vitreous is the gel-like substance that fills the back of the eye.  

The vitreous may be removed;

  • To remove a vitreous hemorrhage (blood)
  • Remove a foreign body
  • Repair
    • Retinal detachment
    • Macular hole
    • Epiretinal membrane
  • Remove floaters

Types of FOV or Vitrectomy

All modern types of FOV are basically the same.  They involve the creation of 3 holes in the eye:

  1. Left hand
  2. Right hand
  3. Infusion port to keep the eye filled with saline during the operation

There are slight changes in nomenclature to distinguish the size or thickness of the instruments used to enter the eye.  The size of the sclerotomies (holes) the instruments create naturally vary in size.  The thicker instruments create large holes and vice versa.  20 gauge instruments are the thickest and require sutures to close the sclerotomies.  23 and 25 gauge instrumentation create tinier sclerotomies and suture closure is up to the discretion of the retina specialist.

What Replaces the Vitreous?

The vitreous is cut away rapidly in very tiny miniscule pieces and is replaced by artificial saline solution.  As the operation is proceeding, a tube is constantly infusing saline into the eye.  After the operation is complete, your eye replaces the saline with aqueous humor in a matter of a couple days.

How is FOV Different than Vitrectomy

It’s not.  It’s exactly the same.  After the vitreous is removed, the operation is essentially over.  FOV for floaters is exactly the same as FOV for vitreous hemorrhage – the goal of both is to simply clear opacities from the vitreous to create a clear path for vision.

If you would like to schedule an appointment, please call us (877) 245.2020.

Nader Moinfar, M.D., M.P.H.
Retina Specialist
Orlando, FL

Jon Doe