Tag: PVD

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My Opinion Retinal Detachments

Excercise After PVD is Safe

Retinal Detachments and Retinal Tear

Updated by Mike Rosco, MD on 3/23/23 at 1:03 PM

I believe exercise after sustaining a posterior vitreous detachment (PVD) to be safe.  Many doctors recommend a “no exercise” period after a PVD to decrease the risk of retinal tear and retinal detachment.  This does not make sense to me.

PVD Causes Retinal Tear

A retinal tear may occur after a posterior vitreous detachment, but in my opinion, the chance of a tear occurring is the same whether or not you exercise.

The vitreous gel inside your eye normally separates, or detaches, from the retinal surfaces with age. It happens to everyone as we get older. A PVD will occur earlier in life due to increased nearsightedness, previous eye surgery, certain trauma, and so on. 

After a PVD occurs, there are physical changes within the eye. The vitreous now occupies less space. Though it’s “detached,” it doesn’t separate completely from the retinal surface. As the eye moves back and forth, the vitreous remains tethered in certain areas. It’s in these areas where the retina can potentially tear.

Statistically, a retinal tear will occur during the first six weeks of onset of a PVD.

Does Exercise Increase the Chance of Retinal Tear?

The concern about exercise is related to increased motion/bouncing of the eye. The thought is that increased movement increases the chance of a retinal tear.

This might be a valid concern except for two arguments: 1) Each evening during REM sleep (a necessary stage of sleep), the eyes beat back and forth faster than any activity we perform while awake, and 2) After the six week period, evidence shows that the retina hasn’t “healed” in any significant way. 

During REM, the speed of the eye movements (think of what your eyes do when you reach the end of a sentence) approaches that of reading, however the extent to which the eyes move is more extreme than these reading movements. And it occurs for hours during a normal sleep. 

Thus, every night your eyes sustain greater forces during REM than while you are awake.

As mentioned, there are no known physical changes to either the retina or vitreous after six weeks. For instance, the retina does not become stronger or thicker after a PVD, hence the chance of tearing should be the same.

Weightlifting is definitely safe.

What Does this Mean?

Remember, this is my opinion. If you were my patient (and I remind you that it does not make you my patient by merely reading this article), I’d advise you exactly as I’ve written here. I think my arguments allowing exercise are evidence-based and worthy of discussion with your own doctor.

Lastly, if you are at risk for developing a tear, wouldn’t you want it to occur during the time we are being extra vigilant?

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Retina Treatments Uncategorized

Ocriplasmin Approved for VMT and Macular Holes

 

A Posterior Vitreous Detachment May Cure VMT
Posterior Vitreous Detachment “Separates” from the Retinal Surface

Ocriplasmin, or Jetrea,  has been FDA approved.  The drug is approved only for a retinal condition called vitreomacular traction (VMT) or vitreomacular adhesion (VMA).  The VMT may or may not be associated with a macular hole.

What is VMT?

VMT is basically an incomplete, or partial, PVD (posterior vitreous detachment) with subsequent “pulling” on the macula.  This “pulling” is also known as traction and can cause microscopic elevation on the macula and may lead to macular hole formation.

Ocriplasmin (previously known as microplasmin) may be an effective way to complete this PVD and chemically cleave the adhesion between the vitreous and macula.

Current treatment for vitreomacular traction and macular hole is surgical vitrectomy.

Intraocular Injection

Ocriplasmin is given as an intravitreal injection.  The medicine is injected directly into the eye as are other intraocular injections of Avastin, Lucentis and Ozurdex.

Ocriplasmin is a proteolytic enzyme which may chemically cause a more complete separation of the vitreous and surface of the retina.  Cleaving the adhesion between the vitreous and macular surface may improve vision and the macular hole, if present.

Results of Study

In the study presented to the FDA, patients received one injection of ocriplasmin.

  • Jetrea caused resolution of VMT in about 26% of patients and caused a complete PVD in about 13%.
  • Vision improved in a selected group; 25% of those with decreased vision of 20/50 or worse.
  • Macular holes “closed” (i.e. fixed) in 40% of patients.

What Does This Mean?

This is a novel drug to chemically separate the vitreous from the retina.  It has the potential to be an alternative to vitrectomy, the present accepted method for treating VMT and macular hole.

Intravitreal injections are delivered routinely in the office, thus, there is virtually no technique for physicians to “learn.”

The results, however, to not compare with the efficacy of vitrectomy eye surgery.  VMT is “cured” almost all of the time and macular holes are repaired at least 90% of the time with a single surgical attempt.

We really don’t know if the safety of this particular injection is similar to other eye injections. Historically, other eye injections compare equally with vitrectomy with respect to intraocular infection and retinal detachment.

Lastly, for the floater community, I don’t believe this to be a substitute for surgery, but may be used as an adjunct to create a PVD before considering “floater only vitrectomy (FOV)”.  Creating a PVD may make the floaters worse by changing the location +/- causing additional floaters.

As the use of Ocriplasmin becomes adopted by retinal physicians, it will be exciting to see if the efficacy of the drug can be improved and whether or not there will be other indications.  For instance, will the results improve with repeated injections?

 

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Treatments

New Drug Induces Posterior Vitreous Detachment (PVD)

A Posterior Vitreous Detachment May Cause a Retinal Tear
Posterior Vitreous Detachment "Separates" from the Retinal Surface

A new drug, Ocriplasmin, is seeking FDA approval for treatment of some retinal disorders.  Ocriplasmin (also known as microplasmin) may help patients with vitreomacular traction syndrome (VMT) and macular hole by chemically inducing a PVD.

The drug may gain Priority Review status by FDA later this year.  Priority Review is a special designation for drugs that show either a significant improvement over existing therapies, or where there is not current therapy.

VMT and macular hole are two similar conditions where vitreous remains adherent to the macula causing pulling and stretching of the macular area.  This physically disrupts the macula causing decreased vision and /or  distortion.

Current therapy includes surgery to separate the vitreous from the underlying retinal tissue.  Ocriplasmin may achieve the same goal by chemically separating this interface.

The drug has been given by intravitreal injection.

Posterior Vitreous Detachment (PVD)

The excitement in the retinal field stems from the fact that so many retinal diseases are caused by the vitreous.  Many macular disorders are probably caused by interaction between the macula (retina) and the adherent vitreous.

Currently, the vitreous separates from the retina either naturally as we get older or it is induced surgically.

As we age, the vitreous proteins degenerate as does the “glue” keeping the vitreous adherent to the retina.  At some point in everyone’s life a posterior vitreous detachment naturally occurs. At the time of a PVD, there is a naturally increased risk of sustaining a retinal tear.  Retinal tears may develop into retinal detachments.

During surgery for many retinal diseases, surgical induction of a PVD is often helpful to achieve the surgical goal.  There are, however, potential complications from pulling the vitreous away from the retina.  There is a greater chance of surgically causing retinal tears!

What Does This Mean?

Chemical induction of a PVD would be a great alternative to surgery.  In theory, the chance of retinal tear is greatly reduced by avoiding surgery.  Hence, it is an attractive and potentially safer alternative compared to surgery because the complications may be fewer.

Just as important, however, is whether the new treatment is as effective as the current treatment.  In other words, will simply injecting the new drug improve patient results as compared to surgical techniques.

If the drug gets approved by the FDA, it will be “approved” for VMT/macular holes.  Once on the market, however, it will be likely be adopted for use in many other retinal conditions.

Used as an adjunct to surgery, the complication rate of retinal tears might be decreased making “surgery” much safer.

 

 

 

Categories
Treatments

Vitreous Causes Most Retinal Disease

The vitreous causes most diseases of the retina.

Retinal tears, retinal detachments, macular holes, epiretinal membranes, macular edema, vitreomacular traction, diabetic retinopathy, diabetic macular edema and diabetic retinal detachments are all related to the vitreous.

We suspect even wet macular degeneration may play a role as well, but there is no conclusive evidence.

Even floaters, though not necessarily a disease, can be caused by abnormal optical properties of the vitreous.

Retinal Tears and Retinal Detachments

The vitreous is physically attached to the retina.  If you divide the eyeball into a front half and back half while looking straight at the eye, the vitreous and retina are most adherent in the front half.

A PVD, or posterior vitreous detachment, means that the watery gel has separated from the retina in the back half of the eye, or, the “posterior vitreous.”

Rhegmatogenous Retinal Detachment with Retinal Tears or Holes
Front Half (Grey Ring), "Posterior" Half (Central Grey Ring)

 

The anterior half remains adherent to the retina.

Hence, if enough force is generated through the vitreous and pulls on the retina, a retinal tear develops and is almost always in the front of the eye.

Retinal tears can cause retinal detachments.  This is why I often recommend a vitrectomy in patients with multiple tears.  By removing the vitreous, I am removing the causative agent.

Epiretinal Membranes and Macular Holes

In most cases of epiretinal membranes, a PVD has occurred.  In most cases of macular holes, a posterior vitreous detachment has not occurred.

Macular Edema

Swelling of the macula from various causes, but including diabetic retinopathy, usually occurs before a PVD occurs, that is, the vitreous is still adherent to the macular region.

What Does this Mean?

In many cases,  a posterior vitreous detachment can be dangerous, as in the case of a retinal detachment or retinal tear.

In many more cases, a PVD might be “therapeutic.”

There is no conclusive proof, but separation of the vitreous interface can sometimes prevent macular edema, is probably going to be shown to reduce diabetic macular edema, may prevent retinal detachment from proliferative disease and may prevent two other conditions called vitreomacular traction (VMT) and macular holes.

Presently, a posterior vitreous detachment is a purely natural event, that is, it happens to everyone.  Surgically, a posterior vitreous detachment can be induced, or caused, at the time of vitrectomy surgery.  This can be a risky part of the procedure as inadvertent retinal tears may develop.

In theory, however,  many of the aforementioned conditions might be avoided altogether or at least improved…leading to better vision or preventing further loss.

On the horizon, an enzyme, given as an injection that might chemically cause a PVD.

 

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