5.  Surgical Complications from cataract surgery can be a relative emergency.  On occasion, a portion of the cataract may dislodge during cataract surgery and slip into the vitreous.  Patients usually do not see well and may have trouble with high intraocular pressure.

• Cause – variations in anatomy, surgical complications
• Concerns – the biggest medical concern is the high eye pressure, it may cause permanent damage and be very painful.
• Comments – this is one of the biggest “nightmares” of a cataract surgeon, yet it really is not a big deal to rectify as long as referral to a retina specialist is done early.

4.  Posterior Vitreous Detachment – while usually benign, a PVD can cause a retinal tear and possibly a retinal detachment.  With time, the vitreous (the gel inside the eye) separates from the surface of the retina.  This is a normal event as we get older, but it puts us at the highest risk of developing a retinal tear.

• Cause – the separating/degenerating vitreous changes forces inside the eye causing flashes and floaters.
• Concerns – there is no way to tell, without examination, if a tear has developed.
• Comments – same approach as with new “floaters,” can’t tell if there is a tear.

3.  Retinal Tears cause retinal detachments.  The usual cause of a tear is from a Posterior Vitreous Detachment and rarely trauma.  Retinal holes, usually from a condition called Lattice Degeneration, may cause a retinal detachment, too.  Retinal tears may be treated to prevent a retinal detachment, hence, the “emergency.”

• Cause – either a hole or tear allows fluid to accumulate underneath the retina.
• Concerns – permanent loss of vision may occur if the macula becomes detached.  Blindness is possible.
• Comments – progressive loss of peripheral vision should be communicated to your eye doctor immediately.

2.  Endophthalmitis is a true medical emergency and is usually caused by infection of the inside of the eye.  There is usually a history of recent eye surgery.

• Cause – usually bacterial infection after eye surgery.  Rarely, severely immuno-compromised patients can acquire this infection from an “endogenous” source.
• Concerns – Blindness can occur within 24 hours.
• Comments – common signs of infection following eye surgery include decreased vision and usually, pain.

1.  Retinal Detachment – retinal detachments can cause permanent loss of vision or blindness.  The critical aspect of a retinal detachment is the state of the macula, that portion of the retina serving central vision.  If the macula is detached, central vision is already compromised.  While reattachment will likely improve vision, the prognosis is not as good as if surgery were performed before macular detachment.

• Cause – retinal tears or holes.  Usually preceded by flashes or floaters, but may be asymptomatic.
• Concerns – state of the macula, is it attached?
• Comments – the most emergent retinal detachment is where the macula is “on,” or attached, but the portion of the detachment is above the macula.  Gravity will most likely act quickly to detach the macula.  Every effort is made to operate before the macula becomes affected!

“Randy”

Randall V. Wong, M.D.

Ophthalmologist, Retina Specialist
Fairfax, Virginia

There are really only a couple of true retinal eye emergencies.  I’ve listed the “top ten,”  remember that there are many ways to define an emergency.  All involve loss of vision, or at least a change in vision, and that alone probably qualifies as an “emergency.”  By the way, if you have sustained any of these symptoms, please call your doctor.  This article, and web site, is not intended to replace medical advice.

So here goes;  my “Top Ten” Retinal Emergencies;

10.  Vitreous hemorrhage – the symptoms of a vitreous hemorrhage can range from the onset of sudden floaters to rather impressive loss of vision, depending upon the amount of bleeding into the vitreous.

• Causes – retinal tear, proliferative diabetic retinopathy
• Concerns – an undiagnosed tear can lead to a retinal detachment
• Comments – blood in the eye is not toxic, the blood is physically blocking light from hitting the retina

9.  Vascular Occlusions – either vein occlusions or artery occlusions.  Patients experience sudden loss of vision.

• Causes
• Vein Occlusions – may be associated with hypertension or diabetes, often healthy individual
• Artery Occlusions – look for cardiovascular disease/stroke
• Concerns – may develop “neovascular” glaucoma
• Comments – treatments include laser treatment, Ozurdex (vein).

8.  Submacular Hemorrhage – sudden bleeding underneath the macula/retina.  Causes a dark area in the vision.  Usually the peripheral vision is normal.

• Causes – valsalva, trauma, macular degeneration
• Concerns – source of the bleeding
• Comments – valsalva (aka straining) has the best prognosis, remember blood underneath the retina is not toxic

7.  “Wet” Macular Degeneration – rapidly (days to weeks) decreasing vision, distortion.

• Causes – fluid/blood accumulating in the macula
• Concerns – look for abnormal blood vessels (neovascularization)
• Comment – fluorescein angiography is helpful

6.  Uveitis/Iritis – this is inflammation inside the eye, not unlike arthritis.  Patients may experience pain, sensitivity to light, decreased vision.  Eye may turn red.

• Causes – endogenous, some rheumatologic diseases, trauma
• Concerns – relief of pain, may look for associated systemic disease
• Comment – usually steroids play a big role in controlling this

To Be Continued…

“Randy”

Randall V. Wong, M.D.

Ophthalmologist, Retinal Specialist
Fairfax Virginia

Both Avastin and Lucentis are anti-VEGF treatments for wet macular degeneration.  Both are manufactured by Genentech (Roche).  A small study just published found no clinical difference between the two drugs, that is, one worked as well as the other.

There has been quite a debate over the difference between the two drugs and their ability to treat wet macular degeneration.  There are differences in cost, FDA approval, etc., but this is the first study that has compared the two drugs head to head.

The large difference in cost between the two drugs has led to speculation that the popular use of Avastin among retina specialists is due to price alone.  Avastin costs less than $50 per injection whereas Lucentis is priced at $2000 per injection.  Supporters of Avastin (including yours truly) feel that the use of Avastin is justified by the excellent results.

Other than price there are differences in the number of isoforms that the molecules block; Avastin blocks more isoforms than Lucentis, but is this significant in the eye?  No one knows.  It seems not to matter.

What Does this Mean? This study was a retrospective study, that is, the results were determined looking backwards.  One weakness of retrospective studies is that there are too many variables between patient groups to allow a true “head to head” comparison.  The result, too much bias in the study and it is difficult to make ture, concrete conclusions.  It doesn’t mean that retrospective studies are worthless, but you must keep in mind there may be flaws in the conclusions.

A prospective, randomized study is really the gold standard.  In these studies, similar patients (similar in age, vision, race, etc.) are treated exactly the same and differ only in the treatments they receive.  In this case, similar patients would be randomly treated with either Avastin or Lucentis.  The patients are treated with the exact same protocol with respect to dosage, frequency of injection, etc.  The groups are then followed for a given length of time.

The results of prospective studies have far less bias and results are taken to be more meaningful.  An NIH sponsored prospective study is underway comparing Avastin vs. Lucentis.

For now, there seems to be no clinical advantage to either drug.

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
Fairfax Virginia

The major problem with wet macular degeneration is that the “wet” abnormal blood vessels tend to affect the macula.  This usually causes decreased vision and distortion.  Home monitoring, or self-monitoring, is based on the premise that new distortion may signify presence of neovascularization.

Patients with wet macular degeneration have two major concerns; recurrence in the same eye and wet macular degeneration developing in the other eye.  To alleviate their fears, doctors have long been recommending home monitoring as a method to catch the disease as early as possible.

Distortion from “wet” macular degeneration is similar to the “Princess and the Pea,” where the abnormal vessels are trying to sandwich themselves between the layers of the retina.  This causes the retinal surface to become uneven which translates into distortion.

Amsler Grid Testing – The Amsler Grid is used on a daily basis, testing each eye separately.  In this way, a patient with macular degeneration will become familiar with their own pattern of distortion.  Any new waviness should be reported to their doctor.  This may be a sign of active “wet” macular degeneration.

An electronic version of the Amsler Grid is available at “MyVisionTest.com.”  There is also a link on the left side panel if you ever forget.

The ForSeeHome™ AMD Monitor is the first telemedicine device for the home.  According to the company web page, this device offers self-monitoring of patients with known macular degeneration.  It is not a diagnostic tool, but monitors changes in distortion.  This information can then be transferred to the eye doctor for review.  The device has received FDA “510(k)” clearance.

What Does This Mean? The idea of self-monitoring is to catch the “wet” form as early as possible.  Early detection of wet macular degeneration usually translates to a better outcome.  In my experience patients with wet macular degeneration are pretty motivated to self-test regularly and the Amsler Grid seems to be a very good, cheap, and reliable test.  Remember that the macula is very sensitive and any change in distortion is usually pretty obvious.

It seems that a new telemedicine device might be “overdoing” it, at least from what I can tell from the web page and the press release.  It does not make a diagnosis and examination by the doctor is still necessary.

I see three scenarios; however, where this might be useful; 1) a patient is unable to tell, himself, if there are changes in his own vision (yes, it happens), 2)  a patient’s vision is so poor that subtle changes are unnoticed and 3) the device picks up earlier changes than can be noticed by the average individual, that is, the device is super-sensitive.

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
Fairfax, Virginia

PR: wait… I: wait… L: wait… LD: wait… I: wait… wait… Rank: wait… Traffic: wait… Price: wait… C: wait…

Last week, I introduced “Mrs. Ozurdex,” an elderly female who has a central retinal vein occlusion in her right eye.  Several weeks ago, I implanted a sustained release steroid delivery system, called Ozurdex® (Allergan).  Ozurdex is indicated, and FDA approved, for the treatment of CRVO.

If you recall, another patient, “Mr. Ozurdex” had a branch retinal vein occlusion.  He, too, received Ozurdex.  After only two weeks there seemed to be impressive recovery of his vision!  Mrs. Ozurdex has a poorer prognosis due to the difference in the diagnosis, that is, a CRVO has more dramatic loss of vision and a poorer visual prognosis.

Still, Ozurdex is indicated to treat both.

Mrs. Ozurdex returned last Thursday.  I wanted to make sure that she was healing well after the injection and that her intraocular pressure (IOP) was within normal limits. I did not expect any change in her vision, despite Mr. Ozurdex’s shocking improvement.

Mrs. Ozurdex came to the office as happy as ever (remember “glass is half full?”).  Her eye was comfortable, her eye pressure was normal, yet there was no change in her vision.

What Does This Mean? Actually this means very little in terms of her vision.  It is too early to assess.  I needed to see her to make sure that there were no complications from the injection of Ozurdex, namely; bleeding, retinal detachment and pressure changes.  This is normal protocol.  While it would have been nice to see some change in vision, I needed to insure that there were no problems.

Much of what a retinal surgeon does is to keep status quo.  We also aim to limit complications.  While I am now satisfied we have not caused additional harm to Mrs. Ozurdex, I am still keeping my fingers crossed for her.  We should see some improvement after one month.  The drug will be released for up to 6 months.

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retinal Specialist
Fairfax Virginia

I am happy and honored to introduce Dr.  Chris Renner as a contributor to RetinaEyeDoctor.com!  He and I practice closely together in Northern Virginia.  I asked him to write about Low Vision. – “Randy”

What is Low Vision?

The great advances in treatment of eye disease have prevented many cases of blindness, however, many patients suffer partial visual loss and are left with reduced visual function.  This limited level of vision, whether lack of visual clarity or loss of peripheral vision is called “low vision.”  Common causes of low vision are macular degeneration, diabetic eye disease and stroke.

Low vision describes a decreased level of visual function and inability to perform the normal tasks of life even when you are wearing your best glasses.  Maybe you have difficulty reading the newspaper or computer screen, or writing a check or reading your mail.  A low vision evaluation can help you find the right tools to allow you to perform your normal daily activities.

A low vision evaluation and treatment will not improve your eye health or restore your sight.  The goal is to restore function, the ability to perform the tasks in day-to-day life. I ask each low vision patient to list three activities that they are struggling with and we focus on improving their ability to complete those tasks. This might require special eyeglasses, magnifiers, aids or computer programs.  Most patients have several different low vision “tools,” just like you might have several different screwdrivers in a toolbox. Most low vision devices help you by providing significant magnification.

The most powerful (and simplest) tool for allowing the patient with low vision to read is called a reading microscope.  It is a special high-power pair of eyeglasses, possibly with prism, which allows you to see items approximately five times larger than usual.  A reading microscope has the advantage of being relatively inexpensive, small and portable, and allows you to keep your hands free to hold whatever you are reading.  The disadvantage is that you must hold your reading material approximately four inches from your nose and can read only a few words at a time. Reading microscopes are the most popular form of low vision device.

Other low vision devices include hand magnifiers, spotting telescopes, closed circuit television cameras, visual field expanders and computer software to magnify or read text on the computer.  Each of these items can be extremely helpful in the right circumstances for the right patient.  In Part 2 I will discuss hand magnifiers and telescopes.

Chris Renner, O.D.

Optometrist, Low-Vision Specialist
Baileys Crossroads, Virginia

Signs of a disease are actually “findings upon an examination.”  Signs are what a doctor sees.  Symptoms are what ails the patient.  Both signs and symptoms should match up to make a diagnosis.  Sometimes there is a disconnect, that is, signs are present, but no symptoms, etc.

Signs of macular degeneration include drusen, pigment changes, serous fluid and blood;

• Drusen – either “hard” or “soft”
  • Hard Drusen – fine well defined white spots in the retina
  • Soft Drusen – larger, lacier edged white spots

• Pigment Changes – either increased or decreased pigment

• Fluid – actual clear accumulation of fluid in the retina

• Blood – er, blood

Symptoms of Macular Degeneration include;  blurry vision, distortion and scotomas (dark/blind spots in the vision).

What Does This Mean? If you have symptoms of macular degeneration, and the symptoms are persistent, then I’d recommend your eye doctor examine you.  If your doctor examines you and see “signs” of macular degeneration, then a fluorescein angiogram might be ordered to help confirm the diagnosis.  Not everyone will insist on a fluorescein angiogram.

A fluorescein angiogram will demonstrate areas of degeneration (defects in the RPE layer of the retina) and can also confirm suspicious area of neovascularization; leading to the diagnosis of “wet” macular degeneration.

Sometimes, patients have no complaints, but a doctor notices drusen in the retina.  Not all drusen are associated with macular degeneration.  Some drusen are normal for patients.  Taking into account the patient’s age, vision and lack of symptoms, it is likely that these “drusen” are normal and not associated with disease.  The fluorescein should be normal.

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
Fairfax, Virginia

Avastin® is useful for a variety of eye conditions;  it is principally used to treat wet macular degeneration and is becoming a popular option to treat diabetic macular edema.  On occasion, Avastin has also been useful, in my practice, to treat patients with proliferative diabetic retinopathy.

VEGF (Vascular Endothelial Growth Factor) also causes abnormal blood vessels to grow in cases of “wet” macular degeneration and … proliferative diabetic retinopathy.

Proliferative Diabetic Retinopathy (PDR) is defined by the presence of abnormal “neovascularization.”  These are abnormal proliferations of blood vessels that grow inside the eye.  In patients with diabetic retinopathy, the VEGF is produced in response retinal ischemia; retinal demand for oxygen exceeds the supply due to poor blood supply.  VEGF then causes neovascularization to develop.  This neovascularization can cause blindness by causing retinal detachments or neovascular glaucoma.

The  traditional treatment for proliferative diabetic retinopathy has been laser photocoagulation.  The laser treatment, called pan-retinal photocoagulation (PRP), has been the treatment of choice for years.  The PRP destroys enough tissue so that the available blood supply is adequate to meet the oxygen requirements of the tissue.  When this occurs the “ischemia” is cured, VEGF is no longer produced and the proliferative retinopathy becomes stable.

Occasionally, I have  patients that do not respond well, or completely, to pan-retinal photocoagulation.  Lately, on select cases, I have used Avastin as an alternative to pan-retinal photocoagulation for the treatment of proliferative diabetic retinopathy.

So far the treatment works well.  The neovascular tissue regresses quickly and I recheck patients every 4-6 weeks.  The injections do need to be repeated.

What Does This Mean? Pan-retinal Photocoagulation has been the gold-standard for the treatment of proliferative diabetic retinopathy.  The PRP can decrease light to dark adapatation, that is, it takes awhile to get used to light when coming out of a movie theater.  It is a difficult procedure to perform, but has been very effective over the years.  I consider it a good “fix.”

An alternative therapy is welcomed for two reasons.  Avastin injections are certainly easier to perform and seem not too affect the vision.  Avastin also treats the disease by a different mechanism and may increase the chances of achieving stability.  On the other hand, Avastin does NOT change the relative ischemia in the retina, that is, the oxygen demand is still greater than oxygen supply.  It may be less of a permanent “fix.”

“Randy”

Randall V. Wong, M.D.
Retina Specialist, Ophthalmologist
Fairfax, Virginia

There are many lasers and many ways to use lasers in eye surgery.  I am asked all the time if I perform “laser surgery,” but I know what they are asking.  While I do perform laser surgery for diabetic retinopathy, and (not so much anymore) macular degeneration, they are really asking if I perform laser vision correction eye surgery.  No, I don’t.

There are at least 5 different areas of ophthalmology using at least 6 different laser to perform “laser surgery.”

Laser Vision Correction is a laser procedure using an Excimer laser.  Principally, it reshapes the cornea to refocus light, allowing less dependence upon glasses.  Okay, it reshapes the cornea so people are less near-sighted.  Most of the time contact lenses and glasses are no longer needed.  People see well, assuming the retina/macula is normal.  There is limited use for far-sighted individuals.

Glaucoma laser surgery is performed for two reasons, and uses two different lasers.  In several types of glaucoma (e.g. open angle glaucoma, pigment dispersion), laser burns, using an argon laser, are placed on the trabecular meshwork to cause a reduction in eye pressure.  The trabecular meshwork is part of the drainage portion of the eye.  A diode laser can be used to perform a similar procedure as well.

In angle closure, or narrow angle, glaucoma, a ND:Yag laser is utilized to “cut” a hole in the iris (see below).  This hole, aka iridectomy, creates an alterate pathway for the intraocular fluid to leave the eye.

A similar Yag laser can be used for another glaucoma procedure called cyclophotocoagulation which reduces eye pressure by destroying the ciliary body, the tissue that makes intraocular fluid.

Nd:Yag laser is also used to fix “after-cataracts.”  When the natural cataract is removed from the eye, it is replaced by a crystal clear implant.  The implant rests in a clear sac that used to hold the cataract.  This tissue is similar to “Saran” wrap and commonly gets cloudy.  This cloudy tissue causes decreased vision in much the same way the original cataract caused problems.  Using the Nd:Yag laser, a cutting laser, a small hole is cut in this tissue allowing vision to be restored.

Diabetic retinopathy is common treated with laser photocoagulation.  Most of the time an argon laser is used for either treating macular edema or proliferative diabetic retinopathy.  An argon laser transfers heat and is a type of thermal laser treatment.  Laser treatment for diabetic macular edema is directed at microaneurysms.  Theoretically, the heat from the laser causes these tiny outpouchings along the vessel walls to scar over and stop leaking.  The same laser is used to perform panretinal photocoagulation (PRP) for cases of proliferative diabetic retinopathy.

Photodynamic Therapy (PDT) is a type of treatment for wet macular degeneration.  It was introduced as a “cold” laser.  A drug, Verteporfin,  is infused into the body via an intravenous line.  The drug accumulates in the abnormal blood vessels gathered underneath the retina.  The PDT laser is then used to convert the accumulated Verteporfin into a substance toxic to the neovascular tissue.  This treatment is still used for wet macular degeneration.

CO2 and Erbium lasers are also used in cosmetic skin laser surgery and is included here as our oculoplastic colleagues use these in their practice.

What Does This Mean? It’s not a coincidence that there are so many lasers used in ophthalmology.    Lasers (Light Amplification by Stimulated Emission of Radiation) are basically light beams.  As the structures of the eye are directly visible, i.e. you can see them, and can be “reached” by light, or laser.  Unlike other fields of medicine, we enjoy direct visualization of the structures/tissues we are treating.

So,  “Do I perform laser eye surgery?  Yes, I do.”

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
Fairfax, Virginia

A couple of months ago, I examined a new patient who had been complaining of decreased vision, and distortion, in the right eye for about 2 months.  His vision was 20/200 in the right eye.  After examination, I recommended  Avastin® treatment for his wet macular degeneration.  This is his account of the injection and the weeks after.

Saturday, 12/5 I was administered the shot of Avastin at about 12:49 pm. I was first given about 4 Q-tips of topical anesthetic. The Avastin was then administered. I felt no pain when the needle entered, but I felt a not-too-s pressure. Soon thereafter, I suspect when the drug was “pushed’ out of the syringe, I did feel slight pain for about 1 second or so.. The fact that I felt some pain worried me, more that the slight pain itself, likely because of where and how I felt it….a NEEDLE in my EYE, knowing I couldn’t move. The pain disappeared immediately after about 1 second. After the needle was removed, I felt no pain whatsoever. Soon after leaving the office, I felt a significant irritation in my eye, similar to what one would experience with a more than mild seasonal allergy. There was slight burning, but NOTHING what one might say would approximate any kind of pain, For the next few hours it persisted, then it went away. Perhaps it was because of a post-procedure antibiotic. The rest of the day my eye was irritated, but nothing more that the feeling one might have when the eye is scratched when taking out a contact. I did feel some slight pressure/swelling of the eye afterwards, throughout the day, but, again, no pain. I went to bed at about 11:45 pm on Sat.

Sunday, 12/6 I woke up on Sunday at about 8:30, My eye felt normal. I did not have a contact lens in the subject eye since the night of Friday, 12/4. I looked in the mirror, and it visually appeared to look normal. I got my act together, then went downstairs. I closed my good eye, to see how the subject eye was performing. Without considering the distortion issue which brought me to Dr. Wong, the “clarity” of vision in that eye “seemed”, and “seems”, noticeably improved, without my contact in. Lines seem more defined and crisper.

As to the distortion, my sense is that it is already improved, although it is still definitely present. I note, however, that it seems less “bothersome” to me on a minute-by-minute basis. I am writing this shortly thereafter…at 9:36 a.m….only 21 hours after the procedure that administered the drug. It is possible that my perception is psychological, or that it is difficult to judge comparatively since my eye was irritated until I went to bed last night, but my “sense” is that the distortion is actually improved from the starting point. Overall I would rate my vision in the subject eye as already being better than before I underwent the procedure.

Monday, 12/7 Upon wakening this morning, and for 2 hours thereafter, I noticed no change in my vision from Sunday.

Tuesday, 12/8 I noticed no change in my vision an hour after my 6:00 a.m wake up

Wednesday 12/9 – 12/13 No discernable difference in my vision

Sunday 12/13 My impression is that there seems to be some slight improvement in the distortion, but it is not possible to accurately define.

Wednesday 12/15 I notice that I am able to read large type better than before, but small type is not possible. The distortion seems the same since yesterday

Saturday 12/19 In the shower this morning, I had the strong impression that my distortion is much better. There is still distortion, but it seems much less significant than before. When I close my left eye, there is what I feel is excellent clarity, but still some distortion.

Friday 1/1 I noticed in the shower that my distortion seems improved again. Things don’t seem as slanted with my right eye, as compared to my left eye (with right eye shut).

Friday 1/8 My impression is that the distortion is improved again, but it’s hard to explain “how”. I suppose, it’s just a bit less severe.

Wed 1/13 No discernible change…………

_______________________________________

Sat 1/23

Got another shot yesterday. They left the anesthetic on longer before the shot. I had no pain during the shot, but it was pretty uncomfortable. No big deal. The shot was quick. Had burning and watery eye for next 3 hours, then much better. Woke up this morning, and for the first ½ hour I forgot that I even had a shot yesterday.

Put the contact lens in about 9:30 am. All systems are go. Eye feels a touch tender, but a total non-issue.

I notice no change in my vision from before the shot yesterday.

****************************

What Does This Mean? The second shot was administered last Friday.  Vision had improved from 20/200 to 20/40 in just six weeks!  In all the literature, you never read anything from the patient’s perspective.  I find it interesting that my patient noted changes in the vision almost immediately and that these changes continued for the first month.  A third injection is planned in another 6 weeks.  I suspect that the vision will continue to improve, especially the distortion, based on the location of the neovascular tissue;  it is just to the side of the macula.  Once the nevascular tissue has regressed, additional injections may be needed for “maintenance.”

“Randy”

Randall V. Wong, M.D.
Ophthalmologist, Retina Specialist
Fairfax, Virginia