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Cataracts: The Eyes Have It

  • Wednesday / September 30, 2015
Cataracts-The-Eyes-Have-It

Cataracts: The Eyes Have It

I came to his office for an eye exam; and left with an uneasy feeling. Since having been diagnosed with Sarcoid, over 10 years ago, I’ve had to go for regular eye exams, along with regular lung exams. Usually pretty routine. But this eye exam was a tad different. When Dr Sergio Peneiras of Brighton Eye Care was done with his full exam, he started telling me my vision hadn’t changed since my last visit a year ago. I was flummoxed. It seemed to me, my vision had changed dramatically around December of 2014. Dr Peneiras then said, “it’s probably due to your cataracts getting worse”. My WHAT? I had been to Dr Peneiras before, but certainly don’t remember him ever telling me I had cataracts! That’s one of those phrases you’d tend to remember.

We talked a little more, he said it could be from my Type II Diabetes, but I was way too young to have cataracts already. Dr Peneiras said, “… When you feel your cataracts are hindering your vision too much, I can recommend an ophthalmologist”. To which I answered, “I work at a computer all day, it’s already compromising my vision”. So he recommended and wrote a prescription for Dr Douglas Grayson of Omni Eye Service in Islen, NJ.

Fast forward to yesterday; Tuesday, September 29th at the Omni Eye Service office.

I left my apartment with plenty of time to spare. Only problem — all the PDF forms that I so meticulously filled out on my computer and printed —  I left home! No time to turn back! Got to the office about ten minutes before my 12-noon appointment time. Just one minor hitch, there were about twenty people ahead of me! And that’s no exaggeration. All told, I spent four hours in that place! I sat for an hour and a half before being brought back to be seen by the first doctor: Dr Nadine Herman.

I really liked Dr Herman! She had a great bedside manner, really listened, was thorough in her examination and questioning. By the end of our examination, she already earned my coveted title of “Advocate”. The eye exams she put me through, were involved, indepth, and revealing — figuratively and literally. She was examining my cataracts with exacting care. This was the process to see the severity of the cataracts and measure me for the corrective lenses, Dr Grayson will surgically “install” in two separate surgeries.

When Dr Herman was done, she explained every detail of the two procedures, the time it would take each eye to heal, and most surprising of all, the actual type of cataracts I had. Of course, with my batting record, my cataracts would not be your run of the mill age-related cataracts — oh no! My cataracts were “steroid-induced cataracts or posterior subcapsular cataracts (PSC)”. Yes, my cataracts came from the very drugs used to battle my Sarcoidosis — prednisone! Yippee! WTF? I not only have my very own personal autoimmune disease, I have a new disease caused by one of the only drugs used to treat said malady! Bonus points!

For those who are looking for details on Steroid-induced cataracts — here you go:
The Crystalline Lens

The Crystalline Lens

The crystalline lens is a natural lens located in the interior of the eye, behind the iris, able to focus images of the external world onto the retina depending on their distance. The crystalline lens is a biconvex lens of variable focusing power, namely a lens able to modify its optical (or focusingpower by changing its shape, a phenomenon known as accommodation. The ability of the crystalline lens to modify its shape (curvature) – and hence its optical (or dioptric) power – depends on the work of the ciliary body, an eye structure which is connected to the crystalline lens through a system of fibrils, called zonular fibers, and that works as a real muscle.

The crystalline lens is composed of three different layers:
1) an external membrane called capsule
2) the lens itself – called central nucleus
3) and an intermediate layer called cortex, situated between the central nucleus and the capsule.

At a young age and in the absence of pathologies, the crystalline lens is an elastic and perfectly transparent tissue; the loss of elasticity gives rise to presbyopia (the inability to focus on near objects), whereas the loss of transparency, which is caused by a process of opacification of the lens, gives rise to an eye condition known as cataract.

The opacification of the crystalline lens makes vision cloudy and, depending on the seriousness and localization of the opacification, the resulting visual impairment may be quite significant. Cataract formation is very common in older age (age-related cataract), but there are several other factors that can determine the formation of different types of cataract, such as 1) congenital cataract, already present at birth, 2) secondary cataract, caused by pre-existing pathologies – affecting the eyes (e.g. glaucoma, uveitis etc.) or the whole organism (e.g. diabetes), 3) cataract related to severe nearsightedness, due to pre-existent pathological myopia, 4) traumatic cataract, such as that deriving from eye injury or surgery, 5) radiation or phototoxic cataract, which follows prolonged exposures to strong sunlight or UV-radiations (e.g. solar lamps, laboratory instruments etc.) without adequate protection, and 6) drug-induced cataract (e.g. steroids-induced cataract). Family history plays also a very important role in the development of cataract.

Steroid-induced Cataract or Posterior Subcapsular Cataract (PSC)

Steroid-induced Cataract or Posterior Subcapsular Cataract (PSC)

Among drug-induced cataractssteroid-induced cataract assumes a very relevant importance due to the wide use of steroids (also known as corticosteroids or glucocorticosteroids) in medicine.

Steroid-induced cataract differs from the other types of cataract for its origin, peculiar anatomical location and aspect. With regards to its anatomical location, steroid-induced cataract formation occurs always in the posterior cortex, just within the posterior capsule, and for this reason it is called a posterior subcapsular cataract (PSC). PSC presents a characteristically irregular shape and a dishomogeneous structure consisting of whitish-yellowish opaque granules interspersed with very tiny vacuoles. PSC usually develops in both eyes at the same time.

Corticosteroids (Also Known As Glucocorticoids Or Steroids)

Corticosteroids (Also Known As Glucocorticoids Or Steroids)

Corticosteroids (or glucocorticoids) belong to the wide class of chemical compounds called steroids, which are ubiquitous in animals and plants, where they have very important biological functions. In animals, steroids can be classified into five categories: Estrogensprogestagensandrogensmineralcorticoids and glucocorticoids. All corticosteroids can be produced in different tissues of the body and can present the most various functions. Every single compound is produced by a specific body compartment (tissue, organ) and acts in a specific way on – and then in – specific cells called target cells, which can be near or far from the production site. Once entered in a cell, steroids can trigger different cellular mechanisms; most of these mechanisms act very often on the regulation of DNA.

The most common glucocorticoid in nature is cortisol (or hydrocortisone), from which derive cortisone and corticosterone. Glucocorticoids are powerful anti-inflammatory and immunosuppressive agents and are the most widely used drugs to treat inflammations – also ocular inflammations – and prevent rejections after organ transplantation. The usefulness of glucocorticoids in medicine brought pharmaceutical industries to synthesize new molecules with different functional groups and hence different properties.

Corticosteroids And Direct/Indirect Undesired Effects On Eye Health

Corticosteroids And Direct/Indirect Undesired Effects On Eye Health

The use of glucocorticoids presents different contraindications and adverse reactions that may affect eyes directly or indirectly, such as for example the onset of diabetes, a metabolic disorder that can have very serious consequences on the retina, and the enhancement of the intraocular pressure (IOP) that can cause glaucoma, an eye pathology that can cause extremely serious damages to the optic nerve and hence vision. Other side effects deriving from the use of glucocorticoids are the reactivation of the Herpes simplex virus and the reduction of the healing process of the cornea after damage or refractive surgery. The most common and known side effect due to the use of corticosteroids is the development of posterior subcapsular cataract (PSC): Cortisondesametason and prednisone are the most common drugs that, among others, induce PSC formation.

Corticosteroids And The Induction Of Posterior Subcapsular Cataract (PSC)

Corticosteroids And The Induction Of Posterior Subcapsular Cataract (PSC)

The correlation between the prolonged use of corticosteroids and PSC formation is known since 1960. Corticosteroids are widely used drugs and they are real life-savers in many situations, such as for example bronchial asthma and “anaphylactic shock”, to contrast serious inflammations (cortisone is the most commonly used drug for rheumatoid arthritis) and to inhibit rejections in patients who underwent organ transplantation.

Several studies have shown that cataract formation due to the use of corticosteroid presents a dose-effect: The higher the dosage, the higher is the percentage of cataract formation. The effect of PSC formation on children is faster and at a lower dosage. According to many researchers, besides dose-effect, individual susceptibility is also a very important factor, most probably due to genetic variability. In any case, dose-effect of corticosteroids is a problem to which doctors must pay great attention when they prescribe treatments based on steroids to their patients, above all if the treatment is long-term.

Given the existence of different individual susceptibility to the same drug and different susceptibility of the same individual to different drugs, it is not possible to foresee if and when steroids administration will give rise to cataract formation, hence the best thing to do for a patient receiving steroid treatment is to undergo careful eye examinations regularly, in order to monitor the state of health of the crystalline lens over time.

Today the use of steroids is strongly increasing, hence we expect an increase of PCS.

Mechanisms Of Cataract Formation

Mechanisms Of Cataract Formation

Until today there has been a great difficulty in creating an experimental model (both animal and in vitro) to study the mechanisms by which corticosteroids induce cataract formation, hence research carried out so far in this field has given uncertain results, unable to suggest a universally recognized model valid for the pursuit of methods, drugs and protocols to be used as prophylaxis for PSC formation in case of long-term use of corticosteroids.

Several different theories have been proposed to explain cataract formation in general and PSC formation in particular. We resume here, in a very simplified way, the most important theories.

The universal mechanism of cataract formation suggests that oxidative, osmotic or metabolic stress causes alterations of the lens proteins, which then interact in a casual and disordered way, giving rise to protein aggregates that form sovramolecular complexes able to scatter or block the light rays that cross the crystalline lens.

According to the theory of metabolic disturbances, glucocorticoids alter cellular metabolism leading to an inadequate energy production and to a malfunctioning of many cellular mechanisms, including antioxidant mechanisms that should protect the cell from aging, thus producing damaging effects on the synthesis of DNA and cell growth.

According to the theory of osmotic failure, glucocorticoids lead to ionic imbalance and hence to an alteration of the lens osmotic pressure – the ability to attract water in its inside – that causes water accumulation in the lens tissue, determining variations of the refractive index of the medium and hence focusing problems.

According to the theory of aberrant lens cell behavior, corticosteroids induce PSC acting indirectly, not on the lens cells but on the cells of the ciliary body, leading them to produce an abnormal aqueous humor (the transparent liquid that normally bathes and nourishes the crystalline) containing altered concentrations of the molecules responsible for the growth and keeping of the normal cell architecture of the crystalline lens; this variation modifies the spatial organization of the cells of the lens, causing an interference with the path of the light across the crystalline lens.

Symptoms Of Cataracts

Symptoms Of Cataracts

The most common symptoms of all types of cataracts include:

  • Blurred or cloudy vision in absence of ocular pain,
  • Increased sensitivity to light, dazzling,
  • Poor night vision,
  • Diplopia (double vision),
  • Need of brighter light for reading,
  • Altered color perception (colors may appear faded or yellowish),
  • Loss of contrast sensitivity,
  • Blindness.

Cataract may develop at variable speed in different persons. Usually, contrarily to the more common age-related cataract, steroid-induced cataract may develop in younger people, in both eyes simultaneously, and may progresses quite rapidly.

When Cataract Surgery Is Necessary

When Cataract Surgery Is Necessary

Steroid-induced cataract can progress quite rapidly and cataract surgery should be performed when the condition becomes troublesome and the person affected feels the need to get rid of it in order to re-establish a clear vision, especially if vision is so blurry to make it difficult if not dangerous to carry out normal daily activities such as going downstairs or driving. It is very important not to wait too long before performing cataract surgery, because in this case the crystalline lens becomes particularly hard and this may give rise to higher risks of complications during the surgical procedure.

Prevention Of Cataract And The Importance Of The Use Of UV Protection

Prevention Of Cataract And The Importance Of The Use Of UV Protection

Unfortunately, there are no drugs, eye drops, eye exercises or eyeglasses that can stop or slow down the process of the crystalline lens opacification. Today, the only cure against cataract is cataract surgery, a safe, fast and non-painful routinary surgical procedure that consists in the removal of the opacified crystalline lens and its replacement with a perfectly transparent artificial lens.

The use of sunglasses or clip-on lenses with protection against UV can surely help protect your eyes from UV-light and prevent, or at least delay, cataract formation and also the development of other important ocular pathologies such as maculopathies.

Cataract Surgery: Phacoemulsification

Cataract Surgery: Phacoemulsification

The most advanced cataract surgery procedure available nowadays is called phacoemulsification, which consists in the removal of the opacified crystalline lens and its substitution with a biocompatible artificial lens, called intraocular lens (IOL). Phacoemulsification is a very sophisticated technique that uses ultrasounds to break and eliminate the most central portion of the opacified crystalline lens. The external portion of the crystalline lens, called posterior capsule, is left untouched and works as support for the implant of the new artificial crystalline.

Phacoemulsification is performed in an outpatient modality after local anesthesia and it lasts a few minutes; its performing is minimally invasive, absolutely painless and presents a short post-surgical period (a few days) with no particular discomfort.

Benefits And Possible Risks Of Cataract Surgery

Benefits And Possible Risks Of Cataract Surgery

Cataract surgery is a procedure that offers excellent results and nowadays benefits deriving from this technique are really consistent. Vision improves sensibly in the majority of people who undergo this procedure, unless there are serious pre-existing problems affecting the cornea, the retina or the optic nerve.

Very serious complications, such to limit or put vision in danger, are extremely rare; however before undergoing cataract surgery it is very important to talk with your eye doctor about advantages and possible complications of this procedure.

Secondary Cataract (Capsular Fibrosis) And Posterior Capsulotomy

Secondary Cataract (Capsular Fibrosis) And Posterior Capsulotomy

In most cases, months or years after cataract surgery, the posterior capsule(the posterior part of the external membrane of the crystalline lens, called capsule, which hosts the crystalline lens) can also undergo a process of fibrosis and opacification, making vision blurry again. This condition is called secondary cataract (the more precise medical term is capsular fibrosis) and has to be treated with a second short procedure called posterior capsulotomy, a non-invasive laser treatment that lasts a few seconds and is absolutely painless and discomfortless in its post-operative period.

Now that you know more than you might ever — or never —  wanted to know about Steroid-induced cataracts; my story continues

Hours later, once Dr Herman was done, I had to then meet with Dr Grayson. Even though he is the surgeon doing both procedures on October 30 and November 13, he felt more like a seedy car salesman trying to upsell me on the more costly options of lens replacement. If I could, I’d have Dr Herman do the procedure; but she’s not the ocular maestro — Dr Grayson is. Sometimes you do have to put aside feelings to “get the job done” by the best person for that job. Once done with him I was sent to scheduling to set up the two procedures. If all goes well, and there are no hiccups, my eyesight will be back to normal — or as normal as it can be. I really can’t wait!

The single vision lenses I selected, as well as the surgery and follow up visits, will all be completely covered by my Horizon NJ Health insurance. My single vision lens will also correct my nearsightedness, but not any astigmatism that I have. So I will still need glasses to correct my astigmatism and for reading; which is fine by me. But if I wanted to spend $4,000.00 – $5,000.00 + out of my own pocket,  I could get the deluxe package, which would include bifocal lenses, and insertion via laser surgery. Admittedly, the laser would be the way to go, since it helps speed up the healing process, but doctors have been doing the slice and dice method for a long time. It will mean a few more days/weeks of healing, antibiotic, and steroid eye drops; but is still worth the price of admission — FREE! Plus, if my eyesight does change, it’s more easily augmented with new glasses. So I’m happy with my choice. Now all I have to do is wait to have it done. And honestly, I will be happy to have clear vision once again!

This whole process was an eye opener — no pun intended — on multiple levels. I learned that all cataracts are not created equal, or for that matter, in the same way. And even though my cataracts are not “directly” caused by my Sarcoid, indirectly they are! Aren’t we having fun!

File Under:  Sarcoid: The disease that keeps on giving!

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Joe Streno

artist . musician . photographer . retired apple computer consultant . residing on planet earth with his two cats rudie, & rocco & living to tell tales about it

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