About Cataract

A cataract is a clouding of the normally clear lens of the eye.  The eye’s natural crystalline lens refracts light rays that come into the eye, to help us see. This lens should be clear, but in cataracts it becomes cloudy and affects vision. Clouded vision caused by cataracts can make it more difficult to read, drive a car (especially at night) or see the expression on a friend’s face. Generally, things look blurry and less colorful with a cataract.

Most cataracts are related to aging, develop slowly and don’t disturb the eyesight early on. But with time, cataracts will eventually interfere with vision.

Common Types of cataract

Nuclear cataract is the most common type. It develops deep in the central zone of the lens. Nuclear cataracts usually are associated with aging.

Cortical cataract refers to white opacities, or cloudy areas, that develop in the lens cortex, which is the peripheral (outside) edge of the lens. People with diabetes are at risk of developing cortical cataracts.

Subcapsular cataract occurs at the back of the lens. People with diabetes or those taking high doses of steroid medications have a greater risk of developing subcapsular cataract. People who have extreme nearsightedness, and/or retinitis pigmentosa may also develop this type of cataract. Subcapsular cataracts can develop rapidly and symptoms can become noticeable within months.

Posterior polar cataracts are characterized by well-demarcated white opacities in the center of the posterior capsule. These opacities often project forward as cylinders penetrating into the posterior lens cortex. This type is typically congenital and autosomal dominantly inherited.

Traumatic cataract develops after penetrating eye injuries, as well as after electrocution, chemical burns and exposure to radiation.

Risk Factors

Aging is the most common cause of cataract development. Other risk factors include:

  • Certain medical problems, such as diabetes, elevated blood sugar
  • Steroid use (oral, IV, or inhaled)
  • Ultraviolet exposure
  • Smoking
  • Ocular diseases such as Retinitis Pigmentosa, Uveitis
  • Ocular Trauma
  • Genetic predisposition
  • Previous eye surgery


Visual symptoms associated with cataracts include:

  • Blurred, clouded vision (distant or near)
  • Double vision when looking with just one eye
  • Halos or streaks around lights, difficulty seeing in the presence of bright lights, difficulty while driving
  • Poor night vision
  • Poor vision in low light situations
  • Fading or yellowing of colors
  • Frequent changes in eyeglass prescription (increasing nearsightedness and decreasing farsightedness)

Cataract Management

Cataracts can’t be treated with lasers or medication. Surgery is still the only treatment option. During surgery the cloudy lens is removed and replaced with a clear, manmade intraocular lens (IOL). There are multiple types of IOLs, including monofocal, multifocal, accommodative, and astigmatism-correcting lenses. The objective of all IOLs is to improve vision and limit dependency upon spectacles or contact lenses.

Cataract surgery is one of the most common and reliable operations. Each year, more than a million people have their vision improved through cataract surgery.

Now the clear-cornea technique makes the procedure even safer than before and makes recovery quicker.

The clear-cornea technique offers many benefits that can help the patient get back to normal activities quickly. Those include:

  • Less time in the operating room.
  • Painless surgery without needles, stitches or patches.
  • Clearer vision as early as the same day of surgery.
  • Faster healing of the incision.
  • Quicker return to usual activities in days rather than weeks.

Since 2012, our team has been using the innovative femtosecond laser technology in cataract surgery, aside from refractive surgery. The LenSx technology uses an automated laser mechanism to replace the three main manual steps of the procedure: corneal incision, capsulotomy and lens fragmentation.

Preoperative Examination

Like any other operation, cataract surgery requires a thorough eye examination. We carefully evaluate the entire eye, starting from the anterior segment: cornea, iris, lens and moving to the posterior segment: vitreous body, macula, vessels and optic nerve.

The examination includes the following measurements:

  1. Health history: it is important to mention all your medical issues and the medicine you are taking. That includes over-the-counter medicine such as aspirin.
  2. Visual acuity.
  3. Intraocular pressure.
  4. Axial length measurement.
  5. Corneal refractive power (corneal curvature).
  6. Endothelial cell count.
  7. Anterior chamber depth.
  8. PAM/RAM testing: to determine the potential visual acuity after the procedure in cases where a retinal disease exists.
  9. Biomicroscopic examination of the anterior and posterior segment of the eye.

The axial length and the curvature of the cornea determine the power of the IOL for each individual.

Innovation and Experience

Dr Kanellopoulos has been a pioneer surgeon in small incision laser cataract surgery. He has been one of the initial surgeon-investigators using Nanosecond laser for cataract surgery (1998) and the investigative supervisor for 25 international laser cataract surgery centers, that reported the initial outcomes of this fascinating procedure several years ago. Within this study, he became in 1999 the first surgeon worldwide to ‘’break’’ the 2mm incision size barrier that existed at the time for a cataract procedure and intraocular lens implantation. He has presented the excellent and promising clinical results with laser cataract surgery worldwide, and has published this innovative work in dozens of peer-reviewed journals.

Our team uses state-of-the-art diagnostic and treatment technologies, including the LenSx femtosecond laser since 2012.

Today’s advanced technology provides multiple types of intraocular lenses. The majority of patients chooses monofocal lenses to correct the distant vision and need to wear glasses for near and intermediate work. In 60% of our cases we use Toric monofocal lenses to correct nearsightedness or farsightedness and astigmatism as well (a world record in Greece since 2006).

There are options of iris-fixated and scleral-fixated lenses in cases of insufficient capsular support.

Multifocal or accommodative lenses offer a new alternative for those desiring to see objects clearly at multiple distances without glasses.

Risks and Complications

Cataract procedure is not only the most common intraocular intervention, but may well be the most common procedure performed annually. Modern cataract extraction surgery is relatively safe with low incidence of complications, considering the large overall number of procedures performed.

Perioperative complications encountered with cataract extraction surgery can be divided into intraoperative and postoperative. Intraoperative complications include posterior capsule rupture, with or without vitreous loss, loss of all or part of the lens nucleus, iris trauma and damage, Descemet’s membrane detachment, wound leak, and suprachoroidal hemorrhage.

The postoperative group can be further subdivided into early and late. Early postoperative complications include pupillary block, hyphema, elevation of the intraocular pressure associated with the use of viscoelastic substances, persistent uveitis (with or without hypopyon), and endophthalmitis (infection). Late postoperative complications include intraocular lens malposition, secondary glaucoma, cystoid macular edema, retinal detachment, and pseudophakic bullous keratopathy.

When complications do occur, most are minor and can be successfully treated medically or with additional surgery.

High postoperative spherical refractive error can be another unpleasant surprise. This is more common in high myopes and hyperopes, and in patients who have had refractive surgery or cornea transplantation procedures. The options for these eyes include exchanging the intraocular lens, piggybacking an IOL or performing a refractive procedure.

LASIK may also be a reasonable option for patients with stable refractions and good capsular support and intraocular lens centration.

Posterior Capsular Opacification (“ Secondary Cataract ”)

The most common postoperative complication is posterior capsular opacification. This is not an actual IOL complication; rather, PCO is caused by residual, equatorial lens epithelial cells after cataract procedure. These cells migrate and coalesce at the center of the posterior capsule, resulting in significant visual symptoms.

Although some people call PCO a “secondary cataract,” it really is not a cataract. Once a cataract is removed, it does not come back.

Symptomatic posterior capsular opacification is generally easily treated with Nanosecond: YAG laser capsulotomy in the examination room. The laser removes the hazy posterior capsule without making an incision or “touching” the eye and it is completed in a matter of minutes.

The night before the procedure

Don’t eat or drink anything after midnight the night before your surgery. This includes water, coffee, chewing gum, and mints. If you have been told to continue your daily medication, take it only with small sips of water. Make sure you follow any other instructions your doctor gives you.

The day of the procedure

Have someone drive you to and from the clinic. Plan to be there for about 1 to 2 hours. The procedure is brief but the medical personnel needs a little time to get you ready for surgery.

For your safety and effectiveness of the procedure, an anesthesiologist will be present to monitor your vital signs.

Just before surgery, your doctor will give you medicine that will relax you and keep you from feeling pain. You may sleep lightly.

Informed consent

On your consultation day, you will be provided with all the necessary information regarding the risks, benefits and possible outcomes of a cataract procedure. You will have the opportunity to ask and clarify any questions during this process in order to make an informed decision. Before proceeding with any operation, you will be asked to sign the informed consent form.

Post-operative instructions after Cataract procedure

Artificial tears (preservative-free)

One drop in the eyes, as often as needed, ten minutes after applying the medication drops. They contribute to eye moisturizing.

Eye drops Use

  • Always wash your hands before putting in the drops.
  • Shake the bottles thoroughly prior to each drop.
  • There is no preference as to which medication drop is applied first, just remember to wait 2-3 minutes between each drop.
  • You may experience a medicinal taste in the back of your throat after putting in drops, this is normal.
  • Eye drops are not applied during night time.
  • Be careful not to touch the eye with the bottle.
  • Keep eye drops in a cool place, away from heat, moisture and direct sunlight


  • It is very important to pay attention to your eyes hygiene for one week after the operation.
  • Avoid rubbing, bumping, or scratching your eyes.
  • A pair of eye shields is provided in your “post-operative care kit”. The shields are to be worn at night or during naps with the pointed part of the shield pointing towards the nose. A roll of tape is included in the kit to apply the shield for subsequent nights.
  • Do not swim/ work out for one week after the operation.
  • Do not rinse your eyes with water. Wash your hair leaning backwards keeping your eyes closed (as if it was done at the hairdresser’s).
  • Avoid facial cosmetics, makeup, mascara and colored contact lenses for one week after the operation.
  • Do not drive until you are confident with your vision.

Possible symptoms

  • foreign body sensation
  • pain
  •  blurred vision
  • itchiness
  • lacrimation
  • redness
  • eyelid swelling
  • sensitivity to light
  • headache

These are normal symptoms to expect after the procedure. Your eye drops, artificial tears, a painkiller and a good rest will help you through your recovery. 

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