Cataract Surgery and Lens Implant Expert Witness

posted in: Ocular Surgery

Cataract surgery is one of the most commonly performed surgical procedures in the United States.  Every year millions of patients benefit from having cataract surgery.  An expert witness for cataract and lens implant surgery may be utilized to review indications, the process, and potential complications of cataract surgery.

A cataract occurs when the naturally clear lens of the eye becomes cloudy or opaque.  Light rays that normally travel through a clear lens are impeded with a cataract.  As the lens becomes progressively cloudy, vision becomes progressively worse.  Cataracts develop as a natural result of the aging process, and they are often associated with exposure to sunlight.  Certain medications, most notably steroids, and other eye illnesses such as iritis, may also cause cataracts.  If untreated, cataracts may cause potentially reversible blindness.   Cataracts consist of the world’s leading cause of blindness.

Cataract surgery is considered when cataracts develop to the point when they impair the ability of a patient to function or cause vision threatening problems, such as glaucoma.  Cataract surgery is usually an out-patient procedure and is generally considered to be safe and effective.  In cataract surgery the natural lens is removed and a clear artificial lens substituted.  The substituted lens is known as a lens implant.  Lens implants come in a variety of powers and a variety of styles.  The power of a lens implant is determined preoperatively by measuring the axial length of the eye by either laser or ultrasound, and by measuring the curvatures of the front surface of the eye.  After removal of the cataract, the lens implant is usually positioned in the part of the eye known as the posterior chamber.  The posterior chamber has a lens capsule that holds the lens implant in position.  At the conclusion of cataract surgery, the incision is checked for proper closure and eyedrop medications are used postoperatively to prevent infection and facilitate healing.

Complications of Cataract Surgery

Fortunately, the vast majority of patients have visual improvement with successful cataract surgery.  Complications, although infrequent, mainly consist of infection, bleeding, retinal edema, retinal detachment, and issues relating to the lens implant. Complications can range in severity from mild and transient to permanent and severe.

Some of the more common and significant complications of cataract surgery:

  • Infection.
    Many post-operative infections are mild and are treated with antibiotic eyedrops.  An infection that involves the interior of the eye is known as endophthalmitis and can cause rapid and permanent loss of vision.  It is important to detect endophthalmitis early and treat it aggressively.
  • Iritis.
    Most cataract surgery patient have inflammation in the front portion of the eye.  This condition is known as iritis and is treated with anti-inflammatory eyedrops.
  • Rupture of the lens capsule.
    During cataract surgery the lens capsule may be damaged.  If so, the operating surgeon may not implant a lens that is normally placed in the capsule.  Instead, an alternative lens (backup lens) may be used.  Rupture of the lens capsule may allow a gelatinous fluid located in the center of the eye to prolapse through the open lens capsule.  This condition is known as vitreous loss.  Vitreous loss is often accompanied by secondary complications that include swelling of the retina (macular edema), retinal tear, or retinal detachment.  Secondary complications of cataract surgery may be treated by a variety of medications, laser surgery, or conventional surgery.
  • Dropped cataract.
    A rare but dreaded complication of cataract surgery occurs when the lens capsule ruptures during surgery and the cataract falls through the opening of lens capsule.  When this happens, the patient is often referred to a retina specialist for a specialized type of cataract surgery.
  • Lens implant.
    The traditional lens implant is a monofocal lens that is designed to focus at one particular distance.  A multifocal lens (Rezoom, Restore) has concentric rings that permit multiple focal points.  The theoretical advantage of multifocal lenses is to minimize dependence on glasses for tasks that require different focusing distances.  The efficacy of multifocal lenses depends on pupil size, brain adjustment, presence of astigmatism, underlying retinal pathology, and visual needs of a patient.  A significant number of patients with multifocal lenses complain of nighttime glare or lack of clear vision. Another type of lens is an accommodative lens (Crystalens).  The accommodative lens is flexible to allow muscle contraction within the eye to flex the lens and adjust focusing for various distances.  Another type of lens is known as light-adjustable.  A light-adjustable lens patented by Michael Reynard, M.D. (U.S. patent 6,520.955) consists of a special material placed within the capsule of the natural lens.  A specific wavelength of light adjusts the power of the lens after surgery to give a precise focus.  The natural flexibility of the lens material within the lens capsule provides focusing ability at various distances.

Cases in Point

Dr. Reynard was retained as an expert to assess standard of care for cataract surgery and visual damages in a patient who mistakenly had placement of an incorrect lens implant at the time of cataract surgery.

Dr. Reynard was retained as an expert to evaluate standard of care for a surgical case involving instrument failure during cataract surgery.

Dr. Reynard was retained as an expert to evaluate allegations of patent infringement for a multifocal lens implant.  Dr. Reynard has many patents regarding surgical instruments for eye surgery and a new surgical technique for cataract surgery with an advanced accommodative lens implant.

Dr. Reynard published an article in the Archives of Ophthalmology describing cataract surgery with lens implantation.

Dr. Reynard was retained as an expert to evaluate allegations of patent infringement regarding a case of a multifocal lens implant.

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