Introduction
Cataracts are the most common cause of visual loss and blindness in the world. According to the American Society of Cataract and Refractive Surgery approximately 3 million Americans undergo cataract surgery each year. Most of these surgeries are performed without complications. Some patients do suffer significant complications.
Definitions
A cataract is a clouding of the natural lens in the eye. It is located behind the iris and the pupil.
There are 3 basic types of cataracts.
Nulearslorotic cataract is characterized by cloudiness in the center (nucleus) of the lens.
Cortical cataract is characterized by cloudiness in the periphery of the lens.
Posterior subcapsular cataract is characterized by cloudiness in the back of the lens.
Symptoms of cataracts include blurred or cloudy vision, sensitivity to bright lights, and glare to bright lights such as oncoming headlights at night.
Many factors are associated with cataract formation, including:
- Aging
- Ultraviolet radiation from sunlight and other sources
- Diabetes Mellitus
- Hypertension
- Obesity
- Smoking
- Long term use of corticosteroids
- Medication to reduce cholesterol (Statins)
- Previous eye inflammation
- Previous eye injury or trauma
- Previous eye surgery
- Hormone replacement therapy
- Significant Alcohol consumption
- Increased degree of Nearsightedness (Myopia)
- Family History
The Most Common Treatment of Cataracts
- Small incision cataract surgery by phacoemulsification (Ultrasound) with placement of posterior chamber intra-ocular lens.
- Laser Assisted Small incision Cataract Surgery by Phaco with placement of posterior chamber intraocular lens.
- Laser Assisted Small Incision Cataract Surgery by Phaco with placement of posterior chamber intraocular lens and Laser Relaxing Incision (LRI) for astigmatism.
The intraocular lens options include:
- Spherical intraocular lens which just corrects for distance vision spherical error.
- Toric lens which corrects for astigmatism.
- Presbyopic lens which corrects for distance and near vision. There are 2 types.
- Multifocal
- Accommodative
The Most Common Side Effects of Cataract Surgery Include:
- Undercorrection
- Overcorrection
- Induced Astigmatism
- Ocular Pain
- Endophthalmitis (Infection inside the eye)
- Swelling of the cornea or retina (macula)
- Bleeding
- Ischemic Optic Neuropathy (Lack of Blood Flow to the Optic Nerve)
- Retinal Detachment
- Vision Loss
Risks and complications
Permanent sight threatening complications include endophthalmitis (an infection of the intraocular cavities,) retinal detachment and ischemic optic neuropathy (infarction of the optic disc.)
Many risks and complications of cataract surgery include:
- Opacification of the Posterior Capsule (Thin clear membrane upon which the posterior chamber lens rest.
- Dislocated Intraocular lens- This occurs when the intraocular (IOL) is displaced out of its correct position. This can be as a result of a break in the posterior capsule during surgery or loose or missing zonules (suspensions attachment which hold the lens and capsular bag, which contains the IOL, in place.) It can also be as a result of the lens haptic being placed one in the bag and one out of the bag. Normally it takes about 3 months for an IOL to scar into position in the capsular bag.
- Ruptured Posterior Capsule with Vitreous Prolapse (Loss). This is where the posterior capsule is ruptured during surgery and the vitreous (Jell in the eye) comes forward into the anterior chamber or out of the eye completely. This can cause chronic inflammation and swelling of the retina (Macula edema) thus reducing visual acuity. This complication requires an anterior vitrectomy and a sulcus fixated IOL or a sewn in posterior chamber IOL or an anterior chamber IOL.
- Retained Lens Material
- Placement of incorrect IOL
- Improper alignment of Toric IOL
- UGH Syndrome
- Inflammation in the eye
- Glaucoma ( Increased pressure in the eye)
- Hyphema (Bleeding into the anterior chamber of the eye)
- UGH Syndrome is most often associated with placement of an anterior IOL
- Vitreous Hemorrhage
- Retinal Detachment
- Ptosis (Drooping of the upper eyelid)
Case Study
A 74 YEAR OLD WOMAN UNDERWENT CATARACT EXTRACTION BY PHACO-EMULSIFICATION. She suffered rupture of the posterior capsule with vitreous loss. She did undergo anterior vitrectomy and placement of posterior chamber IOL in the sulcus. The surgery had been on a Wednesday before a 4 day, 4th of July Holiday weekend. The patient was seen in follow-up the following day and had symptoms of floaters in the operative eye. The post –op exam was a normal post-op day 1 exam, with a vision of 20/60 pinholing to the 20/25.There was also slight swelling of the cornea. The post op day 1 also included a normal vitreous exam and a normal retinal exam to direct and indirect ophthalmology. The patient was put on Durezol, Vigamox and Ilevro eye drops with appropriate dosing intervals and asked to return to the office in 1 week. Unfortunately, the patient was not given the warning signs and symptoms of retinal detachment, which has an increased incidence after vitreous loss. The patient developed multiple flashes with what appeared to be a “curtain” hanging in the vision on day 2 post-op. The patient contacted her surgeon on day 3 post op. Her surgeon was enjoying time at the beach with his family. In that conversation the patient was asked if her vision was worse. The patient replied, “No, it was about the same.” The surgeon instructed the patient to continue her drops as directed and to follow-up at the appointed 1 week post-op. The patient did return on Post-op day 8 for her appointment. Her vision was count fingers at 1 foot in the operative eye and she was found to have a macula off retinal detachment in the operative eye. The vision in the eye was count fingers temporally at a distance of 1 foot. The patient did undergo retinal detachment surgery 2 days later by a retinal specialist. At one year after her retinal detachment repair the vision in the operated eye was very poor at the 20/400 level which constitutes legal blindness for that eye.
The breaches of the Standard of Care in the above case study were:
- The surgeon did not give the patient retinal detachment warning signs and symptoms despite the fact that the patient was at an increased risk for retinal detachment due to vitreous loss at the time of the original surgery, and
- The surgeon did not see the patient on an emergent basis when the vision for the patient was reported as unchanged in spite of the fact that the patient was having classical symptoms for retinal detachment.
Proximate Cause
- It was within a reasonable degree of medical certainly that If the patient had been instructed as to the signs and symptoms of retinal detachment and the patient would have been seen by the surgeon on an emergent basis when the symptoms Initially occurred, then the visual outcome would have been much better, and the patient would not be legally blind in the operative eye.
Conclusion
While most cataract surgeries are performed without complications, tens of thousands of patients each year suffer from mild, moderate, or severe complications. Many of these complications could have been avoided with proper medical and surgical care.
About the Author
Duane M. Bryant, MD is a seasoned ophthalmologist with over 30 years of clinical experience with Cataracts, Glaucoma, Diabetic Retinopathy, Branch Vein Occlusion, Central Retinal Vein Occlusion. He has had surgical experience with Cataracts, Glaucoma, Laser Surgery For Glaucoma, Laser Surgery for Diabetic Retinopathy, Laser Surgery for Central Vein Occlusion and Branch Retinal Vein Occlusion, Intravitreal Avastin Injections. Dr. Bryant has been reviewing ophthalmology and cataract injury cases for the past 10 years and has been involved in expert witness, peer chart review and IME work for over 10 years. He can be reached at 410-365-3620 and duanebryant@witheyestosee.com
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