Every surgery has some negative outcomes . The thing is, one should always try to balance the risks against the projected benefits.
There are risks and complications with Cataract Surgery. They include but are not limited to the following.
Specific risks to eye and vision
A cloudy cornea which may or may not settle. This may require further surgery.
Corneal edema/corneal decompensation: The US Food and Drug Administration (FDA) premarket approval studies for intraocular lenses performed from 1978-1982 found an incidence of postoperative corneal edema of 0.06% for posterior chamber lenses, 1.2% for anterior chamber lenses, and 1.5% for iris fixated lenses.
George Corrent, MD PhD Ophthalmology & Neurophysiology, Washington Univ/BPEI (1989)
An acute inflammatory reaction causing pain. This may need further treatment.
A fragment of the cataract may fall into the back of the eye. This may require further surgery.
Vitreous loss: If the posterior capsule is ruptured during surgery, there is a high chance that the posterior vitreous will prolapse, necessitating additional surgery (vitrectomy). This usually necessitates and change in the planned lens implant, and increases the risks of endophthalmitis, CME, inflammation, and retinal detachment.
George Corrent, MD PhD Ophthalmology & Neurophysiology, Washington Univ/BPEI (1989)
Infection of the eye which could cause loss of vision or loss of the eye.
Endophthalmitis: Usually bacterial infection of the interior of the eye. Sterile endophthalmitis does occur, but is rarely as devastating. The risk runs from about 0.1% to 0.03% depending on the study, the population being studied, the surgeons, and the use of antibiotic prophylaxis. Corrected visual acuity of 20/200 or less is a result in about 30–40% of cases. About 50% of cases will recover to 20/40 or better
George Corrent, MD PhD Ophthalmology & Neurophysiology, Washington Univ/BPEI (1989)
Glaucoma (eye disease). This may need further treatment.
Macular oedema (collection of fluid); and retinal haemorrhage (bleed). This usually settles with time.
CME (cystoid macular edema): older studies show a high incidence (30–40%)[2]of angiographic CME. Many of these patients do not notice that their vision is affected by the swelling, and the fluid goes away without additional treatment. Other forms of CME following cataract surgery (associated with diabetes and diabetic macualr edema, or with inflammation/uveitis-iritis) can have more deleterious and long lasting effects on vision.
George Corrent, MD PhD Ophthalmology & Neurophysiology, Washington Univ/BPEI (1989)
Retinal detachment may occur. This will require further treatment.
Any of these complications may occur but these complications are now rare.
Moreover, Any of these complications may permanently damage sight.
Also, Any of these complications may involve a second operation being necessary.
General risks associated with Cataract Surgery.
Infection can occur, requiring antibiotics and further treatment.
Bleeding could occur and may require a return to the operating room.
It is more common if you have been taking blood thinning drugs such as Warfarin, Asprin, Clopidogrel (Plavix or Iscover) or Dipyridamole (Persantin or Asasantin).
Small areas of the lung can collapse, increasing the risk of chest infection. This may need antibiotics and physiotherapy.
Increased risk in obese people of wound infection, chest infection, heart and lung complications, and thrombosis.
Heart attack or stroke could occur due to the strain on the heart.
Blood clot in the leg (DVT) causing pain and swelling. In rare cases part of the clot may break off and go to the lungs.
Death as a result of this procedure is possible.