CATARACT SURGERY

Cataract is an opacity in the lens of the eye. The normal lens is transparent and allows light to reach the retina. When it becomes opaque (cataract) light does no reach the retina and the patient is unable to see clearly.

Till date there is no proven cure of cataract. The only available treatment is surgery. And so the method and technique of surgery is of importance. Earlier surgery was done only when the cataract was mature and vision was impaired to the extent that daily activities were hampered. But today no one waits so long. Cataract surgery is done electively. This is possible because of the new techniques and developments in surgery
Past techniques

There was a time when cataract was removed through a 12mm large opening. Now with the latest technology we remove the lens through a small opening of 2.8mm with the help of ultrasonic aspiration technique called phacoemulsification. A foldable intraocular lens is then implanted in the eye.

The success rate is close to 99.5 per cent. The present options in phaco surgery are Standard phaco or the first generation phaco surgery using simpler machines and an incision size of 3.2 mm . This was first conducted in late 1970s. In Cold phaco or the second generation surgery, the incision size reduced to 2.8mm but it was much safer since the amount of heat being delivered to the eye was reduced significantly thus reducing the trauma.

Now there is Microincisional (Mini Keyhole) Cataract Surgery. Introduced by Bausch and Lomb this is a revolutionary technology that enables cataract surgery to be done through the a 1.6 mm to 1.8 mm incision.

A new intraocular lens has been devised which can be inserted through this small incision and gets unfolded inside the eye. This is called a micro intraocular lens (MIL). The advantages of this are quicker surgery (sutureless); faster recovery; minimal post–operative restrictions; better vision quality and astigmatism neutral.

After effects

Most people do not need to wear glasses for distance vision but will need them for reading. This can be avoided if a multi-focal lens is placed in the eye. Then glasses may not be required for most work. A few may require glasses to refine their vision.

About five per cent of people get a thickening of the posterior capsule after the surgery, which is called after cataract. This can be easily dealt with by a laser procedure done as an out patient procedure.

The authors are Chennai-based Ophthalmologists.

Causes

Ageing, UV light, Deficiency in protein and vitamins, Intrauterine Infections leading to congenital cataract, Developmental cataract seen in adolescents, Injury and Systemic factors like diabetes mellitus.

Symptoms

Blurring of images, Double images, Image distortion