Cataract Surgery

Cataract Surgery – Treatment Options And Laser-Assisted Surgery

Let’s understand the eye structure better to understand cataract better. Within the eye the coloured part is called iris and the transparent structure behind it is called the lens. When the normal lens becomes opaque or non-transparent, it is called a cataract. Patients with cataract cannot properly see through their eye lens and hence experience vision difficulties. Cataract develops in different people at different ages, but as a general rule, they develop slowly over a period of time. A cataract can take months or even years to reach a point where it starts affecting the vision in an adverse manner.

Causes Of Cataract

Age-Related Cataract – The natural aging process causes the lens fibres to become opaque over a period of time leading to cataract.

Traumatic Cataract – The traumatic causes include penetrating injury, concussion, electric shock, lightning, Ionizing radiation during ocular tumour treatment, or surgical trauma

Metabolic Cataract – Defects in body metabolism due to diabetes, Galactosaemia or inborn metabolic error, or calcium disorder.

Steroid-Induced Cataract – Excessive intake of oral steroids or instilling steroid drops in the eye.

Drug Induced Cataract – Lens can become opaque due to drugs such as Chlorpromazine, Miotics, Busulphan, Amiodarone, or Gold

Secondary Cataract – Primary eye disease such as glaucoma or chronic ocular inflammation can increase the risk of secondary cataract.

History of Cataract Treatment

The earliest surgical treatment is attributed to Maharshi Sushruta of India. The method was known as ‘couching’, wherein the lens infected with cataract was dislocated backward into the bottom of the eye and forced out of the visual axis. This procedure was performed for more than two thousand years until the mid-eighteenth century.
Subsequent progress in medical technology cataract surgery has made couching obsolete. Currently, The surgeons use advanced techniques,micro-surgical instruments, ultrasonic, and laser-assisted treatments such as Phacoemulsification and Refractive Laser-Assisted Cataract Surgery (ReLACS).
Cataract treatment includes the following steps –

Early cataract detection is treated with prescription glasses.

Cataract surgery is suggested when lifestyle is affected and glasses are not helpful anymore.

Conventional and Advanced surgeries are performed on patients.

The vision improves and the patient is satisfied.

These safe and effective surgeries have 95% success rate.

Cataract Diagnosis

Visual acuity: Vision in both eyes is checked using manual and tools such as glasses and pin-hole view. The macular function is evaluated and the visual post-recovery pattern is assessed.

Intra ocular pressure:If cataract causes intra-ocular pressure then surgery is required to avoid complications such as glaucoma.

Slit-lamp examination: Helps in diagnosis of type, opacity, morphology, etiology, and any other eye disease associated with cataract.

Direct and indirect ophthalmoscopy: Retinal evaluation is conducted using this test. Dense cataracts obstruct retinal evaluation which requires further testing such as B-scan.

A-scan biometry: For mature cataract, the posterior segment of the eye is evaluated to calculate the AL and IOL power for implantation.

Optical biometry: A highly accurate, friendly, and non-invasive method to calculate the IOL power for implants.

Available Treatment Options For Cataract

Extra Capsular Cataract Extraction (Ecce): It is the Conventional technique which requires multiple stitches. The surgeon makes an incision of 10 – 12 mm to remove the clouded lens and then implants a non-foldable lens.

Phacoemulsification – A Micro Incision Cataract Surgery:An advanced and stitch less micro-incisional operation is performed under anaesthesia. The surgeon emulsifies the cataract using ultrasound energy. A phacoemulsifier probe sucks out the liquefied cataract after that. The surgeon carefully implants a foldable and permanent intra- ocular lens in the eye. Vision is restored in a very short time and post-operative rehabilitation and recuperation are minimal.
Need For IOL Implant – The surgeon removes the cataract or the natural lens of the eye. The eye loses its focussing power and becomes similar to a camera without lens. The picture becomes blurred and so an artificial intra-ocular lens or IOL is implanted as a replacement to restore the focussing power.

Refractive Laser-Assisted Cataract Surgery (ReLACS): Our cataract patients can now receive the most advanced and highly reliable Femto Cataract or Laser-assisted cataract surgery.
The “cool” Femtosecond Laser applies laser energy for one trillionth of a second and there is no heat generation. The laser makes precise corneal incisions which and it can also be used in the treatment of astigmatism. The laser is guided by a computerised imaging system known as OCT or optical coherence tomography. The following steps are automated and hence more accurate than the experienced hands of a surgeon –
• Generation of sophisticated 3-D image of the eye • The corneal incision • The anterior capsulotomy • Lens and cataract fragmentation

Types Intraocular Lens

An intraocular lens (IOL) implant is a synthetic and artificial lens that is placed inside the eye as a replacement for natural lens. The different types of IOL are –

Monofocal intraocular lens – : It gives clear point focus either at a distance or close up, but can be used to choose only one focal point.

Multifocal IOLs – :They are popular corrective lens for both far & near vision problems.

Trifocal IOLs : They provide vision correction not only for near and far, but also for intermediate distances. Highly suitable for people who use computers through the day.

Apodized Diffractive Multifocal IOL - : IOL implant with gradual diffractive steps which create a smooth transition between focal points. This IOL bends incoming light to the multiple focal points and increases vision in different light situations.

Accommodative IOL - : Crystalens and Trulign Toric IOLs use a method called accommodation to shift the IOLs position relative to movement of eye muscles for improved eyesight.

Toric IOL For Astigmatism – : A mono-focal IOL with inbuilt correction for treating astigmatism.

Protective IOL filters

IOLs with filters can be selected for additional retinal protection from UV exposure and other damaging radiation. The eye doctor selects the protective filters that are appropriate for the patient’s specific needs.

Cataract Lens Replacement

Future corrections to achieve the best vision possible include –

Additional surgery to replace an existing IOL with another type

Surgeon may suggest Implantation of an additional IOL.

Corneal incisions for Limbal relaxation.

Other types of laser refractive surgery for some cases.