A cirurgia de catarata apresenta uma elevada taxa de sucesso e é, de acordo com o British Journal of Ophthalmology, o procedimento mais comum no mundo inteiro.

O procedimento cirúrgico habitual é a facoemulsificação do cristalino com implante de lente intraocular, que pode ser assistida com laser femtosegundo, que hoje em dia utilizamos preferencialmente.

The first step in this case is a continuous circular opening in the anterior capsule of the lens (capsulorhexis). The nucleus is then divided into small fractions and the incisions necessary for emulsification and aspiration of the nuclear remains (removal of the cataract) are made through the incision made previously. The entire first phase, crucial for a good refractive result, is performed by laser. After eliminating the cataract, an intraocular lens is implanted, which is chosen in a personalized manner.

Although the purpose of intraocular lens implantation is to replace the lens and eliminate existing opacification, it can also correct previously existing refractive errors.

Cataract surgery should be recommended by the ophthalmologist and appropriate according to the clinical situation in question. However, we should consider cataract surgery whenever our day-to-day activities, and consequently our quality of life, are compromised. These two factors vary from case to case, and depend on the visual demands and needs, on a personal and professional level.

Femtosecond Laser

As mentioned above, cataract surgery can be performed with the aid of the femtosecond laser.

This laser, as is the case with the one used in the CPO clinic, is a high precision surgical laser, which is used for cataract surgeryLASIK ( flap preparation) and correction of astigmatism (arched incisions).

The capsulotomy or capsulorhexis, as mentioned above, is a circular incision in the anterior capsule of the lens. This opening must be continuous, regular and centred on the visual axis. This is very important for good centring of the intraocular lens, especially if it is a multifocal lens or an extended focus lens (EDOF). If the lens is not perfectly centred, this can lead to undesirable refractive changes. This is why we prefer the use of the phased-array laser in our cases.

The fragmentation of the lens nucleus facilitates the phacoemulsification The fragmentation of the lens makes it easier for the surgeon to remove the remains of the cataract. Both contribute to a clear cornea, without oedema after the surgery and with immediate recovery

It is possible in the same surgery to perform a correction of astigmatism of values up to 1.5 dioptres, dispensing with the use of toric lenses. The laser precisely makes incisions (arches) in the axis to be treated, allowing for the correction of low value astigmatism , thus improving the refractive result of the cataract surgery.

How to choose the right intraocular lens?

The choice of intraocular lens has to be chosen and individualised for each patient according to their desires and needs for recreational or professional vision. The main goal should be to achieve the best possible visual acuity that gives the patient the maximum quality of life.

The doctor always takes into consideration ametropia (existing refractive defects such as myopia, hyperopia and astigmatism), the anatomical and structural conditions of the eye to be operated on, the existence of any underlying pathology and whether it has undergone any previous ophthalmological surgery. It is also necessary to carry out complementary diagnostic tests in order to choose the intraocular lens to be implanted.

Previously there was the possibility of performing cataract surgery, replacing the lens with a monofocal intraocular lens, aiming at emmetropia (the ability to see well at any distance without correction). Nowadays, due to constant scientific and technological advances, patients have the chance to opt for a customised intraocular lens, which allows, besides the correction of the refractive error, good intermediate and reading vision enabling independence from the use of glasses.

Clique na imagem em baixo para ver um vídeo de um dos nossos especialistas a explicar os diferentes tipos de lentes intraoculares.

Cataract surgery is the most frequent surgery in the ophthalmology specialty, and is, according to the WHO, the main cause of reversible blindness worldwide, and the second main cause of low vision.

It is generally a relatively quick operation, but it may vary according to the type of cataract.

Cataract surgery is expected to take 15 to 20 minutes and the patient will stay in the clinic for about 2 hours, from arrival, preparation and until departure.

After arrival at the clinic for surgery the eye to be operated on is dilated (the pupil) with appropriate eye drops. This allows access to the opacified lens and the previously described steps of the surgery. In our clinic the patient lies down on the operating table where all the surgical steps are performed, including the use of the laser, which is more practical for both the patient and the surgeon.

As far as recovery from cataract surgery is concerned, in most cases it is quick and without major complications or restrictions in daily life.

It is important that the patient complies with all medical instructions and does not miss any post-operative follow-up appointments

If there are complaints during recovery, a medical re-evaluation is recommended.

Cataract surgery is proposed by the ophthalmologist. It is important that the doctor informs you of the entire process and the associated risks.

Although the risks of cataract surgery are reduced, they are not zero. As in any other type of surgery, there are always associated risks.

All complications are manageable, but involve a delay in recovery and the possibility of further surgery.

A possible complication is the rupture of the posterior capsule (the membrane on which the intraocular lens is placed and which supports it) during the surgery, during the aspiration phase, which sometimes involves the loss of remains of the lens into the vitreous. If the rupture occurs during the implantation of the lens, it may move into the vitreous.

In either case, it will be necessary to perform a vitrectomy to remove the remains of the lens or the intraocular lens, as the case may be, and implant a scleral support lens (the lens is attached to the wall of the eye) or a sulcus (the space between the posterior face of the iris and the periphery of the posterior capsule) to restore the patient's vision.

Cataract surgery increases the risk of retinal detachment by 1% in the years after surgery. retinal detachmentin the years after surgery.

Cystoid oedema of the macula (the central part of the retina where the image is formed) is another possible complication, less frequent nowadays, due to new surgical techniques. If it occurs, visual acuity is low for weeks or months until there is a recovery, most of the time complete.

The possibility of a catastrophe occurring is residual because endophthalmitis (serious intraocular infection or an expulsive haemorrhage (serious internal bleeding) are episodes that the vast majority of surgeons do not see during their active life today.

Finally, opacification of the posterior lens capsule is the most frequent complication following cataract removal and is easily resolved. It occurs in around one third of operated patients, caused by excessive scarring with retraction of the capsule or by the growth of remnant lens cells, with symptoms similar to those of cataract. The patient complains of blurred vision, especially in bright light, and difficulty in reading. The opening of the capsule by YAG laserThe opening of the capsule is simple and performed in the doctor's office on an apparatus similar to the usual observation apparatus without any previous preparation.

Prof. Dr. Tiago Ferreira

Dr Pedro Arede

Dr Samuel Alves

Dr. Pedro Neves

Dr. Bernardo Feijóo

Dr. Joana Valadares

Dr Manuel Marques

Dr. Miguel Lacerda Leitão