The rest of the lens is removed by suction. Surgical Options Intraocular Lens IOL Although all intraocular lenses are used to restore clarity of vision, there are many intraocular lens choices available to patients today. Standard lens implants are monofocal, meaning they are designed to correct the vision at one focal length.
If a patient chooses to have IOLs implanted that correct for distance vision in both eyes, they will most likely need glasses to read. Some patients opt for an IOL that corrects their vision for distance in one eye and an IOL that corrects their vision for near in the other eye. The decision to use these lenses must be made on an individual basis. Presbyopia-correcting intraocular lenses are designed to correct for distance and near vision.
The intended goal of these lenses is to decrease the need for glasses. Toric intraocular lenses are used for those patients with astigmatism. Astigmatism refers to an irregularity in the curvature of the cornea. Toric IOLs are designed to correct distance vision and astigmatism. Femtosecond Laser The Femtosecond laser is another option available for your doctor to use during cataract surgery.
If the eye becomes hypotonic, a nylon suture can be placed to close the original incision; another entry can then be made. Big wound. If the keratome entry is too large for the phaco handpiece, excessive fluid outflow can lead to shallowing of the anterior chamber. This situation can be managed by placing an interrupted suture across the main incision.
Poorly shaped incision. If the shape of the incision is not accurate, it may result in unequal distribution of tension and induced astigmatism. Detached Descemet membrane. Improper insertion of the instrument used for incision creation may tear the Descemet membrane at the anterior chamber entry site.
This commonly occurs when the instruments are blunt or if penetration into the anterior chamber is too tangential, as the tip of the instrument may drag the Descemet membrane with it.
To avoid this, the leading tip should be directed posteriorly whenever an instrument is inserted. It is important to recognize an early tear in the Descemet membrane to avoid its extension.
At the end of the procedure, the membranes can be reattached using an injection of ophthalmic viscosurgical device OVD or an air buble into the anterior chamber. Larger tears may require more extensive suturing.
Conjunctival infiltration by balanced saline solution. A limbal incision placed too posteriorly may allow balanced saline solution to fill the conjunctival sac adjacent to the wound.
This can produce a pool of fluid over the cornea and distort the view of anterior chamber structures. A small peritomy allows the balanced saline solution to escape. Premature or too posterior entry of the incision may invite iris prolapse, which can damage the stroma or iris sphincter and result in postoperative pupil irregularities, transillumination defects, peripheral anterior synechia, or uveal incarceration into the incision.
Intraoperatively, pupil constriction and iris bleeding may further complicate the operation. Tamsulosin use increases the incidence and severity of iris prolapse, 5 as does an acute rise in intraocular pressure IOP. However, constructing the incision well, minimizing iris trauma, and reducing positive pressure will decrease the likelihood of iris prolapse. Additionally, care should be taken to avoid excessive injection of fluid and OVD behind the iris.
The solution: Identify and treat the underlying cause. If iris prolapse occurs despite your precautions, proper management starts with identifiying the underlying cause:. In this case, all instruments should promptly be removed from the eye. An OVD or balanced saline solution can be injected through the sideport incision to tamponade the bleeding. If the incision does not self-seal, pressure can be applied over the wound with a gloved finger.
It is advisable to use intravenous mannitol to shrink the vitreous volume. In the case of nonprogressive focal choroidal hemorrhage, the surgeon can drain it via a sclerotomy created 3. If IOP is still high and the anterior chamber is shallow after 15 minutes, surgery should be stopped and completed in a later session. Aggressive attempts to reposition the iris without alleviating the underlying cause may result in serious iris damage.
This device is called an intraocular lens , or IOL for short. During any form of cataract removal, special precautions are taken to make sure you're completely relaxed and pain-free. At worst, patients can experience a slight sensation of pressure, but this feeling isn't painful.
A small incision is made along the side of the cornea. A high-frequency ultrasound device or laser is used to carefully break up the cloudy lens into small fragments.
After all fragments have been removed, the surgeon places the IOL behind the pupil and the colored part of the eye iris in the same spot your natural lens occupied. If you need surgery in both eyes, your cataract surgeon will typically wait one to three weeks between procedures, to give the first eye a chance to heal. The most common type of cataract removal surgery is called phacoemulsification , or phaco for short.
A phacoemulsification procedure uses high-frequency ultrasound waves to break up the cloudy lens. The phaco operation is now performed with smaller incisions than ever before, so healing is faster with a much lower risk of complications.
Monofocal lenses — The standard options for most surgeries. These may still require the use of eyeglasses or reading glasses after surgery. If prescription glasses are needed, your eye doctor will prescribe them about a month after surgery. Optionally, presbyopia can be treated by adjusting the power of one of your monofocal IOLs to create a condition called monovision. Accommodating lenses and multifocal lenses — Available for patients with presbyopia.
These lenses can correct your reading vision without sacrificing your distance vision. Both of these IOLs provide a greater range of vision after cataract surgery than conventional monofocal lenses.
Extracapsular surgery — Instead of breaking up the cloudy lens with ultrasound, a surgeon will remove the core in one piece, then the rest with suction. Extracapsular surgery involves a longer incision and antibiotic eye drops before the operation. This type of cataract surgery procedure is typically only performed in complicated cases.
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