Cataract surgery viscoelastic is also referred to as ophthalmic viscosurgical device (OVD) is used as an article writing material to find out thick substances to make phacoemulsification easier and safer.
Cataract Surgery Viscoelastic
We need to know together that cataracts are a natural process. In the Indonesian dictionary, cataracts is a disease in the eye that cause the lens of the eye becomes turbid. With the opacification of the lens inside the eye, cataracts can cause decreased vision. The eyepiece is responsible for clearly focusing the object, if the lens is turbid, then the vision that was obvious becomes blurred and difficult. You can have cataracts in one eye or both. Cataracts can occur at any age, but in general cataracts are considered part of the aging process. The incidence of cataracts is even higher in those aged over 75 years. However, the good news is that cataract treatments are very successful with the latest surgical techniques.
Viscoelastic, also referred to as ophthalmic viscosurgical device (OVD) is a viscous substance that allows us to make phacoemulsification easier and safer. Viscoelastic substances are often used in cataract surgery to protect the corneal endothelium and to facilitate the insertion of intraocular lenses (IOL). After the first incision is made, the eye has a tendency to collapse due to water leaks out. The larger the incision, the greater the tendency of the eye to collapse and the greater the risk for the patient. Replacing a thicker aqueous with viscoelastic can prevent eye collapse.
The main purpose of using viscoelastic substances in cataract surgery is the prevention of corneal endothelial loss. At the beginning of surgery, viscoelastic is placed into the eye by performing an exchange through an injection of OVD while the aqueous is forced out of the eye. This is done by placing the cannula in the anterior chamber and injecting the distal, thus allowing the liquid to come out of the same incision. This goal is met by deepening the anterior chamber, mechanical endothelium protection against surgical trauma, ultrasound energy absorption, and intraocular lens coating. The first and most viscoelastic use in eye surgery is a sodium hyaluronate (NaHA) solution with a molecular weight of four million daltons, and a viscosity of 229,000 cP (Healon). This substance is a good endothelial protective function in cataract surgery, especially phacoemulsification, documented in the literature.
There are two main classes of Cataract Surgery Viscoelastic
There are two main classes of viscoelastic, e.g. dispersive and cohesive, and they behave differently. Dispersive OVD has a consistency of syrup or molasses, and they can flow like a viscous liquid. This gives OVD a dispersive ability to coat the ocular structure well, and this layer is not easily washed away by the flow of balanced saline solution during operation. This dispersive OVD coating is helpful for protecting the corneal endothelium from ultrasonic waves during surgery. Cohesive OVD is denser than liquid, and they have a consistency of gelatin, which means that they cannot coat or flow well. However, because it is thicker, they are able to maintain space and press the eye well. A cohesive OVD is useful for keeping the anterior chamber formed, to keep the anterior capsule flat during the manufacture of capsulorrhexis, and to move or manipulate iris or other tissues and to keep empty capsule bags open for IOL insertion.
At the end of the operation, it is important to remove the viscoelastic from the eyes thoroughly. If viscoelastic is not removed it can block trabecular meshwork, and patients will experience high IOP. Viscoelastic dispersives can be more difficult to remove because they have a tendency to spread and coat ocular structures. The cohesive viscoelastic tends to stick together as one mass and is usually easier to remove completely. In addition, the use of viscoelastic can make phacoemulsification easier for the surgeon and also safer for the patient. The moderate OVD may have some dispersive properties as well as some cohesive properties. For many surgeons, using OVD is the best of both and they can use it as exclusive viscoelastic for the entire operation. Other surgeons may prefer to have two viscoelastics, one cohesive and one dispersive, for each operation. With the existing reason being an integral part of our operations.
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