Abbiamo linee guida rigorose in materia di sourcing e colleghiamo solo a siti di media affidabili, istituti di ricerca accademici e, ove possibile, studi rivisti dal punto di vista medico. Nota che i numeri tra parentesi , , ecc. Sono link cliccabili per questi studi. La maggior parte della malattia si manifesta nel primo anno di vita di un bambino.
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Main article: Glaucoma medication Intraocular pressure can be lowered with medication, usually eye drops. Several classes of medications are used to treat glaucoma, with several medications in each class.
Each of these medicines may have local and systemic side effects. Adherence to medication protocol can be confusing and expensive; if side effects occur, the patient must be willing either to tolerate them or to communicate with the treating physician to improve the drug regimen. Initially, glaucoma drops may reasonably be started in either one or in both eyes. A study of patients in an HMO found half failed to fill their prescriptions the first time, and one-fourth failed to refill their prescriptions a second time.
The possible neuroprotective effects of various topical and systemic medications are also being investigated. Bimatoprost also increases trabecular outflow. Topical beta-adrenergic receptor antagonists , such as timolol , levobunolol , and betaxolol , decrease aqueous humor production by the epithelium of the ciliary body. Alpha2-adrenergic agonists , such as brimonidine and apraclonidine , work by a dual mechanism, decreasing aqueous humor production and increasing uveoscleral outflow.
Less-selective alpha agonists , such as epinephrine , decrease aqueous humor production through vasoconstriction of ciliary body blood vessels, useful only in open-angle glaucoma. Miotic agents parasympathomimetics , such as pilocarpine , work by contraction of the ciliary muscle , opening the trabecular meshwork and allowing increased outflow of the aqueous humour.
Echothiophate , an acetylcholinesterase inhibitor, is used in chronic glaucoma. Carbonic anhydrase inhibitors , such as dorzolamide , brinzolamide , and acetazolamide , lower secretion of aqueous humor by inhibiting carbonic anhydrase in the ciliary body. Laser[ edit ] Argon laser trabeculoplasty ALT may be used to treat open-angle glaucoma, but this is a temporary solution, not a cure. Usually, half of the angle is treated at a time. Traditional laser trabeculoplasty uses a thermal argon laser in an argon laser trabeculoplasty procedure.
Nd:YAG laser peripheral iridotomy LPI may be used in patients susceptible to or affected by angle closure glaucoma or pigment dispersion syndrome. During laser iridotomy, laser energy is used to make a small, full-thickness opening in the iris to equalize the pressure between the front and back of the iris, thus correcting any abnormal bulging of the iris. In people with narrow angles, this can uncover the trabecular meshwork. In some cases of intermittent or short-term angle closure, this may lower the eye pressure.
Laser iridotomy reduces the risk of developing an attack of acute angle closure. In most cases, it also reduces the risk of developing chronic angle closure or of adhesions of the iris to the trabecular meshwork. Diode laser cycloablation lowers IOP by reducing aqueous secretion by destroying secretory ciliary epithelium. Main article: Glaucoma surgery Both laser and conventional surgeries are performed to treat glaucoma.
Surgery is the primary therapy for those with congenital glaucoma. Canaloplasty[ edit ] Canaloplasty is a nonpenetrating procedure using micro catheter technology.
A microcatheter will circumnavigate the canal around the iris, enlarging the main drainage channel and its smaller collector channels through the injection of a sterile, gel-like material called viscoelastic.
The catheter is then removed and a suture is placed within the canal and tightened. By opening the canal, the pressure inside the eye may be relieved, although the reason is unclear, since the canal of Schlemm does not have any significant fluid resistance in glaucoma or healthy eyes.
Long-term results are not available. Here, a partial thickness flap is made in the scleral wall of the eye, and a window opening is made under the flap to remove a portion of the trabecular meshwork.
The scleral flap is then sutured loosely back in place to allow fluid to flow out of the eye through this opening, resulting in lowered intraocular pressure and the formation of a bleb or fluid bubble on the surface of the eye. Scarring can occur around or over the flap opening, causing it to become less effective or lose effectiveness altogether. Traditionally, chemotherapeutic adjuvants, such as mitomycin C MMC or 5-fluorouracil 5-FU , are applied with soaked sponges on the wound bed to prevent filtering blebs from scarring by inhibiting fibroblast proliferation.
Contemporary alternatives to prevent the scarring of the meshwork opening include the sole or combinative implementation of nonchemotherapeutic adjuvants such as the ologen collagen matrix, which has been clinically shown to increase the success rates of surgical treatment.
Glaucoma drainage implants[ edit ] Main article: Glaucoma valve The first glaucoma drainage implant was developed in These are indicated for glaucoma patients not responding to maximal medical therapy, with previous failed guarded filtering surgery trabeculectomy.
The flow tube is inserted into the anterior chamber of the eye, and the plate is implanted underneath the conjunctiva to allow a flow of aqueous fluid out of the eye into a chamber called a bleb. The first-generation Molteno and other nonvalved implants sometimes require the ligation of the tube until the bleb formed is mildly fibrosed and water-tight.
Valved implants, such as the Ahmed glaucoma valve, attempt to control postoperative hypotony by using a mechanical valve. This may require preventive measures using antifibrotic medications, such as 5-fluorouracil or mitomycin-C during the procedure , or other nonantifibrotic medication methods, such as collagen matrix implant,   or biodegradable spacer, or later on create a necessity for revision surgery with the sole or combinative use of donor patch grafts or collagen matrix implant.
NPDS is demonstrated to have significantly fewer side effects than trabeculectomy. The laser-based system is self-terminating once the required scleral thickness and adequate drainage of the intraocular fluid have been achieved. This self-regulation effect is achieved as the CO2 laser essentially stops ablating as soon as it comes in contact with the intraocular percolated liquid, which occurs as soon as the laser reaches the optimal residual intact layer thickness.
Prognosis[ edit ] In open-angle glaucoma, the typical progression from normal vision to complete blindness takes about 25 years to 70 years without treatment, depending on the method of estimation used.
Glaucoma: Que es glaucoma y los tipos más común