Glaucoma: etiology, epidemiology, classification, symptoms, diagnosis, treatment

Gabrielė Kapūstienė1, Ignė Dumbliauskaitė1, Vitalija Stankunavičiūtė1

1Lithuanian University of Health Sciences, Medical Academy, Faculty of Medicine


Glaucoma is progressive optic neuropathy, which damages the optic nerve due to the disappearance of axonal degeneration of the retinal ganglion cells. The prevalence of glaucoma among people aged 40-80 years is 3.5%. Glaucoma is one of the leading causes of blindness because the patient may not have any symptoms until the late stage of glaucoma. Glaucoma is classified according to the effect of the anterior chamber angle: open angle and angle closure glaucoma. During open-angle glaucoma, optic nerve atrophy develops due to increased intraocular pressure. Angle closure glaucoma develops when the balance between fluid production and removal is disturbed. When the angle of the anterior chamber of the eye narrows or closes completely, fluid leakage is impaired. Chronic open angle glaucoma may have no symptoms for a long time. Patients may complain of impaired vision, eye fatigue. Acute angle closure glaucoma is characterized by severe pain in one eye, visible light circles, redness of the eye, dilated pupil. The clinic is the main diagnostic method for this type. Chronic open angle glaucoma is diagnosed using tests of intraocular pressure, eye fundus, and perimetry. Intraocular examination usually reveals increased intraocular pressure. However, this is not the only and primary diagnostic criteria. When diagnosing glaucoma, it is necessary to examine the fundus and assess the optic nerve disc. This is best done with the slit lamp biomicroscopy. If excavation of the optic disc, a thinning layer of retinal nerve fibers, and a widening neuroretinal margin are seen during the examination, a diagnosis of glaucoma is made. Paracentric scotoma and generalized visual acuity can be examined in an eye examination, but it‘s not a common phenomenon in the early stages of glaucoma. Treatment depends on the type of glaucoma. For an acute angle closure glaucoma, fast ophthalmological examination and treatment is required. Applied drug combination: timolol, apraclonidine and pilocarpine drops, intravenous acetazolamide. After the condition has subsided, treatment of both eyes with laser peripheral iridiotomy is prescribed. The main drugs prescribed for open angle glaucoma work by two mechanisms. Some reduce eye fluid production (beta blockers, carbonic anhydrase inhibitors, alpha agonists), others improve fluid drainage (prostaglandin analogs, cholinomimetics, alpha agonists). The most effective treatment is a combination of drugs. Another treatment is laser therapy (trabeculoplasty).

Keywords: glaucoma, angle-closure glaucoma, open-angle glaucoma, eye disease, intraocular pressure, tonometry, optic disc, excavation, biomicroscopy, perimetry, paracentric scotoma, timolol, acetazolamide, iridiotomy, trabeculoplasty.