What is myopia? Myopia is a refractive error in the eye, where rays of light are not concentrated in the retina, as it is normal, but at some point in front of it. The main symptom is blurred perception of distant objects. The myopic person in order to see clearly distant objects, often exploits the stenopaic slit mechanism, blinking and slightly closing the ciliary cleft. The myopic eye sees near objects clearly, exerting less or no adjustment (depending on the degree of myopia). Myopia usually develops in the early years of a person's life, and becomes noticeable in the early school years, where the child’s needs extend to distant vision. This myopic state usually follows a benign course and after a gradual increase is stabilized by adulthood.
Diagnosis Myopia is most often diagnosed through an eye examination carried out by an eye specialist.
Treatment Myopia can be corrected with the following methods:
- Eyeglasses with corrective lenses (negative lenses)
- Contact lenses
- Laser refractive surgery
What is astigmatism? In astigmatism, the refractive power of the eye is not the same in all meridians, thus it is not possible to capture the rays of light entering the eye at a single point. In most cases, the astigmatism is caused by disorders of the shape of the cornea. In astigmatism both distant, and near objects appear distorted. This is due to the curvature of the cornea, as it is not uniform over its entire surface, resulting in an inability to focus rays of light on the same plane.
- with a simple measurement of the person’s visual acuity
- with a cornea topography (pentacam, topolyzer)
- Eyeglasses with cylindrical lenses
- Toric contact lenses
- Laser refractive surgery
What is hyperopia? Hyperopia is a refractive defect of the eye, where a parallel beam entering the eye is not focused on the retina, but it encounters the retina before creating a focus point. Therefore, each point of an object is depicted on the retina as a circle of confusion, and the object appears blurry. The hyperopic eye cannot see clearly both distant, and near objects.
Diagnosis Hyperopia is diagnosed through an eye examination carried out by an eye specialist.
- Eyeglasses with positive spherical lenses
- Contact lenses, soft or semi-soft
- Laser refractive surgery
What is presbyopia? Presbyopia is a visual defect that occurs in all people over the age of 40-45 years. Substantially, this is not an actual disease, but a normal aging process of the eye’s crystalline lens. The main symptom is limited vision for near distances and objects. The person finds it difficult to read and gets tired after a short time of work. At the beginning of the symptoms, the person with presbyopia is relieved from discomfort by moving the subject he wants to see, or the document he wishes to read, further away. Over the years, however, the progressive decrease in the ability to adapt makes reading more difficult, and ultimately impossible.
Diagnosis Presbyopia is diagnosed through an eye examination carried out by an eye specialist.
- Magnifying glasses
- Bifocal or multifocal glasses
- Contact lenses
- Reading eyeglasses
- Surgical treatment PresbyLASIK
One of the most common eye diseases is Cataract. The most common form is the one called "senile cataract", which occurs due to normal aging of the body, and mainly affects the elderly. But it can also be caused by diseases, systemic or ophthalmic, by taking drugs or injury (traumatic cataract), while on some rare occasions it is presented at birth (congenital cataracts).
What is cataract? A cataract is the clouding of the crystalline lens of the eye. The lens, which lies behind the iris (the colored part of the eye) is normally clear. Light passes through it to reach the retina, the back surface of the eye. With age, this lens loses its original texture and begins to blur. This results in light not entering the bulb in its full intensity, and gradually decreased vision. Depending on the degree of turbidity, the rate of progression, and the point of the lens which displays this blurriness, depends the cataract’s progress speed.
The ONLY symptom caused by the cataract is gradual vision loss. Pain, a sense of a foreign object, redness, lacrimation ARE NOT cataract-related symptoms.
Cataract removal technique
- The most widely used technique is phacoemulsification. During surgery, the blurry lens is removed and replaced with a clear, artificial intraocular lens (IOL).
- Femtosecond Laser - LenSx
Latest cataract surgical equipment for the cataract removal surgery.
What is glaucoma? Glaucoma is a disease of the eye, which due to the blocking of the flow of aqueous humor produced by the ciliary body, the intraocular pressure increases and destroys the ganglion cells of the retina. If the intraocular pressure remains high without being treated, then there is a risk of damaged vision. The ganglion cells help the optic nerve to transfer information. General symptoms of glaucoma are photosensitivity, lacrimation, clouding of the cornea, pain, dilated eye, and eyelid spasms. Children must be submitted directly to surgery if affected by glaucoma.
Glaucoma is actually a group of diseases that cause optic nerve damage. The damage occurs as a result of the increased pressure caused by the fluid within the eye. This increased pressure is caused by an excess of fluid inside the eye. The result is the gradual loss of vision. It is possible to save the patient's vision in case of glaucoma, if diagnosed and treated early. This disease unfortunately begins with no apparent symptoms. So the person with glaucoma usually does not know of his situation, until it has already caused severe vision loss. Approximately 50% of those who have glaucoma do not know about it. The damage caused by glaucoma is irreversible.
- Anti-glaucoma eye drops
- Selective Laser Trabeculoplasty
- Surgical treatment - Trabulectomy
What is keratoconus? Keratoconus is a degenerative, non-inflammatory disease of the cornea. This is a progressive disorder where a thinning of the cornea occurs centrally or paracentrally, taking a conical shape. Keratoconus usually appears in adolescence, and its evolution is progressive until the third to fourth decade in a person’s life, after which it follows a slow progression. In 85% of cases both eyes are affected, but the progression of the infection can be highly asymmetric. Incident frequency of keratoconus in the general population ranges between 50 to 230 per 100,000. Keratoconus is considered a multifactorial disease with unclear causality.
- Decrease in visual acuity
- Sudden astigmatism increase
- Distorted vision at all distances
- Insufficient night vision
- Monocular diplopia
Diagnosis: Keratoconus is diagnosed through corneal topography (Pentacam – Placido).
I. AGE-RELATED MACULAR DEGENERATION
Age-related macular degeneration (AMD) is the leading cause of irreversible severe vision loss. The occurrence of this degeneration increases with age.
- Atrophic (non-exudative - dry type), which develops slowly and accounts for 90% of cases of patients with AMD.
- Exudative (wet), which is destructive and in some cases the central vision may be lost within a few days.
- Metamorphopsia (deformation)
- Blurry vision
- Scotomas (small areas where loss of vision occurs)
- Testing of visual acuity
- Amsler table testing
- Slit lampt examination
- Mydriatic fundus examination
- Fluorescein angiography
- Anti-VGF injections
- Laser photocoagulation at paramacular membranes
- Surgical dislocation of extensive submacular hemorrhage
II. RETINAL DETACHMENT
Retinal detachment is the eye condition where the retina becomes detached from the underlying layers of the eye. The retina does not work when it is detached and vision is blurred. Retinal detachment is a serious problem and causes almost immediate blindness, if not treated at the early stages.
Almost all patients with detachment need to undergo immediate surgery, in order for the retina to return to its normal place. There are several surgical techniques that may be applied. The decision on which technique will be applied, and whether the latter will be under local or general anesthesia, depends on the characteristics of the detachment.
- Rhegmatogenous (most common detachment)
Symptoms: Photopsia, floaters, vision loss in the form of a curtain or wall.
- Slit lamp assessment
- Mydriatic fundoscopy
- Examination of the vitreous posterior
- B-scan ultrasonography in turbid refractive media
- Argon Laser crack retinal photocoagulation (prophylactic treatment)
- Pneumatic retinopexy (using air and cryotherapy)
- Hard graft and cryotherapy
III. VITREOUS DETACHMENT
Vitreous is the part between the crystalline lens of the eye and the retina. With age, the vitreous degenerates, is fluidized, and can be dislodged from the back of the eye. This is called a posterior vitreous detachment. It is a very common and usually harmless condition.
- Sudden vision loss along with flashes and floaters
- A curtain or wall that obstructs vision partly or fully
- Sudden increase in floaters
Diagnosis: Slit lamp examination, and mydriatic fundoscopy in order to determine if there are any retinal cracks.
- There is no appropriate pharmaceutical treatment.
- Scar formation around the tear using Argon-laser [if the examination found suspicious peripheral regions of the retina (degenerations - holes - cracks), then Argon-laser photocoagulation can be applied to prevent any retinal detachment (RD)].
IV. MACULAR HOLE
Macular hole is normally perceived on the one eye of the patient when he accidentally closes the other eye.
Visual acuity is usually reduced up to 1/10.
Treatment: Vitrectomy and gas insufflation.
Post-operative: Patient must remain in a face-down position(3-5 days).
Hole healing is achieved in 80% of the cases with resolution of the central scotoma, and a significant improvement in visual acuity.
- Retinal detachment
- Acceleration of cataract development
V. EPIRETINAL MEMBRANE (ERM)
Idiopathic epiretinal membrane mainly affects otherwise healthy elderly individuals.
The clinical appearance of epiretinal membranes depends on the density, and the existence of any deformation of the retinal vessels.
There are two forms, cellophane maculopathy, a relatively mild case, and the most severe form, macula pucker.
- Patients may be asymptomatic, or show slight metamorphopsia.
- Visual acuity is normal, or slightly reduced.
B. Macula pucker Metamorphopsia and reduced central visual acuity at 5/10, or less, are reported, depending on severity.
Treatment: Surgical removal of the membrane with epimacular vitrectomy. Visual acuity is improved by at least 2/10, in relation to the preoperative measurement, and there is significant reduction in of metamorphopsia symptoms.
VI. DIABETIC RETINOPATHY
Diabetic retinopathy is one of the major causes of blindness. It affects diabetic patients, and is caused by lesions of the retinal vessels.
These vessels in diabetic patients may have small bleedings, small occlusions with consequent ischemia, and in advanced stages they may develop new, abnormal vessels in the retinal surface. The new vessels can cause bleeding inside the eye, while in more advanced cases they can lead to retinal detachment and irreversible vision loss.
The most common type of diabetic retinopathy is retinopathy of the substrate, characterized by micro-aneurysms, small hemorrhages, soft and hard exudates, and small areas with capillary occlusion, maintaining normal visual acuity.
- Gradual loss of vision
- Acute loss of vision
- Slit lamp exam
- Gonioscopy (in case there is suspicion of a neovascular glaucoma)
- Fluorescein angiography
- Focal laser treatment
- Panretinal photocoagulatio
- Anti-VGF injections
- Vitrectomy to treat vitreous hemorrhage, and tractional retinal detachment.
Observation: An annual fundus examination should be performed to all diabetic patients. In case of mild diabetic retinopathy, it is recommended to review every six months, to monitor the progression of the disease, and in severe cases, every 2-3 months.
VII. CENTRAL SEROUS RETINOPATHY
Central serous chorioretinopathy affects the macula, and is seen more frequently in patients aged between 20 and 40 years old, at a ratio of 8:1 between men and women. The etiology is unknown, and usually stress factors are implicated.
The onset is sudden and patients may experience metamorphopsia, blurred vision, and central scotoma. The condition usually follows a self-healing course in a few months, and the recovery can be accelerated by Laser photocoagulation.
VIII. HYPERTENSIVE RETINOPATHY
Systemic hypertension causes disturbances in the choroidal circulations, the retina, and the optic disk, and the severity of these disorders depends on the speed of onset, the duration of the hypertension, and the patient’s age.
IX. VASCULAR RETINAL DISORDERS
A. Retinal artery occlusion B. Retinal vein occlusion
A. Retinal artery occlusion
Symptoms: Acute, severe, painless loss of vision
Causes: A stroke is a common cause of retinal artery occlusion.
Vessel occlusion can occur due to: I. Atherosclerosis II. Periarteritis III. Hematological disorders IV. Migraine
Α.1 Central retinal artery occlusion Central retinal artery occlusion usually occurs due to atherosclerosis, while it may also be the result of calcified emboli. It occurs suddenly, causing significant vision impairment.
Α.2 Branch artery occlusion Branch artery occlusion is usually a cause of emboli . It causes sudden partial visual field loss..
Treatment: An immediate (within hours) treatment is mandatory, which can save a significant amount of the visual function.
B. Retinal vein occlusion
B.1 Branch retinal vein occlusion Symptoms: I. Reduced vision II. Partial visual field loss
B.2 Central retinal vein occlusion Symptoms: I. Reduced vision II.In case of complications, pain and floaters may occur.
- Intravitreal injections with Anti-VEGF agents, or corticosteroids
- Laser photocoagulation in case of macular edema, or neovascular complications.
X. HEREDITARY FUNDUS DYSTROPHIES
Retinitis pigmentosa is the general name of a group of inherited diseases, which are characterized by the progressive decline of the photoreceptor’s functionality, and the pigment epithelium’s.
The age of onset, the rate of progress, the final loss of vision, and the presence or absence of ocular manifestations, often depend on the nature of heredity.
- Reduced night vision (nyctalopia)
- Reduced color perception
- Peripheral vision loss
- Blurred vision
- Reduced vision
- Cystoid macular edema
- Optic disc drusen
Familial macular degeneration (ν. Stargardt)
ν. Stargardt often occurs during the first, or second decade of a person’s life, with reduced visual acuity, and reduced color perception (dyschromatopsia of the red/green type).
Diagnosis: Fluorescein angiography
- Blurred vision
- Reduced vision