A
A- Avitaminosis
Severe form of vitamin deficiency (vitamin A)
Abrasio corneae
Abrasion of the corneal epithelium
Adduction
Movement (of the eyeball) toward the medial axis of the body
Amotio retinae
Detachment of the retina
Aniridia
Congenital absence of all but the root of the iris
Antiviral
Inhibiting the growth of viruses
Atrophy
Degeneration, decline or decrease, as from disuse
Amino acids
The smallest building blocks of proteins
Abduction
Outward movement of the eyeball
Albumin
A protein that also occurs in the tear film
Abducens nerve (nervus abducens)
6th cranial nerve (motor nerve, innervates the lateral rectus muscle)
Amblyopia
Impaired vision in one eye without discernible damage to the eye or optic nerve
Applanation, applanation tonometry
Method of measuring the pressure inside the eye by applying pressure to flatten the cornea
Abrasive particles
(self-explanatory): used in contact lens cleansers
Allergen
Allergic substance
Absorption
A taking in or reception of one material by another
Amaurosis fugax
Temporary, episodic blindness or severe visual impairment
Anisometropia
An imbalance of more than 2.0 dpt in the power of the two eyes to refract light (=indication for contact lenses)
Apex Corneal
The steepest zone of the eye in cases of keratoconus
Adsorption
Physical binding of materials on surfaces
Aphakia
Lack or loss of the lens in an eye
AC/A
Accommodative convergence/accommodation
Allergy
An abnormal immune response upon contact with an allergen; in the eye, for example, skin or mucous membrane hypersensitivity upon contact with pollen, dust, medications, contact lenses and their care products, preservatives, etc.
Anisocoria
Inequality in the size of the pupils
Arcus lipoides, arcus senilis (corneae)
A narrow ring or opacity at the corneal margin, commonly occurring in the elderly
Asthenopia
Eye fatigue resulting from strain on the ciliary muscle, especially due to near work (computer screen, etc.) that manifests in burning, double or blurred vision, watering eyes, tension and headaches
Astigmatism
Subdivided into external or internal astigmatism (corneal distortion or crystalline lens distortion)
Atropine
Medication (mydriatic) that leads to dilated pupils and accommodation paralysis
B
Bacteriostatic
Inhibiting the further growth of bacteria
Barraquer
Term for thin surgical sutures
Bevel
The edge of a contact lens (tangential bevel, ski-tip)
Binocular
Involving both eyes
Bitoric
Contact lens with a torus on both the front and back
Blepharitis
Inflammation of the eyelid margin
Blepharoconjunctivitis
Inflammation of the eyelid and conjunctiva
Boeck's disease (B. disease), sarcoidosis
Proper name; systemic general disease of unknown aetiology, which may be associated with uveitis, iridocyclitis, conjunctivitis, retinitis
Bactericide
Any substance capable of killing bacteria
Biocatalyst
Substance that controls biochemical processes (e.g. enzymes)
Back surface toric
Torus on the posterior surface of the contact lens
Benzalkonium chloride (BZK, BKC, BAK or BAC)
Preservative used in rigid contact lens solutions and many eye drops
Beta blocker
Medication that competitively inhibits the neurotransmitters (noradrenalin, adrenalin) at the cellular beta receptors of an organ
Blebs
Visible black spots in an otherwise honeycombed cell structure of the corneal endothelium
Buffer
Chemical compound; used to stabilize the pH value of a solution (e.g. borate buffer)
C
Cornea
The transparent, anterior part of the external coating of the eye, covering the iris and pupil and continuous with the sclera
Chlorhexidine
Chemical compound, preservative, used in contact lenses and contact lens care products
Chemosis
Oedema of the bulbar conjunctiva
Conjunctiva
Mucous membrane that lines the exposed portion of the eyeball and the inner surface of the eyelids
C. congenita
Congenital cataract
Choroid
The vascular layer of the eye, between the retina and the sclera
CMV
Abbreviation for cytomegalovirus, a herpes virus that induces retinitis
Congenital (cong.)
Of or relating to a condition present at birth
Contusio bulbi
contusion of the bulb
Corpus vitreum
Vitreous body
C. senilis
Old-age related cataract
conjunctiva
Mucous membrane that lines the exposed portion of the eyeball and the inner surface of the eyelids
Contraceptive
Product to prevent conception or impregnation
Cataract
Clouding of the normally clear lens of the eye
C. incipiens
An incipient cataract
CAB
Cellulose acetate butyrate – a plastic used in manufacturing rigid contact lenses
Concomitant
Moving together (both eyes move to the same extent)
Conjunctivitis
Inflammation of the conjunctiva
Curtius syndrome
An isolated hemihypertrophy
Corpus ciliare
Ciliary body
Cryo-
Icy cold or frost/freezing
Cum correctione (cc)
With (optical) correction
Cornea
The transparent, anterior part of the external coating of the eye, covering the iris and pupil and continuous with the sclera
Convergence
Inward motion of both eyes for the purpose of near vision
Conjunctivitis
Inflammation of the conjunctiva
Coloboma
A hole in one of the structures of the eye – generally the iris
Contamination
Impurity, adulteration, contagion, pollution
Coagulation
Clotting or thickening (of a fluid)
Convergent
Converging (tending to meet in a point or line)
Corneal topography
Graphic illustration of the entire surface of the cornea (evaluation of measurement data on the central and peripheral cornea in the form of a topographic map)
C. matura
A mature cataract – end stage
Chelate
Chemical compound that is used for stabilization and antimicrobial purposes in preservatives, e.g. EDTA in contact lens care products
C. juvenilis
Cataract appearing in adolescence
Cylinder (cyl)
This indicates the amount of lens power for astigmatism and represents the difference in the greatest and weakest powers of the eye
Chlorobutanol
Chemical compound, preservative, used in contact lenses and contact lens care products
Coloboma
A hole in one of the structures of the eye – generally the iris
Ciliary body (corpus ciliare)
Ray body (holds the zonules, i.e. the suspension apparatus of the lens, and produces the aqueous humor)
D
Dystrophy
Trophic disorder and associated tissue changes
Descemet’s membrane
A thin layer of the cornea
Dacrostenosis
Obstruction of the nasolacrimal duct
Diabetes mellitus (diabetes)
A carbohydrate metabolism disorder that can affect the eyesight
Dimple veiling
Air bubble dimples (in the eye)
Divergent
Diverging (tending to move apart)
Dysfunction
Malfunctioning
Dacrocystitis
Inflammation of the tear (lacrimal) sac
Dehydration
Loss of fluids
Disinfection
Killing or inactivating pathogens (bacteria, fungi, viruses) through the use of physical or chemical processes or products
Dk/tAV value
Measurement of the oxygen permeability of a contact lens material as a function of its average thickness (tAV)
Dk/t value
Measurement of the oxygen permeability of a contact lens material as a function of its central thickness (transmissibility)
Desorption
Removal of adsorbent materials (in contact lens care, removal of organic deposits on contact lenses, such as through the use of surfactants)
Dk value
Measurement of the oxygen permeability of a contact lens material – the higher the Dk value, the more permeable the material
Desiccation
Dehydration; corneal desiccation can lead to local punctate keratitis in the lower third of the cornea
Dioptre
Unit of measurement for the refractive power of optical lenses; the refractive power (in dioptres) is reciprocal to the focal length of the lens (in metres)
Drusen
Yellowish-white spots at the posterior pole of the eye, visible with an ophthalmoscope; deposits in Bruch’s membrane between the RPE (retinal pigment epithelium) and the choroid can lead to macular degeneration
Duane syndrome
A rare congenital form of strabismus, usually characterized by the inability of an eye to move outwards
E
Etiology
Cause of a disease
Entropium, Entropion
Inwardly rotated eyelid
EDTA
Ethylenediaminetetraacetic acid - see Chelat
ectropium
Eyelid that sticks out
Ectropion, ectropium
Eyelid that sticks out
Eczema
Inflammatory reaction of the skin
Endothelium
The innermost cell layer of the cornea
Enophthalmos
Eyeball that is sunken or has receded within its orbit
Epilation
Eyelash (or any hair) removal
Epithelium
Upper or outer cell layer, such as of the cornea and the conjunctiva
Eccentricity
Measure of deviation from circularity. Used to mathematically determine the degree of flattening on the inner contour of a contact lens or cornea, based on the variable distance from the centre of an ellipse to its perimeter. The cornea is more similar to an ellipsoid than to a spherical surface.
Endotoxin
A toxin from the outer cell layer of gram-negative bacteria, consisting of lipopolysaccharides, released upon the death of the bacteria
Epiphora
An overflow of tears
Episcleritis
Inflammation of the episcleral tissue
Erosio, corneaе
Superficial erosion of the cornea
EW
Extended wear of contact lenses, such as overnight
Excavation
Hollow, indentation (is primarily used in connection with the optic nerve papilla)
Exophthalmos
Protruding eyeball
Enucleation
Surgical removal (of the eyeball)
Enzymes
Organic compounds that are formed in living cells (but can also be synthesized); biocatalysts which control processes in the organism without changing their own structure, used in contact lens care for neutralization of hydrogen peroxide
Epicanthus
A fold of skin extending vertically over the inner angle of the eye, characteristic of Mongolian people
Exsudate
Fluid and cell emission from the blood and lymph vessels, caused by inflammation
F
Facial nerve paralysis
Paralysis of the 7th cranial nerve
Fluorescein
Dye used to colour epithelial defects and to assess the fit of rigid contact lenses
Fluorosilicone-acryllate copolymers
Material that is highly gas permeable, used for rigid contact lenses
Foramen
Literally: window
Foramen retinae
Hole in the retina
Fornix
The junction between the tarsal and the bulbar conjunctiva
Fungistatic
Inhibiting the growth of fungi
Facial nerve (nervus facialis)
7th cranial nerve (supplies the facial musculature, various glands, the gustatory nerves, etc.)
Fluorescein angiography
Technique for making the blood vessels (in the retina and choroid) visible using fluorescent dye (fluorescein, indocyanine green)
Front toric
Torus on the front of the contact lens
Follicle
Vesicular cavity structure or cell conglomerate
H
Haematoma
A localized swelling filled with blood, resulting from a break in a blood vessel
H2O2
Chemical designation for hydrogen peroxide
Highly hydrophilic
Soft contact lens material with a high water content (>60% H2O)
Hydrophobic
Repelling, tending not to combine with, or unable to dissolve in water
Hyperopia, hypermetropia
Farsightedness
Hyphaema
Blood in the anterior chamber of the eye
Hypoxia
Oxygen deficiency
Hyposphagma
Bleeding under the conjunctiva
HEMA
Hydroxyethylmethacrylate – contact lens material with approx. 38% water content
Heterotropy
Manifest strabismus
Hydroxyethyl cellulose
Chemical compound used in contact lens care products and eye drops as an additive to increase viscosity
Herpes (corneae)
Herpes infection of the cornea
Hydration
The binding of water to chemical substances; in contact lens optics, the absorption of water by contact lens materials
Hydroxypropylmethyl cellulose (HPMC)
Chemical compound used in contact lens care products and eye drops as an additive to increase viscosity
Hypopyon
Pus in the anterior chamber of the eye
Hypotonic solution
Solution with lower salt content than is found in an isotonic solution
Hyperaemia
Increased blood flow to bodily tissue
Heterophoria
Latent strabismus (tendency of the eyes to deviate from the parallel)
Heat disinfection
Method of disinfecting contact lenses using heat; is no longer used today
Hydrophilic
Having an affinity for water; readily absorbing or dissolving in water
Hypertonic solution
Solution with a higher salt content than is found in an isotonic solution
hydrogen peroxide (H202)
Chemical substance for disinfection; contained in many contact lens care products
I
intermittent
Appearing from time to time
Iridotomy
Incising or burning (with a laser) a small hole in the iris
incompatible
incompatible
Inverted cilia
Eyelashes that are turned inward
Iris
The coloured, muscular diaphragm that surrounds and controls the size of the pupil
Isotonia
The same number of dissolved particles as in the reference solution (e.g., sodium chloride solution isotonic with tear fluid)
Infiltrate
A substance that has penetrated the tissue
Incompatible
Incompatible, for example with medicines or contact lens solution
Intraocular lens (IOL)
Synthetic lens implanted in the eye
Iridocyclitis
Inflammation of the iris and the ciliary body
Iritis
Inflammation of the iris
Iridectomy
Excision of a section of the iris
L
Lens
An optical element which converges or diverges light; used in reference to the part of the eye that serves this function as well as to corrective lenses used for correcting vision
Levator (palpebrae)
Muscle that lifts the upper eyelid
Lipophilic
Having an affinity for lipids; soluble in lipids
Lid coloboma
Triangular defect with base at the edge of the eyelid, usually on the upper eyelid
Lid closure insufficiency
Incomplete blinking
Lenticular
Special surface geometry in plus lenses to minimize thickness
Leucoma/ leukoma
A dense, white opacity of the cornea
Limbus
Border or edge (usually of the cornea)
Lipids
Fats; components of the tear film; can accumulate on contact lenses (primarily rigid lenses)
Lumen
Interior of a tubular vessel
LIPCOF
Conjunctival folds parallel to the eyelid margin that allow for an assessment of the eye’s level of dehydration
Lysozyme
An enzyme contained in the tear film; the main component of protein deposits on soft contact lenses
Lensmeter/ Focimeter
Device for the optical measurement of spectacles and contact lenses
Lagophthalmus
Inability of the eyelids to close completely
Lipoid
Fat or fat-like substance; “artificial” fats often found in cosmetics that can accumulate on contact lenses via the tear film
Lupus erythematosus
Autoimmune disease which manifests in various organs
M
Marx´sche Linie
Transition between the eyelid and the conjunctiva
Morbus Basedow
Graves' disease; autoimmune condition may include bulging eyes, weight loss and a fast metabolism
Macula corneae
Patchy, densely circumscribed, grayish corneal scarring
Macula lutea
An oval-shaped, pigmented area near the centre of the retina, responsible for central, high-resolution colour vision
Macromolecule
Giant molecule
Microbiocidal
Killing microorganisms
Microorganism
Generic term for bacteria, fungi and viruses
Miosis
Narrowing of the pupil
Monomer
Basic molecules that can join together to form plastics
Mydriasis
Widening of the pupil
Myectomy
Surgical shortening of a muscle
Maddox
Proper noun; instrument used to measure strabismus (heterophoria)
MAA
Methacrylic acid, a hydrophilic monomer in hydrogel lenses with medium to high-water content
Metamorphopsia
A vision disorder in which the environment appears distorted, straight lines appear curved, etc.
Miotic
A drug that causes miosis
Mononucleosis
Viral infection by the Epstein-Barr virus, also called glandular fever
mouches volantes
Mosquito vision, perception of small opacities due to structural changes in the vitreous body
Mydriatic
Drug that causes the pupil to widen
Micelle
Spatial arrangement of surfactant molecules in an aqueous solution (hydrophilic groups orient themselves outward in an aqueous solution, hydrophobic groups orient themselves inward)
Multifocal
Progressive spectacle lenses or contact lenses with multiple focal distances to correct presbyopia
MDD
Meibom Drüsen Dysfunktion
Monoculus
Patient with only one functioning eye
Mucin
Mucus, component of the tear film
MGD - Meibomian Gland Dysfunktion
Posterior blepharitis; chronic, diffuse disorder of the meibomian glands; characterized by blockage of the excretory duct and/or by qualitative or quantitative changes in glandular secretion
Monovision
Correction of presbyopia by using individual contact lens strengths: one eye is corrected for nearsightedness, the leading eye is corrected for farsightedness
O
OU
Oculus utriusque, both eyes
Ovariectomy
Surgical removal of an ovary or ovaries
Obliquus
Slanting, oblique
OD
Oculus dexter, the right eye
Office eye syndrome
Symptoms of dry eyes disease when working at a computer screen
Optic atrophy
Partial or total atrophy of the optic nerve
Orbita
Orbital cavities; eye sockets
OS
Oculus sinister, the left eye
Ovulation inhibitor, anovulant
Product that protects against conception (see contraceptive)
Oculomotor nerve (nervus oculomotorius)
3rd cranial nerve, innervates several eye muscles
o.B.
unremarkable; without findings; normal condition
Oedema
Fluid deposit in tissue and the swelling associated with it
Occlusion
Covering, closure
Ophthalmometer
Optical instrument for measuring corneal radii
Optic nerve (nervus opticus)
2nd cranial nerve, sensory, supplies the retina
Orthoptic
Relating to normal binocular vision, exercises for normal vision
Osmosis
The tendency of a fluid, usually water, to pass through a semipermeable membrane into a solution where the solvent concentration is higher, thus equalizing the concentrations of materials on either side of the membrane
Osmotic pressure
Pressure that forces a solvent through a semipermeable membrane into a concentrated solution by virtue of osmosis
P
Periosteum
A thick, fibrous, two-layered membrane covering the surface of bones
Perimeter
An instrument for examining the visual field
Piggyback system
Rigid gas permeable contact lenses on a soft carrier lens, e.g. for keratoconus
Perimetry
Assessment of the visual field
Panophthalmia
Inflammation of the entire eye
Papilloma
Benign, wart-shaped tumour
Paralysis
Complete loss of motor function (of a nerve)
Paresis
Partial paralysis
Pathogen
Disease-producing agent
Phoria
Latent (hidden) strabismus
Phlyctaene
Inflamed nodule at the edge of the cornea
Permeable
Pervious /Porous
Physiology
The branch of science concerned with the normal functioning of life processes and the organism
Pinguecula
A yellowish spot on the corneal conjunctiva in the area of the palpebral fissure
Pleoptics
Exercises to treat amblyopia
Polyhexanide
Another designation for PHMB
Polymorphism
In the context of corneal disorders, dissolution of the hexagonal cell bond structure of the cornea
Polyquad
Another designation for polyquaternium-1
ppm
Abbreviation for “parts per million”
Prophylactic
Preventative
Ptosis
Drooping of an organ or part of the body, especially the upper eyelid
Pupils
The apparently black circular apertures at the centre of the eye, through which light passes to the retina
PVP - Polyvinylpyrrolidone
a chemical compound and component in soft contact lenses
Pars plana (retinae)
Most anterior portion of the retina
Preservatives
Chemical compounds used for preserving (e.g. thiomersal, benzalkonium chloride)
Pathological
Caused by or involving disease
Photophobia
Abnormal sensitivity or intolerance of the eyes to light
Proliferation
Rapid growth or increase in numbers
Preservation
Maintaining a condition of low microbial contamination (growth retardant)
Pemphigus
Skin disease characterized by groups of blisters
Papain
Botanical enzyme used to remove protein deposits from contact lenses
Phoropter
Optical instrument to determine refraction
Periphlebitis
Inflammation of the outer coat of a vein and the tissue surrounding it
Prevalence
Frequency of disease or symptom in a population at a some point in time
Proteolysis
Breakdown of proteins into amino acids, such as by enzymes
Presbyopia
Age-related diminishment of ability to focus sharply at close proximity
PMMA
Polymethyl methacrylate (plexiglass, acrylic glass); the first plastic used to manufacture contact lenses
Polymegathism
A greater than normal variation in the size and shape of the corneal epithelial cells, which are barely capable of regeneration
Polymerization
Technical process in which many monomers are linked to form a polymer (such as through UV radiation)
Polyquaternium-1
Chemical compound used as a disinfectant and preservative
Precipitates
In ophthalmology, substances deposited on the posterior surface of the cornea
Proteases
Enzymes that cause the breakdown of proteins, used in contact lens hygiene to remove proteins
Pterygium
Abnormal triangular mass of thickened conjunctiva extending over the cornea and interfering with vision
Pannus
Growth of blood vessels into the cornea
Phthisis (bulbi)
Wasting away (of the eyeball)
Parenchyma
Specific tissue component of an organ
Pancreatin
Pancreatic enzyme mixture, used in contact lens hygiene to remove protein deposits
PAPB - Polyhexamethylene biguanide
a chemical compound used as a disinfectant and preservative in contact lens hygiene
Papillae formation
Polygonal bulge in the conjunctiva surrounding a blood vessel, generally found in the upper tarsal conjunctiva
Phosphene
A sensation of light caused by excitation of the retina by mechanical or electrical means rather than by light
pH value
Degree of acidity or alkalinity (pH 7 = neutral, <7 = acid, >7 = alkaline)
Physiological saline solution
A 0.9% saline solution; corresponds to the salt content of the tear film; used in contact lens hygiene in preserved and unpreserved form as a rinse and to dissolve enzyme tablets
Polymer
A chemical compound (macromolecule) made of many linked smaller molecules (monomers)
Protein
Protein - macromolecules consisting of amino acids (carbon, hydrogen, oxygen, nitrogen and sulphur)
Pseudophakia
An eye with an (implanted) artificial lens (IOL = intraocular lens)
PVA - Polyvinyl alcohol
a chemical compound used in contact lens care as a moistening component; also a component in contact lenses (e.g. Focus Dailies)
S
Spasm
Cramp; excessive (muscle) activity
Schirmer test
Proper noun; test to measure amounts of tears
Silicone-MMA copolymer
Group of materials used to manufacture rigid contact lenses
Sine (correctione)
Without (correction)
Scleritis
Inflammation of the sclera
Sorbic acid
Chemical compound; preservative
Staphyloma
Pathological bulging of the cornea or sclera
Subtarsal
Under the eyelid
Stroma
The connective tissue framework of an organ
Symptom
Sign of an illness
Syndrome
Complex of multiple symptoms
Stereopsis
Depth perception, depth vision
sursumvergens
elevated (for strabismus)
Surface cleaner
Substance (e.g. surfactants) for the removal of organic deposits on contact lenses
Senile dementia
Degenerative changes to the brain in old age
Sjögren's syndrome
Autoimmune disease affecting the moisture-producing glands of the body; causes dry eyes and dry mouth; associated with Sicca syndrome and polyarthritis
Sclera
A dense, white, fibrous membrane that, with the cornea, forms the external covering of the eyeball
Scleroderma
Autoimmune disease affecting the vascular and connective tissue systems
Stenosis
Constriction or narrowing of a passage or vessel
Stevens-Johnson syndrome
Skin disease usually caused by medication or infection
Striae
Primarily vertical, very thin folds or thickenings in deeper stromal tissue
Synechia
Eye condition where the iris adheres to the cornea (anterior synechia) or crystalline lens (posterior synechia)
Str. concommitans convergens
convergent, concomitant strabismus
Staining
Appearance of tissue disruption and other pathophysiological changes in the anterior eye, typically seen with the aid of fluorescein
Sensitivity
measures the percentage of true positives that are correctly identified as such (e.g. the percentage of sick people correctly identified as such)
Silicone rubber
Material used to manufacture soft contact lenses (highest oxygen permeability)
Solubilization
To make soluble; in contact lens care, deposits on contact lenses are made water-soluble via formation of micelles
Specificity
measures the proportion of true negatives that are correctly identified as such (e.g. the proportion of healthy people who are correctly identified as not being ill)
Strabismus
Visual defect in which one eye cannot focus with the other on an objective because of an imbalance of the muscles
Subtilisins
Proteolytic enzymes that display their maximum proteolytic effectiveness in hydrogen peroxide; used in contact lens hygiene as protein removers
T
Temporal
Toward the temple, i.e. the outside (on the face)
Tension
Pressure, tension
Tortuositas (vasorum)
Twisted in shape (of the blood vessels)
Trabecular meshwork
Area in the iridocorneal angle where the aqueous humour drains from the anterior chamber
Tranquilizer
Sedative or calming drug
Tyndall effect
Visibility of beams of light in a colloidal solution
Tonometry
Measurement of (intraocular) pressure
Tenon’s capsule
The bulbar fascia or sheath; the thin membrane that envelops the eyeball and eye muscles
Toxoplasmosis
Parasitic disease caused by toxoplasma gondii that can affect the eyes
Trabeculectomy (trabeculotomy)
Surgical procedure to diminish elevated levels of intraocular pressure
Trachoma
Chronic infection of the conjunctiva and cornea; widespread and much-feared in tropical countries
Trichiasis
Abnormal position of the eyelashes that causes irritation when they rub against the eyeball
Tromethamine
Another term for tris
Trochlear nerve (nervus trochlearis)
4th cranial nerve, innervates the m. obliquus superior
Tensides
Surface-active substances; contained in rich surface cleaners in contact lens hygiene; surfactants are elongated molecules with hydrophilic and hydrophobic ends
Thermal disinfection
See heat disinfection
Thiomersal
Chemical compound used as a preservative, containing mercury
Trabeculoplasty
Laser treatment to diminish elevated levels of intraocular pressure
TRIS - tris(hydroxymethyl)aminomethane
an organic compound used in buffer solutions (C4H11NO3)