Corneal dystrophies were commonly subdivided depending on its specific location within the cornea into "anterior", "stromal", or "posterior" according to the layer of the cornea affected by the dystrophy.

In 2015 the ICD3 classification was published. and has classified disease into four groups as follows:

Epithelial and subepithelial dystrophies

- Epithelial basement membrane dystrophy

- Epithelial recurrent erosion dystrophies (EREDs)—Franceschetti corneal dystrophy, Dystrophia Smolandiensis, and Dystrophia Helsinglandica

- Subepithelial mucinous corneal dystrophy

- Meesmann corneal dystrophy

- Lisch epithelial corneal dystrophy

- Gelatinous drop-like corneal dystrophy

Bowman Layer dystrophies

- Reis–Bücklers corneal dystrophy

- Thiel–Behnke corneal dystrophy

- Stromal dystrophies-

- TGFB1 corneal dystrophies

- Lattice corneal dystrophy, type 1 variants (III, IIIA, I/IIIA, IV) of lattice corneal dystrophy

- Granular corneal dystrophy, type 1

- Granular corneal dystrophy, type 2

Stromal dystrophies

- Macular corneal dystrophy

- Schnyder crystalline corneal dystrophy

- Congenital stromal corneal dystrophy

- Fleck corneal dystrophy

- Posterior amorphous corneal dystrophy

- Central cloudy dystrophy of François

- Pre-Descemet corneal dystrophy

Endothelial dystrophies

- Fuchs' dystrophy

- Posterior polymorphous corneal dystrophy

- Congenital hereditary endothelial dystrophy

- X-linked endothelial corneal dystrophy

The following (now historic) classification was by Klintworth:

Superficial dystrophies:

- Epithelial basement membrane dystrophy

- Meesmann juvenile epithelial corneal dystrophy

- Gelatinous drop-like corneal dystrophy

- Lisch epithelial corneal dystrophy

- Subepithelial mucinous corneal dystrophy

- Reis-Bucklers corneal dystrophy

- Thiel–Behnke dystrophy

Stromal dystrophies:

- Lattice corneal dystrophy

- Granular corneal dystrophy

- Macular corneal dystrophy

- Schnyder crystalline corneal dystrophy

- Congenital stromal corneal dystrophy

- Fleck corneal dystrophy

Posterior dystrophies:

- Fuchs' dystrophy

- Posterior polymorphous corneal dystrophy

- Congenital hereditary endothelial dystrophy

The initial retinal degenerative symptoms of retinitis pigmentosa are characterized by decreased night vision (nyctalopia) and the loss of the mid-peripheral visual field. The rod photoreceptor cells, which are responsible for low-light vision and are orientated in the retinal periphery, are the retinal processes affected first during non-syndromic forms of this disease. Visual decline progresses relatively quickly to the far peripheral field, eventually extending into the central visual field as tunnel vision increases. Visual acuity and color vision can become compromised due to accompanying abnormalities in the cone photoreceptor cells, which are responsible for color vision, visual acuity, and sight in the central visual field. The progression of disease symptoms occurs in a symmetrical manner, with both the left and right eyes experiencing symptoms at a similar rate.

A variety of indirect symptoms characterize retinitis pigmentosa along with the direct effects of the initial rod photoreceptor degeneration and later cone photoreceptor decline. Phenomena such as photophobia, which describes the event in which light is perceived as an intense glare, and photopsia, the presence of blinking or shimmering lights within the visual field, often manifest during the later stages of RP. Findings related to RP have often been characterized in the fundus of the eye as the "ophthalamic triad". This includes the development of (1) a mottled appearance of the retinal pigment epithelium (RPE) caused by bone spicule formation, (2) a waxy appearance of the optic nerve, and (3) the attentuation of blood vessels in the retina.

Non-syndromic RP usually presents a variety of the following symptoms:

- Night blindness

- Tunnel vision (due to loss of peripheral vision)

- Latticework vision

- Photopsia (blinking/shimmering lights)

- Photophobia (aversion to glare)

- Development of bone spicules in the fundus

- Slow adjustment from dark to light environments and vice versa

- Blurring of vision

- Poor color separation

- Loss of central vision

- Eventual blindness

Main differential diagnosis include various causes of monoclonal gammopathy, lecithin-cholesterol-acyltransferase deficiency, Fabry disease, cystinosis, tyrosine transaminase deficiency, systemic lysosomal storage diseases, and several skin diseases (X-linked ichthyosis, keratosis follicularis spinolosa decalvans).

Historically, an accumulation of small gray variable shaped punctate opacities of variable shape in the central deep corneal stroma immediately anterior to Descemet membrane were designated deep filiform dystrophy and cornea farinata because of their resemblance to commas, circles, lines, threads (filiform), flour (farina) or dots. These abnormalities are now known to accompany X-linked ichthyosis, steroid sulfatase deficiency, caused by steroid sulfatase gene mutations and are currently usually not included under the rubric of the corneal dystrophies.

In the past, the designation vortex corneal dystrophy (corneal verticillata) was applied to a corneal disorder characterized by the presence of innumerable tiny brown spots arranged in curved whirlpool-like lines in the superficial cornea. An autosomal dominant mode of transmission was initially suspected, but later it was realized that these individuals were affected hemizygous males and asymptomatic female carriers of an X-linked systemic metabolic disease caused by a deficiency of α-galactosidase, known as Fabry disease.

Patients with Reis-Bücklers dystrophy develop a reticular pattern of cloudiness in the cornea. This cloudiness, or opacity, usually appears in both eyes (bilaterally) in the upper cornea by 4 or 5 years of age. The opacity elevates the corneal epithelium, eventually leading to corneal erosions that prompt attacks of ocular hyperemia, pain, and photophobia. These recurrent painful corneal epithelial erosions often begin as early as 1 year of age.

With time, the corneal changes progress into opacities in Bowman's membrane, which gradually becomes more irregular and more dense. Significant vision loss may occur. However, vascularization of the cornea is not present.

Vitelliform macular dystrophy causes a fatty yellow pigment (lipofuscin) to build up in cells underlying the macula. The retinal pigment epithelium also degenerates. Over time, the abnormal accumulation of this substance can damage the cells that are critical for clear central vision. As a result, people with this disorder often lose their central vision and may experience blurry or distorted vision, and loss is rarely symmetric. Scotomata appear, first with red light and then for green; finally, relative (or in more serious cases, absolute) scotomata occur with white light. Vitelliform macular dystrophy does not affect side (peripheral) vision or the ability to see at night.

Researchers have described two forms of vitelliform macular dystrophy with similar features. The early-onset form (known as Best disease) usually appears in childhood; however, the onset of symptoms and the severity of vision loss vary widely. The adult-onset form begins later, usually in middle age, and tends to cause relatively mild vision loss. The two forms of vitelliform macular dystrophy each have characteristic changes in the macula that can be detected during an eye examination.

Vitelliform macular dystrophy or vitelliform dystrophy is an irregular autosomal dominant eye disorder which can cause progressive vision loss. This disorder affects the retina, specifically cells in a small area near the center of the retina called the macula. The macula is responsible for sharp central vision, which is needed for detailed tasks such as reading, driving, and recognizing faces. The condition is characterized by yellow (or orange), slightly elevated, round structures similar to the yolk (Latin "vitellus") of an egg.

Onset occurs in the first decade, usually between ages 5 and 9. The disorder is progressive. Minute, gray, punctate opacities develop. Corneal sensitivity is usually reduced. Painful attacks with photophobia, foreign body sensations, and recurrent erosions occur in most patients. Macular corneal dystrophy is very common in Iceland and accounts for almost one-third of all corneal grafts performed there.

RP may be:

(1) Non-syndromic, that is, it occurs alone, without any other clinical findings,

(2) Syndromic, with other neurosensory disorders, developmental abnormalities, or complex clinical findings, or

(3) Secondary to other systemic diseases.

- RP combined with deafness (congenital or progressive) is called Usher syndrome.

- Alport's syndrome is associated with RP and an abnormal glomerular-basement membrane leading nephrotic syndrome and inherited as X-linked dominant.

- RP combined with ophthalmoplegia, dysphagia, ataxia, and cardiac conduction defects is seen in the mitochondrial DNA disorder Kearns-Sayre syndrome (also known as Ragged Red Fiber Myopathy)

- RP combined with retardation, peripheral neuropathy, acanthotic (spiked) RBCs, ataxia, steatorrhea, is absence of VLDL is seen in abetalipoproteinemia.

- RP is seen clinically in association with several other rare genetic disorders (including muscular dystrophy and chronic granulomatous disease) as part of McLeod syndrome. This is an X-linked recessive phenotype characterized by a complete absence of XK cell surface proteins, and therefore markedly reduced expression of all Kell red blood cell antigens. For transfusion purposes these patients are considered completely incompatible with all normal and K0/K0 donors.

- RP associated with hypogonadism, and developmental delay with an autosomal recessive inheritance pattern is seen with Bardet-Biedl syndrome

Other conditions include neurosyphilis, toxoplasmosis and Refsum's disease.

Patients with Stargardt disease usually develop symptoms in the mid-first to the late second decade of life, with age of onset which can be as early as ~6 years of age. The main symptom of Stargardt disease is loss of visual acuity, uncorrectable with glasses, which progresses and frequently stabilizes between 20/200 and 20/400. Other symptoms include wavy vision, blind spots (scotomata), blurriness, impaired color vision, and difficulty adapting to dim lighting (delayed dark adaptation). The disease sometimes causes sensitivity to glare; overcast days offer some relief. Vision is most noticeably impaired when the macula (center of retina and focus of vision) is damaged, leaving peripheral vision more intact. Generally, vision loss starts within the first 20 years of life.

Examination with an ophthalmoscope shows few notable findings in the early stages of the disease. Eventually, however, an oval-shaped atrophy with a horizontal major axis appears in the retinal pigment epithelium, and has the appearance of beaten bronze, along with sparing of the area surrounding the optic disc (peripapillary sparing). Techniques such as fundus autofluorescence (FAF), Optical Coherence Tomography (OCT), or less frequently fluorescein angiography, can detect early signs before they are visible ophthalmoscopically.

Since the "CHM" gene is located on the X chromosome, symptoms are seen almost exclusively in men. While there are a few exceptions, female carriers have a noticeable lack of pigmentation in the RPE but do not experience any symptoms. Female carriers have a 50% chance of having either an affected son or a carrier daughter, while a male with choroideremia will have all carrier daughters and unaffected sons.

Even though the disease progression can vary significantly, there are general trends. The first symptom many individuals with choroideremia notice is a significant loss of night vision, which begins in youth. Peripheral vision loss occurs gradually, starting as a ring of vision loss, and continuing on to "tunnel vision" in adulthood. Individuals with choroideremia tend to maintain good visual acuity into their 40s, but eventual lose all sight at some point in the 50-70 age range. A study of 115 individuals with choroideremia found that 84% of patients under the age of 60 had a visual acuity of 20/40 or better, while 33% of patients over 60 years old had a visual acuity of 20/200 or worse. The most severe visual acuity impairment (only being able to count fingers or worse) did not occur until the seventh decade of life. The same study found the rate of visual acuity loss to be about 1 eye chart row per 5 years.

Clinically, there is an acute onset of visual loss, first in one eye, and then a few weeks to months later in the other. Onset is usually young adulthood, but age range at onset from 7-75 is reported. The age of onset is slightly higher in females (range 19–55 years: mean 31.3 years) than males (range 15–53 years: mean 24.3). The male to female ratio varies between mutations: 3:1 for 3460 G>A, 6:1 for 11778 G>A and 8:1 for 14484 T>C.

This typically evolves to very severe optic atrophy and a permanent decrease of visual acuity. Both eyes become affected either simultaneously (25% of cases) or sequentially (75% of cases) with a median inter-eye delay of 8 weeks. Rarely only one eye may be affected. In the acute stage, lasting a few weeks, the affected eye demonstrates an edematous appearance of the nerve fiber layer especially in the arcuate bundles and enlarged or telangiectatic and tortuous peripapillary vessels (microangiopathy). The main features are seen on fundus examination, just before or subsequent to the onset of visual loss. A pupillary defect may be visible in the acute stage as well. Examination reveals decreased visual acuity, loss of color vision and a cecocentral scotoma on visual field examination.

Reis-Bücklers corneal dystrophy, also known as corneal dystrophy of Bowman layer, type I, is a rare, corneal dystrophy of unknown cause, in which the Bowman's layer of the cornea undergoes disintegration. The disorder is inherited in an autosomal dominant fashion, and is associated with mutations in the gene TGFB1.

Reis-Bücklers dystrophy causes a cloudiness in the corneas of both eyes, which may occur as early as 1 year of age, but usually develops by 4 to 5 years of age. It is usually evident within the first decade of life. This cloudiness, or opacity, causes the corneal epithelium to become elevated, which leads to corneal opacities. The corneal erosions may prompt attacks of redness and swelling in the eye (ocular hyperemia), eye pain, and photophobia. Significant vision loss may occur.

Reis-Bücklers dystrophy is diagnosed by clinical history physical examination of the eye. Labs and imaging studies are not necessary. Treatment may include a complete or partial corneal transplant, or photorefractive keratectomy.

Oguchi disease present with nonprogressive night blindness since young childhood or birth with normal day vision, but they frequently claim improvement of light sensitivities when they remain for some time in a darkened environment.

On examination patients have normal visual fields but the fundos have a diffuse or patchy, silver-gray or golden-yellow metallic sheen and the retinal vessels stand out in relief against the background.

A prolonged dark adaptation of three hours or more, leads to disappearance of this unusual discoloration and the appearance of a normal reddish appearance. This is known as the Mizuo-Nakamura phenomena and is thought to be caused by the overstimulation of rod cells.

Other conditions with similar appearing fundi include

- Cone dystrophy

- X-linked retinitis pigmentosa

- Juvenile macular dystrophy

These conditions do not show the Mizuo-Nakamura phenomenon.

There is another retinal disease in Briards known as hereditary retinal dysplasia. These dogs are night blind from birth, and day vision varies. Puppies affected often have nystagmus. It is also known as lipid retinopathy.

Granular corneal dystrophy is diagnosed during an eye examination by an ophthalmologist or optometrist. The lesions consist of central, fine, whitish granular lesions in the cornea. Visual acuity is slightly reduced.

Patients may complain of severe problems with dry eyes, or with visual obscurations. It can also be asymptomatic, and only discovered because of subtle lines and marks seen during an eye exam.

EBMD is a bilateral anterior corneal dystrophy characterized by grayish epithelial fingerprint lines, geographic map-like lines, and dots (or microcysts) on slit-lamp examination. Findings are variable and can change with time. While the disorder is usually asymptomatic, up to 10% of patients may have recurrent corneal erosions, usually beginning after age 30; conversely, 50% of patients presenting with idiopathic recurrent erosions have evidence of this dystrophy.

The most common symptoms of cone dystrophy are vision loss (age of onset ranging from the late teens to the sixties), sensitivity to bright lights, and poor color vision. Therefore, patients see better at dusk. Visual acuity usually deteriorates gradually, but it can deteriorate rapidly to 20/200; later, in more severe cases, it drops to "counting fingers" vision. Color vision testing using color test plates (HRR series) reveals many errors on both red-green and blue-yellow plates.

Filamentous opacities appear in the cornea with intertwining delicate branching processes. During an eye examination, the doctor sees these deposits in the stroma as clear, comma-shaped overlapping dots and branching filaments, creating a lattice effect. Over time, the lattice lines will grow opaque and involve more of the stroma. They will also gradually converge, giving the cornea a cloudiness that may also reduce vision. The disease is bilateral, usually noted before the end of the first decade of life. Although lattice dystrophy can occur at any time in life, the condition usually arises in children between the ages of two and seven.

In some people, these abnormal protein fibers can accumulate under the cornea's outer layer—the epithelium. This can cause erosion of the epithelium. This condition is known as recurrent epithelial erosion. These erosions alter the cornea's normal curvature, resulting in temporary vision problems, and expose the nerves that line the cornea, causing severe pain. Even the involuntary act of blinking can be painful.

In systemic cases, kidney failure, heart failure and neuropathy such as facial nerve palsy, laxity of the skin may be noted.

The main pathological features in this dystrophy are mulberry-shaped gelatinous masses beneath the corneal epithelium. Patients suffer from photophobia, foreign body sensation in the cornea. The loss of vision is severe. The amyloid nodules have been found to contain lactoferrin, but the gene encoding lactoferrin is unaffected.

This form of corneal amyloidosis appears to be more frequent in Japan.

A cone dystrophy is an inherited ocular disorder characterized by the loss of cone cells, the photoreceptors responsible for both central and color vision.

Progressive vision loss in any dog in the absence of canine glaucoma or cataracts can be an indication of PRA. It usually starts with decreased vision at night, or nyctalopia. Other symptoms include dilated pupils and decreased pupillary light reflex. Fundoscopy to examine the retina will show shrinking of the blood vessels, decreased pigmentation of the nontapetal fundus, increased reflection from the tapetum due to thinning of the retina, and later in the disease a darkened, atrophied optic disc. Secondary cataract formation in the posterior portion of the lens can occur late in the disease. In these cases diagnosis of PRA may require electroretinography (ERG). For many breeds there are specific genetic tests of blood or buccal mucosa for PRA.

Absent a genetic test, animals of breeds susceptible to PRA can be cleared of the disease only by the passage of time—that is, by living past the age at which PRA symptoms are typically apparent in their breed. Breeds in which the PRA gene is recessive may still be carriers of the gene and pass it on to their offspring, however, even if they lack symptoms, and it is also possible for onset of the disease to be later than expected, making this an imperfect test at best.

"LHON Plus" is a name given to a rare variant of the disorder with eye disease together with other conditions. The symptoms of this higher form of the disease include loss of the brain's ability to control the movement of muscles, tremors, and cardiac arrhythmia. Many cases of LHON plus have been comparable to multiple sclerosis because of the lack of muscular control.

Granular corneal dystrophy is a slowly progressive corneal dystrophy that most often begins in early childhood.

Granular corneal dystrophy has two types:

- Granular corneal dystrophy type I , also corneal dystrophy Groenouw type I, is a rare form of human corneal dystrophy. It was first described by German ophthalmologist Arthur Groenouw in 1890.

- Granular corneal dystrophy type II, also called Avellino corneal dystrophy or combined granular-lattice corneal dystrophy is also a rare form of corneal dystrophy. The disorder was first described by Folberg et al. in 1988. The name Avellino corneal dystrophy comes from the first four patients in the original study each tracing their family origin to the Italian province of Avellino.

In the recessive form corneal clouding is observed at birth or within the neonatal period, nystagmus is often present, but no photophobia or epiphora is seen. In the autosomal dominant type corneal opacification is usually seen in the first or second year of life and progresses slowly, and nystagmus is infrequently seen.