DISEASES OF THE DISEASES OF THE UVEAL TRACTUVEAL TRACT

UVEAL TRACTUVEAL TRACT The middle vascular The middle vascular

layer of the eye, the layer of the eye, the uveal tract, is uveal tract, is composed of three composed of three portions: iris, ciliary portions: iris, ciliary body, and choroid. body, and choroid. The primary function The primary function of this tract is to of this tract is to supply nourishment supply nourishment to the ocular to the ocular structures.structures.

Congenital anomalies of uveal tract.Congenital anomalies of uveal tract.

Congenital Congenital colobomacoloboma (absense (absense of tissue) of iris, of tissue) of iris, ciliary body and ciliary body and choroid may be choroid may be seen in association seen in association or independently. or independently.

Congenital anomalies of uveal tract.Congenital anomalies of uveal tract.

Congenital aniridia.Congenital aniridia. It refers to It refers to congenital absence congenital absence of iris.of iris.

PolycoriaPolycoria is a is a condition, when condition, when there are more there are more than one pupil.than one pupil.

Inflammatory diseases of the uveal tractInflammatory diseases of the uveal tract Uveitis is a general Uveitis is a general

term reffering to term reffering to inflammation of the inflammation of the uveal tract. It may uveal tract. It may be divided into be divided into iritis, cyclitis iritis, cyclitis (ciliary body (ciliary body inflammation), inflammation), iridocyclitis and iridocyclitis and choroiditis, choroiditis, according to according to specific areas of the specific areas of the uveal tract involveduveal tract involved

Anatomical classificationAnatomical classification includes:includes:

1) Anterior uveitis. It is inflammation 1) Anterior uveitis. It is inflammation of the uveal tissue from the iris up to of the uveal tissue from the iris up to pars plicata of ciliary body. This term pars plicata of ciliary body. This term includes iritis, iridocyclitis and includes iritis, iridocyclitis and anterior cyclitisanterior cyclitis

2) Intermediate uveitis. It includes 2) Intermediate uveitis. It includes inflammation of the pars plana and inflammation of the pars plana and peripheral part of the retina.peripheral part of the retina.

3) Posterior uveitis. It refers to 3) Posterior uveitis. It refers to inflammation of the choroid inflammation of the choroid (choroiditis). (choroiditis).

4) Panuveitis is inflammation of the 4) Panuveitis is inflammation of the whole uvea.whole uvea.

Clinical classificationClinical classification

Acute uveitis Acute uveitis Chronic uveitisChronic uveitis

MorphologicallyMorphologically classificationclassification

Granulomatous uveitisGranulomatous uveitis Nongranulomatous uveitisNongranulomatous uveitis

Etiological classification.Etiological classification.

Exogenous uveitis. Exogenous uveitis Exogenous uveitis. Exogenous uveitis is caused by either external injury to is caused by either external injury to the uvea by invasion of the uvea by invasion of microorganisms or other agents from microorganisms or other agents from outside.outside.

Endogenous uveitis. Endogenous Endogenous uveitis. Endogenous uveitis is-caused by microorganisms uveitis is-caused by microorganisms or other agents from within the or other agents from within the patient. patient.

Anterior uveitis (iridocyclites).Anterior uveitis (iridocyclites).

The main The main symptomssymptoms of acute anterior of acute anterior uveitisuveitis are are

photophobia, photophobia, pain, pain, lacrimation and lacrimation and blepharospasm. blepharospasm.

Pain is dominating symptom of acute Pain is dominating symptom of acute anterior uveitis. Patients usually complain anterior uveitis. Patients usually complain of a dull aching throbbing sensation which of a dull aching throbbing sensation which is typically worse at night. is typically worse at night.

Objective signs of iridocyclitis:Objective signs of iridocyclitis:

mild lid mild lid oedema, oedema,

pericorneal or pericorneal or mixed mixed injectioninjection,,

ciliary pain.ciliary pain.

Corneal signs:Corneal signs: Keratic Keratic

precipitates are precipitates are cellular deposits cellular deposits on the corneal on the corneal endothelium. endothelium.

Fresh keratic Fresh keratic precipitates tend precipitates tend to be white and to be white and round. With age round. With age they shrink, fade they shrink, fade and become and become pigmented.pigmented.

Anterior chamber:Anterior chamber: Changes in aqueous Changes in aqueous

humour are an early sign humour are an early sign of active inflammation.of active inflammation.

Aqueous flare is the Aqueous flare is the result of leakage of result of leakage of proteins into the proteins into the aqueous humour aqueous humour through damaged iris through damaged iris blood vessels and blood vessels and necessarily indicative of necessarily indicative of active inflammation.active inflammation.

Anterior chamber:Anterior chamber: Hypopion (sterile pus Hypopion (sterile pus

in the anterior in the anterior chamber). Exudates chamber). Exudates settle down in lower settle down in lower part of the anterior part of the anterior chamber.chamber.

Hyphaema (blood in Hyphaema (blood in the anterior chamber) the anterior chamber) may be seen in may be seen in haemorrhagic type of haemorrhagic type of uveitis.uveitis.

Iris.Iris. Loss of normal Loss of normal

pattern occurs due pattern occurs due to oedema and to oedema and water logging of iris water logging of iris

Iris usually Iris usually becomes muddy in becomes muddy in colour during active colour during active phase and may phase and may show show hyperpigmented hyperpigmented and depigmented and depigmented areas in healed areas in healed stage. stage.

Iris.Iris. Posterior synechia are Posterior synechia are

adhesions between the adhesions between the posterior surface of iris and posterior surface of iris and anterior capsule of anterior capsule of crystalline lens. These are crystalline lens. These are formed due to organisation formed due to organisation of the fibrin, which is of the fibrin, which is profuse in exudates. profuse in exudates. Posterior synechia may be Posterior synechia may be segmental, annular or total. segmental, annular or total. Segmental posterior Segmental posterior synechia refers to adhesions synechia refers to adhesions of iris to the lens at some of iris to the lens at some points; annular posterior points; annular posterior synechia - ring synechia are synechia - ring synechia are 360° (seclusio pupillae).360° (seclusio pupillae).

Pupillary signsPupillary signs Total posterior synechia due to plastering of Total posterior synechia due to plastering of

total of iris with the anterior capsule of lens total of iris with the anterior capsule of lens (occlusio pupillae).(occlusio pupillae).

Narrow pupil occurs in acute attack of Narrow pupil occurs in acute attack of iridocyclitis due to irritation of sphincter iridocyclitis due to irritation of sphincter pupillae by toxins. pupillae by toxins.

Irregular pupil shape results from segmental Irregular pupil shape results from segmental posterior synechia formation. Dilatation of posterior synechia formation. Dilatation of pupil with atropine at this stage results in pupil with atropine at this stage results in festooned pupil. festooned pupil.

Anterior vitreous may show exudates and Anterior vitreous may show exudates and inflammatory cells after an attack of acute inflammatory cells after an attack of acute iridicyclitis.iridicyclitis.

Complications.Complications. Complicated cataract. Complicated cataract. Keratopathy (degeneration of Keratopathy (degeneration of

the cornea)the cornea) Secondary glaucoma. Secondary glaucoma. Retinal complications include Retinal complications include

cystoid macular oedema, macula cystoid macular oedema, macula degeneration and exudative degeneration and exudative retinal detachmentretinal detachment

Complications.Complications.

Papillitis (inflammation of the Papillitis (inflammation of the optic disc)optic disc)

Phthisis buibi - is the final stage Phthisis buibi - is the final stage of any form of chronic uveitisof any form of chronic uveitis. .

Acute iridocyclitis must be Acute iridocyclitis must be differentiated from other causes differentiated from other causes of acute red eye, especially of acute red eye, especially acute congestive glaucoma.acute congestive glaucoma.

Treatment of iridocyclitis.Treatment of iridocyclitis. Mydriatic-cycloplegic drugs. Commonly Mydriatic-cycloplegic drugs. Commonly

used drug is 1% atropine sulfate, 2% used drug is 1% atropine sulfate, 2% homatropine, 1% cyclopentolate eye drops homatropine, 1% cyclopentolate eye drops instilled 2-4 times a day.instilled 2-4 times a day.

Corticosteroids are very effective. They Corticosteroids are very effective. They reduce inflammation by their anti-reduce inflammation by their anti-inflammatory effect; being anti-allergic inflammatory effect; being anti-allergic (dexamethasone, betamethasone, (dexamethasone, betamethasone, hydrocortisone or prednisolone). Locally hydrocortisone or prednisolone). Locally steroids are used as eye drops 4-6 times a steroids are used as eye drops 4-6 times a day, subconjunctival njections.day, subconjunctival njections.

Broad spectrum antibiotics (in form of Broad spectrum antibiotics (in form of drops and subconjunctival injection)drops and subconjunctival injection)

Posterior Posterior uveitis. (Choroiditis)uveitis. (Choroiditis)

Etiology and pathologyEtiology and pathology are the are the same as for uveitis in general. same as for uveitis in general. Choroiditis is a painless condition, Choroiditis is a painless condition, usually characterized by visual usually characterized by visual symptoms due to associated vitreous symptoms due to associated vitreous haze and involvement of the retina. haze and involvement of the retina.

SymptomsSymptoms floaters and impaired visionfloaters and impaired vision photopsiaphotopsia metamorphopsiametamorphopsia

Posterior Posterior uveitis. (Choroiditis)uveitis. (Choroiditis)SignsSigns Choroiditis is characterized by yellow or Choroiditis is characterized by yellow or

greyish patches with reasonably well-greyish patches with reasonably well-demarcated borders. demarcated borders.

The overlying retina is often cloudy and The overlying retina is often cloudy and oedematous. oedematous.

In atrophic stage, when active In atrophic stage, when active inflammation subsides, the affected area inflammation subsides, the affected area becomes more sharply defined and becomes more sharply defined and delineated from the rest of the normal delineated from the rest of the normal area. The involved area shows white sclera area. The involved area shows white sclera below the atrophic choroid and black below the atrophic choroid and black pigmented clumps at the periphery of the pigmented clumps at the periphery of the lesion.lesion.

Tumours of the uveal tract.Tumours of the uveal tract.

Benign tumors:Benign tumors: neurofibroma, neurofibroma, leiomyoma, benign cysts, leiomyoma, benign cysts, naevus, haemangioma.naevus, haemangioma.

Malignant melanomasMalignant melanomas are the are the most frequently occurring most frequently occurring intraocular tumours in adults.intraocular tumours in adults.

Malignant melanomasMalignant melanomas

Clinical pictureClinical picture: In : In typical cases typical cases examination shows a examination shows a pigmented elevated, pigmented elevated, oval-shaped mass. The oval-shaped mass. The colour of the tumor is colour of the tumor is frequently brown or frequently brown or black. A secondary black. A secondary exudative detachment exudative detachment of the overlying sensory of the overlying sensory retina may develop. retina may develop.

Treatment:Treatment: Enucleation (excision of the globe) Enucleation (excision of the globe) Radioactive plaques are suitable for small Radioactive plaques are suitable for small

tumours and medium-size tumourstumours and medium-size tumours Photocoagulation with xenon arc or argon Photocoagulation with xenon arc or argon

laser may be used for treatment of laser may be used for treatment of melanomes of choroidmelanomes of choroid

Partial lamellar sclerouvectomy may be Partial lamellar sclerouvectomy may be suitable for certain carefully selected suitable for certain carefully selected tumours.tumours.

Exenteration is indicated for melanomas Exenteration is indicated for melanomas with extensive extraocular extensionwith extensive extraocular extension