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INJURIES OF THE EYE IN INFECTIONAL DISEASES

The amount of infectional diseases when the eye is injured is extraordinary great, that is why let's dwell on the most often occurring ones.

Nowadays the viral diseases take an important place in a struc­ture of infectional pathology. The disease of the eyes is mostly called by adenoviruses, viruses of grip, herpes. On the background of injury of the upper airways adenoviral conjunctivitis develops (adenopharingoconjunctival fever). Not rarely recidivating herpetic keratitis arises in the persons, infected by herpetic virus. When her­petic or grip infections inflammatations of choroid develop: irido-cyclites, choroidites, panuveites.

Measles is usually accompanied by catarhal conjunctivitis, which can appear already in the second half of the incubation period. Su­perficial keratitis develops often. In severe cases there are compli­cations in a form of ulceral keratitis, uveitis, retrobulbar neuritis.

In rubella catarhal conjunctivitis, rarely superficial keratitis also take place. In severe cases the complications in a form of panophthalmitis, retinitis are possible. In the women during first 4 months of pregnancy rubella can cause infecting of fetus and development of microphthalmos, inborn cataract and other eye abnormalities.

Chickenpox. Typical vesicular elements can appear on the skin of palpebrae, conjunctiva, in severe cases there are observed ul­ceral keratitis, uveitis, retinitis, optic nerve neuritis.

In infectious mononucleosis besides conjunctiva, cornea, choroid, the peripherical nerves, which innervate the eye, can be injured.

Epidemic parotitis is not rarely accompanied by injury of lacrimal glands — dacryoadenitis, the clinical symptoms of which are oede­ma and hyperemia of the palpebrae and conjunctiva, mostly in the area of lateral angle of the eye, lacrimation, pains in the orbit.

Cytomegalia. Injury of the retina (retinites, secondary retinal detachment) is typical.

Listeriosis (oculoglandular form). Against a background of preauricular and submandibular lymphadenitis there is observed unilateral injury of the eyes in a form of conjunctivitis with mo­derate hyperemia and infiltration mostly of transitional folds of con­junctiva with presence of follicles, sometimes with yellowish gran-ulomae up to 3-5 mm with necrosis in centre. The palpebrae are hyperematous, oedematous. The complications in a form of kera­titis and uveitis occur rarely.

In viral injuries of the eyes frequent instillations of virusostatic preparations (interferon, IDU, DNA-ase), laying of teobrophen or florphenal ointments are indicated. When injury of choroid, retina and optic nerve, symptomatic and pathogenic treatment is pre­scribed.

The Behcet's syndrome — a viral disease with a severe clinical course. There is recidivating iridocyclitis with hypopyon, compli­cated with neuroretinitis, chorioretinitis, periphlebitis of the reti­na, secondary glaucoma. The process is more frequently bilateral and results in blindness. Treatment consists of the use of immuno-supressive agents (cyclophosphan, phthoruracyl) besides of gener­ally used antiinflammatory preparations.



Gonorrhea and diphtheria can cause acute conjunctivitis devel­opment, which is frequently complicated by ulceral keratitis. In the persons suffering from diphtheria on the 3rd-4th week there is pos­sible injury of oculomotor nerves, which results in ptosis, squint, facial paralysis or accomodation (under preservation of pupillar reaction).

The eyes are most frequently affected in toxoplasmosis, tuber­culosis, syphilis among chronic infectional diseases.

In inborn toxoplasmosis chorioretinitis often occurs, as well as anophthalmos, microphthalmos, colobomae of the choroid and optic disc, atrophy of the optic nerve, inborn near-sightedness, cataract. It is also characteristic for acquired toxoplasmosis injury of the posterior area of choroid with inclination to relapse. The treatment is specific and symptomatic.

Tuberculosis causes inflammation of the uveal tract (iridocycli­tis, choroiditis), as well as injury of the cornea and sclera in a form of tuberculo-allergic keratitis, deep infiltration of the cornea, deep scleritis. As a rule only one eye suffers.

Almost all the parts of the eye can be injured when syphilis. In­born syphilis more frequently affects the cornea (parenchymatous keratitis), choroid and retina (chorioretinis with a characteristic picture of fundus of the eye like "salt with pepper"). For the ac­quired syphilis plastic or papular iridocyclitis, gummae of iris, se­rous diffuse choroiditis, dessiminated chorioretinitis, neuritis of the optic nerve are characteristic, in later stages atrophy of the optic nerve occurs.

In 3-6% of patients suffering from rheumatism bilateral uveitis can often develop. Embolism of the central retinal arteria some-tiroes occurs in endocarditis.

Ocular symptomatics plays an important role in diagnosis and con­trol for the dynamics of the process when AIDS. The first ocular symp­tom of the AIDS, the marker of the disease is considered to be cot­ton-like focuses. As a rule, the focuses are numerous with the size more often up to 1/4 of disc diameter, rare 1 disc diameter, from pale-grey or creme to the colour of white bone, they are located pericappilarly in a layer of nerve fibres, no further than 6 diameters from the optic disc. After 1-3 months they recieve a reverse development with re­distribution of pigment. The focuses are dissolving in spite of change of the general condition of patients to the worse.

For the opinion of the majority of researchers, a laying of free-circulating immune complexes in the walls of tiny retinal vessels with following ischemia resulting in aggregation of cytoplasmatic organells in nerve axons plays role in pathogenesis of cotton-like focuses. Being an early AIDS's symptom, cotton-like focuses serve simultaneously also as indicator of poor prognosis of the disease.

Isolated haemorrhages in retina are also concerned to be a symp­tom of "uninfectional retinopathy" when AIDS. Apparently, the main reason of their origin are layers of immune complexes in the walls of vessels and following failing of microcirculation.

Together with common haemorrhages there can be ones which have white centre with semicircle of haemorrhage — these are Rote's spots. Their localization is posterior pole of the eye.

Microaneurisms and teleangioectasias of the retina relate to un­infectional retinopathies, too.

On the top of the disease in the AIDS-patients — manifestations of opportunistic infections are observed. Most frequently, in 40% of the patients, cytomegaloviral retinitis develops. It is the main reason of blindness and poor prognostic sign. In the most patients retinitis begins in the terms from 3 weeks to 20 months after es­tablishing AIDS diagnosis. However, not rarely it can be its first symptom.

Retinitis usually develops on both eyes, under that its course is asimmetrical. It is characterized clinically by appearance of reti­nal necrosis focuses, exudates and haemorrhages, inflammatory muffs along retinal vessels and by steadfast progressing even till retinal destruction.

One can mark 3 stages in retinitis course.

In the initial (serous) stage on the periphery of the fundus of the eye, more rarely in the posterior eye's pole white granulated foci with sharply shaped edges appear. The focuses are double-tri­pled during one month, achieving the size of some disc diameters. Along the way of big vesssels of retina inflammatory muffs and haemorrhages appear. The focuses of injury when retinitis differ from cotton-like focuses by deeper location and characteristic cheese-like granulation.

Later the focuses join together and transform into the second (hemorrhagic) stage. It is characterized by appearance of numer­ous haemorrhages inside of focuses of retinitis and along the way of their frontiers. Profuse haemorrhages are situated perivascularly, reminding occlusion of the central retinal vein. In that stage the fundus of the eye can be compared compared to the ketchup with cheese.

After 2-3 months the disease transforms into the third (atrophi­ca!) stage. White focuses lose their granulation, becoming grey-brown scary focuses with expressed retinal and pigment epitheli­um atrophy. Not rarely atrophy of the optic nerve develops and in the case of the expressed inflammatory reaction — vitreoreti-nal adhesions.

A serious complication of cytomegaloviral retinitis is a retinal detachment, both exudative and rheumatogenic (idiopathic).

They use virusostatic preparations from the group of acyclovir for the treatment of retinitis, however, without a particular suc­cess.

OCULAR MANIFESTATIONS IN DISEASES OF THE NERVOUS

SYSTEM

Ocular symptoms play an important role in diagnosis of diseas­es of the nerve system. The earliest signs of such pathology can be changes of colour perception, narrowing and defects of visual field, failing of visual acuity, metamorphopsy, micro- and macrop-sy, failing of binocular vision, diplopia, change of pupillar size, dis­function of their reaction, failing of convergence as well as chang­es of the fundus of the eye.

Neuroinfections cause paralysis of oculomotor muscles, squint, ptosis, change of pupillar reaction on light, development of neuri­tis of the optic nerve, chorioretinitis. Changes occuring in cerebral abscess are mostly unilateral. Nystagmus is characteristic for cer-eberral abscess.

The tumours, cerebral hydropsy. All the processes accompanied by increasing of intracranial pressure result in development of stag­nant optic papilla, which can transform into atrophy. The earliest functional signs of intracranial hypertension are an increasing of the optic papilla, in case of the optic nerve atrophy the failure of optic functions (untill blindness) occurs.

In disfunction of cerebral blood flow, besides of paralysis of oc­ulomotor muscles and stagnant optic papilla, homonyme hemian-c psies are often observed. In thrombosis of cavernous sinus exoph­thalmos, usually bilateral, ophthalmoplegia, in a number of cases - oedematous papilla, optic neuritis, thrombosis of the central ret-lr al vein develop.

Polymorphism of ocular symptoms is characteristic for neurotrau-raa. Appearance of haemorrhages under the skin of palpebra and un­der conjunctiva of the eyeball after some days after trauma (specta­cles symptom) indicate fracture of cranial basis. Symptom of supe­rior orbital fissura (ptosis, exophthalmos, total ophthalmoplegia, fai­ling of sensitivity along the way of the 1st branch of the trigeminal nerve, haemorrhages on the fundus of the eye) can also develop.

Spinal syphilis and progressive paralysis. The earliest symptoms are anisocoria, absence of pupillar response to light under conser­vation of it on convergence and accomodation (the Argile — Robertson's symptom). Then common atrophy of the optic nerve develops, ophthalmoplegia can be observed.

Disseminated sclerosis begins with neuritis of the optic nerve in 20% of cases. The sight under influence of the treatment is usually recovered, but the disease recurs and atrophy of the optic nerves develops gradually.

The diseases of peripheric nerves are accompanied by ocular symp-tomatics too. So, in neuritis of the trigeminal nerve neuroparalitic kera­titis often takes place. Ptosis, myosis and enophthalmos are charac­teristic for paralysis of the sympathetic nerve (the Horner's symp­tom).


Date: 2015-02-03; view: 1399


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