Download The uveal tract

The uveal tract
Nicolette Sohar
Department of Ophthalmology,
University of Szeged
The uveal tract:
Iris
Ciliary body
Choroid
Vascular supply: ophthalmic artery, short
posterior ciliary arteries, long posterior
ciliary arteries, anterior ciliary arteries,
vorticose or vortex veins
Sensory supply: long and short ciliary
nerves
Iris
Structure: anterior mesodermal stromal layer
posterior ectodermal pigmented
epithelial layer
Collarette of the iris: pupillary and ciliary
part
Surface: crypts and trabeculae
Color: melanin content of the melanocytes
Examination methods: slit lamp (Tyndall
effect, cells), gonioscopy,
Developmental anomalies
Aniridia: bilateral,
autosomal dominant or sporadical,
traumatic
Associated with: foveal hypoplasia,
nystagmus, amblyopia, buphthalmos, cataract
Coloboma: incomplete fusion of the
embryonic optic cup
in about the sixth week of pregnancy
medially and inferiorly directed
iris, ciliary body, zonule fibers, choroid, optic nerve
Pigmentation anomalies
Iris bicolor: one iris containing varying
pigmentation
Heterochromia: congenital difference in
coloration between the left and right iris
Fuchs`heterochromic cyclitis: recurrent
iridocyclitis (precipitates, cataract, glaucoma)
Sympathetic: unilateral impairment of the
sympathetic nerve supply (affected – lighter)
Melanosis: dark pigmentation of the iris
Albinism: metabolic disease that leads
to hypopigmentation of the eye
ocular: only the eyes
oculocutaneous: eyes, skin and hair
iris is light blue
choroidal vessels detectable
reduction in visual acuity
photophobia
nystagmus
Inflammation
1. Acute iritis and iridocyclitis:
Symptoms: dull pain, impaired vision,
photophobia, excessive tearing
Etiology: immunologic causes,
HLA-B27associated,
symptom of systemic disease
infections
HLA-B27 associated:idiopathic
ankylosing
spondylitis
Reiter`s syndrome
regional enteritis
ulcerative colitis
psoriasis
Non-HLA-B27 associated: idiopathic
viral
tuberculosis
sarcoidosis
syphilis
leprosy
RA
heterochromic
iridocyclitis
phacogen uveitis
trauma
Ophthalmic picture:
-ciliary injection
-combined injection
-diffuse structure and reactive miosis
-cellular infiltration of the anterior
chamber and protein or fibrin
accumulation
-precipitates
-hypopyon
-hyphaema
Complications:
Secondary open angle glaucoma
Anterior synechiae
Posterior synechiae
Differential diagnosis of iritis and acute
glaucoma
Differential
criteria
Acute iritis
Acute glaucoma
Symptoms
Dull pain,
photophobia
Intense pain and
vomiting
Conjunctiva
Combined injection Combined injection
Cornea
Clear
Anterior chamber
Pupil
Normal depth;
cells and fibrin
Narrowed
Globe
Normal pressure
Opacified,
edematosus
Shallow
Dilated, not round
Rock hard
Treatment:
topical
systemic
antibiotic or antiviral
due to a pathogen
therapeutic mydriasis (atropin,scopolamin
cyclopentolate, epinephrine)
steroid therapy- topical (prednisolon)
subconj.(dexamethason)
where no pathogen
Secondary open angle glaucoma:
beta blockers
carbonic anhydrase inhibitors
Prognosis:
Symptoms usually improve within a
few days when proper therapy is initiated.
The disorder can progress to a
chronic stage.
2. Chronic iritis and iridocyclitis:
Epidemiology: one quarter of all iridocyclitis have a
chronic clinical course
Symptoms: may exhibit minimal symptoms
Ophthalmic picture: like acute iridocyclitis
Differential diagnosis: acute glaucoma,
conjunctivitis, keratitis
Complications:
Pupillary block- obliteration of the pupil by
posterior synechiae
Secondary angle closure glaucoma with
`iris bombe`
Calcific band keratopathy
Occlusion of the pupil
Fibrous scarring in the pupil
posterior subcapsular opacities
secondary cataract
Treatment:
in pupillary block – Nd: YAG laser
iridotomy
secondary cataract – cataract extraction
Prognosis:
may progress to blindness from
shrinkage of the eyeball
Rubeosis iridis
Neovascularization in the iris that occurs in
various retinal disorders.
Etiology: causes - proliferativ diabetic
retinopathy
- retinal vein occlusion
- retinal periphlebitis
Signs and symptoms:
neovascularisation in the stroma
asymptomatic
neovascularisation in the angle of the
anterior chamber
irreversible
secondary angle closure glaucoma
Symptoms of the secondary angle
closure glaucoma:
loss of visual acuity
intense pain
conjunctival and ciliary
injection
“rock hard” eyeball
Differential diagnosis:
acute angle closure glaucoma
Treatment:
-prompt laser treatment of retinal
disorders
-transscleral freezing of the ciliar body
(cyclokryotherapy) to reduce intraocular
pressure (sec glaucoma)
-when falls, (or the eye shrinks(phtysis))
intense pain
enucleation is indicated
Prognosis: irreversible blindness
loss of an eye
Ciliar body
Structure: from the root of the iris to the ora
serrata
anterior - pars plicata
posterior- pars plana
ciliary processes
Function: ciliary muscle – accomodation
epithelium covering the ciliary
body – produces the aqueous
humor
Inflammation
1. Intermediate uveitis
Symptoms: decreased vision, floaters,
photopsia, rarely pain
Pathogenesis: immun-mediated or infectious,
inflammation of vitreous base
Risk factors: Inflammatory – MS, sarcoidosis
Infectious – Lyme, syphilis,
toxocariasis, tb
Genetics – assoc w/ HLA-DR 15
Ophthalmic picture:
pars planitis: idiopathic intermed.uveitis
associated with snowbank and vitreous
snowballs.
-inflammation involving the vitreous base
and peripheral retina
-anterior vitreous inflammation
-snowballs, snowbanks, peripheral venous
sheating
-CME
Prognosis:
-self-limited or chronic
-within first decade of life- more severe
inflammation and greater resistance to
therapy than in older pts.
Complications:
-permanent decreased visual acuity
-posterior subcapsular cataract
-cyclitic membrane
-CME
-epiretinal membrane
-retinal detachment
-hypotony
-retinal neovascularisation
-vitreous haemorrhage
-phtisis bulbi
Treatment:
-infectious- antibiotics
-periocular or systemic corticosteroids
-immunosuppressants (eg,cyclosporin,
azathioprine, mycophenolate mofetil,
methotrexate)
-vitrectomy – persistent vitreous debris or
haemorrhage (limiting visual function)
Choroid
Structure: middle tunic of the eyeball
bounded on the interior by
Bruch`s membrane
highly vascularised:
-vessel layer with large vessels
-capillary layer
highest blood flow in the entire body
Inflammation
1. Choroiditis:
Incidence: four cases per 100000 people
Symptoms: free of pain, blurred vision,
floaters
Etiology: toxoplasmosis
sarcoidosis
syphilis
Behcet`s disease
histoplasmosis
Ophthalmic picture:
-isolated or multiple choroiditis foci
-acute disease - ill defined white dots
-scarring – foci are sharply demarcated
with a yellowish-brown color
-major choroidal vessels are visible
-atrophic scars
-no cells in the vitreous bodyprimary choroidal process
-cellular infiltration of the vitreous bodyretinochoroiditis
Differential diagnosis:
retinal inflammations with vitritis
- caused by viruses or
Toxoplasma gondii
Treatment: antibiotics
steroids
Prognosis: inflammatory foci will heal within two
to six weeks
localised scotomas
chorioretinal scars
reduced visual acuity
Sympathetic ophthalmia
Perforating wound to the eye,
or intraocular surgery
Chronic irritation of one eye
Transferred uveitis in the fellow eye
Specific bilateral inflammation of the uveal
tract
Epidemiology: very rare
Etiology: occur in an unaffected eye even
years after penetrating injuries or
intraocular surgery in the fellow eye.
Tissues in the injured eye act as antigens
Autoimmune disorder in the unaffected eye
Symptoms: -limited range of accomodation
-photophobia
-diminished visual acuity
-pain
Ophthalmic picture:
-combined injections
-cells and protein in the anterior
chamber and vitreous body
-papillary and retinal edema
-granulomatosus inflammation
of the choroid
Differential diagnosis: -iridocyclitis
-choroiditis
Treatment:- the injured, usually blind eye
- must be enucleated to eliminate
the antigen
- high dose topical and systemic
steroid therapy
- concurrent immunosuppressives
(cyclophosphamide,
azatioprin)
Complications: -chronic clinical course
-severe complications
-secondary glaucoma
-secondary cataract
-retinal detachment
-shrinkage of the eyeball
-blindness
Tumors
1. Benign choroidal tumors
choroidal nevi: 11% of the population
secondary neovascularisation with retinal
edema
(usually asymptomatic)
2. Malignant tumors
Uveal melanoma - incidence of one per ten
thousand
- usually choroidal
- unilateral
Iris melanomas: often initially asymptomatic
melanoma cells in the
angle of the anterior chamber
Complications: secondary glaucoma
Therapy: segmental iridectomy
Ciliary body melanomas:
changes in accomodation and
refraction
Therapy: resected en bloc
Choroidal melanomas:
Symptomatic: - involvement of the macula reduces visual acuity
- retinal detachment
Diagnosis: transillumination, ultrasound,
fluorescein angiography
Therapy: radioactive isotopes (brachyterapy)
enucleation (>8mm x 5 mm)
Uveal metastases:
from: breast
lung
flat with little pigmentation