Disease entities Flashcards
anaemia pre-op
Microcytic anaemia
Iron deficiency anaemia
Thalassaemia
Normocytic anaemia
Anaemia of chronic disease
Macrocytic anaemia
B12 deficiency
Folate deficiency
Alcohol
Hypothyroidism
Sideroblastic anaemia
Condition where iron is available but red
blood cells are unable to incorporate it into
haemoglobin
Sjorgen’s syndrome
Affects the lacrimal gland and accessory lacrimal apparatus (glands of Wolfring
and Krause) and salivary glands
Lymphocytic infiltrate affecting conjunctival, oral and lacrimal acinar glands and
loss of conjunctival goblet cells
Impaired secretion of saliva and tears: dry mouth and eyes
anti-Rho and anti-La antibodies
Associated with other connective tissue diseases such as RA
rheumatoid eye disease
T-cell and immune complex mediated vasculitis
Features
Necrotizing scleritis and scleromalacia perforans
Peripheral corneal ulceration
Corneal melt (due to MMP release)
Macular oedema
Posterior nodular scleritis (may mimic melanoma)
bechet’s disease
Systemic vasculitis
HLA-B51
Prevalent in east Asia and the Mediterranean
Onset in the second to fourth decades
Triad
Oral aphthous ulcers (98-99% of patients)
Genital ulcers (80-87%)
Ocular disease (70%): panuveitis with hypopyon most commonly
An aggressive, sudden onset panuveitis
Non-granulomatous, necrotizing, obliterative vasculitis which can cause
posterior segment complications: BRVO, CMO, vitritis, neovascularisation
sympathetic ophthalmia
Bilateral granulomatous inflammation of the uvea (panuveitis) following injury to
one eye typically involving uveal incarceration in the sclera
Sensitisation of ocular antigens leads to uveitis mediated by MHC-class II CD4 T
cells
Uvea is thickened by infiltrate of macrophages
Small granulomas accumulate in the RPE: Dalen-Fuchs nodules (small discrete
yellowish infiltrates in the RPE)
giant cell arteritis
Affects cerebral arteries, ophthalmic arteris, posterior ciliary arteries and central retinal arteries
Local dendritic cells recruit and activate CD4 T cells
These direct the activity of activated macrophages, giant cells, smooth muscle cells
(vascular remodelling)
Inflammatory infiltrate
Macrophages and multinucleated giant cells
Lymphocytes
Plasma cells
Giant cells are typically near the fragmented internal elastic lamina
Fibrin thrombus obstructs vessel lumen
NB: retinal arterioles are NOT affected as they do not possess an elastic
layer. The CRA, ophthalmic artery and cerebral arteries may be affected
No antibodies have been detected in GCA
granulomatosis with polyangitis (wegener’s)
Granulomatous inflammation and necrosis
Ocular manifestations: scleritis, corneoscleral ulceration and orbital mass
c-ANCA (antineutrophil, anticytoplasmic antibody) positive in >90% of patients
with generalised Wegener’s
acute retinal necrosis
Viral aetiology: most commonly VZV, but also HSV. Rarely CMV and EBV
perhaps
Immunocompetent patients (compare to CMV retinitis which typically affects the
immunocompromised)
Clinical phases
Acute herpetic
o Granulomatous uveitis
o episcleritis/scleritis
o Vitritis (often severe)
o Retinitis (typically peripheral, compared to the posterior pole retinitis seen
in CMV). Viral inclusion bodies can be seen on light microscopy
Late cicatricial
o Retinal tears and detachment
o PVR
Treatment: aciclovir or valaciclovir
progressive outer retinal necoriss
Part of a spectrum of herpetic retinopathies continuous with ARN
Rapidly progressive
Immunocompromised patients
Again, typically caused by VZV, or HSV
Key feature: minimal intraocular inflammation
Typically no AC reaction or vitritis
Large, well-defined patches of white retinal opacification consistent with deep
necrosis
Peripheral or central
Multifocal
Retinal vasculopathy: sheathing and occlusion
Late staining on FFA
Retinal detachment
vogt-koyangi-harada (VKH)
Bilateral granulomatous panuveitis
Young adults (second and fifth decades)
Predominance in heavily pigmented patients
Female predominance
HLA-DR1 and HLA-DR4
VKH - acute granulomatosis reaction
Uveal thickening
158
Lymphocytic infiltrate
Epithelioid collections
Dalen-Fuch’s nodules: granulomas between RPE and Bruch’s
Vogt-Koyanagi syndrome
Chronic severe anterior uveitis
Alopecia
Poliosis
Vitiligo
Harada’s disease
Harada’s disease
Bilateral exudative uveitis
CSF pleocytosis
VKH
Typically a viral illness prodrome leading to an acute uveitis stage
Serous retinal detachment
Systemic findings
Sensorineural deafness
Headache
Dermatological effects as above
sarcoidosis
Afro-caribbean patients affected more than whites
Sarcoid nodules: non-caseating epithelioid histiocytes, multinucleated giant cells,
asteroid bodies and Schaumann bodies
Second to fifth decades
Ocular involvement in 25%
Mutton-fat KPs
TM nodules
Vitreous opacities (string of pearls)
Multifocal chorioretinal lesions
Peri-phlebitis
Optic disc nodules
Bilateral
thyroid eye disease
Immune-mediated condition directed at orbital fibroblasts which have increased
insulin-like growth factor 1 receptors
TSH receptor antibodies (TRAbs) cross react with orbital fibroblast antigens
resulting in inflammatory activation
Anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin may also be detected
Hashimoto’s thyroiditis has a weaker association with eye disease
histopathological changes with thyroid eye disease
Extraocular muscle enlargement
Patchy infiltration of lymphocytes, monocytes, mast cells and fibroblasts
Fibroblasts produce mucopolysaccharides which attract water causing swelling
Tendon sparing inflammation
sight threatening complications of thyroid eye disease
Dysthyroid optic neuropathy
Corneal exposure (keratopathy)
compressive optic neuropathy
homocystinuria
Reduction in levels of cystathione beta-synthetase, affecting methionine (an amino
acid)
Autosomal recessive
Features
Thromboembolic risk
Lens dislocation: metabolic abnormality of the zonules with a thick band of
PAS-positive material of the surface of the ciliary processes and pars plana
cystinosis
Abnormal membrane transport of cystine
Ocular manifestations
Cystine crystals in the cornea, retina, choroid, RPE, retina, conjunctiva
Bi-refringent crystals
aging and degeneration - hyalinisation
replacement of normal cells by an acellular,
collagenous/glycoprotein matrix
aging and degeneration - fatty changes
: eg. arcus senilis. Plasma lipids leak from blood vessels and are deposited in
the corneal stroma. Xanthelasma are a feature of macrophages containing lipids
collecting in the eyelid dermis
aging and degeneration - elastic fibre degeneration
associated with sun exposure. Pinguecula and
pterygium represent elastic material deposition within the conjunctiva leading to
bulbar nodules (pinguecula) and at the limbus (pterygium) which can encroach on
the cornea
aging and degeneration - pterygium
most common within the interpalpebral fissure
o Basophils predominate
o Absent cystic spaces
o Stromal elastosis
o Fibroblastic proliferation
o Stocker’s line: a line of iron at the advancing edge
o Conjunctival autografts and topical MMC can be used
aging and degeneration - macular degeneration
the scarring in disciform macular degeneration is a result of
fibrous metaplasia of RPE cells leading to collagen deposition. This follows
choroidal neovascular leakage and haemorrhage
Associated with polymorphisms in the complement factor H gene
The age-related eye disease study (AREDS) found that zinc, beta-carotene,
vitamins C and E reduced the progression of AMD
Latterly, lutein, zeaxanthin, B vitamins and omega-3 were found to also reduce
progression
age related changes
cornea: hassal-henlewarts, peripheral excrescnes of descements
ciliary epithelium hyperplasia
retina: periheral micoscytoiud degeneration
calcification
Metastatic calcification (occurs in hypercalcaemia)
Band keratopathy: calcium deposited in Bowman’s layer
o Managed with ETDA (ethylenediaminetetraacetic acid) which chelates
calcium
o Epithelium should be removed to expose calcium in Bowman’s layer
Dystrophic calcification (occurs in damaged or degenerating tissues)
Phthisis bulbi
amyloid
Insoluble fibrillar glycoprotein deposited around blood vessels and basement
membranes as an extracellular eosinophilic hyaline material
Stains pink (eosin) with H&E and is ‘apple’ green birefringent when examined
under polarized light with Congo red
types of amyloid
- Systemic - light chain derived OR serum AA protein derived
- localised
systemic amyloid
Associated with monoclonal plasma cell proliferation eg myeloma,
Waldenstrom’s macroglobulinaemia. Light-chain derived (AL)
Associated with chronic inflammation eg RA. acute-phase reactant derived
(serum AA protein)
Derived from polypeptide hormones in thyroid carcinoma
Derived from prealbumin in Alzheimer’s
Familial Mediterranean fever
localised amyloid
Deposition in endocrine tumours
Deposition in organs and joints of the elderly including in Alzheimers
Component of drusen in AMD
Deposited in the cornea in lattice dystrophy
occular associations with amyloid
Solitary nodule in eyelid, orbit, conjunctiva
Amyloid deposition in choroid and vitreous in systemic amyloidosis
Amyloid deposition in cornea
Characteristic of lattice dystrophy
pseudo-exfoliation syndrome
Age-related systemic disease
Granular eosinophilic material accumulates throughout the body
Contains elastin and fibrillin
Produced by abnormal basem
ent membranes of aging epithelial cells in trabeculum, lens capsule, iris and
ciliary body
White deposits on the lens, ciliary processes, iris surface and inner TM
Secondary open-angle glaucoma in 60% of patients (even if IOP is normal at
presentation)
Sampaolesi’s line on gonioscopy
Transillumination defects due to peripupillary atrophy
More common in females
Cataract surgery can be challenging due to poor dilation and zonular instability
pigment dispersion syndrome
More common in whites than blacks
Typically bilateral
Myopia increases the risk: concavity of the mid-peripheral iris (found in myopes
and long AL eyes) increases contact between the peripheral iris and zonules
leading to mechanical friction and pigment release
cotton wool spots
microinfarctions cause swollen axonal endings
hard exudate
underperfusion damages vascular endothelium leading to plasma
leakage into the outer plexiform layer. These exudates are eosinophilic masses
containing foamy macrophages
micro-aneurysms
pericyte necrosis secondary to ischaemia leads to weakening of
the capillary wall leading to bulges or blowouts. Gradually are filled by basement
membrane deposits and can disappear on FFA
flame haemorrhages
arteriole rupture with blood tracking the nerve fibre layer
dot haemorrhages
capillary rupture within the outer plexiform layer
blot haemorrhages
capillary bleeding between the photoreceptors and RPE
neovascularisation
grow from the venous side of the capillary bed in response to
ischaemia and leak on FFA. If the vitreous is detached they haemorrhage and form
traction bands. Vasoformative factors diffuse through the vitreous, PC and AC to
induce rubeosis iridis and neovascular glaucoma
diabetic retinopathy
Loss of pericytes (contractile cells that wrap around capillaries and are embedded
in the BM)
Thickening of the capillary basement membrane
Degeneration of capillary endothelial cells and breakdown of the inner bloodretinal barrier with leakage
Exudates
Microaneurysms
Inner nuclear and outer plexiform layers are initially affected and then oedema
spreads to create a cystoid appearance
Cotton wool spots: nerve fibre ischaemia
IRMA: irregular segmental growth and dilation of vessels from the venous end of
the circulation into areas of retinal ischaemia
Hyalinzation of vessels
coat’s disease
Not hereditary
Abnormality of arterial and venular endothelium
Leads to massive leakage of lipid-rich plasma into the retinal and subretinal space
Exudative retinal detachment
Vascular anomalies
Typically unilateral
Male predominance
cataract
Lens crystallins break down to albuminoids in response to aging and UV radiation
Tyrosine is released and converted to adrenaline and melanin
Lens pigmentation progresses from yellow to brown and then to black
secondary cataract
related to metabolic disturbance, radiation or trauma may
disrupt lens epithelial ionic transport mechanisms causing disorganisation or lens
proteins
conditions associated with keratoconus
retinitis pigmentosa
vernal keratoconjuncitivs
ROP
down’s syndrome and marfans
Cuases of leukocoria
causes of leukocoria is CREAM PIGMENT:
Cataract, Coats
Retinoblastoma, ROP
Endophthalmitis
Astrocytic hamartoma
Myelinated NFL
Persistent fetal vasculatur
Incontinentia pigmenti
Granuloma
Melanoma
FEVR (Familial EXUDATIVE vitreoretinopathy)
Norrie
Toxocariasis
Primary open angle glaucoma
Increases with age
Increased IOP leads to pressure-induced ischaemia due to occlusive disease of
the posterior ciliaries and direct mechanical pressure preventing axoplasmic
flow through the lamina cribrosa
The prelaminar nerve becomes atrophic but the macular and papillomacular
bundle are spared
The cup enlarges vertically more than horizontally
Genes associated with POAG
Myocilin gene (MYOC, formerly called TIGR) on chromosome 1 encodes
myocilin involved in the TM cell contractility
Optineurin (OPTN) gene on chromosome 10 is involved in exocytosis
secondary open angle glaucoma
angle obstruction by
Inflammatory cells
Haemorrhage
Tumour cells
Lens matter and macrophages (following degenerative rupture of the lens
capsule)
lens associated glaucoma
o Phacolytic glaucoma: open angle, pseudohypopyon
o Phacoanaphylactic: autoimmune granulomatous reaction following rupture
of the capsule
primary angle closure glaucoma
Also degenerative
Lens thickening leads to displacement of the pupillary part of the iris by the
anterior lens surface
This shallows the AC and pressure builds behind the iris
Iris bombe involved the peripheral iris pushing towards the TM
The acute pressure increase leads to blocked axoplasmic flow and papilloedema
secondary closed angle glaucoma
Anterior lens displacement by tumour
Anterior and posterior synechiae in uveitis
Rubeotic glaucoma: fibrovascular proliferation in the angle due to retinal
ischaemia
Malformation of the angle in congenital glaucoma
Phacomorphic
PAC suspect
occludable angle 180 degre
normal IOP and disc
PAC
ocludable angle +/- increase in IOP or PAS
normal optic nerve and no field damage
PACG
PAC with optic nerve damage and field loss