Ophthalmology Flashcards
What is Cataracts
Opacification of the lens of the eye
What are causes of Cataracts
Most are idiopathic
Secondary
Local: Trauma, uveitis
Systemic: DM, Wilson’s disease, Scleroderma, Steroids
Congenital: Congenital rubella syndrome
Major cause of treatable blindness worldwide
What are the signs and symptoms of Cataracts
- Gradual-onset painless loss of vision
- Glare from bright light - Loss of red reflex
Some
- Vision may worsen in bright light
- Monoocular diplopia with haloes around lights
- Begin to read without glasses
Hazy lens appearance
Reduced visual acuity
How is Cataracts diagnosed
Glare vision test - Reduced visual acuity
Slit lamp examination of the anterior chamber - Cataract visible
What is Conjunctivitis
Inflammation of the conjunctiva
Associated inflammation of the cornea = Keratoconjunctivitis
Associated eyelid involvement = Blepharoconjunctivitis
What are causes of Conjunctivitis
Infectious
Viral - Adenovirus, HSV, EBV, VZV
Bacterial - Pneumoccocus, Staph aureus, Moraxella catarrhalis and Haemophilus influenzae
Non-infectious Allergic Mechanical/irritative/toxic Immune-mediated Neoplastic
What are the signs and symptoms of Conjunctivitis
- Red eye
- Irritation, discomfort and grittiness
- Discharge (may be watery, mucoid, sticky or purulent depending on cause)
- Photophobia (suggest corneal involvement)
- Visual acuity usually unaltered
- Conjunctival injection (Blood shot eyes)
- Dilated conjunctival vessels
- Conjunctival chemosis (swell of the conjunctiva)
- Conjunctival follicles (round collections of lymphocytes appearing as small dome-shaped nodules)
- Conjunctival papillae (associated with allergic immune response)
How is Conjunctival diagnosed
Clinical diagnosis
Causative: Rapid adenovirus immunoassay Cell culture Gram stain PCR Ocular pH
What is Glaucoma
This is optic neuropathy with typical field defects associated with ocular HTN (IOP >21mmHg)
What are the different types of Glaucoma
- Acute closed-angle Glaucoma (ACAG)
- Chronic closed-angle Glaucoma
- Primary open-angle Glaucoma (POAG)
What are the causes of Glaucoma
Trauma
Uveitis
Steroids
Rebeosis iridis - Formation of new blood vessel on the surface of the iris
Congenital: Buphthalmos (enlargement of the eye balls)
3rd most common cause of blindness worldwide
What are the symptoms of Glaucoma
ACAG
- Painful red eye
- Vomiting
- Impaired vision
- Haloes seen around lights
POAG
- Usually ASYMPTOMATIC
- Peripheral visual field loss
Congenital
- Buphthalmos
- Watering
- Cloudy cornea
What are the signs of Glaucoma
ACAG
- Red eye
- Hazy cornea
- Loss of red reflex
- Fixed and dilated pupil
- Eye is tender and hard on palpation
- Cupped optic disc
- Visual field defect
- Moderated raised IOP
POAG
- Optic disc cupped
- Increase IOP
- Scotomas
- Notching of optic nerve cup
- Loss of nerve fibre layer
How is Glaucoma diagnosed][
Goldmann Applanation Tonometry - Standard method of measuring IOP = Normal Is 15mmHg
Pachymetry
US or optical snaking to measure central corneal thickness (CCT) <590mm = Higher risk of glaucoma
Fundoscopy
Detects pathologically cupped optic disc
Gonioscopy - Assess iridocorneal angle
Perimetry (Visual field testing)
What is Uveitis
This is inflammation of the iris and ciliary body
What are the causes of Uveitis
May be caused by infection (HSV)
Manifestation of systemic inflammatory conditions - Reactive arthritis, AS, IBD, Sarcoidosis, Behcet’s disease
Symphathetic ophthalmia - Inflammation of the contralateral eye weeks/months after penetrating injury. Recognition of eye antigens in the contralateral eye by T-cells that were activated by the initial presenting injury to the opposite eye
What are the signs and symptoms of Uveitis
Pain due to inflammation Pain during accommodation Photophobia Red eyes Blurred vision Lacrimation
Ciliary flush
Hypopyon - Exudate and inflammatory cells in the inferior angle of the anterior chamber
Small irregular pupil due to adhesions of the iris to the lens
Slit lamp - Keratic precipitates (Leukocytes deposits on the corneal endothelium)
Fundoscopy - Exclude retinal detachment
Signs of complications (Increased IOP, Cataract)
How is Uveitis diagnosed
Clinical diagnosis
Investigations for associated conditions
