Lecture 4 & 5: Ocular Diseases Flashcards
1
Q
What are some features of the external eye?
A
- Lacrimal gland, duct, canal, sac etc
- Pupil
- Sclera
- Iris
- Eyelid
- Limbus
- Bulbar Conjunctiva
2
Q
What is the structure and function of the pupil?
A
- Black, circular opening which controls the amount of light entering eye
- Controlled by sphincter and dilator muscles
3
Q
What is miosis and mydriasis of the pupil?
A
- Miosis: Excessive constriction of the eye, M3 muscarinic (often seen in opioid toxicity)
- Mydriasis: Dilation (a1 adrenergic)
4
Q
What is the structure and function of the sclera?
A
- White outer layer
- For protection and structural support
5
Q
What is the structure of the iris?
A
- Coloured part of eye that surrounds pupil
6
Q
What is the structure of the limbus?
A
- Cornea/iris meets sclera
7
Q
What is the structure and function of the bulbar conjunctiva?
A
- Covers white part of eye
- Protects eye against dust/ bacteria
8
Q
How does the lacrimal drainage system work in the eye?
A
- Lacrimal gland secretes aqueous tears to lubricate and protect which pass through lacrimal gland ducts
- Corner of eye = lacrimal drainage system
- Lacrimal punta, canal, sac, duct, nose
9
Q
What are the features of the internal eye?
A
- Cornea
- Lens
- Ciliary muscles
- Anterior chamber
- Choroid
- Macula
- Optic Nerve
- Retina
10
Q
What is the structure and function of the Cornea?
A
- Front, outermost layer
- Transparent, curved
- Main refractive surface, focus light as it enters eye
11
Q
What is the structure and function of the lens?
A
- Behind pupil and iris
- Fine tunes and focuses for near or far vision
- Shape changes due to ciliary muscles
12
Q
What is the structure and function of ciliary muscles?
A
- Smooth muscle which control shape of lens to help focus
- Ciliary body produces aqueous humour to keep eye lubricated.
13
Q
What is the anterior chamber?
A
- Space between cornea and iris
- Clear fluid (aqueous humour) that lubricates eye
- Maintains intraocular pressure as the humour drains between anterior and posterior chamber and back by capillary meshwork
14
Q
What is the structure and function of choroid?
A
- Vascular layer between sclera and retina
- Blood supply to retina
15
Q
What is the structure and function of Macula?
A
- Small yellowish area, in the central part of retina
- Fovea is the central part of macula
- For sharp central vision
16
Q
What does the Optic Nerve do?
A
- Crainial nerve 2 - transmits signals to brain
17
Q
What does the retina do?
A
- Thin membrane with specialised cells (photoceptors)
- Convert light into neural signals for brain processing
18
Q
What are the 2 different photoreceptors found in the retina?
A
- Rods: Sensitive to light (120 mill rods)
- Cones: Sensitive to colours. Concentrated in macula
19
Q
What are the 5 eye conditions that cause 80% of vision impairment in over 40s?
A
- Age-related macular degeneration
- Cataract
- Diabetic Retinopathy
- Glaucoma
- Under-corrected/ uncorrected refractive error
20
Q
What is age-related macular degeneration and what are some functional implications?
A
- Chronic degenerative condition that affects the central vision (macula), not enough blood supply to area
- Difficulty distinguishing faces, reading, straight lines = distorted
21
Q
What is a cataract?
A
- Clouding of the lens inside eye
- Light is scattered as it enters the eye, causing blurred vision, reduced contrast, double vision around lights
22
Q
What can increase the risk of a cataract and what is used to solve it?
A
- Long term corticosteroid
- UV
- Aging
- Smoking
- Diabetes
23
Q
What is diabetic Retinopathy?
A
- Complication of diabetes
- Affects small blood vessels of retina.
- Epithelial cells of BV are thin and more prone to damage
- BV leak and bleed inside eye
24
Q
What are the functional implications of diabetic retinopathy?
A
- Difficulty w/ fine details
- Fluctuations in vision from hour-hour
- Hazy/double vision
- Sensitive to light & difficulty seeing in low light
- Appearance of clouds moving in vision obstructing sight
25
What are the 4 stages of diabetic retinopathy and which ones do you treat?
- Mild non-proliferative
- Moderate non-proliferative
- Severe non-proliferative
- Proliferative: Treat w/ surgery. Scatter laser treatment to shrink abnormal blood vessels
- Others = no treatment unless macular oedema and treat w/ focal laser treatment
26
What is Glaucoma?
- Increased intraocular pressure due to malfunction in aqueous humour drainage system by trabecular mesh work and causes optic nerve damage
- Relieving pressure on nerve reduces progression
- Gradual loss of peripheral vision
- Untreated = complete vision loss
- Family = x8 more likely
27
What are the functional implications of Glaucoma?
- No implications in early disease
- Difficulty adjusting to light changes, tripping, increased sensitivity
-
28
What are some risk factors for Glaucoma?
- Extreme refractive error
- Diabetes
- Migraines
- Previous eye injury
- Sleep apnoea
- Males
- Corticosteroids
29
What are the differences with open and closed glaucoma?
- Cause: Open = slow blockage of Trabecular meshwork, Closed = Sudden blockage due to narrow angle
- Onset: Open = gradual, chronic, Closed = sudden, acute
- Symptoms: Open = Painless, gradual vision loss, closed = severe eye pain, redness, sudden vision loss
- Emergency: Open = no but needs treatment, closed = yes urgent
30
Which type of people are more prevalent for Glaucoma and need eye tests?
- Over 40
- Genetic link
- Screen w/ diabetes
- Over 40 w/ first degree relatives with Glaucoma = free test
31
What is the treatment of Glaucoma?
- Parasymapthomimetic (pilocarpine)
- Sympathomimetic (brimonidine)
- Beta blocker drops (timolol)
- Prostaglandin analogues and Prostamides
- Carbonic anyhydrase inhibitors: Dorzolamide, Brinzplamide
32
What is refractive error?
- Focusing disorder and most common vision impairment w/ genetic link
- When eye doesnt properly refract (bend) light causing blurred vision
33
What are the different types of refractive error?
- Hyperopia (far sighted): only see far objects. Object focuses behind retina
- Myopia (near sighted): only see close objects. Object focuses in front of retina
- Astigmatism: Abnormal shaped cornea (egg shape instead of spherical) light focused unevenly at all distances
- Presbyopia: Rigidity of lens (old age), unable to focus on close objects (over 40)
34
What are the functional complications of refractive error?
- Hyperopia: Cant see near
- Myopia: Cant see far
- Astigmatism: Blurred vision
- Presbyopia: (age focus difficulty) cant see near objects
35
What are the 2 types of contact lens?
- Rapid gas permeable
- Soft contact lens
36
What are rapid gas permeable lens?
- Smaller than soft and rest within corneal area
- Longer to get used to, more durable
- Replaced every 6-12 months and better w/ irregular shaped eyes
- Sharper vision
37
What are soft contact lens?
- Like thick cling film, larger and cover cornea so lens can be seen on sclera
- Can replace daily, monthly and more comfortable
- Incorporate water to prevent drying out
- More dangerous to use w/ eye drops
38
What are some contact care advice for soft contact lens?
- Daily cleaning using surfactant to remove microns, lipids, dirt, makeup
- Weekly protein removal to remove tear proteins
- Saline solution used for rinsing
39
What are some contact lens care advice for rapid gas per
- Clean lens after wearing using a lens solution to rinse and remove debris and protein build up. Never tap water
- Use wetting solution to keep lens hydrated and reduce friction and deposits
40
What are some common contact lens problems?
- Inappropriate fit
- Aged contact lens - over wearing beyond time
- Poor hygiene - not washing hands, using tap water
- Sleeping in them
41
What are rules when using OTC products w/ contact lens
- Can be used w/ RGP
- Soft lens can absorb components of eye drops. Leave lens out of eye for 15 mins after application. Chlorhexidine drops can be used as an antimicrobial
42
What are the effects of some diseases and meds on contact lens?
- Lens dicolouration: from nitrofurantoin, rifampicin, sulfalazine and tetracyclines
- Hormonal changes causes dry eyes and blurred vision
- Cold sores or infections: advised not to wear
43
What are some eye conditions/ effects that someone can come into community pharmacy with and needs referral?
- Babies under 2 who need chloramphenicol
- Babies w/ sticky eyes from birth
- Patient undergone opthalmic/laser eye surgery
- Chloramphenicol: personal/ family HX w/ bone marrow problems
- Recurring problems and any due to trauma of eye
- If after OTC, condition fails to resolve after few days
- Drug induced eye problems
44
What are the 5 Ps that need referral when seen in patient's eye?
- Pain
- Photosensitivity
- Pus w/other symptoms
- Pupils (change)
- Problems w/ vision
45
What are some common eye conditions treated in pharmacy?
- Red eye
- Disorders of eyelid
- Bacterial conjunctivitis
- Tear disorders
46
What are examples of eye conditions that affect the conjunctiva?
- Conjunctivitis
- Subconjunctival Haemorrhage
- Inflamed eyes
47
What are the causes of conjunctivitis?
- Viral
- Bacterial (chlamydial)
- Allergic
48
What is viral conjunctivitis?
- Red, itchy, watery eye
- Can affect 1/ both eyes
- Contagious
- Takes longer to resolve
49
What medicine can you give OTC to treat conjunctivitis and what are some counselling points?
- Chloramphenicol eye drops
- P med
- 1 drop each eye every 2hrs for 2 days then every 4hrs after or ointment
- Leave in fridge
- 5 day course, discard after
- Dont share bottles
- Side effects: stinging, burning, blurring vision
50
What is allergic conjunctivitis?
- Very similar in appearance to viral conjunctivitis
- Accompanied w/ nasal congestion, sneezing, eyelid swelling and sensitivity to light
51
How do you treat allergic conjunctivitis?
- Avoid exposure to trigger
- Oral antihistamines
- Cold compress
- Antihistaminic eye drops (short term)
- Sodium cromoglicate for long term
- Steroid long term can cause cataract/severe infection
51
What is Subconjunctival haemmorhage?
- Small vessel burst (blood in eye)
- Harmless and resolves spontaneously (7-14 days)
- Refer is recurring or on warfarin
52
What are inflamed eyes and how to treat?
- Tired/ irritated
- Over exposure to smoke, dust, rubbing
- Eye lotions or drops with astringents or lubricants to soothe
- Refer if persistent
53
What are some disorders of the eyelid?
- Styes (Hordeolum)
- Chalzion
- Marginal Blepharitis
- Entropion
- Ectropion
54
What is a Stye?
- Acute localised ebscess usually caused by staphylococcal infection (pus filled)
- Inflammation of hair follicle of eyelid
- Resolves spontaneously (apply hot compress to closed lid for mins, cotton pads in circular movements to drain)
- If not resolved in 7 days = refer
55
What is a Chalzion
- Cyst of meibomian gland that secretes fluid to stop sticky eyes
- Spontaneously resolves but needs few weeks. Treat same as styes
56
What is Marginal Blepharitis?
- Inflammation of the margin of the eyelid
- Chronic condition: Symptoms improved and not cured
- Compliance to treatment and lid hygiene = important
- Sight rarely affected
57
What is Entropion and Ectropion?
- Entropion: Inversion of eyelid in eye
- Ectropion: Upturned eyelids
58
What are some tips for eyelid hygiene?
- Warm compress on lids and margins to loosen crusts
- Massage eyelids. gently roll first finger to push oil and fluid out
- Cleanse lids 2 x a week then once improved do once
- If not resolve in 7 days = GP
- Bacterial blepharitis use antibacterial ointment on lashes BD/TDS for 7 days not chloramphenicol or oral antibiotics
59
What are the 2 tear disorders?
- Watering eyes
- Dry eyes
60
What is watering eyes?
- Excessive lacrimation w/ no other symptoms
- Associated w/ interrupted drainage of tear film due to blockage of nasolacrimal gland
- Infants can develop. Spontaneous heal. massage lacrimal sac
- Can be a symptom of dry eyes due to inflammation process
- Can be due to ectropion or entropion esp in older people
61
What are dry eyes? Who is more susceptible and how to treat?
- Contact lens wearers = susceptible
- Life long
- Dry eye w/ infection is temp
- Refer w/ dry eye to eliminate corneal ulceration
- Treat: lubrication (artificial tears)
- 2 types: eye drops w/ preservatives (eye irritation) and preservative free = single use
62
What are some drugs that can induce eye problems?
- Beta blockers, isotretinoin (cause dry eyes)
- Anticholinergics: Blurry vision and dry eyes
- Corticosteroids: Cataract, glaucoma
- Hydroxychloroquine: irreversible vision loss
63
What are some systemic diseases causing eye conditions?
- Eczema
- Diabetes
- HTN
- Hyperthroidism
- IBD
- Migraine
- STI
64
What are some tips to keep eyes healthy?
- Adherence to eye drops when needed. Common problems: difficulty aiming bottle, shaky hands
- Lower lid, pull down gently, drop instilled into corner of conjunctival sac and look down
- Wash and dry hands before administration
- Can use eye drop dispensers: Opticare Universal
65
What is the frequency of eye exams for:
- Over 40/ fhx of glaucoma or ocular hypertension
- Diabetes
- Under 40 w/ no risk factors (medical/ocular condition)
- Upto 16 w/ binocular vision anomaly (eyes dont work together properly or corrected refractive error)
- 1yr
- 1yr
- 2/3 yrs
- 6 months
