BCS Flashcards
Drugs that cause issues with hearing - most common?
Gentamicin (and other with aminoglycosides), antidepressents, high dose NSAIDs, others
What is considered normal volume?
60dB
Myopia
nearsightedness, can’t see things that are far away
Hypermetropia
Longsightedness, can’t see things that are close up
Astigmatism
Astigmatism is a type of refractive error caused by the irregularities in the shape of a person’s cornea. In this condition, the eye fails to focus the light equally on the retina leading to blurred or distorted vision. It can be present at the time of birth, or can develop gradually in life.
REVIEW - What does ophthalmology look at?
Eyes, structures around the eyes, vision, eye movements
What is the role of the cornea?
It is the major refractive surface of the eye Goal is for light to meet at a point on the back Snell’s law - when light moves between surfaces of different density, the rays bend
What are the layers of tear film?
On top of cornea, air to tear journey bends the light

What is the role of the lens? Near or far?

Describe the defects that make people near or farsighted? What are the proper names for these conditions? What kind of lenses do they require?
Near - myopic
Far - hypermetropic

Define presbyopia
long-sightedness caused by loss of elasticity of the lens of the eye, occurring typically in middle and old age.
Weakening of accommodation
How is the pupi innervated? What controls constriction? dilation?
Sym - dilates the pupil (arousal / fear, need wider vision), starts in hypothalamus and has long journey
Para - constricts to focus (like for reading), runs along 3rd cranial nerve

Describe the pupil light reflex
If you shine light in one eye, both will constrict

Describe th pupil near reflex
If you hold something near the nose, pupils get small (miosis), accommodate (flattening of lens) and converge (look towards nose)
Why are pupils clinically important?
- Window into the pre-chiasmal afferent visual pathway (retina and optic nerve)
- Window into the III nerve function
REVIEW overview on pupils
- •Two separate innervation: symp and parasymp
- •Symp goes via down the spinal cord, then up the neck, internal CA
- •Symp dilates pupil – fear and arousal
- •Parasymp travels from the midbrain with III
- •Parasymp for light reflex and near reflex
- •Pupil reflex tested as part of neuro exam
What is the aqueous humour? Where is it produced? What path does it follow? What does it do (3)? What issue can it cause?
- Produced by: ciliary body
- Fills the anterior chamber of the eye and hydrates the vitreous
- Supplies oxygen and nutrients to the posterior cornea
- Maintains intra-ocular pressure and therefore eyeball shape
- ISSUE: Disorders of drainage cause glaucoma
PATH: •Drains through angle structures (trabecular meshwork, canal of Schlemm)

What is glaucoma? What are the key diagnostic signs? (3) Patient usually presents with what symptoms? What is the main risk factor?
- Disease of the optic nerve/retinal ganglion cells
- Potentially blinding
- Symptoms: generally none
- 3 key signs:
- Raised intra-ocular pressure
- Optic disc cupping
- Visual field loss
- Main risk factor is AGE
What is normal intraocular pressure? How high can it be in glaucoma?
10-21mmHg
In glaucoma can be 25, 30, 35…
Potential treatments for glaucoma
- •Medication (drops)
- Reduce aqueous production (B blockers)
- Increase outflow (prostaglandin analogues)
- Surgery
- trabeculectomy
What is the most common eye disease worldwide? What is the top eye disease in UK?
Cataracts worldwide
In UK< age-related macular degeneration
What is cataracts? WHat are the risk factors? Symptoms? Signs? Treatment
- •Loss of clarity of the lens
- •Risk factors: age, smoking, diabetes, steroids, Few congenital
- •Symptoms: blurring, glare, monoc double vision
- •Signs: reduced acuity, normal fields, normal pupils, dim red reflex, hazy view of fundus
Treatment: suck out lens and put in synthetic
What is the neurotransmittor associated with parkinson’s disease?
A drop in dopamine
What is the neurotransmittor associated with psychosis and schizophrenia?
Increase in dopamine






