Eyedocs answers Flashcards
What are the side effects of 5-FU during glaucoma filtration surgery?
Ischaemic blebs
Hypotony
Suprachoroidal haemorrahge
What is the difference between lentigo maligna and melanoma?
both show proliferation of atypical spindle shaped melanocytes, but melanoma has dermal involvement, and lentigo only has involvement of the epidermis
What type of cell is in a Kaposi sarcoma? Which layer does it involve?
Proliferation of spindle shaped cells and vessels in the dermis layer
What stain is used to identify fungi? (5)
- Gomori-methamine silver - stains black
- Grocott hexamine silver - fungi + acanthomoeba stains black
- Periodic acid schiff - stains purple
- Calcufluor - stains white
- haematoxylin and eosin stains pink
What stain is used to identify calcium (2)
Alizarin Red
Von Kossa
What are the stains involved in dystrophies?
1) Reis-Bucklers
2) Granular Dystrophy
3) Macular dystrophy of cornea
1) Masson Trichome stains new collagen blue
2) Masson Trichome stains hyaline material red
3) Alician blue stains mucopolysaccharides
What are the differences in substance concentrations between aqueous humor and plasma? (3)
- AH has 15 x more ascorbate than plasma
- AH has 35 x less protein than plasma (0.2%)
- AH is more hypertonic and acidic than plasma
- What are granulomatous keratic precipitates made out of ?
- What are non-granulomatous KPs made out of
- Granulomatous KPs - macrophages
- Non-granulomatous KPs - lymphocytes and polymorphonuclear leukocytes
What are the effects of atropine - cholinergic antagonist (2 ocular, 3 systemic)
Ocular
1. mydriasis via iris sphincter muscle paralysis
2. cycloplegia via ciliary body paralysis
Systemic
3. Sedatory effect
4. Delays gastric emptying
5. Reduces sweating
What are the most frequent side effects for prostaglandin analogues? (7)
- Increased iris pigmentation
- Iris cyst formation
- Increased peri-ocular skin pigmentation
- Peri-orbital fat atrophy
- Eyelash hypertrichosis
- Iritis
- CMO
HLA Associations
1. Birdshot choroidoretinitis
2. Presumed Ocular histoplasmosis syndrome / MS
3. Sarcoidosis/Intermediate uveitis
4. Idiopathic ant uveitis, psoriatic, ank spond, Reiter’s, IBD
5. Retinal vasculitis
6. Behcet’s disease
7. Juvenile RA, VKH syndrome, sympathetic ophthalmia
- Birdshot - HLA-A29
- POHS - B7, DR2. MS - B7, DR2, DR15
- Sarcoidosis / IU - HLA-B8
- Idopathic AU, psoriatic, AS, Reiter’s, IBD - HLAB27
- Retinal vasculitis - B44
- Behcet’s - B51
- JRA, VKH, SO - DR4
- What are the main HIV medications?
- What are their main side effects?
- Ritonavir - nausea and diarrhoea
- Zidovudine - cytopaenia
- Zalcitabine - peripheral neuropathy
- Didanosine - pancreatitis
What is the flicker fusion threshold for rods vs cones?
Rods is 20Hz, Cones is 60Hz
Which immunoglobulin passes through the placenta to assist foetal immunity?
IgG
What is the main immunoglobulin in human tears?
IgA
Which sinuses drain into…
1. the superior meatus
2. middle meatus
3. inferior meatus
- superior - sphenoid and posterior ethmoid
- middle - maxillary, anterior ethmoid, frontal
- inferior - opening of nasolacrimal duct
What is the route of the cavernous sinus?
1. Extends from the …. to the ….
2. Opens posteriorly into the ….
3. What structures are on the lateral wall?
4. What structure runs medially?
5. What structure runs in between?
- Extends from SOF to apex of temporal bone
- Opens posteriorly into petrosal sinuses
- Lateral wall - CN 3, CN 4, CN V1, V2
- Medially - internal carotid artery
- In between - CN 6 (abducens)
What is the most appropriate treatment for peripheral CMV retinitis?
oral ganciclovir
Ribosomes are inhibited by which drug?
Chloramphenicol
inositol triphosphate is activated by what? what is its pathway?
activated by alpha one adrenoceptors. Binds to endoplasmic reticulum membrane, increases concentration of intracellular calcium –> smooth muscle contraction –> ++ exocrine secretion and force/rate of cardiac contractions
What is the optimal length for primers in PCR?
17-20 base pairs
What is the optimal temperature for DNA polymerase?
70 degrees
What is ciclosporin’s main side effect?
nephrotoxicity, does not cause bone marrow suppression
What is the difference between the acute inflammatory response and the acute immune response?
INFLAMMATORY:
- vascular phase (histamine, kinins and prostaglandins) causing increased vascular permeability followed by cellular phase (recruitment of macrophages and neutrophils
- it is adaptive and specific
IMMUNE:
- non-specific, non-adaptive and does not exhibit memory
What are the main differences between duction, version and vergence eye movements?
Duction: single uniocular eye movements (adduction, abduction etc)
Version: binocular eye movements - conjugate , synchronous and symmetric movements in same direction
Vergence: binocular eye movements - disconjugate movement of eyes in opposite directions
What are the main characteristics of vergence eye movement -
It is a tracking movement slower than pursuit movement.
It is voluntary and stimulated by blurred images on the retina
It is limited by near and far point of accommodation
Which immunoglobulin is the first antibody to appear in infection?
IgM
What pathway does IgA activate?
Activates the alternative complement pathway (unlike other antibodies that activate the classical pathway)
The posterior pigmented iris epithelium is a continuation of?
The anterior pigmented iris epithelium is a continuation of?
posterior - non-pigmented epithelium of ciliary body
anterior - pigmented epithelium of ciliary body
What is the zonuluae occludantes and where are they located?
- tight junctions between cells
- between RPE cells of retina (blood-retinal barrier) and between non-pigmented ciliary epithelium (blood aqueous barrier)
What receptors do macrophages have? (3)
- pattern recognition receptors which recognise microbial components
- surface receptors that recognise Fc portion of immunoglobulin and complement components. Binding of these receptors to their ligands enhances phagocytosis of antigen (opsonisation)
- MHC class II molecules on surface when activated - present antigen to helper T-cells. Secrete IL-12 which directs T-cell differentiation to Th1 subset.
What pro-inflammatory cytokines do macrophages produce?
IL-1, IL-6, and TNF