Paeds Flashcards
Name the longest to shortest rectii muscle?
SR, MR, LR, IR
Whats the largest rectus muscle?
MR
Which rectus muscle has the longest and shortest tendon lengths?
Longest - LR
Shortest - MR
Where is the origin of the four extraocular rectus muscles
Annulus of Zinn. Tendinous ring (thickened periosteum) at the apex of the orbital cavity.
Blood Supply of
A) Superior rectus B) Inferior rectus C) Medial rectus D) Lateral rectus E) Superior oblique F) Inferior oblique
A - Superior muscular branch of ophthalmic art, 2 anterior ciliary art.
B- Inferior muscular branch of ophthalmic art, Infraorbital art, 2 ant. ciliary art
C - Inferior muscular branch of ophthalmic art, 2 ant. ciliary art
D - Lacrimal artery
E - Superior muscular branch of ophthalmic art
F -Inferior muscular branch of ophthalmic art, Infraorbital art
Movements of Eyes A) Superior rectus B) Inferior rectus C) Medial rectus D) Lateral rectus E) Superior oblique F) Inferior oblique
A) Elevation, Intorsion (Inward/Medial Rotation), Adduction
B) Depression, Extorsion, Adduction
C) Adduction
D) Abduction
E) Depression, Intorsion, Abduction
F) Elevation, Extortion (Outward/Lateral Rotation), Abduction
Explain Eye movements
- Primary
- Secondary
- Tertiary
- Looking straight ahead
- Eye is directed (U, D, L, R)
- Eye is directed in oblique positions
Retinoblastoma is caused by the loss of function of which gene and where?
Loss of function of the Rb tumour suppressor gene on C13q14
2 separate mutations - Sporadically (Cell body loses Rb gene + Another mutation of cell body) 90%
Genetically - 2 Cell bodies missing Rb gene + mutation happens.
Leukocoria, Macroscopically seen as a white mass, Metastatic dissemination of retinoblastoma is via the blood stream
Define Leukocoria?
Normal white pupillary reflex. (White pupil)
Retinoblastoma Cataracts Retinal detachment Retinopathy of prematurity Coats disease Retinal Astrocytic hamartoma Persistent fetal vasculature
What is the most common benign periorbital tumours of infants?
What visual issue can they cause?
Capillary Haemangioma
Possible ptosis, Reduced VA (due to amblyopia), Astigmatism
What syndrome is linked with Port wine stain affecting the face and eyes?
What visual issue can it cause?
Sturge weber ( Overabundance of capillaries near the surface of the skin. Blood vessels on the same side of the brain as the stain)
Choroidal haemangioma
Glaucoma
Seizures,
Describe ROP
Pathology, Treatment
Disorganised and excessive growth of retinal blood vessels in premature infants EXPOSED TO HIGH O2 concentrations.
When oxygen is removed - blood vessels start growing rapidly into the vitreous of the eye.
Tx: Laser photocoagulation from those presenting at Stage 3+ disease
3 - Extra retinal detachment
4 - Partial
5 - Total Retinal detachment
Who is at risk of ROP?
Premature babies <31W or Low birth weight <1.5kg
Define Coats disease?
Abnormal development of retinal blood vessels and retinal hard exudates.
Characteristic presentation - Xanthocoria (due to hard exudates)
Complications - RD (Hard exudates thicken the retina)
Tx: Manage hard retinal exudation, anti-VEGF through retinal laser, If RD consider scleral buckling
What signs do you get with optic nerve dysfunction?
Reduced colour vision, VA, RAPD
Tell me what ages visual acuity is tested for:
A) Cardiff Cards
B) Kay pictures
C) Sheridan-gardiner
D) Keeler LogMar or Snellen Chart
A - 6M to 2 yrs
B - 2yrs to 3yrs
C- 3yrs to 5yrs
D - Over 4 Years of age.
Snellen for literate children and adults.
Keeler LM for illiterate adults/pre-school children
Differentials for Leukocoria?
PREDICT
Persistant hyperlastic primary vitreous Retinoblastoma / ROP / RD Endophthalmitis Dysplasia of retina Inflammatory cyclitic membrane Congenital cataract/ Coat's disease Toxocaiasis
Flexner-Wintersteiner Rosettes
Histological finiding in which condition?
Retinoblastoma
What is amblyopia?
Unilateral decrease in VA caused by vision deprivation/abnormal binocular interaction. Defect in central visual processing.
“Loss of the ability to see clearly through one eye”
3 Treatments for Amblyopia
Occlusion therapy - Patching of better eye <8
Penalisation - Using atropine to reduce VA of better eye
Medically - Dopamine (As an adjunct)
3 Treatments for Amblyopia
Occlusion therapy - Patching of better eye <8
Penalisation - Using atropine to reduce VA of better eye (Blurs the eye via relaxation of muscles, dilation)
Medically - Dopamine (As an adjunct) - Increases contrast sensitivity in amblyopic eye only (dopaminergic neurons influence visual cortical plasticity)
What are the types of Amblyopia?
1 - Starbismic 2 - Anisometropic 3 - Stimulus deprivation 4 - Ametropic 5 - Astigmatic
Explain a Congenital nasolacrimal system obstruction?
Define?
Treatment?
A relatively common condition causing excessive tearing or mucoid discharge from the eyes.
Usually affects <1Y , Blockage of the lacrimal drainage system (valve of Hasner/Tear ducts)
The membranous valve of Hasner opens spontaneously or with gentle massage of the nasolacrimal sac within the first 6 to 12 months of life.
> 12 months, the chances of spontaneously opening are less and nasolacrimal probing is indicated. Should multiple probings fail, silicon tube intubation can be tried/ DCR (dacryocystorhinostomy) surgery
What is the main reason for pseudo-esotropia?
Epicanthal folds in infants.
These recede as the face matures.
Corneal light reflex is symmetrical in both eyes. [Asymmetry = True squint]
What conditions are associated with cataracts in juveniles and young adults?
NF Type 2
Myotonic dystrophy
Atopic dermatitis
Define
A - Yoke muscles
B - Synergists muscles
C - Agonist-antagonists muscles
A - Yoke muscles are pairs of muscles in different eyes which produce conjugate, directional gaze. (Gaze in the same direction)
B - Synergists are pairs of muscles in the same eye which move the eye in the same direction.
C - Agonist-antagonists are pairs of muscles in the same eye that move the eye in opposite directions
Chromosomes affected for the following genetic conditions?
A - Retinoblastoma B- Stargardt's C- Myotonic dystrophy D- Granular, Avellino, Reis-Buckler, and Lattice I dystrophies E- Marfans F- aniridia G -Alagille syndrome H- Behcet's disease I - Birdshot chorioretinopathy
A- 13q14 B- 1p C- 19 D -5q E -15 F -11p G -20 H - HLAB51 I -HLA A29
Left Eye is EXOTROPIC what will happen to right eye when the L.Eye is covered?
The right eye fixates, so the R. eye will NOT move when the left eye is covered. The image on the right will disappear
Exotropia - Causes crossed diplopia (right image comes from left eye and vice versa)
Esotropia causes uncrossed diplopia (right image comes from right eye, etc)
