Eyedocs Notes Flashcards
What is the term for the type of nystagmus that is absent when both eyes are open?
LATENT
Latent nystagmus is only detectable under certain conditions, such as when one eye is occluded or blurred.
Fast phase to fixing eye, null point in adduction, face turn towards fixing eye
Define MANIFEST nystagmus.
Present with both eyes open but increases if stimulus is reduced to one eye
It may also be jerk-type and is associated with conditions like congenital esotropia.
What is the definition of the horopter?
The horopter is the spatial plane where objects appear to be in single vision.
In front and behind the horopter we find Panum fusional space, where objects are seen with stereopsis - non-corresponding retinal points are stimulated
How many degrees of spatial vision does Panum fusional space provide?
6’ arc in the centre and 30-40’ arc in the periphery
This space is located in front and behind the horopter and stimulates slightly non-corresponding retinal points.
What is the sensory innervation source for the lacrimal gland?
Lacrimal nerve (branch of ophthalmic nerve V1)
The sensory fibers travel via the greater petrosal nerve.
What is the parasympathetic innervation pathway for the lacrimal gland?
Superior salivatory nucleus VII nerve via greater petrodollar nerve → pterygopalatine ganglion → zygomatic nerves (branches of maxillary nerve V2)
This pathway is essential for tear production.
What are OWL-eye inclusion bodies associated with?
CMV (Cytomegalovirus) infection
These are characteristic findings in certain viral infections affecting the eye.
What is the procedure of choice for of eyelid defects up to 30%?
Direct closure +/- cantholysis
How to repair eyelid defects up to 70%?
Tenzel semicircularflap
This technique is used in reconstructive eyelid surgery.
What percentage indicates a Hughes flap procedure?
> 70%
This is a surgical technique used for eyelid reconstruction when a significant defect is present. Cutler-beard flap and Frickle flap are other options for significant defects.
Characteristics of Idiopathic polypoidal choroidal vasculopathy
Asians, serous PED +/- subretinal haemorrhages, perimacular lesions
This condition involves branching of choroidal vessels with polypoidal and aneurysmal dilations.
What are the characteristics of surgical third nerve palsy?
Young patient, no cardiovascular risks, pupil involvement, incomplete palsy with progression, multiple cranial nerve palsies, no recovery over time
This condition may indicate a more serious underlying issue compared to microvascular causes.
What are causes of BINASAL hemianopsia?
Retinal: atypical RP, schisis, vascular occlusion, juxto papillary retinochoroiditis, and myopia with peripapillary atrophy.
Optic nerve: glaucoma, disc deuses, chronic papilloedema
What is Choroidermia?
An X-linked recessive degeneration of the choroid affecting RPE and photoreceptors.
What symptoms are associated with Choroidermia?
- Night blindness in childhood/adolescence
- Concentric visual field loss
- Mottled retinal changes progressing to chorioretinal atrophy with scleral exposure
CHoRODoraemia
X linked
Night blindness, peripheral vision loss
What are the types of congenital glaucoma?
- True congenital (40%): occurs in utero
- Infantile glaucoma (55%): develops before 3rd birthday
- Juvenile glaucoma (5%): develops between 3-16 years
What is Nd:YAG laser radiation?
It emits infrared radiation at 1064 nm with helium/neon beam; pulsed laser creates plasma.
What is Kjer optic neuropathy?
A dominant optic atrophy that manifests at ages 5-10 with progressive visual loss until the 20s, stabilizing with mild visual dysfunction and tritanopia.
What is clinically indicated by a high AC/A ratio?
Esotropia greater at near of 10D or more.
What are the sterilization temperatures and times for dry heat?
160°C for 120 minutes.
What are the sterilization parameters for steam?
- 120°C for 15 minutes
- 134°C for 3 minutes
How do local anesthetics penetrate tissues?
They penetrate better when in an alkaline solution.
Where is the globe more vulnerable to trauma?
Temporally.