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.
What is ACUTE Idiopathic BLIND SPOT ENLARGEMENT (AIBSE)?
Acute, unilateral enlargement of blind spot, photopsias, minimal fundoscopic changes, subtle retinal irregularities, OCT disruption of ellipsoid
Involves a patient who is young to middle-aged, part of AZOOR
FFA hyperauto, FFA late disc staining
What characterizes BEHÇET’S syndrome?
Usually bilateral, recurrent acute explosive inflammatory episodes lasting 2-4 weeks, non-granulomatous anterior uveitis with hypopyon, posterior vascular occlusive episodes with retinal haemorrhages and vitreous inflammation
Consider viral retinitis in differential diagnosis
Systemic: oral + genital ulcers, diarrhoea with blood, inflammatory bowel
What is the earliest sign of HIV infection?
p24 core protein in blood
Diagnosis of AIDS is based on clinical grounds or CD4 count < 200.
What are the components of BASSEN-KORNZWEIG syndrome?
Abetalipoproteinemia, Retinitis pigmentosa, Acanthocytosis, Ataxia
It is associated with lipid metabolism disorders. Treatment with Vitamin A and E.
What are the characteristics of ARGYLL-ROBERTSON pupil?
Lesion in dorsal midbrain, small irregular pupils, normal speed of constriction, poorly responsive to pharmacological dilation
Causes include syphilis, multiple sclerosis, alcoholism, trauma, and water intoxication.
What is KOHN-RAMONO syndrome associated with?
Primary amenorrhea
Blepharophimosis, thelecantus, ptosis, epicanths inversus
What was the finding of the Optic Neuritis Treatment Trial regarding oral steroid treatment?
No difference in recovery speed
IV steroids faster recorvery and lower rate of MS in 1 year
No significant effect observed on recovery speed or outcomes in multiple sclerosis patients after 5y
Fill in the blank: The earliest sign of infection in AIDS is _______.
p24 core protein in blood
True or False: BEHGET’S syndrome is characterized by unilateral episodes.
False
What is Eales disease?
A condition characterized by inflammatory retinal vasculopathy leading to peripheral retinal ischemia, neovascularization, and vitreous hemorrhages.
Eales disease is commonly seen in young males aged 20-40 in South Asia/India and is associated with tuberculosis exposure.
What are the common characteristics of Eales disease?
It can present unilaterally or bilaterally and is associated with tuberculosis exposure.
The condition results in significant complications such as neovascularization.
What type of retinal injuries can occur post trauma?
Inferotemporal dialysis and superonasal dialysis, along with tears such as giant retinal tear and four pop tear.
These injuries are often related to blunt trauma.
Where is the abducens nerve located?
Ventral, close to the facial nerve at its origin, near the brainstem and anterior inferior cerebellar artery.
The abducens nerve changes from a vertical to a horizontal course on the apex of the petrous bone.
Describe the course of the abducens nerve.
Courses upward in the pontine cistern.
This pathway is critical for controlling lateral eye movement.
What is retinoschisis?
A condition characterized by the splitting of retinal layers, which can be classified into two types: male and female retinoschisis.
Retinoschisis can lead to vision problems due to the separation of the retina.
What is a capillary hemangioma?
A benign tumor that appears shortly after birth, characterized by abnormal growth of blood vessels, which can be superficial or deep.
It has a higher blood flow compared to cavernous hemangiomas and can resolve over time.
What percentage of capillary hemangiomas completely regress by 4 years?
40% complete regression.
Treatment may involve topical or systemic beta-blockers.
What is congenital esotropia?
A condition typically characterized by an angle greater than 30 prism diopters with dissociated vertical deviation in 60-70% of cases, often associated with mild hyperopia.
Onset is usually by 6 months, and it can involve cross-fixation and latent nystagmus.
What is the Ishihara test used for?
To detect red-green color vision defects.
This test is commonly used in clinical settings to assess color vision.
What syndrome is associated with mitochondrial inheritance and includes symptoms like ptosis and ophthalmoplegia?
Kearns-Sayre Syndrome
Symptoms also include pigmentary retinopathy, diabetes, deafness, and conduction defects
What is the treatment for Kearns-Sayre Syndrome?
Coenzyme Q10, vitamin E, vitamin C, and B vitamins
These supplements are aimed at managing the symptoms
What is the inheritance pattern of Myotonic Dystrophy?
Autosomal Dominant (AD)
This condition can lead to various complications including respiratory insufficiency and proximal muscle weakness
Name a common presentation of Myotonic Dystrophy.
Ptosis, ophthalmoplegia, strabismus, and pigmentary retinopathy
Other symptoms include hypotonia, mental deterioration, and sub-fertility
What does Fundus Albipunctatus refer to?
Congenital stationary night blindness
It is a retinal condition affecting night vision
What characterizes Morning Glory Syndrome?
Unilateral congenital enlargement of the optic disc with a conical deep excavation
It may also involve overlying fibrovascular proliferation and retinal folding
What visual acuity test is used for children under 2 years?
Preferential looking tests
This method assesses visual acuity based on the child’s preference for looking at different stimuli
What is a potential misdiagnosis for eosinophilic granuloma in children?
Retinoblastoma
Unlike retinoblastoma, eosinophilic granuloma does not present with calcifications
What condition is characterized by divergence insufficiency?
Esotropia with worse deviation at distance
This condition is typically comitant and may not present with esotropia at near
What causes Diffuse Unilateral Subacute Neuroretinitis?
Various retinal worms, primarily Baylisascaris
Symptoms include disc edema, optic atrophy, and diffuse pigmentary changes
What is the treatment for Diffuse Unilateral Subacute Neuroretinitis?
Photocoagulation of the retina
This is aimed at managing the retinal damage caused by the infection
