Off-tah Flashcards
Involuntarily blink
Pretarsal
Involuntarily blink
Preseptal
Forced lidclosure
Orbital
Involuntary blinking/closure of eyelids–– Functionally disabling Treatment: Botox injection
Blepharospasm/Hemifacial muscle)
Serves as an anatomic barrier between preseptal and orbital structures
Orbital Septum
common infection of the eyelid and periorbital soft tissues
PreseptalCellulitis
Involvement posterior to the septum
RAPD, Proptosis, Limited EOMs, ChemosisTreatment: Intravenous antibiotics,
Orbital Cellulitis
Opening of the eye
Can 3 + sympha
Closing the eye
Cn7
Dense plates of connective tissue that gives structure and serves as a fibrous skeleton to the eyelids
Contains Meibomian glands
Holocrine gland
Tarsus
Lining of conjunctiva
Nonkeratizing squamous epithelium
Contains mucin secreting Goblet cells and accessory glands of Krausse and Wolfring
> Glands of Krause are found in the Glands of fornices
> glands of Wolfring found in the nonmarginal tarsal are borders
»Basal tear secretion
Conjunctiva
Small abscess, caused by acute staph infant of a las follicle and associated gland of Zeus or moll.
External hordeulum
Chronic.non infective lipogranulomatous in inflammation caused by blockage of meibomian gland orifice and stagnation of sebaceous secretions
Chalazion (painless)
Arterial Supply
- Ophthalmic
- E-CA
- Marginal arterial arcade
4.Peripheral arterial arcade
Lymphatic Drainage of eye
Submandibular lymph nodes medially
Superficial preauricular nodes and deep cervical nodes laterally
Excess preseptal skin
Dermatochalasis
main protractor of eyelid
Orbicularis Oculi Muscle
Weakness or inability to close eyelids (lagophthalmos ) Complications: exposure keratopathy
Facial Nerve Palsy
Bell’s Palsy
Involuntary blinking/closure of eyelids––
Functionally disabling
To: Botox injection
Blepharospasm/Hemifacial spasm overactive muscle)
Lower lid laxity
ectropion and entropio
Medial canthal laxity/ disinsertion
ectropion/telecanthus
Muscles of retraction in upper eyelid
- LevatorPalpebrae Superioris Muscle(40mm)
- Levator Aponeurosis(14-20mm)
- SuperiorTarsal Muscle (Muller’s muscle)
All except SuperiorTarsal Muscle (Muller’s muscle) are innervated by CN 3 . The later is sympathetic.
Muscles of retraction in lower lid
- Capsulopalpebral fascia - CN 3
2. Inferior tarsalmuscle - sympathetic
It is a small abscess caused by an acute staphylococcal infection of meibomian gland
- more painful than stye
Internal horduelum
suspends the levatoraponeurosis & part SOtendon
Whitnal’s Ligament:
thinnest bone of orbit and covers the ethmoid sinus)
lamina papiracea
Blowout” Fracture s/s
Symptoms:––
Diplopia (Entrapment of Inferior Rectus) Unable to look up
( Entrapment of Inferior Rectus )
Loss of sensation of the skin of the cheek and gum on the same side (Infraorbital nerve involvement)
Most common wall involved?Orbital Floor into the (the maxillary orbital fat sinus ) explod
What structure opens to Supraorbital notch (Foramen ):
the supraorbital nerve
What structure opens to Infraorbital groove and and canal
Ans : Infra orbital nerve Nasolacrimal canal >Located anteriorly on the medial >It communicates with the inferior meatus of the nose >transmits the nasolacrimal duct
Inferior orbital fissure
maxillary nerve and its zygomatic branch,the inferior ophthalmic vein, and sympathetic nerves
Superior orbital fissure
lacrimal nerve, the frontal nerve, the trochlear nerve, the oculomotor nerve(upper and lower divisions), the abducent nerve, the nasociliary nerve, and the superior ophthalmic vein
Optic canal
optic nerve , ophthalmic artery
loss and of vision, chemosis, exophthalmos (bulging eyes), headaches, and paralysis of the cranial nerves which course through the cavernous sinus
Cavernous Sinus Thrombosis
Receives sensory nerve supply from the lacrimal nerve , a branch of the ophthalmic nerve (CN 1
Both autonomic and sensory innervation
Lacrimal Gland
Uncommon consequence of nerve regeneration after – Bell’s palsy or other damage to the facial nerve .
Efferent fibers of the superior salivary nucleus become improperly connected to the nerve axons of the lacrimal glands
“Crying when salivating or smelling food”
Crocodile Tears Syndrome–
Muscles that Constricts pupil
Sphincter papillae of iris
Innervation - Parasympathetic viaoculomotor nerve
Dilates pupil
Dilator papillae of iris
Innervation:
Sympathetic
Controls shape of lens; inaccommodation, makes lens more globular
Ciliary muscle
Innervation :
Parasympathetic via oculomotor nerve
Eyelid closure
Orbicularis
Innervation:
Facial Nerve (CN VII)
Eyelid opening
Levator palpebrae superioris
Innervation:
CN III, Sympathetic
2/3 of the refractive media of the eye; Transmits light rays; Corneal deturgescense
Cornea
protective layer/tunic of the eye
Sclera
Nourishment layer/tunic
Choroid
Contains receptors cells for light perception (sensory layer/tunic)
Retina
1/3 of the refractive media; Accommodation
Lens
Pupillary reflex; Controls amount of light entering the eye
Iris
Accomodation
PARASYMPATHETIC RESPONSE CN III
The “Near” triad :
The “Near” triad :––Accomodation
Miosis
Convergence
Non- accommodated lens
- Ciliary body relaxes
- Zonular tension increases
- Anterior lens capsule flattens
- Lens more oval ,Lesser AP thickens
- Less diopteric power
*accommodated is the opposite
Helmholtz theory of accommodation
With accommodation - ciliary muscle = contracts -zonular tension = decreases -lens shape = more spherical Lens equatorial diameter = decreases Central anterior lens capsule curvature = steepens Lens dioptric power = increases
the loss of accommodation elasticity of the lens
Presbyopia
40-45 year = more common
Tx : Reading adds
near-sightedness
Image focused in FRONT of retina
Myopia
Tx : DIVERGING/CONCAVE/MINUS lenses
“Farsightedness lenses ”
Image focused at the BACK of the retina
Hyperopia
Tx : CONVERGING/CONVEX/PLUS lenses
Occurs when the cornea (or Lens) has an irregular curvature
Astigmatism
Tx : Cylindrical/ Toric Lenses
Intraocular Pressure
Normally 10-20 mmHg
Meaured by the Applanation Goldmann Tonometer
»> A Relative increase increases the risk of developing Glaucomatous optic neuropathy
leaves the eye at a point 3 mm medial to and slightly above the posterior pole of the (seen in direct ophthalmoscopy as the globe optic disc )
Optic nerve
blind spot
Since there are no visual receptors over the disk, this area of the retina does not respond to light and is known as the
Near the posterior pole of the eye, there is a yellowish pigmented spot
macula
Center of the macula; it is a thinned-out rod free portion of the retina in humans and other primates
fovea
the fovea is the point where visual acuity is greatest
-Organized into layers containing different types of cells and neural processes
Contains the Photoreceptors (Rods and Cones)
Retina
- Light rays must pass through the ganglion cell and bipolar cell layers to reach the rods and cones.
- The pigment epithelium absorbs light rays, preventing the reflection of rays back through the retina
- Ganglion cells retina with are the only output neuron of the their axons forming the optic nerve
Dark Adaptation / Night vision
Contrast sensitivity
- more dense peripherally
Rods
Color vision (Red, Green, Blue) More dense centrally
Cones
The key to initiation 11of the visual cycle is the availability of
cis retinaldehyde (vitamin A)
In deficiency, both the time taken to adapt to darkness and the ability to see in poor light are impaired
“From CIS to TRANS”
PIE on the SKY
PIE-rietal lesion
Pie on the floor
Temporal lesion
Macular Sparing
Occipital lesion
PARASYMPATHETIC response
On Ciliary nerves
1) Ciliary : muscle that controls focusing of the eye lens
(2) Sphincter of the iris constricts the pupil
SYMPATHETIC response
(1) Origin:
Intermediolateral horn cells of the T1 segment of the spinal cord which enter the sympathetic chain and pass upward to the superior cervical ganglion
(2) Postganglionic sympathetic fibers innervate the radial fibers of the iris,as well as several extraocular muscles of the eye
visualizes the back of the eye; ERECT image, MAGNIFIED view
Direct Ophthalmoscope
visualizes the back of the eye; INVERTED image, WIDER view
Indirect Ophthalmoscope
Creates an optical section of retina to view its layers for any pathology
Optical Coherence Tomography
Fluorescent the dye is injected into bloodstream.
Highlights the blood vessels in the back of the eye so they can be photographed
Fluorescein angiography
For QUANTITATIVE
measurement of the visual field
Visual field Perimetry
Invasive bacteria that CAN PENETRATE an intact corneal epithelium? CHaNeLS
Corynebacterium Haemophilus Neisseria Listeria Shigella
ADULT with history of red, painful eye, hyperacute purulent conjunctival discharge ?
Gonococcal Conjunctivitis
Gram (-) intracellular diplococci
• Tx : Ceftriaxone , treat partner, treat coexisting chlamydial infection with Azithromycin
Condition where there is progressive corneal thinning seen in young adults?
Keratoconus
History of allergies, chronic eye rubbing, Marfan’s, Down
Very high myopia and astigmatism
Frequently changes glasses
Tx–EOR correction
Corneal transplant
Farmer/Seaman gradually enlarging wingshaped conjunctival mass encroaching the cornea?
Pterygium UVlight exposure Elastotic Degeneration Stocker’s line : Iron deposits at the head of the pterygium Tx : Excise
Farmer/Seaman gradually enlarging Yellow white deposits at the limbal amorphous interpalpebral conjunctiva
Pingeucula UVlight exposure Elastotic Degeneration Does not encroach cornea Tx : Excise
*** Elastotic Degeneration
Patient with painful Red eye Cement with history of splashing into the eye
Chemical Injury–Cement is alkaline Liquefactive necrosis
Can cause corneal perforation
Tx : IRRIGATION until pH is neutral!!
Patient with painful Red eye muriatic acid with history of splashing into the eye?
Chemical Acid Injury
Coagulative necrosis Causes lesser damage than alkaline injury Tx : IRRIGATION until pH is neutral!!
Patient with history of blunt trauma. Diffuse conjunctival redness
Subconjunctival hemorrhage
-bleeding from a small blood vessel in the outer layer of the eye
DOES NOT cause a decrease in vision Associated with trauma or high blood pressure Self limiting
Patient with history of blunt eye trauma just a few hours ago. Complains of diplopia , and limited eye movement • Impression?
• Orbital wall fracture
Posteromedial Floor : MC wall involvement
Inferior rectus : MC entrapped muscle
Needs urgent repair if with nerve/muscle involvement .
Adult with Diplopia, Bulging eyes , cant look up. Impression?
Thyroid Eye Disease (TED)
Can occur even in euthyroid or hypothyroid state
MC Cause of unilateral bilateral and proptosis in ADULTS
Inferior Rectus: MC involved EOM
Imaging: Tendon sparing Muscle hypertrophy
Tx : Steroids, Immunosuppressants , Surgery
Painful red eye with ciliary injection
Photophobia, Blurred vision, Presence of cells/flares • in the anterior chamber. Diagnosis?
Acute Anterior Uveitis
Associated with autoimmune diseases i.e. JIA, RA, SLE, Sarcoidosis
To steroids
Sudden headache, blurred vision with halos of light. Fixed dilated pupil with hazy cornea ?
Acute Angle Glaucoma closure Pupillary block mechanism High IOP!! Initial Tx : Acetazolamide Definite Tx : Laser iridotomy
Visual field defects characteristic of glaucomatous optic nerve damage?
Respects the HORIZONTAL midline
Arcuate scotomas
Corresponds to the retinal nerve fiber layer
Visual field defects that are of neurologic origin?
Respects the VERTICAL midline
May have other signs such as weakness
Young female, Sudden BOV , Pain on eye movement very poor color vision , but VA is 20/30
Optic neuritis
May or may not have coexisting Multiple sclerosis
2/3 with normal looking nerve; pale nerve : 1/3
MRI can be done to check for demyelinating white matter lesions
Tx Observe , Oral steroids (Optional)
Young Obese , enlarged blind woman, Severe spot, headache Bilateral Papilledema but normal BP diplopia • • •
Idiopathic Intracranial Hypertension increased detectable ICP without cause ( Pseudotumor cerebri)
Dx Test:Lumbar puncture ,MRI is normal
Tx : Weight loss, Acetazolamide, Optic nerve fenestration / CSF diversion
Elderly, Severe headache , Bilateral Papilledema, Retinal hemorrhages and h igh BP •
Hypertensive Retinopathy
Always check BP in cases of bilateral disc swelling
Tx : Control BP, Refer to IM
Adduction deficit with contralateral abduction nystagmus . Where is the lesion?
Internuclear Ophtalmoplegia (INO) Medial longitudinal Fasciculus (MLF) Lesion ipsilateral to adduction deficit Can be bilateral (WEBINO)
Blurred vision plus history of anosmia, infertility, menstrual changes, mood changes. Where is the lesion?
Pituitary Adenoma / Chiasmal tumor Bitemporal hemianopsia
Initially involves superior fields
Tx: Bromocriptine
Surgical decompression
Elderly Caucasian, sudden loss of vision with severe headache, pain on chewing and combing his hair.
Giant Cell Arteritis Hallmark: Jaw claudication Can cause bilateral blindness Labs: Elevated CRP/ESR Dx : Temporal artery biopsy -granulomatous inflammation of medium to large sized vessels Tx : Steroids
Anisocoria greater in DIM light?
Horner’s syndrome Problem in sympathetic pathway Triad––Miosis,Ptosis,Anhidrosis Dx : Cocaine test Causes: Children: Brachial plexus injury Adults: Pancoast tumor, Carotid artery Dissection, Stroke
Anisocoria greater in BRIGHT light?
Adie’s tonic pupil
Parasympathetic : response is impaired Dx Pilocarpine test
Patient with diplopia and ptosis that occurs later on the day and sometimes improves spontaneously
Ocular Myasthenia Gravis
Variable fatiguiability
Tx :Steroids
Young adult with sudden diplopia and ptosis,Headache,dilated pupil on one side. Impression?
CN 3 Palsy involving pupil “Down and out” Eye Posterior communicating Artery Aneurysm until proven otherwise! Dx : CTA, MRA Tx : Surgery i.e • clipping
Elderly diabetic with poor vision and a very opacified lens.
Diabetic Cataract
Sorbitol: Sugar accumulating in the lens Aldose Reductase : limiting step of the reduction rate of glucose to sorbitol
Water goes inside lens via osmosis and gets trapped “Sugar Cataract”
Lens is dislocated or not centered? • •
Lens Subluxation / Ectopia Lentis Associated conditions– Marfan’s Homocystinuria Aniridia Weill-Marchesani syndrome Sulfite oxidase deficiency
Adult with Sudden Painless loss of vision . You see cherry red spot retina?
-Central retinal artery occlusion •Irreversible loss of vision after 90 min Other causes of cherry red spot Taysachs Niemann Pick Sandhoff disease GM1 and GM2 gangliosidoses
Newborn with a Cats eye reflex
- Retinoblastoma
- Long arm of Chromosome 13 Pathology: Flexner wintersteiner cells
Patient underwent uncomplicated cataract surgery . A few days later developed painful red eye and loss of vision
Postoperative Endophthalmitis
MC Etiology: Staph Epidermidis
Signs: Hypopyon , red eye, hazy cornea, Cells/flares
Tx : Intravitreal Antibiotics, Vitrectomy
Antiglaucomadrugs:
Increase outflow:
Latanoprost , Pilocarpine
Decrease aqueous production •
Timolol , Acetazolamide
Decrease vitreous volume •
Mannitol, glycerol
Both decrease production and increase outflow •
Brimonidine