HEENT 6- Flashcards
Retinal detachment
Separation of the sensory retina from the pigment epithelium and underlying choroid
Traction or tear of retina allows what?
Fluid to accumulate between the two layers
Retinal detachment can result in what?
Ischemia and rapid progressive photoreceptor degeneration. Permanent blindness can occur if macula is detached
Photoreceptors are most highly concentrated in what?
Fovea, which is within the macula
Uncomplicated spontaneous retinal detachments can be cured how?
With one peration or proceudre
Spontaneous detachments are usually what?
Bilateral
Risk factors for retinal detachment
Myopia (near-sighted), Previous ocular surgery most common***
Fluoroquinolones, trauma, family history, Marfan disease
Causes of retinal detachment
Retinal tears or holes (spontaneous or traumatic), traction on the retina caused by systemic influences (diabetic retinopathy), tumors, exudative process (infection, malignancy)
Symptoms of retinal detachment
Increasing # of floaters, flashes of light in visual fields, shower of black spots in visual fields, curtain spreading over visual field, cloudy or smoky vision
Differential diagnosis of retinal detachment
Vitreous hemorrhage, vitreous inflammation, ocular lymphoma, intraocular foreign body
What will a retinal detachment look like on an ophthalmoscopic exam?
“billowing sail” or “ripple on a pond”
Treatment of retinal detachment
Consult ophthalmology ASAP! Drain the subretinal fluid, laster photocoagulation, cryotherapy to sclera, pneumoretinopexy, scleral buckely placement, vitrectomy surgery
What is photocoagulation
Numbing drops, retinal break is localized, 2-3 rows of 200 micron size laser burns (heat energy). Takes 2 weeks for body to form adhesions over burns
What is cryotherapy (cryoretinopexy)
Lidocaine injected first, cryoretinpexy probe is placed on conjunctiva under break, freezing ball is created at tip of probe, freezes through sclera, choroid and retina. Also take 2 weeks to form adhesions
What is pneumoretinoplexy?
For large retinal detachments, do the cryoretinoplexy and follow that with an injection of intravitreal gas bubble, the retinal detachment is pushed back by the gas, adhesion is then formed
What is scleral buckle placement?
Retrobulbar injection of lidocaine first, cryoretinpexy is preformed, an explant is sutured to the sclera, it indents the wall of the eye, closing the retinal breaks
What is vitrectomy surgery?
Removes tractional components and is only performed if the fovea is detached or appears imminently detached
Optic neuritis
Inflammatory disease of the optic nerve, characterized by a normal fundus exam initially
What is optic neuritis strongly associated with?
Demyelinating diseases like MS
Causes of optic neuritis
MS, sarcoidosis, neuromyelitis optica, herpes zoster, systemic lupus erythematosus
Symptoms of optic neuritis
Unilateral loss of vision* developing over few days, and pain exacerbated by movement*
Loss of vision characterization with optic neuritis
Usually central, loss of color vision. Visual acuity improves within 2-3 weeks
Management of optic neuritis
Brain MRI: assess for MS, consult neuro-ophthalmologist, systemic corticosteroids (controversial)
Multiple demyelinating plaques
Treatment with interferon Beta-1a can retard the development of more lesions, Interferon is a biologic that fights infection and is used to treat MS, injectable
Optic Neuritis summary
Painful, monocular vision loss, fundoscopic exam is intially normal, MRI is indicated of brain, consult specialist!
What is papilledema?
PE finding during a fundoscopic exam, loss of definition of the optic disc (edema of the head of the optic nerve)
Vessels are pushed forwad, veins dilated
Where does pipilledema occur initially?
Superiorly and inferiorly and then nasally and temporally
Causes of papilledema
ICP transmitted along the optic nerve (only true cause), Hypertensive Retinopathy (often described as papilledema)
Causes of increased ICP
Intracranial mass lesions, cerebral edema, hydrocephalus (increased CSF production or decreased absorption), obstruction of venous flow, intracranial HTN (pseudotumor cerebri)
Symptoms of increased ICP
Headache thats worse lying down and upon awakening in morning, N/V, binocular horizontal diplopia, pulsatile machinery-like sound in ear, brief transient visual blurring
What are the 3 stages of papilledema?
- Early
- Fully developed
- Chronic
Early papilledema
Loss of spontaneous venous pulsations, optic cup is retained early on
Fully developed papilledema
Optic disc elevated, cup is obliterated, disc margins are obscured, blood vessels buried, engorged veins, flame hemorrhages, cotton wool spots
What are the cotton wool spots a result from (papilledema)
Nerve fiber infarction
Late chronic papilledema
Cup remains obliterated, hemorrhagic and exudative components resolve, nerve appears flat with irregular margins, disc pallor
Diagnostic testing for papilledema
MRI or CT, lumbar puncture (to check opening pressure >180), visual field testing (to detect subclinical abnormalities and monitor changes over time)
Management of papilledema
Reducing intracranial pressure (for intracranial HTN)
Management of elevated ICP
Continuous ICP monitoring, osmotic therapy and diuresis (reduce brain volume), hypertonic saline (reduces ICP early), Glucocorticoids (reducing swelling for tumors and infections)
Other ways to manage elevated ICP
Hyperventilation, barbiturates (reduces brain metabolism and cerebral blood flow), removal of CSF with a shunt, decompressive craniectomy
Clinical features of idopathic intracranial HTN
N/V, HA, blurred vision, CN VI paresis/horizontal diplopia, bilateral papilledema, spontaneous venous pulsations are absent, visual field defects
Management of IIHTN
Weight loss, serial lumbar punctures, Acetazolamide, high dose corticosteroids if rapid vision loss, surgery for severe refractory cases
Retinal vein occlusions
HTN, diabetes, sickle cell anemia, conditions that slow venous blood flow. Reduction in flow results in neovascularization between retinal and vitreous humor, new vessels prone to hemorrhage
Retinal artery occlusion
Acute, painless loss of monocular vision, considered a form of stroke
What are the two types of retinal artery occlusion?
- Central retinal artery occlusion
2. Branch retinal artery occlusion
Risk factors for retinal artery occlusion
Carotid artery atherosclerosis, cardiogenic embolism, giant cell arteritis, sickle cell disease, hypercoagulable states, carotid artery dissection