Opthalmoscopic Abnormalities Flashcards
Arteriovenous Nicking. What is it?
<ul> <li>Indentation (nicking) of retinal veins by stiff (arteriosclerotic) retinal arteries </li> <li>Commonest cause is chronic hypertension</li> <li>Valuable sign of chronic systemic hypertension that has also caused damage to arteries elsewhere in body (heart, kidneys, brain) </li> </ul>
Arteriovenous Nicking. How does it appear?
<ul> <li>At <a>arteriovenous crossing points</a>, retinal vein is deviated and narrowed by overlying retinal artery </li> </ul>
Arteriovenous Nicking. What else looks like it?
<ul> <li>Nothing</li> </ul>
Arteriovenous Nicking. How do you manage it?
<ul><li>Using ophthalmoscope, find these vessels at their emergence from optic disc and follow them as far out as you can, looking for arteriovenous nicking, which is usually found within 5 disc diameters of optic disc </li> <li>Measure blood pressure and inquire after other arteriosclerotic risk factors</li> </ul>
Arteriovenous Nicking. What will happen?
<ul> <li>Uncontrolled systemic blood pressure has severe health consequences</li> </ul>
Branch Retinal Artery Occlusion . What is it?
<ul> <li>Ischemic swelling of portion of retina served by occluded branch of retinal artery</li> <li>In this case, occlusion occurred because of embolus, visible as <a>yellow-white particle</a> at vessel bifurcation</li> <li>Patient reported sudden painless cloudy vision in upper field of vision of left eye</li> </ul>
Branch Retinal Artery Occlusion . How does it appear?
<ul> <li>History of sudden painless loss of upper field leads you there</li> <li>Ischemic retina has lost its transparency, now appearing gray instead of transmitting orange color of underlying choroid</li> </ul>
Branch Retinal Artery Occlusion . What else looks like it?
<ul> <li><a>Inflammatory retinal infiltrate</a>, BUT...would have fuzzier edges</li><li><a>Choroidal tumor</a>, BUT...would be more subtle color change</li> <li><a>Retinal detachment</a>, BUT...would be more extensive</li> </ul>
Branch Retinal Artery Occlusion . How do you manage it?
<ul> <li>Interpret this finding as indication of embolism from cervical carotid artery or heart</li> <li>Refer to ophthalmologist urgently if vision loss came on recently</li> </ul>
Branch Retinal Artery Occlusion . What will happen?
<ul> <li>Further embolization causing stroke could be imminent and potentially prevented with urgent medical attention</li> </ul>
Congenitally Elevated Optic Disc Anomaly. What is it?
<ul> <li>Optic disc elevation present from birth</li> <li>Probably caused by small scleral opening so that optic nerve axons are tight fit</li> <li>Other dysplastic features may contribute to elevation</li> <li>Usually does not disturb vision</li> </ul>
Congenitally Elevated Optic Disc Anomaly. How does it appear?
<ul> <li>There is no physiologic cup; compare to <a>normal physiologic cup</a></li> <li>Nerve fiber layer adjacent to optic disc not obscured as it would be in acquired causes of optic disc elevation ("<a>papilledema</a>")</li> <li>No <a>optic disc surface hemorrhages</a> or <a>cotton wool spots</a></li> <li>Dome-shaped rather than <a>doughnut-shaped optic disc elevation</a>, characteristic of papilledema</li> <li><a>Optic disc drusen</a>-glistening white chunks sometimes appear on optic disc surface; they are calcified mitochondria extruding from axons</li></ul>
Congenitally Elevated Optic Disc Anomaly. What else looks like it?
<ul> <li><a>Papilledema</a></li> <li>Other causes of acquired optic disc elevation</li> </ul>
Congenitally Elevated Optic Disc Anomaly. How do you manage it?
<ul> <li>Refer to ophthalmologist non-urgently if this is isolated finding in asymptomatic patient</li> <li>Refer urgently if patient has symptoms to suggest vision loss or increased intracranial pressure</li> </ul>
Congenitally Elevated Optic Disc Anomaly. What will happen?
<ul> <li>Even experienced eye care providers cannot always distinguish congenitally elevated optic disc anomaly from acquired optic disc elevation by ophthalmoscopy alone, therefore...</li> <li>Non-ophthalmoscopic clues must be used to make this distinction</li> <li>Examiners will mistake congenitally elevated optic disc elevation for papilledema over and over</li> <li>Congenitally elevated optic disc elevation with drusen may be associated with visual field loss that may be progressive</li></ul>
Copper-Wiring and Silver-Wiring. What is it?
<ul><li>Thickening of walls of retinal arterioles from chronic hypertension</li> </ul>
Copper-Wiring and Silver-Wiring. How does it appear?
<ul> <li>Retinal arterioles appear orange or yellow instead of red ("<a>copper wiring</a>")</li> <li>Retinal arterioles look white if they have become occluded ("<a>silver wiring</a>")</li> <li>Retinal arterioles indent retinal veins as they cross each other ("<a>arteriovenous nicking</a>")</li> </ul>
Copper-Wiring and Silver-Wiring. What else looks like it?
<ul> <li>Nothing—your challenge is to recognize this sign! </li> </ul>
Copper-Wiring and Silver-Wiring. How do you manage it?
<ul><li>Recognize these signs of chronically elevated blood pressure</li> <li>Measure blood pressure, but even if not currently elevated, assume it has been elevated in past</li> <li>Make sure blood pressure is controlled </li> </ul>
Copper-Wiring and Silver-Wiring. What will happen?
<ul> <li>Poor blood pressure control has adverse consequences—heart attack, stroke, and kidney disease among them</li> </ul>
Cotton Wool Spots. What is it?
<ul> <li>White spots on retinal surface caused by microinfarction</li> <li>Usually do not produce vision loss unless large or near fovea </li> <li>Causes are hypertension, diabetes, HIV, lupus, severe anemia or thrombocytopenia, hypercoagulable states, connective tissue disorders, viruses, lues, Behçet, Purtscher, and many others</li> </ul>
Cotton Wool Spots. How does it appear?
<ul> <li>Like dabs of white paint within 5 optic disc diameters of optic disc</li> </ul>
Cotton Wool Spots. What else looks like it?
<ul> <li>Retinal drusen, chorioretinal atrophy, inflammatory retinal infiltrate, myelinated nerve fibers</li> <li>These <a>yellow-white things in retina</a> are difficult to distinguish from each other</li> </ul>
Cotton Wool Spots. How do you manage it?
<ul> <li>Refer to ophthalmologist non-urgently if incidental finding, urgently if associated with active illness or new vision loss</li> </ul>
Cotton Wool Spots. What will happen?
<ul> <li>Depends on underlying cause</li> </ul>
Myelinated Nerve Fibers. What is it?
<ul> <li>White patches on retinal surface that often surround optic disc </li> <li>May cover large area, as in this picture</li> <li>Congenital anomaly in which retinal nerve fibers are mistakenly myelinated </li> <li>Does not interfere with vision </li> </ul>
Myelinated Nerve Fibers. How does it appear?
<ul><li>Like <a>white paint</a> spread over retinal surface that obscures vessels </li> </ul>
Myelinated Nerve Fibers. What else looks like it?
<ul> <li><a>Cotton wool spots</a>, BUT...myelinated nerve fibers are larger and denser and almost always connected to optic disc</li> <li><a>Retinal infiltrates</a>, BUT...they often have overlying vitreous haze</li> <li><a>Papilledema</a>, BUT... myelinated nerve fibers are much whiter and extend farther out on retina </li> <li><a>Hard exudates</a>, BUT...they are smaller and yellower and located farther from optic disc</li><li>Check out <a>yellow-white things in the retina</a></li></ul>
Myelinated Nerve Fibers. How do you manage it?
<ul> <li>If you are confident of diagnosis, reassure patient </li> <li>If not, refer to ophthalmologist non-urgently if no new symptoms </li> </ul>
Myelinated Nerve Fibers. What will happen?
<ul> <li>Stable condition that does not affect vision</li> <li>Important mainly because it alarms examiners</li> </ul>
Old Retinal Vascular Occlusion. What is it?
<ul> <li>White, thready retinal vessels that look like twisted pipe cleaners </li> <li>There is no retinal edema to indicate recent infarction because these vessels were occluded long ago</li> <li>Many conditions cause this, including hypertension, connective tissue disease, Behçet disease, sarcoidosis</li> <li>Patient has patchy scotomas in visual field corresponding to infarcted retina<br></br> </li> </ul>
Old Retinal Vascular Occlusion. How does it appear?
<ul><li><a>White segments</a> interrupt red blood column in retinal vessels</li> </ul>
Old Retinal Vascular Occlusion. What else looks like it?
<ul> <li>Nothing</li> </ul>
Old Retinal Vascular Occlusion. How do you manage it?
<ul> <li>Interpret this as sign of old vascular occlusion </li> <li>Blood vessels in other body tissues are probably similarly affected but you cannot see them </li> </ul>
Old Retinal Vascular Occlusion. What will happen?
<ul> <li>This finding may be clue to systemic vasculopathy which, if active, will go on to destroy tissue elsewhere in body</li> </ul>
Optic Disc Pallor. What is it?
<ul> <li>Whiteness of optic disc neuroretinal rim on ophthalmoscopy</li> <li>Sign of death of optic nerve axons</li> <li>Appears weeks to months after axons have died</li> <li>Many diseases can cause this</li> </ul>
Optic Disc Pallor. How does it appear?
<ul> <li>In normal eyes, <a>physiologic cup</a> in center of optic disc appears white, but <a>neuroretinal rim</a> appears orange on ophthalmoscopy</li> <li>In optic disc pallor, neuroretinal rim appears <a>white instead of orange</a></li> <li>Color change may be subtle</li> </ul>
Optic Disc Pallor. What else looks like it?
<ul> <li><a>Normal optic disc</a>, whose temporal portion is whiter than its nasal portion</li> <li><a>Optic disc of myopic patients</a>, whose temporal portion is even whiter than in non-myopic patients</li> <li>Distinguishing pathologic optic pallor from normal variation and myopic optic discs is very challenging and best left to ophthalmologist</li> </ul>
Optic Disc Pallor. How do you manage it?
<ul> <li>If you suspect optic disc pallor, refer non-urgently to ophthalmologist</li> </ul>
Optic Disc Pallor. What will happen?
<ul> <li>Optic disc pallor means that optic nerve axons have been damaged in variety of disorders</li> <li>Delayed diagnosis may lead to irreversible blindness</li> </ul>
Papilledema. What is it?
<ul> <li>Swelling of optic disc caused by increased intracranial pressure </li> </ul>
Papilledema. How does it appear?
<ul> <li>Patient may report transient black-outs of vision, especially upon standing </li> <li>Patient need not report headache or other non-visual symptoms </li> <li>Optic disc margins <a>indistinct</a></li> <li>Optic disc elevated above retinal surface </li> <li>These signs may be ophthalmoscopically subtle </li> <li>In acute phase, may see <a>hemorrhages</a> and <a>cotton wool spots </a></li> <li>In <a>chronic phase</a>, optic disc elevation and blurred margins, but no hemorrhages or cotton wool spots</li> <li> In <a>atrophic phase</a> (optic nerve axons have died), optic disc shows mixture of pallor and swelling</li> <li>Vision usually normal or near normal unless atrophy has set in </li> </ul>
Papilledema. What else looks like it?
<ul> <li><a>Congenitally elevated optic disc</a>, but features of dysplasia usually present and visual function usually preserved</li> <li><a>Non-arteritic ischemic optic neuropathy</a>, but patient reports acute unilateral vision loss, and optic disc swelling usually unilateral</li> <li>Arteritic ischemic optic neuropathy in <a>giant cell arteritis</a>, but patient usually has systemic symptoms </li> <li>Optic neuritis, but patient reports acute vision loss and sometimes periocular pain in affected eye on gaze from side to side</li> <li>Compressive optic neuropathy from mass in orbit or optic canal, but lesion visible on imaging </li> <li>Infiltrative optic neuropathy from metastatic cancer or systemic inflammation like sarcoidosis, but there is usually evidence of cancer or inflammation elsewhere </li> <li>Leber hereditary optic neuropathy, but usually unilateral and optic disc is hyperemic</li><li><a>Central retinal vein occlusion</a>, but that has more hemorrhage and less optic disc swelling</li><li><a>Terson syndrome</a>, but only in setting of severe body trauma or pancreatitis</li> <li>Distinguishing these causes of optic disc edema is challenging</li></ul>
Papilledema. How do you manage it?
<ul> <li>Refer emergently (within 24 hours) to ophthalmologist if you detect elevated optic discs and patient has visual, neurologic, or constitutional symptoms </li> <li>Refer urgently (within 48 hours) if you detect elevated optic discs in an asymptomatic patient </li> </ul>
Papilledema. What will happen?
<ul> <li>Ophthalmologist will try to determine cause of elevated optic disc </li> <li>If papilledema is suspected, patient will undergo immediate neurologic examination and brain imaging </li> <li>If arteritic ischemic optic neuropathy is suspected, patient will undergo prompt intensive corticosteroid treatment and temporal artery biopsy</li> <li>If compressive optic neuropathy is suspected, patient will undergo orbit and brain imaging </li> <li>If infiltrative optic neuropathy is suspected, patient will undergo orbit/brain imaging, lumbar puncture, and search for evidence of metastatic cancer or systemic inflammation </li> <li>If Leber optic neuropathy is suspected, patient will undergo blood testing for appropriate mitochondrial gene mutations </li> <li>Undiagnosed chronic papilledema may lead to death of optic nerve axons and dreadful and irreversible vision loss, therefore... </li> <li>Early detection of papilledema is critical, not only to discover and treat its cause, but to relieve pressure on optic nerves </li> </ul>
Pathologic Optic Disc Cupping. What is it?
<ul><li><a>Thinning of optic disc neuroretinal rim</a> so that optic disc appears pathologically cupped (excavated)</li> <li>Usual cause is <a>glaucoma</a></li> <li>Glaucoma causes slow death of optic nerve axons and their supporting glia partly because of chronically high intraocular pressure</li> <li>Visual fields eventually become constricted, but only when neuroretinal rim is very thinned</li> <li>Intraocular pressure must be controlled to forestall worsening of vision </li> </ul>
