3. Evaluation-Color Vision
• Optic nerve vs Macular Disease
• Psuedoisochromatic color plates (congenital color
deficiency and acquired optic nerve diseases)
• Other (HRR plates-blue and Yellow , Fansworth-
Munsell D15 Panel)
4. Evaluation-Pupil
• RAPD is the hall mark of optic neuropathy.
• Swinging flash-light test.
• Reverse RAPD (wrong name) if one pupil is dilated
or does not constrict for mechanical causes.
16. Non-Arteritic Anterior Ischemic
Optic Nuropathy (NAION)
• Age> 40.
• Unilateral visual acuity/field loss.
• Disc edema ( initially pallid ) , can be sectoral or diffuse.
• Small cup/disc ratio (anamolous disc).
• Vascular risk factors (diabetes,hypertension, smoking,
hypercholesterolemia).
• Usually remains static but can improve in 42.7 % or
progress over several weeks in 25 %.
19. Arteritic anterior ischemic
optic neuropathy
• Age >70
• GCA symptoms
• Vision loss is often more severe
• Chalky-white swelling of the disc
• Retinal infarcts/cotton wools spots
• Delayed filling IVFA
• Other disc has normal C/D ratio
20.
21.
22.
23. Posterior Ischemic Optic
Neuropathy
• After severe blood loss, intra-operative hypotension, renal
dialysis, severe anemia, spinal procedures, and coronary
bypass surgery.
• Disc are usually normal.
• Pupillary light reflexes assessment.
31. • A 12 year old with history of sudden, sequential, bilateral
vision loss x 4 days.
• First right eye and 1 day later the left eye.
• No photophobia, or redness.
• No fever, headache or neck pain.
• Otherwise healthy.
• No allergies.
Case
32. Case
• Was admitted to Amiri Hospital .
• CT and MRI brain was normal.
• Received IV steroids x 2 days with mild improvement in
vision.
• CBC , ESR Normal.
• Ophthalmology consult.
33. Case
• VA : HM , CF 2 meters.
• Color vision : 0/13 OU.
• Pupils : sluggish OU , Right RAPD
• Motility : Full, orthophoric.
• Orbits : Normal RTR.
• TA : 12 mm/Hg OU.
• SLE : Normal anterior segment , no cells or falre.
41. Leber’s Hereditary Optic Neuropathy
Unilateral painless vision loss.
Usually acute, but some are chronic.
Sequential bilateral involvement in weeks or
months.
6-80 year old.
Central or cecocentral visual field defect.
disk swelling, thickening of the peripapillary retinal
nerve fiber layer and peripapillary retinal
telangectatic vessels.
43. LHON
4 primary mitochondrial genome mutations;
11778, 3460, 14485, 14459.
males > females ratio = 2.5:1.
Spontaneous recovery of vision can occur.
Cardiac conduction defects.
44. Compressive Optic Neuropathy
Thyroid eye disease, meningioma, pituitary
tumors, glioma, aneurysms, Hydrocephalus,
and carniopharyngiomas.
Disc can be pale or normal.
Visual fields defects help localization.
Neuro-imaging is essential.
46. Compressive Optic Neuropathy
• 5%-7% of TED
• Direct compression of the optic nerve at the orbital apex
• Dyschromatopsia , RAPD ( absent if bilateral)
• Disc edema in 40%
• Visual fields
• Often in the active phase of the disease
• Proptosis may be minimal (tight lids)
58. Optic atrophy with other
neurological manifestations
Optic atrophy with spinocerebellar ataxias.
Wolfram syndrome (DIDMOAD).
Fredreich's ataxia.
59. Toxic-nutritional Optic Neuropathy
Tobacco-alcohol amblyopia in alcohol
abusers, smokers, and in nutritional
deficiency.
Vitamin deficiency : thiamine (B1), riboflavin
(B2), Folate , B 12 and B6.
Stop inciting agents and give thiamine.
Recovery is usually slow.
61. Swollen ON in TON
A 35 year old woman underwent a gastric by-pass for weight loss.
Nausea and vomiting, had significant weight loss.
She had no alcohol consumption.
She presented with extra-ocular muscle abnormalities, ptosis, confusion,
ataxia, and responded to IV Thiamine
64. Chiasmal Disorders
• Visual fields respecting vertical meridien
• Most common visual field loss - Bitemporal
Hemianopsia
• Junctional scotoma - lesion at junction of the optic
nerve and chiasm
74. Extrinsic Causes of
Chiasmal Syndrome
• Pituitary adenoma - Apoplexy
• Craniopharyngiona
• Parasellar meningiom
• ICA aneurysm
• Dilated 3d ventricle due obstruction
75. Delayed Vision Loss Post-
Treatment
•Tumor recurrence
•Delayed radionecrosis of the chiasm or optic
nerves
•Chiasmal distortion due to adhesions or
secondary empty sella syndrome, with descent
and traction on the chiasm
•Chiasmal compression from expansion of
intraoperative overpacking of the sella with fat
86. Parietal Lobe Lesions
• “Pie on the floor” homonynous defect.
• Associated neurologic signs and symptoms (e.g.,
hemiplegia, hemisensory loss, visual, or neglect) may be
present.
• Gertsman’s syndrome-dominant lobe (acalculia, agraphia,
finger agnosia, and left right confusion)
• Lesions in the nondominant parietal lobe can produce
contralateral neglect.
88. Occipital Lobe Lesions
• Congruous homonymous hemianopia, possibly sparing the
fixational region .
• A monocular defect of the temporal crescent involving only the
most anterior portion of the occipital
• lobe
• Homonymous lesion sparing the temporal crescent in the eye
contralateral to the lesion
• Homonymous hemianopia that respects both the vertical and
horizontal meridians
92. “Where” Pathway
• Dorsal stream (occipitoparietal): Spatial orientation ,visual
guidance of movement.
• V1 V3-> V5->Parietal and superotemporal cortex.
• Continuation of magnocellular pathway.
• Simultagnosia, optic ataxia, acquired oculomotor apraxia,
and hemispatial neglect.
93. Cortical Blindness
• Due to bilateral occipital lobe lesions.
• Often misdiagnosed as functional vision loss.
• Stroke, severe blood loss, Eclampsia,
hypertension, angiography, CO poisoning,
cyclosporine.
94. Alexia without Agraphia
• Loss of ability to
read but can write.
• Left occipital lobe
and splenium of
corpus callosum.
Notas del editor
Macular disease tend to cause similar decrease in VA and CV. Optic nerve disease can give you 20/20 VA but poor color vision.
Certain types of optic neuropathies (like NAION) tend to spare color vision
I found that most residents and students DON’t do it it very well.
Dim room light , rapid swinging (stun the pupil and catch it in mid-constriction), count 2001 - 2002
Can have the patient look up to prevent accommodation response
Photo-stress Recovery Tests: The patient attempts to read the next larger .Snellen visual acuity line above that for BCVA (eg, 20/25 vs 20/20) as soon as possible. Normal photostress recovery time is less than 30 seconds, but patients with maculopathy or severe carotid artery stenosis show prolonged recovery times, frequently 90–180 seconds or more.
Early on with chasmal syndromes : the optic disc is often normal (no pallor)
Visual fields loss can be advanced with normal optic nerve appearance
Cupping ++
Generally- the more posterior the more congrous, Recent studies have questioned this rule-of-thumb . In aseries of 538 patients, 59% of optic radiation lesions and 50% of optic tract lesions caused congruent homonymous hemianopia.
Ma
Upper quadrant -medial aspect of LGN,
Lower quadrant- lateral aspect of LGN.
Macular fibers- central wedge of LGN (supplied by anterior choroidal artery)
Meyer loop : nerve fiber fascicle around the temporal and anterior horn of the lateral ventricle.
A patient who left temporal lobectomy for seizure . Damage to temporal lobe anterior to Meyer loop does not cause visual field defect.
