Chapter 14. Vision Loss

Question 1

Question 14-1: 
A 36-year-old man complains of  intermittent monocular visual loss. On questioning, he notes halos around lights, but has no eye pain. Which is the most likely diagnosis? 
A.  Optic neuritis 
B.  Amaurosis fugax 
C.  Glaucoma 
D.  Migraine

Answer 1

Answer 14-1: C.
Subacute attacks of angle-closure glaucoma
can present with intermittent monocular visual
loss. and often occur without pain. Halos
around lights due to corneal edema are a
common clue, though patients may not report
this effect unless directly asked

Question 2

Question 14-2:
Which of the following statements are true regarding junctional scotoma?
A. Visual field defects are identical in the two eyes
B. Most common cause is migraine
C. Is seldom symptomatic
D. The cause is usually a lesion at or near the chiasm
E. All are true

Answer 2

Answer 14-2: D.
Junctional scotoma is due to a lesion at or near
the chiasm acd produces visual field defects
which are not congruent. Tumors are the most
common causes, especially pituitary lesions
rising out of the sella. Part of the visual field
defect may be asymptomatic, so careful
monocular visual field teSting is required to
detect the deficit. but it would not be expected
for the entirety of the deficit to be unrealized.

Question 3

Question 14-3:
A patient with a history of optic neuritis notes that with fever, the vision in the affected eye deteriorates. What is the most likely clinical explanation?
A. The illness produces recurrent episodes of optic neuritis.
B. The fever produces exacerbation of the pre-existing demyelinating damage.
C. The fever and the exacerbation of visual loss are coincidentaL
D. The patient’s observations are psychosomatic.

Answer 3

Answer 14-3: B.
Uhthoffs phenomenon is deterioration of
vision due to fever in patients with a previous
history of optic neuritis. Although optic
neuritis is the classic cause, it can also be seen
with other optic neuropathies

Question 4

Question 14-4: 
A 70-year-old man presents with the sudden onset of monocular visual loss. The defect is central with peripheral vision spared. Examination shows retinal hemorrhages in  the affected eye. Which  is  the most likely diagnosis? 
A.  Optic neuritis 
B.  Acute glaucoma 
C.  Central retinal artery occlusion 
D.  Central retinal vein occlusion 
E.  None of  the above

Answer 4

Answer 14-4: D.
Central retinal vein occlusion typically
produces sudden onset of visual loss which
affects central vision, sparing peripheral
vision. The hemorrhagic retinopathy helps to
differentiate this from central retinal artery
occlusion which shows opacification of the
retinal nerve fiber layer with a cherry-red spot
at the macula. In addition, arterial lesions
produce complete or altitudinal or quadran tic
defects rather than central loss. The sudden
onset is also more typical of a vascular lesion
rather than optic neuritis or glaucoma.

Question 5

Question 14-5:
Which of the following statements is true regarding drusen of the optic nerve?
A. Patienta seldom have detectable visual field loss
B. Arcuate visual field defects and enlargement of the blind spot are common
C. Drusen is due to myelination of optic nerve axons within the eye
D. Loss of central vision with drusen is always benign

Answer 5

Answer 14-5: B.
Visual field defects are seen in about 75% of
patients with optic nerve drusen. Common
field defects are arcuate defects, sectorial
scotomas, and enlargement of the blind spot
Central visual loss is uncommon and when
present indicates a need to consider other
causes of visual loss. Drusen are due to
extracellular deposition of plasma proteins,
can compress the optic nerve, and are not
myelinated axons - this is a different
condition

Question 6

Correlate the visual field defect with 
the appropriate anatomic structure. 
A.  Left retina 
B.  Optic chiasm 
C.  Right optic nerve 
D.  Left temporal optic radiations 
E.  Left parietal optic radiations 
F.  Left occipital cortex 

Question 14-6:
Bitemporal hemianopia.

Answer 6

Answer 14-6: B.
Lesion at the optic chiasm affects the crossing
fibers, thereby producing bitemporal
hemianopia. Since the lesion is rarely exact,
the visual field loss from a lesion in this area
is commonly irregular

Question 7

Correlate the visual field defect with 
the appropriate anatomic structure. 
A.  Left retina 
B.  Optic chiasm 
C.  Right optic nerve 
D.  Left temporal optic radiations 
E.  Left parietal optic radiations 
F.  Left occipital cortex 

Question 14-7:
Right homonymous superior quadrant defect.

Answer 7

Answer 14-7: D.
A right superior quadrant defect is due to a
defect in inferior optic radiations in the
temporal lobe. The defect is often not an exact
quadrant, with the extent of the defect
depending on the size and location ofthe
lesion

Question 8

Correlate the visual field defect with 
the appropriate anatomic structure. 
A.  Left retina 
B.  Optic chiasm 
C.  Right optic nerve 
D.  Left temporal optic radiations 
E.  Left parietal optic radiations 
F.  Left occipital cortex 

Question 14-8:
Hemianopsia.

Answer 8

Answer 14-8: F.
A complete homonymous hemianopia is
commonly due to a lesion of the occipital
cortex.

Question 9

Correlate the visual field defect with 
the appropriate anatomic structure. 
A.  Left retina 
B.  Optic chiasm 
C.  Right optic nerve 
D.  Left temporal optic radiations 
E.  Left parietal optic radiations 
F.  Left occipital cortex 

Question 14-9:
Right homonymous inferior quadrant defect.

Answer 9

Answer 14-9: E.
Lesion of the left superior optic radiations,
beneath the parietal c~rtex, produces a right
inferior quadrant defect

Question 10

Correlate the visual field defect with 
the appropriate anatomic structure. 
A.  Left retina 
B.  Optic chiasm 
C.  Right optic nerve 
D.  Left temporal optic radiations 
E.  Left parietal optic radiations 
F.  Left occipital cortex 

Question 14-10:
Complete loss of vision in the right eye.

Answer 10

Answer 14-10:C.
Lesion of the right optic nerve results in loss
of vision of the eye without affecting vision
from the left eye, unless the lesion is near the
chiasm.