1.
Describe why pts may be mis-diagnosed with ocular HTN & LTG based on their corneas.
2.
What is the equatio for ocular perfusion (OP)?
3.
Small scleral canals tend to be related to what type of refractive error?
Correct Answer
B. Hyperopes
Explanation
Scleral canal size directly related to ONH & cup size
4.
Indicate which areas of the lamina cribosa tend to have larger pore size.
Correct Answer(s)
A. Superior
D. Inferior
Explanation
Superior & inferior LC coorespond to the arcuate bundles. Larger diameter fibers (M cells) pass through superior & inferior poles (theory that M cells are affected 1st in GLC, which is the basis of FDT technology)
5.
Where is there the greatest overlap of receptive fields?
Correct Answer
B. PM bundles
Explanation
The greatest overlap of receptive fields is found in the PM bundles. Receptive fields refer to the area in the visual field that a single neuron responds to. When receptive fields overlap, it means that multiple neurons are responding to the same area, providing a more detailed and accurate representation of that particular region. In the case of PM bundles, the overlap of receptive fields is the highest, indicating a higher level of visual acuity and sensitivity in that area.
6.
Most early VF loss in GLC occurs in the periphery and progresses centrally, eventually leading to blindness if left untreated.
Correct Answer
B. False
Explanation
Most early GLC VF loss occurs centrally, and later in the periphery
7.
Indicate all the signs/symptoms associated with DIFFUSE axon loss.
Correct Answer(s)
B. Tritan (B/Y) CV defect
D. Younger pts
Explanation
Diffuse Axon Loss:
- generalized cup increase (ROUND)
- generalized RNFL drop out
- general depression of VF
- Tritan CV defect
- increased latency & amp on ERG
- often in younger pts & higher IOPs
Focal Axon Loss:
- ONH damage in localized regions (notching, vertical cup enlargement, occasionally temporal rim)
- RNFL loss localize to arcuate bundles (slit defects, wedge defects)
- Focal VF loss; arcuates damaged most often (nasal step, paracentral scotomas)
- often in elderly, normal/slightly elevated IOPs
8.
You do not need an increase an IOP or VF loss to diagnose GLC.
Correct Answer
A. True
Explanation
GLC dx may be made of a basis of: structural damage OR functional loss OR high risk
9.
GLC functional changes can precede structural damage by years
Correct Answer
B. False
Explanation
Opposite! Structural damage can precede functional changes by years (pre-perimetric GLC)
10.
1 tonometry reading has low sensitivity and relatively high specificiy
Correct Answer
A. True
Explanation
50% sensitivity due to 1) substantial IOP variation in GLC pts, 2) varing susceptiblty of different pts to IOP-related damage
70-90% specificity --> most normals (non-GLC) show IOP < 21
11.
Which of the following GLC meds does not work at night?
Correct Answer
B. Timolol
Explanation
Beta blockers do not work at night
12.
Which ethnicity is the strongest risk factor for developing 'normal tension' GLC?
Correct Answer
C. Japanese
Explanation
Af. Am. + Hispanics --> POAG
Chiese + Viet + Eskimo --> lower risk for POAG, but higher risk for ACG
13.
Which of the following systemic disease results in slower recycling of mucopolysaccharides in the TM endothelium and subsequent increase in IOP?
Correct Answer
D. Hypothyroidism
Explanation
- Hypothyroidism --> not a vascular issue, messes with the TM
- High BP --> aggressively lowering BP is probably worse than high BP bc then you risk compromising the ON perfusion; however, long term high BP increases risk of GLC due to increased risk of arteriosclerosis & other vascular diseases
- Diabetes --> vascular compromise
14.
Corneal edema will result in false ____ IOP
Correct Answer
A. Low
Explanation
corneal edema --> false low
corneal scarring --> false high
15.
I-Care tonometry has many advantages including: no anesthetic needed, portable, less affected by biomechanical factors compared to NCT
Correct Answer
B. False
Explanation
I-Care is portable & does not require anesthetic, however it is still applanates and therefore is susceptible to IOP inaccuracies due to corneal biomech factors
16.
Thicker corneas will have a false high IOP reading on GAT.
Correct Answer
A. True
Explanation
Thin Ks --> false low
Think Ks --> false high (LASIK pts will have a false low reading due to thinner corneas)
17.
1 mmHg increase in IOP results in ___% increased risk for GLC damage
Correct Answer
B. 10%
Explanation
A 1 mmHg increase in intraocular pressure (IOP) results in a 10% increased risk for glaucoma (GLC) damage. Glaucoma is a disease that damages the optic nerve, often caused by increased pressure in the eye. Studies have shown that even a small increase in IOP can significantly increase the risk of developing glaucoma and experiencing damage to the optic nerve. Therefore, a 1 mmHg increase in IOP corresponds to a 10% increased risk for glaucoma damage.
18.
For every ____ microns thinner CCT than normal, there is a ____% increased risk for GLC damage.
Correct Answer
40
70
Explanation
For every 40 microns thinner central corneal thickness (CCT) than normal, there is a 70% increased risk for glaucoma (GLC) damage. This means that as the CCT decreases by 40 microns, the risk of GLC damage increases by 70%. This relationship suggests that thinner CCT may be a risk factor for developing glaucoma.
19.
What is the standard of care in GLC detection & management?
Correct Answer
C. W/W Automated Threshold Perimetry
Explanation
Dr. Comer indicated that pachymetry will most likely become the standard of care, but at this point (as least legally) it is W/W perimetry
20.
One advantage of FDT/Matrix perimeters is that they are better at detecting change in VFs since GLC VF loss gets 'deeper' (less sensitive) as it progresses.
Correct Answer
B. False
Explanation
This is actually a disadvantage of FDT/Matrix since these perimeters bottom-out at 0dB, whereas W/W perimeters can go into the negative numbers to show the relative change between the pt's different VF tests.
21.
What is the minimum number of VFs that should within the 1st 2 years of GLC diagnosis?
Correct Answer
C. 6
Explanation
At least 3 the 1st year & 3 the 2nd year to determine rate of progression and RO rapid progression
22.
What is the most common mode of GLC progression?
Correct Answer
A. VF defect gets denser
Explanation
Denser 79%
Increased size 53%
New VF in same hemifeld 50%
Improvement 2% (temporary)
23.
Where are paracentral scotomas most likely to appear in early GLC VF loss (in terms of VF, not retina)?
Correct Answer
D. Nasal
Explanation
Occur in nasal VF because arcuates are affected which are in the temporal retina. Can also occur beyond 20 deg superior.
24.
Nasal steps do NOT cross horizontal midline
Correct Answer
A. True
Explanation
Temporal wedge defects (nasal radial fibers) DO/CAN cross horizontal midline
25.
Which area of the ON is focal damage most likely to occur?
Correct Answer
B. Inferior
Explanation
Focal damage is most likely to occur in the inferior area of the ON.
26.
Cupping precedes pallor in GLC
Correct Answer
A. True
Explanation
Cupping w/o pallor inside cup until later is highly specific for GLC.
Pallor of the rim tissue outside cup is non-GLC optic atrophy
27.
What % of normal pts have C:D > 0.7?
Correct Answer
C. 2%
Explanation
The correct answer is 2% because it is the percentage of normal patients who have a C:D (Cup-to-Disc) ratio greater than 0.7. This means that out of all the normal patients, only 2% of them have an optic cup size that is more than 70% of the optic disc size.
28.
Zone Alpha is more peripheral than Zone Beta
Correct Answer
A. True
Explanation
Zone Beta is closer to ONH & has large chorodial vessles
Zone Alpha is more peripheral & is the irregular pigmented outer edge of Beta
29.
Parapapillary atrophy represents extensive damage to the ONH.
Correct Answer
B. False
Explanation
Parapapillary atrophy can precede GLC ONH damage by years. It is most commonly associated with age and is not a very strong sign for GLC. It is more common in DIFFUSE ONH damage & LTG. DDx RPE crescent
30.
Like many signs of GLC, drance hemes are not highly specific to GLC
Correct Answer
B. False
Explanation
Drance hemes are common, but transient. Precedes ONH damage / VF loss by years. Indicates chronic vascular insufficiency...future damage is coming
31.
____% of eyes w/ drance hemes will develop VF loss progression over the next 16 mo
Correct Answer
D. 60%
Explanation
Many eyes w/ drance hemes develop a focal notch at the location of drance heme & cooresponding VF defect
32.
Indicate ALL of the DDx's for drance hemes
Correct Answer(s)
A. DM
B. Anti-coagulant
D. Migraine
G. PVD
H. AION
Explanation
Drance hemes, also known as flame-shaped hemorrhages, are typically seen in the retina and can be indicative of various underlying conditions. The given answer options include DM (diabetes mellitus), anti-coagulant use, migraine, PVD (peripheral vascular disease), and AION (anterior ischemic optic neuropathy). These conditions are known to be associated with the development of drance hemes. However, it is important to note that this list is not exhaustive, and other conditions such as CRVO (central retinal vein occlusion) and cardiovascular disease can also cause drance hemes.
33.
It is best to look for RNFL drop out with the slit lamp under high mag so you can determine whether or not the fine striations are present or absent,
Correct Answer
B. False
Explanation
For RNFL eval, want LOW MAG or else you will likely think there is a defect when there is not. For ONH eval, you want HIGH MAG so you can see details
34.
Which of the following does NOT require treatment (assume the signs below are the only evidence you are basing you decision from).
Correct Answer
B. Slit defect in pt having their 1st comprehensive eye exam
Explanation
If you are providing care for a pt for the first time and you notice a slit defect, it would be best to monitor at this point. Since you have no idea about the change/progression of the condition, it would be too soon to treat, and it could be a pseudo-defect. If they have cooresponding ONH damage, then it would be a good idea to treat.