Glaucoma (M3) Flashcards
What are the major players in the presence of glaucoma?
- optic nerve head
- retinal nerve fiber layer
- IOP
- visual field testing
- anterior chamber angle
- central corneal thickness
What is the distance between the cup and the disc margin called?
neuroretinal rim
What is the rule as far as thickness associated with the neuroretinal rim?
ISNT from thickest to thinnest
What is the normal disc size in microns? 1. What is considered large? 2
- 1500
2. >2100
What is chorioretinal atrophy surrounding the optic nerve head called?
parapapillary changes
What are the two zones associated with parapapillary changes (and what do they surround)?
- beta (surrounds optic nerve)
2. alpha (surrounds beta zone)
What are the different disc changes associated with glaucoma?
- baring of BVs
- bayoneting
- laminar dots
- disc hemorrhage
- collaterals
What is the baring of blood vessels an early sign of?
superior or inferior rim thinning
What is a double angulation of a blood vessel called?
bayoneting
What is lamina cribosa exposure due to neuroretinal tissue loss called? 1. When is it seen? 2
- laminar dots
2. glaucoma and high myopes
What are the different types of disc hemorrhages associated with glaucoma?
- drance
2. splinter
What are connections between two veins at the disc called?
collaterals
Are changes seen in the disc or the retinal nerve fiber layer first?
RNFL
What are the instruments to detect RNFL defects?
- GDx
- HRT
- OCT
For the GDx testing, what is a quality level that is reliable?
> =8
For GDx testing, what is the numerical scale for determining asymmetry?
0-1 ; where 1 is exactly symmetric
For GDx testing, what are the associated NFI numerical values for each level: 1. low; 2. suspect; 3. high
- 0-30
- 31-50
- 51-100
For GDx testing, while looking at the nerve fiber thickness map what colors indicate thinning? 1. Thicker? 2
- blue
2. yellow and red
For GDx testing, while looking at the deviation map what colors indicate thinning? 1. Thicker? 2
- yellow and red
2. blue
For GDx testing, what does the TSNIT graph show?
patients retinal thickness compared to database average
When is GDx and OCT testing not good for glaucoma analysis?
significant parapapillary atrophy
For Stratus OCT testing, what does the RNFL quadrant show?
Sectioned off retina with green to red pies of circle filled in to represent areas of thinning
What is the test analysis that combines the colors of stratus OCT and the database of GDx?
Sirus OCT
What value is desired for HRT symmetry?
0
For HRT testing, what color represents sloping in the topography map of the ONH?
blue
Which test is best for patients with significant parapapillary atrophy?
HRT
What is the normal range of IOPs?
11-21
Is the IOP higher or lower in the morning? 1. What is this called? 2
- higher (~5)
2. diurnal curve
Do steroids increase or decrease IOP?
increase
If a patient is able to see a dimer light, will the Db level be higher or lower?
higher
What is total vision loss seen with a visual field called? 1. partial loss? 2
- absolute scotoma
2. relative scotoma
For visual field test type 30-, how many spots are there? 1. How many degrees in nasal? 2. How many degrees out temporal? 3. What type of patients generally do this test? 4
- 72
- 30 deg
- 30 deg
- neural defects
For visual field test type 24-, how many spots are there? 1. How many degrees in nasal? 2. How many degrees out temporal? 3. What type of patients generally do this test? 4
- 56
- 30 deg
- 24 deg
- glaucoma patients
What number is associated with spots tested next to the crosshairs for visual field tests? 1. On the crosshairs? 2. Which test is more common for glaucoma testing? 3
- -2
- -1
- -2
What are the different display types for threshold visual field testing analysis?
- numerical
- greyscale
- total deviation
- pattern deviation
- probability values
What are the different reliability types for threshold visual field testing analysis?
- fixation losses
- false positives
- false negatives
Which display type for threshold visual field testing analysis gives threshold (dB) values for points tested?
numerical
Which display type for threshold visual field testing analysis gives sensitivity with tones of grey?
greyscale
Which display type for threshold visual field testing analysis gives deviation from age matched normals? 1. Are high or low numbers desired? 2
- total deviation
2. low (0)
Which display type for threshold visual field testing analysis gives deviation from age matched normals and adjusts for reductions due to lens opacities or miosis?
pattern deviation
Which display type for threshold visual field testing analysis gives percent of age population with that visual field defect?
probability values
Which reliability index tracts that steadiness of gaze of the patient?
fixation loses
Which reliability index show when the patient report seeing stimulus without it being presented?
false positive
Which reliability index shows when the patient does not respond after a stimulus is presented above threshold?
false negative
What visual field global index is a measure of overall field loss?
mean deviation (MD)
What visual field global index shows focal loss or variability in a field?
pattern standard deviation (PSD)
What visual field global index detects glaucomatous visual field loss?
glaucoma hemifield test (GHT)
What visual field global index is affected by cataracts or refractive error?
mean deviation (MD)
What is an overall decrease in visual field sensitivity called?
diffuse depression
What can cause a diffuse depression visual field?
- loss of RNFL
- cataract
- small pupil
- uncorrected refractive error
What are the hallmarks of a paracentral threshold visual field defect? 1. Where are they located? 2. What is the optic nerve presentation? 3. What kind of glaucoma is it associated with? 4. How common is it? 5
- small and relatively steep
- supero-nasal
- partial focal notch (not extending to the disc)
- normal tension glaucoma
- in 70% of all early changes
Where is a nasal step threshold visual field defect most commonly seen? 1. What percentage of defects have this? 2. What is the optic nerve presentation? 3
- inferior or superior
- 7%
- wide spread fiber loss
What are the hallmarks of an arcuate threshold visual field defect? 1. What is the optic nerve presentation? 2
- coalescence of paracentral defects and arc around fixation that eventually connect to blind spot
- focal notch extending to edge of disc
What are the locations of aqueous outflow in the anterior chamber (and what percentage of outflow does each do)?
- trabecular meshwork (90%)
2. uveoscleral (10%)
Whats the most posterior structure of the anterior chamber angle? 1. Most anterior? 2
- ciliary body
2. schwalbe line
What is the order of structures seen while performing anterior chamber angle assessment (gonio)?
- iris
- ciliary body
- scleral spur
- pigmented TM
- nonpigmented TM
- Schwalbe line
What corneal thickness is Goldmann tonometry calibrated to?
520 um
What did the OHTS show proof of regarding glaucoma?
- thicker cornea (>555um) lower risk of glaucoma
2. thinner cornea (
What is the relative thickness of cornea for african americans?
thinner
What are ocular risk factors for glaucoma?
- Large C/D ratio
- increased IOP
- Parapapillary changes
- thing corneal thickness
When should an ocular hypertension patient be treated with glaucoma meds?
- IOP>30
- retinal nerve fiber loss
- parapapillary changes
- vertical C/D > 0.4
- thin corneas
What is the maximum number of glaucoma medications that a person is allowed to take at one time?
three
What are the systemic associations for normal tension glaucoma?
- hypertension
- coronary artery disease
- diabetes mellitus
- migraines
- nocturnal hypotension
What must be ruled our for diagnosis of normal tension glaucoma?
- optic nerve lesions
2. ischemic optic neuropathies
What are the risk factors for angle closure glaucoma?
- shallow anterior chamber
- shorter axial length
- small corneal dimensions
What drugs used in the treatment of acute angle closure glaucoma results in large changes in IOP?
oral osmotic
What drugs used in the treatment of acute angle closure glaucoma helps with nausea and vomitting?
antemetics
What drugs used in the treatment of acute angle closure glaucoma decrease aqueous production?
- oral acetazolamide (carbonic anhydrase inhibitor)
2. beta blocker
What drugs used in the treatment of acute angle closure glaucoma results in a constricted pupil and can only be given if IOP
topical pilocarpine
What is it called when the ciliary body is positioned anteriorly?
plateau iris
What percentage of glaucomas are secondary?
33%
Where is the pigment during pigment dispersion that forms a Krukenburg spindle?
cornea
Where is the pigment during pigment dispersion that forms a Zentmeyer’s line?
lens
Where is the pigment during pigment dispersion that forms a Sampaolesi line?
Schwalbe’s line
What are possible stimuli for the BV’s from hypoxia in neovascular glaucoma?
- central retinal vein occlusion
2. DM with proliferative retinopathy
What are the signs of rubeosis iridis?
- capillary tuffs
2. radial blood vessel growth
When can you not perform a trabeculoplasty?
when cannot see TM
What are the associated IOPs for the three stages of steroid induced glaucoma?
- low: 15 inc
What is the procedure that makes a hole in the iris either superior or temporal?
peripheral iridotomy
What is the non-permanent laser that burns 180 deg of the TM to increase outflow? 1. What is the increase in outflow amount? 2
- Argon laser trabeculoplasty
2. 50%
What is the long term efficacy laser that uses less energy?
Selective laser trabeculoplasty
What is removed during a trabeculectomy?
- portion of cornea/sclera
2. portion of iris
What is performed when there is significant scarring or other surgeries have failed to slow the glaucoma?
tube shunt
What glaucoma surgery is performed as a last resort surgical option involving freezing? 1. What is done during it (with its result)? 2. What are the complications? 3
- cyclocyrocoagulation
- ciliary body frozen (stops aqueous production)
- severe pain, hyptony
What laser glaucoma surgery is performed as a last resort surgical option? 1. What types of lasers are used? 2. What are the complications? 3
- cyclophotocoagulation
- Argon (ECP) or YAG
- inflammation, pain with injection, hyptony
What type of glaucoma is associated with sleep apnea?
normal tension glaucoma
How much RNFL loss must there be to see a visual field loss?
30-50%