OPT 210 TONOMETRY EXAM QUESTIONS AND CORRECT ANSWERS
100% CORRECT!!
What is the average rate of production for aqueous solution?
2-2.5 uL/minute
What are the 3 functions of aqueous?
-transport nutrients
-provide internal pressure
-refractive media (clear when healthy, protein free)
What nutrients are transported in aqueous?
-ascorbate
-hydrogen
-chloride ions
What is the conventional pathway of aqueous outflow (80-95%)?
Corneoscleral trabecular meshwork →
juxtacanalicular connective tissue TM →
*Schlemms canal →
*collector channels →
aqueous veins →
episcleral veins
*sources of resistance
,What is the unconventional pathway of aqueous outflow (5-35%)?
Uveal meshwork →ciliary muscle →supraciliary and suprachoroidal spaces→uveoscleral
outflow across sclera →orbital vasculature, vortex veins, CB lymphatic vessels
What is intraocular pressure?
balance between amount of aqueous humor produced vs drained
What are the units of IOP?
mmHg
What is the goldmann equation?
IOP = (Rate of aqueous formation/ease of aqueous outflow) + episcleral venous pressure
What is tonometry?
method of measuring IOP (transcorneal pressure=estimation)
What is the modern understanding of concern regarding elevated IOP measurements?
IOP at which optic nerve sustains damage (since normal IOP can vary for every patient)
historically, elevated IOP was considered to be over 21 mmHg
What are risk factors for glaucoma?
-corneal thickness and hysteresis
-IOP, episcleral venous pressure, ocular perfusion pressure, cerebrospinal fluid
pressure
-age
, -family history
What is the average IOP?
15.5 mmHg
What is the daily fluctuation of IOP?
2-6 mmHg
What is considered to be asymmetry in terms of IOP?
≥ 3mmHg between eyes
What is classified as ocular hypertension?
>24 mmHg
-no signs of glaucomatous damage
T or F: higher IOP and thinner corneal thickness increases risk of glaucoma.
True
What is hypotony?
low IOP that usually occurs after ocular inflammation, trauma, or surgery; 6.5 mmHg
-decreased IOP due to lack of globe integrity (penetrating trauma, wound leak, post
surgical)
100% CORRECT!!
What is the average rate of production for aqueous solution?
2-2.5 uL/minute
What are the 3 functions of aqueous?
-transport nutrients
-provide internal pressure
-refractive media (clear when healthy, protein free)
What nutrients are transported in aqueous?
-ascorbate
-hydrogen
-chloride ions
What is the conventional pathway of aqueous outflow (80-95%)?
Corneoscleral trabecular meshwork →
juxtacanalicular connective tissue TM →
*Schlemms canal →
*collector channels →
aqueous veins →
episcleral veins
*sources of resistance
,What is the unconventional pathway of aqueous outflow (5-35%)?
Uveal meshwork →ciliary muscle →supraciliary and suprachoroidal spaces→uveoscleral
outflow across sclera →orbital vasculature, vortex veins, CB lymphatic vessels
What is intraocular pressure?
balance between amount of aqueous humor produced vs drained
What are the units of IOP?
mmHg
What is the goldmann equation?
IOP = (Rate of aqueous formation/ease of aqueous outflow) + episcleral venous pressure
What is tonometry?
method of measuring IOP (transcorneal pressure=estimation)
What is the modern understanding of concern regarding elevated IOP measurements?
IOP at which optic nerve sustains damage (since normal IOP can vary for every patient)
historically, elevated IOP was considered to be over 21 mmHg
What are risk factors for glaucoma?
-corneal thickness and hysteresis
-IOP, episcleral venous pressure, ocular perfusion pressure, cerebrospinal fluid
pressure
-age
, -family history
What is the average IOP?
15.5 mmHg
What is the daily fluctuation of IOP?
2-6 mmHg
What is considered to be asymmetry in terms of IOP?
≥ 3mmHg between eyes
What is classified as ocular hypertension?
>24 mmHg
-no signs of glaucomatous damage
T or F: higher IOP and thinner corneal thickness increases risk of glaucoma.
True
What is hypotony?
low IOP that usually occurs after ocular inflammation, trauma, or surgery; 6.5 mmHg
-decreased IOP due to lack of globe integrity (penetrating trauma, wound leak, post
surgical)
