ROUB UPDATED SCRIPT 2026 PRACTICE
SOLUTIONS GRADED A+
● If a gain setting is increased in order to obtain a 100% tall retina and
sclera echo, what type of cataract is being evaluated ? Answer: A dense
cataract
● What transducer frequency is generally used for a biometry A-Scan
probe ? Answer: 10 MHz
● What is the velocity of a biometer that only uses an average velocity to
measure the entire axial length ? Answer: 1550 m/sec
● What is one of the most important features of a biometer ? Answer:
The display screen
● What are the velocity settings for a phakic eye ? Answer: (+) Aqueous
: 1532 m/s
(+) Crystalline Lens : 1641 m/s
(+) Vitreous : 1532 m/s
● What should the examiner do to reduce the presence of a reverberation
echo created by a dense cataract ? Answer: Reduce the gain
, ● What is the term for the electronic calipers that measure the distance
between two or more anatomic interfaces ? Answer: Gates
● Of the following settings on the biometer screen (gain, gates, A-scan
probe frequency, eye type and screen brightness), which cannot be
changed by the examiner ? Answer: A-Scan probe frequency
● What is the proper sound velocity used to measure the distance
between the anterior ans posterior lens interfaces in a phakic eye ?
Answer: 1641 m/s
● when performing immersion biometry, which gate in relation to the
initial spike represents the cornea ? Answer: Corneal gate is to the right
of the initial spike
● What is the possible cause for a biometry instrument to indicate an
unusually short measurement of a psuedophakic eye with a PMMA
implant ? Answer: Multiple signal of the echo with improper
identification of the retina
● What biometer setting changes the degree of echo amplification ?
Answer: Gain
SOLUTIONS GRADED A+
● If a gain setting is increased in order to obtain a 100% tall retina and
sclera echo, what type of cataract is being evaluated ? Answer: A dense
cataract
● What transducer frequency is generally used for a biometry A-Scan
probe ? Answer: 10 MHz
● What is the velocity of a biometer that only uses an average velocity to
measure the entire axial length ? Answer: 1550 m/sec
● What is one of the most important features of a biometer ? Answer:
The display screen
● What are the velocity settings for a phakic eye ? Answer: (+) Aqueous
: 1532 m/s
(+) Crystalline Lens : 1641 m/s
(+) Vitreous : 1532 m/s
● What should the examiner do to reduce the presence of a reverberation
echo created by a dense cataract ? Answer: Reduce the gain
, ● What is the term for the electronic calipers that measure the distance
between two or more anatomic interfaces ? Answer: Gates
● Of the following settings on the biometer screen (gain, gates, A-scan
probe frequency, eye type and screen brightness), which cannot be
changed by the examiner ? Answer: A-Scan probe frequency
● What is the proper sound velocity used to measure the distance
between the anterior ans posterior lens interfaces in a phakic eye ?
Answer: 1641 m/s
● when performing immersion biometry, which gate in relation to the
initial spike represents the cornea ? Answer: Corneal gate is to the right
of the initial spike
● What is the possible cause for a biometry instrument to indicate an
unusually short measurement of a psuedophakic eye with a PMMA
implant ? Answer: Multiple signal of the echo with improper
identification of the retina
● What biometer setting changes the degree of echo amplification ?
Answer: Gain
