CDOS Practice Questions And Correct Answers
(Verified Answers) 2026
What condition can be imaged with UBM and is described as a blunting or
rounding of the angle?
Angle Recession
What is a disadvantage to 20 MHz B-Scan over UBM?
Resolution is much lower than UBM
What is the BEST description of the movement of a PVD on B-Scan?
Highly mobile
What is the name of the condition that is described as an outpouching of the
posterior aspect of the globe on B-Scan?
Staphyoma
What property of silicone oil is responsible for the artefactually large images with
B-Scan?
Velocity
What structure imaged with UBM looks like a tiny tornado?
IOL haptic
When performing a UBM for suspected iridociliary cysts in the study eye, why
would you scan both eyes?
Cysts are highly likely in the other eye id there is more than 1 in the study eye
What statement is TRUE regarding standardized A-Scan?
Thyroid eye disease can be detected and followed
Ringing artefacts along the optic nerve shadow are suggestive of:
Fluid around the optic nerve
, Which statement about B-Scan is TRUE?
Differentiating between vitreous hemorrhage and inflammation is not possible
without a history
On a routine UBM exam you note an area of reverberation echoes near the sulcus
that look like a small tornado. What is a possible explanation?
IOL Haptic
What examination protocol would you follow if a patient was referred because of a
history of trauma and a cataract?
Zonules Exam
What examination protocol would you follow if a patient was referred for narrow
angle glaucoma?
Angles Exam
What examination protocol would you follow if a patient was referred for a
pigmented iris lesion?
Iris lesion Exam
What examination protocol would you follow if a patient was referred for an
elevated area noted on slit lamp exam?
Iridociliary cyst Exam
On a routine UBM exam you note the angle appears rounded from 4oc-8oc. What
is a possible explanation?
Angle Recession
Sound Velocities:
Air/Gas: 340 m/s
Oil= 980 m/s
Water= 1480 m/s
Aqueous= 1532 m/s
Vitreous= 1532 m/s
Soft Tissue= 1550 m/s
(Verified Answers) 2026
What condition can be imaged with UBM and is described as a blunting or
rounding of the angle?
Angle Recession
What is a disadvantage to 20 MHz B-Scan over UBM?
Resolution is much lower than UBM
What is the BEST description of the movement of a PVD on B-Scan?
Highly mobile
What is the name of the condition that is described as an outpouching of the
posterior aspect of the globe on B-Scan?
Staphyoma
What property of silicone oil is responsible for the artefactually large images with
B-Scan?
Velocity
What structure imaged with UBM looks like a tiny tornado?
IOL haptic
When performing a UBM for suspected iridociliary cysts in the study eye, why
would you scan both eyes?
Cysts are highly likely in the other eye id there is more than 1 in the study eye
What statement is TRUE regarding standardized A-Scan?
Thyroid eye disease can be detected and followed
Ringing artefacts along the optic nerve shadow are suggestive of:
Fluid around the optic nerve
, Which statement about B-Scan is TRUE?
Differentiating between vitreous hemorrhage and inflammation is not possible
without a history
On a routine UBM exam you note an area of reverberation echoes near the sulcus
that look like a small tornado. What is a possible explanation?
IOL Haptic
What examination protocol would you follow if a patient was referred because of a
history of trauma and a cataract?
Zonules Exam
What examination protocol would you follow if a patient was referred for narrow
angle glaucoma?
Angles Exam
What examination protocol would you follow if a patient was referred for a
pigmented iris lesion?
Iris lesion Exam
What examination protocol would you follow if a patient was referred for an
elevated area noted on slit lamp exam?
Iridociliary cyst Exam
On a routine UBM exam you note the angle appears rounded from 4oc-8oc. What
is a possible explanation?
Angle Recession
Sound Velocities:
Air/Gas: 340 m/s
Oil= 980 m/s
Water= 1480 m/s
Aqueous= 1532 m/s
Vitreous= 1532 m/s
Soft Tissue= 1550 m/s
