ROUB UPDATED QUESTIONS AND ANSWERS GRADED
A+
✔✔What mode should be used in an intraocular abnormality in known or suspected? -
✔✔Manual mode
✔✔Ideally, what should be displayed on the A-scan machine's monitor? - ✔✔Numerical
axial length measurement, anterior chamber depth, lens thickness, and vitreous length
✔✔How frequently should the probe tip be cleaned? - ✔✔Between each patient
✔✔Where are posterior chamber lenses typically placed? - ✔✔In the capsular bag
✔✔Where are iris-plane (iris-supported) lenses fixated? - ✔✔In the region of the pupil
✔✔What type of power will an IOL yield if the eye is short? - ✔✔Higher power
✔✔What type of power will an IOL yield if the eye is long? - ✔✔Lower power
✔✔What type of lens implant will give a patient vision for both reading and distance
vision? - ✔✔Multifocal implant
✔✔What type of IOL has a higher refractive index than silicone and
Polymethylmethacrylate (PMMA)? - ✔✔Acrylic IOLs
✔✔What lens power is required for posteriorly-positioned implants? - ✔✔Higher
✔✔What requirements are necessary when personalizing IOL constants? - ✔✔The
same biometry and keratometry equipment, techniques, and examiners
✔✔What is the result of a high diopter implant power? - ✔✔The greater the center
thickness for a given index of refraction
✔✔What is the range of implant thickness? - ✔✔0.4 mm to 1.5 mm
✔✔What is the range in diameters for the optics of IOLs? - ✔✔5.0 mm to 7.0 mm
✔✔What is the formula used to determine the true axial length measurement using the
velocity conversion equation? - ✔✔TAL = Vc (Correct Sound Velocity)/Vm (Incorrect
Sound Velocity) x AAL
✔✔What formula is used to provide the correction of an erroneous measurement from
the use of an incorrect sound velocity setting? - ✔✔Velocity conversion equation
, ✔✔What is the correction factor of a pseudophakic eye with a PMMA IOL? - ✔✔+0.4
mm
✔✔What is the correction factor for a silicone IOL? - ✔✔-0.8 mm
✔✔What is the correction factor for a pseudophakic eye with an acrylic IOL? - ✔✔+0.2
mm
✔✔What is defined when an implant is situated in the sulcus? - ✔✔The lens is placed
between the iris base and the ciliary body
✔✔What is a multi-piece lens implant? - ✔✔A lens implant comprised of different
materials (the haptics are different from the optics)
✔✔What IOLs are typically fixated by the anterior chamber angle? - ✔✔Anterior
chamber lens implant
✔✔What four pieces of information are needed to perform IOL power calculations? -
✔✔Axial length measurement, average K reading, A-constant, and desired post
operative refraction
✔✔What formula is used to determine true axial length (TAL) for a PMMA IOL? -
✔✔TAL = AAL (Apparent Axial Length) + 0.44 x T (Center Thickness)
✔✔What empirical formula is based on retrospective analysis of actual post operative
refraction data? - ✔✔Regression formula
✔✔What are the two components of an intraocular lens? - ✔✔Optic and haptic
✔✔What are the three primary locations for IOL placement? - ✔✔Anterior chamber, iris
plane, and posterior chamber
✔✔What are the basic styles of optics (IOLs)? - ✔✔Forward meniscus
(convexoconcave), convexplano, biconvex (steep front), equiconvex, biconvex (steep
back), planoconvex, and reverse meniscus (concavoconvex)
✔✔Which primary location in the eye would the highest powered IOL be located? -
✔✔The posterior chamber
✔✔In a planned monofocal IOL placement in both eyes, what is the dioptric difference
between them? - ✔✔1 diopter
A+
✔✔What mode should be used in an intraocular abnormality in known or suspected? -
✔✔Manual mode
✔✔Ideally, what should be displayed on the A-scan machine's monitor? - ✔✔Numerical
axial length measurement, anterior chamber depth, lens thickness, and vitreous length
✔✔How frequently should the probe tip be cleaned? - ✔✔Between each patient
✔✔Where are posterior chamber lenses typically placed? - ✔✔In the capsular bag
✔✔Where are iris-plane (iris-supported) lenses fixated? - ✔✔In the region of the pupil
✔✔What type of power will an IOL yield if the eye is short? - ✔✔Higher power
✔✔What type of power will an IOL yield if the eye is long? - ✔✔Lower power
✔✔What type of lens implant will give a patient vision for both reading and distance
vision? - ✔✔Multifocal implant
✔✔What type of IOL has a higher refractive index than silicone and
Polymethylmethacrylate (PMMA)? - ✔✔Acrylic IOLs
✔✔What lens power is required for posteriorly-positioned implants? - ✔✔Higher
✔✔What requirements are necessary when personalizing IOL constants? - ✔✔The
same biometry and keratometry equipment, techniques, and examiners
✔✔What is the result of a high diopter implant power? - ✔✔The greater the center
thickness for a given index of refraction
✔✔What is the range of implant thickness? - ✔✔0.4 mm to 1.5 mm
✔✔What is the range in diameters for the optics of IOLs? - ✔✔5.0 mm to 7.0 mm
✔✔What is the formula used to determine the true axial length measurement using the
velocity conversion equation? - ✔✔TAL = Vc (Correct Sound Velocity)/Vm (Incorrect
Sound Velocity) x AAL
✔✔What formula is used to provide the correction of an erroneous measurement from
the use of an incorrect sound velocity setting? - ✔✔Velocity conversion equation
, ✔✔What is the correction factor of a pseudophakic eye with a PMMA IOL? - ✔✔+0.4
mm
✔✔What is the correction factor for a silicone IOL? - ✔✔-0.8 mm
✔✔What is the correction factor for a pseudophakic eye with an acrylic IOL? - ✔✔+0.2
mm
✔✔What is defined when an implant is situated in the sulcus? - ✔✔The lens is placed
between the iris base and the ciliary body
✔✔What is a multi-piece lens implant? - ✔✔A lens implant comprised of different
materials (the haptics are different from the optics)
✔✔What IOLs are typically fixated by the anterior chamber angle? - ✔✔Anterior
chamber lens implant
✔✔What four pieces of information are needed to perform IOL power calculations? -
✔✔Axial length measurement, average K reading, A-constant, and desired post
operative refraction
✔✔What formula is used to determine true axial length (TAL) for a PMMA IOL? -
✔✔TAL = AAL (Apparent Axial Length) + 0.44 x T (Center Thickness)
✔✔What empirical formula is based on retrospective analysis of actual post operative
refraction data? - ✔✔Regression formula
✔✔What are the two components of an intraocular lens? - ✔✔Optic and haptic
✔✔What are the three primary locations for IOL placement? - ✔✔Anterior chamber, iris
plane, and posterior chamber
✔✔What are the basic styles of optics (IOLs)? - ✔✔Forward meniscus
(convexoconcave), convexplano, biconvex (steep front), equiconvex, biconvex (steep
back), planoconvex, and reverse meniscus (concavoconvex)
✔✔Which primary location in the eye would the highest powered IOL be located? -
✔✔The posterior chamber
✔✔In a planned monofocal IOL placement in both eyes, what is the dioptric difference
between them? - ✔✔1 diopter
