Ortho-K Practice Test

These questions are part of the practice quiz. Start practicing

• How should corneal staining or irritation be managed in a patient using ortho-k lenses?
• Which of the following is a cause of poor VA after ortho-K fitting?
• Lateral decentration is caused by an incorrect ______ and is solved by increasing ______ or ______.
• Which statement about ortho-K is accurate?
• Ortho-K is a (permanent/temporary) resolution of myopic prescription.
• Which equipment is essential to verify ortho-k fit and corneal changes?
• What percentage decrease in elongation was observed with Ortho-K compared to specs?
• Superior decentration is caused by being too which?
• What is the main objective of fluorescein evaluation during ortho-k lens fitting?
• What effect does ortho-K have on myopia?
• The landing zone angle can influence which of the following?
• The Landing Zone controls edge lift and centration.
• What factors make ortho-k a suitable option for pediatric patients in myopia control?
• Which statement best describes tear exchange in ortho-k optimization?
• Which scenario would prompt re-evaluation of lens design or fit?
• Which map type is preferred for assessing curvature changes and predicting lens position for overnight wear?
• Which of the following is NOT listed as a sign of misfit for an ortho-k lens?
• What is a reverse-geometry lens and why is it used in ortho-k?
• Ortho-K uses what Dk material?
• Which factors influence how much astigmatism can be corrected with ortho-k lenses?
• In orthokeratology, BC (back vertex curve) is typically modified under which circumstance?
• How does orthokeratology influence peripheral defocus and why is this relevant to myopia control?
• What is a possible development after stabilization if ortho-k wear is continued?
• Which of the following is NOT an indication for ortho-K?
• What role does epithelial remodeling play in ortho-k?
• Does ortho-K stop myopia progression?
• How does corneal thinning influence ortho-k eligibility?
• Which condition is listed as a contraindication for ortho-K?
• What refractive error range is typically considered suitable for ortho-k in adults?
• During dispensing, which assessment is used to evaluate lens fit?
• Return zone diameter is more prominent with higher myopic correction.
• What is the primary mechanism by which ortho-k reduces myopic refractive error?
• Which elements should be included in patient education during initial ortho-k counseling?
• Glare/halos with ortho-K are common and tend to be worse at night.
• Is a plunger a possible way to remove ortho-K lenses?
• If symptoms persist after management of corneal staining or irritation, what is advised?
• What type of lens is used in ortho-k?
• Which of the following is a complication of ortho-K fitting?
• Where should bearing be seen in ortho K fits?
• Topography shows lens position most clearly under which condition?
• Solution to inferior decentration is to adjust which combination?
• Which of the following is a cause of poor VA after ortho-K fitting?
• How does ortho-k primarily affect daytime refractive power after overnight wear?
• Which imaging modality is used to map anterior curvature changes in ortho-k patients?
• Sagittal height greater than 30 μm indicates which landing zone?
• Myopia progression is considered a good candidate criterion for ortho-K.
• What are common categories of orthokeratology fit outcomes and how are they addressed?
• Ortho-K lens material uses which Dk value?
• The measure of the cornea's ability to return to its original position after deformation is called?
• What is the typical magnitude range of the Jessen factor?
• Back zone diameter (return zone) adjustments are made in increments of how many micrometers?
• Insertion bubbles can be removed by instilling what into the bowl before placing on the eye?
• Which of the following is a complication of ortho-K fitting?
• Ortho-K decreased elongation by __% compared to specs.
• What does a sagittal height greater than 30 μm indicate?
• Which of the following is a good candidate characteristic?
• Which two zones are described as determining sagittal depth/centration and edge lift/centration, respectively?
• What does Dk indicate in ortho-K lens materials?
• Tangential maps show the rate of curvature change and give an idea of what?
• Which step is part of the dispensing protocol for ortho-K lenses?
• Which of the following is NOT a factor causing variable VA after ortho-K?
• Name two absolute contraindications for ortho-k beyond infection and keratoconus.
• Key hygiene principles for ortho-k lens care?
• Inferior decentration is seen as which pattern?
• What are two common reasons for less-than-expected ortho-k results?
• Which statement about landing zone angle is true?
• What is peripheral corneal steepening and why is it important in ortho-k?
• Which of the following is a complication of ortho-K fitting?
• How many hours per night should ortho-K lenses be worn?
• The Return Zone determines sagittal depth and centration.
• With orthokeratology, which pattern is observed: central flattening and midperipheral steepening?
• What is the standard width of the BC in a standard ortho-k lens?
• Degree of landing zone angle equals __um change in sagittal depth?
• Which lens-design parameters primarily determine the amount of central flattening achieved by ortho-k?
• Which of the following is true about toric design in the context of correcting decentration?
• Which type of topography map should be used?
• Which of the following is listed as a good candidate consideration?
• Which of the following contributes to variable VA after ortho-K?
• Which measurement confirms central corneal thickness and helps screen for keratoconus risk?
• Why document lens power changes at each follow-up?
• In the context of inferior decentration, what is the recommended adjustment to LZA?
• How does ortho-k typically affect daytime uncorrected visual acuity?
• Which of the following contributes to variable VA after ortho-K?
• Ortho-K aims to preserve central vision while creating what in the peripheral retina?
• Which topic is included in patient education during the dispensing visit?
• What key points should be covered with the patient regarding lens case hygiene for ortho-k?
• If the back surface curvature is incorrect, which outcome is most likely?
• What does the Jessen factor represent?
• Which combination of factors can cause a lens to be too flat?
• What type of lens material is primarily used in ortho-k and why?
• Which statement about the peripheral defocus strategy in ortho-K is correct?
• What is the stated long-term advantage of ortho-k compared with glasses?
• How many days does ortho-K treatment typically take to start working?
• How is transient corneal edema related to overnight ortho-k wear, and how is it managed?
• The Jessen factor addresses which daily phenomenon after lens wear?
• What ethical considerations should guide ortho-k practice?
• How do ortho-k and refractive surgery compare in terms of reversibility?
• How is BC calculated?
• Which statement best describes a central island correction?
• Which of the following describes reverse curve design possibilities?
• Where should you see clearance in ortho K fits?
• Which parameter is used to monitor corneal safety during ortho-k?
• If corneal thickness is thinner than expected, what risk becomes more relevant for ortho-k candidacy?
• What does the term 'vault' mean in ortho-k lens fitting?
• Which statement best describes why BC may be modified during fitting?
• What information does an over-refraction provide in ortho-k fitting?
• What corneal change pattern is achieved by ortho-k?
• What is central island formation in ortho-k and what does it indicate?
• What is the recommended approach if daytime fogging or glare occurs after ortho-k?
• Which of the following is listed as a complication of ortho-K fitting?
• When did FDA approve ortho-K for up to -6D myopia reduction?
• Which parameter is used to assess the cornea's viscoelastic response to deformation?
• Should you see central bearing with ortho-K fits?
• Which pattern describes central flattening and midperipheral steepening in ortho-K?
• Why is it important to monitor lens fit and corneal response during ortho-k treatment?
• Which factor is essential for ortho-k success, enabling lens movement and stable corneal changes?
• Bearing can be observed in which region(s) for ortho-K fits?
• What is the typical first follow-up timing after initial ortho-k lens fitting?
• The reverse curve design in ortho-k can be toric or dual axis.
• Who proposed ortho-focus using flatter than K to flatten the cornea with myopic tear film?
• What ongoing process during epithelial remodeling affects the stability of ortho-k outcomes?
• Which of the following pairs correctly matches a person with their ortho-K contribution?
• Is orthokeratology an option for keratoconus?
• What is the main goal of ortho-k lens wear overnight?
• What is the minimum number of topography images required per eye?
• Which assessment is used to monitor corneal shaping and lens fit during ortho-k follow-up?
• True or False: The BC is not changed for the fit of the ortho-K lens.
• Which of the following contributes to variable VA after ortho-K?
• Hydrostatic forces redistribute which substance in the corneal epithelium to compress the central cornea and thicken the mid peripheral cornea?
• Why is ocular surface health and corneal nerve integrity considered when selecting ortho-k candidates?
• What is the general purpose of ortho-K?
• Which of the following is a cause of poor VA after ortho-K fitting?
• Which finding is most indicative of misfit during evaluation of an ortho-k lens?
• The landing zone angle allows for which three factors?
• Which of the following is listed as a good candidate consideration for ortho-K?
• Can ortho-k correct astigmatism, and to what extent?
• Which condition would prompt reconsideration or stopping ortho-k treatment?
• Which outcome might occur after ortho-K lenses compared to glasses?
• Which item is included in the ortho-K workup as part of a standard exam?
• What is the typical maximum nightly wear duration recommended for ortho-k lenses?
• Which assessment best monitors the ongoing success of ortho-k reshaping during follow-up?
• Ortho-k achieves refractive change primarily through what process on the cornea?
• Which chord length is used for sagittal height measurement on topography?
• Why is lens centration important for ortho-k outcomes?
• What central corneal change is expected after ortho-K treatment?
• What effect does peripheral myopic defocus produced by ortho-k have on axial elongation?
• After six months, you should repeat which measurement?
• Superior decentration is typically visualized on topo images or fluorescein staining as which pattern?
• Decreasing LZA in the context of decentration has what effect?
• Which of the following is a RTC follow-up time after ortho-K dispensing?
• Which condition would prompt reconsideration or stopping ortho-k treatment?
• To resolve a central island, which adjustments should be made?
• In ortho-K, glare is worse at which time of day?
• In topography, sagittal height on an 8 mm chord length greater than how many micrometers indicates a toric landing zone?
• OAD determination of ortho-K is found by taking HVID and doing what?
• Which parameter is specifically monitored to assess corneal safety during ortho-k?
• What is the purpose of corneal topography in the ortho-k fitting process?
• Central corneal thickness threshold commonly used for screening eligibility for ortho-k?
• Which imaging modality may be used to assess corneal changes in ortho-k beyond topography and slit-lamp?
• To correct superior decentration by steepening the lens, which combination is used?
• What material property is most critical for ortho-k lenses worn overnight?
• Which pairing correctly describes treatment zone effects?
• Name a sign that requires re-fitting after ortho-k lens wear.
• In ortho-K, myopic defocus is created in the mid-periphery. What type of defocus is produced there?
• Why are regular follow-up visits important after ortho-k fitting?
• Which measurement should be repeated at six months?
• Why is ortho-k an attractive option for pediatric patients with myopia progression?
• True or False: Insertion bubbles can be removed by changing RZD and LZA appropriately.
• Reverse geometry curves use which force to flatten the central cornea?
• What is the typical approach to lens wear timing for ortho-k?
• Which practice can improve topography image quality?
• Is lower corneal eccentricity harder to treat in orthokeratology?
• Who first fit glass scleral lenses on keratoconus patients?
• Why is proper centration of the ortho-k lens important?
• Which corneal parameter is most important to assess when considering ortho-k candidacy?
• Which factors cause landing too soon?
• A central island is caused by which condition?
• Which statement is true regarding corneal hysteresis and return to baseline?
• What is a typical follow-up plan after the initial month of ortho-k treatment?
• What is essential to include in patient education for ortho-k wearers?
• How long does most flattening typically take to stabilize after starting ortho-k treatment?
• OZD standard sizes for ortho Ks typically is ___ to __ mm?
• Is orthokeratology recommended for keratoconus?
• Which option is NOT a recommended adjustment for superior decentration?
• What is the pediatric benefit of ortho-k beyond slowing progression?
• ________ is critical for a proper ortho K fit?
• Which item is used specifically to map the cornea during the ortho-K workup?
• The component that controls refractive power.
• Inferior decentration is typically caused by which two factors?
• Over what timeframe does ortho-k typically achieve stable daytime vision after reshaping?
• Which of the following is a cause of poor VA after ortho-K fitting?
• How can ortho-K lenses be removed?
• Which statement best describes the overall effect of ortho-K on refractive error?
• What role does tear film quality play in ortho-k success?
• Which of the following is a good candidate criterion for ortho-K?