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Miscellaneous Fitting Questions

Miscellaneous fitting questions from fitters and replies by Paul Rose

last updated 2020.12.29


Q: What is your opinion of piggy back, like Rose K with a daily underneath?

A: This certainly can be successful for some cases where the patient cannot tolerate the lens directly onto the cornea. However Rose K2 XL is also an option as this is often tolerated extremely well by patients who cannot wear corneal lenses. Because it involves one lens instead of two, the majority of patients prefer this option to a piggyback system.

Q: Would you still select Rose K2 KC for oval cones post CXL?

A: Yes I certainly would. CXL does not change the overall corneal shape but only flattens it slightly by about 1.75D after a year or so.

Q: how long can Rose K be replace

A: I recommend replacement after 2 years as by this time most lenses show surface scratches which can affect vision and comfort.  Also precise aberration curves on the front of the lens can be destroyed over time with regular cleaning which affects best VA.

Q: Why have you not designed a hybrid lens?

A: I am in the process of doing so. Hopefully this will be available within the next 2 years.

Q: Which will be the best design for post corneal ring intacs?

A: Rings typically only flatten the apex of the cornea a little, but do not change the overall shape of the cornea so you often still have a cone. Use Rose K2 (KC) initially and if this does not give good results, try Rose K2 PG before moving to Rose K2 XL if corneal lenses are unsuccessful.

Q: Can the pt wear the XL more than 8 hours?

A: Depends entirely on the patient and the condition. Every patient is different. My advice is to initially recommend 8 hrs maximum wearing time per day and if at the end of this wearing time there are no issues then try extending it by 2 hrs a day up to a maximum of 12 hrs per day.

Q: Is it possible to put a SSACT when we have pingueculae? How do you evaluate SSACT in this case ?

A: Yes it is and the SSACT design is ideal for these cases. I would initially request a standard SSACT lift over a 90 degree segment. You need to state accurately the axis you require the SSACT as the laboratory need to incorporate prism at 270 to stabilise the lens.

Q: I have so many patients happy with the comfort of a scleral lens and I'm finding that many new patients are coming in asking for sclerals . How do I convince them to try corneal lenses again without losing them to another practice that will simply fit them with a scleral lens ??

A: If your patients are doing well in scleral lenses and there are no corneal or other issues, then my advice is to leave them as is and just monitor them regularly.  You need to have a very good reason like corneal vascularization for example to change a patient from sclerals to corneal lenses.  However you may want to consider changing them from sclerals to corneo-sclerals (XL) which provide good comfort and maximizes oxygen to the cornea.

Q: For cornea scar what design option should we employ?

A: If it is corneal scarring from an eye injury and not from an irregular cornea, then I would try Rose K2 PG first.  If you cannot achieve a satisfactory result from this design then move to XL.

Q: If the large Pterygium is there, and I want use the XL, could we use?

A: Yes definitely but you would need to use reverse ACT or reverse SSACT at the axis of the pterygium.

Q: Similar to case 3 PMD fitted with XL I got apical bearing at 4 o'clock while the rest is optimum, if the area become optimum the rest become apical clearance, what is your advice?

A:  Ideally PMD should be fitted to show clearance at the highest point at 4 o'clock.  However if the bearing does not cause staining or lift off at 270 then this is OK.

Q: What is the ideal time for fitting rose k lenses after cross linking surgery? (one month or two)

A: This depends on how quickly the corneal haze recovers.  BTW, it takes 3 months to get around 1D of flattening and then over the next 15 months the cornea continues to flatten only by an average of a further 0.75D.  So my recommendation is at 2 months or as soon as the corneal haze has cleared.

Q: Sometimes even when the right lens is found the comfort fluctuates, how long the patient can wear this lens?

A: This varies with individual patients, but if the comfort is not good for at least 8 hrs then you should consider fitting an alternative design.

Q: In post-transplant keratocones with glaucoma and valve, could a diameter smaller than that of the transplanted flap be advisable?

A: Not with Rose K2 XL as this design requires at least 1.3mm lap outside the limbus which is still likely to impinge on the valve.  However a corneal lens will not of course cause any issues.

Q: The superficial staining caused by the solution can appear in all kinds of RGP designs wearing?

A: Yes it certainly can.

Q: Is insertion and removal of XL lens different in any way from other Rose K lenses?

A: Yes, it is quite different to corneal lenses.  Please ask your lab for information regarding this.  Removal technique is shown on the Rose K website under the Rose K2 XL video fitting guide.

Q: What has been the feedback you get concerning Rose K fits in post cross linking cases, especially if there is also a laser procedure added (e.g. Athens protocol)?

A: I have not received any feedback to date on crosslinking accompanied by laser.  However for crosslinking only, many patients can wear Rose K designs successfully after the procedure.

Q: Do you fenestrate lenses as I often order, more so because I’ve inherited patients and they've already been using like this. 

A: XL does not normally require fenestrations because fitted correctly you have tear exchange occurring without the need for a fenestration. However you can fenestrate XL if you choose to.

Q: What is required to mention at the moment to order a toric periphery CL?

A: You will need to state only the degree of toricity you require. If you are unsure of this, then just order the standard toricity. The axis does NOT need to be stated unless you are also adding cylinder to the front of the lens.

Q: Many cases with early and mild stages of keratoconus in which corrected vision with glasses is 20/20. Very hard to compete this vision trying to correct with Rose K2 KC, mainly obtaining less vision. Is Rose K2 Soft an option in this kind of cases? 

A: Yes in early cases like this where vision is still good with glasses Rose K2 Soft is certainly indicated. 

Q: What is the recommended design for post corneal rings(intacs at 6mm)? 

A: Rings often only flatten the cone a few diopters so first try the normal Rose K2 KC design as you may still have a significant cone and this design may still be appropriate.  If this is not successful try the PG design and finally the XL design.

Q: Is it possible to apply the piggyback in the case of radial keratotomy?

A: Yes absolutely but because piggybacks reduce the amount of oxygen be careful about blood vessels growing along the scar lines. This may mean restricting wearing time.