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 Post subject: Extreme Keratoconus Fitting with Ultimate Ultracone GP lens
PostPosted: Sat Jul 07, 2007 10:51 pm | Post{ VIEW_SINGLE_POST } 

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Joined: Thu Apr 27, 2006 7:45 pm
Posts: 326
Location: Porto Alegre
When you treat advanced keratoconus there are certain cases in which the practitioner will give up to fit a special lens and will indicate the patient to a keratoplasty. Sometimes corneal transplant is the only viable alternative to the patient to restore his better vision and quality of life. However, what is the limit? Generally speaking, the ophtalmologists in Brazil who fit the RGP Ultracone design (a Soper Modifyed type), will have enough option up to a 60x45 diopters or little more.

Recent developments in the Ultracone design allowed us at IOSB to fit keratoconus patients with base curve lens as steep as 70+ diopters, sometimes we need to use a new version called Ultracone Mini-Scleral 3S GP lens. The overall diameter of this lens can be at a maximum size of 12.5mm. The posterior curves are generated after a computerized numeric control software utilizing aspheric base curves with reverse aspheric zones, allowing the lens to not touch the corneal apex, so we can achieve a non apical touch fit, with no bubbles under the lens. The remaining lens zones equally follows the natural corneal curvature straight to the edge. The software will also calculate the ideal minimum lens mass and volume so to avoid excessive weight and keep the lens stable and durable even if it is a superhigh DK material.

There are some cases in which this sort of fitting is desirable , and important to say, crucial to help the patient to have a normal life until he is able to perform a corneal transplant. In Brazil, a corneal graft can delay about 12 months or more to become available, with some rare exceptions. The idea is to benefit the patient with a reasonable visual acuity, comfort and to maintain corneal physiological health during the waiting time. It is of somewhat importance, on the other hand, that the patient had no significant leucoma or corneal opacities, if so, the practitioner should evaluate the cost x benefit aspect of this type of fitting. It takes a very reasonable chair time, and the practitioner may like to charge a higher fee what is perfectly reasonable.

I will present now some cases in which we had the fortune to succeed and we could benefit these patients with such extreme keratoconus condition. I will present the difficulties we found initially and gradually explain how we did to achieve the best lens to cornea relationship possible. I should remember my father, Dr. Saul Bastos, MD, who passed away in September 2004. He used to say: "Sometimes, the best fitting is not the ideal, but the best possible to obtain." He never could imagined what we was going to do a few years later, just to help his own patients with severe and advanced keratoconus. I am sure he is very happy with the results.

Patient M.L. 46 years old, severe advanced keratoconus in OS, she had previous corneal transplant in OD. She was not wearing her past lens for three months, needless to say that her keratoconus had a progression, so she was not tolerating her past lens. In this picture below a first trial lens tested with a base curve of 69.50x48 diopters (4.85 x 7.03 mm.) Lens Power -27.50 OAD 11.0 mm. Please note an apical touch over the central area with the presence of air bubbles. This means that the central curvature is not steep enough and the optical zone is larger the it should be, so there are the bubbles in approximately 6.0 mm diameter. The lens periphery also is quite steep, not allowing the desirable lens movement and it could produce lens adherence to the cornea.



Image


In the picture below there is a 71x48x45 base curve Ultracone Mini-Scleral GP lens, power -29.00 D and OAD 11.0 mm. Visual acuity of 20/25. Note that there is excessive tear pooling around the geometric center, what initially leaded us to find it was a central touch. The excessive pooling is masking the thin lacrimal layer in the top center, as you may see in the other picture next. At this time, patient was tolerating the lens with no complains, lens movement was up to 0.25 mm. and lacrimal exchange was very acceptable.

Image

Now, through the slit lamp examination, with a 45° light beaming view, white light beam, you can see the lateral view of the lacrimal layer under the lens. There is no touch at all, when the patient blinks it is very clear that there is tear under the lens at the top center apex of the cornea. The patient was instructed to use Visidic Gel every day prior to insert, and to readapt herself to the lens, so we recommended her to wear the lens one hour first day, and add one hour each new day until she find it was enough so she could accomplish with her daily tasks. We also asked her to come back in 4 days so we could evaluate if the fitting was doing fine.

Image
The slit lamp beam shows the presence of tear under the lens all over the apex, what would guarantee no scarring of the cornea. It is better noticed after the patient blinks.

Interesting (and funny) to say, when the patient came to the following up, I was examining her until Dr. Bittencourt arrive at the room, then I asked her how was the first few days wearing her new lens. She answered: "-I had some discomfort after a period but it was ok, not that much that could have made me take the lens off." So I asked her if the little pain was during the first or second hour, then she said: "-No, it was after 9 hours wearing the lens...." She had this symptom in the second day when she was supposed to be wearing the lens just 2 hours....

At the 4th day, and at the ten days and one month follow-up she had no symptom of pain, no scarring, no evidence of adherence, nor corneal abrasion. She was indicated to a corneal transplant, which she is waiting. This patient is too young to keep depending to a lens of this complexity, however she has a better vision with this correct eye then with the one she already had a PK years ago.

*This article was written by Luciano Bastos, and all rights belongs to IOSB - Instituto de Olhos Dr. Saul Bastos. If a third part wish to publish this article in another source, you may ask the IOSB staff to a permission. Please e-mail your message to
iosb@iosb.com.br

Luciano Bastos
Contact Lens Specialist and Technician (CLAO)
Technology Director of IOSB
Director of Ultralentes

Dr. Marcelo Bittencourt, MD.
Ophthalmologist - Cornea Specialist (UFRGS)
Clinical Director at IOSB

_________________
Luciano Bastos
Diretor & Instrutor ClĂ­nico de LC IOSB / Diretor Ultralentes
Membro:
Scleral Lens Education Society (US)
British Contact Lens Association (UK)
Contact Lens Society of America (US)
Contact Lens Manufacturer Association (US)


Last edited by luciano on Mon Nov 12, 2007 12:08 pm, edited 7 times in total.

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 Post subject: Re: Extreme Keratoconus Fitting with Ultimate Ultracone GP lens
PostPosted: Mon May 19, 2008 12:59 am | Post{ VIEW_SINGLE_POST } 

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Joined: Thu Apr 27, 2006 7:45 pm
Posts: 326
Location: Porto Alegre
Case Two



History

Patient M.F. 21 years old, diagnosed with binocular keratoconus when she was 15, by Dr. Saul Bastos, MD. Her condition had a strong progression in the past few years, which in turn, leaded us to treat an extreme case of progressive keratoconus in both eyes. In 2004 she was wearing the following Ultracone lenses: OD 59x45 -19.00 OAD 9.6 mm. and OS 62x45 -21.50 OAD 10.5 mm. VA 20/25 AO when the patient noticed problems and was confirmed the progression. Since then we have been able to overpass the difficulties with superb new Ultracone designs proper developed to conditions like you will face now.

She has both crystal, no scars, no leucoma or any other opacities in both of her eyes.

Image
Clear crystal cornea.


Right Eye (OD)

The patient developed a rapid, strong progression on her right eye over the past few years, and we had to extend the limit of her lens up to 69x48 -29.50 OAD 11.5 mm. so she could wear the lens without any scarring to the cornea and also properly vault the geometric center of the eye and the corneal apex. The patient was wearing this lens from August 2006 up to June 2007, when we noticed that her condition had a regression (?), as we found a 2.5 – 3.0 mm bubble over the central cornea, under her lens. The possible reasons to explain this event will be subject of another further study which we will be glad to share with all you that might have any interest. However I will mention that the patient had a drastic change on her diet in the past twelve months, due to her lessons in the Nutrition School, where she study. We all know that keratoconus is a condition of progressive deterioration of the cornea and it does not regress but stay stabilized or progress, however we have another patients which have similar evidences, so we need more data and further research on this particular subject.

Now, the patient was fit with a 66.50x45 -26.50 diopters, OAD 10.2 mm Ultracone design and this is the lens she is wearing up to 12-14 hours a day, with one interruption in which she insert a dip of a lubricant gel. VA is 20/30. In the pictures below you will see the past lens and now the final lens after she had a significant change on her topography readings for the OD.

Image
The prior lens fit in August 2006, with a 69.50x48 base curve.

Image
New, flatter Ultracone trial lens fit in June 2007, with a 66.50x45 base curve.
Image
The new lens, calculated to meet the exact requirements to be an ideal fit. Please note that we just put a minimal fluoroscein, using fluoroscein strip over the conjunctiva, so there is no interference of any liquid which could overflow the cornea and make a misjudge in its evaluation. There are tears all over the cornea under the lens.




Left Eye (OS)

The patient had a more severe keratoconus condition on this eye, she was wearing an Ultracone design with 71x48 base curve, -31.00 diopters and OAD of 11.5 mm but we were not satisfied with the results. The patient could not tolerate the lens more than 6 hours. She had some discomfort after this period.

Discussing this case with our staff, we found that the corneal pachymetry was enough to perform an implant of intrastromal corneal rings segments, so the patient went by this procedure and her topography readings regressed from 71 D. to a 58 D as referred to an average K readings. In this case, the first assumption was that it would be a lot easier to fit a flatter curvature and we could produce a RGP lens so she could wear for more time with comfort. We noticed that the temporal inferior portion of the segment provoked an elevation on this zone, making it difficult do fit even an Ultracone design. The problem occurs due to this elevation where even a special lens design will present some abrasion to the cornea, noticeable by the fluorosceine stain. We tried to fit another 4 lenses with different exccentricity values, modying the asphericity of the base curves and the geometric reverse transition but none of them worked properly.

We have other patients with similar difficulties, so we designed a new version of the Ultracone, called Ultracone PCR (Post-Corneal Rings) in which we faced the same situation with the corneal rings. The implants have a 5.5 – 6.5 mm diameter and we need a lens that avoid touching this elevation and also keep surrounding the cornea, with enough vaulting effect which will protect the central cornea. We developed the Ultracone PCR, special RGP lens, which is the very first design developed to overpass this sort of problem. This lens design was modified to adapt to a new condition that are very common in post-intrastromal corneal rings segments implants (Intacs, Ferrara, Keraring, Cornealring). We changed the posterior optical zone to a new value in which the asphericity of the reverse curve could prevent the cornea to be touched, at that particular portion of the cornea and also could produce an adequate fitting with a no apical touch and no bubbles.

In the following pictures we will show the previous lenses which did not work and then the new Ultracone PCR

Image
Note that the lens produces an abrasion over the temporal inferior segment zone of the cornea. See the fluoroscein stain.

This patient worn her new Ultracone PCR lens for about two weeks with no clinical symptoms, no scar and no erosion or abrasion in the cornea. However, she presented some problems due to her temporal ring which was causing some pain, with great risk of extrusion. It was not related to the lens, so she had to go by a new surgical procedure to extract this temporal segment. She was successfully refitted with a new Ultracone PCR RGP lens now as show below.

Image
Now, an Ultracone PCR fit, there is an excellent fluoroscein pattern and no abrasion to the cornea, no stain.

Obs. This thread is subject to modifications, updates and photograph updates. We have hundreds of these pictures and sometimes is somewhat exhaustive to find those who will better transmit the real idea of our findings.


*This article was written by Luciano Bastos, and all rightts belongs to IOSB - Instituto de Olhos Dr. Saul Bastos. If a third part wish to publish this article in another source, you may ask the IOSB staff to a permission. Please e-mail your message to iosb@iosb.com.br


Luciano Bastos
Contact Lens Specialist and Technician (CLAO)
Technology Director of IOSB
Director of Ultralentes

Dr. Marcelo Bittencourt, MD.
Ophthalmologist - Cornea Specialist (UFRGS)
Clinical Director at IOSB

_________________
Luciano Bastos
Diretor & Instrutor ClĂ­nico de LC IOSB / Diretor Ultralentes
Membro:
Scleral Lens Education Society (US)
British Contact Lens Association (UK)
Contact Lens Society of America (US)
Contact Lens Manufacturer Association (US)


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 Post subject: Re: Extreme Keratoconus Fitting with Ultimate Ultracone GP lens
PostPosted: Sun Aug 17, 2008 8:46 pm | Post{ VIEW_SINGLE_POST } 

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Site Admin

Joined: Thu Apr 27, 2006 7:45 pm
Posts: 326
Location: Porto Alegre
Case Three

Patient A.C.S. 19 years, diagnosed with binocular keratoconus. He was submitted to an intrastromal corneal ring segment implant in the right eye (temporal). His keratometry readings are 50.50 @ 165Âș 46.75 @ 75Âș VA 20/200 and his Rx -7.00 = -7.00 @ 125Âș.

The patient tried to wear contact lenses priorly but was unable to not succeed with the previous trials. We first tryed an aspherical RGP design with a base curve of 49.00 -6.50 OAD 9.2 mm but the lens descentered to a low position not acceptable for us neither the patient. Then a standard Ultracone RGP lens design was tested and the result was not good enough because the portion of the cornea where is localized the temporal inferior limit of the ring insists to touch the lens, so there are clear signs of corneal scarring in this particular area.

This is a very common finding in patients wearing RGP lenses after corneal intraconreal rings, despite the eventual success of the procedure. The solution was to fit an ultimate Ultracone PCR design, the first RGP design specifically developed to fit keratoconus patients with corneal ring segments. The lens parameters are 50x45 -7.25 OAD 10.4 mm. This lens design incorporate an aspheric reverse curve between the central and peripheral aspherical curves with a previous computer generated design, a proprietary design by Ultralentes.

In the picture below you will see the lens fit and ring segment with no apical neither lower portion touch. At the first follow-up the patient was wearing this lens for about 10 hours a day. The lens has a desirable movement and position, the patient is comfortable with the lens and there is no clinical symptoms or problems. VA is 20/15.

Image
Ultimate RGP ULTRACONE PCR Aspheric Design (OD)


This patient has a mild keratoconus on his OS with a Rx of -0.25 = -7.50 @ 154 Âș. so we fit a standard RGP Ultralentes lens with the following parameters: 45.00 -1.50 OAD 9.2 mm. aspheric design. VA 20-15. In the picture below you will note that the lens is positioned in a slight low position but still acceptable as the patients has no complain and there is no evidence of clinical problems.

Image
Aspheric RGP Ultralentes (OS)


Luciano Bastos
Contact Lens Specialist and Technician (CLAO)
Technology Director of IOSB
Director of Ultralentes

Dr. Marcelo Bittencourt, MD.
Ophthalmologist - Cornea Specialist (UFRGS)
Clinical Director at IOSB

_________________
Luciano Bastos
Diretor & Instrutor ClĂ­nico de LC IOSB / Diretor Ultralentes
Membro:
Scleral Lens Education Society (US)
British Contact Lens Association (UK)
Contact Lens Society of America (US)
Contact Lens Manufacturer Association (US)


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 Post subject: Re: Extreme Keratoconus Fitting with Ultimate Ultracone GP lens
PostPosted: Sun Aug 17, 2008 10:05 pm | Post{ VIEW_SINGLE_POST } 

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Site Admin

Joined: Thu Apr 27, 2006 7:45 pm
Posts: 326
Location: Porto Alegre
Case Four

Patient L.L.M. 34 years old. This patient has a very advance, extreme, unilateral keratoconus in her right eye. The topography readings were difficult to obtain, but we found readings as high as 78.12 @ 122 Âș x 62.37 @ 58Âș. Her VA in OD was 20/400 uncorrected.

This patient was fit with a Soper Ultracone design in November, 2000 by Dr Saul Bastos, MD. She wore her lens for two years, then she lost it. This patient did not come back to a refiting visit until now. As she has AV 20/20 in her left eye, she decided to give up for the right eye. Now after six years she returned to try again a new RGP lens. The problem is that she developed severe strabismus in her right eye due to lack of vision. We tried about three lens, all RGP Ultracone Advance Mini-Scleral designs, so we finally fit a lens with 70x49 -22.75 OAD 11.5 mm. We instructed the patient to instill Vidisic Gel (B&L) in her lens prior to insertion. Her VA now is 20/25 -3 and she wears the lens from 7 am up to 11 pm with no complain of confort neither vision. Despite its advanced condition, the cornea still have a stable pachimetry around 200 micras and we found Vogts Strae and minimal opacities which do not compromise her vision at all, considering all the factors and the final result.

The most surprising finding was that soon she inserted the lens she began to adjust her eye position and after three follow-up visits we found that she have great binocular vision and the eye gets back to the right position when wearing the lens. She is most satisfied with the results. The picture below shows the Ultracone Advance Mini-Scleral on her eye. “Sometimes the best fit possible is not that one we wish but the one possible to obtain” Saul Bastos, MD. Note that there are some microbubbles that simply disappear in 5 minutes. There is a video with the final result that I will include later on to confirm it.


Image
Ultracone Advance Mini-Scleral: 70x49 -22.75 OAD 11.5 mm VA 20/25-3

In the following image, slit lamp examination of the lateral image of the tear film with fluoroscein. The tear flow kindly all the way from one side to the other, promoting great tear exchange and preventing the cornea of any dissecation.

Image
The image is not the best as the patient moved the eye, but is shows apical clearence

The patient is very satisfied with the results, now she has perfect binocular vision, confort with lens, no complain and no evidence of epithelial erosions, just cristal clear cornea. She also managed to correct the strabismus in her OD. This fitting case and lens design is not that one which is fit in everyday practice.



Luciano Bastos
Contact Lens Specialist and Technician (CLAO)
Technology Director of IOSB
Director of Ultralentes

Dr. Marcelo Bittencourt, MD.
Ophthalmologist - Cornea Specialist (UFRGS)
Clinical Director at IOSB

_________________
Luciano Bastos
Diretor & Instrutor ClĂ­nico de LC IOSB / Diretor Ultralentes
Membro:
Scleral Lens Education Society (US)
British Contact Lens Association (UK)
Contact Lens Society of America (US)
Contact Lens Manufacturer Association (US)


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 Post subject: Re: Extreme Keratoconus Fitting with Ultimate Ultracone GP lens
PostPosted: Mon Aug 18, 2008 1:44 am | Post{ VIEW_SINGLE_POST } 

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Site Admin

Joined: Thu Apr 27, 2006 7:45 pm
Posts: 326
Location: Porto Alegre
Case Five

Patient C.D. 48 years old, binocular keratoconus. He is a long time patient from IOSB, he was treated by Dr. Saul Bastos since October 1991. This patient lives in Brasilia, DF and use to flight to Porto Alegre every 2 – 3 years to change his RGPs. He had a Penetrating Keratoplasty in his right eye in 1992 due to excessive corneal thinning. In 1994 he came to IOSB and was fit with an aspheric single base curve of 44.00 -1.00 OAD 9.2 mm. in his OD and a RGP Ultracone Mini-Scleral of 60x45 -16.50 OAD 11.0 mm.

In the following years his OD presented changes of curvature, progressing from the early 44.00 diopters after Tx to 47.75 diopters in 2004. Interesting to say that he was seen by my father a few days after my father was going to his surgical procedure, a coronary bypass. My father notes shows that the patient ordered his lenses and it was the same as the previously pair ordered in his past visit. In 2007, he returned to a follow-up visit and his left eye (OS) was presenting a corneal opacity. He was not tolerating the lens anymore. So we checked his topography as shown below.

Image
SimK Values OD: 54.50 94 Âș @ x 48.00 @ 4Âș (Keratoconus Recidive post-Tx?)
SimK Values OS: 71.00 @ 90 Âș (?) x 58.00 @ 180Âș (?) VA w/c finger counting


The equipment actually showed the question Mark in the axis values for the OS, but it is not important information in an advanced condition like this. The patient was worried about the transplant in his right eye (OD) but the overall condition of his cornea and the graft was not of any major concern. The new challenge was to fit his left eye, he was told that it would be better to indicate him to a corneal transplant in his OS, but the patient seriously asked to remain with RGP contact lens for as long as possible, even with a VA of 20/40-2.

We first attempted to achieve an apical clearance as we had to avoid with all means possible to prejudice his corneal visual axis. We tested an Ultracone mini-Scleral with the following parameters: 70x45 – 26.00 OAD 11.5 mm. The figure 5.1 below shows the first attempt I choose to test and the figure 5.2 shows the final lens ordered after I observe the trial lens pattern.

Image
Figure 5.1 Testing the first lens based on keratomery findings and observation

In most cases, a lens with the pattern above would be considered the best possible fit, but when I know I can improve the fitting because I know how to do this, the results are definitely better. The secret is to know what is happening, observe the fluoroscein pattern and the lens design. It requires knowledge and mental capacity to imagine, to find the modifications that should be done at the manufacturing process to achieve the best fitting relationship possible.

Image
Figure 5.2 The final lens: 70x48 -25.00 OAD 11.5 Ultracone Mini-Scleral

The result was great, the patient experienced confort again, actually very comfortable. The VA for the OS was 20/40 +3 with correction. This patient lives in a very arid region, very dry. BrasĂ­lia is one of the driest cities in Brazil, he uses Lacrigel as it is a viscous lubrificant that remains more time in the eye. he is able to wear his RGPs from 7 am up to 24 pm with no phisiological changes to his cornea. Recent developments in the Ultracone range of variations shows that the next lens to be fit in his left eye (figure above), an Ultracone PCR2 will produce an even better fluorescein pattern.

The Ultracone line of products were developed by my father Dr. Saul Bastos and me, and it incorporates the concept of Joseph W. Soper, OD, one of our mentors. However since my father passed away in the end of 2004, I put a serious effort in the extent of the limits, I actually go off limits to help patients like this. The Ultracone Mini-Scleral, Ultracone PCR and now the Bastos Semi-Sclerals designs are a great concept and we are mastering it. We believe that the develop of semi-sclerals aspheric RGPs is a health direction to go in many very complex cases.

Luciano Bastos
Contact Lens Specialist and Technician (CLAO)
Technology Director of IOSB
Director of Ultralentes

Dr. Marcelo Bittencourt, MD.
Ophthalmologist - Cornea Specialist (UFRGS)
Clinical Director at IOSB

_________________
Luciano Bastos
Diretor & Instrutor ClĂ­nico de LC IOSB / Diretor Ultralentes
Membro:
Scleral Lens Education Society (US)
British Contact Lens Association (UK)
Contact Lens Society of America (US)
Contact Lens Manufacturer Association (US)


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