Point/Counter

Would you recommend Descemet’s stripping alone for Fuchs’ dystrophy?

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POINT

Yes, in selected patients because clearance rates are high

Given the results achieved so far, I would (and do) recommend Descemet’s stripping for Fuchs’ dystrophy. In my practice, this still remains an option only for select cases of Fuchs’ and is not offered to every patient. Surgeons who wish to care for every case of Fuchs’ must still be confident with Descemet’s membrane endothelial keratoplasty.

Greg Moloney
Gregory Moloney

There are several important criteria that must be satisfied before surgeons can confidently offer a new procedure to a patient. First, of course, it has to work. Second, it must not introduce new and excessive risk. Finally, it should not preclude the patient from receiving the current standard of care. We are now confident that Descemet’s stripping meets these requirements.

We have been performing Descemet’s stripping since 2014 on select cases of Fuchs’, with dense central guttata and a healthy peripheral endothelial population. In initial studies, clearance rates were 80% with a mean recovery time of 12 weeks. This led to uncertainty about whom to offer the surgery to. Since the addition of Rho kinase (ROCK) inhibitor as a supplement, clearance rates are approaching 95% with a mean time to clearance of 4 weeks. This has increased our confidence in the procedure tremendously. Some patients will not clear despite good surgery and supplemental ROCK inhibitor. In our center, there have been three salvage DMEKs performed thus far. Importantly, the outcomes of these transplants appear good with corrected vision of 20/25 or better in each case. Therefore, we believe that a patient can be taken from Descemet’s stripping to a graft. Of course, the reverse is not true, and once grafted, a patient is a transplant recipient for life.

If patients are symptomatic enough to accept a DMEK (as this may eventually be required), if they are willing to accept weeks of blurry vision in the healing phase and if their endothelial profile fits, then we happily offer this procedure. We explain that we are not genetically “curing” them of their disease and perhaps we are only delaying the day that they feel they need a transplant, but for some patients this has now been 5 years. Finally, our eye bank and theater are happy with this surgery as the average surgical time is 6 minutes, with no use of graft tissue.

Gregory Moloney, MBBS, FRANZCO, FRCSC, is from Sydney Eye Hospital, Australia. Disclosure: Moloney reports no relevant financial disclosures.

COUNTER

Not routinely yet because there are unanswered questions

Descemet’s stripping only (DSO) may become the standard of care for uncomplicated Fuchs’ dystrophy, but at this time the results are not totally convincing. We and other centers had tried DSO years ago with less than ideal results. However, at that time we used a 6-mm area of stripping and did not supplement the eyes with ROCK inhibitors. In our series, each of the eyes had a non-healing area that persisted indefinitely, causing inflammation. Small areas of loose stroma probably caused the non-healing areas, so in doing DSO it is essential not to disrupt the recipient stroma. If the stroma is disturbed while stripping the Descemet’s membrane, we would recommend DMEK. Patients with diabetes may be more prone to have difficult stripping and areas of loose stroma, similar to the challenges when preparing tissue from donors with diabetes for DMEK.

Francis W. Price Jr.
Francis W. Price Jr.

A key question is whether DSO’s 4-mm clear zone will result in visual distortion. Experience with both IOLs and laser refractive surgery has shown that small 4-mm optical zones often have problems with glare and other visual distortions. Perhaps the profound glare and haze from central guttae in Fuchs’ makes the patients more tolerant of residual guttae outside the stripped central zone, or maybe not. Randomized controlled studies will be needed to see if the visual results of DSO match those of DMEK. Longer-term studies are also needed to assess how soon guttae redeposit in the stripped zone. Will the central area remain clear for a few years or for decades? How quickly will guttae grow outside the stripped zone?

Finally, we do not know yet whether the relatively low endothelial cell density in the area of stripping will remain stable over time — will DSO produce prolonged or transient corneal clearing? Only time will tell.

Francis W. Price Jr., MD, is an OSN Cornea/External Disease Board Member. Disclosure: Price reports he has received a research grant from Aerie Pharmaceuticals.

Click here to read the Cover Story to this Point/Counter.

POINT

Yes, in selected patients because clearance rates are high

Given the results achieved so far, I would (and do) recommend Descemet’s stripping for Fuchs’ dystrophy. In my practice, this still remains an option only for select cases of Fuchs’ and is not offered to every patient. Surgeons who wish to care for every case of Fuchs’ must still be confident with Descemet’s membrane endothelial keratoplasty.

Greg Moloney
Gregory Moloney

There are several important criteria that must be satisfied before surgeons can confidently offer a new procedure to a patient. First, of course, it has to work. Second, it must not introduce new and excessive risk. Finally, it should not preclude the patient from receiving the current standard of care. We are now confident that Descemet’s stripping meets these requirements.

We have been performing Descemet’s stripping since 2014 on select cases of Fuchs’, with dense central guttata and a healthy peripheral endothelial population. In initial studies, clearance rates were 80% with a mean recovery time of 12 weeks. This led to uncertainty about whom to offer the surgery to. Since the addition of Rho kinase (ROCK) inhibitor as a supplement, clearance rates are approaching 95% with a mean time to clearance of 4 weeks. This has increased our confidence in the procedure tremendously. Some patients will not clear despite good surgery and supplemental ROCK inhibitor. In our center, there have been three salvage DMEKs performed thus far. Importantly, the outcomes of these transplants appear good with corrected vision of 20/25 or better in each case. Therefore, we believe that a patient can be taken from Descemet’s stripping to a graft. Of course, the reverse is not true, and once grafted, a patient is a transplant recipient for life.

If patients are symptomatic enough to accept a DMEK (as this may eventually be required), if they are willing to accept weeks of blurry vision in the healing phase and if their endothelial profile fits, then we happily offer this procedure. We explain that we are not genetically “curing” them of their disease and perhaps we are only delaying the day that they feel they need a transplant, but for some patients this has now been 5 years. Finally, our eye bank and theater are happy with this surgery as the average surgical time is 6 minutes, with no use of graft tissue.

Gregory Moloney, MBBS, FRANZCO, FRCSC, is from Sydney Eye Hospital, Australia. Disclosure: Moloney reports no relevant financial disclosures.

PAGE BREAK

COUNTER

Not routinely yet because there are unanswered questions

Descemet’s stripping only (DSO) may become the standard of care for uncomplicated Fuchs’ dystrophy, but at this time the results are not totally convincing. We and other centers had tried DSO years ago with less than ideal results. However, at that time we used a 6-mm area of stripping and did not supplement the eyes with ROCK inhibitors. In our series, each of the eyes had a non-healing area that persisted indefinitely, causing inflammation. Small areas of loose stroma probably caused the non-healing areas, so in doing DSO it is essential not to disrupt the recipient stroma. If the stroma is disturbed while stripping the Descemet’s membrane, we would recommend DMEK. Patients with diabetes may be more prone to have difficult stripping and areas of loose stroma, similar to the challenges when preparing tissue from donors with diabetes for DMEK.

Francis W. Price Jr.
Francis W. Price Jr.

A key question is whether DSO’s 4-mm clear zone will result in visual distortion. Experience with both IOLs and laser refractive surgery has shown that small 4-mm optical zones often have problems with glare and other visual distortions. Perhaps the profound glare and haze from central guttae in Fuchs’ makes the patients more tolerant of residual guttae outside the stripped central zone, or maybe not. Randomized controlled studies will be needed to see if the visual results of DSO match those of DMEK. Longer-term studies are also needed to assess how soon guttae redeposit in the stripped zone. Will the central area remain clear for a few years or for decades? How quickly will guttae grow outside the stripped zone?

Finally, we do not know yet whether the relatively low endothelial cell density in the area of stripping will remain stable over time — will DSO produce prolonged or transient corneal clearing? Only time will tell.

Francis W. Price Jr., MD, is an OSN Cornea/External Disease Board Member. Disclosure: Price reports he has received a research grant from Aerie Pharmaceuticals.