(34 Total References)
Regional Advisory Board - The 6th World Congress on Controversies in Ophthalmology (COPHy)
Prof. Massimo Busin
Head of the Department of Ophthalmology, Villa Serena Hospital in Forli, Italy
Journal of Clinical Ophthalmology - Dove Medical Press
Professor of Ophthalmology, "Villa Serena" Hospital, Department of Ophthalmology, Forli, Italy
The easier-to-perform Descemets stripping ...
The easier-to-perform Descemets stripping automated endothelial keratoplasty (DSAEK) technique can offer outcomes that are close to DMEK, but it is possible for a wider number of surgeons, according to Massimo Busin, MD, Department of Ophthalmology, Villa Igea Hospital, Forl, Italy.
With DSAEK, Dr. Busin finds that preparing and evaluating the slightly thicker donor tissue is easier for eye banks, as is the transplant process for surgeons.
DSAEK has come a long way since its inception, Dr. Busin
It emerged toward the end of the last century when interest in developing techniques for selectively transplanting only part of the cornea arose, he
There were basically 2 approaches at the time.
In one, you would create a flap like for LASIK and perform an almost full-thickness trephination underneath and replace the piece under the cap, Dr. Busin
In the other technique, which later became known as DSAEK, donor stroma and endothelium was attached to the back of a full cornea.
first performed this in rabbit eyes in 1996 and presented at the American Academy of Ophthalmology
on it that year.
abandoned this initial approach, viewing the technique as awkward.
What I didnt know at the time was you dont need stitches, Dr. Busin
said, adding that by stitching the lamellar, the ensuing damage was so extensive that it would not survive in a human being.
However, when Gerrit Melles, MD, PhD, showed in 1998 that all that was needed to get the layers to stick to each other was an air bubble, everything changed, he
This revived the technique, and around 2002 the first DSEK [Descemets stripping endothelial keratoplasty] was performed in a human, Dr. Busin
Initially the donor (tissue) was prepared by hand, but later on we found that preparing using a microkeratome was the gold standard.
Thinning DSAEK down
One new development with DSAEK is that thin, reproducible lenticules can now be prepared, Dr. Busin
Known as ultra-thin DSAEK, this involves transferring only the endothelium and Descemets membrane, he
The results with thin donor tissue are better than with thicker tissue, he
usually welcomes an extremely thin graft of below 80 m. As he
performs 200 to 300 DSAEKs a year, he
prefers to prepare the tissue himself, rather than have it done at the eye bank.
This allows him to save a significant amount of money each year.
finds that the DSAEK approach can successfully serve many patients.
You can treat any patient with decompensated endothelium, Dr. Busin
said, adding that he
even selects the procedure for those with bad stroma.
Its the rare case where the cornea doesnt clear properly or there are residual scars that interfere, he
still performs DSAEK and may later go on and perform a DALK, leaving the DSAEK in place.
I had several cases where I was undecided whether it would be worth it to do DSAEK or just remove everything and do a PK, and in several instances Ive seen that doing DSAEK gives an improvement that you would not expect to start with, he
Editors note: Dr. Busin
has financial interests with Moria (Antony, France).
In the ongoing debate over which ...
In the ongoing debate over which endothelial keratoplasty procedure corneal surgeons should perform, Massimo Busin MD is taking the middle ground.
At the 5th EuCornea Congress
in London, UK, Dr Busin
advocated ultra-thin DSAEK (UT-DSAEK) for its ability to provide the best of DSAEK (descemet stripping automated endothelial keratoplasty) and DMEK (descemet membrane endothelial keratoplasty).
"In medio stat virtus - in the middle stands virtue," said Dr Busin
, quoting Aristotle and Horace.
shares DMEK's advantages over conventional DSAEK of faster visual recovery, better visual outcomes, and reduced immunologic rejection risk.
At the same time, UT-DSAEK
is simpler surgery than DMEK and minimises all types of postoperative complications."
According to Dr Busin
, consistently better quality graft tissue is the reason why UT-DSAEK
provides better vision outcomes than conventional DSAEK.
explained that central thickness is not the only parameter that matters.
"The simple value of central thickness is not sufficient to evaluate the 'quality' of a DSAEK graft, which is why a DSAEK lenticule with a 'good' stromal component is perfectly compatible with 20/20 vision, probably regardless of its central thickness.
Surface regularity and planar shape must also be taken into account," said Dr Busin, professor of ophthalmology, Villa Igea Hospital, Forli, Italy.
"Therefore, corneal surgeons advocating DMEK for its better vision outcomes should not be comparing DMEK against DSAEK in general, but against 'good DSAEK', which is DSAEK using a graft with a good quality
undertook the comparison between DMEK and 'good DSAEK' using data from his
own UT-DSAEK series.
The first issue he
considered was best spectacle-corrected visual acuity (BSCVA) at one year among eyes with 6/6 potential.
reported that in his
UT-DSAEK cohort, 39 per cent of eyes achieved BSCVA ≥6/6, 71 per cent saw ≥6/7.5, and 95 per cent achieved ≥6/9.
Proportions of eyes achieving those BSCVA thresholds after DMEK were 41 per cent, 80 per cent and 98 per cent, respectively.
Endothelial cell loss rates in the UT-DSAEK
and DMEK groups were similar as well (34 per cent and 36 per
Presenting data on speed of visual recovery, Dr Busin
showed that UT-DSAEK
had a clear advantage over DSAEK.
Although mean BSCVA levels at three and six months were slightly better after DMEK than UT-DSAEK
, Dr Busin
pointed out that mean preoperative logMAR BSCVA was also better in the DMEK versus UT-DSAEK group, 0.51 versus 0.76.
Compared to the same DMEK group, a better-matched UT-DSAEK cohort (phakic eyes with an average preoperative BSCVA of 0.55 in logMAR units) achieved better levels of vision in a shorter time.
"I am convinced that it is the preoperative condition of the patient and not a thin layer of stroma that makes a difference in vision outcomes," Dr Busin
The outcome of Dr Busin's
UT-DSAEK series also reduces concern about increased risk of immunologic rejection with DSAEK versus DMEK, although he
emphasised the importance of an appropriate corticosteroid treatment regimen postoperatively.
reported that the Kaplan-Meier cumulative probability of immunologic rejection was 2.5 per cent after UT-DSAEK
at one and two years, one per cent for DMEK at both follow-up intervals, and six per cent and 10 per cent at one and two years, respectively, post-DSAEK of the conventional type.
"Numerically, the rejection rate for UT-DSAEK
is twofold higher than DMEK, but the difference represents just one more case of rejection per 100 patients per year.
And, if we consider other possible complications, including the need for air re-injection, primary failure and tissue loss, then UT-DSAEK
compares quite well against DMEK," said Dr Busin
In his UT-DSAEK
series with Fuchs or pseudophakic bullous keratopathy, three per cent of eyes needed air re-injection, while both primary failure and tissue loss occurred at a rate of just one per cent. Data from DMEK series show air re-injection rates between 17 per cent and 77 per cent, a nine per cent primary failure rate and a tissue loss rate of up to 13 per cent.
explained that different techniques could be used to harvest the UT-DSAEK
used a double pass technique with a pivoting microkeratome.
"Accurate thickness could not be achieved after a single pass technique because of the instrument's tendency to cut deeper at the beginning of the dissection.
To compensate for that effect, a second pass was performed in the opposite direction of the first," he
Now, with the introduction of new linear microkeratomes that cut at a uniform depth throughout the dissection, Dr Busin
grafts with a single pass technique.
Massimo Busin: email@example.com
Professor Massimo Busin, ...
Professor Massimo Busin, Villa Serena Hospital, Italy.
Professor Massimo Busin, Villa Serena Hospital, Italy