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Analysis of the cornea donor data: an eye bank study

Authors:
  • Ankara Liv Hospital

Abstract

Objectives. To analyse 1.5-year data of our newly established eye bank and to evaluate the factors affecting donor quality. Methods. Our bank’s donor cornea data between July 2013 and November 2014 were retrospectively analysed. The effects of donor age, sex, and time from death to harvesting on the findings of specular microscopy were assessed. Results. A total of 139 corneas retrieved from 70 donors. The mean age of donors was 34.2±14.6 (5-64) years. The mean time from death to harvesting was 6.7±2.9 (1-13) hours; the mean time from collection to transplantation was 5.2±2.8 (1-14) days. Age had a significant negative correlation with mean endothelial cell count (ECC), a significant positive correlation between mean cell area (MCA) and standard deviation (SD). Time from death to harvesting had a significant negative correlation with cell count and 6A; it had a significant positive correlation with SD, the coefficient of variation, and MCA. Conclusion. According to the results of the present study, ECC, MCA, and SD levels were greater in younger donors. Endothelial morphology was altered as the time from death to harvesting was prolonged; however, the alteration in cell morphology was not severe enough to alter transplantation success with the corneas being harvested within the first 13 hours.
The European Research Journal
http://www.eurj.org
Original
Article
e-ISSN: 2149-3189 DOI: 10.18621/eurj.2016.2.1.30
Analysis of the cornea donor data: an eye bank study
Ayse Balikci Tufekci1, Sadik Gorkem Cevik1, Neslihan Parmak1, Rahmi Duman2, Mediha Tok Cevik3,
Burcu Kazanci4, Mehmet Emin Aslanci1, Ersin Yucel1
1Department of Ophthalmology, Bursa Yuksek Ihtisas Training and Research Hospital, Bursa, Turkey
2Department of Ophthalmology, Afyon Kocatepe University Medical School, Afyon, Turkey
3Department of Ophthalmology, Düzici State Hospital, Osmaniye, Turkey
4Department of Ophthalmology, Ankara Ulucanlar Training and Research Hospital, Ankara, Turkey
ABSTRACT
Objectives. To analyse 1.5-year data of our newly established eye bank and to evaluate the factors affecting
donor quality. Methods. Our bank’s donor cornea data between July 2013 and November 2014 were retrospec-
tively analysed. The effects of donor age, sex, and time from death to harvesting on the findings of specular
microscopy were assessed. Results. A total of 139 corneas retrieved from 70 donors. The mean age of donors
was 34.2±14.6 (5-64) years. The mean time from death to harvesting was 6.7±2.9 (1-13) hours; the mean time
from collection to transplantation was 5.2±2.8 (1-14) days. Age had a significant negative correlation with
mean endothelial cell count (ECC), a significant positive correlation between mean cell area (MCA) and stan-
dard deviation (SD). Time from death to harvesting had a significant negative correlation with cell count and
6A; it had a significant positive correlation with SD, the coefficient of variation, and MCA. Conclusion. Ac-
cording to the results of the present study, ECC, MCA, and SD levels were greater in younger donors. En-
dothelial morphology was altered as the time from death to harvesting was prolonged; however, the alteration
in cell morphology was not severe enough to alter transplantation success with the corneas being harvested
within the first 13 hours.
Eur Res J 2016;2(1):30-35
Keywords: Eye Bank; cornea; specular microscopy; endothelial; donor
Introduction
Eye banks are special medical units responsible for
harvesting donor corneal tissue required for the cornea
transplantation from suitable donors, preserving
harvested tissues under appropriate conditions,
evaluating tissue quality for transplantation,
transporting tissues to transplant centres under optimal
conditions, registering patients who apply for
keratoplasty procedure, as well as establishing and
maintaining communication with the
patients. Donor suitability, time from donor death to
tissue harvesting, cornea storage conditions, and time
of harvesting to transplantation are vital factors for
graft survival during the time of harvesting to
transplanting corneal tissue. Corneal storage duration
is dependent on corneal preservation methods (tissue
culture medium, organ culture, moist chamber);
corneal tissue should be transplanted as soon as
possible before irreversible degeneration occurs after
Address for correspondence:
Sadik Gorkem Cevik, Department of Ophthalmology, Bursa Yuksek Ihtisas Training and Research Hospital, Bursa, Turkey
Email: gorkemcevik@hotmail.com
Received: 04.08.2015; Accepted: 10.09.2015; Published Online: 04.03.2016
Copyright © 2016 by The Association of Health Research & Strategy
30
donor death and during storage [1].
As a result of continuously increasing the number
of patients entering keratoplasty waiting lists and
prolonged waiting durations, Turkish Ministry of
Health has recently funded the establishment of new
eye banks in various cities. As of the time of the
writing this paper, there are 28 functioning eye banks
in Turkey. Our eye bank was established in July 2013
by ministerial approval of Turkish Ministry of Health
and supplied 139 donor corneal tissues between July
2013 and November 2014. In the following we want
to assess the first donor data of our newly established
eye bank.
Methods
Data of donor corneas harvested at Bursa Yuksek
Ihtisas Training and Research Hospital Eye Bank
between July 2013 and November 2014 were
retrospectively reviewed. Data on donor age, sex, time
of death to harvesting, time from collection to
transplantation, serology results, specular microscopy
(SM) results, and donor usage were recorded. In
specular microscopy, the Centre Method was used to
determine the corneal endothelial count and
endothelial structure (polymegathism and
pleomorphism) (Konan Eye Bank Kerato Analyzer,
Konan Medical Inc., Japan). The effects of donor age,
sex, and time from death to cornea harvesting on the
findings of specular microscopy were analysed. The
local ethics committee approved the study. After being
harvested from the cadavers using the sclerocorneal
button technique, donor corneas were preserved in the
preservation solution (Eusol C, Alchimia, Italy) at
4°C; and endothelial photographs were taken to be
examined for four times from all corneas by the same
person using specular microscopy. For each donor
cornea, endothelial cell count (ECC), mean cellular
area (MCA), standard deviation (SD), hexagonality
ratio (6A), and coefficient of variance (CV) were
recorded. The donors were categorized into four age
groups. Donor gender distribution, corneal side
distribution, endothelial count, SD, CV, 6A, MCC,
time from death to harvesting and time from collection
to transplantation were compared across the four age
groups.
Statistical analysis
Descriptive statistics included mean, standard
deviation, median, minimum, maximum, frequency,
and percentage. The distribution of study data was
tested with the Kolmogorov-Smirnov test.
Quantitative data were analysed with ANOVA and
Kruskal-Wallis (Mann-Whitney U) tests. Chi-Square
test was used for the analysis of qualitative data. SPSS
22.0 software package was used for all statistical
comparisons.
Results
Among 70 donors included in the study, 16 (23%)
were female, and 54 (77%) were male. During our
study period, 139 corneal tissues were retrieved from
70 donors. A pair of corneas was harvested from 69
donors and a single cornea from 1 donor. The mean
age of the donors was 34.2±14.6 (5-64) years. The
mean time from death to harvesting was 6.7±2.9 (1-
13) hours; the mean time from collection to
transplantation at different centres was 5.2±2.8 (1-14)
days. The mean age of the transplant recipients was
45.8±25 (1-88) years at various centres. The obtained
corneas were serologically tested using anti-HIV,
HBsAg, anti-HCV and VDRL tests. Two corneas were
HBsAg positive and were thus disposed of.
Another cornea was disposed of by a recipient
centre due to suspected infection. The findings of
specular microscopy, age and sex group distribution
of corneal tissues were shown in Table 1.
There were no significant differences between the
age groups on gender distribution and the distribution
of corneal tissue side. The cell count was significantly
greater in the first age group (5-19 years) compared
with the second (20-34 years), third (35-49 years), and
fourth (50-65 years) age groups (p<0.001). The cell
count was significantly greater in the second age group
compared to the 3rd and 4th age groups (p<0.001)
(Table 2). The SD level was significantly lower in the
first age group compared to the second, third, and
fourth age groups (p<0.001). It was also significantly
lower in the second age group compared to the fourth
age group (p<0.001) (Table 2). There were no
significant differences between the age groups on CV,
6A, time from death to harvesting, and time from
collection to transplantation (Table 2). The first age
group had a significantly lower MCA compared to the
second, third, and fourth age groups (p<0.001) The
MCA level was significantly lower in the second age
group compared to the 3rd and 4th age groups (p<0.001)
Eur Res J 2016;2(1):30-35 Cornea donor data
31
( Table 2).
Cell count, SD, CV, 6A, and MCA levels were not
significantly different between both genders (Table1).
Time from death to harvesting had a significant
negative correlation between cell count and 6A
(p=0.005). It had a significant positive correlation with
SD, CV (p<0.001 for both), and MCA (p=0.011)
(Table 3). Twenty-nine (21%) of the harvested corneas
were used at our hospital while the remaining 108
(79%) corneas were sent to other requesting
institutions. Two corneas had HBsAg positivity and
were thus disposed of.
Discussion
Today, there is an estimated 4.9 million patients
with bilateral corneal blindness worldwide, especially
in the developing countries, who may potentially
regain their visual ability with corneal transplantation.
According to the World Health Organisation data,
120.000 keratoplasties (KP) operations were
performed in 2000 worldwide [2, 3]. According to the
data of the Turkish Ministry of Health, the numbers of
keratoplasty operations were 1784 and 1921 in 2012
and 2013, respectively. The official number of patients
who are in the cornea waiting lists is 4822, although
unofficial estimates put the number at 10.000 [5, 6].
Evaluation of donor candidacy according to
certain standards is vital to operational success and
preventing complications. For this purpose, the
European Eye Bank Association (EEBA) and the Eye
Bank Association of America (EBAA) have set up the
minimum medical standards for donor candidacy [7,
8]. FDA undertakes supervision and certification of
the eye banks in the United States. The available
standards are reviewed twice a year, published by the
American Academy of Ophthalmology, and
!!!!!!
Table 2. Age groups with the distribution of specular microscopy findings.
Age groups
5-19 Years
20-34 Years
35-49 Years
50-65 Years
p
Cell Count
3319 ± 361
2947 ± 358*
2685 ± 366*#
2518 ± 326*#
<0.001
SD
95.2 ± 42.6
113.7 ± 31.7*
114.9 ± 26.9*
133.0 ± 35.5*#
<0.001
CV
30.3 ± 8.9
32.7 ± 6.4
30.3 ± 5.0
32.6 ± 5.8
0.051
6A
63.9 ± 10.0
59.2 ± 6.9
59.9 ± 8.2
61.5 ± 8.5
0.111
MCA
304.8 ± 38.5
343.2 ± 41.5*
377.7 ± 52.9*#
403.8 ± 53.8*#
<0.001
Harvesting time (h)
6.1 ± 2.7
6.7 ± 3.2
6.7 ± 2.8
7.3 + 3.0
0.504
Transplantation time (h)
4.7 ± 3.1
5.7 ± 3.2
4.8 ± 2.5
5.7 ±2.4
0.212
Recipient Age
32.6 ± 25.6
42.6 ± 23.9*
55.4 ± 21.1*#
52.1 ± 20.7*
0.001
SD= Standart deviation, CV=coefficient of variance, 6A=hexagonality ratio, MCA=mean cellular area,
Kruskal-Wallis / ANOVA, * p< 0.05 vs. 5-19 years age group / # p< 0.05 vs. 20-34 years age group
!
!
!
!
!
!!
Eur Res J 2016;2(1):30-35 Tufekci et al
!!!!!!
Table 1. Specular microscopy, age and sex group distribution of corneal tissues
Median
Mean ± SD
Donor Age
34
34.2 ± 14.6
Age Groups
34 (24.5%)
37 (26.6%)
43 (30.9%)
25 (18.0%)
Cell Count
2857
2884.0 ± 457.3
SD
106.0
112.7 ± 36.2
CV
30.0
31.4 ± 6.7
6A
61.0
61.1 ± 8.6
MCA
347.0
354.3 ± 58.4
SD= Standart deviation, CV=coefficient of variance, 6A=hexagonality ratio, MCA=mean cellular area
32
distributed to eye banks that are members of EBAA
[9].
A donor cornea having appropriate criteria for
transplantation is one of the most important factors
determining the keratoplasty success. Therefore, a
harvested cornea should undergo a specular
microscopic and serological evaluation before
keratoplasty. Some studies using specular microscopy
have shown that race, sex, and age of a person may
alter morphological properties of the endothelium [10,
11]. It has also been reported that certain factors such
as time of donor death to cornea harvesting and cause
of donor death may also influence endothelial
morphology [12, 13].
Some studies have reported that endothelial count
is the most important factor for donor quality.
Endothelial cell density is markedly reduced until
early puberty, especially in the first couple of years
after birth. Former studies have shown that the mean
endothelial cell count is reduced, and pleomorphism
is markedly increased after the age of 50 [14, 15].
Mean endothelial cell count is reportedly decreased by
0.3% to 0.6% each year while polymegathism and
polymorphism simultaneously increase [16, 17].
Endothelial cell density is reduced between the second
and eighth decades, dropping from 3000 to 4000
cell/mm2 on average to as low as 2600 cell/mm2 on
average. The hexagonal cell percentage also drops
from 75% to 60% [18], reducing the rate of usage of
corneas obtained from elderly donors for
transplantation. However, many studies have reported
that corneas from advanced-age donors can also be
sometimes used for transplantation, and thus donor
age does not affect donor survival. Linke et al. [17]
showed that 32.1% of corneas from donors aged over
80 years met the appropriate criteria for
transplantation. Patel et al. [19] similarly
demonstrated that 80% of corneas from advanced age
donors had suitable standards for transplantation.
According to EBAA criteria reported in 2006, donors
should be between 10 and 75 years of age [20].
Besides, the minimum medical standards set by EEBA
in 2013, as well as those set by EBAA in 2012, do not
specify an age limit for donor eligibility [7,8]. Kartal
et al. [21] reported that ECC showed a significant
negative correlation with age, being significantly
greater in the first two decades of life. Likewise, our
study revealed a negative correlation between ECC
and age. Cell count was significantly higher in the first
age group (5-19 years) compared with the second (20-
34 years), third (35-49 years), and fourth (50-65 years)
age groups. Cell count was significantly greater in the
second age group compared to the third and fourth age
groups (Table 3). Our study also demonstrated a
positive correlation between age and MCA, SD
values. SD and MCA levels were significantly lower
in the first age group compared to the second, third,
and fourth age groups. MCA was significantly lower
in the second age group compared to the 3rd and 4th
age groups, while SD was significantly lower in the
second age group than the fourth age group. CV and
hexagonality did not show any age-based differences.
Some studies in the literature failed to show any age-
associated differences in CV, MCA, and hexagonality,
although some others have reported age-related
differences in MCA [22, 23]. Kartal et al. [21] showed
that CV and MCA were significantly lower in Group
1 and 2 (0-40 years of age). In our study, mean
endothelial count was 2884.0±457.3, mean SD was
112.7±36.2, mean CV was 31.4±6.7, mean MCA was
354.3±58.4 and mean hexagonality was 61.1±8.6.
Since our mean donor age was lower than those
reported in the literature, specular microscopy findings
were ideal for transplantation in all of our donors.
Some studies investigated gender-based differences in
endothelial cell morphology, some of them reporting
ECC differences between both genders, but some
others not [24, 25]. Kartal et al. [21] reported that
female donors had a greater MCA, while a study from
India, reported higher CV in female donors [26]. Our
results did not reveal any significant difference
between both sexes. Previous studies have shown a
significant impact of time from donor death to cornea
harvesting on endothelial count [17, 27]. EBAA
recommends cornea harvesting within 20 hours in
those aged less than 50 years, and within 18 hours in
!!!!!!
!
Table 3. Time from death to harvesting (Spearman Correlation)
Cell Count
SD
CV
6A
MCA
Time from death to
harvesting (Hour)
r
-0.240
0.349
0.394
-0.191
0.224
p
0.005
0.000
0.000
0.031
0.011
SD= Standart deviation, CV=coefficient of variance, 6A=hexagonality ratio, MCA=mean cellular area,
33
Eur Res J 2016;2(1):30-35 Cornea donor data
those aged equal to or greater than 50 years of age
[20]. As a general rule, it is recommended that corneal
harvesting should be completed within 12 hours [28],
although there is still no consensus regarding the upper
limit of this time, and it may well be prolonged in
some cases [29]. Kartal et al. [21] showed that ECC
was greatest in the ≤3 hours group, although the
difference was statistically non-significant. Our study
showed a significant negative correlation between
time from death to cornea harvesting and cell count,
6A. There was, however, a significant positive
correlation between time from death to cornea
harvesting and SD, CV, and MCA.
These results suggest that donor cornea quality is
reduced as the time to the collection is increased.
However, corneal endothelial structures did not
undergo a degenerative process to preclude
transplantation since corneas were harvested within
maximum 13 hours. The harvested corneas should be
serologically tested with anti-HIV, HBsAg, anti-HCV,
and VDRL tests. Some domestic prevalence studies at
different times have found a mean HBsAg positivity
rate of 5% and a mean HCV positivity rate over 0.5%
[30].
Kocazeybek et al. [31] reported corresponding
figures of 6.6% and 0.9%. Our study revealed HBsAg
positivity in two corneas, which were disposed of. One
other cornea was disposed of by another centre due to
suspected infection.
Of the donor corneas collected by our bank over a
period of 1.5 years, 21% were used for transplantation
by our hospital and 79% by other institutions. Various
studies have reported that about 30% of donor corneas
cannot be used owing to either serological results or
an inappropriate endothelial morphology on specular
microscopy examination [8]. We suggest that, we had
a higher rate of cornea usage and we generally used
high-quality corneas, because our eye bank preferred
relatively younger donors, it rejected corneas with
suspected infection due to prolonged stay at intensive
care unit or the corneas which would be inappropriate
for transplantation due their general appearance, and
it harvested corneas at 6.7±2.9 hours on average after
donor death.
The harvested corneas were sent by our eye bank
to other clinics as soon as possible when they were not
to be used at our hospital. Time from harvesting to
transplantation was 5.2±2.8 (1-14) days on average at
other clinics.
In conclusion, we revealed that ECC, MCA, and
SD values were greater in younger donors; endothelial
morphology was altered as the time from death to
harvesting was prolonged; however, the alteration in
cell morphology was not too severe to alter transplant
success with the corneas being harvested within first
13 hours. Eye banks should meticulously work in
every step from donor harvesting to cornea
transplantation. High-risk donor corneas should not be
harvested. Harvested corneas should be examined
serologically, as well as under specular microscopy,
and they should be sent to centres of transplantation
as soon as possible.
Conflict of interest
The authors disclosed no conflict of interest during
the preparation or publication of this manuscript.
Financing
The authors disclosed that they did not receive any
grant during conduction or writing of this study.
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Eur Res J 2016;2(1):30-35 Cornea donor data
... However, few comparable studies detailed early findings within first 2 years of establishment of EBs. [10][11][12][13][14][15] The largest EB of India started with only 20 corneal transplants in the year 1989. [11] In the present EB, 54 corneas were retrieved during the first 2 years of inception. ...
... Another EB in Eastern India collected 130 corneas in the first 2 years. [12] An EB in Turkey reported early data over 17 months stating a retrieval of 139 corneas from 70 donors, [13] while the Central Eye Bank of Iran managed to collect 856 corneas in its initial 2 years but did not state reasons for high procurement rate. [16] A study from New Zealand reported a collection of 206, while the Lions Eye bank of South Australia reported a collection of 198 in the first 2 years. ...
... [3] The present study shows that tissue collection was more in the first year of establishment than the second year while in all other studies the numbers increase with time. [10][11][12][13][14][15] This is due to suspension of eye banking activities with the advent of the SARS-nCOV-2 (COVID-19) pandemic after March 2020, [9,17] with resumption of limited collection activities after August 2020. [18] Studies from most EBs in other institutions report that the majority of donors were over 50 years of age. ...
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Context: There is a global need for quality eye banking practices and sensitization of primary care physicians toward corneal donation. Aims: To evaluate performance of a recently established eye bank (EB) and quality of corneas obtained, and identify areas of improvement during procurement and utilization of donor corneas. Settings and Design: This retrospective observational study is based on records of corneas collected through hospital cornea retrieval programme (HRCP) in the EB of a tertiary care institution during the first 2 years of its establishment. Methods and Material: Data on demographic characteristics of donors, death-preservation interval, specular microscopy parameters of corneas, indications for utilization, and reasons for non-utilization of corneas were collected. Statistical Analysis Used: Means, standard deviation, range, frequencies, and proportions were analyzed. Spearman’s correlation coefficient and Kruskal–Wallis test were applied taking P < 0.05 as significant. Results: The EB retrieved 54 corneas from 27 donors with mean age 42.3 ± 24.2 years. All tissues were preserved in Cornisol®. Majority (50%) of transplantable tissues had an endothelial cell density (ECD) between 2,000 and 2,500 cells/mm2. ECD decreased significantly with increasing age (Spearman’s ρ -0.747, P < 0.001; Kruskal–Wallis P < 0.001). Overall utilization rate of tissues was 87.04% (47/54), and utilizable corneas (50/54, 92.6%) were mainly used for optical purposes (34/50, 68%). Conclusions: Successful HCRP of the recently established EB has shown considerable promise in terms of quality and utilisation of corneas. There is need for active involvement of primary care physicians in contributing to increasing voluntary eye donation through awareness, advocacy, and social mobilization
... In our study, young donors had higher ECD and hexagonality, but CV was not correlated to age. While ECD significantly declined across all ages, we found no significant difference in hexagonality from ages 20 to 60 and a significant decline in donors aged 60 to older than 80. Tufekci et al. and Gupta et al. also reported that hexagonality and CV did not change with age [11,24]. Several studies on Indian eye donors reported a similar decline of ECD with age [6,14]. ...
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Background In India, donor eye collection and promotion of eye banking are insufficient to meet the needs. By adequately evaluating donor corneas, eye banks can maximize the number of viable corneas for transplantation. This study evaluated donor corneal tissue based on age, lens status, and cause of death by their morphology and endothelial cell count via slit lamp and specular microscopy. Methods We conducted a prospective observational study of all eye bank donor corneas indicated for eye donation at a tertiary hospital and research center in Western Maharashtra between September 2019 to December 2021. We evaluated the corneoscleral discs by slit-lamp microscopy specular microscopy. We analyzed donor corneas quantitatively and qualitatively and graded them accordingly. We also collected blood samples for serological testing and the donor's behavioral and family medical histories. Results We collected 94 eyes from 47 donors; the mean age of the donor population was 48.2 years, and most donors were aged 41 to 80 years. Thirty-one donors (65.96%) were male, and 16 were female (34.04%. For preservation, we used Cornisol (Aurolab, Madurai, India) in 36 cases (77%) and McCarey-Kaufman medium in 11 cases (23%). We found a mean endothelial cell density (ECD) of 2214.40/mm2, with hexagonality of 53.05%, and a coefficient of variation of 38.01. Further, we observed that ECD and hexagonality of cells in phakic donors were significantly greater than that of pseudophakic (PP) donors. Moreover, ECD and hexagonality significantly decreased in donors with the chronic disease compared to those who had a sudden, unexpected death. Conclusion Corneal grafts from younger donors, phakic donors, and donors who experienced an acute cause of death were qualitatively and quantitatively significantly better than those of older donors, PP donors, and donors who experienced sudden, unexpected death. Therefore, eye bank specular examination can improve tissue utilization and transplantation success. Therefore, we strongly recommend that eye bank personnel evaluate their donor tissue with a specular microscope to enhance the quality of eye care.
... There was a reduction in the number of tissue resource centers connected to the eye bank in 2013, and this resulted in a reduction in the number of corneas procured from donors per year in 2013 and thereafter (Figure 4). Although the number of corneas procured per year in this study was similar to the number reported for other eye banks in Turkey (92.66-106.1 corneas per year), 8,10,11 this is far lower than the number reported for eye banks in countries such as the United States, 13 Brazil, 14 India, 15 and Iran. 16 This low rate of cornea procurement could be the result of donor candidates' lack of trust in the health care system, insufficient legal regulations, and/or religious beliefs, or there may be other factors. ...
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Objectives: We evaluated 23 years of data for cornea donors at the Istanbul Faculty of Medicine Lions Eye Bank. Materials and methods: Annual statistics of corneal donors between 1996 and 2019 were reviewed retrospectively. Records for 2008 and previous years were compared with records for 2009 and years thereafter,to assess donor demographics and reasons for discard of corneas. Results: A total of 3849 corneas were obtained from 2018 donors during a 23-year period. Of these, 26 donors (11.2%) were registered, whereas 1792 (88.8%) did not register any decision for donation. There were 210 (5.46%) corneas discarded for positive serology and 291 (7.56%) for unsuitable tissue morphology, and 3348 (86.98%) corneas were determined to be suitable for transplant. For the cause of death in 2009 and subsequent years, the incidence of trauma was lower (P = .001) compared with the years previous to 2009, whereas incidence of cardiac pathology (P = .014) was higher. The number of donors older than 50 years was higher for 2009 and years thereafter, compared with data from earlier years (P = .024). The rate of discarded corneas for unsuitable tissue morphology (P = .004) and total discarded corneas (P = .027) decreased in 2009 and years thereafter. The rate of discarded corneas for HIV was higher after for 2009 and years thereafter (P = .047), whereas the rate of discarded corneas for syphilis was significantly higher for 2015 and years thereafter (P = .001). Conclusions: This study evaluated the most extensive eye bank data in Turkey and found that advances in lamellar surgery techniques and improvements in specular microscopic facilities have expanded the pool for cornealtransplants to include tissues from older donors. Moreover, the incidence rates for HIVpositive and syphilis-positive serology tests in discarded corneas have increased over time.
... mean SD was 112.7 (±36.2), mean CV was 31.4 (±6.7), and mean hexagonality was 61.1 (±8.6) [22]. The ECD was significantly higher in the first age group (5-19 years) compared to rest of the age groups while findings of CV and hexagonality did not show any age-based differences. ...
... Similar to our study, Patel et al. also found a significant correlation between advancing donor age and lower ECD, where in age group <20 years the mean ECD was 3175 cells/mm 2 while in age group of >81 years the mean ECD was 2917 cells/mm 2 . In a study by Tufekci et al., [16] the mean ECD was 2884.0 (±457.3), mean SD was 112.7 (±36.2), ...
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Aims and Objectives: The aim of the study is to assess the knowledge, attitude, and practice regarding eye donation in patients attending outpatient department of a tertiary care hospital. Materials and Methods: The data were collected by the questionnaire method from 500 patients waiting in outpatient department of ophthalmology. The questionnaire included questions pertaining to demographic profile, literacy, occupation, awareness about eye donation, willingness to donate, reasons for not pledging, and the sources of information. Results: Percentage of awareness of eye donation was equal in males and females. Significantly less awareness of eye donation was found in illiterate individuals (P < 0.0001) and Muslims (P < 0.0001). 66.6% participants were aware of eye donation and eye camps were the major source of information. 51.50% were willing to pledge their eyes. Lack of awareness was the major reason for not willing to pledge in 32.91% participants. Chi‑square analysis between “awareness” and “willingness” groups showed that age group, gender, residency, and occupations were independent factors contributing to willingness to donate, while religion and education showed significant association between awareness and willingness(P < 0.05). Participants who were initially not aware about eye donation (33.6%), after being counseled showed positive responses of willingness to pledge. Conclusion: The data showed that most of the people were aware about eye donation and were willing to donate their eyes; however, the attitude and practice showed mixed responses. Participants had misconceptions about eye donation. Therefore, to reduce the burden of avoidable corneal blindness effective measures should be taken by ophthalmologists, physicians, and especially religious leaders to educate and motivate people for eye donation
... The percentage of hexagonal cells as well decreases from 75% to about 60%. 22 All the participants in the present study were younger than 50 years in age; hence, the effect of age on endothelial parameters has been minimized. ...
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Purpose To determine whether there are differences in the central corneal thickness (CCT), retinal nerve fiber layer (RNFL), and ganglion cell-inner plexiform layer (GC-IPL) in women with iron deficiency anemia (IDA) and vitamin B12 deficiency anemia (B12DA). Methods The patients were divided and evaluated in three groups as IDA (group 1), combined IDA-B12DA (group 2), and healthy females (group 3). Each group constituted 35 subjects. CCT, endothelial cell density (CD), the coefficient of variation (CV), and hexagonality (HEX) values were evaluated. Superior, nasal, inferior, and temporal retinal nerve fiber analysis were done, and mean thickness of GC-IPL complex was also evaluated. Results CCT was found to be less (thin CCT) in group 2 as compared to group 1 and group 3 (P = 0.016 and P = 0.013, respectively). While CD measurements did not vary significantly between the groups, CV value was found to be lower in the control group as compared to that in the other groups (P = 0.001 and P = 0.002, respectively). HEX and the thicknesses of all RNFL and GC-IPL were lower in both the anemic groups as compared to the control group (P = 0.012 and P = 0.013, respectively); however, no significant difference was determined between the anemia groups. Conclusions It should be noted that anemia is a common clinical picture particularly seen in women, and there may be a tendency toward corneal and retinal disorders in these patients. The present study found that presence in the patients with IDA and with combined IDA-B12DA may have influenced endothelial functions; also the patients with anemia had significantly thinner CCT than healthy controls. Translational Relevance Optical coherence tomography and specular microscopy measurements may provide important data for early diagnosis and treatment of both corneal and retinal diseases according to the type of anemia in anemic women.
... Similar to our study, Patel et al. also found a significant correlation between advancing donor age and lower ECD, where in age group <20 years the mean ECD was 3175 cells/mm 2 while in age group of >81 years the mean ECD was 2917 cells/mm 2 . In a study by Tufekci et al., [16] the mean ECD was 2884.0 (±457.3), mean SD was 112.7 (±36.2), ...
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Aim: The aim of this study was to analyze the endothelial cell count and morphology of the endothelial cell of donor corneas using Eye Bank Specular Microscope (EBSM). Materials and Methods: Eye bank data of 100 donor corneas procured and processed between January 2016 and December 2017, at an eye bank associated with a medical college hospital were retrospectively analyzed. Endothelial cell density (ECD), coefficient of variance (CV), and percentage age of hexagonality (6A) of donor cornea were compared across different age groups, gender, and phakic status of the donor tissue. Results: The mean age of the donors was 63.53 ± 19.92 (range 15–92 years). The mean ECD of the donor cornea was 2708.93 ± 271.52 cells/mm2; the average CV was 28.37 ± 6.3; and the average percentages of hexagonal cells were 63.85%. The cell count was significantly greater in the age group of
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Background – Cornea transplantation has an important role in reducing the burden of corneal blindness but availability of corneal donor tissue is a significant limitation. The overall utilization of available cornea is further limited by the quality of donor corneal tissue.Specular microscopic evaluation of donor cornea is emerging as an indispensable tool of endothelial evaluation. Aim – Aim of this study to do an age based specular microscopic evaluation of first 50 corneal tissue obtained through hospital cornea retrieval program at a newly established eye bank in Eastern India Material and method – Total 50 corneo-scleral donor tissue were included in study after excluding the contraindication of cornea donation. Three tissues were could be not included in final assessment due to unavailability of specular microscopic image.47 tissues were divided in different age groups – <20 years (10 tissues),20-40 years (10 tissues),40-60 years (10 tissue) an >60 years (17 tissues). Specular microscopic evaluation was done with Konan eye bank keratoanlyser - CellChek® D® (Konan Medical, Irvine, CA). Endothelial cell density (ECD), corneal thickness (CT), coefficient of variance (CV) and percentage of hexagonal cells (6A) were evaluated and correlated with age. Result – The average age of donor was 47.02 years. The average CT, ECD, CV and 6A were 523.42 +/- 16.37 micron, 2222.87 +/- 514.62 cells/mm2, 35.27 +/- 4.04, 53.06 +/-8.30 % respectively.The difference in ECD was significantly high in age group <20 years than in comparison to those between 20-40 years (p value - 0.018),40-60 years (p value - 0.003) and more than 60 years (p value - 0.0001). There was a progressive decrease in ECD count with age but the change in ECD count between age group 20-40years and 40-60 years was not significant (p value - 0.12).ECD was significantly low in age group > 60 years in comparison to all other group i.e.<20 years (p value – 0.0001), 20-40 years (p value - 0.003) and 40-60 years (p value - 0.016). There was no significant difference in any other parameter (CT, CV, 6A) in any of the age group. Conclusion - Eye bank specular microscope is an important tool in proper evaluation of donor corneo-scleral button. The ECD is significantly high in tissue from younger age of donor with a progressive decrease in age.CCT,CV and 6A are found to have no correlation with age.
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Corneal diseases represent the second leading cause of blindness in most developing world countries. Worldwide, major investments in public health infrastructure and primary eye care services have built a strong foundation for preventing future corneal blindness. However, there are an estimated 4.9 million bilaterally corneal blind persons worldwide who could potentially have their sight restored through corneal transplantation. Traditionally, barriers to increased corneal transplantation have been daunting, with limited tissue availability and lack of trained corneal surgeons making widespread keratoplasty services cost prohibitive and logistically unfeasible. The ascendancy of cataract surgical rates and more robust eye care infrastructure of several Asian and African countries now provide a solid base from which to dramatically expand corneal transplantation rates. India emerges as a clear global priority as it has the world's largest corneal blind population and strong infrastructural readiness to rapidly scale its keratoplasty numbers. Technological modernization of the eye bank infrastructure must follow suit. Two key factors are the development of professional eye bank managers and the establishment of Hospital Cornea Recovery Programs. Recent adaptation of these modern eye banking models in India have led to corresponding high growth rates in the procurement of transplantable tissues, improved utilization rates, operating efficiency realization, and increased financial sustainability. The widespread adaptation of lamellar keratoplasty techniques also holds promise to improve corneal transplant success rates. The global ophthalmic community is now poised to scale up widespread access to corneal transplantation to meet the needs of the millions who are currently blind.
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Purpose: Limited knowledge exists about the influence of donor age and death-to-preservation interval (DPI) on the metabolic properties of the cornea. The aim of this study is to investigate the relationship between both factors and metabolite content of the cornea. Methods: Corneas from 15 human donors (age: 41–78 years) were obtained within 16 hrs post-mortem and kept in cold storage for 8 days. The metabolic profiles of the samples were investigated using high-resolution, magic angle spinning 1H nuclear magnetic resonance spectroscopy before and after 8 days of preservation. Results: Twenty-two metabolites were detected and assigned in the corneal spectra. The significant metabolic differences before and after hypothermic storage were revealed between younger and older donors. DPI-related significant differences revealed before preservation of the corneas were not displayed after 8 days of cold storage. Conclusions: Age of donor as well as post-mortem time influences the biochemical properties of the cornea. Cold storage decreases the metabolite differences between the tissues collected at different post-mortem time.
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We performed wide-field specular microscopy and pachymetry on 92 donor corneas to evaluate the changes occurring in the endothelium during moist chamber storage of up to 48 hours. Endothelial changes were quantitated with computer-assisted morphometry. The donor corneas were divided into two groups: younger (mean age, 34 years) and older (mean age, 72 years). No significant differences in endothelial cell density, coefficient of variation in cell area (polymegethism), percentage of hexagonal cells (pleomorphism), or central corneal thickness were noted between younger and older donors when storage intervals were similar. Within each group, while endothelial cell density remained constant, a marked increase in polymegethism and pleomorphism developed when storage was prolonged beyond 12 hours. Corneal thickness also increased, but there was no correlation between thickness and the extent of the endothelial changes. These results suggest that specular microscopy is a more reliable method of screening donor tissue than donor age or corneal thickness.
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The endothelial cell count was studied in 275 normal eyes. It showed a gradual decline to the age of 50 but no appreciable difference thereafter. Review of earlier reports of progressive reduction throughout life indicates that a different interpretation is likely, which conforms with the results of this and other recent studies. The value of detailed endothelial studies is discussed briefly.
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To describe corneal endothelial cell density and morphology in the Indian population and to compare endothelial cell characteristics in the Indian population with data available in literature for American and Japanese populations. Specular microscopy and corneal pachymetry were performed in both eyes of 537 normal Indian volunteers, aged 20-87 years. Parameters studied included endothelial cell density, cell area, coefficient of variation (CV) in cell area and hexagonality. Mean endothelial cell density in the study population was 2,525 +/- 337 cells/mm2. There was a statistically significant decrease in endothelial cell density with age (p < 0.001, correlation -0.387) and the rate of cell loss was 0.3% per year. There was also a statistically significant increase in mean cell area (p < 0.001, correlation 0.362) and CV (p = 0.02, correlation 0.096), and decrease in percentage of hexagonal cells (p = 0.01, correlation -0.127) with increasing age. There was no significant difference in these parameters between fellow eyes of subjects. In all age groups, the mean endothelial cell density was significantly lower than values reported previously in the Japanese population. The values were less than those described in the American population, but the differences were statistically significant only in the 20-30 and 41-50 year age groups. Normative data for the endothelium in the Indian population are reported. Endothelial cell density in Indian eyes is less than the values described in the Japanese and American populations.
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To define a behavioral model of corneal endothelial density over a lifetime, determine its values, construct a graphic representation, and show the probabilities of occurrence using modified prognosis ranges. A private clinic in Brazil. This retrospective study comprised 784 corneal specular microscopy examinations without regard to race, sex, or age and without a history or pathologies that would alter the endothelium. Endothelial density results were grouped by decades according to patient age. Projections of mean densities and standard deviations by decade were calculated by adjusting the model by variable. The probability of occurrence of the endothelial densities was calculated (P <.05). The endothelial density over time followed a decreasing linear model (correlation coefficient -0.993). As the endothelial density decreased, the standard deviation tended to increase. The probability of occurrence of an endothelial density of less than 2000 cells/mm(2) was higher from the seventh decade on. Knowing the representative values of endothelial density and the probabilities of occurrence over a lifetime can help surgeons determine the risk to the cornea of anterior segment surgery. It can also be useful in following eyes with disease affecting the endothelium and in preparing and evaluating corneal specular microscopy reports.
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To compare the endothelial and clinical outcome of penetrating keratoplasty with corneas stored in organ culture for up to 12 days (5-12 days; group 1) or more than 21 days (21-24 days; group 2). We conducted a controlled double-masked trial. Storage durations were randomly assigned to the paired corneas, and endothelial cell density (ECD) was measured at the start and end of organ culture. Patients with a low rejection risk and preoperative ECD within the reference range were randomly assigned to 1 of the 2 groups and underwent an 8.25-mm penetrating keratoplasty (n = 25 pairs). Follow-up at day 5 and months 1, 6, and 12 included central ECD, morphometry, graft transparency, visual acuity, pachymetry, and complications. The main outcome measure was the central ECD at month 12. At the end of organ culture, ECD of the group 1 corneas was higher by 273 cells/mm2 (95% confidence interval [CI], 178-368; P<.001). One year after penetrating keratoplasty, the group 1 ECD was still comparably higher by 227 cells/mm2 (95% CI, 43-411; P =.02). Graft transparency, pachymetry, and complication rate did not differ at any time. In group 1, visual acuity was better at month 1. Shorter organ culture allows delivery of corneas with higher ECD. Recipients with ECD within the reference range and low rejection risk retain this initial benefit 1 year postoperatively. The higher endothelial cell capital may prevent or delay late endothelial failure, the leading cause of graft failure in these recipients. We therefore prefer short-term storage for such recipients.