PURPOSE: The aim of our presentation is to introduce future eye bank product - corneal stromal lenticule from living donors, which can be used for allotransplantation. METHODS: ReLEx (refractive lenticule extraction) SMILE (small incision lenticule extraction) is a common approach in laser eye surgery. It is minimally invasive and flap-free procedure. During this procedure part of corneal stroma (lenticule) is created by femtosecond laser and consequently removed through small incision. The lenticule is basically waste material of the ReLEx SMILE procedure. In the International Eye Bank of Prague, we decided to establish new protocol for lenticule withdrawal, storage and release for transplantation. RESULTS: All donors signed an informed consent, and their serum was tested for the presence of infectious diseases. After ReLEx SMILE procedure the lenticule was stored in container with cryopreservation solution and frozen in the eye bank using the same protocol for frozen amniotic membrane. After 6 months in -80°C tissues were defrosted and examined histologically, using conventional light histology staining and electron microscopy. CONCLUSION: We believe, that lenticule from living donor is a safe and effective tissue, that can be used for many indications and in particular situations represents good alternative to whole donor cornea and amniotic membrane.
- MeSH
- lidé MeSH
- oční banky * MeSH
- rohovka MeSH
- stroma rohovky * chirurgie MeSH
- usmívání se MeSH
- žijící dárci MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSE: The goal of our study is to find an optimal approach to the preparation and preservation of corneal stromal tissue. We want to compare different methods of corneal stromal tissue creation and storage to optimize the efficacy of this process under the conditions of an eye bank. After we find the most suitable method to create a safe high quality product, we want to prove the possibility of using a single donor cornea for more than one patient. We would also like to verify the feasibility of making more corneal lenticules after the removal of a corneal endothelium for DMEK transplantation. METHODS: We provided morphological (histology, scanning electron microscope) and microbiological analysis in order to compare different methods of corneal lenticule and corneal stromal lamellae preparation and preservation. We also tested the surgical handling of the tissue to secure a safe manipulation of the tissue for clinical use. We compared two methods of corneal lenticule preparation: microkeratome dissection and femtosecond laser. As methods of preservation, we tested hypothermia, cryopreservation at -80 degrees Celsius in DMSO (dimethyl sulfoxide) and storage at room temperature with glycerol. Some intrastromal lenticules and lamellae in each group were previously irradiated with gamma radiation of 25 kGy (KiloGray). RESULTS: Corneal stromal lamellae prepared with a microkeratome have a smoother cut - side surface compared to lamellae prepared with a femtosecond laser. Femtosecond laser preparation caused more irregularities on the surface and we detected more conglomerates of the fibrils, while lamellae made with microkeratome had more sparse network. Using femtosecond laser, we were able to make more than five lenticules from a single donor cornea. Gamma irradiation led to damage of collagen fibrils in corneal stroma and a loss of their regular arrangement. Corneal tissue stored in glycerol showed collagen fibril aggregates and empty spaces between fibrils caused by dehydration. Cryopreserved tissue without previous gamma irradiation showed the most regular structure of the fibrils comparable to storage in hypothermia. CONCLUSION: Our results suggest that formation of a corneal lenticule lamellae by microkeratome results in smoother corneal lenticules, while being much cheaper than formation by femtosecond laser. Gamma irradiation of 25 kGy caused damage of the collagen fibres as well as their network arrangement, which correlated with loss of transparency and stiffer structure. These changes impair possible surgical utilisation of gamma irradiated corneas. Storage in glycerol at room temperature and cryopreservation had similar outcomes and we believe that both methods are appropriate and safe for further clinical use .
- MeSH
- dimethylsulfoxid MeSH
- glycerol * MeSH
- hypotermie * MeSH
- kolagen MeSH
- lidé MeSH
- rohovka chirurgie MeSH
- stroma rohovky chirurgie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSE: To evaluate changes in corneal refractive parameters after implantation of a stromal lenticule of different thickness. We assume that the refractive outcome depends on the optical power of the used lenticule. METHODS: We conducted an ex-vivo non-human study on 33 normotonic porcine eyeballs divided into two groups, for 4D and 8D human lenticule implantation. Corneal stromal lenticules were obtained as a by-product from a laser procedure ReLEx SMILE. We evaluated corneal refractive parameters measured on Oculus Pentacam© device before and immediately after the intrastromal lenticule implantation. RESULTS: There was no statistically significant difference in corneal refractive parameters between the eyeball groups before lenticule implantation. In both groups, the intrastromal implantation in the depth of 300um led to a significant increase of central corneal pachymetry and corneal anterior steepening. In the 4D group the average central corneal pachymetry increased from 903 ± 124.59 to 1230 ± 148.99 (p = 0.0022) and in 8D group from 733.35 ± 69.60 to 1109 ± 161.64 (p = 0.0008). Induced changes in other studied parameters were not statistically significant, Kmax changed from 45.57 ± 2.78 to 72.07 ± 16.83 (p = 0.0094) and Km front from 40.72 ± 1.60 to 48.87 ± 5.83 (p = 0.0037) in 4D group and in the 8D group average Kmax increased from 42.22 ± 1.54 to 62.95 ± 12.67 (p = 0.0001) and K2 front 40.46 ± 1.64 to 51.51 ± 9.63 (p = 0.0037). There were no significant differences in refractive changes between the 4D and 8D groups after lenticule implantation. CONCLUSION: Intrastromal corneal lenticule implantation induces changes in corneal refractive parameters. In both groups, the implantation induced a significant increase of an anterior corneal steepening without any significant influence on posterior corneal flattening. Corneal lenticule implantation did not lead to any significant change of corneal astigmatism. However, in order to have more precise data for future clinical applications we need to continue with the experiments and verify the results on human corneas.
- MeSH
- laserová chirurgie rohovky * metody MeSH
- lasery excimerové terapeutické užití MeSH
- lidé MeSH
- nemoci rohovky * MeSH
- prasata MeSH
- refrakce oka MeSH
- rohovka MeSH
- rohovková topografie MeSH
- stroma rohovky chirurgie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSE: To characterise the phenotype and genotype of concurrent keratoconus and Fuchs endothelial corneal dystrophy (KC + FECD). METHODS: We recruited 20 patients with concurrent KC + FECD for a retrospective observational case series from the United Kingdom and the Czech Republic. We compared eight parameters of corneal shape (Pentacam, Oculus) with two groups of age-matched controls who had either isolated keratoconus (KC) or isolated FECD. We genotyped probands for an intronic triplet TCF4 repeat expansion (CTG18.1) and the ZEB1 variant c.1920G >T p.(Gln640His). RESULTS: The median age at diagnosis of patients with KC + FECD was 54 (interquartile range 46 to 66) years, with no evidence of KC progression (median follow-up 84 months, range 12 to 120 months). The mean (standard deviation (SD)) of the minimum corneal thickness, 493 (62.7) μm, was greater than eyes with KC, 458 (51.1) μm, but less than eyes with FECD, 590 (55.6) μm. Seven other parameters of corneal shape were more like KC than FECD. Seven (35%) probands with KC + FECD had a TCF4 repeat expansion of ≥50 compared to five controls with isolated FECD. The average of the largest TCF4 expansion in cases with KC + FECD (46 repeats, SD 36 repeats) was similar to the age-matched controls with isolated FECD (36 repeats, SD 28 repeats; p = 0.299). No patient with KC + FECD harboured the ZEB1 variant. CONCLUSIONS: The KC + FECD phenotype is consistent with KC but with superimposed stromal swelling from endothelial disease. The proportion of cases with a TCF4 expansion is similar in concurrent KC + FECD and age-matched controls with isolated FECD.
- MeSH
- fenotyp MeSH
- Fuchsova endoteliální dystrofie * komplikace diagnóza genetika MeSH
- genotyp MeSH
- keratokonus * komplikace diagnóza genetika MeSH
- lidé MeSH
- retrospektivní studie MeSH
- transkripční faktor 4 genetika MeSH
- transkripční faktory BHLH-Zip genetika MeSH
- transkripční faktory genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
AIM: To determine the influence of gaps [places where neither the donor's nor the recipient's Descemet's membrane (DM) is present] and overlaps (places where the recipient's DM is covered by the donor's DM) on the frequency of postoperative detachment of DM endothelial keratoplasty (DMEK) lamellae. METHODS: Totally 64 eyes of 64 patients with Fuchs' endothelial dystrophy or bullous keratopathy indicated for DMEK were randomly divided in two groups. The diameter of the implanted DMEK lamella was the same in both groups (8 mm), but we changed the diameter of the removed recipient DM. In the first group (32 eyes), the circular area was approximately 8.5 mm (gaps); in the second group (32 eyes), the diameter was 7.5 mm (overlaps). Postoperatively we noted all cases of detachment visible on the slit lamp and these cases we indicated for rebubbling. We also measured the uncorrected distance visual acuity (UDVA) as well as corrected distance visual acuity (CDVA) in decimal and postoperative endothelial cell density (ECD). The minimum follow-up time was 6mo. RESULTS: The number of rebubbling procedures in the entire group of patients was 13, i.e., 20.3%, with 6 eyes (18.7%) in the gap group, and 7 eyes (21.9%) in the overlap group. Lamella replacement (re-DMEK) was required in 3 (gap group) and 2 patients (overlap group), respectively. The difference between the groups was statistically insignificant. The UDVA was 0.54±0.21 in the gap group and 0.58±0.24 in the overlap group. The CDVA was 0.74±0.22 and 0.80±0.16, respectively. ECD was 1920±491 and 2149±570 cells/mm2. The small differences between both groups were not statistically significant. CONCLUSION: We do not notice any difference in the group of patients with overlaps or gaps of DM. The presence of small areas of gaps or overlaps does not affect the frequency of detachment of the DMEK lamellae.
- Publikační typ
- časopisecké články MeSH
Cíle: Zhodnocení výsledků zadních lamelárních keratoplastik typu DMEK a PDEK na fakických očích. Materiál a metody: Retrospektivní analýza operací, které byly provedeny na našem pracovišti v období od června 2016 do prosince 2019. V hodnocení jsme se zaměřili na pooperační zrakovou ostrost, počet endotelových buněk na mm2 a možné peroperační i pooperační komplikace včetně rozvoje komplikované katarakty. Výsledky: Bylo provedeno 12 operací na 11 očích u 7 pacientů. Z primárních diagnóz převažovala Fuchsova endotelová dystrofie (7 očí), dále jsme zaznamenali bulózní keratopatii po implantaci fakické předněkomorové IOL (2 oči) a iridokorneální endotelový syndrom (2 oči). Průměrná délka sledování byla 12,5 měsíců. K rozvoji a následné operaci komplikované katarakty během roku sledování došlo u 3 očí, jedenkrát byl nutný rebubbling pro nevhodnou polohu a jedenkrát rePDEK pro dysfunkci lamely. Na konci sledování dosáhla průměrná nejlepší korigovaná zraková ostrost hodnoty 0,87, přičemž 82 % očí dosáhlo nejlepší korigované zrakové ostrosti 0,8 nebo lepší, a průměrný počet endotelových buněk hodnoty 1589 buněk/mm2. Závěr: Zadní lamelární keratoplastiky typu DMEK a PDEK lze provádět i na fakických očích. V rukách zkušeného chirurga se jedná o bezpečné výkony s dobrými pooperačními výsledky, které navíc u mladších pacientů umožňují zachovat schopnost akomodace.
Purpose: To evaluate the results of posterior lamellar keratoplasties (DMEK and PDEK) in phakic eyes. Material and methods: Retrospective analysis of surgeries performed in our department between June 2016 and December 2019. The main focus was put on postoperative visual acuity, corneal endothelial cell density and possible peroperative and postoperative complications including cataract formation. Results: We performed 12 surgeries on 11 eyes of 7 patients. The most prevalent primary diagnosis was Fuchs’ endothelial dystrophy (7 eyes), followed by bullous keratopathy after phakic anterior chamber IOL implantation (2 eyes) and ICE syndrome (2 eyes). The average length of follow-up was 12.5 months. Clinically significant complicated cataract had developed and was removed in 3 eyes, one eye required rebubbling due to graft detachment and one eye required rePDEK due to graft failure. At the end of follow-up, the average visual acuity was 0.87, while 82% of eyes achieved VA 0.8 or better, and the average endothelial cell density was 1589 cells/mm2. Conclusion: Posterior lamellar keratoplasties (DMEK and PDEK) can be performed on phakic eyes. When performed by an experienced surgeon, these are safe procedures with good postoperative results and significant advantage in preserving younger patients’ accommodation.
- MeSH
- Descemetova membrána chirurgie MeSH
- fakické nitrooční čočky * MeSH
- lidé středního věku MeSH
- lidé MeSH
- nemoci rohovky chirurgie MeSH
- počet buněk MeSH
- retrospektivní studie MeSH
- rohovkový endotel MeSH
- zadní lamelární keratoplastika * metody MeSH
- zraková ostrost MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
Diabetická retinopatie (DR) je jednou z nejčastějších příčin poklesu zrakové ostrosti ve vyspělých zemích, a to především změnou životního stylu. Její zvládnutí je založeno na prevenci, optimální kompenzaci diabetu, ale i dalších rizikových faktorů. Současná léčba počítá s laserovou terapií, aplikací intravitreálních anti-VEGF látek či kortikosteroidů a pars plana vitrektomií. Farmakoterapie se, až na malé výjimky, ukazuje jako málo účinná. Článek se zabývá kontroverzemi a novými poznatky o léčbě DR hypolipidemiky. Upozorňuje na nelipidový mechanismus účinku fibrátu na DR. Článek je doprovázen dvěma kazuistikami.
Diabetic retinopathy (DR) is one of the most common causes of visual acuity impairment in developed countries, mainly due to the change of lifestyle. Its management is based on prevention, optimal diabetes control, but also other risk factors. Current treatment includes laser therapy, application of intravitreal anti-VEGF substances or corticosteroids and pars plana vitrectomy. Pharmacotherapy, with few exceptions, proves to be ineffective. The article deals with controversies and new findings about hypolipidaemic treatment of DR. It points out the possibilities of hypolipidaemic drugs affecting DR. The article is accompanied by two case reports.
- Klíčová slova
- studie FIELD, studie ACCORD,
- MeSH
- diabetes mellitus 1. typu farmakoterapie komplikace MeSH
- diabetes mellitus 2. typu farmakoterapie komplikace MeSH
- diabetická retinopatie * diagnostické zobrazování prevence a kontrola MeSH
- fenofibrát * farmakologie terapeutické užití MeSH
- klinické zkoušky jako téma MeSH
- kombinovaná farmakoterapie MeSH
- krevní tlak účinky léků MeSH
- lidé MeSH
- lipidy krev MeSH
- progrese nemoci MeSH
- statiny terapeutické užití MeSH
- Check Tag
- lidé MeSH
Corneal stromal lenticule is a part of corneal stroma, which can be created by manual dissection, by femtosecond laser from the donor cornea, but chiefly it is a waste product of a refractive procedure ReLex SMILE (Small Incision Lenticule Extraction). Corneal lenticule has a huge potential in corneal surgery. In recent years, many studies have been published to show the possibility to use this tissue to treat corneal defects, as well as in refractive surgery. Thanks to the quantity of lenticules which arise every day during SMILE operations, this tissue is much more accessible than any other kind of corneal tissue. According to the experience with lenticule implantation in animal models, or even human patients, lenticule implantation is considered safe, reversible method, which is not associated with immune rejection or other severe complications. However, the crucial step before the process of lenticule implantation, is proper preservation of this tissue. Donor corneal tissue containing endothelium is usually preserved in hypothermia and then usable maximally for two weeks. Newer methods such as organ culture storage and use of a sterile cornea prolong the time of usability of the tissue. The possibilities for corneal lenticule storage are theoretically wider thanks to the fact, that we do not need to preserve fragile cellular structures. Besides the storage in hypothermia, other preserving methods such as cryopreservation and storage after decellularization have been tested. This review aimed to examine the current literature that describes possible methods of corneal lenticule preservation. A comprehensive search was created based on articles published in English on PubMed.gov, Cochranelibrary.com and Scopus.com using following keywords: corneal lenticule preservation, corneal lenticule storage, cold storage corneal lenticule, corneal lenticule cryopreservation till 2020.
- MeSH
- hypotermie * MeSH
- kryoprezervace MeSH
- lidé MeSH
- rohovka chirurgie MeSH
- rohovkový endotel MeSH
- stroma rohovky * chirurgie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
PURPOSE: To evaluate the long-term results of combining cataract surgery, intraocular lens (IOL) implantation, and Descemet membrane endothelial keratoplasty with peripheral stromal support (DMEK-S). METHODS: The outcomes of 107 eyes of 37 patients who had undergone a combination of cataract surgery, IOL implantation, and DMEK-S between October 2007 and February 2015 were retrospectively evaluated. The average follow-up duration was 18.2 ± 18.3 months (range, 6-84 months). Changes in uncorrected and corrected distance visual acuity, spherical equivalent, and corneal endothelial cell density were analyzed. Intraoperative and postoperative complications were also recorded. RESULTS: The mean logMAR uncorrected distance visual acuity improved from 0.92 ± 0.60 preoperatively to 0.33 ± 0.33, 0.28 ± 0.25, 0.24 ± 0.20, and 0.27 ± 0.27 at 6, 12, 24, and 36 months postoperatively (P < 0.001), respectively. The mean logMAR corrected distance visual acuity improved from 0.62 ± 0.65 preoperatively to 0.17 ± 0.29, 0.13 ± 0.21, 0.07 ± 0.16, and 0.11 ± 0.23 at 6, 12, 24, and 36 months postoperatively (P < 0.001), respectively. The mean endothelial cell density decreases were 50.7% ± 21.1%, 50.8% ± 19.8%, 60.7% ± 16.6%, 62.2% ± 11.8%, and 61.8% ± 20.0% at 6, 12, 24, 36, and 48 months after surgery, respectively. Similar trends, although with slightly better visual outcomes, were found in the subgroup of patients without other eye diseases. The mean final deviation from intended spherical equivalent was 0.77 ± 1.19 D, representing a hyperopic shift. CONCLUSIONS: A combined procedure of cataract surgery, IOL implantation, and DMEK-S is an effective method of treatment in patients with combined corneal disease and cataract, maintaining visual rehabilitation in the long term. Future developments should be performed to minimize the incidence of complications.
- MeSH
- fakoemulzifikace * MeSH
- implantace nitrooční čočky MeSH
- katarakta komplikace MeSH
- lidé středního věku MeSH
- lidé MeSH
- následné studie MeSH
- nemoci rohovky komplikace MeSH
- počet buněk MeSH
- poruchy zraku rehabilitace MeSH
- retrospektivní studie MeSH
- rohovkový endotel patologie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- stroma rohovky chirurgie MeSH
- úbytek endoteliálních buněk rohovky patofyziologie MeSH
- výsledek terapie MeSH
- zadní lamelární keratoplastika * MeSH
- zraková ostrost fyziologie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
PURPOSE: To determine the frequency of formation of various types of bubbles and the potential impact of donor and lamella parameters on this frequency, and to identify possible risk factors of unsuccessful "big-bubble" creation in preparation of pre-Descemet endothelial keratoplasty and Descemet membrane endothelial keratoplasty with peripheral stromal support. METHODS: Donor age and sex, death to preservation time (DPT), storage time, presence of corneal scars (mainly a condition after cataract surgery), and endothelial cell density of 256 donor corneas were assessed before Descemet membrane endothelial keratoplasty with peripheral stromal support or pre-Descemet endothelial keratoplasty lamella preparation using the big-bubble technique. RESULTS: Mean donor age was 62.3 ± 8.5 years (28.3% women and 71.7% men). Mean endothelial cell density of the donor graft was 2866 ± 255 cells/mm. Mean DPT was 10.12 ± 4.88 hours, and mean storage time of the transplant before surgery was 6.5 ± 4.8 days. Corneal scars were present in 17 donor grafts (6.6%) after cataract surgery. Eleven corneas were devalued because of Descemet membrane rupture during preparation (4.3%). In 182 corneas, standard bubble type I was created (71.7%); in 27 corneas, bubble type II was created; eventually, both types of bubbles formed simultaneously (10.5%); in 47 corneas, no bubble was created (18.4%). CONCLUSIONS: We identified higher endothelial cell density, shorter DPT, and the presence of corneal scars after cataract surgery as risk factors threatening successful bubble formation. The only risk factor for creating type II bubbles was higher donor age in our study.
- MeSH
- časové faktory MeSH
- Descemetova membrána chirurgie MeSH
- disekce metody MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- nemoci rohovky chirurgie MeSH
- peroperační komplikace MeSH
- prospektivní studie MeSH
- rizikové faktory MeSH
- rohovkový endotel cytologie MeSH
- senioři MeSH
- uchovávání tkání statistika a číselné údaje MeSH
- zadní lamelární keratoplastika metody MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH