Bjoern O Bachmann

Universitätsklinikum Erlangen, Erlangen, Bavaria, Germany

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Publications (40)128.52 Total impact

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    ABSTRACT: To reinvestigate the ultrastructure of the posterior stroma of the human cornea and to correlate the findings with the stromal behavior after big-bubble creation. Observational consecutive 3-center case series. Fresh corneoscleral buttons from human donors (n = 19) and organ-cultured corneoscleral buttons (n = 10) obtained after Descemet's membrane endothelial keratoplasty. Corneal specimens were divided into central (3 mm), mid peripheral (8 mm), and peripheral parts by trephination and processed for transmission electron microscopic and immunohistochemical analyses. A big bubble was created by air injection into the stroma of organ-cultured corneas before fixation. The distance of keratocytes to Descemet's membrane, number of collagen lamellae between keratocytes and Descemet's membrane, diameter and arrangement of collagen fibrils, thickness of stromal lamella created by air injection, and immunopositivity for collagen types III, IV, and VI. Stromal keratocytes were observed at variable distances from Descemet's membrane, increasing from 1.5 to 12 μm (mean, 4.97±2.19 μm) in the central, 3.5 to 14 μm (mean, 8.03±2.47 μm) in the midperipheral, and 4.5 to 18 μm (mean, 9.77±2.90 μm) in the peripheral regions. The differences in mean distances were significant (P < 0.0001). The number of collagen lamellae between Descemet's membrane and most posterior keratocytes varied from 2 to 10 and the diameter of collagen fibrils averaged 23.5±1.8 nm and corresponded with that of the remaining stroma. A thin layer (0.5-1.0 μm thick) of randomly arranged, unaligned collagen fibers, which was positive for collagen types III and VI, was observed at the Descemet-stroma interface. The residual stromal sheet separated by air injection in 8 of 10 donor corneas varied in thickness from 4.5 to 27.5 μm, even within individual corneas (≤3-fold), and was composed of 5 to 11 collagen lamellae that revealed keratocytes on their anterior surface and in between. Barring an anchoring zone of interwoven collagen fibers at the Descemet-stroma interface, the findings did not provide any evidence for the existence of a distinctive acellular pre-Descemet's stromal layer in the human cornea. The intrastromal cleavage plane after pneumodissection seems to be nonreproducibly determined by the intraindividually and interindividually variable distances of keratocytes to Descemet's membrane. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.
    Ophthalmology 11/2014; · 5.56 Impact Factor
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    ABSTRACT: Purpose To characterize the alterations of extracellular matrix proteins in Descemet's membranes (DM) of patients with late-onset Fuchs corneal dystrophy (FCD) and to differentiate them from unspecific alterations in pseudophakic bullous keratopathy (PBK). Methods Human Descemet's membrane/endothelial cell complexes were obtained from patients with late onset FCD (n=40), PBK (n=6), and control eyes (n=5). Gene expression profiles of endothelial cells were compared using a commercial real-time-PCR array and quantitative real-time-PCR assays for confirmation of differentially expressed genes. A total of 24 extracellular matrix proteins were also localized in cryosections of corneal specimens from FCD (n=10), PBK (n=4) and control eyes (n=5) by immunohistochemistry. Results PCR array analysis revealed a significant upregulation of 27 out of 84 extracellular matrix related genes including collagens, proteoglycans, glycoproteins, cell adhesion molecules, and matrix metalloproteinases in FCD specimens as compared to normal controls, which could be partly confirmed and quantified by real-time PCR. Comparative analysis of FCD and PBK specimens showed a significant and consistent FCD-specific upregulation of collagen type I, III, and XVI, fibronectin, agrin, clusterin, transforming growth factor beta-induced (TGFBI), and integrin α4 (3-18 fold, p<0.05). Immunohistochemistry revealed an increased labelling of collagen type III, VII, XV, XVI, agrin, fibulin-2, TGFBI, versican, and clusterin in the DM of FCD specimens compared to PBK specimens. Conclusions The findings provide evidence for a specific upregulation, production and deposition of collagen type III and XVI, agrin, TGFBI, and clusterin in late-onset FCD and thus point to the importance of matrix alterations in the pathophysiology of FCD.
    Investigative ophthalmology & visual science 05/2014; · 3.43 Impact Factor
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    ABSTRACT: Eye drops of aganirsen, an antisense oligonucleotide preventing insulin receptor substrate-1 expression, inhibited corneal neovascularization in a previous dose-finding phase II study. We aimed to confirm these results in a phase III study and investigated a potential clinical benefit on visual acuity (VA), quality of life (QoL), and need for transplantation. Multicenter, double-masked, randomized, placebo-controlled phase III study. Analysis of 69 patients with keratitis-related progressive corneal neovascularization randomized to aganirsen (34 patients) or placebo (35 patients). Patients applied aganirsen eye drops (86 μg/day/eye) or placebo twice daily for 90 days and were followed up to day 180. The primary end point was VA. Secondary end points included area of pathologic corneal neovascularization, need for transplantation, risk of graft rejection, and QoL. Although no significant differences in VA scores between groups were observed, aganirsen significantly reduced the relative corneal neovascularization area after 90 days by 26.20% (P = 0.014). This improvement persisted after 180 days (26.67%, P = 0.012). Aganirsen tended to lower the transplantation need in the intent-to-treat (ITT) population at day 180 (P = 0.087). In patients with viral keratitis and central neovascularization, a significant reduction in transplantation need was achieved (P = 0.048). No significant differences between groups were observed in the risk of graft rejection. However, aganirsen tended to decrease this risk in patients with traumatic/viral keratitis (P = 0.162) at day 90. The QoL analyses revealed a significant improvement with aganirsen in composite and near activity subscores (P = 0.039 and 0.026, respectively) at day 90 in the per protocol population. Ocular and treatment-related treatment-emergent adverse events (TEAEs) were reported in a lower percentage with aganirsen compared with placebo. Only 3 serious TEAEs (2 with aganirsen and 1 with placebo) were considered treatment-related. This first phase III study on a topical inhibitor of corneal angiogenesis showed that aganirsen eye drops significantly inhibited corneal neovascularization in patients with keratitis. The need for transplantation was significantly reduced in patients with viral keratitis and central neovascularization. Topical application of aganirsen was safe and well tolerated.
    Ophthalmology 05/2014; · 5.56 Impact Factor
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    ABSTRACT: No standardized biomaterial exists for the surgical treatment of persistent corneal erosions and ulcerations. We analyzed the suitability and biocompatibility of defined non-crosslinked and UV/riboflavin crosslinked equine type I collagen membranes for the reconstruction of the corneal surface. Isolated human oral mucosa epithelial cells, a cell type in clinical use for the treatment of ocular surface diseases, were subcultivated on both types of membranes and examined concerning cell adhesion, proliferation and differentiation. Biocompatibility was evaluated following superficial and intrastromal corneal transplantation in New Zealand white rabbits. In cell cultures all collagen membranes supported adhesion of oral mucosa epithelial cells leading to the formation of multilayered epithelial cell sheets. After intrastromal corneal implantation clinical signs of degradation were seen in all variants of collagen membranes, which was fastest in non-crosslinked variants. On the histological and ultrastructural level invasion of keratocytes and production of new collagen fibers inside the collagen membranes could be detected in non-crosslinked variants. After superficial corneal implantation covering of the membranes by corneal epithelium over time was visible. Ultrastructural analysis showed a slower rate of degradation and less invading keratocytes in crosslinked variants compared to non-crosslinked collagen membranes. Crosslinked as well as non-crosslinked variants of the collagen membrane proofed to be suitable to serve as a carrier for epithelial stem cells in-vitro and showed a high biocompatibility in-vivo. These results indicate that the tested collagen membranes might be suitable for the reconstruction of the corneal surface in patients with non-healing ulcerations. Whether membranes with faster or slower degradation properties are preferable for the treatment of persistent corneal ulcerations might depend on the underlying corneal pathology and the degree of concomitant inflammation.
    Tissue Engineering Part A 03/2014; · 4.64 Impact Factor
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    ABSTRACT: Objective Eye drops of aganirsen, an antisense oligonucleotide preventing insulin receptor substrate-1 expression, inhibited corneal neovascularization in a previous dose-finding phase II study. We aimed to confirm these results in a phase III study and investigated a potential clinical benefit on visual acuity (VA), quality of life (QoL), and need for transplantation. Design Multicenter, double-masked, randomized, placebo-controlled phase III study. Participants Analysis of 69 patients with keratitis-related progressive corneal neovascularization randomized to aganirsen (34 patients) or placebo (35 patients). Patients applied aganirsen eye drops (86 μg/day/eye) or placebo twice daily for 90 days and were followed up to day 180. Main Outcome Measures The primary end point was VA. Secondary end points included area of pathologic corneal neovascularization, need for transplantation, risk of graft rejection, and QoL. Results Although no significant differences in VA scores between groups were observed, aganirsen significantly reduced the relative corneal neovascularization area after 90 days by 26.20% (P = 0.014). This improvement persisted after 180 days (26.67%, P = 0.012). Aganirsen tended to lower the transplantation need in the intent-to-treat (ITT) population at day 180 (P = 0.087). In patients with viral keratitis and central neovascularization, a significant reduction in transplantation need was achieved (P = 0.048). No significant differences between groups were observed in the risk of graft rejection. However, aganirsen tended to decrease this risk in patients with traumatic/viral keratitis (P = 0.162) at day 90. The QoL analyses revealed a significant improvement with aganirsen in composite and near activity subscores (P = 0.039 and 0.026, respectively) at day 90 in the per protocol population. Ocular and treatment-related treatment-emergent adverse events (TEAEs) were reported in a lower percentage with aganirsen compared with placebo. Only 3 serious TEAEs (2 with aganirsen and 1 with placebo) were considered treatment-related. Conclusions This first phase III study on a topical inhibitor of corneal angiogenesis showed that aganirsen eye drops significantly inhibited corneal neovascularization in patients with keratitis. The need for transplantation was significantly reduced in patients with viral keratitis and central neovascularization. Topical application of aganirsen was safe and well tolerated.
    Ophthalmology 01/2014; · 5.56 Impact Factor
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    ABSTRACT: IMPORTANCE It is essential to devise strategies that improve graft adhesion after Descemet membrane endothelial keratoplasty (DMEK) to reduce the rebubbling rate. OBJECTIVE To evaluate the influence of the extent of descemetorhexis on graft adhesion properties after DMEK. DESIGN, SETTING, AND PARTICIPANTS Single-surgeon, retrospective, observational case series conducted in the Department of Ophthalmology, University of Erlangen-Nuremberg, Germany, that reviewed the medical records of 200 consecutive patients undergoing DMEK. Fifty-three eyes of 51 patients undergoing DMEK for Fuchs endothelial dystrophy fulfilling the inclusion criteria were enrolled in this study. Based on intraoperative drawings, postoperative slitlamp examination, and photographs, eyes were divided into 2 groups. The diameter of the descemetorhexis was approximately 10 mm in group A (30 eyes), resulting in a peripheral 1-mm zone of denuded stroma between the graft and the host's Descemet membrane, and approximately 6 mm in group B (23 eyes), resulting in a peripheral 1-mm zone of overlapping between the graft and the host's Descemet membrane. MAIN OUTCOMES AND MEASURES Graft detachment rate, extent of graft detachment (in clock hours of graft's circumference), and rebubbling rate. RESULTS Four days after DMEK, the graft detachment rate was 33.3% (10 of 30) in group A and 78.3% (18 of 23) in group B (P = .002). The mean (SD) extent of graft detachment was 0.6 (0.9) and 2.8 (2.5) clock hours in groups A and B, respectively (P < .001), 4 days after surgery. The rebubbling rate was 6.7% (2 of 30) and 30.4% (7 of 23) for groups A and B, respectively (P = .03). CONCLUSIONS AND RELEVANCE A larger descemetorhexis in DMEK is correlated with better graft adhesion and lower rebubbling rates. Therefore, patients with a larger descemetorhexis require less intensive follow-up.
    Jama Ophthalmology 12/2013; · 3.83 Impact Factor
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    ABSTRACT: To describe the use of an accidentally torn Descemet membrane (DM) to successfully complete Descemet membrane endothelial keratoplasty (DMEK) surgery. Retrospective, observational case series of 3 eyes of 3 patients undergoing DMEK with a DM accidentally torn into 2 pieces during graft preparation. The mean outcome measures included best-corrected visual acuity, endothelial cell density, and central corneal thickness, before and at 1, 3, and 6 months after the DMEK surgery was performed. During graft preparation, immediately before transplantation, a large tear within the 8.0-mm marking line of the DM occurred, resulting in a DM torn into 2 pieces. In all the eyes, both pieces were successfully implanted into the anterior chamber, unfolded and attached to the posterior corneal stroma, one after the other. Six months after the surgery was performed, the best-corrected visual acuity ranged between 20/30 and 20/25. Endothelial cell loss was about 30% (range 28%-32%) 6 months after the surgery. Pachymetry findings showed normal corneal thickness 6 months after the surgery. All corneas remained clear without any signs of graft failure within 6 months of follow-up. DMEK surgery can be successfully completed despite the accidental tearing of donor DMs during the preparation of DMEK grafts by the sequential implantation of both DM pieces.
    Cornea 09/2013; · 1.75 Impact Factor
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    ABSTRACT: To assess the reproducibility of manual graft preparation and evaluate the incidence rate and nature of structural anomalies of Descemet's membrane (DM) preventing successful graft preparation in DM endothelial keratoplasty (DMEK). Prospective, single-center, nonrandomized, consecutive case series. We analyzed 350 corneoscleral buttons from donors aged 18-95 years stored in Optisol-GS or Dulbecco's modified Eagle's medium and used for DMEK surgery in 343 consecutive patients with Fuchs' endothelial dystrophy or pseudophakic bullous keratopathy. Residual endothelial cell-DM complexes obtained after successful DM stripping for DMEK and whole donor corneas obtained after unsuccessful DM stripping were examined by transmission electron microscopy and immunohistochemistry. Accuracy of the cleavage plane between DM and corneal stroma and structural abnormalities of the DM-stroma interface. Uneventful manual separation without any disruption of DM was achieved in 335 of 350 donor corneas (95.7%) by use of a previously established bimanual submerged preparation technique. Correspondingly, the peeled DM specimens revealed a regular and smooth cleavage plane exposing the amorphous interfacial matrix on their anterior surface. Although 8 of 350 donor corneas (2.3%) showed focal adhesions of DM to the corneal stroma and developed isolated tears during stripping, preparation of the graft could be successfully completed. However, 7 of the 350 donor corneas (2.0%) showed extremely strong adhesion and multiple tears of DM, preventing successful preparation of the graft. These specimens revealed either ultrastructural (peg-like interlockings) or biochemical abnormalities (increased staining intensities for adhesive glycoproteins) along the DM-stroma interface. Using an appropriate technique, manual preparation of grafts for DMEK with reproducible tissue qualities is possible in the vast majority (98%) of donor corneas. Although a relatively rare phenomenon, interindividual variations in DM structure and composition may be responsible for failure of graft preparation in about 2% of donor corneas. The authors have no proprietary or commercial interest in any of the materials discussed in this article.
    Ophthalmology 07/2013; · 5.56 Impact Factor
  • C Cursiefen, B Bachmann
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    ABSTRACT: PURPOSE: The aim was to demonstrate the feasibility of targeted removal of a central visually disturbing roll in Descemet's membrane after complicated cataract surgery. MATERIALS AND METHODS: Case report: a 76-year-old patient complained of halos and reduced visual acuity after external cataract surgery. At slit-lamp examination a central roll in Descemet's membrane was found (2 × 2 mm). RESULTS: A targeted central descemetectomy was performed by circular descemetorhexis around the defect. Early postoperative visual acuity improved and halos disappeared. At 2 months postoperatively best corrected visual acuity (BCVA) was 1.0 and the endothelial cell count was not significantly changed. CONCLUSIONS: Central targeted descemetorhexis is a safe therapeutic option for visually disturbing defects of Descemet's membrane.
    Der Ophthalmologe 02/2013; · 0.53 Impact Factor
  • C. Cursiefen, B. Bachmann
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    ABSTRACT: Die gezielte Entfernung der zentralen Descemet als Therapieoption bei iatrogener visuslimitierender zentraler Descemet-Rolle wird dargestellt.Ein 76-jähriger Patient stellte sich mit Visusminderung und Halos nach externer Kataraktoperation vor. Spaltlampenmikroskopisch fand sich eine zentrale Descemet-Rolle (2 × 2 mm).Im Rahmen einer geplanten Descemetektomie wurde die zentrale Descemet-Rolle im Sinne einer Descemetorhexis mit der Unterwasserpinzette entfernt. Unmittelbar postoperativ besserten sich die Halobeschwerden. Zwei Monate postoperativ lag der bestkorrigierter Visus (BCVA) bei 1,0, die zentrale Hornhaut war glatt und klar, und die Endothelzellzahl hatte sich zentral nicht signifikant vermindert.Die zentrale Descemetorhexis stellt eine Therapieoption bei zentralen Descemet-Defekten mit subjektiven Beschwerden dar. Bei gesundem Hornhautendothel kommt es zu einer komplikationslosen Wundheilung.
    Der Ophthalmologe 01/2013; 110(9). · 0.53 Impact Factor
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    ABSTRACT: A 39-year-old male patient underwent uncomplicated deep anterior lamellar keratoplasty due to keratoconus. On day 5 after surgery, small whitish infiltrates developed in the corneal interface. The diagnosis of fungal keratitis was made when the culture medium of the graft grew Candida after the surgical intervention. Despite intensive antimycotic treatment and irrigation of the interface, the infiltrates persisted and eventually enlarged. Therefore, revision surgery with penetrating keratoplasty was performed. Microbiological analysis showed Candida orthopsilosis in the culture of the excised graft button. Histopathological staining of the excised graft showed periodic acid-Schiff-positive and Grocott methenamine silver-positive clusters of yeast between Descemet's membrane and the deep corneal stroma with focal perforations through Descemet's membrane. The treatment of mycotic keratitis caused by C orthopsilosis is challenging. Antimycotic treatment was unsuccessful in this case. Progression of the keratitis and perforation of Descemet's membrane suggest that early surgical intervention by penetrating keratoplasty is required.
    Case Reports 01/2013; 2013.
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    ABSTRACT: To evaluate the functional and morphologic outcome of Descemet membrane endothelial keratoplasty (DMEK) combined with phacoemulsification and intraocular lens implantation in patients suffering from endothelial dysfunction and cataract. Retrospective, single-center, consecutive case series. Triple-DMEK (DMEK with simultaneous cataract surgery) was performed in 61 consecutive eyes of 56 patients using corneal donor tissue pre-stored in either short-term culture (Optisol-GS) at 4 C or organ culture (Dulbecco's modified Eagle's medium, CorneaMax medium) at 34 C. Main outcome measures included the number of air injections necessary for graft attachment as well as best-corrected visual acuity (BCVA [logMAR]), central corneal thickness (CCT), endothelial cell density (ECD), refractive spherical equivalent, refractive cylinder, and topographic cylinder at 1, 3, and 6 months postoperatively. BCVA increased from 0.6 ± 0.23 logMAR preoperatively (n = 54) to 0.19 ± 0.22 logMAR at 6 months (n = 27) after surgery (P ≤ .05). ECD of donor corneas decreased from 2573 ± 235 cells/mm(2) (n = 61) to 1550 ± 326 cells/mm(2) (n = 29) after 6 months (P ≤ .05). CCT decreased from 651 ± 69 μm (n = 54) preoperatively to 521 ± 65 μm (n = 27) after 6 months (P ≤ .05). Refractive spherical equivalent was -0.3 ± 2.8 D (n = 27) preoperatively and 0.9 ± 1.5 D 6 months (n = 27) after surgery. A total of 54.5% of eyes were within 1 D of emmetropia (n = 12) and 77.3% were within 2 D of emmetropia (n = 17) 6 months (n = 22) after surgery. Refractive cylinder was -0.9 ± 1.0 D preoperatively (n = 49) and -1.5 ± 1.0 D 6 months (n = 23) after surgery. The change in refractive cylinder within the first month was statistically significant (P ≤ .05; Wilcoxon test). Topographic cylinder was 2.1 ± 1.7 D preoperatively (n = 58) and 1.7 ± 1.1 D 6 months (n = 28) after surgery. Between 3 and 6 months a significant change in topographic cylinder towards lower values was measured (P ≤ 0.05; Wilcoxon test). Optimized spherical results were achieved by selecting intraocular lenses based on a hyperopic shift of -0.75 D. DMEK combined with cataract surgery (triple procedure) can routinely be performed in cases of endothelial dystrophy and cataract. The addition of cataract surgery to DMEK had no adverse effect on endothelial function or graft adhesion and did not increase the likelihood of postoperative complications.
    American Journal of Ophthalmology 03/2012; 154(1):47-55.e2. · 4.02 Impact Factor
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    ABSTRACT: BACKGROUND: Postoperative complications after high-risk corneal grafting are decisively associated with corneal neovascularization (CNV). This study aimed to identify the incidence, extent, speed, localization, and influence of surgery-related factors on CNV after high-risk penetrating keratoplasty (PK) and to evaluate the effect of removing the angiogenic stimulus, i.e., residual components of herpes simplex virus (HSV) on postkeratoplasty CNV in patients with herpetic stromal keratitis (HSK). METHODS: All primary high-risk PK performed for HSK and non-herpetic keratitis (controls) between 1 January 1998 and 31 December 2003 at our department with available standardized corneal photographs taken preoperatively as well as 6 weeks, 3, 6 and 12 months postoperatively were evaluated (n (herpes) = 19, n (controls) = 5 patients). Maximal extension of CNV, limbus suture distance (LSD), limbus graft distance (LGD) and graft size in digitalized pictures were measured in each of the 16 sectors of the cornea at every visit. RESULTS: One hundred percent of the prevascularized corneas (n = 24) showed further CNV outgrowth within 1 year after keratoplasty, while 58 % of these patients featured high-grade CNV reaching the host-graft junction or invading the donor tissue. Overall, CNV outgrowth was fastest during the first 6 weeks after PK, with a mean speed of 48 μm/week. Mean CNV growth speed within 6 months post-PK was significantly lower in the herpes group (13 μm/week) than in the non-herpes group (25 μm/week, p = 0.017). Corneal location around the 12 o'clock position showed the most intense vessel outgrowth, which proved to be an independent risk factor for high-grade CNV (p = 0.025). Inverse correlation was evident between CNV growth speed and LSD (p = 0.032). CONCLUSIONS: Additional intense CNV outgrowth is a common phenomenon after high-risk keratoplasty, strongly marked in the early postoperative period. The removal of residual HSV components representing a potential angiogenic stimulus leads to a reduction in corneal angiogenesis not in the short term, but in the long term after PK in patients with HSK. In addition to preferable atraumatic operation techniques, modern antiviral prophylaxis and anti-angiogenic therapy should be applied early, possibly even prior to transplantation. Short LSD seems to be an intraoperative adjustable risk factor for CNV in high-risk setting. Attention should also be paid to the superior site around the 12 o'clock position.
    Albrecht von Graæes Archiv für Ophthalmologie 03/2012; · 1.93 Impact Factor
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    ABSTRACT: PURPOSE: To describe a new surgical technique allowing dissection down to Descemet membrane in big-bubble deep anterior lamellar keratoplasty (DALK) with failed big-bubble formation (the "microbubble incision technique"). METHODS: This is an interventional case series of 10 consecutive patients with keratoconus undergoing intended big-bubble DALK with failure to establish a normal big bubble. In all patients, repeated air injections into the stroma were performed, leaving a whitish colored stroma. Lamellar dissection as far down as possible was then performed within this white tissue. As soon as the anterior chamber was visible, a large remaining intrastromal air bubble was incised with a sharp 15-degree knife introduced perpendicular to the tissue to open up this predescemetic bubble. If deeper air bubbles were still visible, this approach was repeated. Using a blunt spatula, this new layer was then prepared and viscodissection performed. RESULTS: Using this novel approach, in 9 of the 10 patients, it was possible to dissect down to Descemet membrane. Macroperforation made conversion to penetrating keratoplasty necessary in 1 patient. Microperforations not necessitating conversion occurred in 2 patients. All 9 patients with "rescued" DALK had an uneventful postoperative course and had a mean visual acuity of 20/63 ± 20/125 (range, 20/500-20/50) and a mean endothelial cell count of 1672 ± 163 cells per square millimeter (range, 1493-1867 cells/mm) at 3 months. CONCLUSIONS: Microbubble incision is a new rescue technique for big-bubble DALK patients without bubble formation allowing for a safer dissection down to Descemet membrane.
    Cornea 03/2012; · 1.75 Impact Factor
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    ABSTRACT: To evaluate visual outcome and endothelial cell survival after Descemet membrane endothelial keratoplasty (DMEK) in comparison with Descemet stripping automated endothelial keratoplasty (DSAEK). Single-center, retrospective, consecutive case series. Thirty-eight eyes of 38 consecutive patients undergoing DMEK, who completed a 6-month follow-up, were compared with 35 eyes of 35 consecutive patients undergoing DSAEK for Fuchs endothelial dystrophy or pseudophakic bullous keratopathy. Main outcome measures included best-corrected visual acuity (in logarithm of the minimal angle of resolution [logMAR] units) and endothelial cell density within a 6-month follow-up. Best-corrected visual acuity increased from 0.70 ± 0.48 logMAR and 0.75 ± 0.32 logMAR before surgery to 0.21 ± 0.14 logMAR and 0.48 ± 0.19 logMAR 3 months after DMEK and DSAEK (P < .001), respectively, and to 0.17 ± 0.12 logMAR and 0.36 ± 0.15 logMAR 6 months after DMEK and DSAEK (P < .001), respectively. Endothelial cell density decreased from 2575 ± 260 cells/mm(2) and 2502 ± 220 cells/mm(2) before surgery to 1498 ± 244 cells/mm(2) and 1778 ± 420 cells/mm(2) 3 months after DMEK and DSAEK (P < .001), respectively, and to 1520 ± 299 cells/mm(2) and 1532 ± 495 cells/mm(2) 6 months after DMEK and DSAEK (P = .483), respectively. Central corneal thickness decreased from 652 ± 92 μm before surgery to 517 ± 45 μm 6 months after DMEK, and from 698 ± 137 μm before surgery to 618 ± 66 μm 6 months after DSAEK. DMEK provided faster and more complete visual rehabilitation when compared with DSAEK. However, there were no significant differences concerning endothelial cell survival within a 6-month follow-up.
    American Journal of Ophthalmology 03/2012; 153(6):1082-90.e2. · 4.02 Impact Factor
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    ABSTRACT: To describe the clinical results of Pentacam-based big bubble deep anterior lamellar keratoplasty (DALK) to achieve an intended 90% depth of initial lamellar trephination. Fifty consecutive eyes of 50 patients with keratoconus, keratoglobus, and anterior stromal scars were included. DALK was performed with the big bubble technique using a 90% intended depth for initial lamellar trephination based on preoperative pachymetry by Pentacam. Main outcome measures were success of surgery, best spectacle-corrected visual acuity, endothelial cell count, refractive astigmatism at 12-month follow-up, and rate of intra- and postoperative complications. In 84% of the patients (n = 42), Pentacam-based big bubble DALK could be performed successfully. Successful big bubble formation could be achieved in 80% of the patients (n = 34). In case of macroperforation (n = 8), surgery was converted to standard penetrating keratoplasty representing a conversion rate of 16%. Intraoperative microperforation (n = 5) could be handled by an intracameral air injection at the end of operation with successful completion of the lamellar procedure. No allograft rejection was observed. Best spectacle-corrected visual acuity improved from 20/125 ± 20/160 preoperatively to 20/40 ± 20/80 at 12-month follow-up. Endothelial cell count was 2102 ± 318 cells per square millimeter preoperatively and 1735 ± 420 cells per square millimeter at 12-month follow-up. Refractive astigmatism was 7.09 ± 3.13 diopters preoperatively and decreased to 4.13 ± 2.41 diopters. Pentacam-based big bubble DALK using a 90% intended depth of initial lamellar trephination seems to be a safe and effective procedure for anterior corneal stromal disorders such as keratoconus. We suggest that Pentacam-based depth assessment allows for reliably deep initial preparation and may allow more successful bubble formation in DALK surgery.
    Cornea 02/2012; 31(6):627-32. · 1.75 Impact Factor
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    ABSTRACT: We compared corneal higher-order aberrations (HOAs) in eyes after Descemet's membrane endothelial keratoplasty (DMEK), Descemet's stripping automated endothelial keratoplasty (DSAEK), and penetrating keratoplasty (PK), and in a control group that had not undergone surgery. Retrospective analysis of clinical data. Thirty eyes of 30 patients who had undergone standard DMEK, 20 eyes of 20 patients after DSAEK, 20 eyes of 20 patients after PK, and 20 eyes of 20 controls were analyzed. In addition to standard postoperative examinations, each participant was analyzed with the Pentacam high-resolution rotating Scheimpflug imaging system (Pentacam HR, Oculus, Wetzlar, Germany). Data were compared between groups. Visual acuity and HOAs. The mean follow-up was 6.5 ± 1.2 months after DMEK, 22.6 ± 11.8 months after DSAEK, and 103.1 ± 74.2 months after PK. There were no statistically significant differences for the anterior 4.0-mm zones between the DMEK group and the controls or between the DMEK and DSAEK groups. The DMEK procedure compared with PK showed statistically significant differences in all terms for the 4.0-mm zones. All combined Zernike terms for mean posterior aberrations of the central 4.0-mm zones showed statistically significant higher aberrations for DMEK compared with controls. The DMEK procedure compared with DSAEK showed statistically significant lower mean values for all combined Zernike terms, except for coma and coma-like terms in the central 4.0-mm zones of the posterior corneal surface. Compared with PK, DMEK showed statistically significant lower mean values for all combined Zernike terms for the central 4.0-mm zones of the posterior corneal surface, except for spherical aberration (SA) and SA-like terms. Best spectacle-corrected visual acuity (BSCVA) after DMEK was statistically significantly better than after DSAEK (P=0.001) and PK (P=0.005). There was no statistically significant difference when BSCVA was compared with controls (P=0.998). Both DSAEK and PK exhibit increased posterior corneal HOAs even years after surgery. Patients receiving DMEK display only slight changes in posterior corneal HOAs.
    Ophthalmology 12/2011; 119(3):528-35. · 5.56 Impact Factor
  • Bjoern Bachmann, Rod S Taylor, Claus Cursiefen
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    ABSTRACT: Purpose:  Corneal neovascularization (CNV) is thought to negatively influence visual acuity. New therapeutic options that offer a differentiated influence on the ingrowths or regression of either corneal blood or lymphatic vessels force us to re-evaluate the association between CNV and visual acuity. Methods:  A systematic review was conducted. Electronic databases were searched up to August 2009. Given the heterogeneity in study populations, interventions and measures of association, we were unable to undertake meta-analysis. The association between CNV and visual acuity was reported descriptively for each study. Results:  Eleven studies using either vascular endothelial growth factor inhibitor treatments (i.e. bevacizumab, Avastin(®) ; Hoffmann-La Roche AG, Basel, Switzerland) or an antiangiogenic treatment based on IRS-1 modulation [Gene-Signal (GS) 101, Aganirsen(®) ; GeneSignal, Evry (Paris), France] in a total of 131 patients (142 eyes) with corneal neovascularization were included. Ten of the eleven studies reported evidence of a statistically significant reduction in neovascularization following treatment. However, only four studies reported a statistically significant improvement in visual acuity following therapy. We found no studies that assessed the patient-level association between the change in neovascularization and visual acuity. Conclusion:  This systematic review found that there is currently weak evidence to support the hypothesis that in patients with pathological neovascularization, a treatment-related reduction in neovascularization is associated with an increase in visual acuity. There is a need for future appropriately designed studies.
    Acta ophthalmologica 11/2011; · 2.44 Impact Factor
  • B Bachmann, C Cursiefen
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    ABSTRACT: Severe chemical burns of the ocular surface frequently result in long-standing and ongoing disorders of the conjunctiva and the cornea including conjunctival scarring with shortening of the fornix, cicatricial entropion, complications caused by trichiasis and scarring or chronic ulceration of the cornea. Advanced destruction of limbal stem cells leads to limbal stem cell deficiency with conjunctivalization of the cornea. Surgical therapy aims at the correction of malpositioning of the lids, the reconstruction of the conjunctiva and the fornix utilizing applicable tissue grafts and the reestablishment of a stable, avascular and transparent corneal epithelium by e.g. transplantation of epithelial stem cells. Progressive corneal ulcerations unresponsive to medical therapy can be treated by amniotic membrane transplantation, corneal transplantation or by conjunctival covering depending on the extent of damaged tissue. The surgical therapy of patients after severe chemical burns of the ocular surface is generally performed in specialized centers and occasionally requires a multidisciplinary approach.
    Der Ophthalmologe 10/2011; 108(10):929-38. · 0.53 Impact Factor
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    ABSTRACT: To evaluate the feasibility of split cornea transplantation for 2 recipients by combining deep anterior lamellar keratoplasty (DALK) and Descemet membrane endothelial keratoplasty (DMEK). Interventional case series. Fifty consecutive eyes with anterior stromal disease suitable for DALK and 50 eyes with endothelial disease suitable for DMEK were scheduled for split cornea transplantation combining both procedures within 72 hours. Main outcome measures included success of using a single donor cornea for 2 recipients, best spectacle-corrected visual acuity (BSCVA), and complication rates within 6 months' follow-up. A single donor cornea could be used for 2 recipients in 47 cases (94%). In 3 eyes (6%), the DALK procedure had to be converted to penetrating keratoplasty (PK) requiring a full-thickness corneal graft. Thereby, 47 donor corneas (47%) could be saved. Six months after surgery, mean BSCVA was 20/36 in the 47 eyes that underwent successful DALK, 20/50 in the 3 eyes that underwent conversion from DALK to PK, and 20/29 in the 50 eyes that underwent DMEK. Postoperative complications after DALK included Descemet folds in 5 eyes (11%) and epitheliopathy in 3 eyes (6%). After DMEK, partial graft detachment occurred in 26 eyes (52%) and was managed successfully with intracameral air reinjection. All corneas remained clear up to 6 months after surgery. No intraocular infections occurred. Split use of donor corneal tissue for combined DALK and DMEK procedures in 2 recipients within 3 subsequent days is a feasible approach to reduce donor shortage in corneal transplantation in the future.
    American Journal of Ophthalmology 07/2011; 152(4):523-532.e2. · 4.02 Impact Factor

Publication Stats

695 Citations
128.52 Total Impact Points

Institutions

  • 2010–2014
    • Universitätsklinikum Erlangen
      • Department of Ophthalmology
      Erlangen, Bavaria, Germany
  • 2011–2013
    • University of Cologne
      • • Division of General Ophthalmology
      • • Department of Ophthalmology
      Köln, North Rhine-Westphalia, Germany
  • 2006–2013
    • Friedrich-Alexander Universität Erlangen-Nürnberg
      • • Department of Ophthalmology
      • • Department of Anatomy
      Erlangen, Bavaria, Germany
  • 2009
    • University of California, Berkeley
      Berkeley, California, United States