Objectives To investigate the correlation between postoperative endothelial cell loss (ECL) and donor, host, and surgical parameters, and to assess the clinical impact of maintaining a high endothelial cell density (ECD) of ≥ 1500 cells/mm2 5 years after penetrating keratoplasty (PKP). Methods This retrospective cohort study included 216 eyes with 5 years of follow-up, of which 94 had annual visits, and who underwent normal-risk elective PKP for noninfectious indications by one corneal microsurgeon (B. S.) between 2009 and 2016. Results Among the 216 eyes, ECL (39.1%) over 5 years postoperative exhibited weak positive correlations with storage solution time (p = 0.024) and postmortem time (p = 0.028), and moderately positively correlations with the preoperative ECD (p < 0.001). The 5-year postoperative ECL differed significantly between in domo-prepared (36.8%) and ex domo donor corneas (46.3%; p = 0.001). In the 94 eyes, no significant differences were found between the two groups for central pupil pachymetry (CCT) and BCVA (p > 0.074). However, CCT increased significantly between 1 and 4 years (p = 0.034) and 1 and 5 years postoperatively (p = 0.012), respectively. BCVA improved significantly at 1 year postoperatively and continued to improve until 2 years postoperatively (p < 0.001). Conclusion The Lions corneal bank Saar-Lor-Lux achieved a significantly reduced ECL (36.8%) over 5 years compared to ex domo donor corneas (46.3%). A weak positive correlation was found between ECL with the storage solution time and the postmortem time, as well as a moderate positive correlation with the preoperative ECD. Although CCT increased significantly over 5 years, BCVA improved significantly from the first to the second postoperative year and remained stable thereafter.

Zusammenfassung Hintergrund Ziel der vorliegenden Studie ist es, die Häufigkeit von Immunreaktionen und den Endothelzellverlust nach perforierender Keratoplastik (PKP) vs. Descemet Membrane Endothelial Keratoplasty (DMEK) bei Patienten mit Fuchs-Endotheldystrophie (FED) gegenüberzustellen. Patienten und Methoden In der vorliegenden retrospektiven Studie wurden insgesamt 962 Operationen (OPs; 225 Excimer-Laser-PKP und 727 DMEK) von 700 Patienten, die zwischen dem 28.06.2007 und dem 27.08.2020 in der Universitäts-Augenklinik des Saarlandes durchgeführt wurden, statistisch ausgewertet. Zum einen wurde die Prävalenz und der zeitliche Verlauf der aufgetretenen Immunreaktionen mittels Kaplan-Meier-Verfahren sowie die Auswirkungen der Immunreaktionen auf die Endothelzellen und die Hornhautdicke analysiert. Zum anderen wurden Endothelzelldichte, Pleomorphismus und Polymegalismus der Endothelzellen für die Zeitpunkte U1 = präoperativ, U2 = 6 Wochen postoperativ, U3 = 6 – 9 Monate postoperativ, U4 = 1 – 2 Jahre postoperativ und U5 = 5 Jahre postoperativ ausgewertet. Weiter erfolgte dazu jeweils eine statistische Testung auf Unterschiede zwischen den beiden OP-Arten sowie im longitudinalen Verlauf. Ergebnisse Insgesamt traten im beobachteten Zeitraum 54 Immunreaktionen auf, wobei die Wahrscheinlichkeit für eine solche bei der PKP mit 8,9% signifikant größer war als in der DMEK-Gruppe mit 4,5% (p = 0,011). Der Vergleich der beiden Kaplan-Meier-Kurven ergab im Log-Rank-Test ebenfalls einen signifikanten Unterschied zwischen den beiden OP-Techniken (p = 0,012). Der Endothelzellverlust durch die Immunreaktion war nur bei der PKP signifikant (p = 0,003). Auf alle OPs bezogen sank die Endothelzelldichte bei beiden OP-Techniken signifikant mit der Zeit (jeweils p < 0,0001), bei der DMEK stärker als bei der PKP (p < 0,0001). Außerdem war die Zelldichte bei der PKP insgesamt signifikant höher als bei der DMEK (p < 0,0001). Der Polymegalismus sank nur bei der DMEK-Gruppe signifikant (p < 0,0001). Der Pleomorphismus war im Durchschnitt bei der DMEK signifikant höher als bei der PKP (p < 0,0001). Schlussfolgerung Die Prognose der DMEK bei Patienten mit FED scheint nach Immunreaktionen günstiger zu sein als die der PKP, da nicht nur seltener Immunreaktionen auftraten, sondern diese auch milder verliefen. Die Endothelzelldichte war allerdings in der PKP-Gruppe während des gesamten Follow-ups signifikant höher.

Abstract Background and Purpose The etiology of keratoconus (KC) is probably multifactorial but remains essentially unknown. Previous scientific observations have suggested that hypothyroidism might play a role in the development and progression of KC. The purpose of this study was to analyze the tomographic and biomechanical parameters in KC patients with or without hypothyroidism. Methods Twenty-eight patients with KC and hypothyroidism (HT group) and fifty-six KC patients without thyroid dysfunction (WHT group) with matching gender and age were analyzed. Mean age was 40.3 years (range 14 – 57) in the HT group and 40.3 years (range 14 – 57) in the WHT group. Routine ophthalmic examinations consisted of corneal tomography and biomechanical parameters. We extracted the following KC parameters from the Pentacam (Pentacam HR, Oculus, Wetzlar, Germany): Keratoconus Index (KI), maximum keratometry (K max ), astigmatism, and thinnest pachymetry (TP). From the ocular response analyzer (ORA, Reichert Ophthalmic Instruments, Depew, NY, USA), we extracted corneal hysteresis (CH), corneal resistance factor (CRF), and KC match index (KMI). Results The comparison of the tomographic and biomechanical values from cross-sectional and longitudinal analyses showed no significant differences between the HT and WHT groups. Conclusion The severity of KC based on tomographical and biomechanical parameters does not seem to depend on the presence of hypothyroidism.

Purpose:Intraocular pressure (IOP) measurement may be difficult in keratoconus (KC) due to corneal protrusion and irregular astigmatism. This study aimed to assess which IOP measurement modality is least affected by KC severity.Methods:Data from 246 corneas of 246 patients with KC were retrospectively analyzed. KC stages were determined using the Topographic KC (TKC) and ABCD KC classifications derived from Pentacam (Oculus, Germany). IOP was measured using Goldmann applanation tonometry (GAT), Ocular Response Analyzer (ORA, Reichert Instruments, USA), and Corvis ST (CST, Oculus, Germany). Cronbach alpha (CA), analysis of variance with Bonferroni correction, Dunnett T3, and Pearson correlation were performed.Results:Using CA, the reliability of measurements using various modalities increased to 0.764 to 0.943 when excluding IOP Goldmann overall and in each KC stage (TKC and ABCD). Analysis of variance revealed significant differences between TKC and ABCD stages for almost all IOP modalities. The Bonferroni post hoc test showed significant differences between the measured IOP in earlier and advanced KC stages, except for the biomechanically CST-corrected IOP (bIOP). Pearson correlation analysis showed a significant correlation between IOP and thinnest corneal thickness (TCT) for all IOP modalities except bIOP.Conclusions:CST-based bIOP seems to be best suited for IOP measurement in KC because it did not correlate with TCT in contrast to IOP measurements by ORA or GAT. The measurement results from GAT in patients with KC should be interpreted with care and always in view of corneal thickness. As a thumb rule, we suggest to add at least 2 mm Hg to the measured GAT value.

Background The aim of this study was to compare the incidence of immune reactions and endothelial cell loss after penetrating keratoplasty (PKP) vs. Descemet membrane endothelial keratoplasty (DMEK) in patients with Fuchs endothelial dystrophy (FED).Patients and Methods In the present retrospective study, a total of 962 surgeries (225 excimer laser PKP and 727 DMEK) of 700 patients performed between 28.06.2007 and 27.08.2020 in the Department of Ophthalmology at Saarland University Medical Center UKS were statistically evaluated. On the one hand, the prevalence and the temporal course of the immune reactions that occurred were analysed using the Kaplan-Meier method, as well as the effect of the immune reactions on the endothelial cells and corneal thickness. Secondly, endothelial cell density, pleomorphism, and polymegethism of the endothelial cells were evaluated for the time points U1 = preoperative, U2 = 6 weeks postoperative, U3 = 6 to 9 months postoperative, U4 = 1 to 2 years postoperative, and U5 = 5 years postoperative. In addition, statistical tests were carried out for differences between the two types of surgery and in the longitudinal course.Results A total of 54 immune reactions occurred during the observed period, whereby the probability of such a reaction was significantly greater in the PKP group with 8.9% than in the DMEK group with 4.5% (p = 0.011). The comparison of the two Kaplan-Meier curves also showed a significant difference between the two surgical techniques in the log-rank test (p = 0.012). The endothelial cell loss due to the immune reaction was only significant in PKP (p = 0.003). For all surgical procedures, endothelial cell density decreased significantly with time in both surgical techniques (p < 0.0001 in each case), but more strongly with DMEK than with PKP (p < 0.0001). Furthermore, this cell density was significantly higher with PKP than with DMEK for the whole observation time (p < 0.0001). Polymegethism decreased significantly in the DMEK group (p < 0.0001). Pleomorphism was significantly higher, on average, in DMEK than in PKP (p < 0.0001).Conclusion The prognosis of DMEK in patients with FED seems to be more favourable after immune reactions than that of PKP, as not only were immune reactions less frequent, but they were also milder. However, endothelial cell density was significantly higher in the PKP group during the entire follow-up.

Abstract Purpose To report a case of simultaneous bilateral ophthalmic artery occlusion in diagnosed giant cell arteritis (GCA). Observations A 77-year-old male patient presented to the emergency department with simultaneous vision loss in both eyes for 3 hours. Headache at both temples and jaw claudication had been present for 3 weeks. Laboratory values demonstrated an initially increased C-reactive protein (CRP) of 202.0 mg/L and an erythrocyte sedimentation rate (ESR) of 100 mm within the first 20 minutes. Duplex sonography of the right and left temporal arteries revealed a “halo sign.” A case of GCA was suspected, and intravenous high-dose methylprednisolone therapy was immediately administered. The clinical examination revealed a bilateral central retinal artery occlusion and fluorescein angiography showed a hot optic disc in the right eye and patchy choroidal hypoperfusion in both eyes. Biopsy of the left temporal artery was performed, which confirmed a florid temporal arteritis with complete thrombotic occlusion of the vascular lumen. Despite a good response to the administered therapy (CRP 17.0 mg/L 1 week after initiation), the visual prognosis was significantly limited through retinal and optic nerve involvement. By the follow-up examination 8 weeks later, the near visual acuity was 20/400 in the right and left eye at a distance of 16 inches. Conclusion and Importance We hereby present a simultaneous bilateral ophthalmic artery occlusion as a rare complication of GCA. The combination of central retinal artery occlusion, arteritic anterior ischemic optic neuropathy, and choroidal hypoperfusion suggests an acute inflammatory involvement of the ophthalmic artery. In cases of the slightest suspicion of giant cell arteritis, an immediate high-dose steroid therapy initiation is of utmost importance.

Of the numerous biological activities attributed to nitric oxide (•NO), relatively little is known about its ability to intercept lipid-derived free radicals and thus protect cells against the damaging effects of lipid peroxidation, particularly in photodynamic settings. To address this, we asked how the •NO donor spermine-NONOate (SPER/NO) would affect porphyrin (PpIX)-photosensitized, iron/ascorbate-amplified chain peroxidation in cholesterol (Ch)/phospholipid (0.8:1.0, mol/mol) liposomes. Several Ch oxidation products (ChOX) were monitored by high performance chromatographic techniques. When added immediately before irradiation, SPER/NO (0.4 mM) had no effect on accumulation of 5α-hydroperoxide, a primary singlet oxygen-derived ChOX, but strongly suppressed the secondary species arising from postphotooxidation chain reactions, including 7α/7β-hydroperoxides, 7α/7β-hydroxides, and 5,6-epoxides. Metabolism of exogenous 5-aminolevulinate to PpIX in COH-BR1 tumor cells sensitized them to ChOX photogeneration and necrotic photokilling. When present during irradiation, active (but not decomposed) SPER/NO strongly inhibited both effects. These findings support the hypothesis that suitably presented NO, by intercepting lipid-derived radicals, can antagonize the antitumor effects of photodynamic therapy and other oxidative therapies.

PURPOSE:The aim of this study was to analyze the prevalence and severity of corneal guttata (CG) in grafts after penetrating keratoplasty (PKP) and to determine its clinical significance.METHODS:This retrospective study included 1758 PKP performed in 1522 patients. In total, 6662 postoperative endothelial images revealed the prevalence and severity of CG (divided into categories G0 without CG and G1-G3 with increasing severity). Origin of the graft, postoperative corneal thickness, visual acuity, pleomorphism, polymegethism, and endothelial cell density (ECD) were analyzed.RESULTS:CG was detected in 14.9% of the grafts within 9 months after PKP, most of them were low-grade G1 (13.6%). Grafts from Homburg/Saar showed significantly less CG cases compared with other eye banks ( P = 0.034). The mean corrected distance visual acuity (logMAR) did not differ between G1 (0.45 ± 0.31) and G0 (0.46 ± 0.31). The mean ECD was lower in G1 compared with G0 ( P < 0.001). The mean corneal thickness was higher in G3 (597 ± 101 μm) compared with G0 (541 ± 65 μm) ( P < 0.001). Pleomorphism and polymegethism were correlated with CG ( P < 0.001). A progression of CG severity was detected in 13.5% of the cases during a follow-up time of 25.0 ± 19.9 months.CONCLUSIONS:Our study suggested that CG are transplanted in 14.9% of PKP, most of which are low-grade CG not affecting the visual acuity but already leading to an increase in corneal thickness, loss of ECD, and alteration of endothelial cell morphology. In 13.5% of the cases, a progression was demonstrated in the postoperative course.

PURPOSE:To analyze endothelial cell density (ECD) and central corneal thickness (CCT) following penetrating keratoplasty (PKP) in Acanthamoeba keratitis (AK) patients. PATIENTS AND METHODS:In this retrospective, clinical, single-center, cross-sectional, observational study, patients were enrolled who underwent PKP at the Department of Ophthalmology of Saarland University Medical Center, Homburg/Saar, Germany between May 2008 and December 2016 with the diagnosis of AK. In all, 33 eyes of 33 patients (14 males, 42%) were enrolled; their mean age at the time of surgery was 39.5 ± 14.3 years. Postoperatively, AK patients received topical polyhexamethylene biguanide, propamidine isethionate, neomycin sulphate/gramicidin/polymixin B sulfate, and prednisolone acetate eye drops (5 ×/day each), and the topical treatment was tapered sequentially with 1 drop every 6 weeks over 6 months. CCT was recorded using Pentacam HR Scheimpflug tomography and ECD with the EM-3000 specular microscope before surgery and 3 and 6 months after surgery as well as after the first and second (complete) suture removal. RESULTS:ECD tended to decrease significantly from the time point before surgery (2232 ± 296 cells/mm2) to the time point 3 months after surgery (1914 ± 164 cells/mm2; p = 0.080) and to the time point after the first suture removal (1886 ± 557 cells/mm2; p = 0.066) and decrease significantly to the time point after the second suture removal (1650 ± 446 cells/mm2; p = 0.028). CCT did not change significantly over the analyzed time period (p ≥ 0.475). CONCLUSION:In AK, endothelial cell loss does not seem to be accelerated following PKP, despite the postoperative use of diamidine and biguanide. A subsequent prospective comparative study should confirm our retrospective longitudinal analysis.

Aim This retrospective investigated the impact of donor age, recipient age, donor endothelial cell density, vis-a-tergo, and additional intraoperative lens exchange (triple-procedure) on overall early and late phase postoperative endothelial cell density (ECD) following penetrating keratoplasty (PKP) in various diagnosis groups. Patients and Methods In 590 cases with diagnosed keratoconus (KC), Fuchs dystrophy (FD) and herpes simplex virus infection (HSV) who underwent PKP or triple surgery, the ECD in cells/mm (2) was analysed, both preoperatively, with all-sutures-in (early postoperative stage), and after last suture removal. The factors were tested by Mann-Whitney U-test, correlation analysis and linear regression analysis. Outcome Correlation analysis demonstrated a weak negative correlation between the patients ECD and donor age (early postoperative stage: r=-0.25, p<0.001; after last suture removal: r=-0.16; p=0.003). Regression analysis revealed that donor age did not impact postoperative patient ECD. There was a weak negative correlation between postoperative ECD and recipient age (early postoperative stage: r=-0.31, p<0.001; after last suture removal: r=-0.34, p<0.001). Regression analysis confirmed the negative impact of recipient age on patient ECD (early postoperative stage: beta=-13.2, p=0.001; after last suture removal: beta=-4.6, p<0.001). Correlation analysis determined a weak positive correlation between postoperative ECD and donor endothelial cell density (early postoperative stage: r=0.37, p<0.001; after last suture removal: r=0.32, p<0.001). Regression analysis also determined that donor endothelial cell density had a positive impact on postoperative ECD following last suture removal (beta=0.4, p<0.001). Vis-a-tergo and additional lens exchange (triple procedure) had no significant effect on postoperative ECD (p>0.05). This was also confirmed by the results of the regression analysis after last suture removal. Conclusion Recipient age and donor endothelial cell density have a significant impact on postoperative ECD following PKP. Not all of the statistical tests proved donor age to be a significant influencing factor. Vis-a-tergo and additional lens exchange (triple procedure) had no significant effect on postoperative ECD following PKP. Zusammenfassung Zielsetzung Ziel dieser retrospektiven Arbeit war es, den Einfluss des Spenderalters, des Empfangeralters, der Spenderendothelzelldichte, der Vis-a-tergo und des zusatzlichen Linsenaustausches (Triple Procedure) auf die postoperative Endothelzelldichte (EZD) insgesamt und im Zusammenhang mit zugrunde liegenden Erkrankungen in der Fruh- und Spatphase nach perforierender Keratoplastik (PKP) zu untersuchen. Patienten und Methoden Bei 590 Fallen mit den Diagnosen Keratokonus (KK), Fuchs-Dystrophie (FD) und Herpesvireninfektion (HSV), die eine PKP oder eine Triple-Operation erhalten haben, wurde praoperativ, mit liegenden Faden fruh postoperativ und nach Komplettfadenentfernung die EZD in Zellen/mm (2) untersucht. Die Einflussgro ss en wurden mittels Mann-Whitney-U-Test, Korrelations- und linearer Regressionsanalyse ausgewertet. Ergebnisse Zwischen der EZD des Patienten und dem Spenderalter zeigte sich in der Korrelationsanalyse ein schwach negativer Zusammenhang (fruh postoperativ: r=-0,25; p<0,001; nach Komplettfadenentfernung: r=-0,16; p=0,003). Die Regressionsanalyse ergab, dass das Alter des Spenders die postoperative EZD nicht beeinflusst. Die EZD des Patienten korrelierte schwach negativ mit dem Empfangeralter (fruh postoperativ: r=-0,31; p<0,001; nach Komplettfadenentfernung: r=-0,34; p<0,001). Die Regressionsanalyse bestatigte, dass die EZD des Patienten durch das Empfangeralter zu beiden postoperativen Zeitstadien negativ beeinflusst wird (fruh postoperativ: beta=-13,2; p=0,001; nach Komplettfadenentfernung: beta=-4,6; p<0,001). In der Korrelationsanalyse wurde ein schwach positiver Zusammenhang zwischen der postoperativen EZD und der Spenderendothelzelldichte festgestellt (fruh postoperativ: r=0,37; p<0,001; nach Komplettfadenentfernung: r=0,32; p<0,001). Auch die Regressionsanalyse ergab, dass die Spenderendothelzelldichte die postoperativen EZD nach Komplettfadenentfernung positiv beeinflusst (beta=0,4; p<0,001). Die Einflussfaktoren Vis-a-tergo und Triple-Operation zeigten keinen signifikanten Einfluss auf die postoperative EZD (p>0,05). Dies bestatigten auch die Ergebnisse der Regressionsanalyse nach der Komplettfadenentfernung. Schlussfolgerung Empfangeralter und Spenderendothelzelldichte haben signifikant Einfluss auf die postoperative EZD nach PKP. Das Spenderalter kann nicht in allen Tests als signifikante Einflussgro ss e nachgewiesen werden. Die Vis-a-tergo und die Triple-Operation haben keinen signifikanten Einfluss auf die postoperative EZD nach PKP.

Background This retrospective cross-sectional study aims to analyse the keratoconus (KC) stage distribution at different ages within the Homburg Keratoconus Center (HKC). Methods 1917 corneae (1000 patients) were allocated to decades of age, classified according to Belin’s ABCD KC grading system and the stage distribution was analysed. Results 73 per cent (n=728) of the patients were males, 27% (n=272) were females. The highest KC prevalence occurred between 21 and 30 years (n=585 corneae, 294 patients). Regarding anterior (A) and posterior (B) curvature, the frequency of A was significantly higher than B in all age groups for stage 0, 1 and 2 (A0>B0; A1>B1; A2>B2; p<0.03, Wilcoxon matched-pairs test). There was no significant difference between the number of A3 and B3, but significantly more corneae were classified as B4 than A4 in all age groups (p<0.02). The most frequent A|B combinations were A4|B4 (n=451), A0|B0 (n=311), A2|B4 (n=242), A2|B2 (n=189) and A1|B2 (n=154). Concerning thinnest pachymetry (C), most corneae in all age groups were classified as C0>C1>C2>C3>C4 (p<0.04, Wilcoxon matched-pairs test). For the best distance visual acuity (D), a significantly higher number of corneae were classified as D1 compared to D0 (p<0.008; D1>D0>D2>D3>D4). Conclusion The stage distributions in all age groups were similar. Early KC rather becomes manifest in the posterior than the anterior corneal curvature whereas advanced stages of posterior corneal curvature coincide with early and advanced stages of anterior corneal curvature. Thus, this study emphasises the necessity of posterior corneal surface assessment in KC as enabled by the ABCD grading system.

Purpose . To analyze the association between hypothyroidism and keratoconus, we examined blood thyroid hormone levels and corneal tomographic parameters in healthy subjects and patients with keratoconus. Methods . We included 626 subjects (304 left eyes, 49%; 431 males, 69%; age 38.4 ± 14.3 y). Patients with keratoconus were from our Homburg Keratoconus Center (HKC) ( n = 463); patients with hypothyroidism were from the Department of Internal Medicine of Saarland Medical University, Homburg/Saar, Germany ( n = 75); and healthy subjects were from the Department of Ophthalmology of Saarland University Medical Center ( n = 88). We included only one randomly selected eye of each subject and the first examination data. Exclusion criteria. Previous thyroid medication, previous ocular surgery, and patients with suspected keratoconus (topographic keratoconus classification, [TKC]: 0 < 1). Patient eyes were classified (TKC) with dedicated, instrument-based, keratoconus detection software provided with the Pentacam. TKC = 0 was considered “normal,” and TKCs ≥ 1 were considered keratoconus. Subjects were also classified as euthyroid or hypothyroid, based on blood thyroid hormone status (i.e., TSH, FT3, and FT4). A multiple logistic linear regression model was constructed to determine the effects of age (covariate), gender, and hypothyroidism (effect sizes) on “TKC-positive” disease. Results . The significance levels for a constant parameter, sex, thyroid condition, and age werep<0.0001,p<0.0001,p<0.0001, andp=0.003, respectively. The odds ratios for age, sex, and hypothyroidism were 0.98, 3.05, and 3.34, respectively. Male sex and a euthyroid condition had significantly positive, clinically relevant effects, and age had a significantly negative, but clinically irrelevant effect on the estimated TKC index. Conclusions . Keratoconus appeared to occur more often in patients classified as euthyroid than in patients with hypothyroidism. Thus, hypothyroidism alone could not support the development of keratoconus. Based on these results, it should not be mandatory to screen patients with hypothyroidism for keratoconus or patients with keratoconus for hypothyroidism.

We analysed histologically two Acanthamoeba keratitis (AK) eyes with anterior and posterior segment inflammation and blindness. Two enucleated eyes of 2 patients (age 45 and 51y) with AK (PCR of epithelial abrasion positive) were analysed. Histological analysis was performed using hematoxylin-eosin, periodic acid-Schiff and Gömöri-methenamine silver staining. We could not observe Acanthamoeba trophozoites or cysts neither in the cornea nor in other ocular tissues. Meanwhile, we found uveitis, retinal vasculitis and scleritis in these eyes, due to the long-standing, recalcitrant AK. So in this stage of AK, systemic immune suppression may be necessary for a longer time period.

Purpose: To analyze corneal surface temperature profile in a young and healthy study population and to determine the impact of corneal thickness (CT), anterior chamber depth (ACD), and endothelial cell density (ECD) on surface temperature.Methods: In this prospective, single-center study 61 healthy right eyes of 61 subjects without tear film pathologies (mean age 24.9 +/- 6.7 years) were recruited. Ocular surface temperature (OST) was measured with the Ocular Surface Thermographer TG-1000. From Pentacam HR CT and ACD, and from specular microscopy ECD and central corneal thickness (CCT) were acquired. From the raw measurement data (OST, CT and ACD) we extracted a) local OST the corneal center and 3 mm away from the center at the 3, 6, and 9 o'clock positions, and b) Zernike parameters Z1, Z2 and Z3 to evaluate the general temperature profile within a 6 mm circular area around the centerResults: Overall, there was no correlation between OST and CT, ACD or ECD. Local OST did not correlate with CT at any measurement position. On average local OST was highest at measurement positions where CT was lowest, but without reaching statistical significance. Baseline OST was highest at thin corneal regions and temperature decay over time was smallest in those regions. Z1, Z2 and Z3 correlated well with CTConclusions: In healthy subjects corneal thickness, endothelial cell density and anterior chamber depth have no effect on corneal surface temperature. The general temperature profile seems to be influenced by the corneal thickness profile effecting a higher temperature and lower decay at thinner corneal regions.

PURPOSE:To examine the microstructure of the cornea after excimer and femtosecond laser-assisted penetrating keratoplasty (ELAK and FLAK) in eyes with Fuchs' dystrophy and keratoconus.METHODS:Fifty-seven patients were divided into four groups according to corneal disease and surgical technique: Fuchs' dystrophy and ELAK (n = 9; mean age: 70.4 ± 10.6 years); Fuchs' dystrophy and FLAK (n = 13; mean age: 64.3 ± 11.2 years); keratoconus and ELAK (n = 9; mean age: 47.4 ± 13.9 years); and keratoconus and FLAK (n = 9; mean age: 43.5 ± 13.8 years). The control group comprised individuals without ocular disease (n = 17; mean age: 39.9 ± 17.3 years). In vivo investigation of the corneal graft and graft-host junction zone was performed with confocal corneal microscopy.RESULTS:All corneal grafts were transparent and no rejection reaction could be observed during the follow-up period. Confocal microscopy revealed no difference in basal epithelial cell density compared to controls. Anterior keratocyte density was lower than in the control group (818 ± 131 cells/mm(2)) in all four treatment groups (596 ± 174, 586 ± 113, 529 ± 75, 552 ± 91 cells/mm(2)). Langerhans cells could barely be seen; there was no difference in the cutting edge configuration and wound integrity.CONCLUSIONS:In vivo confocal microscopy provided evidence that good alignment of graft-host junction could be created with both techniques. The excimer laser was not inferior to the femtosecond laser in performing corneal cuts. The low density of Langerhans cells revealed well-controlled cellular immunological response and sustained corneal integrity in both laser groups.

Abstract Purpose: To determine the interaction between corneal topographic and tomographic parameters and dry eye syndrome (DES) in keratoconus (KC) patients. Methods: Seventy-seven eyes of 49 patients with KC (age 34.4 ± 11.6 years) were enrolled in this study. In these 77 eyes we recorded surface regularity index (SRI), surface asymmetry index (SAI) and Klyce/Maeda KC index (KCI) using the Topographic Modeling System (TMS-5, Tomey, Tennenlohe, Germany), Index of Surface Variance (ISV), Index of Vertical Asymmetry (IVA), KC Index (KI), Center KC Index (CKI), Index of Height Asymmetry (IHA) and Index of Height Decentration (IHD) using Pentacam (Pentacam HR, Oculus, Germany). Patients were subdivided into mild (grade 1–2) and severe stage (grade 3–4) KC groups according to Pentacam grading. To analyse tear film parameters we assessed in 77 KC eyes McMonnies questionnaire, Schirmer test and break-up time and in 26 eyes (10 eyes with mild KC, 16 eyes with severe KC) high-speed videokeratoscopy (during interblinking interval) using a novel commercially not available system (Tear Inspect). With Tear Inspect the analysed tear film parameters were (1) time of first irregularities of Placido rings and (2) time of eyelid closure. Patients were also subdivided into McMonnies questionnaire positive and negative groups. Results: We did not find significant difference between patients with mild and severe KC in any of the examined tear film parameters (p > 0.66). There was no significant difference in SRI, SAI, KCI, ISV, IVA, KI, CKI, IHA and IHD in McMonnies test positive and negative KC patients (p > 0.07). There was no correlation between SRI, SAI, KCI, ISV, IVA, KI, CKI, IHA and IHD and any of the examined tear film parameters (without high-speed videokeratoscopy) neither in 77 KC patients nor in mild or severe KC eyes (r < 0.3). Conclusions: There is no interaction between DES and topographic/tomographic changes in KC-patients.