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D Böhringer

Publications and source records attributed to D Böhringer.

At least 19 recordsLinked to original sources
PubMed2006

Clear graft survival and immune reactions following emergency keratoplasty.

BACKGROUND: Emergency penetrating keratoplasty is said to have a poorer outcome than conventional keratoplasty. We performed a retrospective analysis of 272 cases of emergency keratoplasty to evaluate this hypothesis. METHODS: We analysed 272 cases of emergency keratoplasty and compared the results with a control group of 1,257 scheduled normal-risk keratoplasties and 407 scheduled high-risk keratoplasties. Kaplan-Meier estimations were performed to estimate the percentage of clear graft survival and development of immune reactions. Indications for emergency keratoplasty were microbial diseases (n=109, acanthamoeba, bacteria, fungi), herpes simplex virus infections (n=83), ulcers due to immunological diseases (n=63), and 17 cases of ulcers of unknown origin. RESULTS: Within 1,500 postoperative days, grafts following emergency keratoplasty suffered statistically significantly more graft failures (clear graft survival, 67.9 vs. 86.9%, P<0.01) and immune reactions (grafts free from immune reactions, 62.8 vs. 78.6%, P<0.01) than grafts following scheduled, normal-risk keratoplasty. There was no statistically significant difference between emergency and scheduled high-risk keratoplasties (clear graft survival, 67.9 vs. 70.2%, and grafts free from immune reactions, 62.8 vs. 66.8%). For emergency keratoplasties, systemic immunosuppression (with cyclosporin A and/or mycophenolatmophetil) had a statistically significant positive effect on clear graft survival (77.4 vs. 63.5%, P=0.01), but not on the development of immune reactions (62.8 vs. 62.3%). A sub-group analysis showed that the effect on clear graft survival was mainly an effect on the underlying systemic immunological disease that had lead to emergency keratoplasty. CONCLUSION: This retrospective analysis revealed that clear graft survival is limited following emergency keratoplasty. As in high-risk situations, systemic immunosuppression may be the key to improving prognosis following emergency keratoplasty in the long run.

Adult↗
PubMed2006

Preserved vision despite distinct retinal edema in central retinal artery occlusion.

BACKGROUND: In subtotal central retinal artery occlusion (CRAO), distinct retinal edema with acute onset irreversible visual loss is common. - METHODS: Clinical observation, fluorescein angiogram. - PATIENT: A 69-year-old patient presented with acute visual loss of his right eye. Risk factors for CRAO were arterial hypertension and diabetes mellitus. A further factor was a 60% stenosis of the right and a 90% stenosis of the left internal carotid arteries. - RESULT: Visual acuity at initial examination was 20/32 despite pronounced central retinal edema with characteristic cherry red spot of the macula. Fluorescein angiography demonstrated early filling of retinal vessels, only perfusion of the inferior macular vessels was delayed. Two months later retinal edema resolved and central visual acuity was 20/25. - CONCLUSION: In this patient, retinal edema most likely resulted from a transient retinal ischemia. Spontaneous reperfusion occurred early enough to allow functional recovery in the ischemic retina.

Aged↗
PubMed2006

[Satisfaction with penetrating keratoplasty. Results of a questionnaire census].

BACKGROUND: Penetrating keratoplasty (PKP) is commonly referred to as the most successful transplantation procedure in medicine. This appraisal, however, is currently poorly supported by evidence. The aim of our study was to collect data on patient satisfaction with PKP as well as to analyze factors predisposing to dissatisfaction. PATIENTS AND METHODS: In the years 1988-2002 a total of 3,219 PKPs were performed on 2,981 patients. These patients were sent a questionnaire. The items pertained to subjective assessment of visual quality as compared to the situation before PKP and about regretting the PKP. RESULTS: The questionnaire was answered by 1,142 patients (59% of the traceable persons). The mean follow-up was 3.3+/-2.9 years. Indications for PKP were Fuchs' endothelial dystrophy (26%), keratoconus (23%), bullous keratopathy (15%), and further indications (36%). For these groups, best corrected visual acuity improved by more than two lines in 51, 80, 42, and 50%, respectively. The percentage of subjective improvement of vision was 73, 78, 47, and 63%. The percentage of regretting the PKP was 12, 4, 27, and 10%, respectively. All differences were highly statistically significant. Significant influencing factors on regretting the PKP were (inversely sorted for relevance): repeat graft failure, bullous keratopathy, contact lens wear, paresthesia, removal of running sutures, and patient age. CONCLUSIONS: General satisfaction with PKP is high. An important exception is bullous keratopathy, most likely due to accompanying morbidity (e.g., cystoid macular edema).

Attitude to Health↗
PubMed2004

[Posterior chamber lens implantation after penetrating keratoplasty. Is this partly responsible for late transplantation failure?].

BACKGROUND: Posterior chamber lens implantation (PCL) after penetrating keratoplasty (pKp) might contribute to late endothelial graft failure due to intraoperative damage of graft endothelium or due to PCL-associated facilitation of chronic endothelial cell loss. PATIENTS AND METHODS: A total of 55 eyes were retrospectively selected. By means of exponential regression analysis, individual annual relative endothelial cell loss was calculated. Six patients were pseudophakic prior to pKp (group A). Due to advanced cataracts in 18 patients (group B) a combined operation (triple-procedure) had been initially performed. Of the remaining 31 eyes. 17 underwent PCL implantation after a mean of 1.5+/-1.2 years post pKp during follow-up (group C). The remaining 14 eyes remained phakic during follow-up (group D). RESULTS: A statistically significant difference between the groups was not observed for the follow-up period or duration of culture ( p=0.14; Kruskal-Wallis-Test). Graft failures during follow-up were also not observed. CONCLUSION: From these preliminary results, cataract surgery does not seem to promote late endothelial failure after pKp.

Aged↗
PubMed2004

Improvement of graft prognosis in penetrating normal-risk keratoplasty by HLA class I and II matching.

BACKGROUND: Owing to contradictory results, HLA matching in penetrating keratoplasty still is equivocal. Different surgical techniques in multicentre studies, missing risk differentiation in high-risk situations, and faulty HLA typing can be identified as main reasons for these contradictory results. In this monocentre study, the value of HLA class I and II matching (A, B, DR loci) was examined in a homogeneous group of 418 normal-risk keratoplasty patients using serological typing techniques for HLA class I and immunogenetic typing techniques for class II. METHODS: Penetrating normal-risk keratoplasty was performed in two groups of patients (group I with 0-2, group II with 3-6 mismatches in the A/B/DR loci). All surgery was carried out by three experienced surgeons according to a standardized scheme. Furthermore, postoperative therapy and controls were standardized. There were no statistically significant differences between the two study groups with regard to the number of ABO or H-Y compatibilities, patient age, patient gender, ratio of previous intraocular surgery, ratio of triple procedures, indication for surgery, follow-up period, donor age, donor gender, post-mortem time of the graft, and endothelial cell density of the graft at the end of organ culture. All HLA typing was performed in a quality-controlled laboratory, serologically for HLA class I (A and B loci) and immunogenetically for HLA class II (DR locus). RESULTS: At 4 years postoperatively, the ratio of clear and rejection-free graft survival was 92% in group I and 66% in group II (Kaplan-Meier estimation, log rank test, P=0.03). Monovariate analysis in the Cox model gave no influence of solitary HLA class I or II matching, but only an influence of combined HLA class I and II matching (P=0.03). CONCLUSIONS: In this monocentre study with proper typing techniques, the beneficial effect of HLA class I plus II matching on clear and rejection-free graft survival could be demonstrated in a homogeneous group of normal-risk keratoplasty patients.

ABO Blood-Group System↗
PubMed2004

Endotoxin in storage medium of human corneal grafts and clinical course after penetrating normal-risk keratoplasty.

PURPOSE: It is well known that endotoxins in storage medium may stimulate cytokine production and expression of adhesion molecules as well as endothelial damage in human corneal grafts. It has been supposed that endotoxin exposure of corneal grafts may, therefore, cause immune reactions and lead to reduced endothelial cell count after penetrating keratoplasty. It was the purpose of this prospective study to evaluate if this hypothesis is true. METHODS: A consecutive series of 274 samples of sterile organ culture storage medium from 274 human corneal grafts was collected between August 1998 and February 1999 and tested for endotoxin using Limulus amebocyte-lysate assay (LAL) after 7 days of organ culture. Threshold endotoxin level was set at 1.0 U/ml. A total of 161 grafts were transplanted and 113 were discarded. Within the 161 corneas transplanted, 62 were grafted to normal-risk patients and 99 to high-risk patients. Only normal-risk keratoplasty patients were included in the study and followed for at least 10 months. Immune reactions, graft failures, and postoperative endothelial cell counts were recorded. RESULTS: The mean endotoxin level in organ culture medium of all transplanted grafts was 1.07+/-2.96. Mean endotoxin level in organ culture medium of discarded grafts was 1.68+/-5.76, with 71 samples being below and 42 above the threshold of 1.0 U/ml called endotoxin-negative and endotoxin-positive, respectively. In all 36 culture medium samples from the 62 grafts transplanted to the group of normal-risk keratoplasty patients were endotoxin-negative and 26 endotoxin-positive. An influence of endotoxin levels on incidence of immune reactions, graft failure, and postoperative endothelial cell counts could not be revealed in patients with normal-risk keratoplasty. CONCLUSION: Low endotoxin levels in storage medium neither seem to promote immune reactions nor to contribute to postoperative chronic endothelial cell loss in normal-risk keratoplasty patients.

Adolescent↗
PubMed2004

Investigation of cardiac and cardio-therapeutical phenomena using a pulsatile circulatory model.

For many years computer models of the cardiovascular system have existed with which the complex physiological interrelations of regulation processes may be studied. However, one major disadvantage of these models is the simplified modeling of the heart kinematics whereby the short term regulation effects of the heart itself on varying physical strains may only be simulated rudimentarily. The developed pulsatile model emphasizes the detailed description of the systolic wall tension progression subject to the Hill/Frank-Starling mechanisms and the simulation of the cardiac valves. Moreover, to be able to describe long term effects the pulsatile model was coupled to the established cardio vascular model of Guyton. Using the coupled system the influences of impaired valve function and ventricular relaxation disorders on the cardiac output as well as the need for an implementation of a physical strain dependent av-delay in existing pacemaker types were investigated. Both the dynamics and the steady-state values of a subset of variables (pressure, volume, flow) were successfully validated by comparing them to published experimental and clinical recordings.

Biomechanical Phenomena↗
PubMed2003

Individual analysis of expected time on the waiting list for HLA-matched corneal grafts.

OBJECTIVE: Recent studies report the beneficial effect of HLA matching for long-term prognosis of penetrating keratoplasty (kp). This improvement of prognosis, however, has to be weighed against the additional time on the waiting list due to the search for a HLA-compatible graft. Reliable estimation of this additional waiting period is a prerequisite for informed consent on the waiting policy. METHODS: A mathematical model based on survival analysis and HLA haplotype frequencies was used to estimate time on the waiting list for each of 1,400 HLA-typed patients registered at the Lions Cornea Bank NRW. Additionally, the waiting period of each patient was retrospectively determined. Both values were tested for correlation. This analysis was performed for acceptance of up to two mismatches on HLA-A, -B and -DR. RESULTS: When accepting two, one and zero mismatches, median predicted waiting period was 1 +/- 6, 7 +/- 49 and 17 +/- 159 months respectively. Median waiting period in retrospective simulation was 1 +/- 3, 5 +/- 9 and 15 +/- 14 months. Correlation of values from the predictive formula and simulation was statistically significant (p < 0.0001). CONCLUSION: Predicted time on the waiting list is a valuable tool for management of HLA matching in kp.

Cornea↗
PubMed2002

[Perforating keratoplasty with transplants from pseudophakic donors].

PURPOSE: Pseudophacia is considered to be a relative exclusion criterion for cornea donation. The aim of this retrospective study was to investigate the clinical outcome and prognosis of penetrating keratoplasty with grafts from pseudophacic donors. PATIENTS AND METHODS: From April 1996 to July 2000 16 patients received grafts from pseudophacic donors (group I). The control group (group II) comprised 26 patients with grafts from donors without a history of intraocular surgery. Graft survival, ratio of grafts without immune reactions and chronic endothelial cell loss were compared between both groups. RESULTS: During a follow-up of almost 1 year, no graft failures and no graft rejections were observed in group I. In group II 90% of the grafts remained clear and 91% of the grafts remained free of immune reactions in the same follow-up period (Kaplan-Meier estimation). The differences between the study groups were not statistically significant. Chronic endothelial cell loss was 0.86 +/- 0.82 cells per mm2 and day in group I and 1.4 +/- 1.8 cells per mm2 and day in group II. This difference was not statistically significant. CONCLUSION: Our clinical results reveal no reason to regard pseudophacia as a principal contraindication for cornea donation, provided a critical endothelial evaluation is carried out.

Aged↗
PubMed2002

Predicting time on the waiting list for HLA matched corneal grafts.

Recent studies report the beneficial effect of HLA matching for the long-term prognosis of penetrating keratoplasty (KP). This improvement in prognosis, however, has to be weighed against the additional waiting time while a HLA compatible graft is found. Precise estimation of this additional waiting period is a prerequisite for informed consent on the waiting policy. A mathematical model based on survival analysis and HLA haplotype frequencies was used to estimate time on the waiting list for each of 1400 HLA typed patients registered at the Lions Cornea Bank North Rhine Westfalia (NRW). Additionally, the waiting period for each patient was retrospectively determined. Both values were tested for correlation. This analysis was performed for acceptance of up to two mismatches on HLA-A, -B and -DR. The median predicted waiting period was compatible with the median waiting period in retrospective simulation. Correlation of both entities was statistically significant also. Predicted time on the waiting list as derived from the patient's HLA genotype and a comprehensive database of HLA haplotype frequencies is thus a valuable tool for management of HLA-matching in KP.

Corneal Transplantation↗
PubMed2001

Topical treatment of acute adenoviral keratoconjunctivitis with 0.2% cidofovir and 1% cyclosporine: a controlled clinical pilot study.

OBJECTIVE: To evaluate the efficacy of 0.2% cidofovir eyedrops and 1% cyclosporine eyedrops administered 4 times daily (qid) to treat acute adenoviral keratoconjunctivitis. METHODS: A randomized, controlled, double-masked study was conducted on 39 patients with acute adenoviral keratoconjunctivitis of recent onset. Patients were divided into 4 treatment groups: (1) cidofovir qid, (2) cyclosporine qid, (3) cidofovir + cyclosporine qid, and (4) sodium chloride qid (control). The diagnosis was confirmed using adenoviral polymerase chain reaction from conjunctival swabs. Duration of treatment was 21 days. MAIN OUTCOME MEASURES: Severity of conjunctival hyperemia, conjunctival chemosis, superficial punctate keratitis during treatment, and presence and severity of corneal subepithelial infiltrates were evaluated using a clinical score. Duration until subjective improvement of symptoms was recorded. RESULTS: Subjective improvement of local symptoms was accelerated in the cyclosporine group. All other clinically relevant variables showed no statistically significant difference among the 4 treatment groups. Particularly, we did not find a difference in the frequency of corneal subepithelial infiltrates at the end of treatment. CONCLUSIONS: Use of cidofovir, cyclosporine, or both did not accelerate the improvement of clinical symptoms of acute adenoviral keratoconjunctivitis compared with the natural course of the infection as demonstrated by this pilot study. This might be because of the wide spectrum of the clinical course of the infection, low sensitivity to cidofovir, too low of a concentration of cidofovir, or early cessation of viral replication in the course of the infection. The effect of a higher concentration of topical cidofovir with and without cyclosporine requires investigation in a larger group of patients.

Acute Disease↗
PubMed2001

Systemic mycophenolate mofetil in comparison with systemic cyclosporin A in high-risk keratoplasty patients: 3 years' results of a randomized prospective clinical trial.

BACKGROUND: With the use of systemic cyclosporin A (CsA), graft prognosis after high-risk penetrating keratoplasty has improved considerably. However, the application of CsA is limited owing to a variety of severe side effects. In this prospectively randomized study mycophenolate mofetil (MMF), a safe and efficient immunosuppressive medication after renal transplantation, was compared with CsA after high-risk penetrating keratoplasty. METHODS: Twenty-nine high-risk keratoplasty patients were treated with MMF 2x 1 g daily; another 27 patients received CsA, aiming at blood trough levels of 120-150 ng/ml. Systemic immunosuppression was scheduled for 6 months. In both groups oral corticosteroids (fluocortolone 1 mg/kg) were administered for 3 weeks postoperatively. RESULTS: During the first year after operation, no graft failure was recorded. Two years postoperatively 92%/82% and 3 years postoperatively 74%/69% of grafts were clear in the MMF and CsA group, respectively (Kaplan Meier P=0.33, logrank test). In total, two graft failures were recorded in the MMF group and four in the CsA group. Three years postoperatively 53% of the grafts were rejection-free in the MMF group and 73% in the CsA group (Kaplan Meier P=0.46, log-rank test). Eight endothelial immune reactions were observed in the MMF group (three under systemic immunosuppression/five thereafter; six mild/two severe) and five in the CsA group (three under systemic immunosuppression/two thereafter; three mild/two severe). Side effects occurred in six patients under MMF and 11 under CsA. CONCLUSIONS: Concerning efficacy, no statistically significant difference between systemic MMF and systemic CsA administered for 6 months after high-risk penetrating keratoplasty could be shown. Systemic MMF was proven to be at least as safe as CsA. The main mechanism in improving graft survival is a shift from severe to milder endothelial immune reactions, as already demonstrated for CsA. Thus, MMF may become an alternative to CsA for immunosuppression after penetrating high-risk keratoplasty. About 2 years postoperatively, pharmacologically induced relative immunological tolerance slowly decreases. Therefore, long-term administration of systemic MMF should be evaluated in further studies.

Adolescent↗
PubMed2001

[Regression analysis of idiopathic endothelial cell loss after perforating normal risk keratoplasty: basic principles for long-term analysis of endothelial risk factors in a retrospective clinical study].

BACKGROUND: For the characterisation of influencing factors on chronic endothelial cell loss after penetrating keratoplasty by means of multivariate statistics, a mathematical description of the course of the individual postoperative endothelial cell density is a prerequisite. This mathematical description should result in a standardized index value describing course and amount of the postoperative endothelial cell loss over time in a canonical way. The slopes of the linear regression lines for each individual scatter plot of a) the endothelial cell density values plotted against the respective postoperative time directly (linear regression), and b) after logarithmic transformation (exponential regression) are evaluated, respectively. PATIENTS AND METHODS: 58 patients after normal-risk keratoplasty (26x keratokonus, 22x Fuchs-dystrophy and 10 cases of corneal decompensation after cataract surgery) with 5 or more postoperatively acquired endothelial density values and without any episodes of graft rejection were included in this study. Mean follow up was 2.9 +/- 1.1 years. The postoperative endothelial cell density values were plotted against the respective time for each patient individually. The coefficients of variation (R2) derived from the linear and the exponential regression models were calculated for each of these scatter plots. The pairs of R2 values (linear vs. exponential) were compared statistically. A dependence of the difference of linear and exponential R2-values on the ophthalmologic diagnosis was tested as well. RESULTS: The linear model is able to declare 83% the total variance of the course of the endothelial cell density. The exponential model even declares 86%. This small difference was statistically significant. Since both methods of regression describe the course of the cell density well, intra/and extrapolation of missing endothelial values is possible with both models. No dependence of the difference of linear and exponential R2-values on the ophthalmologic diagnosis could be demonstrated. CONCLUSIONS: Both, the intuitively understandable slope of the linear regression line and the constant of decay of the exponential regression curve, are suitable for describing the amount of the postoperative loss of endothelial cells after normal-risk keratoplasty independent of the ophthalmologic diagnosis. Both can thus be used as target variable in forthcoming statistical analyses for chronic endothelial cell loss.

Adult↗
PubMed2001

[FK 506 ointment 0.1 % - A new therapeutic option for atopic blepharitis. Clinical trial with 14 patients].

BACKGROUND: Severe atopic blepharitis is difficult to treat, as topical steroids offer only a limited therapeutic benefit with increasing side effects by time. Topical FK 506 was found to be efficient and safe for treatment of atopic dermatitis in dermatologic studies. The use of topical FK 506 in atopic blepharitis has not been reported so far. PATIENTS AND METHODS: Fourteen patients with severe atopic blepharitis were treated with topical FK 506 0.1 %. The ointment was applied twice daily on the eye lids. Ophthalmologic examinations were scheduled at two weeks, two months and five months after onset of treatment. A score was defined for the skin of the lid (edema, erythema, lichenification, oozing, excoriation and crusting) and for the eye lid margin (erythema, thickening, crusting) respectively. Every patient graded pruritus on a visual analogue scale. RESULTS: The mean skin score prior to treatment was 25.6 +/- 5.8, after two weeks 7.9 +/- 4.8 (p < 0.001), after two months 5.8 +/- 5.0 (p < 0.001) and after five months 5.3 +/- 5.3 (p < 0.001). The mean score for the eye lid margin prior to treatment was 12.3 +/- 4.0, after two weeks 4.6 +/- 2.7 (p < 0.001), after two months 3.8 +/- 2.4 (p < 0.001) and after five months 4.3 +/- 2.6 (p < 0.001). The mean score for pruritus prior to treatment was 8.1 +/- 1.3, after two weeks 2.0 +/- 1.4 (p < 0.001), after two months 1.3 +/- 0.8 (p < 0.001) and after five months 0.8 +/- 0.7 (p < 0.001). All patients assessed the overall situation under therapy as markedly improved. CONCLUSIONS: Topical FK 506 0.1 % ointment turns out to be an excellent therapeutic option for treatment of severe atopic blepharitis. Long-term efficacy and safety have to be evaluated in long-term follow-up studies.

Administration, Topical↗
PubMed2001

Accelerated chronic endothelial cell loss after penetrating keratoplasty in glaucoma eyes.

PURPOSE: Accelerated chronic endothelial cell loss may be the main reason for limited prognosis of penetrating corneal grafts in glaucoma eyes. This hypothesis, however, has not yet been proven and is examined in this article. METHODS: Three groups of normal-risk keratoplasty patients were followed up prospectively. Group I consisted of 172 patients (without glaucoma history and without postoperative increase in intraocular pressure), group II comprised 15 patients (with glaucoma history, but without postoperative increase in intraocular pressure), and group III consisted of seven patients (with glaucoma history and with postoperative increase in intraocular pressure). Immune reactions in the postoperative course were an exclusion criterion. Follow-up periods averaged 2.7 +/- 1.7 years (group I), 2.8 +/- 1.7 years (group II), and 2.6 +/- 2.0 years (group III). Only patients with at least three postoperative endothelial cell density values were included in the study. Loss of endothelial cells. mm-2. d-1 was derived from the postoperative endothelial values of each patient by calculating the slope of the regression line for each scatterplot of endothelial cell density values plotted against time. RESULTS: During the follow-up period 0.82 +/- 0.97 cells. mm-2. d-1 were lost in group I, 1.01 +/- 1.04 cells. mm-2. d-1 were lost in group II, 2.67 +/- 2.16 cells. mm-2. d-1 were lost in group III (ANOVA and Gabriel post-hoc test: I/II P = 0.82, I/III P < 0.001, II/III P = 0.004). CONCLUSIONS: Postoperative increase in intraocular pressure may be a possible cause for accelerated endothelial cell loss in glaucoma eyes, but this result is tentative because of the small number of patients included in the two glaucoma groups. Confirmation by long-term observation of larger patients groups is desirable. The result implies good control of intraocular pressure after penetrating keratoplasty. Whether this method is the correct means by which to prevent accelerated endothelial cell loss in such eyes must be shown in future studies.

Aged↗