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1.
BMC Ophthalmol ; 23(1): 324, 2023 Jul 17.
Article En | MEDLINE | ID: mdl-37460946

BACKGROUND: Retinal breaks (RB) are emergencies that require treatment to prevent progression of rhegmatogenous retinal detachment. Vitreal hyperreflective foci (VHF) representing migration of RPE cell clusters or interphotoreceptor matrix from the RB are potential biomarkers. The aim of this study is to investigate VHF in RB-patients using SD-OCT. METHODS: The retrospective cross-sectional study included RB patients from our Department of Ophthalmology, HSK Wiesbaden who underwent macular SD-OCT (SPECTRALIS®, Heidelberg Engineering, Germany) on both eyes. VHF, defined and quantified as foci that differ markedly in size and reflectivity from the background speckle pattern, were assessed for presence and frequency. The RB-affected eyes were the study group (G1), the partner eyes the control group (G2). RESULTS: 160 consecutive patients with RB were included. Age was 60 ± 10.2 years (52% female). 89.4% of G1 and 87.5% of G2 were phakic (p = 0.73). 94.4% (n = 151) were symptomatic. Symptom duration was 8.0 ± 10.1 days in G1, 94.4% (n = 151) showed VHF versus 5.6% (p < 0.0001) in G2, of which 75% (n = 6) showed asymptomatic lattice degenerations. Detectable VHF showed a strong association of OR = 320 (95% CI, 110-788, p < 0.0001)) with respect to symptomatic RB. Sensitivity and specificity were 94.7% and 94.7%, respectively. CONCLUSIONS: Most eyes with symptomatic RB show vitreal VHF in SD-OCT. Detected VHF are strongly associated with RB, and our semi-automated greyscale reflectivity analysis indicates that VHF likely originate from photoreceptor complexes torn out of the RB area that migrate into the vitreous cavity. The presence of VHF may indicate RB and should lead to a thorough fundus examination in both symptomatic and asymptomatic cases.


Retinal Detachment , Retinal Perforations , Humans , Female , Middle Aged , Aged , Male , Retinal Perforations/diagnosis , Retrospective Studies , Tomography, Optical Coherence/methods , Cross-Sectional Studies , Retinal Detachment/diagnosis
2.
Ophthalmologie ; 120(7): 726-733, 2023 Jul.
Article De | MEDLINE | ID: mdl-36729123

OBJECTIVE: The need for care in ophthalmology is constantly increasing due to demographic changes. The study analyzed the current professional situation and future prospects of ophthalmologists under 49 years old. METHODS: The survey of members of the German Association of Ophthalmologists (Berufsverband der Augenärzte Deutschlands) and the German Ophthalmologic Society (Deutsche Ophthalmologische Gesellschaft) was conducted in 2022. All members under the age of 49 years received an online questionnaire on the current professional situation as well as future perspectives (desired working hours, form of organization). The results of the survey were additionally compared with the 2016 survey of the German Association of Ophthalmologists. A similar questionnaire was used at that time. RESULTS: A total of 1014 people participated in the survey (62.7% women, mean age 39.3 ± 8 years, 75.6% specialists). The response rate to the survey was 25%. Specialist practice from 0 to 5 years showed a higher number of employed ophthalmologists (21% self-employed vs. 32% employed); over time the number of self-employed ophthalmologists increased (6-10 years: 40%, > 10 years: 59.3%). Overall, 46% of women were employed in a practice compared with 33% of men. Of the self-employed specialists, 95.9% said they planned to work in the same type of employment in 10 years as currently. Regarding ophthalmologists' career future, the other employment types showed a desire to move to independent practice. Compared to the 2016 survey, gender differences related to the current type of employment were evident. The number of self-employed women decreased from 43% to 26% and self-employed men decreased from 63% to 39%. The number of ophthalmologists in ambulatory healthcare centers was doubled compared to 2016. Ophthalmologists reported similar future perspectives at both survey times. CONCLUSION: The results of the survey of ophthalmologists under 49 years in Germany showed similar perceptions as in 2016. It became clear that the desire to be self-employed in 10 years is very high; however, ophthalmologists expected large practices or medical care centers to prevail in the market. The number of self-employed doctors is decreasing and the desire for self-employment is difficult to realize.


Ophthalmologists , Ophthalmology , Physicians , Male , Humans , Female , Adult , Middle Aged , Surveys and Questionnaires , Employment
4.
BMC Ophthalmol ; 22(1): 56, 2022 Feb 05.
Article En | MEDLINE | ID: mdl-35123423

BACKGROUND: Spectral domain optical coherence tomography (SD-OCT) is a widely applied non-invasive technique for evaluating optic nerve head parameters. The aim of this study was to evaluate the impact of biometric parameters such as the spherical equivalent (SE) and the anterior corneal curvature (ACC) on the peripapillary retinal nerve fiber layer (pRNFL), Bruch's membrane opening (BMO), and the minimum rim width (MRW) measurements performed by spectral domain optical coherence tomography (SD-OCT) in glaucomatous and healthy eyes. METHODS: In this cross-sectional, case-control prospective pilot study, the glaucoma group consisted of 50 patients with previously diagnosed and treated glaucoma and one healthy group of 50 subjects. Two consecutive examinations of pRNFL, BMO, and MRW with SD-OCT for every patient were performed without ACC and objective refraction (imaging 1) and with them (imaging 2). RESULTS: The interclass correlation coefficient (ICC) reflected high agreement between imaging 1 and imaging 2 in both groups. The ICC in the glaucoma and healthy groups for pRNFL (0.99 vs. 0.98), BMO (0.95 vs. 0.97), and MRW (1.0 vs. 1.0) was comparable. CONCLUSIONS: Our preliminary data from a small number of eyes showed that the measurements of pRNFL, MRW, and BMO reflected high agreement between both imaging techniques with ACC and objective refraction and without these parameters in subjects with a refractive error up to ± 6.0 diopters. Further studies with participants with higher refractive error are necessary to evaluate the impact of biometric parameters such as SE and ACC on measurements with SD-OCT.


Optic Disk , Biometry , Bruch Membrane , Cross-Sectional Studies , Humans , Intraocular Pressure , Nerve Fibers , Pilot Projects , Prospective Studies , Retinal Ganglion Cells , Tomography, Optical Coherence
5.
Sci Rep ; 11(1): 12883, 2021 Jun 18.
Article En | MEDLINE | ID: mdl-34145307

We present structure and equation of state (EOS) measurements of biaxially orientated polyethylene terephthalate (PET, [Formula: see text], also called mylar) shock-compressed to ([Formula: see text]) GPa and ([Formula: see text]) K using in situ X-ray diffraction, Doppler velocimetry, and optical pyrometry. Comparing to density functional theory molecular dynamics (DFT-MD) simulations, we find a highly correlated liquid at conditions differing from predictions by some equations of state tables, which underlines the influence of complex chemical interactions in this regime. EOS calculations from ab initio DFT-MD simulations and shock Hugoniot measurements of density, pressure and temperature confirm the discrepancy to these tables and present an experimentally benchmarked correction to the description of PET as an exemplary material to represent the mixture of light elements at planetary interior conditions.

6.
Phys Rev Lett ; 126(1): 015703, 2021 Jan 08.
Article En | MEDLINE | ID: mdl-33480771

We present results from the SPring-8 Angstrom Compact free electron LAser facility, where we used a high intensity (∼10^{20} W/cm^{2}) x-ray pump x-ray probe scheme to observe changes in the ionic structure of silicon induced by x-ray heating of the electrons. By avoiding Laue spots in the scattering signal from a single crystalline sample, we observe a rapid rise in diffuse scattering and a transition to a disordered, liquidlike state with a structure significantly different from liquid silicon. The disordering occurs within 100 fs of irradiation, a timescale that agrees well with first principles simulations, and is faster than that predicted by purely inertial behavior, suggesting that both the phase change and disordered state reached are dominated by Coulomb forces. This method is capable of observing liquid scattering without masking signal from the ambient solid, allowing the liquid structure to be measured throughout and beyond the phase change.

7.
Nat Commun ; 11(1): 2620, 2020 May 26.
Article En | MEDLINE | ID: mdl-32457297

The gas and ice giants in our solar system can be seen as a natural laboratory for the physics of highly compressed matter at temperatures up to thousands of kelvins. In turn, our understanding of their structure and evolution depends critically on our ability to model such matter. One key aspect is the miscibility of the elements in their interiors. Here, we demonstrate the feasibility of X-ray Thomson scattering to quantify the degree of species separation in a 1:1 carbon-hydrogen mixture at a pressure of ~150 GPa and a temperature of ~5000 K. Our measurements provide absolute values of the structure factor that encodes the microscopic arrangement of the particles. From these data, we find a lower limit of [Formula: see text]% of the carbon atoms forming isolated carbon clusters. In principle, this procedure can be employed for investigating the miscibility behaviour of any binary mixture at the high-pressure environment of planetary interiors, in particular, for non-crystalline samples where it is difficult to obtain conclusive results from X-ray diffraction. Moreover, this method will enable unprecedented measurements of mixing/demixing kinetics in dense plasma environments, e.g., induced by chemistry or hydrodynamic instabilities.

8.
Sci Rep ; 9(1): 4196, 2019 Mar 12.
Article En | MEDLINE | ID: mdl-30862904

We investigated the high-pressure behavior of polyethylene (CH2) by probing dynamically-compressed samples with X-ray diffraction. At pressures up to 200 GPa, comparable to those present inside icy giant planets (Uranus, Neptune), shock-compressed polyethylene retains a polymer crystal structure, from which we infer the presence of significant covalent bonding. The A2/m structure which we observe has previously been seen at significantly lower pressures, and the equation of state measured agrees with our findings. This result appears to contrast with recent data from shock-compressed polystyrene (CH) at higher temperatures, which demonstrated demixing and recrystallization into a diamond lattice, implying the breaking of the original chemical bonds. As such chemical processes have significant implications for the structure and energy transfer within ice giants, our results highlight the need for a deeper understanding of the chemistry of high pressure hydrocarbons, and the importance of better constraining planetary temperature profiles.

9.
BMC Ophthalmol ; 18(1): 157, 2018 Jun 28.
Article En | MEDLINE | ID: mdl-29954361

BACKGROUND: To investigate the prevalence of depression and anxiety among subjects with self-reported glaucoma and the association between self-reported glaucoma and depression respectively anxiety in a European cohort. METHODS: A study sample of 14,657 participants aged 35 to 74 years was investigated in a population-based cohort study. All participants reported presence or absence of glaucoma. Ophthalmological examinations were carried out in all participants and demographic and disease related information were obtained by interview. Depression was assessed with the Patient Health Questionnaire (PHQ-9), and generalized anxiety with the two screening items (GAD-2) of the short form of the GAD-7 (Generalized Anxiety Disorder-7 Scale). Prevalence of depression and generalized anxiety were investigated for subjects with and without self-reported glaucoma. Logistic regression analyses with depression, respectively anxiety as dependent variable and self-reported glaucoma as independent variable were conducted and adjusted for socio-demographic factors, systemic comorbidities (arterial hypertension, myocardial infarction, stroke, diabetes mellitus, chronic obstructive pulmonary disease, cancer), ocular diseases (cataract, macular degeneration, corneal diseases, diabetic retinopathy), visual acuity, intraocular pressure, antiglaucoma eye drops (sympathomimetics, parasympathomimetics, carbonic anhydrase inhibitors, beta-blockers, prostaglandins) and general health status. RESULTS: 293 participants (49.5% female) reported having glaucoma. Prevalence of depression among participants with and without self-reported glaucoma was 6.6% (95%-CI 4.1-10.3) respectively 7.7% (95%-CI 7.3-8.2), and for anxiety 5.3% (95%-CI 3.1-8.7) respectively 6.6% (95%-CI 6.2-7.1). Glaucoma was not associated with depression (Odds ratio 1.10, 95%-CI 0.50-2.38, p = 0.80) or anxiety (1.48, 95%-CI 0.63-3.30, p = 0.35) after adjustment for socio-demographic factors, ocular/systemic diseases, ocular parameters, antiglaucoma drugs and general health status. A restriction to self-reported glaucoma cases either taking topical antiglaucoma medications or having a history of glaucoma surgery did not alter the result. CONCLUSIONS: This is the first study analyzing both depression and anxiety among glaucoma patients in a European cohort. Subjects with and without self-reported glaucoma had a similar prevalence of depression and anxiety in our population-based sample. Self-reported glaucoma was not associated with depression or anxiety. A lack of a burden of depressive symptoms may result from recruitment from a population-based sample as compared to previous study groups predominantly recruited from tertiary care hospitals.


Anxiety Disorders/epidemiology , Depressive Disorder/epidemiology , Glaucoma/psychology , Adult , Aged , Cohort Studies , Cross-Sectional Studies , Female , Germany/epidemiology , Humans , Logistic Models , Male , Middle Aged , Prevalence
11.
Phys Rev Lett ; 121(24): 245501, 2018 Dec 14.
Article En | MEDLINE | ID: mdl-30608736

We present results for the ionic structure in hydrocarbons (polystyrene, polyethylene) that were shock compressed to pressures of up to 190 GPa, inducing rapid melting of the samples. The structure of the resulting liquid is then probed using in situ diffraction by an x-ray free electron laser beam, demonstrating the capability to obtain reliable diffraction data in a single shot, even for low-Z samples without long range order. The data agree well with ab initio simulations, validating the ability of such approaches to model mixed samples in states where complex interparticle bonds remain, and showing that simpler models are not necessarily valid. While the results clearly exclude the possibility of complete carbon-hydrogen demixing at the conditions probed, they also, in contrast to previous predictions, indicate that diffraction is not always a sufficient diagnostic for this phenomenon.

12.
Ophthalmologe ; 115(12): 1042-1049, 2018 Dec.
Article De | MEDLINE | ID: mdl-29110124

BACKGROUND: The prevalence of eye diseases increases in the second half of life, especially cataract, glaucoma and age-related macular degeneration. In this study we examined the influencing factors for visiting an ophthalmologist in the last 12 months. METHODS: Visits to an ophthalmologist's practice in the last 12 months and the frequency were surveyed in the German nationwide adult health survey wave 1 (DEGS1) study (baseline examination from 2008 to 2011, N = 7987, 52.6% women, age 18-79 years). Data on utilization were processed by taking the complex study design into consideration. Multivariable logistic regression analysis was used to determine associated factors including age, sex, socioeconomic status, place of residence, type of health insurance (e.g. statutory or private) and diabetes. RESULTS: Between the ages of 18 and 79 years, 29.3% of survey participants in Germany visited an ophthalmologist in the last year, while after the age of 60 years this was only 50.4%. Multivariable logistic regression analysis showed an association with female sex (odds ratio OR = 1.51, p < 0.001), older age, type of health insurance (private vs. statutory: OR = 0.77, p = 0.006) and diabetes (OR = 3.84, p < 0.001), but no association with socioeconomic status (p = 0.29) or place of residence (p = 0.06). CONCLUSION: Approximately one third of the German population visit an ophthalmologist at least once a year. Especially diabetics showed a high utilization of ophthalmological consultations, which could be based on the interdisciplinary guidelines for early detection of diabetic eye complications.


Ophthalmologists , Adolescent , Adult , Aged , Female , Germany , Health Surveys , Humans , Male , Middle Aged , Prevalence , Young Adult
13.
Reprod Biol Endocrinol ; 15(1): 96, 2017 Dec 16.
Article En | MEDLINE | ID: mdl-29246176

BACKGROUND: Several studies have reported a correlation between antral follicle count by conventional 2D transvaginal sonography and serum anti-Müllerian hormone levels. However, few studies have investigated the effectiveness of 3D SonoAVC transvaginal ultrasound technology, particularly in infertile women. Therefore, this study aims to evaluate the usefulness of three-dimensional (3D) SonoAVC transvaginal ultrasound technology for antral follicle count and its correlation to conventional two-dimensional (2D) transvaginal ultrasound and serum levels of anti-Müllerian hormone in infertile women. METHODS: This cross-sectional study included 42 infertile women with age lower than 40 years that underwent treatment at a private fertility clinic between June and December 2015. Patient data included age, body mass index and cause of infertility. On cycle day 3 the following hormone levels were measured: serum levels of anti-Müllerian hormone, follicle-stimulating hormone, cancer antigen 125, prolactin, thyroid-stimulating hormone and oestradiol; the number of antral follicles was counted as well. The scanning were performed through 2D and 3D technology transvaginal ultrasound. RESULTS: Using a Bland-Altman test we demonstrated that both technologies are quite equivalent. However, antral follicle count is higher using 3D ultrasound technology compared to 2D technology (p < 0.001; Wilcoxon test), this finding is mainly remarkable in ovaries with more than 20 antral follicles. Moreover, the mean time required for manual 2D ultrasound and 3D SonoAVC measurements were 275 ± 109 and 103 ± 57 s, respectively (p < 0.001). Serum AMH concentration correlated to the total number of early antral follicles (correlation coefficients = 0.678 and 0.612; p < 0.001 by 2D ultrasound and 3D SonoAVC, respectively; Spearman's correlation test). CONCLUSIONS: Antral follicle count is better estimated using 3D ultrasound compared to 2D technology. A great advantage of 3D SonoAVC was less time required for an examination and the visual advantage when it need to count more than 20 follicles. TRIAL REGISTRATION: CAAE: 35141114.4.0000.5327 . Registered 10 June 2015.


Anti-Mullerian Hormone/blood , Imaging, Three-Dimensional/methods , Infertility, Female/diagnostic imaging , Ovarian Follicle/diagnostic imaging , Ultrasonography/methods , Adult , Cross-Sectional Studies , Estradiol/blood , Female , Follicle Stimulating Hormone/blood , Humans , Infertility, Female/blood
14.
Klin Monbl Augenheilkd ; 231(7): 729-34, 2014 Jul.
Article De | MEDLINE | ID: mdl-24788605

BACKGROUND: The aim of this study was to compare two different surgical techniques for the therapy of senile entropion. PATIENTS AND METHODS: Our retrospective case series study included patients who were operated on for a senile entropion, either according to the technique described by Quickert or by surgery of the lateral tarsal strip in combination with resection of a part of the hypertrophic orbicularis muscle. All patients who had undergone entropion surgery according to one of the two procedures between 2008 and 2010 were contacted. Main outcome measures were patients' satisfaction and recurrence of entropion. RESULTS: The study included 38 patients (age: 75.5 ± 7.7 years) who could be contacted and who were able to perform a telephone interview; 13 of these patients were additionally examined clinically. Mean follow-up after surgery was 43.1 ± 5.6 months. 83 % were happy to do the operation again. There was no statistical difference in patients' satisfaction with the operations. The clinical examination showed two recurrences of entropion in the Quickert group and none in the lateral tarsal strip group. CONCLUSIONS: Quickert's operation and the lateral tarsal strip procedure in combination with resection of a part of the hypertrophic orbicularis muscle are efficient procedures for therapy of an entropion.


Blepharoplasty/methods , Entropion/surgery , Aged , Aged, 80 and over , Entropion/diagnosis , Entropion/etiology , Female , Humans , Male , Middle Aged , Postoperative Complications/etiology , Recurrence , Retrospective Studies
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