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1.
Mol Phylogenet Evol ; : 108144, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38972494

RESUMEN

Phylogenomic approaches have recently helped elucidate various insect relationships, but large-scale comprehensive analyses on relationships within sawflies and woodwasps are still lacking. Here, we infer the relationships and long-term biogeographic history of these hymenopteran groups using a large dataset of 354 UCE loci collected from 385 species that represent all major lineages. Early Hymenoptera started diversifying during the Early Triassic ∼249 Ma and spread all over the ancient supercontinent Pangaea. We recovered Xyeloidea as a monophyletic sister group to other Hymenoptera and Pamphilioidea as sister to Unicalcarida. Within the diverse family Tenthredinidae, our taxonomically and geographically expanded taxon sampling highlights the non-monophyly of several traditionally defined subfamilies. In addition, the recent removal of Athalia and related genera from the Tenthredinidae into the separate family Athaliidae is supported. The deep historical biogeography of the group is characterised by independent dispersals and re-colonisations between the northern (Laurasia) and southern (Gondwana) palaeocontinents. The breakup of these landmasses led to ancient vicariance in several Gondwanan lineages, while interchange across the Northern Hemisphere has continued until the Recent. The little-studied African sawfly fauna is likewise a diverse mixture of groups with varying routes of colonization. Our results reveal interesting parallels in the evolution and biogeography of early hymenopterans and other ancient insect groups.

2.
Ophthalmol Ther ; 13(6): 1601-1617, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615132

RESUMEN

INTRODUCTION: Simulation training is an important component of medical education. In former studies, diagnostic simulation training for direct and indirect funduscopy was already proven to be an effective training method. In this prospective controlled trial, we investigated the effect of simulator-based fundus biomicroscopy training. METHODS: After completing a 1-week ophthalmology clerkship, medical students at Saarland University Medical Center (n = 30) were block-randomized into two groups: The traditional group received supervised training examining the fundus of classmates using a slit lamp; the simulator group was trained using the Slit Lamp Simulator. All participants had to pass an Objective Structured Clinical Examination (OSCE); two masked ophthalmological faculty trainers graded the students' skills when examining patient's fundus using a slit lamp. A subjective assessment form and post-assessment surveys were obtained. Data were described using median (interquartile range [IQR]). RESULTS: Twenty-five students (n = 14 in the simulator group, n = 11 in the traditional group) (n = 11) were eligible for statistical analysis. Interrater reliability was verified as significant for the overall score as well as for all subtasks (≤ 0.002) except subtask 1 (p = 0.12). The overall performance of medical students in the fundus biomicroscopy OSCE was statistically ranked significantly higher in the simulator group (27.0 [5.25]/28.0 [3.0] vs. 20.0 [7.5]/16.0 [10.0]) by both observers with an interrater reliability of IRR < 0.001 and a significance level of p = 0.003 for observer 1 and p < 0.001 for observer 2. For all subtasks, the scores given to students trained using the simulator were consistently higher than those given to students trained traditionally. The students' post-assessment forms confirmed these results. Students could learn the practical backgrounds of fundus biomicroscopy (p = 0.04), the identification (p < 0.001), and localization (p < 0.001) of pathologies significantly better with the simulator. CONCLUSIONS: Traditional supervised methods are well complemented by simulation training. Our data indicate that the simulator helps with first patient contacts and enhances students' capacity to examine the fundus biomicroscopically.

3.
J Environ Manage ; 348: 119036, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37857223

RESUMEN

In western Canada, decades of oil-and-gas exploration have fragmented boreal landscapes with a dense network of linear forest disturbances (seismic lines). These seismic lines are implicated in the decline in wildlife populations that are adapted to function in unfragmented forest landscapes. In particular, anthropogenic disturbances have led to a decline of woodland caribou populations due to increasing predator access to core caribou habitat. Restoration of seismic lines aims to reduce the landscape fragmentation and stop the decline of caribou populations. However, planning restoration in complex landscapes can be challenging because it must account for a multitude of diverse aspects. To assist with restoration planning, we present a spatial network optimization approach that selects restoration locations in a fragmented landscape while addressing key environmental and logistical constraints. We applied the model to develop restoration scenarios in the Redrock-Prairie Creek caribou range in northwestern Alberta, Canada, which includes a combination of caribou habitat and active oil-and-gas and timber extraction areas. Our study applies network optimization at two distinct scales to address both the broad-scale restoration policy planning and project-level constraints at the level of individual forest sites. We first delineated a contiguous set of coarse-scale regions where restoration is most cost-effective and used this solution to solve a fine-scale network optimization model that addresses environmental and logistical planning constraints at the level of forest patches. Our two-tiered approach helps address the challenges of fine-scale spatial optimization of restoration activities. An additional coarse-scale optimization step finds a feasible starting solution for the fine-scale restoration problem, which serves to reduce the time to find an optimal solution. The added coarse-scale spatial constraints also make the fine-scale restoration solution align with the coarse-scale landscape features, which helps address the broad-scale restoration policies. The approach is generalizable and applicable to assist restoration planning in other regions fragmented by oil-and-gas activities.


Asunto(s)
Reno , Animales , Conservación de los Recursos Naturales , Ecosistema , Bosques , Alberta
4.
Ophthalmol Ther ; 12(4): 2171-2186, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37294522

RESUMEN

INTRODUCTION: Simulation training has an important role in medical education. In ophthalmology, simulation-based training has been shown to be significantly effective for surgical and diagnostic training in direct and indirect ophthalmoscopy. In this study, we analysed the effects of simulator-based slit lamp training. METHODS: In this prospective controlled trial, medical students in their eighth semester at Saarland University Medical Center (n = 24) who had attended a 1-week ophthalmological internship were randomized into two groups: The traditional group (n = 12) was examined directly after the 1-week internship; the simulator group (n = 12) was trained with the slit lamp simulator before passing an objective structured clinical examination (OSCE). A masked ophthalmological faculty trainer assessed the students' slit lamp skills (maximum total score 42 points [pts]): preparation (5 pts), clinical examination (9.5 pts), assessment of findings (9.5 pts), diagnosis (3 pts), commentary on the examination approach (8 pts), measurement of structures (2 pts) and recognition of five diagnoses (5 pts). All students completed post-assessment surveys. Examination grades and survey responses were compared between the groups. RESULTS: The overall performance of the slit lamp OSCE was significantly better (p < 0.001) in the simulator group than in the traditional group (29.75 [7.88] vs. 17.00 [4.75]) with significantly higher scores for the preparation and assessment of slit lamp controls (5.0 [0.0] vs. 3.0 [3.5]; p = 0.008) and localization of relevant structures (6.75 [3.13] vs. 4.0 [1.5]; p = 0.008). Consistently higher scores, but not significant, were assigned for the description of structures found (4.5 [3.38] vs. 3.25 [2.13]; p = 0.09) and the correct diagnosis (3.0 [0.0] vs. 3.0 [0.0]; p = 0.48). Surveys reflected the students' subjectively perceived knowledge gain during the simulator training for slit lamp illumination techniques (p = 0.002), recognition (p < 0.001), and assessment of the correct localization of pathologies (p < 0.001). CONCLUSION: Slit lamp examination is an important diagnostic method in ophthalmology. Simulator-based training improved students' examination techniques for localizing anatomical structures and pathological lesions. The transfer of theoretical knowledge into practice can be achieved in a stress-free atmosphere.

5.
Sci Rep ; 13(1): 3666, 2023 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-36871063

RESUMEN

Forests across much of the United States are becoming denser. Trees growing in denser stands experience more competition for essential resources, which can make them more vulnerable to disturbances. Forest density can be expressed in terms of basal area, a metric that has been used to assess vulnerability of some forests to damage by certain insects or pathogens. A raster map of total tree basal area (TBA) for the conterminous United States was compared with annual (2000-2019) survey maps of forest damage due to insects and pathogens. Across each of four regions, median TBA was significantly higher within forest areas defoliated or killed by insects or pathogens than in areas without recorded damage. Therefore, TBA may serve as a regional-scale indicator of forest health and a first filter for identifying areas that merit finer-scale analysis of forest conditions.


Asunto(s)
Bosques , Insectos , Animales , Registros , Árboles
7.
Br J Ophthalmol ; 107(10): 1502-1508, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-35840291

RESUMEN

BACKGROUND: The ILUVIEN Registry Safety Study was a multicentre, open-label, non-randomised, observational, phase 4 study designed to assess the safety and effectiveness of the fluocinolone acetonide (FAc) implant in all indications in real-world practices in Europe. METHODS: The study included data collected prospectively and retrospectively. Patients receiving FAc implants between 2013 and 2017 were included and monitored until the last patient reached ≥3 years of follow-up. Mean intraocular pressure (IOP) data over the course of the study, along with IOP events, use of IOP-lowering therapy, mean change in visual acuity (VA) and information on supplemental therapy use were analysed post-FAc implantation. RESULTS: Six hundred and ninety-five eyes from 556 patients, with a mean±SD follow-up of 1150.5±357.36 days, were treated with a FAc implant. 96.7% of eyes had chronic diabetic macular oedema (cDMO). IOP lowering was achieved in 34.5% of eyes using topical agents and 4.3% by surgery. Seventy-three eyes (64.6% of 113 phakic) required cataract surgery during follow-up. Mean VA increased from a baseline of 52.2 letters to 57.1 letters at month 36, with improvement observed up to month 48. Supplementary therapies were given in 43.7% of eyes. When classified by length of cDMO less than or greater than the median duration those with a shorter history experienced greater VA gains than those with a longer history. CONCLUSION: This study confirms the favourable, long-term benefit-to-risk profile of the FAc implant in eyes with cDMO, with an additional benefit in patients when this therapy is administered earlier.


Asunto(s)
Retinopatía Diabética , Edema Macular , Humanos , Fluocinolona Acetonida , Glucocorticoides/uso terapéutico , Edema Macular/tratamiento farmacológico , Estudios Retrospectivos , Implantes de Medicamentos , Inyecciones Intravítreas , Iris
8.
Clin Ophthalmol ; 16: 3711-3720, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36389636

RESUMEN

Introduction: To investigate the safety and efficacy of the Vitesse hypersonic vitrectomy device for retinal reattachment surgery in proliferative vitreoretinopathy (PVR) or proliferative diabetic vitreoretinopathy (PDVR) cases. The Vitesse device utilizes hypersonic technology to liquefy instead of cutting the vitreous, providing an alternative to the traditional pneumatic guillotine cutter. Material and Methods: A prospective, one-armed, non-comparative, open-label study was performed. Sixteen patients with a diagnosis of PVR or PDVR that required retinal reattachment surgery were included. Severity of disease was classified using the Retina Society 1983 classification and Kroll Classification from 2007. Patient data was collected preoperatively, 2 days postoperatively, 1 month postoperatively, and 3 months postoperatively. Efficacy of hypersonic vitrectomy was evaluated, both subjectively using a questionnaire and objectively by means of Supplementary Video documentation, device settings, and data collection of the patients' medical history. Results: In all 16 cases, retinal reattachment surgery could be performed with Vitesse without conversion to a guillotine cutter. The vitreous could be separated from the detached retina completely with no iatrogenic tissue damage. Vitreous traction was documented in one case. In 6 cases, shaving of the vitreous base was performed after early fluid-air exchange with hypersonic vitrectomy without any complications. No adverse events suspected to be related to hypersonic vitrectomy were documented in the follow-up visits. Conclusion: The Vitesse has potential advantages including reduced vacuum volumes with limited amount of turbulence and avoidance vitreoretinal traction. Liquefaction directly in front of the probe entrance allows for continuous unrestricted fluid flow. These factors of hypersonic technology allow to carry out retinal reattachment surgery in PVR or PDVR cases successfully.

9.
BMC Med Educ ; 22(1): 599, 2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35922857

RESUMEN

BACKGROUND: Microsurgery is a growing field which requires significant precision and skill. Eyesi Surgical, which is usually introduced during residency or fellowship, is an ophthalmologic microsurgery simulator which allows users to practice abstract microsurgical skills and more specialized skills. The purpose of this study was to assess the inclusion of microsurgical simulation training during medical school. METHODS: Seventy-nine German medical students in their 10th semester of education completed up to two days of training on the simulator during their ophthalmology clerkship. They received an objective numeric score based on simulator performance and completed pre and post training subjective questionnaires. RESULTS: There was no relationship found between students' Eyesi Surgical performance scores and their specialty interests (p = .8). The majority of students (73.4%) rated their microsurgical skills to be higher after simulator training than before training (p < 0.001). 92.4% of students found the Eyesi Surgical to be a useful component of the ophthalmology clerkship. Objective scores from Navigation Training Level 1 showed that students achieved better results in the criteria categories of Completing Objects and Tissue Treatment than in the categories of Instrument and Microscope Handling. The mean Total Score was 25.7 (± 17.5) out of a possible 100 points. CONCLUSION: The inclusion of surgical simulation in the ophthalmology clerkship led to increased confidence in the microsurgical skills of medical students. Offering surgical simulation training prior to residency can help to expose students to surgical fields, identify those that have particular talent and aptitude for surgery, and assist them in deciding which specialty to pursue.


Asunto(s)
Internado y Residencia , Oftalmología , Entrenamiento Simulado , Estudiantes de Medicina , Competencia Clínica , Simulación por Computador , Alemania , Humanos , Microcirugia , Oftalmología/educación , Estudios Prospectivos , Entrenamiento Simulado/métodos
10.
Am J Ophthalmol ; 244: 166-174, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35853490

RESUMEN

PURPOSE: To evaluate formulas for intraocular lens (IOL) calculation in silicone oil (SO)-filled eyes. DESIGN: Retrospective, consecutive case series. METHODS: We conducted our study at the Department of Ophthalmology, Goethe University, Frankfurt, Germany, and included SO-filled eyes that received SO removal combined with phacoemulsification and IOL implantation. Preoperative assessments included biometry (IOLMaster 700; Carl Zeiss Meditec). To evaluate the measurements, we compared the mean prediction error, and mean and median absolute prediction error of 8 different formulas. RESULTS: A total of 90 eyes matched our inclusion criteria. The median absolute error was lowest in the Barrett Universal II formula (0.43 diopters [D] ± 0.75) followed by Kane (0.44 D ± 0.75), Hill-radial basis function (0.47 D ± 0.74), Holladay II (0.47 D ± 0.77), Sanders Retzlaff Kraff/theoretical (0.51 D ± 0.74), Holladay I (0.51 D ± 0.76), and Haigis and Hoffer Q (0.52 D ± 0.74 each). Regarding eyes within ±0.5 D Barrett Universal II (57.8%, 52 eyes) performed best, again followed by Kane (56.7%, 51 eyes) and Hill-radial basis function (54.4%, 49 eyes). CONCLUSION: Using modern formulas for IOL calculation in oil-filled eyes improves predictability but still not as good as in unoperated eyes. This issue is created by the change in refractive index due to the SO fill and therefore a lower precision of axial length measurement and effective lens position prediction.


Asunto(s)
Lentes Intraoculares , Facoemulsificación , Desprendimiento de Retina , Humanos , Aceites de Silicona , Desprendimiento de Retina/cirugía , Implantación de Lentes Intraoculares , Estudios Retrospectivos , Refracción Ocular , Óptica y Fotónica , Agudeza Visual , Biometría , Longitud Axial del Ojo
11.
Graefes Arch Clin Exp Ophthalmol ; 260(8): 2537-2547, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35239010

RESUMEN

PURPOSE: To investigate the changes in vitreous inflammatory and angiogenic cytokine levels, primarily interleukin-(IL)-6, following intravitreal injection of the 0.19 mg fluocinolone acetonide (FAc, ILUVIEN®) implant in patients with diabetic macular edema. METHODS: A single-center phase IV study involving 12 patients' eyes with diabetic macular edema. Vitreous fluid samples were obtained prior to intravitreal injection of the fluocinolone acetonide implant and then again over a 6-month period. Vitreous samples were examined using a cytometric bead array to measure IL-6, IL-8, IP-10, MCP-1, VEGF, and CD54. PIGF and PEDF were measured using an enzyme-linked immunosorbent assay. Changes in the cytokine and chemokine expression patterns were analyzed. Clinical parameters such as BCVA and center point thickness (CPT) were also examined. RESULTS: There were mean reductions in all parameters between baseline and month 6. Significant changes (p < 0.05 versus baseline) were observed in the expression of IL-6, IP-10, MCP-1, and CD54 following the administration of fluocinolone acetonide implant. VEGF and PIGF increased at month 1 before declining at month 6, though this trend was not significant. CPT decreased rapidly between screening and the first follow-up visit, and this decrease was sustained. BCVA remained relatively stable throughout. CONCLUSION: This study demonstrated changes in vitreous inflammatory and angiogenic cytokine levels following intravitreal injection of the FAc implant in patients with diabetic macular edema. Data show that the fluocinolone acetonide implant led to rapid and sustained reductions of some inflammatory cytokines with improvement of the overall clinical picture.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Quimiocina CXCL10/uso terapéutico , Citocinas , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/tratamiento farmacológico , Implantes de Medicamentos/uso terapéutico , Femenino , Fluocinolona Acetonida , Glucocorticoides , Humanos , Interleucina-6 , Inyecciones Intravítreas , Edema Macular/diagnóstico , Edema Macular/tratamiento farmacológico , Edema Macular/etiología , Factor de Crecimiento Placentario/uso terapéutico , Factor A de Crecimiento Endotelial Vascular , Agudeza Visual
12.
Ophthalmologe ; 119(1): 20-29, 2022 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-33449201

RESUMEN

BACKGROUND: Ophthalmoscopy is part of the medical curriculum but the teaching of medical contents is often unsatisfactory. No systematic learning of pathologies and their treatment options is possible because appropriate patient populations are often unavailable; instead of that healthy students examine each other. For this reason, we have developed a project to improve teaching at the medical faculty of the JWG University in Frankfurt/Main, which offers the opportunity for training in ophthalmoscopy using a newly developed online platform (EyesiNet) in addition to simulator training. Defined learning contents are reproducible and made equally available to everyone. AIM: The aim of this study was to evaluate a format for improving the teaching of direct and indirect ophthalmoscopy for students. Practical exercises on virtual reality-based simulators were intertwined with newly developed theoretical content adapted to the teaching catalog in the online platform EyesiNet. MATERIAL AND METHODS: On the first and last days of the internship, the students worked on cases in Eyesi Direct and Eyesi Indirect. In the meantime, they were able to deal with the theoretical basics of these ophthalmological clinical pictures in the web-based EyesiNet on a voluntary basis. RESULTS: Eyesi Direct: with p = 0.29, both groups had the same state of knowledge and did not have significantly different results in case processing on the first day of the internship. In the group without training (n = 54), a significant improvement in simulator training was observed on the last day of the practical training with p = 0.02 but with a small effect size of 0.1. Among the trainees (n = 32) a highly significant improvement with an effect size of 0.3 was observed with p = 0.0004. Eyesi Indirect: both groups had no significant difference in the stage of knowledge in the Eyesi Indirect at the beginning of the training period (p = 0.10). After training both groups performed slightly better but without significance (without training p = 0.41/with training p = 0.17). CONCLUSION: The online platform EyesiNet supports the learning of the most important disease patterns. Learning contents are made available in a reproducible and standardized way for all students. The skills of direct ophthalmoscopy can be learned much faster than those of indirect ophthalmoscopy.


Asunto(s)
Educación a Distancia , Oftalmología , Competencia Clínica , Simulación por Computador , Humanos , Oftalmología/educación , Estudiantes
13.
PLoS One ; 16(10): e0258060, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34618859

RESUMEN

Although wildfires are an important ecological process in forested regions worldwide, they can cause significant economic damage and frequently create widespread health impacts. We propose a network optimization approach to plan wildfire fuel treatments that minimize the risk of fire spread in forested landscapes under an upper bound for total treated area. We used simulation modeling to estimate the probability of fire spread between pairs of forest sites and formulated a modified Critical Node Detection (CND) model that uses these estimated probabilities to find a pattern of fuel reduction treatments that minimizes the likely spread of fires across a landscape. We also present a problem formulation that includes control of the size and spatial contiguity of fuel treatments. We demonstrate the approach with a case study in Kootenay National Park, British Columbia, Canada, where we investigated prescribed burn options for reducing the risk of wildfire spread in the park area. Our results provide new insights into cost-effective planning to mitigate wildfire risk in forest landscapes. The approach should be applicable to other ecosystems with frequent wildfires.


Asunto(s)
Ecosistema , Bosques , Parques Recreativos , Incendios Forestales/prevención & control , Colombia Británica , Simulación por Computador , Humanos
15.
PLoS One ; 16(5): e0248439, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34010297

RESUMEN

Diabetic retinopathy (DR) is an inflammatory condition that affects the posterior of the eye; yet, there are limited published data on techniques measuring the expression of growth and inflammatory factors (GIF) from the posterior segment. The purpose of the current study was two-fold: to sample the vitreous fluid from the eyes of patients with DR and assess the expression of GIF. As DR is an inflammatory disease, the second objective of this study was to determine the relationship between the status of DR and the expression of vitreous GIF. This non-randomized clinical trial was approved by BfARM for the analysis and evaluation of 12 eyes from patients with diabetic macular edema. Vitreous sampling was performed before treatment with fluocinolone acetonide and the extracted vitreous material was examined for the determination of GIF including interleukins 6 (IL-6) and 8 (IL-8), interferon gamma-inducible protein (IP-10), monocyte chemoattractant protein-1 (MCP-1), placental growth factor (PIGF), pigment epithelium-derived factor (PEDF), VEGF (vascular endothelial growth factor) and intercellular adhesion molecule (CD54). These were linearly compared with the grade of inflammation in the vitreous assessed via DR score and ART. Additionally, all eyes were grouped based on their diabetic retinopathy status. All cytokine levels, except MCP-1 and PEDF, were numerically higher in DME patients with proliferative DR than those with non-proliferative DR. DR grade was found to linearly correlate with the expression of CD54 (p = 0.02, rho = 0.64), IL-8 (p = 0.03, rho = 0.64) and PIGF (p = 0.007, rho = 0.76). A correlation was found between ART and CD54 (p = 0.02, rho = 0.66) and also between ART and IL-8 (p = 0.04, rho = 0.60). A trend was found between ART and PIGF (p = 0.08, rho 0.52). For IL-6, there appeared to be a trend with DR grade (p = 0.14, rho = 0.45) and ART (p = 0.09, rho = 0.51). Proliferative DR was shown to be associated with a significant higher expression of CD54, IL-8 and PIGF, thus suggesting that they are potentially important in defining and monitoring the effectiveness of a patients' therapy. Vitreous probes may be helpful in deciding which therapy to administer (i.e. anti-VEGF or corticosteroid or both) based on the expression of GIF. Registry EudraCT number: 2016-004488-38; DRKS-ID: DRKS00014915.


Asunto(s)
Citocinas/metabolismo , Retinopatía Diabética/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Cuerpo Vítreo/metabolismo , Adulto , Anciano , Biomarcadores/metabolismo , Citocinas/genética , Retinopatía Diabética/patología , Femenino , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Masculino , Persona de Mediana Edad , Cuerpo Vítreo/patología
16.
Ophthalmologe ; 118(7): 741-746, 2021 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-33877403

RESUMEN

In the 1970s a cutting device into which an infusion and an aspiration channels were integrated, the so-called vitreous infusion suction cutter (V.I.S.C), was used for the first time for the removal of the vitreous body. These cutting systems have continued to constantly evolve since then; however, sonic energy remained reserved for anterior segment surgery for a long time. In 2020, this form of energy could also be used for the posterior segment in form of Vitesse™. In this liquification technique, ultrasonic energy is transferred to a single, large inner lumen design that mechanically vibrates the needle's port. These high-speed vibrations shear the vitreous body at the port edges before it enters the needle. This mechanism reduces traction to a minimal level and enables faster aspiration at lower vacuum levels compared to conventional cutters. These advantages can promote a safer and more efficient vitreoretinal surgery.


Asunto(s)
Vitrectomía , Cuerpo Vítreo , Humanos , Microcirugia , Succión , Tecnología , Cuerpo Vítreo/cirugía
17.
Ophthalmologe ; 118(1): 56-59, 2021 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-32274532

RESUMEN

After an uneventful intravitreal injection (IVI) of Ocriplasmin in a patient with reduced visual acuity due to vitreomacular traction (VMT) and a small macular hole, retinal detachment occurred within a few days after the operation. Although retinal detachment is known as a risk factor of IVI this case is noteworthy: an excessive reaction occurred in the region of the vitreous body, which resulted in the development of severe traction on the retina leading to a posterior vitreous body detachment, retinal holes and complete retinal detachment. This possible complication should be discussed in the preoperative patient informed consent and the reason for this excessive reaction should be the subject of further investigations.


Asunto(s)
Desprendimiento de Retina , Perforaciones de la Retina , Desprendimiento del Vítreo , Fibrinolisina/efectos adversos , Humanos , Inyecciones Intravítreas , Fragmentos de Péptidos/efectos adversos , Desprendimiento de Retina/inducido químicamente , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/tratamiento farmacológico , Perforaciones de la Retina/inducido químicamente , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/tratamiento farmacológico , Adherencias Tisulares/tratamiento farmacológico , Agudeza Visual , Desprendimiento del Vítreo/inducido químicamente , Desprendimiento del Vítreo/tratamiento farmacológico
18.
Emerg Top Life Sci ; 4(5): 513-520, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33241845

RESUMEN

When alien species make incursions into novel environments, early detection through surveillance is critical to minimizing their impacts and preserving the possibility of timely eradication. However, incipient populations can be difficult to detect, and usually, there are limited resources for surveillance or other response activities. Modern optimization techniques enable surveillance planning that accounts for the biology and expected behavior of an invasive species while exploring multiple scenarios to identify the most cost-effective options. Nevertheless, most optimization models omit some real-world limitations faced by practitioners during multi-day surveillance campaigns, such as daily working time constraints, the time and cost to access survey sites and personnel work schedules. Consequently, surveillance managers must rely on their own judgments to handle these logistical details, and default to their experience during implementation. This is sensible, but their decisions may fail to address all relevant factors and may not be cost-effective. A better planning strategy is to determine optimal routing to survey sites while accounting for common daily logistical constraints. Adding site access and other logistical constraints imposes restrictions on the scope and extent of the surveillance effort, yielding costlier but more realistic expectations of the surveillance outcomes than in a theoretical planning case.


Asunto(s)
Especies Introducidas , Análisis Costo-Beneficio
20.
Z Med Phys ; 30(3): 201-210, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32143979

RESUMEN

PURPOSE: For transscleral application of optical radiation or light to the eye, it is important to know the transmission and absorbance of the tissue layers of the eyewall. The impact of photochemical energy to the retina located directly at the point of contact with the radiation emitter must be considered as well as the absorbance in choroid and retina. Therefore, the direct transmission of ex vivo porcine eyewalls and vitreous body were measured in this study. METHODS: At ex vivo porcine eyes (N=221) pressure dependent transmission measurements were performed with a pressure inducing setup. Pressure and wavelength dependent direct transmission of eyewall and vitreous body of porcine eyes were described for different applied pressures (23mmHg, 78mmHg and 132mmHg). The transmissions were investigated within the spectral range of 350-1050nm. In addition to the complete eyewall transmission measurements, the transmission of sclera, vitreous body and water was measured individually and the transmission of retina and choroid was calculated. RESULTS: With increasing wavelength and pressure, a significant transmission increase of the eyewall could be achieved (p<0.05). At 400nm and 132mmHg the transmission raised to 0.10%. At 1050nm it increased up to a value of 12.22%. In the visible spectrum, the direct transmission was always below 3.17%. The differences in eyewall transmission of eyes with different iris colors were significant at low pressure. With increasing pressure, the effect strength decreased and the differences lost their significance. CONCLUSIONS: The pressure and wavelength dependent direct transmission of the eyewall and the vitreous body significantly increased with increasing pressure. This results are benefical for technical and clinical safety, research and development of illumination devices. It is necessary to know the intraocular brightness in the eye during diaphanoscopy, photocoagulation application to determine hazards.


Asunto(s)
Presión , Esclerótica/fisiología , Cuerpo Vítreo/fisiología , Animales , Porcinos
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