Raffael Liegl

Dr. Raffael Liegl


Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 October 2018 in JCI Insight
Verified
Journal Article
Open access
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BCBertan Cakir
Bertan Cakir
RLRaffael Liegl
Raffael Liegl
GHGunnel Hellgren
Gunnel Hellgren
Pia LundgrenPia Lundgren
Pia Lundgren
YSYe Sun
Ye Sun
AHAnn Hellström
Ann Hellström
Retinopathy of prematurity (ROP) is characterized by abnormal retinal neovascularization in response to vessel loss. Platelets regulate angiogenesis and may influence ROP progression. In preterm infants, we assessed ROP and correlated with longitudinal postnatal platelet counts ( n = 202). Any episode of thrombocytopenia (<100 × 10 9 /l) at ≥30 weeks postmenstrual age (at onset of ROP) was independently associated with severe ROP, requiring treatment. Infants with severe ROP also had a lower weekly median platelet count compared with infants with less severe ROP. In a mouse oxygen-induced retinopathy model of ROP, platelet counts were lower at P17 (peak neovascularization) versus controls. Platelet transfusions at P15 and P16 suppressed neovascularization, and platelet depletion increased neovascularization. Platelet transfusion decreased retinal of vascular endothelial growth factor A (VEGFA) mRNA and protein expression; platelet depletion increased retinal VEGFA mRNA and protein expression. Resting platelets with intact granules reduced neovascularization, while thrombin-activated degranulated platelets did not. These data suggest that platelet releasate has a local antiangiogenic effect on endothelial cells to exert a downstream suppression of VEGFA in neural retina. Low platelet counts during the neovascularization phase in ROP is significantly associated with the development of severe ROP in preterm infants. In a murine model of retinopathy, platelet transfusion during the period of neovascularization suppressed retinopathy.

2 October 2020 in JCI Insight
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Journal Article
Open access
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BCBertan Cakir
Bertan Cakir
WHWilliam Hellström
William Hellström
Yohei TomitaYohei Tomita
Yohei Tomita
ZFZhongjie Fu
Zhongjie Fu
RLRaffael Liegl
Raffael Liegl
LSLois Smith
Lois Smith
BACKGROUND: Hyperglycemia, insulin insensitivity, and low IGF1 levels in extremely preterm infants are associated with an increased risk of retinopathy of prematurity (ROP), but the interactions are incompletely understood. METHODS: In 117 extremely preterm infants, serum glucose levels and parenteral glucose intake were recoded daily in the first postnatal week. Serum IGF1 levels were measured weekly. Mice with oxygen-induced retinopathy alone versus oxygen-induced retinopathy plus streptozotocin-induced hyperglycemia/hypoinsulinemia were assessed for glucose, insulin, IGF1, IGFBP1, and IGFBP3 in blood and liver. Recombinant human IGF1 was injected to assess the effect on glucose and retinopathy. RESULTS: The highest mean plasma glucose tertile of infants positively correlated with parenteral glucose intake [r (39) = 0.67, P < 0.0001]. IGF1 plasma levels were lower in the high tertile compared with those in low and intermediate tertiles at day 28 ( P = 0.038 and P = 0.03). In high versus lower glucose tertiles, ROP was more prevalent (34 of 39 versus 19 of 39) and more severe (ROP stage 3 or higher; 71% versus 32%). In oxygen-induced retinopathy, hyperglycemia/hypoinsulinemia decreased liver IGF1 expression ( P < 0.0001); rh-IGF1 treatment improved normal vascular regrowth ( P = 0.027) and reduced neovascularization ( P < 0.0001). CONCLUSION: In extremely preterm infants, high early postnatal plasma glucose levels and signs of insulin insensitivity were associated with lower IGF1 levels and increased ROP severity. In a hyperglycemia retinopathy mouse model, decreased insulin signaling suppressed liver IGF1 production, lowered serum IGF1 levels, and increased neovascularization. IGF1 supplementation improved retinal revascularization and decreased pathological neovascularization. The data support IGF1 as a potential treatment for prevention of ROP. TRIAL REGISTRATION: ClinicalTrials.gov NCT02760472 (Donna Mega). FUNDING: This study has been supported by the Swedish Medical Research Council (14940, 4732, 20144-01-3, and 21144-01-3), a Swedish government grant (ALFGB2770), Lund medical faculty grants (ALFL, 11615 and 11601), the Skåne Council Foundation for Research and Development, the Linnéa and Josef Carlsson Foundation, the Knut and Alice Wallenberg Foundation, the NIH/National Eye Institute (EY022275, EY017017, EY017017-13S1, and P01 HD18655), European Commission FP7 project 305485 PREVENT-ROP, Deutsche Forschungsgemeinschaft (CA-1940/1-1), and Stiftelsen De Blindas Vänner.

13 January 2023 in American Journal of Ophthalmology
Verified
Journal Article
Closed access
RLRaffael Liegl
Raffael Liegl
VSValerie Schmelter
Valerie Schmelter
CFChristoph Fuerweger
Christoph Fuerweger
FEFelix Ehret
Felix Ehret
SPSiegfried Priglinger
Siegfried Priglinger
PFPaul Foerster
Paul Foerster

8 February 2020 in Journal of Cancer Research and Clinical Oncology
Verified
Journal Article
Open access
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TSTheresa Steeb
Theresa Steeb
KHKinan M. Hayani
Kinan M. Hayani
PFPaul Förster
Paul Förster
RLRaffael Liegl
Raffael Liegl
FTFrédéric Toussaint
Frédéric Toussaint
MHMarkus V Heppt
Markus V Heppt
Purpose: Clinical practice guidelines provide recommendations for the management of diseases. In orphan conditions such as uveal melanoma (UM), guideline developers are challenged to provide practical and useful guidance even in the absence of high-quality evidence. Here, we assessed the methodological quality and identified deficiencies of international guidelines on UM as a base for future guideline development. Methods: A systematic search was carried out in guideline databases, Medline and Embase until 27th May 2019 for guidelines on UM published between 2004 and 2019. Five independent reviewers assessed the methodological quality of the identified guidelines using the instruments “Appraisal of Guidelines for Research and Evaluation II” (AGREE II) and AGREE-REX (Recommendation EXcellence). Descriptive analysis was performed and subgroup differences were explored with the Kruskal–Wallis (H) test. The relationship between the individual domains and items of the instruments were examined using Spearman’s correlation. Results: Five guidelines published from 2014 to 2018 by consortia of the United States of America, Canada and the United Kingdom (UK) were included. The highest scores were obtained by the UK guideline fulfilling 48–86% of criteria in AGREE II and 30–60% for AGREE-REX. All guidelines showed deficiencies in the domains “editorial independence”, “applicability”, and “recommendation”. Subgroup differences were identified only for the domain “editorial independence”. Conclusion: The UK guideline achieved the highest scores with both instruments and may serve as a basis for future guideline development in UM. The domains “editorial independence”, “recommendation”, and “applicability” were identified as methodological weaknesses and require particular attention and improvement in future guidelines.

13 November 2013 in Ophthalmologica
Verified
Journal Article
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RLRaffael Liegl
Raffael Liegl
KLKristine Liegl
Kristine Liegl
LCLala Ceklic
Lala Ceklic
CHChristos Haritoglou
Christos Haritoglou
AKAnselm Kampik
Anselm Kampik
ANAljoscha S. Neubauer
Aljoscha S. Neubauer
The purpose of this study was to investigate the diagnostic properties of a 2-laser wavelength nonmydriatic 200° ultra-wide-field scanning laser ophthalmoscope (SLO) versus mydriatic 2-field 45° color fundus photography (EURODIAB standard) for assessing diabetic retinopathy (DR). A total of 143 consecutive eyes of patients with different levels of DR were graded regarding DR level and macular edema based on 2-field color photographs or 1 Optomap Panoramic 200 SLO image. All SLO images were nonmydriatic and all photographs mydriatic. Grading was performed masked to patient and clinical data. Based on photography, 20 eyes had no DR, 44 had mild, 18 moderate and 42 severe nonproliferative DR, and 19 eyes had proliferative DR. Overall correlation for grading DR level compared to Optomap SLO was moderate with kappa 0.54 (p < 0.001), fair-to-moderate in macular edema grading with kappa 0.39 (p < 0.001), and substantial for grading clinically significant macular edema (kappa 0.77). The wide-field SLO offers a wider field of view and can potentially better differentiate lesions by applying the 2 laser wavelengths. However, these advantages over 2-field fundus photography need to be confirmed in further studies.

29 November 2022 in Graefe's Archive for Clinical and Experimental Ophthalmology
Verified
Journal Article
Open access
PDF file
CWConstance Weber
Constance Weber
MBMaria Bertelsmann
Maria Bertelsmann
ZKZoe Kiy
Zoe Kiy
ISIsabel Stasik
Isabel Stasik
FHFrank G. Holz
Frank G. Holz
RLRaffael Liegl
Raffael Liegl
Purpose: Patients with extensive submacular hemorrhage (SMH) caused by age-related macular degeneration (AMD) have a poor visual prognosis despite surgical intervention. Systemic blood-thinning drugs, which are commonly prescribed in the same age group, are known to increase the risk of severe hemorrhage in many parts of the body. This study aimed to investigate whether systemic blood-thinning drugs have an impact on the severity of SMH and if there are differences between the different types of blood-thinning medication. Methods: We reviewed the medical records of patients who suffered from surgically treated SMH between 2020 and 2022. All patients received a full ophthalmologic examination upon presentation including best-corrected visual acuity (BCVA) and optical coherence tomography. Other characteristics that were recorded included size of hemorrhage, blood-thinning therapy, and reason for intake. Results: A total of 115 patients with a mean age of 82 years were included in this retrospective analysis. Eighty-three patients (72.2%) were on blood-thinning therapy. The mean size of SMH was 32.01 mm2. Mean BCVA at initial presentation was 1.63 logMAR and 1.59 logMAR 1 year after surgery. The size of SMH was significantly larger in patients on blood-thinning medication (35.92 mm2 vs. 21.91 mm2) (p = 0.001) and their BCVA postoperatively was worse with 1.68 logMAR compared to 1.30 logMAR after 1 year (p = 0.503). Patients with vitamin K antagonists had larger SMH size and worse outcomes regarding BCVA compared to direct oral anticoagulants. Conclusion: Blood thinners in patients with AMD affect the severity of SMH. Consequently, the indication for their intake should be critically evaluated.