The department of ophthalmology performs the complete range of ophthalmological surgery with special expertise in surgery of cataract, vitreous body, cornea, glaucoma, and the retina. For these procedures advanced diagnostics and special ophthalmologic lasers (argon laser, diode laser, Nd:YAG laser, Erbium-YAG-laser, CO2 laser) are available. Our focus of research is the functional and molecular imaging of the retina with measurement of blood flow changes, oxygen saturation, and fluorescence lifetimes (FLIO). The latter is supported by the availability of a prototype device manufactured by Heidelberg Engineering. Furthermore, a new device for the measurement of optic disk hemoglobin concentration and oxygenation was developed in cooperation with Imedos Systems GmbH. Currently, this new technique is under clinical testing for glaucoma diagnostics.

Prof. Dr. Daniel Meller
Am Klinikum
07747 Jena

Ophthalmology

Research projects

Natural history of activated retinal pigment epithelium and its role in age-related macular degeneration progression

Principal investigator: Dr. Martin Hammer
2016 - 2021

In age-related macular degeneration (AMD), activation and migration of retinal pigment epithelium (RPE) precedes its atrophy and, thus, might be a therapeutic target. We use fluorescence lifetime ophthalmoscopy FLIO, developed in our lab and now available from Heidelberg Engineering GmbH) to characterize activation, migration, and transdifferentiation of RPE cells in clinical imaging of AMD patients in a longitudinal observational study.

Experimental and clinical investigations for the spectral measurement of blood concentration and oxygen saturation at the ocular fundus

Principal investigator: Dr. Rowena Schultz
Thüringer Aufbaubank 2017 - 2020

The analysis of retinal vascular function is an important diagnostic technique. This project aims for a quantitative measurement of blood volume and oxygen saturation in capillarized tissue. The technique is currently under clinical testing for glaucoma diagnostics. Differences of optic disk hemoglobin concentration and oxygen saturation in glaucoma vs. controls as well as their correlation with OCT-angiography measures of blood flow are investigated.

Investigation of oxygen saturation and blood flow regulation under Aflibercept therapy in various forms of diabetic retinopathy with diabetic macular edema

Principal investigator: Dr. Somar Hasan
2016 - 2019

The VEGF antibody Aflibercept is approved for the treatment of diabetic macular edema since 2015. This pilot study investigated whether Aflibercept improves local blood flow regulation and oxygen supply. Patients were followed for one year and vessel diameters and hemoglobin oxygen saturation as well as their change under neuronal stimulation are measured.

In vitro investigation of the intrinsic fluorescence of retinal metabolic byproducts contributing to AMD pathogenesis

Principal investigator: Dr. Rowena Schultz
2018 - 2023

FLIO is able to study molecular fluorescence properties (lifetimes) of metabolic byproducts, contributing to the pathogenesis of AMD, in vivo. Here we study the generation and the fluorescence spectra and lifetimes of these byproducts generated in transwell and speroid cultures of RPE cells. Goal is the correct interpretation of clinical FLIO data and the better understanding of AMD pathogenesis.

Impact of lens fluorescence on the FLIO measurement retinal fluorescence lifetimes and mathematical models for its compensation

Principal investigator: Dr. Martin Hammer
2020 - 2022

Lens fluorescence is a crucial confounder in FLIO measurements. Its impact was determined by the measurements in patients pre and post cataract extraction. A mathematical model was developed which compensates for lens influence on retinal lifetime measurements. The applicability of this model to subjects other than elderly patients with cataract is tested now.

Further projects

FLIO for papillary drusen

Principal investigator: Dr. Martin Hammer

2019 – 2021
Retinal vessel analysis in mice

Principal investigator: Dr. Rowena Schultz

2018 - 2020
Transcranial alternating current stimulation for the improvement of retinal perfusion in glaucoma

Principal investigator: Dr. Martin Hammer

2020 - 2023
Hyperspectral Fundus Autofluorescence Imaging in AMD

Principal investigator: Dr. Martin Hammer

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Retinal perfusion in glaucoma under medical or surgical reduction of the intraocular pressure

Principal investigator: Dr. Somar Hasan

2019 - 2022
Fluorescence spectra and lifetimes in histology using 2-photon microscopy

Principal investigator: Dr. Rowena Schultz

2019 - 2021
Retinal venous pressure as a source of reduced perfusion pressure in glaucoma

Principal investigator: Dr. Somar Hasan

2019 - 2022

Selected publications

Hammer M, Schultz R, Hasan S, et al. Fundus Autofluorescence Lifetimes and Spectral Features of Soft Drusen and Hyperpigmentation in Age-Related Macular Degeneration. Translational vision science & technology 2020;9:20
Schultz R, Schuster F, Lehmann T, Schmidt J, Augsten R, Hammer M. Simplified approach to least-square fitting of fluorescence lifetime ophthalmoscopy (FLIO) data by fixating lifetimes. Biomed Opt Express 2019;10:5996-6008
Hasan SM, Hammer M, Meller D. Correlation of the Retinal Parapapillary Perfusion and the Retinal Vessel Oxygen Saturation in Glaucoma Patients. Invest Ophthalmol Vis Sci 2019;60:1309-1315
Schultz, R., Gamage, Kushmali C. L. K., Messinger, Jeffrey D., Curcio, Christine A., Hammer, M. Fluorescence Lifetimes and Spectra of RPE and Sub-RPE Deposits in Histology of Control and AMD Eyes, Investigative Ophthalmology & Visual Science 61 (2020) 11, p.9
Brauer, J.L., Schultz, R., Klemm, M., Hammer, M. Influence of lens fluorescence on fluorescence lifetime imaging ophthalmoscopy (FLIO) fundus imaging and strategies for its compensation, TVST 2020 Jul 9;9(8):13