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1.
Retina ; 44(7): 1232-1241, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38471039

ABSTRACT

PURPOSE: To evaluate the impact of optical coherence tomography phenotypes preceding atrophy related to age-related macular degeneration on the progression of atrophic lesions. METHODS: In this observational retrospective cohort study, a total of 70 eyes of 60 consecutive patients with intermediate age-related macular degeneration with a minimum follow-up of 24 months were included. The atrophy was quantified using fundus autofluorescence, also considering the directionality of atrophy as centrifugal and centripetal progression rates. The main outcome measures were geographic atrophy (GA) progression rate (mm 2 /year) and square root transformation of GA (mm 2 /year). RESULTS: The best-fit model for GA (odds ratio: 1.81, P < 0.001) and square root transformation of GA (odds ratio: 1.36, P < 0.001) areas revealed that the main baseline predictor was the presence of a retinal pigment epithelium-basal lamina-Bruch membrane splitting. Large drusen at baseline appeared protective for the GA area lesion expansion over time (odds ratio: 0.52, P < 0.001) when considered with other confounders. CONCLUSION: A thin retinal pigment epithelium-basal lamina-Bruch membrane splitting without evidence of neovascularization on optical coherence tomography angiography likely represents an optical coherence tomography signature for late basal laminar deposits. Identifying this phenotype can help identify individuals with a higher risk of rapid progression and atrophy expansion.


Subject(s)
Disease Progression , Fluorescein Angiography , Geographic Atrophy , Phenotype , Retinal Pigment Epithelium , Tomography, Optical Coherence , Humans , Tomography, Optical Coherence/methods , Geographic Atrophy/diagnosis , Retrospective Studies , Male , Female , Aged , Retinal Pigment Epithelium/pathology , Retinal Pigment Epithelium/diagnostic imaging , Fluorescein Angiography/methods , Aged, 80 and over , Follow-Up Studies , Visual Acuity , Fundus Oculi , Middle Aged , Bruch Membrane/pathology , Bruch Membrane/diagnostic imaging
2.
Clin Exp Ophthalmol ; 52(3): 317-333, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38348562

ABSTRACT

Gender medicine is a medical specialty that addresses gender differences in health and disease. Traditionally, medical research and clinical practice have often been focused on male subjects and patients. As a result, gender differences in medicine have been overlooked. Gender medicine considers the biological, psychological, and social differences between the genders and how these differences affect the development, diagnosis, treatment, and prevention of disease. For ophthalmological diseases epidemiological differences are known. However, there are not yet any gender-based ophthalmic treatment approaches for women and men. This review provides an overview of gender differences in retinal diseases. It is intended to make ophthalmologists, especially retinologists, more sensitive to the topic of gender medicine. The goal is to enhance comprehension of these aspects by highlighting fundamental gender differences. Integrating gender medicine into ophthalmological practice helps promote personalized and gender-responsive health care and makes medical research more accurate and relevant to the entire population.


Subject(s)
Biomedical Research , Ophthalmology , Retinal Diseases , Humans , Male , Female , Sex Factors , Delivery of Health Care , Retinal Diseases/diagnosis , Retinal Diseases/epidemiology , Retinal Diseases/therapy
3.
Clin Exp Ophthalmol ; 51(3): 217-228, 2023 04.
Article in English | MEDLINE | ID: mdl-36597823

ABSTRACT

Retinal vascular diseases represent a broad field of ocular pathologies. Retinal imaging is an important tool for diagnosis, prognosis and follow up of retinal vascular diseases. It includes a wide variety of imaging techniques ranging from colour fundus photography and optical coherence tomography to dynamic diagnostic options such as fluorescein angiography, and optical coherence tomography angiography. The newest developments in respective imaging techniques include widefield imaging to assess the retinal periphery, which is of especial interest in retinal vascular diseases. Automatic image analysis and artificial intelligence may support the image analysis and may prove valuable for prognostic purposes. This review provides a broad overview of the imaging techniques that have been used in the past, today and maybe in the future to stage and monitor retinal vascular disease with focus on the main disease entities including diabetic retinopathy, retinal vein occlusion, and retinal artery occlusion.


Subject(s)
Diabetic Retinopathy , Retinal Vein Occlusion , Humans , Artificial Intelligence , Fluorescein Angiography/methods , Diagnostic Techniques, Ophthalmological , Retinal Vein Occlusion/diagnosis , Retina , Tomography, Optical Coherence/methods , Diabetic Retinopathy/diagnosis
4.
Retina ; 42(12): 2388-2394, 2022 12 01.
Article in English | MEDLINE | ID: mdl-36394892

ABSTRACT

PURPOSE: To assess whether macular fluorescence lifetimes may serve as a predictor for long-term outcomes in macula-off rhegmatogenous retinal detachment. METHODS: A single-center observational study was conducted. Patients with pseudophakic macula-off rhegmatogenous retinal detachment were included and evaluated 1 and 6 months after successful reattachment surgery. Fluorescence lifetime imaging ophthalmoscopy lifetimes in the central Early Treatment Diabetic Retinopathy Study grid subfield, in two distinct channels (short spectral channel and long spectral channel) were analyzed. Best-corrected visual acuity optical coherence tomography of the macula and fluorescence lifetimes were measured at month 1 and month 6. RESULTS: Nineteen patients were analyzed. Lifetimes of the previously detached retinas were prolonged compared with the healthy fellow eyes. Short lifetimes at month 1 were associated with better best-corrected visual acuity improvement (short spectral channel: r2 = 0.27, P < 0.05, long spectral channel: r2 = 0.23, P < 0.05) and with good final best-corrected visual acuity (short spectral channel: r2 = 0.43, P < 0.01, long spectral channel: r2 = 0.25, P < 0.05). Lifetimes were prolonged in some cases of outer retinal damage in optical coherence tomography scans. CONCLUSION: Fluorescence lifetime imaging ophthalmoscopy might serve as a prediction tool for functional recovery in pseudophakic macula-off rhegmatogenous retinal detachment. Retinal fluorescence lifetimes could give insight in molecular processes after rhegmatogenous retinal detachment.


Subject(s)
Macula Lutea , Retinal Detachment , Humans , Retinal Detachment/diagnosis , Retinal Detachment/surgery , Visual Acuity , Ophthalmoscopy , Tomography, Optical Coherence/methods
5.
Retina ; 41(11): 2378-2390, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34111887

ABSTRACT

PURPOSE: To investigate and quantify the influence of imaging artifacts on retinal fluorescence lifetime (FLIO) values and to provide helpful hints and tricks to avoid imaging artifacts and to improve FLIO image acquisition quality. METHODS: A systematic analysis of potential parameters influencing FLIO quality and/or fluorescence lifetime values was performed in a prospective systematic experimental imaging study in five eyes of five healthy subjects. For image acquisition, a fluorescence lifetime imaging ophthalmoscope (Heidelberg Engineering) was used. Quantitative analysis of FLIO lifetime changes due to imaging artifacts was performed. RESULTS: Imaging artifacts with significant influence on fluorescence lifetimes included too short image acquisition time, insufficient illumination, ocular surface problems, and image defocus. Prior use of systemic or topical fluorescein makes analysis of retinal fluorescence lifetimes impossible. CONCLUSION: Awareness of possible sources of imaging artifacts is important for FLIO image acquisition and analysis. Therefore, standardized imaging and analysis procedure in FLIO is crucial for high-quality image acquisition and the possibility for systematic quantitative fluorescence lifetime analysis.


Subject(s)
Artifacts , Ophthalmoscopy/methods , Retina/diagnostic imaging , Retinal Diseases/diagnosis , Adult , Female , Fluorescein Angiography/methods , Fundus Oculi , Humans , Male , Middle Aged , Prospective Studies , Tomography, Optical Coherence/methods
6.
Retina ; 41(11): 2391-2398, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34282069

ABSTRACT

PURPOSE: Short foveal fluorescence lifetimes (fFLT) in geographic atrophy are typically found in eyes with foveal sparing (FS) but may also occur in eyes without FS. We investigated whether short fFLT could serve as a functional biomarker for disease progression in geographic atrophy. METHODS: Thirty three eyes were followed over the course of 4 to 6 years. Foveal sparing was assessed using fluorescence lifetime imaging ophthalmoscopy, optical coherence tomography, fundus Autofluorescence, and macular pigment optical density. RESULTS: Eyes with FS exhibited shorter fFLT compared with eyes without FS. Short fFLT (<600 ps) were measured in all eyes with FS and half of the eyes without FS. Eyes with FS showed a bigger increase in fFLT per year (+39/+30 ps (short spectral channel/long spectral channel) in FS versus +29/+22 ps (short spectral channel/long spectral channel) in non FS). The best-corrected distance visual acuity correlated significantly with fFLT (P = 0.018 and P = 0.005 for short spectral channel/long spectral channel). Macular pigment optical density measurements correlated significantly with fFLT but not in all spectral channels (P ranging from 0.018 to 0.077). CONCLUSION: In geographic atrophy, shorter fFLT are associated with FS but they can also be observed in eyes without FS. Our longitudinal data suggest that shorter fFLT features in eyes with loss of FS represent an earlier stage of disease and may be more prone to loss of the visual acuity.


Subject(s)
Fovea Centralis/diagnostic imaging , Geographic Atrophy/diagnosis , Ophthalmoscopy/methods , Retinal Pigment Epithelium/diagnostic imaging , Aged , Aged, 80 and over , Disease Progression , Female , Fluorescein Angiography/methods , Follow-Up Studies , Fundus Oculi , Humans , Male , Time Factors , Tomography, Optical Coherence/methods
7.
Klin Monbl Augenheilkd ; 238(9): 951-961, 2021 Sep.
Article in English, German | MEDLINE | ID: mdl-34492711

ABSTRACT

The choroid is directly adjacent to the retina and consists of a dense vascular network that supplies the outer retina. Pathologies in the choroid can lead to changes in the retinal pigment epithelium (RPE) and photoreceptors. Thus, the choroid plays a crucial role in the development of retinal diseases such as age-related macular degeneration (AMD), central serous chorioretinopathy (CSCR), pathologic myopia, and inflammatory diseases such as Vogt-Koyanagi-Harada syndrome (VKH). Basic knowledge of the structure and physiology of the choroid, as well as diagnostic options for visualizing choroidal changes, provides a better understanding of the physiology and pathology of choroidal processes. This review provides an overview of the anatomy and function of the choroid, and describes the diagnostic techniques currently available to characterize and visualize the choroid. It also includes an overview of various retinal conditions, which are associated with choroidal changes.


Subject(s)
Central Serous Chorioretinopathy , Uveomeningoencephalitic Syndrome , Central Serous Chorioretinopathy/diagnostic imaging , Choroid/diagnostic imaging , Fluorescein Angiography , Humans , Retinal Pigment Epithelium/diagnostic imaging , Tomography, Optical Coherence
8.
Retina ; 40(12): 2332-2342, 2020 Dec.
Article in English | MEDLINE | ID: mdl-31876892

ABSTRACT

PURPOSE: To systematically and longitudinally investigate the characteristics of flecks in ABCA4-related retinopathy under different fundus autofluorescence (AF) excitation and emission spectra. METHODS: A total of 132 eyes of 66 patients with ABCA4-related retinopathy were investigated using multimodal AF imaging and spectral domain optical coherence tomography. Autofluorescence imaging with blue (BAF), green (GAF), and near-infrared (NIR-AF) excitation wavelengths obtained by a confocal scanning laser ophthalmoscope was compared with AF imaging obtained by an innovative confocal light-emitting diode-based retinal imaging system (Color-AF) that allows for separation of short (green emission fluorescent component) and long (red emission fluorescent component) autofluorescence emission components. RESULTS: Color-AF, BAF, and GAF, overall, revealed similar presentation of hyperautofluorescent flecks. Flecks that showed predominantly red emission fluorescent component matched with hyperautofluorescent flecks in NIR-AF. Over the observation time of 5 to 14 months, flecks showed a transition in the AF emission spectrum to shorter wavelengths (red emission fluorescent component to green emission fluorescent component), associated with a progressed disruption of overlaying outer retinal bands in optical coherence tomography. Newer hyperautofluorescent flecks usually revealed predominantly red emission fluorescent component. CONCLUSION: By separation of the AF spectra, the remodeling of fluorophores and associated structural changes can be monitored over time indicating a novel and susceptible surrogate marker for disease progression and potential therapeutic effects.


Subject(s)
ATP-Binding Cassette Transporters/genetics , Lipofuscin/metabolism , Optical Imaging , Retinal Dystrophies/diagnostic imaging , Retinal Dystrophies/metabolism , Adolescent , Adult , Aged , Aged, 80 and over , Child , Cross-Sectional Studies , Female , Fluorescein Angiography , Follow-Up Studies , Fundus Oculi , Humans , Male , Middle Aged , Multimodal Imaging , Ophthalmoscopy , Retinal Dystrophies/genetics , Tomography, Optical Coherence , Visual Acuity/physiology
9.
Retina ; 40(1): 99-108, 2020 Jan.
Article in English | MEDLINE | ID: mdl-30664123

ABSTRACT

PURPOSE: Type 2 idiopathic macular telangiectasia (MacTel) is a rare bilateral neurodegenerative disease characterized by alterations in the macular capillary network leading to central vision loss. The purpose of this study was to quantify disease-specific retinal fluorescence lifetime patterns in patients with MacTel using fluorescence lifetime imaging ophthalmoscopy. PARTICIPANTS: Both eyes of 14 patients (mean age ± SEM, 67.8 ± 6.4 years) with a clinical diagnosis of MacTel Type 2 and 14 healthy age-matched controls (age 69.8 ± 6.4 years) were included in this study. METHODS: All participants were imaged with a fluorescence lifetime imaging ophthalmoscope (Heidelberg Engineering, Germany). Mean retinal fluorescence lifetimes (Tm) were obtained in the short spectral channels (498-560 nm) and long spectral channels (560-720 nm). Clinical features, fundus images, fundus autofluorescence intensity images, spectral domain optical coherence tomography, and corresponding macular pigment optical density measurements using a modified confocal scanning laser ophthalmoscope (mpHRA) were further analyzed. Patients were classified into five phenotypic subgroups using the Gass and Blodi classification. RESULTS: Mean fluorescence lifetimes were significantly prolonged temporal to the fovea in patients with MacTel compared with healthy controls (mean ± SEM: short spectral channels 543 ± 61 ps vs. 304 ± 9 ps; P < 0.0001; long spectral channels: 447 ± 26 ps vs. 348 ± 11 ps; P < 0.0001), and appeared as a crescent or ring-shaped pattern. Prolonged lifetime patterns correlated with decreased macular pigment density on macular pigment optical density measurements. Follow-up examinations were performed in four MacTel patients, which revealed an increase of short spectral channel Tm of 22% over 2.1 years in the temporal fovea. CONCLUSION: This study confirms that fundus autofluorescence lifetimes display characteristic patterns in patients with MacTel Type 2 disease and provide information about macular pigment and possibly photoreceptor loss. Fluorescence lifetime prolongation correlates with disease severity and may therefore be a useful addition to other imaging modalities for assessing disease progression in MacTel Type 2.


Subject(s)
Fluorescence , Retina/diagnostic imaging , Retinal Telangiectasis/diagnostic imaging , Aged , Cross-Sectional Studies , Female , Fluorescein Angiography , Humans , Macular Pigment/metabolism , Male , Middle Aged , Ophthalmoscopy , Prospective Studies , Retina/physiopathology , Retinal Telangiectasis/metabolism , Retinal Telangiectasis/physiopathology , Tomography, Optical Coherence , Visual Acuity/physiology
10.
Retina ; 40(10): 1929-1937, 2020 Oct.
Article in English | MEDLINE | ID: mdl-31860523

ABSTRACT

PURPOSE: The purpose of this study was to investigate fluorescence lifetime imaging ophthalmoscopy lifetimes after macula-off rhegmatogenous retinal detachment (RRD) repair. METHODS: Fifty-eight patients with successful macula-off RRD reattachment surgery were included. Retinal autofluorescence was excited with 470 nm, and amplitude-weighted mean fluorescence lifetimes (Tm) were measured in a short spectral channel (SSC, 498-560 nm) and a long spectral channel (LSC, 560-720 nm). Tm were obtained within a standardized Early Treatment Diabetic Retinopathy Study grid and correlated with Tm. The unaffected fellow eye served as control. RESULTS: Fifty-eight patients (age: 65 ± 1.6 years, 11 women) were imaged at median 1.5 months postoperatively. Tm were significantly prolongxxxed within areas of previously detached retina in the long spectral channel and particularly in the central subfield in the short spectral channel. Short lifetimes in the center of the Early Treatment Diabetic Retinopathy Study grid correlated with better visual acuity (short spectral channel; r = 0.18, P = 0.001, long spectral channel; r = 0.08, P = 0.03). Areas of residual subretinal fluid pockets in four RRD eyes displayed short fluorescence lifetimes. CONCLUSION: Areas of previously detached retina exhibit significant fluorescence lifetime changes. We found a significant correlation of fluorescence lifetimes within the fovea with visual acuity after successful RRD repair. Our data suggests that the prolongation of fluorescence lifetimes in the fovea is mainly driven by loss of macular pigment. Therefore, fluorescence lifetime imaging ophthalmoscopy may be useful in the prediction of long-term functional outcomes after macula-off RRD surgery.


Subject(s)
Endotamponade , Optical Imaging , Retinal Detachment/diagnostic imaging , Retinal Detachment/surgery , Vitrectomy , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Ophthalmoscopy , Retinal Detachment/physiopathology , Tomography, Optical Coherence , Visual Acuity/physiology
11.
Ophthalmologica ; 243(3): 195-206, 2020.
Article in English | MEDLINE | ID: mdl-31743906

ABSTRACT

PURPOSE: To investigate whether autofluorescence lifetime patterns within retinal pigment epithelium (RPE) atrophy differ between age-related macular degeneration (AMD) and Stargardt disease (STGD). METHODS: Mean retinal autofluorescence lifetimes were measured in a short and a long spectral channel (SSC: 498-560 nm; LSC: 560-720 nm). Mean retinal fluorescence lifetimes were analyzed with corresponding clinical features, fundus images, fundus autofluorescence intensity images, and optical coherence tomography. Mean fluorescence lifetime values of atrophic areas were compared between the two cohorts and within the same patient to adjacent nonatrophic regions. RESULTS: Mean fluorescence lifetimes within areas with RPE atrophy of 13 patients with STGD (mean age ± SEM 43.7 ± 5 years) and 30 patients with geographic atrophy (mean age: 78 ± 2 years) were analyzed and compared to age-matched healthy participants. The mean area of RPE atrophy in STGD and AMD was 6.6 ± 2.3 mm2 (range: 0.66-33.17 mm2) and 17.5 ± 3.8 mm2 (range: 0.58-50.02 mm2), respectively. In patients with AMD, atrophic areas revealed significantly longer mean fluorescence lifetime values as compared with patients with STGD (SSC: 997 ± 60 vs. 363 ± 26 ps; LSC: 880 ± 46 vs. 393 ± 23 ps; p < 0.0001). CONCLUSIONS: This study established that RPE atrophy in patients secondary to STGD and AMD display distinctive mean fluorescence lifetime characteristics. As retinal fluorescence lifetimes within areas of RPE atrophy were significantly longer in AMD patients, the analysis of specific lifetime patterns may provide additional insight into the disease processes and the pathogenetic mechanisms in the development of atrophic patches in AMD and STGD.


Subject(s)
Macular Degeneration/complications , Optical Imaging , Retinal Diseases/etiology , Retinal Pigment Epithelium/pathology , Stargardt Disease/complications , Adult , Aged , Aged, 80 and over , Atrophy , Female , Humans , Macular Degeneration/diagnosis , Male , Middle Aged , Ophthalmoscopy , Prospective Studies , Retinal Diseases/diagnosis , Stargardt Disease/diagnosis , Tomography, Optical Coherence , Visual Acuity , Young Adult
12.
Retina ; 39(5): 879-888, 2019 May.
Article in English | MEDLINE | ID: mdl-30985551

ABSTRACT

PURPOSE: Stargardt disease is the most common inherited juvenile macular dystrophy and is characterized by yellowish flecks across the posterior pole. The purpose of this study was to investigate fluorescence lifetime changes of retinal flecks over time using fluorescence lifetime imaging ophthalmoscopy. METHODS: Longitudinal fluorescence lifetime data of 12 patients with Stargardt disease (mean age ± SEM, 42.25 ± 2.1 years; range, 28-58 years) were acquired using a fluorescence lifetime imaging ophthalmoscope based on a Heidelberg Engineering Spectralis system. Retinal autofluorescence was excited with a 470-nm laser. The emitted fluorescence was detected in two wavelength channels: a short spectral channel (498-560 nm) and a long spectral channel (560-720 nm). The mean retinal autofluorescence lifetimes were calculated and further analyzed with corresponding color fundus images, autofluorescence intensity images, and spectral domain optical coherence tomography. Patients were classified into three subtypes. RESULTS: All patients with Stargardt disease displayed characteristic autofluorescence lifetime patterns. Mean fluorescence lifetime values within areas of yellow flecks were significantly prolonged (long spectral channel 484 ps) compared with the surrounding tissue (long spectral channel 297 ps). In 91.6% of the eyes, flecks with short fluorescence lifetimes (long spectral channel 255 ps) were identified. Short lifetime flecks progressed to flecks with characteristic long lifetimes in 75.1% of eyes within a mean interval of 29.2 months (range 3-45 months). Between baseline and follow-up, the rate of newly developed short lifetime flecks (number/per year) based on subtypes was 2.62 in Group 1, 1.43 in Group 2, and 0.81 in Group 3. CONCLUSION: Recent onset flecks in Stargardt disease display short fluorescence lifetimes and convert into longer fluorescence lifetime flecks over time. This transition may represent a change in the composition of retinal deposits with accumulation of lipofuscin and retinoid by-products from the visual cycle. With emerging treatment options, these findings may prove useful to monitor disease progression and therapeutic effects.


Subject(s)
Fluorescein Angiography/methods , Ophthalmoscopy/methods , Retina/pathology , Stargardt Disease/diagnosis , Tomography, Optical Coherence/methods , Visual Acuity , Adult , Disease Progression , Female , Follow-Up Studies , Fundus Oculi , Humans , Male , Middle Aged , Time Factors
13.
Retina ; 37(11): 2151-2161, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28099314

ABSTRACT

PURPOSE: To quantify retinal fluorescence lifetimes in patients with central serous chorioretinopathy (CSC) and to identify disease specific lifetime characteristics over the course of disease. METHODS: Forty-seven participants were included in this study. Patients with central serous chorioretinopathy were imaged with fundus photography, fundus autofluorescence, optical coherence tomography, and fluorescence lifetime imaging ophthalmoscopy (FLIO) and compared with age-matched controls. Retinal autofluorescence was excited using a 473-nm blue laser light and emitted fluorescence light was detected in 2 distinct wavelengths channels (498-560 nm and 560-720 nm). Clinical features, mean retinal autofluorescence lifetimes, autofluorescence intensity, and corresponding optical coherence tomography (OCT) images were further analyzed. RESULTS: Thirty-five central serous chorioretinopathy patients with a mean visual acuity of 78 ETDRS letters (range, 50-90; mean Snellen equivalent: 20/32) and 12 age-matched controls were included. In the acute stage of central serous chorioretinopathy, retinal fluorescence lifetimes were shortened by 15% and 17% in the respective wavelength channels. Multiple linear regression analysis showed that fluorescence lifetimes were significantly influenced by the disease duration (P < 0.001) and accumulation of photoreceptor outer segments (P = 0.03) but independent of the presence or absence of subretinal fluid. Prolonged central macular autofluorescence lifetimes, particularly in eyes with retinal pigment epithelial atrophy, were associated with poor visual acuity. CONCLUSION: This study establishes that autofluorescence lifetime changes occurring in central serous chorioretinopathy exhibit explicit patterns which can be used to estimate perturbations of the outer retinal layers with a high degree of statistical significance.


Subject(s)
Central Serous Chorioretinopathy/diagnosis , Choroid/pathology , Fluorescein Angiography/methods , Ophthalmoscopy/methods , Retinal Pigment Epithelium/pathology , Tomography, Optical Coherence/methods , Acute Disease , Adult , Cells, Cultured , Female , Follow-Up Studies , Fundus Oculi , Humans , Male , Middle Aged , Time Factors , Visual Acuity
14.
Exp Eye Res ; 153: 178-185, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27777124

ABSTRACT

Fluorescence lifetime imaging ophthalmoscopy (FLIO) was used to investigate retinal autofluorescence lifetimes in mouse models of pharmacologically induced retinal degeneration over time. Sodium iodate (NaIO3, 35 mg/kg intravenously) was used to induce retinal pigment epithelium (RPE) degeneration with subsequent loss of photoreceptors (PR) whereas N-methyl-N-nitrosourea (MNU, 45 mg/kg intraperitoneally) was employed for degeneration of the photoreceptor cell layer alone. All mice were measured at day 3, 7, 14, and 28 after the respective injection of NaIO3, MNU or NaCl (control). Fluorescence lifetime imaging was performed using a fluorescence lifetime imaging ophthalmoscope (Heidelberg Engineering, Heidelberg, Germany). Fluorescence was excited at 473 nm and fluorescence lifetimes were measured in a short and a long spectral channel (498-560 nm and 560-720 nm). Corresponding optical coherence tomography (OCT) images were consecutively acquired and histology was performed at the end of the experiments. Segmentation of OCT images and histology verified the cell type-specific degeneration process over time. Retinal autofluorescence lifetimes increased from day 3 to day 28 in mice after NaIO3 treatment. Finally, at day 28, fluorescence lifetimes were prolonged by 8% in the short and 61% in the long spectral channel compared to control animals (p = 0.21 and p = 0.004, respectively). In mice after MNU treatment, the mean retinal autofluorescence lifetimes were already decreased at day 3 and retinal lifetimes were finally shortened by 27% in the short and 51% in the long spectral channel at day 28 (p = 0.0028). In conclusion, degeneration of the RPE with subsequent photoreceptor degeneration by NaIO3 lead to longer mean fluorescence lifetimes of the retina compared to control mice, whereas during specific degeneration of the photoreceptor layer induced by MNU shorter lifetimes were measured. Therefore, short retinal fluorescence lifetimes may originate from the RPE and may be modified by the overlaying retinal layers.


Subject(s)
Fluorescein Angiography/methods , Retinal Degeneration/pathology , Retinal Pigment Epithelium/pathology , Animals , Disease Models, Animal , Fundus Oculi , Iodates/toxicity , Mice , Ophthalmoscopy/methods , Retinal Degeneration/chemically induced , Retinal Pigment Epithelium/drug effects , Tomography, Optical Coherence/methods
15.
PLoS One ; 18(1): e0279158, 2023.
Article in English | MEDLINE | ID: mdl-36608033

ABSTRACT

PURPOSE: To investigate the influence of the lens status and to describe fundus autofluorescence lifetimes (FLT) in a large cohort of healthy eyes across a wide age range. MATERIALS AND METHODS: FLT data were acquired from healthy phakic and pseudophakic eyes using fluorescence lifetime imaging ophthalmoscopy (FLIO). Retinal autofluorescence was excited with a 473 nm laser and emitted autofluorescence was detected in a short and a long spectral channel (SSC: 498-560 nm; LSC: 560-720 nm). RESULTS: 141 healthy eyes from 141 participants (56 ± 18 years) were included. The shortest mean FLTs were measured within the macular center, followed by the temporal inner and outer ETDRS (Early Treatment Diabetic Retinopathy Study) grid segments, and the remaining areas of the inner and the outer ETDRS ring. In phakic participants (81%), mean, short and long FLTs correlated with the age (SSC: r2 = 0.54; LSC: r2 = 0.7; both p<0.0001) with an increase of about 33 ps in the SSC resp. 28 ps in the LSC per decade. In pseudophakic subjects (19%), mean FLTs only correlated with age in the long spectral channel (r2 = 0.44; p = 0.0002) but not in the short spectral channel (r2 = 0.066; p = 0.2). CONCLUSIONS: Fundus autofluorescence lifetimes are age dependent. FLTs in the SSC are more susceptible to lens opacities but less dependent on age changes, whereas FLTs in the LSC are largely independent of the lens status but display a higher degree of age dependency. STUDY REGISTRY: ClinicalTrials.gov NCT01981148.


Subject(s)
Optical Imaging , Retina , Humans , Fluorescein Angiography/methods , Fundus Oculi , Ophthalmoscopy/methods , Tomography, Optical Coherence/methods
16.
Clin Nutr ESPEN ; 56: 127-134, 2023 08.
Article in English | MEDLINE | ID: mdl-37344061

ABSTRACT

BACKGROUND & AIMS: Oral lutein (L) and zeaxanthin (Z) supplementation enhances macular pigment optical density (MPOD) and plays a protective role in the development of age-related macular degeneration (AMD). Fluorescence lifetime imaging ophthalmoscopy (FLIO) is a novel in vivo retinal imaging method that has been shown to correlate to classical MPOD measurements and might contribute to a metabolic mapping of the retina in the future. Our aim was to show that oral supplementation of L and Z affects the FLIO signal in a positive way in patients with AMD. METHODS: This was a prospective, single center, open label cohort study. Patients with early and intermediate AMD received oral L and Z supplementation during three months, and were observed for another three months after therapy termination. All visits included measurements of clinical parameters, serum L and Z concentration, MPOD measurements using heterochromatic flicker photometry, dual wavelength autofluorescence imaging, and FLIO. Correlation analysis between FLIO and MPOD were performed. RESULTS: Twenty-one patients completed the follow up period. Serum L and Z concentrations significantly increased during supplementation (mean difference 244.8 ng/ml; 95% CI: 81.26-419.9, and 77.1 ng/ml; 95% CI: 5.3-52.0, respectively). Mean MPOD units significantly increased (mean difference 0.06; 95% CI: 0.02-0.09; at 0.5°, 202; 95% CI: 58-345; at 2°, 1033; 95% CI: 288-1668; at 9° of eccentricity, respectively) after three months of supplementation with macular xanthophylls, which included L and Z. Median FLIO lifetimes in the foveal center significantly decreased from 277.3 ps (interquartile range 230.2-339.1) to 261.0 ps (interquartile range 231.4-334.4, p = 0.027). All parameters returned to near-normal values after termination of the nutritional supplementation. A significant negative correlation was found between FLIO and MPOD (r2 = 0.57, p < 0.0001). CONCLUSIONS: FLIO is able to detect subtle changes in MPOD after L and Z supplementation in patients with early and intermediate AMD. Our findings confirm the previous described negative correlation between FLIO and MPOD. Macular xanthophylls seem to contribute to short foveal lifetimes. This study is registered at ClinicalTrials.gov (identifier number NCT04761341).


Subject(s)
Macular Degeneration , Macular Pigment , Humans , Lutein , Macular Pigment/metabolism , Zeaxanthins , Pilot Projects , Prospective Studies , Cohort Studies , Macular Degeneration/drug therapy , Dietary Supplements , Ophthalmoscopy
17.
Sci Rep ; 12(1): 14337, 2022 08 29.
Article in English | MEDLINE | ID: mdl-36038591

ABSTRACT

Clinical discrimination of posterior uveitis entities remains a challenge. This exploratory, cross-sectional study investigated the green (GEFC) and red emission fluorescent components (REFC) of retinal and choroidal lesions in posterior uveitis to facilitate discrimination of the different entities. Eyes were imaged by color fundus photography, spectrally resolved fundus autofluorescence (Color-FAF) and optical coherence tomography. Retinal/choroidal lesions' intensities of GEFC (500-560 nm) and REFC (560-700 nm) were determined, and intensity-normalized Color-FAF images were compared for birdshot chorioretinopathy, ocular sarcoidosis, acute posterior multifocal placoid pigment epitheliopathy (APMPPE), and punctate inner choroidopathy (PIC). Multivariable regression analyses were performed to reveal possible confounders. 76 eyes of 45 patients were included with a total of 845 lesions. Mean GEFC/REFC ratios were 0.82 ± 0.10, 0.92 ± 0.11, 0.86 ± 0.10, and 1.09 ± 0.19 for birdshot chorioretinopathy, sarcoidosis, APMPPE, and PIC lesions, respectively, and were significantly different in repeated measures ANOVA (p < 0.0001). Non-pigmented retinal/choroidal lesions, macular neovascularizations, and fundus areas of choroidal thinning featured predominantly GEFC, and pigmented retinal lesions predominantly REFC. Color-FAF imaging revealed involvement of both, short- and long-wavelength emission fluorophores in posterior uveitis. The GEFC/REFC ratio of retinal and choroidal lesions was significantly different between distinct subgroups. Hence, this novel imaging biomarker could aid diagnosis and differentiation of posterior uveitis entities.


Subject(s)
Sarcoidosis , Uveitis, Posterior , Birdshot Chorioretinopathy , Coloring Agents , Cross-Sectional Studies , Fluorescein Angiography/methods , Humans , Optical Imaging/methods , Tomography, Optical Coherence/methods , Uveitis, Posterior/diagnostic imaging
18.
Transl Vis Sci Technol ; 10(4): 33, 2021 04 01.
Article in English | MEDLINE | ID: mdl-34004011

ABSTRACT

Purpose: To investigate the influence of lens opacifications on fluorescence lifetime imaging ophthalmoscopy (FLIO). Methods: Forty-seven eyes of 45 patients were included. Mean fluorescence lifetimes (Tm) were recorded with a fluorescence lifetime imaging ophthalmoscope in a short spectral channel (SSC) and a long spectral channel (LSC). Retinal and lens autofluorescence lifetimes were measured in subjects before and after cataract surgery. Lens opacification was graded using the Lens Opacities Classification System III (LOCS III) classification. Results: The retinal Tm decreased significantly after cataract surgery in both spectral channels (SSC: -53%, P < 0.0001; LSC: -26%, P = 0.0041). The lens Tm differed significantly between the crystalline and the artificial lens in both spectral channels (P < 0.0001). The "nuclear opacity" and "nuclear color" score of the LOCS III classification correlated significantly with the mean Tm difference in both spectral channels (P < 0.0001). Conclusions: Lens opacification results in significantly longer retinal Tm. Therefore the lens status has to be considered when performing cross-sectional fluorescence lifetime analysis. Cataract-formation and cataract-surgery needs to be considered when conducting longitudinal studies. Grading of nuclear opacity following the LOCS III classification provides an approximate conversion formula for the mean change of lifetimes, which can be helpful in the interpretation of data in patients with lens opacities. Translational Relevance: FLIO is significantly influenced by lens opacities. Using a lens opacity grading scheme and measuring fluorescence lifetimes before and after cataract surgery, an approximative conversion formula can be calculated, which enables the comparison of lifetimes after cataract surgery or over the course of time.


Subject(s)
Cataract , Retina , Cataract/diagnostic imaging , Cross-Sectional Studies , Humans , Ophthalmoscopy , Optical Imaging , Retina/diagnostic imaging
19.
Ophthalmol Ther ; 9(1): 191-203, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32034689

ABSTRACT

Intravitreal injections with vascular endothelial growth factor inhibitors constitute the most prevalent ophthalmic procedure in developed countries. Historically, there has been steady growth in the number of treatments performed of this kind, and projection studies estimate further growth in such treatments in the future. We provide a practical approach to intravitreal injections and discuss important aspects relating to the setting, the patient, the procedure, and the information given to the patient.

20.
Ophthalmol Retina ; 4(3): 238-248, 2020 03.
Article in English | MEDLINE | ID: mdl-31753808

ABSTRACT

PURPOSE: To investigate the association between the presence of type 1 choroidal neovascularization (CNV) and the localized progression of atrophy in age-related macular degeneration (AMD). DESIGN: Analysis of patients' data collected in the context of 2 noninterventional, prospective studies conducted at the Department of Ophthalmology, University of Bonn, Germany. PARTICIPANTS: A total of 98 eyes diagnosed with AMD of 59 patients (40 female, 19 male) with a mean (±standard deviation) age at baseline of 76.60±6.65 years and median (interquartile range) review period of 1.17 years (1.01-1.55) were included. Eyes were subdivided into 3 categories based on multimodal imaging and ocular history: retinal pigment epithelium (RPE) atrophy with treatment-naïve quiescent CNV (n=7), RPE atrophy with a history of exudative CNV (n=10), and RPE atrophy without evidence of coexisting CNV (n=81). METHODS: Retinal pigment epithelium atrophy was delineated on the basis of serial fundus-autofluorescence and infrared-reflectance images. If CNV was detected by OCT angiography (OCTA), its location and dimension were spatially mapped to RPE atrophy. The localized progression of RPE atrophy in topographic relation to the CNV lesion was then analyzed using mixed-effects logistic regression. The spatial overlap (Dice coefficient) between predicted and observed RPE atrophy progression was evaluated to estimate the model accuracy. MAIN OUTCOME MEASURES: Odds ratio (OR) for localized RPE atrophy progression in areas overlying type 1 CNV. RESULTS: The prediction model achieved a high overlap between predicted and observed RPE atrophy progression with a cross-validated Dice coefficient of 0.87 (95% confidence interval [CI], 0.85-0.89) reflecting a high accuracy. The odds for future RPE atrophy involvement were reduced by a factor of 0.21 (95% CI, 0.19-0.24) in the presence of treatment-naïve quiescent type 1 CNV and by a factor of 0.46 (95% CI, 0.41-0.51) in the presence of exudative type 1 CNV. CONCLUSIONS: The results indicate that there is markedly reduced RPE atrophy progression in areas co-localizing with quiescent and exudative type 1 CNV. This observation is compatible with a potential protective effect of type 1 CNV on the RPE and overlying neurosensory retina. These results may have relevant clinical implications for the management of CNV and lead to new therapeutic strategies to prevent atrophy progression.


Subject(s)
Choroid/pathology , Choroidal Neovascularization/diagnosis , Fluorescein Angiography/methods , Macular Degeneration/complications , Retinal Pigment Epithelium/pathology , Tomography, Optical Coherence/methods , Aged , Choroidal Neovascularization/etiology , Disease Progression , Female , Follow-Up Studies , Fundus Oculi , Humans , Macular Degeneration/diagnosis , Male , Prospective Studies
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