[Hazards posed by LEDs? : A comparative study]. / Gefahr durch LED-Licht? : Eine vergleichende Untersuchung.

BACKGROUND: The increasing use of light-emitting diodes (LEDs) for lighting applications and displays is giving rise to public and professional concern that blue LED emissions could damage the retina or via the proven influence on the melatonin levels disrupt the human day-night rhythm. OBJECTIVE: The study aimed to measure the emission of LEDs and other relevant light sources and evaluate the results comparatively with the help of suitable evaluation functions in order to recognize whether LEDs differ considerably from other light sources in their hazard potential. MATERIAL AND METHODS: The spectra of a cold white and a warm white LED, a white tablet LED display, a fluorescent tube and a halogen lamp were measured and evaluated together with a sunlight spectrum relative to each other using the blue light hazard retina weighting function and the circadian action function. RESULT: Since LEDs can be very different, relative LED ratings also vary greatly. The warm white LED is the one with the lowest risk of blue light retinal damage and the lowest potential for inhibition of melatonin formation and in this respect even gentler than halogen lamps. For cold white LEDs, the values for photochemical retinal danger as well as for the expected inhibition of melatonin formation are much greater. The values for the tablet LED display are even higher. CONCLUSION: Not only LEDs but all examined light sources emit in the blue spectral range, so that in principle they represent a retinal hazard. Depending on the employed LED type, this hazard may be greater or less compared to conventional light sources but even cold white LEDs are rated slightly better than sunlight at noon. To support consumers it might be helpful to classify LEDs and other illuminants by their potential hazard to the eye, as they are already labelled with respect to their energy efficiency.

The efficacy and safety outcomes of the 0.19 mg fluocinolone acetonide implant after prior treatment with the 0.7 mg dexamethasone implant in patients with diabetic macular edema.

PURPOSE: There are little or no published data comparing the outcomes of ILUVIEN® (0.19 mg fluocinolone acetonide [FAc]) and OZURDEX® (0.7 mg dexamethasone [DEX]) implants in patients with diabetic macular edema (DME), and this case sought to compare their outcomes. METHODS: This case was extracted from a monocentric audit involving a pool of 25 patients (33 eyes) with DME and treated with a single FAc implant between October 2013 and December 2016. This case, a 61-year-old male with a pseudophakic lens, is from a patient that had received 4 intravitreal injections of a DEX implant prior to FAc implant and then was monitored for 3 years until re-treatment with a second FAc implant. Parameters measured included visual acuity (VA), central retinal thickness (CRT), and intraocular pressure (IOP). RESULTS: After the DEX implants, CRT transiently improved. In March 2014, the decision was taken to administer an FAc implant, and this led to a reduction in CRT below 300 µm (from a baseline of 748 µm), and this was sustained for 30 months. VA remained above 65 Early Treatment Diabetic Retinopathy Study letters to month 36, after which time a second FAc implant (in April 2017) was administered due to recurrence of edema and CRT decreased to below 300 µm and VA improved to 70 letters. Side effects included elevated IOP, which was effectively managed with IOP-lowering drops. CONCLUSION: A single injection of FAc implant led to sustained improvements in CRT and VA that lasted for between 30 and 36 months, which is in contrast to the DEX implant where re-treatment was generally required within 6-7 months. After 36 months, re-treatment with the FAc implant again led to improved VA and CRT, and responses that were similar to those achieved with the first FAc implant.

[Ophthalmic diaphanoscopy]. / Diaphanoskopie am Auge.

Diaphanoscopy is an almost 150-year-old diagnostic procedure based on the transillumination of the wall of the eyeball. One of the most important fields of application is the detection of tumors, which can be distinguished from the rest of the tissue by their reduced light transmission. Other fields of application include the diagnosis of retinal tears and holes, the detection of foreign bodies in the vitreous body and the control of coagulative measures in the ciliary body. In comparison to other techniques, diaphanoscopy requires only little effort and is very gentle on patients.

[Correlation from Undiluted Vitreous Cytokines of Untreated Central Retinal Vein Occlusion with Spectral Domain Optical Coherence Tomography]. / Korrelation von intravitrealen Zytokinen und OCT-Parametern bei Zentralvenenverschluss.

PURPOSE: To correlate key inflammatory and pro-angiogenic cytokines from undiluted vitreous fluid of treatment-naïve patients with central retinal vein occlusion (CRVO) with SD-OCT parameters. METHODS: Thirty-five patients (age 71.1 years, 24 phakic, 30 non-ischaemic) underwent intravitreal combination therapy, including single-site 23-gauge core vitrectomy. Twenty-eight samples from patients with idiopathic, non-uveitis floaterectomy served as controls. Levels of interleukin 6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and vascular endothelial growth factor (VEGF-A) were correlated with visual acuity (logMar), category of CRVO (ischaemic or non-ischaemic) and morphological parameters, such as central macular thickness (CMT), thickness of neurosensory retina (Tneuro), extent of serous retinal detachment (SRT) and disintegrity of the IS/OS and others. RESULTS: Mean IL-6 was 64.7 pg/ml (SD ± 115.8), mean MCP-1 1015.7 pg/ml (± 970.1), and mean VEGF-A 278.4 pg/ml (± 512.8), which was significantly higher than the control values of IL-6 6.2 ± 3.4 pg/ml (p = 0.06), MCP-1 253.2 ± 73.5 pg/ml (p < 0.0 000 001) and VEGF-A 7.0 ± 4.9 pg/ml (p < 0.0006), respectively. All cytokines correlated highly with one another (correlation coefficient r = 0.82 for IL-6 and MCP-1; r = 0.68 for Il-6 and VEGF-A; r = 0.64 for MCP-1 and VEGF-A). IL-6 correlated significantly with CMT, TRT, SRT, dIS/OS, and dELM. MCP-1 correlated significantly with SRT, dIS/OS, and dELM. VEGF-A did not correlate with changes in SD-OCT, while it had a trend to be higher in the ischaemic versus the non-ischaemic CRVO groups (p = 0.09). CONCLUSIONS: The inflammatory cytokines were more often correlated with morphological changes assessed by SD-OCT, whereas VEGF-A did not correlate with CRVO-associated changes in SD-OCT. VEGF inhibition alone may not be sufficient to decrease the inflammatory response in CRVO therapy.

[Half-Dose Verteporfin Photodynamic Therapy (hdPDT) in the Treatment of Central Serous Chorioretinopathy]. / Photodynamische Therapie mit halber Verteporfin-Dosis zur Behandlung der Chorioretinopathia Centralis Serosa.

BACKGROUND: To estimate the efficacy and safety profile of half-dose photodynamic therapy (hdPDT) for treating central serous chorioretinopathy (CSC). PATIENTS AND METHODS: An interventional, retrospective case series of patients with CSC (symptoms ≧ 3 months) receiving half-dose PDT (3 mg/m2 verteporfin). The ophthalmic examination at baseline and at 8 and 16 weeks after treatment included slit-lamp biomicroscopy, indirect ophthalmoscopy, measurement of intraocular pressure (IOP), ETDRS best-corrected visual acuity (BCVA), Amsler grid screening and contrast visual acuity (CVA). Fluorescein angiography (FA), autofluorescence (FAF) and optical coherence tomography (OCT) were measured at each visit. Central macular thickness (CMT) was measured automatically. RESULTS: 12 eyes of 12 patients (10 male and 2 female patients; mean age 46.6 ± 7.91 years) were included in this study. Anatomical resolution was obtained in 10 eyes (83.4 %) at week 16, but 2 eyes (16.6 %) exhibited persistent SRD throughout the follow-up period. Baseline CMT decreased from initially 330.1 µm ± 131.3 to 205.6 µm ± 97.6 (p = 0.034) at week 8 and to 220.3 µm ± 120.1 (p = 0.05) at week 16. Visual acuity (number of total letters read) significantly improved from initially 82.8 ± 11.5 to 86.8 ± 13.9 at week 8 and 91.3 ± 13.8 at week 16 (p = 0.012). Contrast visual acuity (calculated decimal visual acuity) significantly improved from initially 0.14 ± 0.09 to 0.38 ± 0.28 (p = 0.002) at week 16. After therapy, no significant changes in RPE could be detected with FAF and no ocular adverse events were observed. CONCLUSION: PDT with half-dose verteporfin resulted in reduced leakage in FA, enhanced visual acuity and resolution of subretinal fluid in OCT in patients with CSC, with no detected side effects of treatment.

[Fiberless miniature chandelier LED endoilluminator for pars plana vitrectomy]. / Faserloser Miniatur-Chandelier-LED-Endoilluminator für die Pars-plana-Vitrektomie.

BACKGROUND: Currently available chandelier endoilluminators for pars plana vitrectomy consist of conventional optical fibers coupled to a light source. The light probes of these fibers now provide wide emittance angles but it is still often not possible to illuminate the whole intraocular space via just one incision. Therefore, several light probes or additional handheld endoilluminators have to be used simultaneously or the lights have to be repositioned during surgery. OBJECTIVE: The presented prototype of a fiberless chandelier light-emitting diode (LED) endoilluminator aims at illuminating the whole intraocular space with just one incision while reducing the risk of harming the retina. MATERIAL AND METHODS: The light source is a white LED with a conical tip that allows stable fixation within an incision. The physical properties of these LEDs were determined and used for calculating the relevant irradiance to assess the risk of causing harm to the eye. The illumination of the intraocular space was investigated using porcine eyes. RESULTS: The illumination of porcine eyes with the modified LEDs was bright and homogeneous. Measurements and subsequent calculations proved that the expected thermal load and photochemical hazard were very low for human eyes. CONCLUSION: The hitherto existing experimental results on porcine eyes and the theoretical considerations on human eyes were found to be positive; therefore, it is expected that this new fiberless chandelier LED endoilluminator will prove to be advantageous for human patients. It promises a reduced number of incisions with a simplified handling and need to add handheld light sources only if minimal intensity oblique illumination is helpful together with the chandelier illumination. This contributes to a significant reduction of phototoxicity risks and additionally there is a chance for a cost reduction because expensive xenon or mercury lamps are no longer necessary. These expectations have to be verified by further studies on human eyes.