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The purpose of this project is to apply and optimize a conventional streak retinoscope connected to a smartphone in order to demonstrate and record retinoscopic techniques, related phenomena, typical examination errors in a standardized environment and to use this set-up to produce instructional video clips. The videos enhance and improve the trainer-trainee interaction by instantly visualizing the optical phenomena on the integrated monitor of the retinoscope.A smartphone (iPhone 6, Apple, Cupertino, CA, USA) is reversibly connected to a Beta 200 streak retinoscope (HEINE, Herrsching, Germany) via a coupling plate. This allows visualization of the optical phenomena on the screen of a smartphone, which can also be used for recording. To stabilize the recording conditions, the battery handle of the retinoscope is connected to a 3-axis gimbal (Zhiyun Crane Plus, Zhiyun, Guilin, China). In this way the examination unit can be rotated around all axes without any relevant changes in distance. A software-based post-processing (Adobe Premiere Pro CC 2017, Adobe Systems Software Ireland Limited, Dublin. Ireland) of the video sequences almost completely eliminates motion artefacts.With the aforementioned experimental set-up, the following optical phenomena have so far been documented as videos, which are available online: flashing point, with-movement and against-movement, scissors phenomenon, cataract, astigmatic ametropia and refraction scotoma.For the first time smartphone video retinoscopy allows optical phenomena to be presented to the examiner (trainee) and trainer at the same time and to produce realistic instructional videos of high quality with comparatively little effort.

Due to current demographic trends, the prevalence of mild cognitive impairment and dementia is expected to increase considerably. For potential new therapies it is important to identify patients at risk as early as possible. Currently, there is no population-based screening. Therefore, identification of biomarkers that will help screen the population at risk is urgently needed. Thus, a literature review on retinal pathology in neurodegenerative diseases was performed.PubMed was searched for studies published up to August 2016 using the following keywords: "mild cognitive impairment", "dementia", "eye", "ocular biomarkers", "OCT" and "OCT angiography". Relevant publications were selected and summarized qualitatively.Multiple studies using noninvasive in vivo optical coherence tomography (OCT) imaging showed nonspecific retinal pathological changes in patients with neurodegenerative diseases such as mild cognitive impairment, Alzheimer's and Parkinson's disease. Pathological changes in macular volume, optic nerve fiber layer thickness and the ganglion cell complex were observed. However, based on available evidence, no ocular biomarkers for neurodegeneration which could be integrated in routine clinical diagnostics have been identified.The potential use of OCT in the early diagnostic workup and monitoring of progression of neurodegenerative diseases needs to be further explored in longitudinal studies with large cohorts.

The gold standard for the assessment of the vitreoretinal interface (VRI) is high resolution OCT. It is therefore essential to select the appropriate scan modalities to detect all morphological changes in different diseases, not only at the VRI, but also in all layers of the retina and in the foveal and parafoveal areas. These can be raster scans, radial scans or "en face" scans. Morphological changes at the VRI and especially in the outer retinal layers are good prognostic factors in high resolution OCT for the success of surgery for vitreomacular interface disorders. The following article gives an overview of current OCT procedures as well as correlations between morphological and functional findings.

Optic disc oedema describes blurred optic disc margins. It describes an unspecific clinical sign with various possible underlying causal mechanisms. The correct diagnosis and the detection of the underlying disease is however of special clinical importance. This article summarizes the most important differential diagnoses and gives advice to find the correct diagnosis.

Fundus autofluorescence (FAF) imaging allows for non-invasive mapping of changes at the level of the retinal pigment epithelium/photoreceptor complex and of alterations of macular pigment distribution. This imaging method is based on the visualisation of intrinsic fluorophores and may be easily and rapidly used in routine patient care. Main applications include degenerative disorders of the outer retina such as age-related macular degeneration, hereditary and acquired retinal diseases. FAF imaging is particularly helpful for differential diagnosis, detection and extent of involved retinal areas, structural-functional correlations and monitoring of changes over time. Recent developments include - in addition to the original application of short wavelength light for excitation ("blue" FAF imaging) - the use of other wavelength ranges ("green" or "near-infrared" FAF imaging), widefield imaging for visualisation of peripheral retinal areas and quantitative FAF imaging.

Recent developements in OCT technology using high speed acquisition and calculation of consecutive scans (SSADA = split spectrum amplitude decorrelation algorithm) have resulted in the possibility to demonstrate retinal and choroidal vessels in the macula. This new technology of "OCT angiography" thus allows the non-invasive and rapid (within seconds) reconstruction of the three-dimensional structure of the retinal and choroidal vascularisation. There are still limitations caused by movement artefacts, superposition of superficial retinal vessels at the RPE level or insufficient three-dimensional imaging, but the first experience with this new method and especially the correlations with the current standard diagnostic procedure fluorescein angiography shows that especially for vascular changes which are predominantly in one retinal layer (e.g., the inner retina) like in diabetic retinopathy or retinal vein occlusions, a very good correlation can be seen. Also in MacTel type 2 patients the proposed vascular changes in the deeper capillary network of the retina can be visualised very well with OCT angiography. In contrast, more three-dimensional vascular changes like the neovascular complex in exsudative AMD need a more sophisticated diagnostic analysis strategy, which has still to be developed. However, the first experience also demonstrates that fluorescein angiographic differentiation can also be seen in OCT angiography. In addition, the new technology gives additional information about the choroidal and outer retinal changes in these pathologies, which may result in a better understanding of the underlying pathologies.

The aim of this study was to investigate alterations in the neurosensory retinal morphology secondary to acute retinal ischaemic conditions. The observations were documented by spectral domain optical coherence tomography (SD-OCT, Heidelberg Engineering) and fundus autofluorescence (FAF) imaging. In addition, the occurrence of an additional hyperrefelctive band in the outer corneal layers is described. This observation was made during the evaluation of OCT images of patients with an acute loss of vision due to retinal ischaemia.SD-OCT images and FAF were used to observe the retinal structure of 26 subjects (36 to 96 years) with acute monocular visual impairment due to central retinal artery occlusion (CRAO), branch retinal artery occlusion (BRAO), anterior ischaemic optic neuropathy (AION) or impending central retinal vein occlusion were included. The main focus of attention was set on the transition of the outer nuclear layer (ONL) to outer plexiform layer (OPL). Furthermore measurements of the retinal thickness at the fovea, parafoveal and within the retinal layers were acquired and compared to corresponding points of the non-affected eyes. SD-OCT images were acquired with a combined SD-OCT and scanning laser ophthalmoscope (cSLO) imaging system using a linear cross hair scan and a 6 line radial scan of 6 mm length (ART mode on; average of 20 frames).SD-OCT revealed an additional highly reflective band located within the OPL. Morphological characteristics of this hyperdense band were a decreasing intensity with distance from the fovea, partially segmental occurrence and manifestation limited in time. FAF showed areas of increased and decreased signal intensity within the vessel arcade at the posterior pole. The regions of decreased FAF corresponded to perivenous regions and resemble the "frosted branches" sign seen in fluorescein angiography in patients with ocular ischaemia.The additional hyperreflective band observed in SD-OCT could represent a marker for retinal ischaemia in subjects without the presence of a complete vascular occlusion. The mid retinal localisation of the band within the OPL is situated at the locus of transition from retinal to choroidal oxygen supply where oxygen diffusion is weakest. Histopathologically the observed structure could represent activated microglial tissue induced by the hypoxia driven upregulation of inflammatory molecules aimed at ischaemia repair.

An early diagnosis is crucial for the outcome of mucous membrane pemphigoid (MMP). The sensitivity of the so-called diagnostic gold standard, direct and indirect immune fluorescence (DIF/IIF) ranges from 30 to 80 %, and is thus lower than desirable. Moreover, conjunctival biopsy, mandatory in most cases, entails the risks of exacerbation. The purpose of this study is to establish the contribution of non-invasive in vivo confocal microscopy to the recognition of MMP.We examined the conjunctiva of ten patients and ten control subjects with the confocal microscope Heidelberg Retina Tomograph II/Rostock Cornea Module and checked for differences in qualitative and quantitative structure of the connective tissue.Pemphigoid patients showed an increase and/or aggregation of reticular connective tissue with hyperreflective strands in the substantia propria, as well as an increased subepithelial fibrosis compared to controls. The basal membrane zone was thicker and more hyperreflective than in the healthy subjects.In-vivo confocal microscopy may serve as a useful additional diagnostic method in the detection of MMP.

Nowadays, further developments in the field of intraocular lenses offer a higher level of spectacle independence for our patients. As light gets scattered on different focal points a wider range of defocus is created. This greater defocus area makes it more difficult for us to determine the objective or subjective refraction. This contribution is concerned with the difficulties of measuring visual acuity in different intraocular lens designs and different measurement distances. Measuring refraction after implantation of a multifocal intraocular lens is a complex procedure and the experience of the examiner plays a crucial role. Retinoscopy, keratometry and the defocus curve are reliable methods for testing, while the auto refractometer, bichromatic testing and the cross-cylinder have limitations.

Reproducibility of subjective refraction measurement is limited by various factors. The main factors affecting reproducibility include the characteristics of the measurement method and of the subject and the examiner.This article presents the results of a study on this topic, focusing on the reproducibility of subjective refraction measurement in healthy eyes. The results of previous studies are not all presented in the same way by the respective authors and cannot be fully standardized without consulting the original scientific data. To the extent that they are comparable, the results of our study largely correspond largely with those of previous investigations: During repeated subjective refraction measurement, 95% of the deviation from the mean value was approximately ±0.2 D to ±0.65 D for the spherical equivalent and cylindrical power. The reproducibility of subjective refraction measurement in healthy eyes is limited, even under ideal conditions.Correct assessment of refraction results is only feasible after identifying individual variability. Several measurements are required. Refraction cannot be measured without a tolerance range. The English full-text version of this article is available at SpringerLink (under supplemental).

Macular telangiectasia type 2 is characterized by atrophic alterations of the central retina which is accompanied by a defined vascular phenotype. The disease manifests within an oval central retinal area the size of approximately two disc diameters, with a topographic predisposition temporal to the foveal center. Funduscopy reveals reduced retinal transparency, crystalline deposits, mildly ectatic capillaries, thickened venules and retinal pigment plaques. Secondary neovascularization and macular holes may occur during the disease course. Fluorescein angiography usually shows a diffuse leakage and often ectatic capillaries. On optical coherence tomography (OCT) examination, hyporeflective cavities and focal atrophy of the photoreceptor layer represent a frequent finding. A characteristic sign is an increased (para) central signal on fundus autofluorescence imaging due to a reduced density of macular pigment.

There are some reports showing isolated cases of drusen regression after pars plana vitrectomy (ppV) with peeling of the internal limiting membrane (iLM). Drusen characteristics after iLM peeling was investigated in this study.The data of 527 patients who had received iLM peeling between 2004 and 2012 were retrospectively collected and those patients with retinal drusen were selected for the study. Fundus photographs before and after vitrectomy due to a macular hole or epiretinal gliosis were compared and drusen arrangement in the peeling site was analyzed. The aim of the study was to show whether there was drusen regression 2-5 months after surgery.Out of the 527 patients 11 showed central macular drusen, 4 with confluent large drusen (63 µm diameter) and 7 with small hard drusen (≤ 63 µm diameter). One patient showed drusen regression after iLM peeling without any changes in the other eye and all other patients showed no differences in the drusen findings (n = 6) or even some additional drusen (n = 4) without drusen alterations in the other eye.The results of this study could not confirm some reports showing drusen regression after iLM peeling in the peeling site in general and there was only one single case of central drusen regression.

Posterior uveitis comprises a heterogeneous group of diseases with inflammatory alterations of the posterior fundus and is a common cause of visual impairment and blindness. The goal of this study was to evaluate the diagnostic value of wide-field fundus autofluorescence (FAF) in patients with non-infectious posterior uveitis and chorioretinal alterations.In this study 73 eyes from 51 patients were included. Best-corrected visual acuity, wide-field color and FAF images achieved by a wide-field scanning laser opththalmoscope (SLO, Optomap P200Tx, Optos PLC, Dunfermline UK) and a full ophthalmological examination were obtained from each patient. A systematic analysis of chorioretinal alterations detected with FAF and color images was conducted followed by the evaluation of the diagnostic information of wide-field FAF compared to the clinical finding and wide-field color images.Of the 73 eyes included in the study 52 showed peripheral alterations. In 32 cases wide-field FAF images revealed a greater number and more extensive chorioretinal alterations than the corresponding wide-field color images of the posterior fundus.In this study wide-field FAF images showed more chorioretinal alterations than seen in funduscopy or in color SLO images. Therefore, wide-field FAF images offer important additional information for detection and documentation of peripheral and central chorioretinal alterations.

For an implemented ophthalmological screening within a German long-term cohort study (National Cohort) simple and effective methods for an examination of visual acuity and for non-mydriatic retina photografies should be evaluated. Furthermore standard operating-procedures (SOP) should be developed.In the years 2011 and 2012 pinhole visual acuity measurements and automated retina photographies (DRS, CenterVue S. p. a., Padua, Italy) were made at three different epidemiological study centers within Germany. Furthermore, anterior segment images were taken by the camera. Standard operating procedures (SOP) regarding the ophthalmological screening were developed and evaluated within the study. The main question was whether it is possible to implement the screening methods within the National Cohort. Further main outcomes were quality and interpretability of the taken images.457 subjects (914 eyes) were examined within the investigation. Median VA was 0.8 for right and left eyes (p 0.42). Image quality of the photographies was good in 491 cases (54 %), fair in 239 cases (26 %) and bad in 179 cases (20 %). The usability of the images was without limitations in 686 cases (75 %), limited in 152 cases (17 %) and not given in 71 cases (8 %). Increasing age of the subjects was slightly correlated with decreasing image quality (r = 0.26) and decreasing image usability (r = 0.2). Anterior segment photographies were usable in 176 eyes (56 %).The developed screening method fulfilled the specifications of the National Cohort. The used pinhole visual acuity examination was fast and cheap. Image quality and usability of the retina photographies could be improved with prolonged pupil recovery times. The quality of the anterior segment images could not fulfill the expectations and were taken out of the further examinations of the ophthalmological screening. The written SOP showed good acceptance within the investigators' daily routine. The ophthalmological screening within the National Cohort generates information (e. g., pathologies of the vessels or of the retina) which are useful not only from an ophthalmological point of view.

Fundus autofluorescence is a novel technique that gives us information about the RPE cells by evaluating the distribution of lipofuscin in the retina. The purpose of our study was to evaluate the diagnostic abilities of OCT, RTVue and fundus autofluorescence in predicting the progression of dry AMD.In our study 37 dry AMD patients were enrolled: 22 of them with druses and 15 with developed geographic atrophy. They all underwent complete ophthalmological examinations including OCT and autofluorescence. We used the RTVue OCT programmes HD line, Cross line, EMM5 and EMM5 progression in all cases. The autofluorescence was recorded with the help of the Canon CX1 fundus camera.OCT images in the AMD patients with dry AMD and large druses showed typical undulations in the RPE/choroid line and occasionally drusenoid detachment of the RPE. Autofluorescence showed different patterns. The confluent reticular autofluorescence was associated with the development of neovascular membranes. In geographic atrophy patient OCTs showed diminished retinal thickness measured with EMM5. On autofluorescence the findings at the border zone atrophic/normal retina were of particular importance. The diffuse increased autofluorescence in that area was considered to be a sign for further atrophy progression.Our results point out that OCT in combination with autofluorescence is important in following the progression of dry AMD. Pathological autofluorescence at the border of atrophic lesions is an important sign for disease activity. Although both OCT and autofluorescence visualise the changes in RPE, autofluorescence is of key importance in predicting the development of the disease.

During the last years, optical coherence tomography (OCT) has evolved to an important diagnostic tool in ophthalmology. In addition to ophthalmoscopy and the topographic visualisation of pathologies of the posterior part of the eye by fluorescein and indocyanine-green angiography, OCT adds complementary tomographic information on the retinal structures. First generation (time domain) OCT machines already generated pictures that resemble histological cross-sections of the retina. With the new OCTs of the spectral/frequency/Fourier domain generation, topographic and tomographic information can be presented side-by-side or in combination, thereby increasing the accuracy of the localisation of the visualised structures. Because of its non-invasive methodology without contact to the patient's eye and the faster acquisition times with increasing resolution, the OCT has become a valuable instrument in the modern anatomic and structural diagnostics of the macula. Functional statements are not yet possible in a comprehensive manner, but first steps have been made with the interpretation of structural information from high-resolution images. In this paper, the emerging possibilities from a widespread use of the OCT, as well as the limitations of this diagnostic technique, are discussed.

Refractive errors are the most common visual problem in children apart from squinting. Indications for spectacles include amblyopia prophylaxis and treatment, strabismus, myopia and reading disorders. Objective refraction by retinoscopy is the central part of prescribing spectacles to children. A slight under correction (maximum of 0.5 dpt in cases with and 1.0 dpt without squint) can be considered in hyperopia only. Myopia, astigmatism and anisometropia must be fully corrected. Any prescription must mention "MA=PD" and "plastic lenses" as well as "high bifocal" if needed. Information to the parents is essential for good compliance of spectacle wear. Step-by-step instructions and a list of possible errors will be given.

Ocular ischemic syndrome (OIS) is a group of ocular diseases caused by chronic artery occlusion usually involving the internal carotid artery. Patients suffer from visual loss and pain. OIS is a rare disease which can be confounded with diabetic retinopathy or an older central retinal vein occlusion. The only therapy is to treat the neovascular complications. Due to the high mortality of OIS patients, medical and neurological examinations are mandatory. We discuss the clinical findings and diagnostic and therapeutic options of OIS patients in this paper.

Retinal vein occlusions are a common vascular disease of the eye. Ophthalmological diagnostic procedures and imaging are important for the prognosis of the disease, as are the systemic work-up and therapy. Besides routine ophthalmic tests (visual acuity, slit lamp examination, funduscopy) a work-up for glaucoma such as intraocular pressure, visual field or 24 h IOP profile is useful as a diagnostic procedure. Furthermore, new diagnostic and imaging tests such as central corneal thickness and optic nerve head imaging by Heidelberg retina tomography or optical coherence tomography (OCT) should be considered for glaucoma evaluation. Optical coherence tomography also plays a major role in treatment monitoring of macular edema secondary to retinal vein occlusions. Fluorescein angiography is well established and can provide information with regard to size and extent of the occlusion, degree of ischemia, areas of non-perfusion and neovascularization, as well as macular edema.

The Vision Screener® (Plusoptix) was developed for the recognition of amblyogenic refractive errors without cycloplegia. The aim of this study was to evaluate the sensitivity and specitifity for the detection of amblygenic refractive errors in preschool children. Furthermore it was investigated whether small angle strabismus as another cause for amblyopia could be detected by manual evaluation of corneal reflex images on printouts.83 children aged between 0.5 and 6 years without strabismus had undergone 3 measurements without cycloplegia with the Vision Screener before cyclplegic retinoscopy was performed. In a second group of 72 children with orthotropia or a manifest strabismus10° the position of the eyes without correction was evaluated in a complete orthoptic and ophthalmological examination. Three measurements with the Vision Screener were performed in non-cycloplegic status. The centre of the "cloud of viewing directions" was determined on print-outs and the distance to the points of origin (middle of pupil) measured for each eye. The sum of distances of right and left eyes was taken for determination of total deviation and the assymetry was calculated by the difference of distances of the right and left eyes.There was a total sensitivity of 75% (specifity 91%) for amblyogenic refractive error (prevalence: astigmatism 22%, hyperopia 6%, anisometropia 6%). A change of threshold criteria increased the total sensitivity to 86% and 93%, whereas specifity was lowered to 80% and 76%, respectively. Eight children showed a manifest strabismus. In 75% of these cases the determined deviation of corneal reflex images in the horizontal direction was outside of the normal range; analysis of asymmetry showed an abnormal result in 37.5% of the cases.The examination using the Vision Screener may detect refractive errors and partially small angle strabismus as amblyogenic risk factors; however, additional tests should be added for screening examinations. An ophthalmological examination including cycloplegic retinoscopy cannot be replaced. Despite acceptable sensitivity and specifity the major portion of positively screened children will be without pathological findings at cycloplegic controls, because the amount of "false-positive" results exceeds the amount of "true-positive" results based on a prevalence of 5% for amblyopia.

A 69-year-old female patient presented with unilateral optic nerve atrophy and visual loss. The visual field examination showed not only a subtotal visual field loss in the affected eye but also a visual field defect in the other eye which was classified as an anterior junction syndrome. Cranial MRI revealed a tuberculum sellae meningioma which was treated surgically.

Diabetic macular edema (DME) and proliferative retinopathy are common causes for blindness in middle-aged patients. The gold standard for treatment has been laser coagulation. Limitations of this therapy are refractive DME, ischaemic diabetic maculopathy and complications after laser application. The need for a non-destructive and effective strategy has led to investigations regarding vascular endothelial growth factor (VEGF) inhibitors for reduction of vessel leakage and oedema formation. VEGF antibody fragments have been approved for age-associated macular degeneration (AMD) in different countries and have proved to be safe and effective. Trials for different anti-VEGF compounds are nearing completion or are completed. Published data show a superiority of anti-VEGF therapy compared to laser coagulation. In the present article, data regarding dose, injection scheme and practicable application form are reviewed.

Staining of the retinal surface has improved the intraoperative removal of semitransparent membranes during macular surgery. The purpose of this study was to evaluate the clinical experiences with brilliant blue G (BBG) staining of the retinal surface.BBG (Brilliant peel, Fluoron) was applied during vitrectomy and macular surgery in 43 patients. In 47 % there was a macular hole (MH), whereas 53 % had epiretinal membranes (ERM). Intraoperatively BBG was applied on the retinal surface under infusion or air conditions for 30 - 60 s. In MH the internal limiting membrane (ILM) and in ERM the membrane was removed. Postoperatively all patients were examined on average after 9 weeks.Although intraoperative BBG staining was less intensive compared to ICG staining, the staining was sufficient to safely remove the semitransparent membranes in all cases. In all patients with MH hole closure was achieved, and in 96 % with ERM the metamorphopsiae decreased. The mean decimal visual acuity increased from 0.25 ± 0.13 to 0.37 ± 0.20 (p0.05) and improved in 63 % of the patients. Clinically, there were no toxic side-effects from BBG staining.BBG allowed a complete and selective staining of the retinal surface. Thus, ILM and ERM could be removed safely during macular surgery. No clinical retinal toxicity was observed.

Several systemic cardiovascular (CV) risk assessment algorithms exist, of which the ESC HeartScore, Framingham and PROCAM are the most frequently applied in Germany. The risk estimates generated differ and take a number of different risk factors into consideration. Due to existing homology of retinal vessels and brain vessels, eye fundus examination is a promising approach to improving risk prediction. Large cohort studies investigated retinal vascular changes, including arteriovenous ratio, as well as signs of retinopathy such as cotton-wool spots, microaneurysms, or retinal hemorrhages for their ability to predict systemic cardiovascular events. While signs of retinopathy proved to have high predictive power (but are rarely diagnosed,) the retinal vascular changes investigated could contribute little to enhancing systemic CV risk prediction. A number of new and promising approaches based on static and dynamic retinal analysis exist, but still need to be validated prospectively.

The degree of retinal microangiopathy is important foran estimation of the vascular risk and for the optimisation of therapy in hypertensive and diabetic patients. Retinal microangiopathy may be determined by examination of the retinal fundus. We examined the reliability of the ophthalmoscopic diagnosis and of the telemedical judgement of fundus images in relation to the presence and the degree of retinopathy.This comparative observational study included 47 inpatient hypertensive and/or diabetic subjects. The fundus was judged ophthalmoscopically and subsequently, a fundus image was generated by use of a KOWA camera. The images were sent to the Interdisciplinary Center of Ophthalmologic Preventive Medicine. The reliability of the two diagnostic methods was calculated for one of the two eyes, which was selected by a random generator.The largest concordance of the two diagnosis methods was achieved, in descending order, for retinal bleeding, stage of diabetic retinopathy and the papilla findings. Additionally, there were no differences for the stage of hypertensive retinopathy und tortuosity. The reliability of arterio-venous nicking related to the right and the left eye was low or absent, respectively.The teleophthalmologic diagnosis achieves good results as compared to the ophthalmoscopic judgement in relation to retinopathy assessment criteria.

Cellular metabolism can be evaluated using time-resolved autofluorescence. Because the fluorescence of ocular tissue is an accumulation of the fluorescence of several endogenous fluorophores, it is hard to determine the influence of a single fluorophore. In branch retinal artery occlusion, metabolic changes can be compared with normal tissue.Time-resolved autofluorescence was measured in two patients in two spectral channels, K1 (490-560 nm) and K2 (560-700 nm), and was 3-exponentially approximated and compared with representative results of a healthy eye.In K1, lifetime τ1 in the undersupplied tissue was weak, but τ2 was strongly elongated compared with the healthy tissue. In K2, the distribution of τ2 was identical in both tissues. In the healthy eye, there was an equal distribution of all lifetimes in corresponding fundus regions.The elongation of τ1 in undersupplied tissue is probably caused by a reduced contribution of protein-bound FAD. The elongation of τ2 (about 500 ps) in healthy tissue, compared to about 1.5 ns in undersupplied tissue, is probably caused by protein-bound NADH, which is formed in glycolysis.

Ocular manifestations of acute lymphoblastic leukemia (ALL) are manifold. A funduscopic image which shows optic disc edema, serous retina detachment, intraretinal hemorrhages and infiltrations indicates an extramedullary recurrence of ALL. Reduction of visual acuity in patients in remission can often be one of the first signs of ALL relapse and can also occur without systemic changes. Regular ophthalmologic and oncologic controls are of great importance. The early recognition of ALL relapse is important to initiate early treatment. However, the prognosis for visual acuity is usually low.

Beschrieben wird der Fall einer 27-jahrigen Patientin, die sich aufgrund einer zufallig festgestellten, asymptomatischen, retinalen Gefasveranderung in unserer Klinik vorstellte. Aufgrund der typischen funduskopisch erkennbaren Veranderungen wurde von uns die Diagnose einer arteriovenosen Malformation gestellt. Die weitere Diagnostik erbrachte keinen Anhalt fur das Vorliegen einer zerebralen oder fazialen Beteiligung.

High-definition raster scanning spectral-domain optical coherence tomography (SD-OCT) allows a precise assessment of retinal layers and a more detailed detection of subtle morphological alterations. The aim of this study was to observe such changes in patients with neovascular age-related macular degeneration (nAMD) under anti-VEGF therapy and to evaluate if they show characteristic and reversible properties.The study included 20 consecutive patients with untreated nAMD. SD-OCT with an axial resolution of 6 µm and a scan velocity of up to 25,000 A-scans/s was used for high-resolution imaging of the macular region at baseline and at months 1 and 3. Characteristic changes in the retinal microstructure were documented and analyzed.Obvious morphological changes as well as discrete intraretinal alterations showed a clear improvement until the third month following the initial ranibizumab injection. Destructions of the neurosensory retina and the outer retinal layers were partly reversible and significantly reduced after treatment was applied.SD-OCT was able to detect additional information on specific morphological alterations within the retina. These changes showed a considerable reduction under consistent treatment indicating their potential value for monitoring treatment success in antiangiogenic strategies.

The optimal treatment approach for traumatic macular holes (TMH) is still controversial. We report two cases of spontaneous closure of TMH. In the first patient, closure resulted in an increase in visual acuity from 0.2 to 0.8. In the second case, no increase in visual acuity was detectable despite spontaneous closure of the TMH within a few days after the trauma. This may be explained by an irreversible damage of the photoreceptors and retinal pigment epithelium. In patients with TMH, a waiting approach should be considered because of the possibility of spontaneous closure of TMHs.

Optical coherence tomography (OCT) is new diagnostic procedure that has rapidly evolved in the last years. The recently developed spectral domain OCT allows one to increase the imaging speed by a hundred times compared to the first generation time domain OCT and enables three-dimensional imaging as well as real-time imaging of fast moving structures. Volumetric imaging improves the quantitative measurement of morphology and the evaluation of temporal changes. In addition, an exact correlation with images acquired with other imaging modalities is possible. Real-time imaging enables also the use of OCT during examinations with the slit-lamp and during ophthalmological surgery.A spectral domain OCT was adapted to a slit lamp. 70 patients (91 eyes) were examined at the anterior or posterior segment of the eye. Images of healthy structures and different pathologies were compared to OCT images obtained with Stratus 3, Spectralis, and the SL-OCT. To demonstrate the feasibility of OCT during surgery, spectral domain OCT devices working with 20,000 and 210,000 A scans per second were coupled by specially developed optics to the camera port of a surgical microscope. The device was tested with phantoms and enucleated pig eyes.A 5 kHz spectral domain OCT can image the retina during slit lamp-based indirect ophthalmoscopy with a quality similar to that of the Stratus 3. In addition, relevant structures of the anterior segment were imaged. Here, compared to commercially available devices, the imaged field was smaller and the angle of the anterior chamber was not directly visible due to the 830 nm wavelength, which had to be used for retinal imaging. Through the surgical microscope, a volumetric imaging of epithelium, Bowman's, Descemet's membranes, limbus, iris, lens, conjunctiva and sclera was demonstrated with several tens of centimetre working distance. Instruments and incisions in the cornea were visualised with 20 microm precision. Real-time imaging and visualisation of volumetric OCT data were also demonstrated. In principle, all technical problems of an intraoperative use of OCT have been solved and a clinical trial will start in the near future. OCT has the potential to improve the precision of surgical interventions and may even enable new interventions.

Biometry has the potential to improve refractive outcomes of cataract surgery in developing countries. However, the procedure is difficult to carry out in remote areas.The feasibility of automated biometry using portable devices was assessed in an eye camp in a remote Kenyan community and reasons for failure were documented. PC-IOLs in the range of 17-27 dioptres (dpt) were implanted and a model was created to predict spherical refractive error if a standard 22 dpt lens had been used.In 104 out of 131 eyes (80%) biometry was possible. Failure to obtain K-readings in eyes with coexisting corneal pathology was the main limiting factor. The calculated mean IOL strength to achieve emmetropia was 21.56 dpt with a SD=1.96 (min: 14.78 dpt, max: 27.24 dpt). If 22 dpt lenses had been implanted around 20% would have had an error of more than 2 dpt and 7% an error of more than 3 dpt.Biometry is a challenging procedure in remote areas where comorbidities are common. However, without biometry and implantation of different IOL powers poor refractive outcome can be expected in around 20% of patients.

Hereditary retinal dystrophies comprise a heterogeneous group of inherited retinal disorders with variable clinical presentation and multiple associated genes. Clinical diagnosis and differential diagnosis are difficult. The purpose of the current paper is to provide guidelines for an effective diagnostic approach.A literature search was carried out and our own data on clinical (n = 3200) and molecular genetic (n = 4050) diagnosis of patients with retinal dystrophies were evaluated.For an early diagnosis it is of importance to include inherited retinal dystrophies in the differential diagnosis of unexplained visual disturbances. The most important clinical test is the full-field electroretinogram (ERG), which allows detection or exclusion of generalised retinal dystrophies. If the full-field ERG is normal, a multifocal ERG will distinguish macular dystrophies. Fundus autofluorescence, near-infrared autofluorescence and high resolution optical coherence tomography improve the early diagnosis because morphological alterations can be detected prior to their ophthalmoscopic visibility. In addition, these non-invasive imaging techniques reveal new phenomena which are important for the differential diagnosis and follow-up of retinal dystrophies as well as for an improved understanding of their pathogenesis. Routine molecular genetic diagnosis is available for an increasing number of retinal dystrophies. A succinct clinical diagnosis is a prerequisite to allow selection of the gene(s) to be analysed. If genetic testing is indicated, a human geneticist should be involved for counselling of the patient and possibly further family members and initiation of the necessary steps for DNA testing.The combination of electrophysiological testing, retinal imaging and molecular genetic analysis allows a differentiated diagnosis of inherited retinal dystrophies and an individual counselling of patients. If inherited retinal dystrophies are suspected, a detailed examination in a retinal centre specialised on inherited retinal dystrophies is recommended.

At present time domain optical coherence tomography (TD-OCT) plays a less important role in glaucoma diagnostics and is used mainly for macula diagnostics. The Fourier domain optical coherence tomography (FD-OCT) with enhanced resolution has new options to detect glaucoma changes. This new technology is referred as frequency domain or spectral domain OCT. This paper will present current and new options of OCT in glaucoma diagnostics. Measurements of the optic nerve head and the retinal nerve fiber layer thickness using this new technology have been shown to be reproducible. Devices which use TD-OCT (e.g. Stratus-OCT) have a lower resolution than devices that use FD-OCT (e.g. RTVue-100; 10 microm versus 5 microm axial resolution). A new option is the evaluation of the retinal ganglion cell complex. The measurement of the optic nerve head and the retinal nerve fiber layer using FD-OCT are promising for glaucoma diagnostics. How this new technology, especially the ganglion cell complex analysis is comparable to other technologies and whether it is helpful for glaucoma diagnostics and monitoring of management will be evaluated in future studies.

The aim of this study was to simulate the effect of illuminance on retinal image quality before and after LASIK.Wavefront sensing was performed in eighteen eyes of 12 patients before and one month after uncomplicated LASIK using a Hartmann-Shack sensor. A sigmoid curve was fitted to pupillometry data obtained at 4, 0.4 and 0.04 lux. Based on the sigmoid fit, pre- and postoperative wavefront errors were simulated for different pupil diameters over a corresponding range from 10 (-2) to 10 (2) lux. Retinal image quality was described by computation of the visual Strehl ratio based on the optical transfer function (VSOTF) for a spectacle correction preoperatively and for the uncorrected eye postoperatively.At an illuminance of 1 lux the mean pupil diameter was 4.81 +/- 0.91 mm and log VSOTF dropped from -0.47 +/- 0.29 to -1.18 +/- 0.32 (p0.001) after LASIK. The steepest pupil-induced decrease of VSOTF occurred preoperatively at 0.67 +/- 0.26 lux (range 0.2 - 1.58 lux). After LASIK, L (crit) on average was 0.96 +/- 0.53 lux (p0.05; range 0.2 - 1.78).The steepest pupil-induced decrease of retinal image quality occurred in the high mesopic range, however, there was intersubject variability.

Pathological findings and clinical course of retinopathy of prematurity (ROP) are often documented with hand drawings. The use of software-based standardised symbols for ROP staging leads to improved documentation quality.We developed graphical symbols for all ROP stages as well as plus disease. All of the symbols were integrated into a java-based application as a particular ROP category of a complete symbol library for retinal changes. The symbols can be placed on a schematic retina with a mouse click. Using anchors each symbol can be individually adapted to the specific finding (size, position, shape).The use of standardised symbols in a software package allows the computer-aided manufacturing of graphically high-quality documentation in affordable time. The distinct assignment of all symbols to the ROP stages prevents misinterpretation and sketchy, illegible hand drawings.The digital documentation of pathological changes of ROP provides an easy, economic and standardised method to record retinal findings.

The aim of this study was to compare macular thickness measurements obtained from time-domain optical coherence tomography (OCT) and spectral-domain OCT to evaluate their agreement.Fifty randomly assigned subjects were included. Twenty-five were male, twenty-five female. In all cases both eyes were measured. Serial measurements were obtained from time-domain (StratusOCT, Zeiss) and spectral-domain OCT (Heidelberg Engineering, Germany). Total and regional macular thicknesses were obtained from both machines. Their agreement was estimated by Bland Altman plots.The foveal and total macular thicknesses measured by 3D OCT were significantly greater than those measured by StratusOCT (p0.001).While both time-domain and spectral-domain OCTs are reliable for macular thickness measurements, spectral-domain OCT delivers significantly higher values for macular thickness compared to the time-domain OCT. Macular measurements obtained from the two OCT systems may not be used interchangeably.

We describe the establishment of a new digital integration method (DIM) for the anatomically precise and objective correlation of OCT and FLA. The aim of the study was to evaluate the clinical impact of DIM and deduce possible new knowledge in unclear angiographic findings.DIM uses a newly developed software for the integration of OCT and FLA images of the same date. Corresponding vascular bifurcations and OCT scan position are marked in OCT and FLA images. Pathological areas in OCT or FLA can be marked and compared. A fundus enhancement system (FES) was developed for a better fundus image quality in OCT. Using a retinal tracking system (RTS) eye movements can be compensated. DIM was evaluated in 225 patients with macular diseases.Using FES, the DIM was successful in 95 % of the patients in contrast to 25 % without FES. Using the video system of RTS eye movement artefacts could be compensated in all patients. Cases with clear angiographic findings showed a high correspondence (66 %) with the OCT findings. A discrepancy between FLA and OCT findings was found in 33 %, especially in leakages of unknown origin. DIM was of high value in age-related macular degeneration (AMD), detecting a heterogeneous morphology of serous, solid RPE detachments, retinal cystoid formation and choroidal neovascularisation (CNV) and differentiating it in a precise topography. The lesion size of classic CNV with a hypofluorescent halo was in OCT always larger than in FLA.Through the correction of the eye movement artefacts by DIM and FES, a fundamental weak point in the previous OCT pictures is counterbalanced. Using DIM the OCT scan position for the follow-up can now be assessed in a safe and reliable manner which is mandatory for the evidence of OCT studies. The detection of precise morphology (serous RPE detachments) in angiographically unclear phenomena can lead to treatment consequences, e. g., avoiding contraindicated areas in photodynamic therapy. Using the new morphological information new knowledge is obtained on uncertain angiographic phenomena by this integration method (DIM).