OCT and IOP findings in a healthy worker cohort: results from a teleophthalmic study in occupational medicine

Graefe's Archive for Clinical and Experimental Ophthalmology https://doi.org/10.1007/s00417-019-04457-1 MEDICAL OPHTHALMOLOGY OCT and IOP findings in a healthy worker cohort: results from a teleophthalmic study in occupational medicine Elisabeth Grau 1 & F. Horn 1 & U. Nixdorff 2 & G. Michelson 1,3 Received: 30 April 2019 / Revised: 26 August 2019 / Accepted: 28 August 2019 # Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract Purpose To avoid significant loss of vision in employees, the working population could be examined with ophthalmic methods as OCT and IOP measurement for detection of serious eye diseases. The value of “virtual eye clinics” in occupational preventive medicine has been previously shown. We used a telemedical approach to gather epidemiological information about prevalence of eye diseases such as glaucoma, ocular hypertension, hypertensive retinopathy, diabetic retinopathy, epiretinal membrane, AMD, adult vitelliform maculopathy, cystoid maculopathy, choroidal nevi, and macular drusen. Methods The study included 931 people ranging from age 39 to 65 years. Using a telemedical approach, all medical examinations and the ophthalmic examination were performed by a technician using an optical coherence tomography (SD-OCT) and a pulse air tonometer. The data were saved in the web-based patient chart MedStage® of the Talkingeyes® Collaboration Network. Results We found a high prevalence of eye diseases in a group representative for the working-age population by telemedical examination. 13.47% of the workers examined showed ocular findings necessitating treatment or control by an ophthalmologist, including ocular hypertension (5.7%), hypertensive retinopathy with loss of temporal retinal nerve fiber thickness (2.3%), epiretinal membrane (1.07%), glaucoma (0.97%), age-related macular degeneration and adult vitelliform maculopathy (0.53%), and diabetic retinopathy (0.2%). Two of the examined persons presented ocular findings requiring urgent treatment to prevent serious vision loss. Conclusion Using a telemedical approach, we collected epidemiological information about prevalence of eye diseases in the working-age population. Virtual eye clinics in occupational preventive medicine are a useful method to improve sight and reduce vision loss of workers by reducing travel time and inconvenience associated with an in-person appointment with an ophthalmologist. Keywords Teleophthalmology . Occupational medicine . OCT scan . IOP . RNFL Introduction Epidemiological data of eye diseases in healthy subjects is rare in Germany. Due to improvements in health care, new diagnostic and treatment approaches, and demographical changes The present work was performed in fulfillment of the requirements for obtaining the degree of “Dr. med. dent.”. * Elisabeth Grau [email protected] 1 Interdisciplinary Center for Preventive Medicine, Department of Ophthalmology, Friedrich-Alexander University, Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany 2 European Prevention Center, Luise-Rainer-Straße 6-10, 40235 Düsseldorf, Germany 3 Talkingeyes&More GmbH, Henkestraße 91, 91052 Erlangen, Germany over the last two decades, there is a great need for epidemiological data to plan future ophthalmic care [1]. While cataract was the number one cause for blindness worldwide in 1990 as well as in 2010, the prevalence of macular degeneration has risen to be the number one cause of blindness in high-income countries in 2010 [2, 3]. One problem faced in epidemiological ophthalmology research is the fact that most common eye diseases remain asymptomatic until late stage in the disease course. This consequently makes it necessary to determine the prevalence of eye diseases in asymptomatic, healthy cohorts. Since the benefit of early detection and prevention in ophthalmic care has often been discussed in public, this kind of data is crucial to determine the cost benefit ratio of preventive measures in occupational medicine. In the Waterloo Eye Study held in Canada, Irving et al. [4] found a prevalence of 16% for new critical diagnoses in asymptomatic patients presenting for routine eye examinations excluding patients needing spectacle prescription changes. Additionally, they found that with greater assessment Graefes Arch Clin Exp Ophthalmol intervals, the incidence of new diagnoses increased as well as with rising age. Another study held in the same department in 2003 had a comparable outcome. They showed that, depending on the diagnosis, between 41 and 50% of patients were unaware that they even had an ocular problem [5]. Another study from the University of Montréal, Canada, examined the prevalence of unknown ocular conditions in patients with refractive-based symptoms and found a prevalence of 26.1% for asymptomatic ocular conditions [6]. The Gutenberg Health Study is a large single-center study held in Mainz, Germany, and investigates prevalence, incidence, and risk factors of different eye diseases in a representative German population-based cohort [7–12]. Our research contributes to the epidemiological data collected in those studies. The tendency to establish medical care centers and joint practices with most of them located in metropolitan areas versus traditional doctor’s offices with one physician already is a problem in rural areas. Between 2000 and 2010, the number of individual ophthalmologic doctor’s offices dropped by almost 25% while the number of joint offices and medical care centers has been on the rise in Germany [1]. This issue is not unique to ophthalmology but has become an issue across all medical fields in Germany. To address this issue, telemedicine has gained recognition over the past years, but the technology required for implementing telemedicine has been lacking [13]. The costeffectiveness of teleophthalmology has been examined in various studies providing evidence that a telemedical screening for chronic eye diseases such as diabetic retinopathy, glaucoma, and macular degeneration is an economic approach [14]. Besides the benefit of teleophthalmology in areas which are medically undersupplied, occupational medicine is a field in which teleophthalmology may play a role prospectively. The World Federation of Occupational Therapists has given a statement on telehealth in occupational medicine, assessing it as an appropriate method of medical service in occupational medicine [15]. So far, teleophthalmology is not much employed in German occupational medicine but the benefit of telemedical methods in occupational medicine has been shown in other medical disciplines, especially dermatology and rehabilitation [16–18]. Fig. 1 The process of a telemedical examination from the worker at the examination site to the ophthalmologist working at a remote location Since results from other disciplines cannot simply be transferred to ophthalmology it is clear that there is a need for studies on the benefit of telemedicine in occupational ophthalmology. The aim of this study is to examine the prevalence of different eye diseases using a telemedical store-and-forward approach to gather information about the occurrence of common eye diseases in a group of the working-age population, who may benefit from further treatment to prevent disease progression. Methods This descriptive study was held as part of an occupational medical examination on a group of employees from a large company in Bavaria. The background of this study was the examination of 1002 employees by a mobile mini clinic including OCT-scanning and non-contact IOP-measuring, in addition to obtaining medical history, measuring blood pressure and taking blood samples. The evaluation of the collected data was performed by an experienced ophthalmologist (G.M.). Thus, we were able to provide high-end ophthalmic care in an occupational medical setting, using a telemedical approach. Mini clinic Medical history was taken by an electronic questionnaire, blood samples were taken, and blood pressure was measured at the examination site. No pupil dilatation was used for the ophthalmic examination. Optical coherence tomography (Spectralis SD-OCT, Heidelberg Engineering) was performed by a medical technician at the examination site. The intraocular pressure was measured non-invasively (Non-Contact Tonometer NT530/510, Nidek Co., LTD) just after the OCTexamination. Participants in our study have been examined by a telemedical approach. The process of a telemedical examination as performed in our study is shown in Fig. 1. The telemedical application used for the storage and transfer of patient data is called MedStage® which consists of a cloudbased electronic patient chart. The complete patient data was Graefes Arch Clin Exp Ophthalmol transferred to and stored in MedStage® for the remote collection of ocular data to enable it to be viewed by eye specialists for diagnosis in remote locations. MedStage® has been developed by the Talkingeyes&More GmbH and the TeleOphthalmology Institute Erlangen and was certified as medical product class IIa by TÜV Rheinland in 2018. The examination of the macula and the optic nerve head was performed by OCT. OCT images were uploaded in the cloud-based patient chart. The set of images consisted of vertical and horizontal line of the macula, circular scan of the optic nerve head, multicolor images of the macula, and images of morphological unexpectancies. The collected data and images were then sent using the secure hypertext transfer protocol (https) from the tablet/laptop to the Talkingeyes® Collaboration Network patient record system, from where a specialist consultant evaluated and diagnosed retinal images. The data and images were evaluated within 2 days after examination telemedically by an experienced ophthalmologist (G.M.). The medical reports were accessible by the participants within a patient portal of MedStage using personalized login data. The examination setting at the mini clinic is shown in Fig. 2. aircraft parts. All medical records were reviewed. Participants with incomplete data or missing examination results were excluded from statistical evaluation. The remaining 931 persons were included in the study. Both eyes were teleophthalmologically examined and separately evaluated by an experienced ophthalmologist (G.M.). The evaluated prevalences refer to participants, meaning there was a positive finding for the right and/or left eye. The cohort comprised 815 men and 116 women from 39 to 65 years of age. For the diagnosis of ocular hypertension, we used a cut-off point of 21 mmHg for the diagnosis of ocular hypertension as determined in previous studies [19]. Glaucoma was defined by a diffuse or localized thinning of the RNFL. This definition we used was previously used in studies before, according to the diagnostic criteria described by Jonas et al. [20]. We defined arterial hypertensive retinopathy with loss of temporal retinal nerve fiber layer thickness when we found arteriovenous crossings according to the classification system of KeithWagener-Barker [21–23] and a decreased temporal RNFL thickness lower than temporal RNFL thickness minus one standard deviation in hypertensive patients. Statistical methods Statistical analysis was performed using the SPSS version 21.0 for Windows Computer software package (SPSS Inc., Chicago, IL, USA). Descriptive studies about the cohort included analyses of frequencies, percentages, mean, and standard deviations. Results N = 931 persons were included in the statistical evaluation. The mean age of the entire cohort was 49.9 years (SD 6.70). The mean IOP of the right eye was 15.8 mmHg (SD 3.28), and the mean IOP of the left eye was 15.6 mmHg (SD 3.09). Study participants Ocular findings One thousand two workers were examined at the site of the company. The participation in the study was voluntary; all participants who signed up were examined without any selection or exclusion. The participants work as engineers and skilled workers at a company developing and producing Intraocular pressure The distribution of the mean intraocular pressure separated by age and gender is shown in Table 1. Fig. 2 Ophthalmic examination at the mini clinic and OCT-Scan (Spectralis SD-OCT, Heidelberg Engineering) Graefes Arch Clin Exp Ophthalmol Table 1 The table shows the distribution of age and the mean intraocular pressure (IOP) for the cohort separated by age and gender n Age M(SD)a IOP left eye M(SD)a IOP right eye M(SD)a Total 931 49.9 (6.70) 15.8 (3.28) 15.6 (3.09) Male Male < 50 815 410 49.9 (6.79) 44.2 (3.15) 15.6 (3.32) 15.8 (3.30) 15.5 (3.11) 15.4 (2.95) Male > 50 Female 405 116 55.7 (3.98) 49.5 (6.06) 15.9 (3.327) 15.7 (3.04) 15.7 (3.26) 15.8 (2.94) Female < 50 58 44.3 (2.91) 15.6 (3.12) 15.9 (2.99) Female > 50 58 54.8 (3.07) 15.8 (2.98) 15.6 (2.91) a M and SD represent mean and standard deviation (IOP in mmHg) Retinal nerve fiber layer thickness Ocular hypertension The mean global RNFL was 95.37 μm (SD 11.672). The mean RNFL in the nasal superior quadrant was 103.4 μm (SD 23.407), nasal 68.61 μm (SD 19.635), nasal inferior 105.09 μm (SD 24.105), temporal inferior 139.79 μm (SD 20.640), temporal 70.57 μm (SD 13.253), and temporal superior 136.32 μm (SD 20.575). Table 2 shows the measured values for the mean global, temporal superior, temporal, temporal inferior, nasal inferior, nasal, and nasal superior retinal nerve fiber layer thickness (RNFL) separated by age and gender. The thickness of the RNFL did not follow normal distribution. Ocular hypertension (IOP of 21 mmHg or greater) was found in 5.7% (N = 53) of all individuals with a prevalence of 5.1% (N = 21) in men under 50, 6.4% (N = 26) in men over 50, 1.7% (N = 1) in women under 50, and 8.6% (N = 5) in women over 50. 1.4% (N = 13) of all participants showed values above 25 mmHg. The values for intraocular pressure did not follow normal distribution. Pathologic ocular findings In total, we found a prevalence of 13.47% of pathologic ocular findings including the following diseases: ocular hypertension, arterial hypertensive retinopathy with loss of temporal retinal nerve fiber layer thickness, diabetic retinopathy, epiretinal membrane, macular drusen, agerelated macular degeneration, cystoid maculopathy, adult vitelliform maculopathy, glaucoma, retinal detachment, and choroidal nevi. OCT-findings Table 3 shows the distribution of OCT-findings separated by age and gender. We defined arterial hypertensive retinopathy with loss of temporal retinal nerve fiber layer thickness when we found arteriovenous crossings and a decreased temporal RNFL thickness lower than temporal RNFL thickness minus one standard deviation in hypertensive patients. The critical value was 59.0 μm for the right eye and 55.7 μm for the left eye. Using this definition, we found an arterial hypertensive retinopathy with loss of temporal retinal nerve fiber layer thickness in 2.3% (N = 21) of the study participants. Pathological OCT-findings of the macula including epiretinal membrane, macular drusen, age-related macular Table 2 Distribution of the mean global and nasal superior, nasal, nasal inferior, temporal inferior, temporal, and temporal superior RNFL separated by age and gender Total Male total Female total Male < 50 Male > 50 Female < 50 Female > 50 a n (probands/ eyes) RNFL global M(SD)a RNFL nasal superior M(SD)a RNFL nasal M(SD)a RNFL nasal inferior M(SD)a RNFL temporal inferior M(SD)a RNFL temporal M(SD)a RNFL temporal superior M(SD)a 931/1862 815/1630 116/232 410/820 405/810 58/116 58/116 95.37 (11.672) 95.23 (11.71) 96.31 (11.379) 96.26 (10.572) 94.2 (12.682) 97.24 (11.473) 95.39 (11.257) 103.4 (23.407) 103.92 (23.263) 99.75 (24.129) 106.39 (22.305) 101.42 (23.95) 99.84 (26.064) 99.66 (22.138) 68.61 (19.635) 68.57 (19.665) 68.88 (19.615) 69.69 (16.295) 67.44 (22.523) 69.06 (22.435) 68.7 (16.414) 105.09 (24.105) 104.55 (23.972) 108.87 (24.03) 107.15 (23.557) 101.91 (24.114) 110.37 (23.059) 107.38 (24.972) 139.79 (20.640) 139.19 (20.479) 144.06 (21.298) 140.1 (19.547) 138.26 (21.353) 145.53 (21.701) 142.6 (20.88) 70.57 (13.253) 70.36 (13.183) 72.05 (13.673) 69.63 (11.464) 71.1 (14.91) 72.75 (14.668) 71.34 (12.625) 136.32 (20.575) 136.38 (20.582) 135.89 (20.562) 137.73 (19.421) 135.02 (21.622) 138.69 (19.815) 133.09 (20.996) M and SD represent mean and standard deviation in micrometers Graefes Arch Clin Exp Ophthalmol Table 3 Distribution of OCT-findings by age group and gender Total Mean age Male Female Male < 50 Male > 50 Female < 50 Female > 50 Arterial hypertensive neuropathy %(n) Epiretinal gliosis %(n) Macular drusen %(n) 2.3 (21) 50.8 (SD 7.06) 2.45 (20) 0.9 (1) 2.4 (10) 2.5 (10) 1.7 (1) 0 (0) 1.07 (10) 52.7 (SD 6.90) 1.00 (8) 1.72 (2) 0.98 (4) 0.99 (4) 0 (0) 3.45 (2) 0.85 (8) 51.3 (SD 6.90) 1.00 (8) 0 (0) 0.98 (4) 0.99 (4) 0 (0) 0 (0) AMD and adult vitelliform maculopathy %(n) Glaucoma %(n) Diabetic retinopathy %(n) Cystoid maculopathy %(n) Choroidal nevus %(n) 0.53 (5) 55.2(SD 5.19) 0.49 (4) 0.86 (1) 0 (0) 0.99 (4) 0 (0) 1.7 (1) 0.97 (9) 0.2 (2) 51.7 (SD 7.26) 54.5 (SD 4.95) 1.1 (9) 0.1 (1) 0 (0) 0.9 (1) 0.7 (3) 0 (0) 1.5 (6) 0.2 (1) 0 (0) 0 (0) 0 (0) 1.7 (1) 0.2 (2) 60.0 (SD 5.0) 0.24 (2) 0 (0) 0 (0) 0.99 (2) 0 (0) 0 (0) 0.1 (1) 58 0.1 (1) 0 (0) 0 (0) 0.2 (1) 0 (0) 0 (0) degeneration, and adult vitelliform maculopathy were found with a prevalence of 3.9% (N = 36), 2.2% (N = 9) in men under 50, 5.9% (N = 24) in men, and 5.2% (N = 3) in women over 50. In women younger than 50 years, no case of macular degeneration was found. Glaucoma was found with a prevalence of 0.97% (N = 9). Only in three of the nine cases, glaucomatous optic atrophy was accompanied by an IOP of 21 mmHg or greater. One of those patients had an IOP of over 25 mmHg. Diabetic retinopathy defined as existence of retinal microaneurysms in multicolor images was found in two cases (prevalence 0.2%). Both of the findings were nonproliferative. Cystoid maculopathy was found with a prevalence of 0.2% (N = 2). 0.1% (N = 1) presented a choroidal nevus. Acute ocular diseases In two cases, we found serious eye conditions needing urgent treatment. One case (0.1%) presented an IOP of over 25 mmHg with glaucomatous nerve atrophy, and in one case (0.1%), we found retinal detachment. either if the participant had indicated a history of those or if it was indicated by blood samples. The blood markers used were a HbA1c of 6.5% or greater for Diabetes and a total cholesterol of 190 mg/dl or higher for hypercholesterinemia. The mean total cholesterol of the entire group was 209.7 mg/dl (SD 38.5). Discussion Using telemedical examination, our data shows a high prevalence of eye diseases among a working population. 13.47% of workers examined showed ocular findings requiring treatment or control by an ophthalmologist. Their ability to work was regarded as an indication that the persons included are relatively healthy. No participant made an indication of an existing eye disease in the medical history. The participation in the examination was voluntary which may have led to biased data. Since no selection or exclusion was performed, the fields of the workers’ activities are diverse. It is possible that workers Table 4 Systemic findings and risk factors found in the entire cohort (N = 931) Systemic findings Total group Table 4 shows the number and percentages of systemic findings and systemic risk factors of the total group (N = 931). For the statistical analysis, arterial hypertension was considered if the participant had made an indication in medical history and/or if the systolic blood pressure measured at the examination site was 140 mmHg or higher. By this definition, 44.8% (N = 417) of all participants suffered from arterial hypertension. Diabetes and hypercholesterinemia were counted as risk factors History of hypertension RR systolic > 140 mmHg RR diastolic > 90 mmHg Heart infarction Stroke History of diabetes HbA1c > 6.5% History of hypercholesterinemia Total cholesterol > 190 mg/dl Smoking n % 198 312 191 5 0 24 12 30 657 125 21.3 33.5 20.5 0.5 0 2.6 1.3 3.2 70.6 13.4 Graefes Arch Clin Exp Ophthalmol avoided an examination due to fear of finding a possible visual disability or, conversely, they may have been more likely to enroll because of concerns about their vision. All medical findings and data were handled confidentially. Only the medical staff could access the patient chart, and medical reports were available to the participants using personalized login data. There is great unawareness of eye diseases [24, 25]. To our knowledge, this is the first epidemiological ophthalmic study using OCT-scanning and non-contact intraocular pressure measurement. Therefore, our results can only be compared to studies using different approaches. In the Waterloo Eye Study [4], ocular findings in asymptomatic patients were found with a prevalence of 16%. The prevalence of asymptomatic and previously unknown eye diseases has been found to be 14% in a study held by Robinson et al. in Canada [5]. None of the authors distinguishes between critical findings in general and findings requiring urgent treatment to prevent vision loss. Since different methods were used, the numbers can only roughly be compared. Irving et al. do not break down the prevalences of different diagnoses but Robinson et al. reported an especially high number of cataract included in the 16% of asymptomatic eye diseases found, which was not assessed in our study. The occurrence of systemic risk factors, e.g., hypertension (8.94%), was described much lower by Robinson et al. compared to our study though the data they used relied on patients’ self-reports which probably led to the lower prevalence. In contrast to our study, the participants in both studies ranged from ages under 10 up to over 65 [4], or to over 85, respectively [5]. In a primary care clinic population, the prevalence of clinically important eye diseases was found to be 50.6% [26], pointing out the importance of regular eye examinations in patients with systemic risk factors. In consideration of demographical changes and a higher occurrence of patients with pre-existing conditions, the incidence of serious eye diseases will increasingly be an issue in the future. The diagnosis ocular hypertension (IOP >/= 21 mmHg) was found in 5.7% of all participants. Using a cut-off point of 21 mmHg for the diagnosis of ocular hypertension was chosen according to previous studies [19, 27]. In the Blue Montains Eye Study, a prevalence of 3.7% was found for ocular hypertension without matching disc and field changes; in the Los Angeles Latino Study, the prevalence was found to be 3.56%. Our diagnosis of ocular hypertension did not exclude participants presenting glaucomatous changes though only three of the nine participants diagnosed with glaucoma also presented an IOP >/= 21 mmHg. Also, we used the method of non-contact tonometry while in the Blue Mountains Eye Study, a Goldmann applanation tonometer was used for examination which might have led to higher measurements of the IOP in our study though contradictive studies have been published concerning this matter [28–30]. We found a mean IOP of the right eye of 15.8 mmHg (SD 3.28) and a mean IOP of the left eye of 15.6 mmHg (SD 3.09). Compared to other white population-based studies, the mean IOP in our study was similar or slightly higher [7, 31–33] which might again be due to different measurement techniques. We reported a mean global retinal nerve fiber layer thickness of 95.37 μm. Our data were similar to a recent study held by a group in Mainz, Germany, where they found a mean global RNFL of 96.0 μm (SD 10.3) [8]. They also found that the RNFL thickness was thickest in the temporal inferior sector, followed by the temporal superior sector, the nasal inferior sector, the nasal superior sector, the temporal sector, and the nasal sector. Our study confirms these results. Other studies had comparable outcomes with similar or slightly thinner RNFL thickness [34–37]. The prevalence of hypertensive retinopathy with loss of temporal retinal nerve fiber layer thickness was 2.3%. The usage of arteriovenous crossings as a diagnostic sign was according to previously published studies, in which arteriovenous crossings have been classified as a sign for hypertensive retinopathy according to the classification system of Keith-Wagener-Barker [21–23]. We have selected patients with signs of hypertensive retinopathy and a reduction in the temporal retinal nerve fiber layer thickness. Since arterial hypertension was a mandatory condition in our study for the diagnosis of hypertensive retinopathy, we are not able to address what the prevalence of retinal vascular changes in normotensive patients would be. However, it has been reported that even in patients with normal blood pressure, vascular changes typical for hypertensive retinopathy have been observed [38]. The prevalence of epiretinal membrane in our study was 1.07% and has in other studies been found to range from 0.5 to 28.9% with differences of prevalence depending on ethnicity and age group of the population examined [39–42]. In the Blue Mountains Eye Study, a prevalence of 1.9% in people under the age of 60 and 7.2% in people between 60 and 69 was found [43], demonstrating increasing prevalence with increasing age. In the Beaver Dam Eye Study, the prevalence in people from 43 to 54 years of age was 2.7% and increased up to 12.8% in the age group over 75 [44]. The prevalence of AMD and adult vitelliform maculopathy was in our study 0.53%. Considering the fact that the mean age in our study was 49.9 years (SD 6.79) with the oldest participant at 65 years, the results are not different from other studies which have shown a strong association of age and AMD [45]. We found macular drusen with a prevalence of 0.85%. Macular drusen as an early stage of AMD also have been found to be strongly associated with age [46]. Since the maximum age in our group was 65, this might explain the low prevalence. We found a prevalence of 0.97% for glaucoma. The definition we used was used in previously published studies, according to the diagnostic criteria described by Jonas et al. [20, 47–49]. Glaucoma has been estimated to occur with a prevalence of 3.54% worldwide [50] and 1.44% or 2.32% in Germany [9, 51]. A study held in Germany between 2002 and 2004 showed a strong association between age and glaucomatous optic Graefes Arch Clin Exp Ophthalmol atrophy with prevalences from 0.07% in the age group 45–49 up to 0.82% in the age group from 60 to 64 [52]. Age is clearly a risk factor for the development of glaucoma, although there have been reported cases in patients under the age of 40, so it should not only be regarded as a problem of the aging society [12]. Since epidemiological data in healthy subjects are rare, this study reports valuable data showing that the prevalence of eye diseases is high in the average working population. In German occupational medicine, a morphological examination of the eye is not mandatory but in cases of computer work it has to be offered by the employer. The need for “virtual eye clinics” in occupational preventive medicine to allow teleophthalmology has been clear for many years, but the technology required to deliver them has previously been lacking. The aim of occupational teleophthalmology is to ensure ocular health and good vision at workplaces, mainly assessing retinal morphology and preventing existing eye diseases with the advantages of a telemedical approach. Our scientific research in this field provided useful arguments and further evidence that preventive teleophthalmology is beneficial for application by occupational physicians. The use of the software MedStage in peripheral working locations allowed decisionmaking by experienced teleophthalmic consultants of the Tele-Ophthalmology Institute Erlangen. This paper summarizes the applied telemedical technology, conducted in a big South German company, focusing on critical ocular morphological conditions, such as macular and retinal diseases. The knowledge obtained can be useful to guide proper preventive programs for eye care aimed at improving workers’ vision. Funding information No funding was received for this research. Compliance with ethical standards Conflict of interest Elisabeth Grau claims she has no conflict of interest. Folkert Horn claims he has no conflict of interest. Uwe Nixdorff claims he has no conflict of interest. Georg Michelson is the owner of the Talkingeyes&More GmbH, Erlangen, Germany. Ethical approval All procedures performed in studies involving human participants were in accordance with the ethical standards of the Universitätsklinikum Erlangen and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent Informed consent was obtained from all individual participants included in the study. References 1. 2. 3. 4. 5. 6. Conclusion 7. Our data suggest a high prevalence of eye diseases in a group representative for the working-age population by telemedical examination. 13.47% of workers examined showed ocular findings which should be treated or controlled by an ophthalmologist. 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