Automatic inference of ICD-10 codes from German ophthalmologic physicians' letters using natural language processing

Physicians' letters are the optimal source of diagnoses for registries. However, most registries demand for diagnosis codes such as ICD-10. We herein describe an algorithm that infers ICD-10 codes from German ophthalmologic physicians' letters. We assess the method in three German eye hospitals. Our algorithm is based on the nearest-neighbor method as well as on a large thesaurus for ICD-10 codes. This thesaurus was embedded into a Word2Vec space created from anonymized physicians' reports of the first hospital. For evaluation, each of the three hospitals sent all diagnoses taken from 100 letters. The inferred ICD-10 codes were evaluated for correctness by the senders. A total of 3332 natural language terms had been sent in (812 hospital one, 1473 hospital two, 1047 hospital three). A total of 526 non-diagnoses were excluded upfront. 2806 ICD-10 codes were inferred (771 hospital one, 1226 hospital two, 809 hospital three). In the first hospital, 98% were fully correct and 99% correct at the level of the superordinate disease concept. The percentages in hospital two were 69% and 86%. The respective numbers for hospital three were 69% and 91%. Our simple method is capable of inferring ICD-10 codes for German natural language diagnoses, especially when the embedding space has been built with physicians' letters from the same hospital. The method may yield sufficient accuracy for many tasks in the multi-centric setting and can easily be adapted to other languages/specialities.

Light conditions influence optic nerve OCT angiography parameter in healthy subjects with neutral pupils

Optical coherence tomography angiography measurements are influenced by a range of environmental factors as blood pressure and physical fitness. The present study aimed to evaluate the effects of light and dark exposure in eyes with neutral and mydriatic pupils on vessel density in the macular and optic nerve head regions, as measured using optical coherence tomography angiography (OCTA). 55 eyes of 55 healthy volunteers (28 patients with neutral pupils; 27.18 ± 4.33 years) were examined using a high-speed and high-resolution spectral-domain OCT XR Avanti system with a split-spectrum amplitude de-correlation angiography algorithm. OCTA imaging was performed after dark adaptation and after exposure to light. The vessel density data of the superficial and deep retinal macular and optic nerve head region OCT-angiogram were analyzed for these two light conditions. Through Bonferroni correction for multiple testing, the p- value was adapted from 0.05 to 0.017. In eyes with neutral pupils, a significant increase was found in the capillary region of the optic nerve head region (p = 0.002), comparing dark- and light-adaptation. In the macular region of eyes with neutral (p = 0.718) and mydriatic pupils (p = 0.043), no significant differences were observed, as were any in the optic nerve head region of the mydriatic eyes (p = 0.797). This observation suggests that light conditions could be a possible factor influencing OCTA measurements. After dark exposure, vessel density data were significantly different between eyes with neutral and mydriatic pupils (nerve head region: p < 0.0001, superficial macula: p < 0.0001, deep macula: p = 0.0025). These data warn for the effect of mydriatic drops on vessel density measurements.

[Diagnostics of diseases of the optic nerve head in times of artificial intelligence and big data]

Hintergrund

Der Einsatz von künstlicher Intelligenz (KI) ist unter anderem in der automatischen Bildsegmentierung, -analyse und Klassifikation interessant und bereits für verschiedene Bereiche der Augenheilkunde beschrieben.

Fragestellung

Diese Arbeit soll einen Überblick über aktuelle Ansätze und Fortschritte bei der Anwendung von Big Data und KI bei verschiedenen Erkrankungen des Sehnervenkopfes geben.

Material und Methode

Es wurde eine PubMed-Recherche durchgeführt. Gesucht wurde nach Studien, die klinische Fragestellungen mithilfe von Big-Data-Ansätzen beantworteten oder klassische Methoden des maschinellen Lernens bei der Analyse von multimodaler Bildgebung des Sehnervenkopfes verwendeten.

Ergebnisse

Big Data kann bei Volkskrankheiten wie dem Glaukom helfen, klinische Fragestellungen zu beantworten. KI findet sowohl bei der Segmentierung von multimodaler Bildgebung des Sehnervenkopfes als auch bei der Klassifikation von Erkrankungen wie dem Glaukom oder der Stauungspapille auf diesen Bilddaten Anwendung.

Schlussfolgerung

Mithilfe von Big Data und KI können Zusammenhänge besser erkannt und die Diagnostik und Verlaufsbeurteilung von Erkrankungen des Sehnervenkopfes erleichtert oder automatisiert werden. Eine Voraussetzung für die klinische Anwendung ist in Europa die CE-Kennzeichnung als ein Medizinprodukt und in den USA die Zulassung durch die Food and Drug Administration.

["Flipped classroom"-A future concept for student teaching in ophthalmology?]

BACKGROUND

"Flipped classroom" is a didactic teaching concept in which learning contents are prepared by self-study with arranged tools before the classroom session. The concept offers the advantage of a uniform knowledge base for the students at the beginning of the course and also the advantage of a greater theoretical knowledge, which creates more opportunities for practical exercises, application and consolidation in the subsequent joint teaching units. This study describes the establishment and application of such a model in student teaching in ophthalmology and analyzes the student's evaluation.

METHODOLOGY

For the winter term 2018/2019, a new teaching module was designed and established in a cooperation between the department of ophthalmology and the Institute for Education and Study Affairs (IfAS) at the medical faculty of the University of Münster. A uniform training of the lecturers as well as a preparation of the students for the restructuring took place. After the course the evaluation of the students was recorded and evaluated using a standardized online evaluation.

RESULTS

Between the winter semester 2018/2019 and the winter semester 2019/2020, an average of 112.3 ± 4.0 students were taught with the "flipped classroom" model. Of these 93.7% were able to give an assessment. In the previous semesters with the old teaching concept (summer semester 2015 to summer semester 2018), the average number of students was 115.4 ± 15.1 with an assessment rate of 93.3%. The new teaching concept achieved on average a better assessment than the old module.

CONCLUSION

With a "flipped classroom" space and flexibility can be generated for a more individual course preparation and at the same time a higher practical part. Further studies are needed to analyze whether this also enables a sustainable transfer of knowledge.

Prospective PED-study of intravitreal aflibercept for refractory vascularized pigment epithelium detachment due to age-related macular degeneration: morphologic characteristics of non-responders in optical coherence tomography

Purpose

The aim of this study was to investigate the outcomes of a fixed intravitreal aflibercept regimen in patients with vascular pigment epithelium detachment (vPED) secondary to age-related macular degeneration with refractory subretinal fluid.

Methods

A prospective, interventional case series involved 20 eyes of 20 patients with refractory subretinal fluid and vPED treated with at least three injections of intravitreal anti-VEGF prior to study inclusion. After study inclusion, patients were treated with three injections of intravitreal aflibercept 2 mg/0.05 mL monthly followed by injections every 8 weeks. Best-corrected visual acuity (BCVA) and spectral-domain optical coherence tomography (SD-OCT) were evaluated at all visits. Fluorescein angiography and indocyanine green angiography were performed at baseline and quarterly. Primary outcomes were effectivity of a fixed treatment as measured in change in BCVA, PED greatest linear diameter (GLD), and PED height from baseline to month 12. In an additional post hoc analysis, vPED patients were differentiated into two groups: (1) vPED lesions that showed persistence of subretinal fluid throughout 1 year of treatment and (2) vPED lesions that showed complete resolution of subretinal fluid at least at one of the monthly performed OCT volume scans. Reflectivity values were determined in the subretinal pigment epithelium (RPE) compartment in OCT scans at baseline, month 6 and 12.

Results

A total of 18 patients completed the study protocol. The mean age was 74.8 ± 10.6 years, and six patients were female. The median BCVA of all patients was 72.0 ± 8.0 EDTRS letters at baseline and 72.5 ± 9.5 EDTRS letters at 12-month follow-up (p = 0.7420). The median PED height in all patients as measured in the OCT images significantly decreased from 372.0 ± 140.0 μm to 149.0 ± 142.0 μm after 12 months of treatment (p = 0.0020). Persistent subretinal fluid was present at every OCT control in six patients (group 1). Twelve patients showed resolution of subretinal fluid at least at one OCT control (group 2). Reflectivity values in the sub-RPE compartment in OCT scans were 41.48 ± 4.48 (group 1) and 42.62 ± 12.34 (group 2) at baseline (p = 0.854) and 65.88 ± 6.74 and 50.87 ± 14.11 at month 12 (p = 0.038).

Conclusions

Intravitreal aflibercept in refractory vPED leads to a significant reduction in PED height and disease activity as well as preservation of BCVA over 1 year. Persistent subretinal fluid was present in PED lesions with high values of reflectivity under the RPE, suggesting both a diffusion barrier and an increasing fibrovascular maturization of the choroidal neovascularization.

Trial registration

ClinicalTrials.gov Identifier: NCT03370380

Impact of integrated multiple image averaging on OCT angiography image quality and quantitative parameters

PURPOSE

Multiple image averaging (MIA) is a new approach to improve OCT angiography (OCTA) imaging. The aim of this work was to analyze the impact of MIA on image quality and quantitative OCTA parameters.

METHODS

Twenty eyes from 20 healthy volunteers (55.65 ± 14.8 years) were prospectively enrolled. Imaging was performed using two commercially available OCTA devices (Canon OCT HS-100, Optovue AngioVue) using a uniform imaging protocol. Each participant had two single scans of the macula (3 × 3mm, Canon and Optovue) as well as five continuous single scan imaging procedures (3 × 3mm each) using the Canon device. Three out of five of these images with highest quality were manually chosen and then automatically processed by the Canon device using MIA. The superficial retinal plexus of the single scans and of MIA images was analyzed with regard to the device' own image quality scores (IQS), peak signal-to-noise ratio (PSNR), the size of the foveolar avascular zone (FAZ), and vessel density (VD). Image acquisition times were recorded. Parameters were compared between the devices and the different imaging protocols.

RESULTS

Average acquisition time was significantly higher for the MIA compared with the single measurements (29.09 ± 10.19 seconds (s) (MIA) vs. 5.56 ± 2.17 s (Canon single scan) vs. 20.28 ± 6.81 s (Optovue) (p < 0.001)). IQS showed no significant differences between the devices and between the recording protocols. PSNR was 12.38 ± 0.20 (Canon single scan), 13.01 ± 0.36 (Canon MIA), and 14.34 ± 0.60 (Optovue) (p < 0.001 between the groups). Mean FAZ area in Canon single scans was 0.29 ± 0.06 mm², 0.27 ± 0.07 mm² using MIA, and 0.27 ± 0.08 mm² using the Optovue device. There was no significant difference between mean FAZ measurements before and after averaging (Canon single scan vs. MIA, p = 0.168). VD of the parafoveal area using MIA was significantly lower compared with both single scans (p < 0.001).

CONCLUSIONS

MIA can improve PSNR, but it also reduces imaging speed and significantly affects VD measurements. Therefore, when comparing OCTA data, the use of uniform imaging protocols is required.

[Spontaneous intraocular hemorrhage under oral anticoagulation : Apixaban in comparison to phenprocoumon]

BACKGROUND

To determine and compare the frequency of intraocular hemorrhage in patients who underwent oral anticoagulation with apixaban or phenprocoumon.

METHODS

A retrospective analysis of patients under oral anticoagulant medication (apixaban or phenprocoumon) seen between January 2015 and June 2015 at the department of ophthalmology, University of Muenster Medical Center was performed. Vitreal or retinal hemorrhage in addition to clinical information including age, gender, best corrected visual acuity, concomitant diseases, concomitant medication and therapy were obtained. Bleeding frequency in both groups was compared using Fisher's exact test.

RESULTS

A total of 172 patients were included with a mean age = 74.0 ± 10.6 years, 57.0% (n = 98) male and 43.0% (n = 74) female. In the phenprocoumon group 147 patients (3.4%, n = 5) developed a retinal or vitreal hemorrhage. In the apxiban group 25 patients (36%, n = 9) developed a retinal or vitreal hemorrhage. There was a significant correlation between the group and bleeding risk (p < 0.001).

CONCLUSION

There was a significant correlation between medication (apixaban vs. phenprocoumon) and bleeding risk in this study population. Further studies with more patients especially in patients with a high risk of hemorhage, age-related macular degeneration (AMD) and proliferative diabetic retinopathy are needed.

[Flow density measurements using optical coherence tomography angiography : Impact of age and gender]

BACKGROUND

This article presents the normative data for flow density measured using optical coherence tomography (OCT) angiography and the impact of age and gender is evaluated.

METHODS

In this study 58 eyes from 58 healthy volunteers with no history of any ocular disease or ocular surgery were included. The OCT angiography imaging was performed using the RTVue XR Avanti with the AngioVue (Optovue, Fremont, CA). The macula was imaged using a 3 × 3 mm scan, and the flow density data in the superficial retinal OCT angiogram and deep retinal OCT angiogram were extracted and analyzed. The groups were compared using the Mann-Whitney U‑test and the degree of correlation between two variables was expressed as the Spearman's correlation coefficient (rSp.) RESULTS: The mean subject age was 38.3 ± 14.6 years. The flow density (whole en face) in the deep retinal OCT angiogram was significantly higher compared to the flow density in the superficial retinal OCT angiogram (p < 0.001). There was no significant difference in the mean flow density in superficial and deep OCT angiograms of the macula between males (n = 27) and females (n = 31). There was a significant correlation between the flow density in the deep retinal OCT angiogram and age (rSp. = -0.41, p = 0.001).

CONCLUSION

Whereas gender has no impact on the flow density measured using OCT angiography, there was a significant correlation between the flow density in the deep retinal OCT angiogram and age.

[Optical coherence tomography angiography: Value for glaucoma diagnostics]

BACKGROUND

Optical coherence tomography angiography (OCTA) is a novel noninvasive method which enables a quantitative evaluation of retinal and optic nerve head (ONH) perfusion. In this article, we discuss the principles of the application of OCTA and give a summary of the knowledge gained by using this method in glaucoma patients.

METHODS

This article is based on a selective literature search and the analysis of own data.

RESULTS

Quantitative OCTA parameters have a good reproducibility in glaucoma patients. Glaucoma patients show a reduced flow density (FD) in the ONH and in the area of the macula compared with a healthy control group. The FD parameters show a good diagnostic discriminatory power but are not superior to the structural parameters used in routine diagnostics. The reduced FD measured using OCTA correlates with the extent of functional and structural glaucoma damage.

CONCLUSION

The OCTA is noninvasive, fast and reproducible. Initial results from studies on glaucoma patients show the high diagnostic potential of this method. The OCTA could become a part of clinical glaucoma management in the future.

Signal reduction in choriocapillaris and segmentation errors in spectral domain OCT angiography caused by soft drusen

PURPOSE

To analyze signal reduction in choriocapillaris (CC) and segmentation errors in spectral domain optical coherence tomography angiography (OCT-A) caused by soft drusen due to age-related macular degeneration (AMD).

METHODS

Twenty-four eyes of 24 patients underwent multimodal retinal imaging including central 3 × 3mm² OCT-A (AngioVue, Optovue). Three drusen per study eye were randomly chosen and evaluated regarding drusen height, diameter, and accuracy of OCT-A layer segmentation in lesion proximity. Structural en-face OCT CC images were graded qualitatively and quantitatively regarding signal loss underneath the individual drusen area. Those drusen that showed no distinct signal loss in structural en-face OCT CC images were further evaluated in OCT-A. CC decorrelation signal index was measured within a 30-μm OCT-A CC slab in the exact area of drusen affection. Data were compared to healthy age-matched control subjects. Accuracy of layer segmentation, OCT CC data, and OCT-A CC data were correlated to morphological drusen parameters.

RESULTS

Mean drusen height and diameter were 91.57 ± 19.5μm and 315.17 ± 116.7μm. OCT-A layer segmentation of the inner plexiform layer (IPL) was disturbed by more than 50 μm in proximity to 26 drusen (36.1%). In these patients, drusen height was significantly higher compared to those with accurate IPL segmentation (p = 0.0126). Sixty-six out of 72 drusen (91.7%) caused a distinct signal loss in the structural en-face OCT CC image. Drusen height and drusen diameter were significantly higher in this group compared to the six drusen with a sufficient signal (p = 0.0276, p = 0.0025). CC decorrelation signal index measured in the area of these six drusen without OCT signal loss (8.3%) was reduced compared to age-matched healthy controls (73.6 vs. 100.1; p = 0.001).

CONCLUSIONS

Signal attenuation in CC slabs and segmentation errors of the IPL depend on drusen morphology. Both are frequent artifacts in OCT-A imaging in patients with soft drusen and must be considered during image analysis.

[Contact lens-associated Paecilomyces lilacinus keratitis]

We present the case of a 23-year-old otherwise healthy female patient with contact lens-associated Paecilomyces lilacinus keratitis. The clinical findings stabilized after initial local antimycotic and antibacterial treatment; however, in the further course of local therapy an extensive relapse occurred which required treatment by perforating keratoplasty à chaud due to a penetrating corneal ulcer. The patient responded well to subsequent treatment with systemic and local antimycotic medication. After a few months HLA-matched keratoplasty was performed. During the follow-up time of 14 months there were no signs of recurrence of the infection.

Impact of eye-tracking technology on OCT-angiography imaging quality in age-related macular degeneration

OBJECTIVE

To evaluate the impact of eye-tracking (ET) technology on optical coherence tomography angiography (OCT-A) image quality and manifestation of motion artifacts in patients with age-related macular degeneration (AMD).

METHODS

In a prospective trial, multimodal retinal imaging including OCT-A was performed in 30 patients (78.97 ± 9.7 years) affected by different stages of AMD. Central 3 × 3 mm² OCT-A imaging was performed four times consecutively in each patient, twice with active, and twice with inactive ET. Parameters for image evaluation were signal strength index (SSI), variability of foveal vessel density (VD), acquisition time, presence of motion artifacts caused by eye movement (blink lines, displacement) and by software correction of eye movement (quilting, stretch artifacts, vessel doubling). Images were evaluated by two independent readers with subsequent senior reader arbitration for presence of artifacts, and an OCT-A motion artifact score (MAS) was calculated.

RESULTS

Eight patients had early and eight patients had intermediate stages of AMD. Four patients had an atrophic late stage and ten patients an exudative stage of the disease. SSI was 53.55 with inactive and 57.18 with active ET (p = 0.0005). Coefficients of variability of VD between the first and second measurement were 8.9% with inactive and 5.7% with active ET. Mean image acquisition time was 15.97 s (active ET: 22.88 s, p < 0.001). Presence of motion artifacts was significantly higher with inactive ET (mean MAS 3.27 vs. 1.93; p < 0.0001). MAS correlated with AMD disease stage [p = 0.0031 (inactive ET) and p < 0.0001 (active ET)] and with SSI (p = 0.0072 and p = 0.0006).

CONCLUSIONS

In patients with AMD, active ET technology offers an improved image quality in OCT-A imaging regarding presence of motion artifacts at the expense of higher acquisition time.

[Implementation of electronic health records at a tertiary care eye hospital]

BACKGROUND

Although electronic health records (EHR) were introduced into ophthalmology practices many years ago, paper-based medical records are still common in most tertiary care eye hospitals.

MATERIAL AND METHODS

We report on the implementation of an EHR system at the university eye hospital in Münster in the time period between January and December 2013.

RESULTS

Advantages of an EHR system in the setting of a university eye hospital include ubiquitous access to patient data, structurability as well as scientific interpretability. Data safety, personnel and financial investment and integration into existing hospital software systems represent the main challenges.

CONCLUSION

The EHR system will replace paper-based records in the future. In view of the high need for visualization and recording of medical findings, EHR software solutions seem promising particularly in ophthalmology.

[Traumatic Lacrimal Duct Stenosis: Demographics and Success Rate of Surgical Procedures for Secondary Treatment]

BACKGROUND

Traumatic lacrimal duct stenosis can be the result of sharp trauma of the eyelid, indirect trauma or surgery in the nasoorbital region, as well as burns, chemotherapy and radiation of the facial region. The aim of the study is to present the demographics, patient satisfaction, and course of different surgical procedures for secondary treatment of traumatic lacrimal duct stenosis.

METHODS

We retrospectively reviewed the medical records of 50 patients who required surgery for traumatic lacrimal duct stenosis from 2009 to 2011 at the University Eye Hospital in Muenster. The evaluation included the following criteria: age, sex, duration of symptoms, complication rate and the rate of recurrence. We systematically evaluated the medical data and asked the patients about the recent symptoms via telephone questionnaire.

RESULTS

60 eyes of 50 patients were included (18 women; 32 men; age: 51.8 ± 17.1 years); 34 eyes (56.7 %) had already had operations of the lacrimal system. The success rate was 58.1 %. The mean postoperative follow-up was 52.3 ± 10.7 months. In 11 cases (18.3 %), a dakryocystorhinostomy (DCR) was necessary.

CONCLUSION

Traumatic lacrimal stenosis is more common in men, and has a poorer prognosis than lacrimal duct stenosis from other causes.

[Ease of handling of first and second generation rebound tonometers]

PURPOSE

To evaluate the ease of handling of two rebound tonometers, which are designed for self-measurement of intraocular pressure (IOP) in a clinical setting by untrained patients.

METHODS

After self-measurement of the IOP with the rebound tonometers iCare ONE and iCare HOME, participants were asked to complete a questionnaire containing different subitems concerning ease of operation using a visual analog scale (1 = very good to 5 = very poor). Moreover, the feasibility and duration of measurement were tested.

RESULTS

A total of 147 subjects participated in this study. The mean score for general handling ability was 2.79 ± 1.01 for the iCare ONE and 1.85 ± 0.87 for the iCare HOME (p < 0.001). The evaluation of the subitems sense of safety (iCare ONE: 2.71 ± 1.03 and iCare HOME: 1.87 ± 0.81, p < 0.001) and comfort of measurement (iCare ONE: 2.07 ± 1.01 and iCare HOME: 1.66 ± 0.72, p < 0.001) also showed a significant discrepancy between the two tonometers. Participants needed significantly less time for a single valid measurement when using the iCare HOME tonometer (mean 66.14 ± 61.54 s) compared to the iCare ONE tonometer (mean 81.54 ± 69.51 s, p < 0.001).

CONCLUSIONS

A better handling of the iCare HOME rebound tonometer in comparison to the iCare ONE tonometer can be deduced on the basis of the subjective assessments of patients and the shorter duration of measurements. Moreover, the iCare HOME received a significantly better evaluation for all subitems. The accuracy of measurements using the iCare HOME still needs to be clarified.

[Effect of Hypericin on the Function of the Neuroretina: An Electroretinographic Study]

BACKGROUND

Hypericin is an important component of the Saint John's wort (Hypericum perforatum). It is assumed to inhibit intracellular signalling cascades, which contribute to neoangiogenesis. The phototoxic effect of hypericin on the retina was investigated in human retinal pigment epithelium (RPE); hypericin induces oxidative stress and has also been described to be an inhibitor of Ca(2+) influx channel in cultured RPE cells. The aim of our study is to evaluate the effect of hypericine on the function of the neuroretina.

METHODS

Isolated bovine retinas were perfused with an oxygen saturated nutrient solution (1 mL/min). We exposed the retina to a flashlight of 6.3 mlx every 5 min. The electroretinogram (ERG) was recorded as a transretinal potential using Ag/AgCl electrodes. ERGs were monitored before, during and after hypericin exposure.

RESULTS

In three independent experiments we investigated the effect of hypericin on the amplitude of the b-wave. In our experiments we observed a significant reduction of the amplitude of the b-wave to 87.1 ± 3.5 % (p = 0.02). This reduction was in all our experiments partially reversible. After hypericin wash-out the b-wave amplitude did not recover completely and did not return to the initial value (91.0 ± 5.1 %; not significant). We did not observe a significant effect of hypericin on the implicit time of the b-wave.

CONCLUSION

This study shows for the first time that hypericin influences retinal signal transduction, suggesting that hypericin impairs not only the RPE, but also affects retinal signalling and function.

[Microsurgical Treatment of Canalicular Stenosis: Long-Term Follow-Up]

PURPOSE

Studies about the indication and the functional prognosis of microsurgical treatment of canalicular stenosis (CR) are rare. In this study we determined the cause, recurrence and success rates of CR and compared our results with the results in the literature.

METHODS

We retrospectively reviewed the medical records of 22 patients who required a microsurgical treatment of canalicular stenosis (CR) from 2009 to 2011. We systematically evaluated the medical data and asked the patients about the recent symptoms via telephone questionnaire.

RESULTS

22 patients were included (73 % women; 27 % men; age: 52.8 ± 19.9 years), 12 (55 %) patients had already had operations. The mean postoperative follow-up was 45 ± 9.2 months. The patients were followed for a minimum of 30 months. The success rate was 58 %.

CONCLUSION

In some cases like long localised canalicular stenosis and especially after traumatic lacerations of the lacrimal canaliculi, a microsurgical treatment of canalicular stenosis is required. The aim of this procedure is to restore the lacrimal mucosa continuity so that a spontaneous lacrimal drainage is possible. The success rate of CR in our study was 58 %.

Long-term outcomes of phakic patients with diabetic macular oedema treated with intravitreal fluocinolone acetonide (FAc) implants

PURPOSE

Diabetic macular oedema (DMO) is a leading cause of blindness in working-age adults. Slow-release, nonbioerodible fluocinolone acetonide (FAc) implants have shown efficacy in the treatment of DMO; however, the National Institute for Health and Care Excellence recommends that FAc should be used in patients with chronic DMO considered insufficiently responsive to other available therapies only if the eye to be treated is pseudophakic. The goal of this analysis was to examine treatment outcomes in phakic patients who received 0.2 μg/day FAc implant.

METHODS

This analysis of the phase 3 FAME (Fluocinolone Acetonide in Diabetic Macular Edema) data examines the safety and efficacy of FAc implants in patients who underwent cataract extraction before (cataract before implant (CBI) group) or after (cataract after implant (CAI) group) receiving the implant. The data were further examined by DMO duration.

RESULTS

Best corrected visual acuity (BCVA) after 36 months was comparable in the CAI and CBI groups. Both the percentage of patients gaining ≥ 3 lines of vision and mean change in BCVA letter score were numerically greater in the CAI group. In addition, most patients who underwent cataract surgery experienced a net gain in BCVA from presurgery baseline as well as from original study baseline.

CONCLUSIONS

These data support the use of 0.2 μg/day FAc implants in phakic as well as in pseudophakic patients. These findings will serve as a pilot for design of future studies to evaluate the potential protective effect of FAc implants before cataract surgery in patients with DMO and cataract.

[Rebound tonometry after vitreoretinal surgery]

PURPOSE

The aim of this study was to analyze the practicability and comparability of the Icare rebound tonometer (RT) versus the Schiötz indentation tonometer (SIT) and the Goldmann applanation tonometer (GAT) for measuring intraocular pressure (IOP) in patients after pars plana vitrectomy (PPV).

METHODS

A total of 100 eyes from 100 patients who underwent vitreoretinal surgery in the Department of Ophthalmology, University of Cologne were included in this prospective analysis. The IOP was measured using RT preoperatively, on the day of surgery and 2 days after surgery, using SIT on the day of surgery and GAT preoperatively and 2 days after surgery. For the evaluation eyes were divided into subgroups with respect to the endotamponade selected and the IOP level.

RESULTS

The mean preoperative IOP for all enrolled eyes was 15.4 ± 8.0 mmHg for RT and 16.1 ± 7.9 mmHg for GAT. Bland-Altman analysis revealed a bias between RT and GAT of - 0.6 mmHg. Bland-Altman analysis for the postoperative course of all eyes revealed a bias of 3.0 mmHg between RT and SIT on the day of surgery and no bias between RT and GAT in the further postoperative follow-up.

CONCLUSION

Rebound tonometry seems to provide precise IOP values after vitreoretinal surgery. Divergence from SIT values on the day of surgery is presumably due to a general tendency of SIT to underestimate IOP values. Therefore, RT can be used in the clinical routine after vitreoretinal surgery as an alternative to GAT.

[Diurnal Fluctuations of Intraocular Pressure, Blood Pressure, and Ocular Perfusion Pressure in Glaucoma Patients]

BACKGROUND

An elevated intraocular pressure remains the main risk factor for the development and progression of glaucoma but other factors such as fluctuations of the intraocular pressure, the blood pressure, and the ocular perfusion pressure are gaining in importance. The influence of the anti-glaucomatous therapies on these parameters is barely investigated. This study investigates 1) a correlation between the fluctuations of the intraocular pressure, the blood pressure and the ocular perfusion pressure with the severity of the glaucoma damage and 2) if these parameters can be influenced by different anti-glaucomatous therapies.

MATERIAL AND METHODS

Data from 121 glaucoma patients who had been hospitalised for 24-hour measurements of the intraocular pressure and blood pressure between 2003 and 2012 were analysed retrospectively. The patients were divided into groups by the severity of the glaucoma damage and by their anti-glaucomatous therapy. Mean values for the intraocular pressure, the blood pressure and the ocular perfusion pressure were calculated and correlated with the individual groups. The statistical analysis was performed with SPSS21.0 using Kruskal-Wallis and Mann-Whitney U tests for the comparison of the groups. RESULTS with p < 0.05 were considered statistically significant.

RESULTS

The severity of the glaucoma damage correlated significantly with higher mean values of the intraocular pressure and its fluctuations, as well as with a nocturnal decrease of the blood pressure and low mean values of the ocular perfusion pressure (p < 0.0001). The anti-glaucomatous therapy decreased the intraocular pressure to normal values. A monotherapy with carboanhydrase inhibitors correlated with the lowest fluctuations of the ocular perfusion pressure while a quadri-therapy was associated with higher values of the intraocular pressure and its fluctuations. The anti-glaucomatous therapy did not show an association with the blood pressure or the ocular perfusion pressure.

CONCLUSION

Glaucoma is negatively influenced by high intraocular pressure, nocturnal blood pressure decreases and ocular perfusion pressure fluctuations. A monotherapy with carboanhydrase inhibitors seems to be sufficient to decrease fluctuations of the intraocular pressure. Patients with a quadri-therapy should be monitored regularly as they present high values of intraocular pressure and its fluctuations. A hospitalisation of the patients with 24-hour measurements of the intraocular pressure and blood pressure provides information needed to improve the therapy or decide about surgical interventions.

[Alterations of intraocular pressure in comparison of self- and external-administered topical antiglaucomatosa during diurnal intraocular pressure measurements]

BACKGROUND

The correct self-administration of topical antiglaucomatous eye drops is important for the success of glaucoma treatment. Individual impairment, like increased age, decreased visual acuity, impaired visual-field perception or the frequency of drug appliance may influence a correct application technique and the patients compliance and therewith intraocular pressure (IOP). The aim of this study was to explore alterations of IOP due to self versus external administration (by trained medical personnel) of topical antiglaucomatous eye drops due to impairing factors.

MATERIAL AND METHODS

A prospective analysis was undertaken of 123 patients with primary chronic open-angle glaucoma receiving a diurnal intraocular pressure (DIP) measurement over 72 hours at our department. During the first 24 hours, the application of topical eye drops was self-administered by patients (SA), while the application of eye drops within the following 48 hours was performed by trained medical personnel (EA). Alterations of mean intraocular pressure (MIP) and diurnal fluctuations (DF) between EA and SA were analysed with regard to initial IOP, restrictions of visual field perception, visual acuity, age, general health status and frequency of daily eye drop administration.

RESULTS

Overall comparable MIP in SA and EA was seen. 19.2-43.9 % of the patients with an initial IOP ≥ 11 mmHg showed beneficial effects of EA with lowering of IOP under 15.5 mmHg. 27.6 % of the patients showed lowering of DF < 5 mmHg due to EA. EA influenced DF beneficially in cases of poor visual acuity (≤ 0.1, - 0.8 mmHg) and frequent drop administration (- 0.75 mmHg).

CONCLUSIONS

Subpopulations of investigated patients showed lowering of MIP due to EA, although EA showed no MIP lowering effects in comparison with SA in general. Glaucoma-impaired patients show decreased DF by EA. Particularly beneficial influences to DF by EA were observed due to impaired visual acuity and frequent drop administration. We recommend a 72-hour DIP to evaluate individual parameters influencing the success of topical glaucomatous treatment. The benefit of EA in patients with certain impairments should be the subject of further investigations.

[Successful treatment of Fusarium-associated keratitis with multiresistant pathogen and multimorbid patient]

A 75-year-old man (not a contact lens wearer) presented with Fusarium-associated hypopyon keratitis. After several weeks of empirical and subsequently targeted antimycotic treatment, no considerable improvement was observed. However, after sclerokeratoplasty (11.2 × 11.2 mm) combined with prolonged antimycotic therapy a good local result with relapse-free long-term follow-up was achieved.

[BOON (Bonn ophthalmology online network). Concept of an integrative databank for monitoring patients under intravitreal therapy]

BACKGROUND

Previous studies have proven that long-lasting success in the therapy of neovascular age-related macular degeneration (AMD) and other neovascular retinal diseases depends on monthly follow-up examinations to assess visual acuity and retinal morphology.

MATERIALS AND METHODS

The interactive database Bonn ophthalmology online network (BOON) offers a platform for patient monitoring, increasing control reliability and providing a tool for permanent communication between treating centers and referring ophthalmologists. The BOON data-based project started in 2009 at the department of ophthalmology at Bonn University and ten referring ophthalmology practices. It was programmed to communicate diagnostic findings, images and patient appointments online. In order to react promptly the system gave immediate notice if patients had missed a follow-up appointment or the condition had worsened. Patients were recruited in 2009 and 2010 and were followed for 1 year. Each patient had an electronic master file with several registers in which, besides personal data, precise diagnostic findings, imaging and reports were quickly and easily entered by means of detailed check box and drop-down menus. Each follow-up was registered and an alert email was sent to the referring physician in cases of missed appointments or disease progression.

RESULTS AND CONCLUSIONS

The BOON database supports the requirements for a fast and detailed communication between treating and referring physicians in the treatment of patients with AMD as well as other retinal diseases. It was programmed to support data exchange and monthly control visits and thus a better patient management. Results will show whether this helps to enhance long-term treatment success in neovascular diseases.

[Use of nanoparticles in ophthalomology]

Nanotechnology, the manufacture and use of structures and implements of around a few 100 nm in size, is becoming a key technology of the twenty-first century. An important element for the manufacture of nanoparticles is gold. Gold nanoparticles can be custom made and chemically modified in their size and form. Initial investigations have shown that they are physiologically non-hazardous. A potential application is in neovascular age-related macular degeneration. Gold nanoparticles of suitable dimensions introduced into newly forming blood vessels can be targeted and heated which selectively destroys these blood vessels. This principle has already been demonstrated in cultivated endothelial cells.

Intravitreales Bevacizumab bei der neovaskulären altersabhängigen Makuladegeneration

The efficacy and safety of the therapeutic anti-VEGF concept has already been demonstrated for pegaptanib and ranibizumab. Bevacizumab acts as an antibody against all VEGF-A isoforms and has been developed for oncological indications with intravenous application. Initial reports on intravitreal administration in patients with neovascular age-related macular disease (AMD) have shown beneficial morphological and functional effects. In the meantime, bevacizumab has been used off-label in thousands of patients with AMD. However, data from prospective, controlled, randomized trials on both safety and efficacy are lacking. Herein recent experiences with bevacizumab are summarized and discussed. Furthermore, a web-based platform for online data registration and pooled analyses is presented.

Lower limits of fluorescein and indocyanine green dye for digital cSLO fluorescence angiography

BACKGROUND

With the advent of digital confocal scanning laser ophthalmoscopy it is possible to detect low levels of fluorescence. Here we used a novel confocal scanning laser ophthalmoscope (cSLO) to determine lower limits of dye required for fluorescein (FL) and indocyanine green (ICG) angiography.

METHODS

A cSLO (Heidelberg retina angiograph 2, Heidelberg Engineering, Dossenheim, Germany) with an optically pumped solid state laser (488 nm) for FL and a diode laser (790 nm) for ICG angiography (FL/ICG-A) was used. 62 FL-As were performed in 53 patients and 45 ICG-As were performed in 39 patients with neovascular age related macular degeneration. The volume and overall dye content of bolus injections was gradually tapered (FL: 500 mg, 250 mg, 200 mg, 166 mg, 100 mg; ICG: 25 mg, 20 mg, 15 mg, 10 mg, 5 mg, 2.5 mg), while dye concentrations were kept constant at 100 mg/ml for FL and at 5 mg/ml for ICG. Images were obtained 1, 5, 15, and 30 minutes after dye injection. Image quality was evaluated by two independent readers using standardised criteria.

RESULTS

For amounts down to 166 mg for FL and to 5 mg for ICG, sufficient image quality was achieved during all phases following injection. Only late phase images showed less contrast compared to typically used dye amounts, which was irrelevant for interpretation and clinical management.

CONCLUSIONS

With the increased sensitivity of this novel cSLO system, amounts of injected dye during FL-A can be reduced to one third for FL and to one fifth for ICG without relevant loss of image quality or information compared to conventionally used dye levels. These amounts can be used for routine angiography and allow relevant savings for units performing FL-A.