Comparability of input parameters in the German Retina.net ROP registry and the EU-ROP registry - An exemplary comparison between 2011 and 2021

PURPOSE

The German Retina.net ROP registry and its Europe-wide successor, the EU-ROP registry, collect data from patients treated for ROP. This analysis compares input parameters of these two registries to establish a procedure for joint analyses of different registry data using exemplary datasets from the two registries.

METHODS

Exemplary datasets from the two databases over a 1-year period each (German Retina.net ROP Registry, 2011, 22 infants; EU-ROP Registry, 2021, 44 infants) were compared. The parameters documented in the two databases were aligned and analysed regarding demographic parameters, treatment modalities, complications within first 24 h and retreatments.

RESULTS

The current analysis showed that data can be aligned for joint analyses with some adjustments within the data structure. The registry with more detailed data collection (EU-ROP) needs to be reduced regarding granularity in order to align the different registries, as the registry with lower granularity determines the level of analyses that can be performed in a comparative approach. In the exemplary datasets, we observed that the overall most common ROP severity in both registries was zone II, 3+ (2011: 70.5%; 2021: 65%), with decreasing numbers of clock hours showing preretinal neovascularisations (2011: 10-12 clock hours in 29% of cases, 2021: 4-6 clock hours in 38%). The most prevalent treatment method was laser coagulation in 2011 (75%) and anti-VEGF therapy in 2021 (86.1%). Within the anti-VEGF group, all patients were treated with bevacizumab in 2011 and with ranibizumab in 2021. Retreatment rates were comparable in 2011 and 2021.

CONCLUSION

Data from two different ROP registries can be aligned and jointly analysed. The analysis reveals a paradigm shift in treatment modalities, from predominantly laser to anti-VEGF, and within the anti-VEGF group from bevacizumab to ranibizumab in Germany. In addition, there was a trend towards earlier treatment in 2021.

Implementing and evaluating a fully functional AI-enabled model for chronic eye disease screening in a real clinical environment

BACKGROUND

Artificial intelligence (AI) has the potential to increase the affordability and accessibility of eye disease screening, especially with the recent approval of AI-based diabetic retinopathy (DR) screening programs in several countries.

METHODS

This study investigated the performance, feasibility, and user experience of a seamless hardware and software solution for screening chronic eye diseases in a real-world clinical environment in Germany. The solution integrated AI grading for DR, age-related macular degeneration (AMD), and glaucoma, along with specialist auditing and patient referral decision. The study comprised several components: (1) evaluating the entire system solution from recruitment to eye image capture and AI grading for DR, AMD, and glaucoma; (2) comparing specialist's grading results with AI grading results; (3) gathering user feedback on the solution.

RESULTS

A total of 231 patients were recruited, and their consent forms were obtained. The sensitivity, specificity, and area under the curve for DR grading were 100.00%, 80.10%, and 90.00%, respectively. For AMD grading, the values were 90.91%, 78.79%, and 85.00%, and for glaucoma grading, the values were 93.26%, 76.76%, and 85.00%. The analysis of all false positive cases across the three diseases and their comparison with the final referral decisions revealed that only 17 patients were falsely referred among the 231 patients. The efficacy analysis of the system demonstrated the effectiveness of the AI grading process in the study's testing environment. Clinical staff involved in using the system provided positive feedback on the disease screening process, particularly praising the seamless workflow from patient registration to image transmission and obtaining the final result. Results from a questionnaire completed by 12 participants indicated that most found the system easy, quick, and highly satisfactory. The study also revealed room for improvement in the AMD model, suggesting the need to enhance its training data. Furthermore, the performance of the glaucoma model grading could be improved by incorporating additional measures such as intraocular pressure.

CONCLUSIONS

The implementation of the AI-based approach for screening three chronic eye diseases proved effective in real-world settings, earning positive feedback on the usability of the integrated platform from both the screening staff and auditors. The auditing function has proven valuable for obtaining efficient second opinions from experts, pointing to its potential for enhancing remote screening capabilities.

TRIAL REGISTRATION

Institutional Review Board of the Hamburg Medical Chamber (Ethik-Kommission der Ärztekammer Hamburg): 2021-10574-BO-ff.

Treated Cases of Retinopathy of Prematurity in Germany: 10-Year Data from the Retina.net Retinopathy of Prematurity Registry

PURPOSE

To analyze changes in demographic parameters and retreatment patterns over a 10-year period in a clinical routine setting of infants with retinopathy of prematurity (ROP) requiring treatment documented in the German Retina.net ROP registry.

DESIGN

Multicenter, noninterventional, observational registry study recruiting patients treated for ROP.

SUBJECTS

A total of 692 eyes of 353 infants treated for ROP were documented in the Retina.net ROP registry over a 10-year period between 2011 and 2020. These cases cover about 15% of all infants treated for ROP in Germany.

METHODS

The Retina.net ROP registry was established in 2012 to jointly collect information on infants treated for ROP. The database collects information on demographic parameters (gestational age [GA], birth weight, neonatal comorbidities) as well as treatment parameters (type of treatment, weight and age at treatment, and stage of ROP). A total of 19 centers contributed to the analysis. This is the 10-year analysis of data from 2011 to 2020, in which we focus on changes over time regarding the respective parameters.

MAIN OUTCOME MEASURES

Changes over time in demographic parameters and treatment patterns for ROP in Germany.

RESULTS

The overall incidence of treatment requiring ROP was 3.5% of all infants screened for ROP at participating centers. Gestational age, weight at birth, and weight at treatment remained stable over the 10-year period, whereas postmenstrual and postnatal age at treatment increased moderately but statistically significantly over the years. The most prevalent ROP severity stage at treatment was stage 3+ in zone II (76.6% of all treated eyes). Treatment patterns changed considerably from predominantly laser treatments in 2011 (75% of all treated eyes) to predominantly ranibizumab treatments in 2020 (60.9% of all treated eyes). The overall retreatment rate was 15.6%. Retreatment rates differed between initial treatment modalities (14.1% after laser coagulation, 12% after bevacizumab and 24.5% after ranibizumab). Treatment-associated systemic or ophthalmic complications were rare.

CONCLUSIONS

This data analysis represents one of the largest documented cohorts of infants treated for ROP. The data on demographic parameters and treatment patterns provide useful information for further improvement of ROP management.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Pupillotonia after endolaser retinopexy during vitrectomy for retinal detachment: a prospective cohort study comparing circumferential and focal retinopexy

PURPOSE

To determine differences in postoperative pupil diameter in eyes that undergo pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) with endolaser retinopexy (ELR), comparing 360° vs focal ELR.

METHODS

Patients with uncomplicated RRD who underwent PPV were prospectively analysed regarding the postoperative pupil diameter difference (PDD) between the affected eye and the partner eye. Group 1 underwent 360° ELR and group 2 received focal ELR. Postoperative vision and complications, including redetachment rate, macular oedema and epiretinal membrane formation, were also compared.

RESULTS

A total of 72 patients, 42 in group 1 and 30 in group 2, were analysed. PDD, as observed at 6 weeks, was significantly greater than the preoperative values in both groups 1 and 2. It increased by a mean of 1±1.11 mm in group 1 and by 0.5±0.78 in group 2. This initial increase in PDD receded over time, but remained statistically significant in both groups, even at 6 months. The top 20% of patients with the largest PDD change comprised 13 out of 15 eyes from group 1, which was a statistically significant overrepresentation (p=0.0435).

CONCLUSIONS

Moderate pupillotonia was induced post-ELR in vitrectomy and correlated to the extent of ELR. The pupillotonia effect of ELR was significantly less marked in pseudophakic eyes.

Terson Syndrome in Patients with Aneurysmal Subarachnoid Hemorrhage: A 10-Year Single-Center Experience

BACKGROUND

Terson syndrome (TS), an intraocular hemorrhage associated with aneurysmal subarachnoid hemorrhage (aSAH), occurs in up to 46% of all patients with subarachnoid hemorrhage. Despite its high incidence, TS is underrepresented in the literature, and patients with aSAH are sometimes not systematically evaluated for the presence of TS in clinical practice. This work aims to raise awareness of TS, reevaluate previous scientific findings, describe risk factors associated with the occurrence of TS, and present our local diagnostic and treatment concept.

METHODS

All patients with aSAH treated at our institution between October 2010 and May 2020 were included in this retrospective study. The frequency of ophthalmological screening by indirect funduscopy, as well as the results, was investigated. In addition, the collection and statistical analysis of epidemiological and clinical data was performed using χ2, Kruskal-Wallis, and analysis of variance testing; multivariate regression; and receiver operating characteristic analysis. The significance level was set at p < 0.05.

RESULTS

A total of 617 patients were treated for aSAH in our institution. Of these, 367 patients (59.5%) were ophthalmologically examined for the presence of TS. The rate of TS in the examined patients was 21.3% (n = 78). Patients with TS had significantly higher Fisher and World Federation of Neurosurgical Societies (WFNS) scores (p < 0.0001). Regression analyses showed WFNS grade (p = 0.003) and the occurrence of seizures (p = 0.002) as independent predictors of TS, as did receiver operating characteristic analyses, which had a significant area under the curve of 0.66 for the combination of WFNS grade and seizures. For 12 (15.4%) patients, the TS had to be surgically treated by pars plana vitrectomy in a total of 14 eyes, which resulted in significant improvement of visual function in all patients: mean preoperative best-corrected visual acuity was 0.03 (± 0.08) versus 0.76 (± 0.21) postoperatively (p < 0.001).

CONCLUSIONS

TS is a common complication in patients with aSAH, affecting approximately one in five patients. A higher WFNS grade and the occurrence of seizures are associated with TS; therefore, screening for TS should be performed in these patients.

Comparison of treatment outcomes of 360° intraoperative laser retinopexy and focal laser retinopexy with pars plans vitrectomy in patients with primary rhegmatogenous retinal detachment

BACKGROUND

This study was to compare the outcomes of 360° intra-operative laser retinopexy (ILR) and focal laser retinopexy in treating patients with pars plans vitrectomy (PPV) for primary rhegmatogenous retinal detachment (RRD). To identify other potential risk factors for retinal re-detachment after primary PPV.

METHODS

This was a retrospective cohort study. Three hundred and forty-four consecutive cases of primary rhegmatogenous retinal detachment treated with PPV were included between July 2013 and July 2018. Clinical characteristics and surgical outcomes were compared between focal laser retinopexy and additional 360° intra-operative laser retinopexy groups. Both univariate and multiple variable analysis were used to identify potential risk factors for retinal re-detachment.

RESULTS

Median follow-up was 6.2 months (Q1, Q3:2.0, 17.2). As estimated with survival analysis, the 360º ILR group had the incidence of 9.74% and focal laser 19.54% at 6 months postoperatively. At 12 months postoperatively the difference was 10.78% vs. 25.21%. The difference in survival rates was significant (p = 0.0021). In multivariate Cox regression, the risk factors for retinal re-detachment were without additional 360° ILR, diabetes and macula off before the primary surgery (relatively OR = 0.456, 95%-CI [0.245-0.848], p < 0.05; OR = 2.301, 95% CI [1.130-4.687], p < 0.05; OR = 2.243, 95% CI [1.212-4.149], p < 0.05).

CONCLUSION

Additional 360° ILR group had a significantly lower rate of retinal re-detachment when compared with focal laser retinopexy group. Our study also elucidated that diabetes and macular off before the primary surgery might also be the potential risk factors for higher rate of retinal re-detachment outcome.

TRIAL REGISTRATION

This was a retrospective cohort study.

[Medical holograms for education and training in ophthalmology]

Medical holograms facilitate the learning and advanced medical training in the field of ophthalmology and help to visualize surgical processes with a new abundance of detail. Through implementing three-dimensional datasets the learning process of microsurgical procedures in ophthalmology is facilitated. Furthermore, medical holograms can be used as a multimodal tool for patient education.

Simultaneous screening and classification of diabetic retinopathy and age-related macular degeneration based on fundus photos—a prospective analysis of the RetCAD system

AIM: To assess the accuracy of an artificial intelligence (AI) based software (RetCAD, Thirona, The Netherlands) to identify and grade age-related macular degeneration (AMD) and diabetic retinopathy (DR) simultaneously based on fundus photos. METHODS: This prospective study included 1245 eyes of 630 patients attending an ophthalmology day-care clinic. Fundus photos were acquired and parallel graded by the RetCAD AI software and by an expert reference examiner for image quality, and staging of AMD and DR. Adjudication was provided by a second expert examiner in case of disagreement between the AI software and the reference examiner. Statistical analysis was performed on eye-level and on patient-level, by summarizing the individual image level-gradings into and eye-level or patient-level score, respectively. The performance of the RetCAD system was measured using receiver operating characteristics (ROC) analysis and sensitivity and specificity for both AMD and DR were reported. RESULTS: The RetCAD achieved an area under the ROC (Az) of 0.926 with a sensitivity of 84.6% at a specificity of 84.0% for image quality. On image level, the RetCAD software achieved Az values of 0.964 and 0.961 with sensitivity/specificity pairs of 98.2%/79.1% and 83.9%/93.3% for AMD and DR, respectively. On patient level, the RetCAD software achieved Az values of 0.960 and 0.948 with sensitivity/specificity pairs of 97.3%/73.3% and 80.0%/90.1% for AMD and DR, respectively. After adjudication by the second expert examiner sensitivity/specificity increases on patient-level to 98.6%/78.3% and 100.0%/92.3% for AMD and DR, respectively. CONCLUSION: The RetCAD offers very good sensitivity and specificity compared to manual grading by experts and is in line with that obtained by similar automated grading systems. The RetCAD AI software enables simultaneous grading of both AMD and DR based on the same fundus photos. Its sensitivity may be adjusted according to the desired acceptable sensitivity and specificity. Its simplicity cloud base integration allows cost-effective screening where routine expert evaluation may be limited.

Predicting speed of progression of lens opacification after pars plana vitrectomy with silicone oil

Purpose

An increasing number of posterior segment disorders is routinely managed with pars plana vitrectomy (PPV). In older, phakic patients cataract formation is expected within the first two years after surgery. For younger patients its progression is individually fluctuating. This study uses an objective quantitative measurement for lens-status-monitoring after PPV with silicone oil to derive predictions for progression and severity of post-operative lens opacification evaluated in patients with rhegmatogenous retinal detachment (RRD).

Methods

Data acquisition was performed prospectively between March 2018 and March 2021. PentacamHR® Nucleus Staging mode (PNS) was used to objectively gather data about nuclear cataracts after PPV at different time points. Data was grouped into training and test sets for a mathematical prediction model. Via backward variable selection method a mathematical formula was set up by means of which predictions about lens densitometry (LD) can be calculated.

Results

20 males [58.8%] and 14 females [41.2%] matched the inclusion criteria (mean age 50.6 years [23–75; ±12.3]). Average follow-up was 8.1 months (3,4–17.4; ±3.4). Mean baseline LD of the treated and fellow eye before surgery was 11.1% (7.7%-17.6%; ±2.0) and 11.2% (7.7%-14.8%; ±1.5), respectively. Predicted LD values by the model for five pre-selected patients closely match the observed data with an average deviation of 1.06%.

Conclusions

Using an objective parameter like LD delivered by the PentacamHR® PNS mode additionally to the patient’s age allows us to make an individual prediction for any time after PPV with silicone oil due to RRD for all ages. The accuracy of the model was stronger influenced by baseline LD as cofactor in the equation than patient’s age. The application for the prediction lens opacification [which can be accessed for free under the following link (https://statisticarium.com/apps/sample-apps/LensDensityOil/)] can help vitreoretinal surgeons for patient consultation on the possibility to combine PPV with cataract surgery.

A novel temporary keratoprosthesis technique for vitreoretinal surgery

AIM

To investigate the safety of vitreoretinal surgery when using a soft contact lens as a temporary keratoprosthesis (TKP) in patients with severe corneal opacifications.

METHODS

Three patients with simultaneous corneal and vitreoretinal pathology were treated with a soft contact lens that was used as a TKP to facilitate vitreoretinal surgery. The soft contact lens was fixated with sutures onto the globe so that no leakage was possible.

RESULTS

Vitreoretinal surgery with excellent fundus view was possible in all cases. The soft contact lens allowed safe central and peripheral vitrectomy. Surgery was successful in all cases.

CONCLUSION

A soft contact lens properly fixated on the globe can successfully replace a TKP. This surgical procedure has several advantages like one size fits all, low costs, and easy access to the material.

Reliability of the ocular trauma score for the predictability of traumatic and post-traumatic retinal detachment after open globe injury

AIM

To elucidate the question of whether the ocular trauma score (OTS) and the zones of injury could be used as a predictive model of traumatic and post traumatic retinal detachment (RD) in patients with open globe injury (OGI).

METHODS

A retrospective observational chart analysis of OGI patients was performed. The collected variables consisted of age, date, gender, time of injury, time until repair, mechanism of injury, zone of injury, injury associated vitreous hemorrhage, trauma associated RD, post traumatic RD, aphakia at injury, periocular trauma and OTS in cases of OGI.

RESULTS

Totally 102 patients with traumatic OGI with a minimum of 12mo follow-up and a median age at of 48.6y (range: 3-104y) were identified. Final best corrected visual acuity (BCVA) was independent from the time of repair, yet a statistically significant difference was present between the final BCVA and the zone of injury. Severe trauma presenting with an OTS score I (P<0.0001) or II (P<0.0001) revealed a significantly worse BCVA at last follow up when compared to the cohort with an OTS score >III. OGI associated RD was observed in 36/102 patients (35.3%), whereas post traumatic RD (defined as RD following 14d after OGI) occurred in 37 patients (36.3%). OGI associated RD did not correlate with the OTS and the zone of injury (P=0.193), yet post traumatic RD correlated significantly with zone III injuries (P=0.013).

CONCLUSION

The study shows a significant association between lower OTS score and zone III injury with lower final BCVA and a higher number of surgeries, but only zone III could be significantly associated with a higher rate of RD.

Prediction model of free flaps in microkeratome-assisted LASIK

Purpose

To identify mechanical factors, as well as patients’ biometric and surgeons’ experience factors that correlate with the FF incidence in microkeratome (MK)-assisted LASIK and to construct a predictive model based on these parameters.

Methods

55,700 consecutive LASIK treatments of 28,506 patients between January 2017 and April 2020 done by 50 surgeons in 10 centers, all with Sub Bowman Keratome (SBK) and 90μ head (OUP) were analyzed retrospectively for the incidence of FF and their correlation to mean keratometry, central corneal thickness, MK ring height and stop, as well as surgeons’ experience. A prediction model was built and tested for sensitivity and specificity.

Results

The incidence of FF using the SBK MK was 0.276%. Risk factors were low central corneal thickness, very flat (-1) or very thick (+2) ring height, and higher stop values (p<0.001). Mean keratometry and low surgeon experience were not correlated to FF incidence. A prediction model with a cut-off FF risk of 0.274%, a 76% specificity, and a 73% sensitivity was applied.

Conclusions

Free flaps are rarely seen in modern MK LASIK. However, the incidence of this complication using the SBK MK increases using higher stop values, very thick and very thin MK rings, and in eyes with thin corneas.

Lens densitometry for assessment and prediction of cataract progression after pars plana vitrectomy with C3F8-gas for retinal detachment

Purpose

Lens opacification is a common complication after pars plana vitrectomy (PPV) and knowing its progression would facilitate consulting patients. The purpose of this study was to evaluate a quantitative model for lens-status-monitoring after PPV with C3F8 gas. Our model was evaluated in rhegmatogenous retinal detachment (RRD) patients of various age and lens densitometry (LD).

Methods

Data between March 2018 and March 2020 were evaluated retrospectively. LD measurements of the PentacamHR® Nucleus Staging mode (PNS) were used to quantify lens opacification over time. A mixed-effect regression model was designed, to enable LD predictions at any time postoperatively. Calculations were based on patient’s age and baseline LD as dependent variables. Six patients were randomly excluded during model development, to be used for testing its power afterwards.

Results

34 patients (male 19 [55.9%], female 15 [44.1%]) matched the inclusion criteria. Average age was 58.5 years (32–77;±4.3) and average follow-up was 7.2 months (3,4–23.1;±1,8). Mean baseline LD of the treated and fellow eye before surgery were 10.9% (8.7%-14.8%;±0.8) and 10.7% (8.5%-14.1%;±0.6), respectively. Using our prediction model, LD values for the six pre-selected patients closely match the observed data with an average deviation of 1.07%.

Conclusions

Evaluation of age and baseline LD using a mixed-effect regression model might predict cataract progression in RRD patients treated with PPV and C3F8-gas. Such a tool could be considered during cataract surgery consultation in these patients.

[Treatment of postoperative endophthalmitis : Operate or only inject?]

BACKGROUND

Postoperative endophthalmitis is among the most feared complications encountered after intraocular surgery. A prompt diagnosis and initiation of treatment are crucial for the visual prognosis, which also depends on the causative microorganism. Despite advances in prevention and the availability of more epidemiological data, most of the evidence for treatment dates back to a single study, the early vitrectomy study (EVS) carried out in the early 1990s. The EVS showed that vitrectomy with intravitreal antibiotics was superior to intravitreal antibiotics alone, only when visual acuity was light perception or below. The addition of systemic antibiotics did not have any benefits. Over the last 30 years, however, surgical techniques have continued to evolve and the medicinal options have also been expanded. Moreover, the EVS examined only endophthalmitis after cataract surgery and strictly speaking the results cannot be transferred to endophthalmitis from other causes.

OBJECTIVE

This review discusses the current evidence for the different treatment modalities of the most important types of postoperative endophthalmitis.

CONCLUSION

The EVS provided important guidelines for the initial management of endophthalmitis and these guidelines remain relevant to this day; however, in view of the refinement of surgical techniques, novel treatment options, especially the nowadays continuously growing number of intravitreal injections and even some new antibiotics, it would be desirable if new controlled trials addressing the treatment of endophthalmitis would be performed.

Bevacizumab as a treatment option for choroidal neovascularisation due to large optic nerve drusen in a 14-year-old girl

Purpose: To report the effects of a single intravitreous injection of bevacizumab for the treatment of secondary choroideal neovascularisation due to large optic disc drusen.

Methods: A 14-year-old female patient with painless loss of vision in one eye presented with unusually large optic disc drusen and juxtapapillary choroidal neovascularisation with subretinal hemorrhage. She was treated with a single intravitreous injection of bevacizumab.

Results: Visual acuity increased from 20/100 to 20/25 within 4 weeks after injection and remained at this level during the 12-month follow-up period.

Conclusions: Bevacizumab is a possible primary treatment option for secondary choroidal neovascularisation due to large optic disc drusen in children as an alternative to other more invasive or complex procedures.

Surgical management of submacular hemorrhage due to n-AMD: a comparison of three surgical methods

Background

To compare and assess the efficacy of three surgical methods for the treatment of acute submacular hemorrhage (ASH): pneumatic displacement with C2F6, in combination with intravitreal injection of bevacizumab and rtPA, pars plana vitrectomy (PPV) with intravitreal injection of gas (C2F6), bevacizumab and subretinal injection of recombinant tissue plasminogen activator (rtPA), pars plana vitrectomy (PPV) with intravitreal injection of gas (C2F6), bevacizumab and intravitreal injection of recombinant tissue plasminogen activator (rtPA).

Methods

The study included 85 patients with ASH. In the group without PPV (A), patients were treated with intravitreal injection of C2F6, bevacizumab and rtPA. In the second and third group, patients underwent a PPV, intravitreal injection of bevacizumab, pneumatic displacement with C2F6 and a subretinal (B) or intravitreal (C) injection of recombinant tissue plasminogen activator (rt PA).

Results

In group A, mean BCVA increased from preop logMAR 1.41 to 1.05, in group B from 1.46 to 1.28 and in group C from 1.63 to 1.33. In group A, CFT changed from 764 ± 340 μm at time point 0 to 246 ± 153 μm at time point 1, in group B from 987 ± 441 μm to 294 ± 166 μm and in group C from 642 ± 322 μm to 418 ± 364 μm. Patients had an average of 5 injections after surgery.

Conclusion

Our study demonstrates that the three methods are equally effective in improving the morphology and the BCVA of patients with ASH.

Intraocular pressure during neurosurgical procedures in context of head position and loss of cerebrospinal fluid

OBJECTIVE

Perioperative visual loss (POVL) is a rare but serious complication in surgical disciplines, especially in spine surgery. The exact pathophysiology of POVL remains unclear, but elevated intraocular pressure (IOP) is known to be part of it. As POVL is rarely described in patients undergoing intracranial or intradural surgery, the aim of this study was to investigate the course of IOP during neurosurgical procedures with opening of the dura mater and loss of CSF.

METHODS

In this prospective, controlled trial, 64 patients fell into one of 4 groups of 16 patients each. Group A included patients undergoing spine surgery in the prone position, group B patients had intracranial procedures in the prone position, and group C patients were treated for intracranial pathologies in a modified lateral position with the head rotated. In groups A-C, the dura was opened during surgery. Group D patients underwent spine surgeries in the prone position with an intact dura. IOP was measured continuously pre-, peri-, and postoperatively.

RESULTS

In all groups, IOP decreased after induction of anesthesia and increased time dependently after final positioning for the operation. The maximum IOP in group A prior to opening of the dura was 28.6 ± 6.2 mm Hg and decreased to 23.44 ± 4.9 mm Hg directly after dura opening (p < 0.0007). This effect lasted for 30 minutes (23.5 ± 5.6 mm Hg, p = 0.0028); after 60 minutes IOP slowly increased again (24.5 ± 6.3 mm Hg, p = 0.15). In group B, the last measured IOP before CSF loss was 28.1 ± 5.0 mm Hg and decreased to 23.5 ± 6.1 mm Hg (p = 0.0039) after dura opening. A significant IOP decrease in group B lasted at 30 minutes (23.6 ± 6.0 mm Hg, p = 0.0039) and 60 minutes (23.7 ± 6.0 mm Hg, p = 0.0189). In group C, only the lower eye showed a decrease in IOP up to 60 minutes after loss of CSF (opening of dura, p = 0.0007; 30 minutes, p = 0.0477; 60 minutes, p = 0.0243). In group D (control group), IOP remained stable throughout the operation after the patient was prone.

CONCLUSIONS

This study is the first to demonstrate that opening of the dura with loss of CSF during neurosurgical procedures results in a decrease in IOP. This might explain why POVL predominantly occurs in spinal but rarely in intracranial procedures, offers new insight to the pathophysiology of POVL, and provides the basis for further research and treatment of POVL.German Clinical Trials Register (DRKS) no.: DRKS00007590 (drks.de).

Safety and complications after three different surface ablation techniques with mitomycin C: a retrospective analysis of 2757 eyes

BACKGROUND

To evaluate the safety and spectrum of complications of three excimer laser surface ablation techniques (SATs) with an intraoperative application of mitomycin C (MMC) 0.02%. A retrospective, non-comparative large case series.

METHODS

SATs were performed on 2757 eyes with a preoperative spherical equivalent (SE) of - 4.41 ± 2.44 and a Wavelight Allegretto 200 platform. Ablation zone diameters between 6.0 and 7.0 mm were used according to mesopic pupil size. All patients were treated with an intraoperative application of MMC for 30 to 90 s depending on refractive error. The mean follow-up time was > 3 months (107 ± 24 days). Complication range and incidence were analyzed retrospectively and safety index was calculated.

RESULTS

Two thousand seven hundred and fifty-seven eyes met the inclusion criteria for surface ablation. Two thousand five hundred and seventy-three eyes were assigned to alcohol-assisted photorefractive keratectomy (APRK), 135 eyes to transepithelial photorefractive keratectomy (TPRK), and 49 eyes to off-flap epithelial laser in situ keratomileusis (EpiLASIK/EpiK). Overall, the safety index was 1.06 ± 0.28. Haze was graded according to the Fantes scale. Haze incidence rates were highest in the TPRK group (14.81%) and comparably low in APRK (2.95%) and EpiK (4.08%) groups.

CONCLUSIONS

Intraoperative topical application of MMC (0.02%) results in good safety and no severe side effects. However, highest incidence of haze was observed after TPRK. The more frequent peripheral localization of haze might be attributed to large ablation zones and the wavefront optimized ablation profile especially in the PTK modus of the laser platform.

Terson's syndrome - Pathophysiologic considerations of an underestimated concomitant disease in aneurysmal subarachnoid hemorrhage

Terson syndrome (TS) is a common and underestimated concomitant disease in patients suffering from subarachnoid hemorrhage (SAH). Aim of this study was to evaluate the influence of an initial unconsciousness and raised intracranial pressure (ICP) on the development of TS. We performed a retrospective analysis of 213 prospective collected SAH patients screened for TS to investigate the impact of an initial unconsciousness and raised ICP on the development of TS. A univariate analysis followed by a multivariate logistic regression model was performed to identify risk factors that are associated with TS. The findings are all discussed and correlated with the present pathophysiologic considerations of TS. The rate of TS in this study was 23.9%. A higher risk of TS in the univariate analysis was associated with a Glasgow Coma scale⩽7 (p=0.001), higher Hunt and Hess grade (p=0.001), Fisher grade IV (p=0.002), intracerebral hemorrhage (p=0.011), initial unconsciousness (p=0.013) and an ICP of ⩾25mmHg (p<0.001). An ICP of ⩾25mmHg was the only independent predictor for TS in the multivariate analysis (p=0.007). TS patients had a higher mortality (p=0.012) and a higher risk for a worse long-term outcome (p=0.002). Notable that 5 of 51 TS patients (9.8%) in this study developed TS with no raised ICP or initial unconsciousness. Terson syndrome is a common concomitant disease in SAH patients. The pathomechanism leading to TS is not exclusively related to raised ICP levels and/or unconsciousness. However, these factors may be associated with a high percentage of TS.

Scanning laser polarimetry and spectral domain optical coherence tomography for the detection of retinal changes in Parkinson's disease

PURPOSE

Whether retinal degeneration is part of the degenerative processes in patients with Parkinson's disease (PD) is still unclear. This cross-sectional study was undertaken to compare the retinal morphology of patients with PD and healthy controls using spectral domain optical coherence tomography (SD-OCT) and scanning laser polarimetry (SLP).

METHODS

Both eyes of patients with PD (n = 108) and healthy controls (n = 165) were examined using SD-OCT and SLP on the same day. Data on the thickness of the retinal nerve fibre layer (RNFL) of all quadrants and the macular area were acquired by OCT (Cirrus, Zeiss). The SLP device (Glaucoma diagnostics (GDx), Zeiss) measured the RNFL and calculated the nerve fibre index (NFI). All patients and probands were checked for concomitant ocular disorders by an ophthalmologist. Visual acuity, intraocular pressure (IOP), objective refraction and the anterior and posterior segment were assessed.

RESULTS

Patients with PD showed a reduced macular volume and a reduced central subfield thickness in OCT examinations. The RNFL in the different quadrants did not differ significantly from that of controls. SLP data showed a reduced average RNFL thickness, a decreased thickness of the inferior quadrant and an increase of the NFI in patients with PD.

CONCLUSION

PD may be associated with reduced thickness and volume of the macula and a reduced thickness of the RNFL in the inferior quadrant of the retina. Investigations using SD-OCT and SLP revealed distinct but significant differences between patients with PD and healthy controls.

Sustained Neural Stem Cell-Based Intraocular Delivery of CNTF Attenuates Photoreceptor Loss in the nclf Mouse Model of Neuronal Ceroid Lipofuscinosis

A sustained intraocular administration of neurotrophic factors is among the strategies aimed at establishing treatments for currently untreatable degenerative retinal disorders. In the present study we have analyzed the neuroprotective effects of a continuous neural stem (NS) cell-based intraocular delivery of ciliary neurotrophic factor (CNTF) on photoreceptor cells in the nclf mouse, an animal model of the neurodegenerative lysosomal storage disorder variant late infantile neuronal ceroid lipofuscinosis (vLINCL). To this aim, we genetically modified adherently cultivated NS cells with a polycistronic lentiviral vector encoding a secretable variant of CNTF together with a Venus reporter gene (CNTF-NS cells). NS cells for control experiments (control-NS cells) were modified with a vector encoding the reporter gene tdTomato. Clonal CNTF-NS and control-NS cell lines were established using fluorescent activated cell sorting and intravitreally grafted into 14 days old nclf mice at the onset of retinal degeneration. The grafted cells preferentially differentiated into astrocytes that were attached to the posterior side of the lenses and the vitreal side of the retinas and stably expressed the transgenes for at least six weeks, the latest post-transplantation time point analyzed. Integration of donor cells into host retinas, ongoing proliferation of grafted cells or adverse effects of the donor cells on the morphology of the host eyes were not observed. Quantitative analyses of host retinas two, four and six weeks after cell transplantation revealed the presence of significantly more photoreceptor cells in eyes with grafted CNTF-NS cells than in eyes with grafted control-NS cells. This is the first demonstration that a continuous intraocular administration of a neurotrophic factor attenuates retinal degeneration in an animal model of neuronal ceroid lipofuscinosis.

LASIK for spherical refractive myopia: effect of topographic astigmatism (ocular residual astigmatism, ORA) on refractive outcome

Purpose

In eyes with a preoperative plano refractive cylinder, it would appear that there is no rationale for astigmatic treatment. The aim of this retrospective, cross-sectional data analysis was to determine the amount of topographic astigmatism in refractive plano eyes that results in reduced efficacy after myopic laser in situ keratomileusis (LASIK).

Methods

This study included 267 eyes from 267 consecutive myopic patients with a refractive plano cylinder. Receiver operating characteristic analysis was used to find the cut-off values of preoperative ocular residual astigmatism (= topographic astigmatism) that can best discriminate between groups of efficacy and safety indices in preoperative plano refractive cylinder eyes.

Results

Preoperative ocular residual astigmatism (ORA) (or topographic astigmatism) of ≤0.9 diopters (D) resulted in an efficacy index of at least 0.8 statistically significantly more frequently than eyes with a preoperative ORA of >0.9 D. Eyes with a high ORA preoperatively also had a high ORA postoperatively. Regression analysis showed that each diopter of preoperative ORA reduced efficacy by 0.07.

Conclusion

A preoperative corneal astigmatism of ≥0.9 D could (partially) be taken into account in the LASIK design, even if the subjective refractive astigmatism is neutral.

Postoperative refractive error after phacovitrectomy for epiretinal membrane with and without macular oedema

PURPOSE

This study was initiated to investigate whether the presence of macular oedema influenced intraocular lens (IOL) power calculation in eyes with epiretinal membrane.

METHODS

The files of patients undergoing combined phacoemulsification were retrospectively reviewed. Two groups were defined according to presence of macular oedema. The main outcome measure was the IOL power prediction error (PE). Secondary outcome measures were the correlation between preoperative macular thickness, absolute change of macular thickness and dioptric shift. The mean postoperative PE achieved with the Haigis formula was compared with the PE that would have been obtained had the SRKII and HofferQ formulas been used.

RESULTS

We investigated 47 eyes of 47 consecutive patients. Regardless of the IOL formula used, the PE was on average higher in eyes without macula oedema (group 1). The myopic dioptric shift was dependent on preoperative macular thickness and absolute change of macular thickness. This association was more markedly pronounced in group 1.

CONCLUSIONS

Increased retinal thickness is the main cause for underestimation of the cornea-photoreceptor layer distance, and therefore could contribute to inaccuracy in IOL power calculations. The current results show that a myopic shift tends to be less pronounced in cases where a macula oedema is present. Eyes with pure traction have less predictable refractive results in terms of higher PE and dioptric shift.

Depression, anxiety, and disturbed sleep in glaucoma

Although it has been suggested that glaucoma is associated with circadian misalignment, sleep disorder, anxiety, and depression, these comorbid conditions have not received much attention. This study provides evidence for a significantly higher prevalence of depression, trait anxiety, and sleep disturbances in patients with progressed glaucoma, as compared with glaucoma patients with no or minor visual field defects (VFD). Logistic-regression analyses suggest that severe VFD constitute a significant predictor of depression, trait-anxiety, and sleep disturbance. Results indicate the necessity of regular screening and psychochronobiological treatment in glaucoma patients.

Genetically modified neural stem cells for a local and sustained delivery of neuroprotective factors to the dystrophic mouse retina

A continuous intraocular delivery of neurotrophic factors (NFs) is being explored as a strategy to rescue photoreceptor cells and visual functions in degenerative retinal disorders that are currently untreatable. To establish a cell-based intraocular delivery system for a sustained administration of NFs to the dystrophic mouse retina, we used a polycistronic lentiviral vector to genetically modify adherently cultivated murine neural stem (NS) cells. The vector concurrently encoded a gene of interest, a reporter gene, and a resistance gene and thus facilitated the selection, cloning, and in vivo tracking of the modified cells. To evaluate whether modified NS cells permit delivery of functionally relevant quantities of NFs to the dystrophic mouse retina, we expressed a secretable variant of ciliary neurotrophic factor (CNTF) in NS cells and grafted the cells into the vitreous space of Pde6b(rd1) and Pde6b(rd10) mice, two animal models of retinitis pigmentosa. In both mouse lines, grafted cells attached to the retina and lens, where they differentiated into astrocytes and some neurons. Adverse effects of the transplanted cells on the morphology of host retinas were not observed. Importantly, the CNTF-secreting NS cells significantly attenuated photoreceptor degeneration in both mutant mouse lines. The neuroprotective effect was significantly more pronounced when clonally derived NS cell lines selected for high expression levels of CNTF were grafted into Pde6b(rd1) mice. Intravitreal transplantations of modified NS cells may thus represent a useful method for preclinical studies aimed at evaluating the therapeutic potential of a cell-based intraocular delivery of NFs in mouse models of photoreceptor degeneration.

Subjective pain, visual recovery and visual quality after LASIK, EpiLASIK (flap off) and APRK - a consecutive, non-randomized study

INTRODUCTION

Laser in situ keratomileusis (LASIK) is superior to surface ablation techniques (SAT) such as alcohol photorefractive keratectomy (APRK) or Epi-LASIK (EpiK) in terms of visual recovery and postoperative pain. This study compares subjective symptoms and visual recovery of two different SATs with LASIK.

MATERIALS AND METHODS

One hundred and twenty seven patients were operated using one of the three techniques. Patients filled out a questionnaire describing symptoms assessing subjective visual recovery on a linear scale from 'not functioning' to 'full visual function' and pain on a linear scale from 'no pain' to 'severe daily pain'. Subjective symptoms such as halos, double vision, low night vision, reduced contrast and dry eyes were also evaluated.

RESULTS

Visual recovery was faster and discomfort symptoms less pronounced with the LASIK than with surface ablation procedures. More pain was reported after APRK than after EpiK (flap-off technique) in the early postoperative period, with a maximum of pain on postoperative days 3-4. Subjective visual recovery showed no statistically significant difference between the two surface ablation procedures. Halos, double vision, low night vision, reduced contrast and dry eyes were more extensively reported by the EpiK than the APRK group and were less pronounced in the LASIK than in the SAT group.

DISCUSSION AND CONCLUSIONS

Our study does not uniformly support the previously published favourable results of EpiK compared to APRK with regard to subjective recovery of vision and postoperative pain.

Bilateral Achromobacter xylosoxidans keratitis after laser in situ keratomileusis

A 31-year-old man was referred to us 2 months after bilateral laser in situ keratomileusis (LASIK). On presentation, the corrected distance visual acuity was hand motion in the right eye and 20/25 in the left eye. Slitlamp examination showed a diffuse central stromal infiltrate, flap melting, and hypopyon in the right eye and marked interface opacities with crystal-like edges in the left eye. Flap lift and irrigation were performed. Because of the progressive keratitis, penetrating keratoplasty (PKP) was done in both eyes. Achromobacter xylosoxidans was isolated from both corneal buttons, and therapy was changed to chloramphenicol prednisolone eyedrops 8 times a day and intravenous meropenem 500 mg 3 times a day according to sensitivity testing. Two months after surgery, both transplants remained clear.