Marc Töteberg-Harms

Reproducibility of retinal nerve fiber layer thickness measurements using the eye tracker and the retest function of Spectralis SD-OCT in glaucomatous and healthy control eyes.

PURPOSE To evaluate the impact of Spectralis self-acting eye-tracking (eye tracker) and retest software on the reproducibility of retinal nerve fiber layer (RNFL) thickness measurements in glaucomatous and healthy control eyes by SD-OCT. METHODS RNFL thickness was measured in 56 normal and 47 glaucomatous eyes by one operator within one session with a brief rest between measurements. Three measurements were taken with the eye tracker and the retest function engaged (method A), and three measurements were taken without the eye tracker and without the retest function (method B). Method A and B measurements were taken alternately. RESULTS Reliability, measured by intraclass correlation coefficient (ICC) for absolute agreement and coefficient of variation (COV), was calculated for the global mean RNFL thickness (G), for each sector and for the peripapillary bundle. The ICC (and lower 95% confidence interval [CI]) for the global mean RNFL thickness (G) for method A measurements in both normal and glaucomatous eyes was 0.99 (0.98 CI). In glaucomatous eyes, the COV for method B measurements was between 2.7% and 10.5%, and between 1.3% and 3.5% for method A measurements. CONCLUSIONS The reproducibility of RNFL measurements with Spectralis SD-OCT is excellent in both normal and glaucomatous eyes and can be significantly improved by using the eye tracker and retest software. The gain of reproducibility by using the software is significantly higher in glaucomatous eyes than in normal eyes. These findings suggest that software applications are capable of significantly improving the reproducibility of RNFL thickness measurements.

Repeatability of nerve fiber layer thickness measurements in patients with glaucoma and without glaucoma using spectral-domain and time-domain OCT

BackgroundThe aim of this work is to assess the repeatability of spectral-domain-OCT (SD-OCT) retinal nerve fiber layer thickness (RNFL) thickness measurements in a non-glaucoma group and patients with glaucoma and to compare these results to conventional time-domain-OCT (TD-OCT).MethodsIn a prospective, comparative, observational case-control study, 50 eyes of 25 non-glaucoma and 22 eyes of 11 patients with primary open angle glaucoma (POAG) were included. SD-OCT and TD-OCT circle scans were centered on the optic disc. In each eye, OCT scans were performed three times by two independent observers. RNFL thickness was measured in four quadrants around the optic disc. In addition, the overall mean RNFL thickness was assessed. Intraclass correlation coefficients (ICC) and coefficients of variation (COV) were calculated. Inter-observer and inter-OCT repeatability was visualized by using Bland–Altman analysis.ResultsIntra-observer repeatability for TD- OCT was good with an ICCmean RNFL thickness of 0.939 in non-glaucomas and 0.980 in glaucomatous eyes. For SD-OCT, intra-observer repeatability was higher with an ICC of 0.989 for non-glaucomas and 0.997 for glaucomatous eyes. COVs for TD-OCT ranged from 2.9–7.7% in non-glaucomas and from 6.0–13.3% in glaucoma patients. COVs for SD-OCT ranged from 0.3–1% in non-glaucomas and from 0.9–2.3% in glaucomatous eyes. COVs were influenced by various factors. In the glaucoma group, COVs were significantly higher (p < 0.001) compared to the non-glaucoma group. COVs increased by a mean of 5.1% when TD-OCT was used instead of SD-OCT (p < 0.001).ConclusionsSD-OCT RNFL thickness measurements in healthy volunteers and glaucoma patients showed good intra- and inter-observer repeatability. Especially in glaucomatous eyes, repeatability of SD-OCT was superior to TD-OCT.

Repeatability of intraocular pressure measurements with Icare PRO rebound, Tono-Pen AVIA, and Goldmann tonometers in sitting and reclining positions

BackgroundIcare PRO (ICP) is a new Rebound tonometer that is able to measure intraocular pressure (IOP) in both sitting and reclining positions. In this study, the gold standard Goldmann tonometer (GAT) was compared to ICP and Tono-Pen AVIA (TPA). Hypothesis was that repeatability of GAT is superior to ICP and TPA.Methods36 eyes of 36 healthy caucasian individuals, 13 male and 26 females, 17 right and 19 left eyes have been included in this prospective, randomized, cross-sectional study. The study was conducted at a single site (Dept. of Ophthalmology, UniversityHospital Zurich, Switzerland). Primary outcome measures were Intraclass correlation coefficients (ICC) and coefficients of variation (COV) and test-retest repeatability as visualized by Bland-Altman analysis. Secondary outcome measures were IOP in sitting (GAT, ICP and TPA) and in reclining (ICP and TPA) position.ResultsMean IOP measured by GAT was 14.9±3.5 mmHg. Mean IOP measured by ICP was 15.6±3.1 mmHg (with TPA 14.8±2.7 mmHg) in sitting and 16.5±3.5 mmHg (with TPA 17.0±3.0 mmHg) in reclining positions. COVs ranged from 2.9% (GAT) to 6.9% (ICP reclining) and ICCs from 0.819 (ICP reclining) to 0.972 (GAT).ConclusionsRepeatability is good with all three devices. GAT has higher repeatability compared to the two tested hand-held devices with lowest COVs and highest ICCs. IOP was higher in the reclining compared to the sitting position.Trial registrationThe study was registered to the Clinical Trials Register of the US National Institute of Health, NCT01325324.

[One-year results after combined cataract surgery and excimer laser trabeculotomy for elevated intraocular pressure].

BACKGROUND Glaucoma is one of the most common reasons for blindness. Usually an elevated resistance to aqueous outflow is the reason, while aqueous humor production is still normal. Medical reduction of intraocular pressure (IOP) is the first-line therapy in most cases. The gold standard of surgical treatment is trabeculectomy (TE). But TE has a lot of postoperative complications. Therefore we prefer the combined procedure of cataract extraction plus excimer laser trabeculotomy (phaco-ELT) for a selected group of glaucoma patients. Indications are cataract together with moderately elevated IOP without medical therapy or a moderate cataract together with elevated IOP under medical therapy. PATIENTS AND METHODS During ELT, 10 pores were created over 90° of the anterior chamber angle; 28 eyes of 28 patients (10 men and 18 women) were reexamined 12 months ± 2 weeks after combined phaco-ELT. Four patients were excluded because of IOP-lowering surgery during the follow-up. IOP, best corrected visual acuity, slit lamp biomicroscopy as well as glaucoma medication history (antiglaucoma drugs, AGD) were recorded. RESULTS The mean age was 74.33±11.81 years. The diagnosis was primary open-angle glaucoma in 9 eyes, pseudoexfoliative glaucoma in 15 eyes, ocular hypertension in 3 eyes, and 1 post-traumatic secondary glaucoma. On average, phaco-ELT could reduce the IOP by 8.79±5.28 mmHg (-34.70%, p<0.001). AGD could be reduced by 0.79±1.50 (-62.70%, p=0.017) at the same time. CONCLUSION The ELT is easy to perform at the end of cataract surgery. Duration of surgery is only prolonged by 2 to 3 minutes. We found an average IOP reduction of 8.79 mmHg (-34.70%) and an average reduction of 0.79 AGD. It is known that the effect of IOP reduction is constant over time unlike argon or selective laser trabeculoplasty. If needed later on, filtering surgery is not compromised because there is no conjunctival touch during ELT and therefore no scarring of the conjunctiva. For a selected collective of glaucoma patients this procedure could be a good way to avoid trabeculectomy.

Evaluation of filtering blebs using the ‘Wuerzburg bleb classification score’ compared to clinical findings

BackgroundTo determine the agreement between intraocular pressure and the ‘Wuerzburg bleb classification score’, as well as between single items of the score and intraocular pressure. Interobserver variability was analyzed.Methods57 post-trabeculectomy eyes were included. Colour photographs were used to score the filtering bleb in accordance to the Wuerzburg bleb classification score by two different examiners. At the same visit, clinical data such as intraocular pressure, best corrected visual acuity, slit lamp biomicroscopy and medical history were obtained by another examiner.ResultsAfter trabeculectomy, 42 out of 57 eyes (73.7%) reached the target pressure (≤21mmHg, and intraocular pressure reduction of at least 20%, without antiglaucoma medication, and without any additional intervention). Fair agreement was found between intraocular pressure and Wuerzburg bleb classification score ≥8 points and ≥7 points (kappa 0.24 and 0.27, respectively). Analyzing the subgroups of the morphological criteria, best agreement was found between occurrence of microcysts and target intraocular pressure (к 0.22 – 0.34).ConclusionsEvaluating filtering blebs after trabeculectomy by using the Wuerzburg bleb classification score is a good technique for predicting intraocular pressure control in eyes attaining a minimum score of seven points. The presence of microcysts on the filtering bleb predicts that the eye is likely to attain target pressure.

Cataract Surgery combined with excimer laser trabeculotomy to lower intraocular pressure: effectiveness dependent on preoperative IOP

BackgroundCataract surgery combined with excimer laser trabeculotomy (phaco-ELT) can reduce intraocular pressure (IOP). The aim of this study was to evaluate the effect of phaco-ELT on IOP in patients as a function of preoperative IOP.MethodsPatients with open-angle glacuoma or ocular hypertension who received phaco-ELT between 01/2008 and 10/2009 were included. Patients were assigned based on preoperative IOP either to the study group (≤21 mmHg) or control group (>21 mmHg) in this IRB-approved, prospective, consecutive case series. Visual Acuity, IOP, and number of anti-glaucoma drugs (AGD) were recorded at baseline and 12 months after phaco-ELT. Any postoperative complications were also recorded.Results64 eyes of 64 patients (76.5 ± 9.4 years) were included. Baseline IOP was 19.8 ± 5.3 mmHg (AGD 2.4 ± 1.1) for all eyes, 16.5 ± 2.9 mmHg (AGD 2.5 ± 1.0) for the study group, and 25.8 ± 2.9 mmHg (AGD 2.2 ± 1.4) for the control group. Across the two groups, IOP was reduced by 4.5 ± 5.9 mmHg (-23.0%, p < 0.001) and AGD by 0.9 ± 1.5 (-38.9%, p < 0.001). For the study group IOP was reduced by 1.9 ± 4.4 mmHg (-11. 5 %, p = 0.012) and AGD by 1.1 ± 1.4 (-42.9%, p < 0.001), and for the control group by 9.5 ± 5.4 mmHg (-36.6%, p < 0.001) and AGD by 0.7 ± 1.6 (-29.5%, p = 0.085). There were no serious postoperative complications such as endophthalmitis, significant hyphema, or a severe fibrinous reaction of the anterior chamber.ConclusionsIOP remained significantly reduced from baseline 12 months after phaco-ELT regardless of preoperative IOP levels, with no major complications. The IOP reduction remained constant over the entire follow-up. Hence, phaco-ELT can be considered in glaucoma and ocular hypertensive patients whenever cataract surgery is performed, in order to further reduce IOP or to reduce the requirement for IOP-reducing medications.

Selective Laser Trabeculoplasty Following Failed Combined Phacoemulsification Cataract Extraction and Ab Interno Trabeculectomy

PURPOSE To assess the effect of selective laser trabeculoplasty (SLT) following failed phacoemulsification cataract extraction combined with ab interno trabeculectomy (AIT) using the Trabectome (phaco-trabectome). DESIGN Randomized, interventional case series. METHODS Retrospectively, the medical records of patients who underwent SLT between March 2010 and July 2012 by 1 surgeon at a single center after a failed phaco-AIT were evaluated. Inclusion criteria were age ≥18 years with no upper limit and prior failed phaco-AIT attributable to glaucoma progression. Exclusion criterion was performance of any additional glaucoma procedure with influence on intraocular pressure (IOP) during follow-up and a follow-up after surgery of <3 months. Success was defined by reduction of IOP of >3 mm Hg and 20% and number of antiglaucoma medications equal to or less than baseline. Main outcome measures were IOP, antiglaucoma medications, time to failure, and Kaplan-Meier survival curve. RESULTS Fourteen eyes of 13 subjects were included. Mean follow-up after SLT was 12.9 ± 8.7 months. Total laser energy was 59.5 ± 8.7 mJ. Baseline IOP was 17.9 ± 3.3 mm Hg and number of antiglaucoma medications at baseline was 2.0 ± 1.0. All SLT procedures failed. Median time to failure after SLT was 3.6 ± 0.8 (range 2.1-5.1) months. Number of antiglaucoma medications did not change. CONCLUSIONS In eyes in which the IOP was no longer controlled following phaco-trabectome, SLT had a limited duration of significant IOP-lowering effect. Other alternatives, such as incisional filtration surgery, should be considered following failed phaco-trabectome.

1-Jahres-Ergebnisse nach kombinierter Kataraktoperation und Excimer-Laser-Trabekulotomie bei erhöhtem Intraokulardruck

BACKGROUND Glaucoma is one of the most common reasons for blindness. Usually an elevated resistance to aqueous outflow is the reason, while aqueous humor production is still normal. Medical reduction of intraocular pressure (IOP) is the first-line therapy in most cases. The gold standard of surgical treatment is trabeculectomy (TE). But TE has a lot of postoperative complications. Therefore we prefer the combined procedure of cataract extraction plus excimer laser trabeculotomy (phaco-ELT) for a selected group of glaucoma patients. Indications are cataract together with moderately elevated IOP without medical therapy or a moderate cataract together with elevated IOP under medical therapy. PATIENTS AND METHODS During ELT, 10 pores were created over 90° of the anterior chamber angle; 28 eyes of 28 patients (10 men and 18 women) were reexamined 12 months ± 2 weeks after combined phaco-ELT. Four patients were excluded because of IOP-lowering surgery during the follow-up. IOP, best corrected visual acuity, slit lamp biomicroscopy as well as glaucoma medication history (antiglaucoma drugs, AGD) were recorded. RESULTS The mean age was 74.33±11.81 years. The diagnosis was primary open-angle glaucoma in 9 eyes, pseudoexfoliative glaucoma in 15 eyes, ocular hypertension in 3 eyes, and 1 post-traumatic secondary glaucoma. On average, phaco-ELT could reduce the IOP by 8.79±5.28 mmHg (-34.70%, p<0.001). AGD could be reduced by 0.79±1.50 (-62.70%, p=0.017) at the same time. CONCLUSION The ELT is easy to perform at the end of cataract surgery. Duration of surgery is only prolonged by 2 to 3 minutes. We found an average IOP reduction of 8.79 mmHg (-34.70%) and an average reduction of 0.79 AGD. It is known that the effect of IOP reduction is constant over time unlike argon or selective laser trabeculoplasty. If needed later on, filtering surgery is not compromised because there is no conjunctival touch during ELT and therefore no scarring of the conjunctiva. For a selected collective of glaucoma patients this procedure could be a good way to avoid trabeculectomy.

Retinal astrocytomas: long-term follow-up

BACKGROUND Retinal astrocytomas are exceedingly rare benign tumours of the retina. Their occurrence can be solitary or multiple, uni- or bilateral, isolated or in association with a phakomatosis such as tuberous sclerosis or neurofibromatosis type 1. PATIENTS AND METHODS We report the long-term follow-up in three patients with retinal astrocytomas. RESULTS Over many years of follow-up all astrocytomas showed very little progression and no deterioration of visual function. Subtle changes occurred inside the lesions. CONCLUSIONS Even after long-term follow-up the natural course of retinal astrocytic hamartomas seems to be favourable, with visual loss and significant growth being unlikely to occur. A thorough ophthalmological and general evaluation, in order to rule out an underlying systemic disease and to document the ocular status, are needed initially. Thereafter eye examinations can be scheduled in long intervals.

Posterior Pole Asymmetry Analysis with Optical Coherence Tomography

BACKGROUND The aim of this study was to evaluate the reproducibility of the posterior pole asymmetry analysis (PPAA) in glaucomatous eyes and healthy controls in comparison to retinal nerve fiber layer measurements (RNFL) with spectral domain optical coherence tomography (SD-OCT). PATIENTS AND METHODS Prospectively, in a single session by one operator, three measurements were taken of the retinal thickness with the PPAA and three measurements of the RNFL with the eye-tracker function of the Heidelberg Spectralis SD-OCT. RESULTS The mean intraclass correlation coefficient (ICC) and lower confidence intervals (in parentheses) for PPAA were 0.98 (0.96) in both healthy (36 eyes) and glaucomatous eyes (26 eyes). Global coefficients of variation (COVs) were between 0.0 and 1.1% in healthy controls and between 0.0 and 1.9% in glaucoma eyes. Global ICCs for RNFL were 0.98 (0.96) in healthy controls and 0.98 (0.97) in glaucoma eyes and global COVs were between 0.0 and 6.8% in healthy controls and between 0.0 and 3.0% in glaucoma eyes. CONCLUSION Reproducibility of the PPAA was good and exceeds that of established RNFL measurements. Thus, PPAA is an additional useful tool in management of glaucoma.