Philip Enders

One-year outcome after Descemet membrane endothelial keratoplasty (DMEK) comparing sulfur hexafluoride (SF6) 20% versus 100% air for anterior chamber tamponade

Purpose To investigate 1-year clinical outcome and complication rates following Descemet membrane endothelial keratoplasty (DMEK) with sulfur hexafluoride 20% (SF620%) anterior chamber tamponade compared with conventionally used 100% air for primary graft attachment during DMEK surgery. Methods Records of 1112 consecutive DMEKs were reviewed retrospectively and grouped by anterior chamber tamponade used during DMEK surgery (SF620% vs 100% air). Outcome measures included intraocular pressure (IOP), best spectacle-corrected visual acuity (BSCVA), endothelial cell density (ECD) and central corneal thickness (CCT) at 1, 3, 6 and 12 months after DMEK surgery. Complication rates were assessed, including intraoperative and postoperative complications, and graft detachment rate requiring rebubbling. Results A total of 854 cases were included in this study. In 105 cases (12.3%), DMEK was performed with SF620%, and in 749 cases (87.7%) 100% air was used for anterior chamber tamponade. Outcome results for IOP, BSCVA, ECD and CCT at all follow-up time points were comparable for both anterior chamber tamponade groups without statistical significant differences (p≥0.05), but graft detachment rate requiring rebubbling was significantly lower in the SF620% group (p<0.001). Conclusion Whereas SF620% anterior chamber tamponade does not seem to negatively affect the clinical outcome of DMEK surgery within the first postoperative year, use of SF620% significantly reduces the rate of rebubblings.

Neuroretinal rim in non-glaucomatous large optic nerve heads: a comparison of confocal scanning laser tomography and spectral domain optical coherence tomography

Background/aims To compare margin-based rim area measurements from confocal scanning laser tomography (CSLT) with Bruchs membrane opening (BMO)-based measurements from spectral domain optical coherence tomography (SD-OCT) by analysis of a group of non-glaucomatous eyes with large optic discs, so-called macrodiscs (disc size >2.45 mm2 in CSLT). Objective is to create a reference base for large optic nerve heads in SD-OCT diagnostics. Methods 102 eyes received CSLT and SD-OCT measurements and clinical examination on the same day. Visual field testing confirmed absence of glaucomatous defects. Statistical and correlation analysis was performed for rim area by CSLT as well as retinal nerve fibre layer thickness (RNFLT) and BMO minimal rim width (BMO-MRW) by SD-OCT. Results Mean disc size in CSLT was 2.98±0.4 mm2 (range 2.45–4.23), mean rim area of 1.55±0.4 mm2. BMO area was 2.51±0.33 mm2 (range 1.61–3.51), mean global RNFLT was 79.55±17.2 μm, mean global BMO-MRW was 234.84±48.3 μm. Correlation of BMO-MRW to global RNFLT was stronger (r=0.60, p<10−5) than correlation of CSLT rim area to global RNFLT (r=0.26, p=0.24). BMO-MRW and CSLT rim area correlated with r=0.59 (p<10−5). BMO-MRW and RNFLT significantly decreased with increasing age (p<0.001). Annual loss of BMO-MRW was 0.8 μm/year (R2=0.14, p<0.001), loss of RNFLT was 0.27 μm/year (R2=0.17, p=0.001). Conclusions In large optic discs, BMO-MRW is thinner compared with normal-sized discs and correlates better than CSLT parameters with the RNFLT. An age-depended loss of BMO-MRW needs to be taken into account in evaluation of the neuroretinal rim.

Novel Bruch's Membrane Opening Minimum Rim Area Equalizes Disc Size Dependency and Offers High Diagnostic Power for Glaucoma

Purpose The purpose of this study was to assess the diagnostic power of the novel two-dimensional parameter Bruchs membrane opening minimal rim area (BMO-MRA) in spectral-domain optical coherence tomography (SD-OCT) for detection of glaucoma compared to minimal rim width (BMO-MRW) and retinal nerve fiber layer (RNFL) thickness in large and small optic discs. Methods In this case-control, cross-sectional study, 207 eyes of 207 participants, including 89 controls and 97 patients with glaucoma and 21 with ocular hypertension (OHT), with a disc size <1.63 mm2 or >2.43 mm2 underwent SD-OCT, confocal laser scanning tomography (CSLT), visual field testing, and clinical examination. Bruchs membrane opening-MRA BMO-MRW, RNFL thickness of SD-OCT and disc margin rim area (DM-RA) of CSLT were evaluated and analyzed for diagnostic power to detect glaucoma. Results In healthy eyes with macrodiscs, mean BMO-MRW of 243.14 ± 43.12 μm was significantly smaller than BMO-MRW in microdiscs (338.97 ± 69.39; P < 0.001). Bruchs membrane opening-MRA was comparable between disc size groups with 1.22 ± 0.25 mm2 for macrodiscs and 1.26 ± 0.27 mm2 for microdiscs (P = 0.51), as was RNFL thickness (82.69 ± 15.76 μm versus 78.53 ± 11.01 μm, respectively; P = 0.28). Perimetric mean deviation was -8.7 ± 6.3 dB in glaucoma and -0.6 ± 1.60 dB in OHT patients. Correlation of BMO-MRA and visual field function was rho (ρ) = 0.70 (P < 0.001). Diagnostic power to differentiate glaucoma patients was highest for BMO-MRA. Partial area under the curve (pAUC) for BMO-MRA was 0.14 for specificity between 0.8 and 1.0, exceeding pAUCs of BMO-MRW (P < 0.001), RNFL thickness (P = 0.03), and DM-RA (P = 0.01). Conclusions Bruchs membrane opening-based minimum rim area measurements offer advantages compared to one-dimensional parameters assessing neuroretinal rim by SD-OCT. In nonglaucomatous eyes, BMO-MRA values seem comparable for the full range of disc sizes. Bruchs membrane opening-MRA surpasses other parameters in diagnostic power for glaucoma.

The use of Bruch's membrane opening-based optical coherence tomography of the optic nerve head for glaucoma detection in microdiscs

Purpose To assess the performance of Bruchs membrane opening (BMO)-based spectral domain optical coherence tomography (SD-OCT) of the optic nerve head for glaucoma detection in microdiscs in comparison with confocal scanning laser tomography (CSLT). Design Retrospective cohort study. Methods 82 eyes of 82 patients with disc size <1.63 mm2 underwent SD-OCT and CSLT measurements, visual field testing and clinical examination. BMO-based minimal rim width (BMO-MRW), retinal nerve fibre layer thickness (RNFLT) in SD-OCT and rim area measured in CSLT were compared and correlated with visual field defects. Results 51 patients with glaucoma, 11 patients with ocular hypertension (OHT) and 20 healthy controls had a mean disc area of 1.36±0.19 mm2 in CSLT, and BMO area was 1.45±0.22 mm2 (r=0.17; p=0.12). In patients with glaucoma, visual field mean defect was −7.5±6.7 dB. Global BMO-MRW correlated better with visual field function (Spearmans r=0.65; p<0.001) than RNFLT (r=0.58; p≤0.001) and CSLT rim area (r=0.47; p=0.004). BMO-MRW significantly deteriorated with progressive visual field loss (p<0.001). In receiver operating characteristic analysis, sensitivity of BMO-MRW was 68.6% at 95% specificity (area under curve (AUC)=0.87), similar to sensitivity of RNFLT (66.4%; AUC=0.81). Performance of CSLT rim area was significantly worse (AUC=0.70, p=0.008). In healthy controls, mean BMO-MRW was 344.3±64.1 µm, mean RNFLT 78.0±11.3 µm and CSLT mean rim area 1.07±0.18 mm2. Conclusions In small optic discs, BMO-MRW and peripapillary RNFLT (OCT) have similar sensitivity to discriminate patients with glaucoma from normal controls; both exceed CSLT rim area in diagnostic power. In glaucomatous patients, BMO-MRW correlates strongest with visual field function.

Long-term alterations of systemic vascular endothelial growth factor levels in patients treated with ranibizumab for age-related macular degeneration.

Purpose: To analyze long-term changes of systemic vascular endothelial growth factor (VEGF) levels in patients treated with ranibizumab for neovascular age-related macular degeneration. Methods: Sixty-one patients with neovascular age-related macular degeneration and 68 age-matched controls were included in the study. Patients were treated with ranibizumab on a pro re nata regimen. Plasma samples were collected before initiation of treatment and after 1 year (30 patients) or 2 years (31 patients) of treatment. Vascular endothelial growth factor was measured by Luminex microbead analysis. Results: At baseline, patients with neovascular age-related macular degeneration and controls did not differ significantly in VEGF levels (P = 0.062). There was a significant decline in systemic VEGF levels of 39.5% after 1 year (34.2 ± 17.2 pg/mL to 20.7 ± 14.0 pg/mL; P = 7.50 × 10−5) and of 46.7% after 2 years (40.4 ± 24.1 pg/mL to 21.5 ± 23.3 pg/mL; P = 2.48 × 10−4) of treatment. Patients with persistent activity of choroidal neovascularization showed a significantly smaller decrease of plasma VEGF levels than patients with dry intervals despite the higher number of injections (P = 0.048). Conclusion: In addition to immediate effects limited to days if not hours, ranibizumab also leads to long-term alterations of systemic VEGF to subnormal levels. Patients with persistent choroidal neovascularization activity showed a less pronounced VEGF decrease. Therefore, VEGF levels might be a useful marker for treatment response.

Intraday Repeatability of Bruch's Membrane Opening-Based Neuroretinal Rim Measurements

Purpose To assess possible intraday variability in Bruchs membrane opening-based (BMO) assessment of neuroretinal rim by spectral-domain optical coherence tomography (SD-OCT) of the optic nerve head (ONH) as well as to evaluate its independence from intraindividual IOP changes. Methods In this noninterventional, prospective cohort study, 51 consecutively enrolled patients with glaucoma or ocular hypertension underwent standardized SD-OCT of the ONH and IOP assessment at two different time points with a time gap of 5 hours on the same day. Random effects models, intraclass correlation coefficients (ICC) and Bland-Altman plots were used to analyze repeatability of BMO minimum rim width (BMO-MRW) and area (BMO-MRA) and peripapillary retinal nerve fiber layer (RNFL) thickness measurements. Results Mean BMO area was 1.86 ± 0.30 mm2. At baseline, mean BMO-MRW was 206.46 ± 0.86 μm, mean BMO-MRA was 0.89 ± 0.34 mm2, and mean RNFL thickness was 71.61 ± 0.20 μm. Within intraindividual measurements, mean difference was 2.95 μm or 1.76% for BMO-MRW, 0.02 mm2 or 2.68% for BMO-MRA, and 1.18 μm or 1.89% for RNFL thickness. Comparing time points, η2 was 0.001 (P = 0.757) for RNFL thickness, 0.043 (P = 0.01) for BMO-MRA, and 0.07 (P = 0.06) for BMO-MRW. Intraclass correlation coefficients were greater than 0.994, respectively. Variability of morphometric parameters did not correlate to intraindividual IOP fluctuations. Conclusions Assessment of BMO-MRW by SD-OCT shows high intraday repeatability, which is comparable to the parameter RNFL thickness. Variability seems not to be driven by typical moderate intraday fluctuations of IOP. The two-dimensional parameter BMO-MRA incorporates a fairly higher intraindividual variability.

Corneal Densitometry for Quantification of Corneal Deposits in Monoclonal Gammopathies

Purpose: To assess the capability of Scheimpflug-based densitometry of the cornea to quantify light chain deposits in patients with active monoclonal gammopathies. Methods: This is a case–control study in which data from a leading tertiary university center in myeloma care were analyzed. Ten eyes of 5 patients with monoclonal gammopathy and 26 eyes of 13 healthy controls undergoing clinical evaluation and Scheimpflug-based measurements were included in the study. The main outcome measures were densitometry data of the 4 corneal layers—anterior layer (AL), central layer (CL), posterior layer, and total layer (TL)—in 4 different annuli (central annular zone 0–2 mm, intermediate annular zone 2–6 mm, peripheral annular zone 6–10 mm, and total annular zone 0–12 mm). Results: In 8 eyes of 4 patients with IgG-based gammopathy, corneal light backscatter was highest in the AL and decreased with increasing corneal depth. The peripheral annular zone showed a higher densitometry value compared with the corneal center. Compared with healthy controls, the AL (P < 0.001), the CL (P < 0.001), and the TL (P < 0.001) had significantly higher corneal light backscatter in patients with gammopathy in the total and the peripheral annular zones. In one patient with predominantly IgA-based disease, corneal light backscatter was not elevated. Conclusions: Scheimpflug-based densitometry of the cornea is able to quantify opacification by immunoglobulin G light chain deposits in monoclonal gammopathies. This noninvasive technique can complement presently used in vivo confocal microscopy and corneal photography to objectivize corneal changes. Densitometry might allow monitoring of corneal immunoglobulin deposits in follow-up examinations.

Spectral-Domain Optical Coherence Tomography–Derived Characteristics of Bruch Membrane Opening in a Young Adult Australian Population

WEHAVE READ THE ARTICLE ENTITLED ‘‘SPECTRAL-DOMAIN optical coherence tomography–derived characteristics of Bruch’s membrane opening (BMO) in a young adult Australian population,’’ by Sanfilippo and associates, with great interest. The authors investigated characteristics of BMO of the optic nerve head (ONH) in 1344 predominantly white young adults in Australia by spectral-domain optical coherence tomography (SDOCT). This relatively new technique for evaluation of the ONH in glaucoma and other neurodegenerative diseases is gaining importance in the clinical standard of care. In 2688 eyes, Sanfilippo and associates found a disc area of 1.926 0.50 mm, ranging from 0.86 mm to 4.17 mm in confocal scanning laser tomography (CSLT, also referred to as Heidelberg Retina Tomograph, HRT) and a BMO area in SDOCT of 1.77 6 0.38 mm, ranging from 0.94 mm to 4.06 mm. The size of the optic disc plays an important role in the clinical evaluation, especially in large discs, also called macrodiscs, where the neuroretinal rim might seem thinned even in healthy adults. CSLT is often used to assess the disc area. Current evaluation software of confocal scanning laser tomography comprises a range for normal disc size from 1.63 mm to 2.43 mm, whereas according to the authors, multiple studies of white subjects reported a mean disc size of 2.5 mm (range, 2.1– 2.8 mm). Supporting the importance of the results of Sanfilippo and associates, we would like to highlight the difference in area measurements between CSLT and SDOCT in larger optic discs. In 102 eyes with macrodiscs (disc area >2.43 mm in CSLT), we found a mean disc area of 2.98 6 0.4 mm (range, 2.45–4.23 mm) in CSLT and a mean BMO area of 2.51 6 0.33 mm (1.61–3.51 mm), correlating with r 1⁄4 0.72 (P < .001). In very small optic discs (microdiscs, area <1.63 mm in CSLT), mean disc area in CSLT was 1.37 6 0.19 mm

Evaluation of two-dimensional Bruch's membrane opening minimum rim area for glaucoma diagnostics in a large patient cohort

To characterize the two‐dimensional parameter Bruchs membrane opening minimum rim area (BMO‐MRA) in spectral domain optical coherence tomography (SD‐OCT) of the optic nerve head (ONH) compared to minimum rim width (BMO‐MRW) and retinal nerve fibre layer (RNFL) thickness in a large patient cohort.

Optimization Strategies for Bruch’s Membrane Opening Minimum Rim Area Calculation: Sequential versus Simultaneous Minimization

To compare a simultaneously optimized continuous minimum rim surface parameter between Bruch’s membrane opening (BMO) and the internal limiting membrane to the standard sequential minimization used for calculating the BMO minimum rim area in spectral domain optical coherence tomography (SD-OCT). In this case-control, cross-sectional study, 704 eyes of 445 participants underwent SD-OCT of the optic nerve head (ONH), visual field testing, and clinical examination. Globally and clock-hour sector-wise optimized BMO-based minimum rim area was calculated independently. Outcome parameters included BMO-globally optimized minimum rim area (BMO-gMRA) and sector-wise optimized BMO-minimum rim area (BMO-MRA). BMO area was 1.89 ± 0.05 mm2. Mean global BMO-MRA was 0.97 ± 0.34 mm2, mean global BMO-gMRA was 1.01 ± 0.36 mm2. Both parameters correlated with r = 0.995 (P < 0.001); mean difference was 0.04 mm2 (P < 0.001). In all sectors, parameters differed by 3.0–4.2%. In receiver operating characteristics, the calculated area under the curve (AUC) to differentiate glaucoma was 0.873 for BMO-MRA, compared to 0.866 for BMO-gMRA (P = 0.004). Among ONH sectors, the temporal inferior location showed the highest AUC. Optimization strategies to calculate BMO-based minimum rim area led to significantly different results. Imposing an additional adjacency constraint within calculation of BMO-MRA does not improve diagnostic power. Global and temporal inferior BMO-MRA performed best in differentiating glaucoma patients.