Tapping into non-English-language science for the conservation of global biodiversity.

The widely held assumption that any important scientific information would be available in English underlies the underuse of non-English-language science across disciplines. However, non-English-language science is expected to bring unique and valuable scientific information, especially in disciplines where the evidence is patchy, and for emergent issues where synthesising available evidence is an urgent challenge. Yet such contribution of non-English-language science to scientific communities and the application of science is rarely quantified. Here, we show that non-English-language studies provide crucial evidence for informing global biodiversity conservation. By screening 419,679 peer-reviewed papers in 16 languages, we identified 1,234 non-English-language studies providing evidence on the effectiveness of biodiversity conservation interventions, compared to 4,412 English-language studies identified with the same criteria. Relevant non-English-language studies are being published at an increasing rate in 6 out of the 12 languages where there were a sufficient number of relevant studies. Incorporating non-English-language studies can expand the geographical coverage (i.e., the number of 2° × 2° grid cells with relevant studies) of English-language evidence by 12% to 25%, especially in biodiverse regions, and taxonomic coverage (i.e., the number of species covered by the relevant studies) by 5% to 32%, although they do tend to be based on less robust study designs. Our results show that synthesising non-English-language studies is key to overcoming the widespread lack of local, context-dependent evidence and facilitating evidence-based conservation globally. We urge wider disciplines to rigorously reassess the untapped potential of non-English-language science in informing decisions to address other global challenges. Please see the Supporting information files for Alternative Language Abstracts.

Proton-gated coincidence detection is a common feature of GPCR signaling.

The evolutionary expansion of G protein-coupled receptors (GPCRs) has produced a rich diversity of transmembrane sensors for many physical and chemical signals. In humans alone, over 800 GPCRs detect stimuli such as light, hormones, and metabolites to guide cellular decision-making primarily using intracellular G protein signaling networks. This diversity is further enriched by GPCRs that function as molecular sensors capable of discerning multiple inputs to transduce cues encoded in complex, context-dependent signals. Here, we show that many GPCRs are coincidence detectors that couple proton (H+) binding to GPCR signaling. Using a panel of 28 receptors covering 280 individual GPCR-Gα coupling combinations, we show that H+ gating both positively and negatively modulates GPCR signaling. Notably, these observations extend to all modes of GPCR pharmacology including ligand efficacy, potency, and cooperativity. Additionally, we show that GPCR antagonism and constitutive activity are regulated by H+ gating and report the discovery of an acid sensor, the adenosine A2a receptor, which can be activated solely by acidic pH. Together, these findings establish a paradigm for GPCR signaling, biology, and pharmacology applicable to acidified microenvironments such as endosomes, synapses, tumors, and ischemic vasculature.

Epidemiology of Field of Vision Disorders (eFOVID) study, Western Australia, 1988-2022. Report 1: Data collection and aggregation protocol.

BACKGROUND: Computerised static visual field testing using dedicated machines such as the Humphrey Field Analyzer (HFA) can assess and track changes in visual field sensitivity. The use of retrospective visual field databases is a novel undertaking, with no studies published utilising large scale population-level data. This study phase developed a method to extract HFA data into a large standardised population-based database including point sensitivity data with additional derived variables. METHODS: Retrospective, longitudinal, population study of visual field data from people who attended an ophthalmology service and had a HFA field test, in Western Australia, between 1988 and 2022. Raw test data included patient demographic fields, sensitivity readings and test parameters. Calculated fields included reliability scores, and a novel combined reliability score. RESULTS: There were 606 230 tests for 92 215 study individuals, from 22 ophthalmology practices in metropolitan Perth and three public hospital eye clinics, representing around 85% of the field tests performed by ophthalmologists each year. Raw sensitivity values were available for all tests, and additional descriptors were available for most tests (97.5%-100% of tests) with the exception of data variables retired by the manufacturer. CONCLUSIONS: Visual field data from 606 230 tests were collated into a single dataset, which is highly representative over a long period of time, for a defined population. This dataset has been linked to other administrative datasets to allow for epidemiological investigation of field of vision disorders.

Topographic distribution and phenotypic heterogeneity of Schlemm's canal endothelium in human donor eyes.

Endothelium phenotype is known to be closely associated with flow shear stress. This study is to determine the topographic distribution of endothelial cells and the phenotype of different quadrants and regions of Schlemm's canal using human donor eyes. This study infers differences in flow dynamics based on cell shape and intracellular structure. The Schlemm's canal from 15 human donor eyes were either perfusion labelled using silver stain or dissected for float labeling with Phalloidin to enable visualization of endothelial cell border and intracellular structure. Data were acquired for endothelial cells from the outer and inner wall of Schlemm's canal and grouped according to quadrant of origin. Measurements included endothelial cell length, width, area, and aspect ratio and compared between quadrants. Endothelial cells are mostly spindle-shape and the cell size on the outer wall are larger and longer than those from the inner wall. Significant differences in endothelial cell size and shape were seen in different quadrants. The endothelial cells have varied shapes and orientations close to large ostia in the outer wall and remarkably long endothelial cells were found in the walls of collector channels. F-actin aggregation was found at all endothelial cell borders, and inside some of the endothelial cytoplasm. The presence of various spindle shapes, significant phenotype heterogeneity and F-actin aggregation of endothelial cells indicates aqueous humor flow likely creates variations in shear stress within Schlemm's canal. Further investigation of the relationship between the phenotype heterogeneity and hydrodynamics of aqueous flow may help us understand the mechanisms of outflow resistance changes in glaucoma.

Endothelial contraction of retinal veins.

We have previously reported that porcine retinal veins can be contracted by vasoactive factors such as endothelin-1, but it is still unknown which cells play the major role in such contraction responses. This study seeks to confirm whether retinal vein endothelial cells play a significant role in the endothelin-1 induced contraction of porcine retinal veins. This is a novel study which provides confirmation of the endothelial cells' ability to contract retinal veins using a live vessel preparation. Retinal veins were isolated from porcine retina and cannulated for perfusion. The vessels were exposed to extraluminal delivery of endothelin-1 (10-8 M) and change in vessel diameter recorded automatically every 2 s. A phase contrast objective lens was also used to capture images of the endothelial cell morphometries. The length, width, area, and perimeter were assessed. In addition, vein histology and immuno-labeling for contractile proteins was performed. With 10-8 M endothelin-1 contractions to 63.6% of baseline were seen. The polygonal shape of the endothelial cells under normal tone became spindle-like after contraction. The area, width, perimeter and length were significantly reduced by 54.8%, 48.1%, 28.5% and 10.5% respectively. Three contractile proteins, myosin, calponin and alpha-SMA were found in retinal vein endothelial cells. Retinal vein endothelial cells contain contractile proteins and can be contracted by endothelin-1 administration. Such contractile capability may be important in regulating retinal perfusion but could also be a factor in the pathogenesis of retinal vascular diseases such as retinal vein occlusion. As far as we are aware, this is the first study on living isolated veins to confirm that endothelial cells contribute to the endothelin-1 induced contraction.

Complete resolution of focal-on-diffuse myocardial activity pattern on FDG PET-CT by prolonging the dietary preparation protocol in cardiac sarcoidosis.

Patient preparation is crucial for reliable interpretation of cardiac inflammation FDG PET. We share our experience of improved reporting confidence and propose a simple approach of prolonging preparation (from 24 to 48 hours) with the high-fat, no-carbohydrate, and protein-permitted diet followed by fasting in cardiac sarcoidosis in cases with diffuse or focal-on-diffuse myocardial FDG uptake.

Outcomes of 45 µm gelatin stent surgery over 24-month follow-up.

BACKGROUND: The main objectives of this study were to determine whether known risk factors for trabeculectomy failure similarly influence gelatin stent outcomes and to identify surgical factors which may optimise success. METHODS: A retrospective, observational study was conducted at a single centre in Perth, Western Australia over 24 months. Two-hundred and sixty-two eyes of 207 patients underwent XEN-45 stent surgery with various forms of glaucoma. Surgical and postoperative data on subjects undergoing XEN-45 stent surgery was collated. Intraocular pressure (IOP) reduction success was determined using three criteria: 1; IOP <18 mm Hg, 2: IOP <15 mm Hg and 3: >25% IOP reduction from baseline. Kaplan-Meier, mixed effects Cox Proportional hazard model and Chi-Square test were used to measure survival of functioning stents. RESULTS: The success rates at a maximum of 2 years after surgery by criteria 1, 2 and 3 were 61.3%, 26.2% and 28.9% in primary open angle glaucoma (n = 243), 18.8%, 16.9%, 21.4% in angle closure glaucoma (n = 11), 0%, 0%, 66.7% in congenital glaucoma (n = 5) and 0% in uveitic glaucoma (n = 3). No significant reduction in success was found in those eyes that had prior ocular surgery (all p > 0.07). CONCLUSIONS: Prior cataract or trabeculectomy surgery does not appear to adversely affect gelatin stent outcomes over 2 years follow up. Gelatin stent surgery appears to have less IOP reduction effect compared to trabeculectomy at 2 years.

The evolution and mechanism of GPCR proton sensing.

Of the 800 G protein-coupled receptors (GPCRs) in humans, only three (GPR4, GPR65, and GPR68) regulate signaling in acidified microenvironments by sensing protons (H+). How these receptors have uniquely obtained this ability is unknown. Here, we show these receptors evolved the capability to sense H+ signals by acquiring buried acidic residues. Using our informatics platform pHinder, we identified a triad of buried acidic residues shared by all three receptors, a feature distinct from all other human GPCRs. Phylogenetic analysis shows the triad emerged in GPR65, the immediate ancestor of GPR4 and GPR68. To understand the evolutionary and mechanistic importance of these triad residues, we developed deep variant profiling, a yeast-based technology that utilizes high-throughput CRISPR to build and profile large libraries of GPCR variants. Using deep variant profiling and GPCR assays in HEK293 cells, we assessed the pH-sensing contributions of each triad residue in all three receptors. As predicted by our calculations, most triad mutations had profound effects consistent with direct regulation of receptor pH sensing. In addition, we found that an allosteric modulator of many class A GPCRs, Na+, synergistically regulated pH sensing by maintaining the pKa values of triad residues within the physiologically relevant pH range. As such, we show that all three receptors function as coincidence detectors of H+ and Na+. Taken together, these findings elucidate the molecular evolution and long-sought mechanism of GPR4, GPR65, and GPR68 pH sensing and provide pH-insensitive variants that should be valuable for assessing the therapeutic potential and (patho)physiological importance of GPCR pH sensing.

Effect of left ventricular mechanical dyssynchrony assessed pre-renal transplantation on cardiovascular death post transplantation.

BACKGROUND: SPECT myocardial perfusion imaging (MPI) provides an assessment of LV mechanical dyssynchrony (LVMD) which correlates with CVD outcomes in diverse populations including those awaiting renal transplant (RT). The current study examines the association of LVMD on pre-transplant MPI with long-term CVD mortality post RT. METHODS: We identified consecutive patients who underwent RT at the University of Alabama at Birmingham between 2008 and 2012 from our prospectively collected database. 675 patients in the database underwent MPI and had images amenable for phase analysis. A blinded investigator retrieved the studies and derived LVMD indices including histogram bandwidth (BW), standard deviation (SD), phase peak, phase skewness, and phase kurtosis. The primary outcome was CVD death after RT. RESULTS: The study cohort had a median age of 54 years, 56% were men, 43% had diabetes, and 7% had prior myocardial infarction. Patients were on dialysis for a median of 3.4 years prior to RT and 34% received living donor transplants. During a median follow-up time after RT of 4.7 years (IQR 3.5 to 6.3 years) 59 patients (9%) succumbed to CVD death. Patients with wider BW, wider SD, lower skewness, and lower kurtosis had an increased risk of CVD death. On multivariate adjustment, BW and skewness remained as independent predictors of CVD deaths. CONCLUSIONS: LVMD by phase analysis of gated SPECT MPI is associated with increased risk of CVD death after RT. This association is independent of demographics, comorbidities, and traditional findings on MPI and added incremental prognostic information. Assessment of LVMD should be considered for risk stratification in these patients.

CRISPR-addressable yeast strains with applications in human G protein-coupled receptor profiling and synthetic biology.

Genome stability is essential for engineering cell-based devices and reporter systems. With the advent of CRISPR technology, it is now possible to build such systems by installing the necessary genetic parts directly into an organism's genome. Here, we used this approach to build a set of 10 versatile yeast-based reporter strains for studying human G protein-coupled receptors (GPCRs), the largest class of membrane receptors in humans. These reporter strains contain the necessary genetically encoded parts for studying human GPCR signaling in yeast, as well as four CRISPR-addressable expression cassettes, i.e. landing pads, installed at known safe-harbor sites in the yeast genome. We showcase the utility of these strains in two applications. First, we demonstrate that increasing GPCR expression by incrementally increasing GPCR gene copy number potentiates Gα coupling of the pharmacologically dark receptor GPR68. Second, we used two CRISPR-addressable landing pads for autocrine activation of a GPCR (the somatostatin receptor SSTR5) with its peptide agonist SRIF-14. The utility of these reporter strains can be extended far beyond these select examples to include applications such as nanobody development, mutational analysis, drug discovery, and studies of GPCR chaperoning. Additionally, we present a BY4741 yeast strain created for broad applications in the yeast and synthetic biology communities that contains only the four CRISPR-addressable landing pads. The general utility of these yeast strains provides an inexpensive, scalable, and easy means of installing and expressing genes directly from the yeast genome to build genome-barcoded sensors, reporter systems, and cell-based factories.

Quantitative analysis of astrocyte and axonal density relationships: Glia to neuron ratio in the optic nerve laminar regions.

Astrocytes are critical for the maintenance of retinal ganglion cell (RGC) axonal function and viability, and form a key component of the functional neurovascular unit. Recently, we described the quantitative properties of astrocytes in relation to the capillary distributions in optic nerve laminar regions. Here, we provide a quantitative analysis of astrocytes and RGC axons in longitudinal sections of optic nerve tissue. Histological and immunocytochemical techniques are used to demonstrate the density of astrocytes, RGC axons and glia-neuron ratios across the pre laminar, lamina cribrosa and post laminar compartments of the optic nerve head (ONH). A study of human, pig, horse and rat optic nerves was performed and comparisons are made between species. This study demonstrates that the distribution of astrocytes correlates closely with the density of axonal processes, in accordance with the functional requirement of different regions of the ganglion cell axon. There was a consistency of glia-neuron ratios in the majority of laminar compartments, except for the human and rat prelaminar regions, which demonstrated lower ratios of astrocyte to axonal processes. The distribution of astrocytes may reflect a functional susceptibility to development of disease in the prelaminar region of the optic nerve. Interspecies comparison at the lamina cribrosa showed strikingly consistent glia-neuron ratios. Collectively, our findings suggest there may be a critical ratio of glia to neuron needed to maintain healthy cellular physiology across different laminar compartments of the optic nerve, with particular importance for the health of the lamina cribrosa region. It is possible that, in disease processes, the glia-neuron relationships across the different laminar compartments may be perturbed and this may be relevant for the development of glaucoma. Emerging technologies may further aid our understanding in how the physiology of optic nerve tissue cellular structure may be affected by changes to ONH characteristics and elevated intraocular pressure induced damage. Such findings may also permit the early identification of RGC axonal injury by identifying quantifiable changes in structural tissue architecture when pathophysiological pathways predominate.

Use of trypan blue as an aqueous tracer dye to investigate hypotony where cyclodialysis cleft is suspected.

IMPORTANCE: A new method to help diagnose suspected cyclodialysis clefts. BACKGROUND: To study the use of trypan blue stained aqueous flow patterns in diagnosing causes of hypotony where cyclodialysis clefts were suspected. DESIGN: A case series in a tertiary care centre. PARTICIPANTS: Ten subjects presenting with persistent hypotony and retinal changes. METHODS: Trypan blue was injected into the anterior chamber. MAIN OUTCOME MEASURES: The pattern of dye flow in the anterior chamber was categorized. Intraocular pressure prior to surgery was recorded. RESULTS: All seven subjects with cyclodialysis clefts had a preferential flow to the cleft region. Two hypotonous subjects post trabeculectomy had rapid (5 seconds) and extensive lymphatic staining (6 o'clock hours extent) without visible bleb formation. CONCLUSIONS AND RELEVANCE: Preferential flow of dye to the limbus is a reliable sign of cyclodialysis cleft and helps localize cleft extent. A new cause of hypotony, "lymphatic overdrain," is identified.

Use of trypan blue to assess lymphatic function following trabeculectomy.

IMPORTANCE: To illustrate the importance of lymphatic drainage in assessing trabeculectomy bleb function using intracameral trypan blue. BACKGROUND: To study the lymphatic drainage of trabeculectomy blebs using trypan blue, correlate with bleb function and classify them accordingly. DESIGN: Prospective cross-sectional study in a tertiary care centre. PARTICIPANTS: Thirteen glaucoma patients post-trabeculectomy were studied. METHODS: Trypan blue was injected into the anterior chamber. MAIN OUTCOME MEASURES: The duration taken for dye to stain a drainage bleb or lymphatics is recorded. The extent of the lymphatic structures were measured in clock hours. Intraocular pressure (IOP) prior to surgery was recorded. RESULTS: Eight post-trabeculectomy subjects with dye stained lymphatic vessels had lower IOP (12.6 mmHg, P = .013) compared to the five with no lymphatic vessel staining (mean IOP 23.6 mmHg). Lymphatic extent was inversely related to IOP (P = .021). CONCLUSIONS AND RELEVANCE: Eyes with lymphatic connections to drainage blebs had lower IOP and reduced requirement for topical medications. The extent of lymphatic connection to drainage blebs is related to lower IOP.

Genomes of ubiquitous marine and hypersaline Hydrogenovibrio, Thiomicrorhabdus and Thiomicrospira spp. encode a diversity of mechanisms to sustain chemolithoautotrophy in heterogeneous environments.

Chemolithoautotrophic bacteria from the genera Hydrogenovibrio, Thiomicrorhabdus and Thiomicrospira are common, sometimes dominant, isolates from sulfidic habitats including hydrothermal vents, soda and salt lakes and marine sediments. Their genome sequences confirm their membership in a deeply branching clade of the Gammaproteobacteria. Several adaptations to heterogeneous habitats are apparent. Their genomes include large numbers of genes for sensing and responding to their environment (EAL- and GGDEF-domain proteins and methyl-accepting chemotaxis proteins) despite their small sizes (2.1-3.1 Mbp). An array of sulfur-oxidizing complexes are encoded, likely to facilitate these organisms' use of multiple forms of reduced sulfur as electron donors. Hydrogenase genes are present in some taxa, including group 1d and 2b hydrogenases in Hydrogenovibrio marinus and H. thermophilus MA2-6, acquired via horizontal gene transfer. In addition to high-affinity cbb3 cytochrome c oxidase, some also encode cytochrome bd-type quinol oxidase or ba3 -type cytochrome c oxidase, which could facilitate growth under different oxygen tensions, or maintain redox balance. Carboxysome operons are present in most, with genes downstream encoding transporters from four evolutionarily distinct families, which may act with the carboxysomes to form CO2 concentrating mechanisms. These adaptations to habitat variability likely contribute to the cosmopolitan distribution of these organisms.

Intermediate-term and long-term outcome of piggyback drainage: connecting glaucoma drainage device to a device in-situ for improved intraocular pressure control.

IMPORTANCE: This study provides results of a treatment option for patients with failed primary glaucoma drainage device. BACKGROUND: The study aimed to describe and evaluate the long-term intraocular pressure control and complications of a new technique joining a second glaucoma drainage device directly to an existing glaucoma drainage device termed 'piggyback drainage'. DESIGN: This is a retrospective, interventional cohort study. PARTICIPANTS: Eighteen eyes of 17 patients who underwent piggyback drainage between 2004 and 2013 inclusive have been studied. All patients had prior glaucoma drainage device with uncontrolled intraocular pressure. METHODS: The piggyback technique involved suturing a Baerveldt (250 or 350 mm) or Molteno3 glaucoma drainage device to an unused scleral quadrant and connecting the silicone tube to the primary plate bleb. MAIN OUTCOME MEASURES: Failure of intraocular pressure control defined as an intraocular pressure greater than 21 mmHg on maximal therapy on two separate occasions or further intervention to control intraocular pressure. RESULTS: The intraocular pressure was controlled in seven eyes (39%) at last follow-up with a mean follow-up time of 74.2 months. The mean preoperative intraocular pressure was 27.1 mmHg (95% confidence interval 23.8-30.3) compared with 18.4 mmHg (95% confidence interval 13.9-22.8) at last follow-up. The mean time to failure was 57.1 months (95% confidence interval 32.2-82), and the mean time to further surgery was 72.3 months (95% confidence interval 49.9-94.7). Lower preoperative intraocular pressure was associated with longer duration of intraocular pressure control (P = 0.048). If the intraocular pressure was controlled over 2 years, it continued to be controlled over the long term. Two eyes (11%) experienced corneal decompensation. CONCLUSIONS: Piggyback drainage represents a viable surgical alternative for the treatment of patients with severe glaucoma with failing primary glaucoma drainage device, particularly in those at high risk of corneal decompensation.

Impact of retinal pigment epithelium pathology on spectral-domain optical coherence tomography-derived macular thickness and volume metrics and their intersession repeatability.

BACKGROUND: To determine the impact of retinal pigment epithelium (RPE) pathology on intersession repeatability of retinal thickness and volume metrics derived from Spectralis spectral-domain optical coherence tomography (Heidelberg Engineering, Heidelberg, Germany). DESIGN: Prospective cross-sectional single centre study. PARTICIPANTS: A total of 56 eyes of 56 subjects were divided into three groups: (i) normal RPE band (25 eyes); (ii) RPE elevation: macular soft drusen (13 eyes); and (iii) RPE attenuation: geographic atrophy or inherited retinal diseases (18 eyes). METHODS: Each subject underwent three consecutive follow-up macular raster scans (61 B-scans at 119 µm separation) at 1-month intervals. MAIN OUTCOME MEASURES: Retinal thicknesses and volumes for each zone of the macular subfields before and after manual correction of segmentation error. Coefficients of repeatability (CR) were calculated. RESULTS: Mean (range) age was 57 (21-88) years. Mean central subfield thickness (CST) and total macular volume were 264 and 258 µm (P = 0.62), and 8.0 and 7.8 mm3 (P = 0.31), before and after manual correction. Intersession CR (95% confidence interval) for CST and total macular volume were reduced from 40 (38-41) to 8.3 (8.1-8.5) and 0.62 to 0.16 mm3 after manual correction of segmentation lines. CR for CST were 7.4, 23.5 and 66.7 µm before and 7.0, 10.9 and 7.6 µm after manual correction in groups i, ii and iii. CONCLUSIONS: Segmentation error in eyes with RPE disease has a significant impact on intersession repeatability of Spectralis spectral-domain optical coherence tomography macular thickness and volume metrics. Careful examination of each B-scan and manual adjustment can enhance the utility of quantitative measurement. Improved automated segmentation algorithms are needed.

Structural characteristics of the optic nerve head influencing human retinal venous pulsations.

The relationship between structural characteristics of the optic nerve head and venous pulsations in the human eye remain unknown. Using photoplethysmographic techniques we investigated whether properties of the human retinal veins and their surrounding structures influence venous pulsation. 448 locations of venous pulsation were analysed from 26 normal human eyes. Green channel densitometry derived from video recordings of venous pulsations were used to generate a map of venous pulsation amplitudes along retinal veins. Optical coherence tomography was used to perform quantitative measurements of tissue characteristics at sites of high and low amplitude points as well as in a second analysis, at maximal amplitude pulsation sites from superior and inferior halves of the eyes. Structural characteristics measured included venous diameter, distance from pulsation point to cup margin, vessel length from pulsation point to vein exit, tissue thickness overlying vein, optic disc diameter and presence of a proximal arteriovenous crossing. Increasing venous pulsation amplitudes were associated with larger applied ophthalmodynamometry force, increasing venous diameter, and decreasing absolute cup margin distance (all p < 0.001). Increasing distance of maximal amplitude pulsation point to cup margin was associated with the presence of a proximal arteriovenous crossing, increasing venous diameter, and decreasing tissue depth (all p ≤ 0.001). Venous diameter and tissue depth alter venous compliance, which is likely to be a major factor determining sites of venous pulsation.

Inter-device comparison of retinal sensitivity measurements: the CenterVue MAIA and the Nidek MP-1.

BACKGROUND: Our aim is to compare retinal sensitivity measurements obtained on two microperimeters: the CenterVue MAIA and the Nidek MP-1. DESIGN: A prospective study was conducted in a private ophthalmology clinic. PARTICIPANTS: Seventeen individuals with a range of stable macular function were recruited as participants. METHODS: Microperimetry in one eye with identical test strategy in both devices, with randomized testing order, is used. MAIN OUTCOME MEASURES: The main outcome measures include differences in mean sensitivity (MS), point-wise sensitivity (PWS) and duration. Limits of agreement (LoA) in MS and pooled PWS were calculated. Concordance in scotoma assessment was analysed by kappa (κ) agreement of local defect classification (LDC), LoA in number of scotomatous loci detected and congruence in scotoma localization (CSL). RESULTS: Median (interquartile range) MS of the MP-1 and MAIA was 13.3 (5.6-18.1) and 21.2 (14.5-27.0) dB, (P < 0.05). Mean difference in PWS was 7.3 dB (MAIA > MP-1). Median (interquartile range) duration for the MP-1 and MAIA was 10'28″ (7'17″-11'53″) and 8'46″ (8'30″-9'06″), (P = 0.21). LoA for MS and pooled PWS was 1.4 to 13.3 dB and -3.9 to 18.5 dB. There was moderate agreement between the devices for LDC (weighted κ = 0.55, P < 0.05). LoA in number of scotomatous loci detected was -13 to 18. CSL varied from 0 to 100% and correlated strongly with increasing scotoma size. CONCLUSIONS: The large LoA and variation in scotoma mapping concordance suggest that the same microperimeter should be used for follow-up examination. We recommend caution in comparing results derived from different types of microperimeters.