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At least 19 recordsLinked to original sources

Imaging-Guided Omics Technologies for Resolving Rare Cancer States and Advancing Nanomedicine.

The ability to resolve rare and transient cellular states is critical for understanding metastasis, immune evasion, and therapy resistance in cancer, yet these dynamic processes often escape detection by conventional sequencing and imaging approaches. Recent advances at the interface of nanotechnology, high-resolution live-cell imaging, and single-cell/spatial multiomics methods have enabled functional profiling of cells with unprecedented precision within their native microenvironment. In this Mini-Review, we highlight emerging nanoscale platforms that couple real-time phenotypic imaging with molecular readouts, such as FUNseq and CIN-seq, to directly link functional heterogeneity to transcriptomic, proteomic, and epigenomic information. By integrating nanoscale optical imaging, microengineered perturbation tools, and AI-driven computational analysis, these technologies open up new avenues for dissecting rare metastatic, therapy-resistant, or immune-evasive subpopulations. We further discuss how these next-generation imaging-guided single-cell and spatial omics platforms not only advance fundamental cancer biology but also create opportunities to accelerate the development of nanomedicine applications.

Humans

MedImg: An Integrated Database for Public Medical Images.

The advancements in deep learning algorithms for medical image analysis have garnered significant attention in recent years. While several studies have shown promising results, with models achieving or even surpassing human performance, translating these advancements into clinical practice is still accompanied by various challenges. A primary obstacle lies in the availability of large-scale, well-characterized datasets for validating the generalization of approaches. To address this challenge, we curated a diverse collection of medical image datasets from multiple public sources, containing 105 datasets and a total of 1,995,671 images. These images span 14 modalities, including X-ray, computed tomography, magnetic resonance imaging, optical coherence tomography, ultrasound, and endoscopy, and originate from 13 organs, such as the lung, brain, eye, and heart. Subsequently, we constructed an online database, MedImg, which incorporates and systematically organizes these medical images to facilitate data accessibility. MedImg serves as an intuitive and open-access platform for facilitating research in deep learning-based medical image analysis, accessible at https://www.cuilab.cn/medimg/.

Humans

A systematic review of macaque brain stimulation: Trends and future directions.

Neurostimulation techniques can powerfully modulate neural circuit activity and provide causal insights into the relationship between brain function and behavior. Macaque monkeys have long been a key animal model for brain stimulation studies. While stimulating the macaque brain with one or a few electrodes has already taught us much about brain function and dysfunction, recent technological advances promise a future with more precise stimulation using many more electrodes. However, such possibilities also increase the number of choices an experimenter has when designing their study. We can learn from a rich past, but a comprehensive overview of which brain regions have been studied and with what stimulation parameters is lacking. Here, we present a PRISMA-compliant systematic review of 734 macaque brain stimulation studies using electrical and/or optogenetic stimulation. We find a striking bias in which brain areas have traditionally been stimulated: a mere 10 brain regions account for half of all studies, with the remainder of studies investigating approximately 150 other areas. Across studies, stimulation frequency robustly predicted direct behavioral effects independent of brain region, while amplitude did not. Future studies could more systematically explore less studied regions through lower stimulation frequencies (e.g., 20-50 Hz) alongside established ranges (∼200 Hz). Tools such as fMRI or optical imaging can capture neural circuit engagement evoked by these frequencies, even when behavioral effects are absent or remain subtle. Our synthesis offers a guide towards the next steps in high-channel-count, high-precision stimulation approaches.

Animals

A G-Quadruplex-Activated Near-Infrared Chemiluminescent Probe for In Situ Hepatic Imaging of the Hepatitis C Virus Genome.

Real-time monitoring of viral replication is essential for infectious disease diagnosis and antiviral drug development. The G-quadruplex (G4), a conserved regulatory element within viral genomes, represents a significant endogenous biomarker for tracking viral activity. However, imaging viral G4s in deep tissues remains a challenge for current optical technologies due to severe photon attenuation and autofluorescence. Herein, we report Lumin680, the first near-infrared (NIR) chemiluminescent probe directly activated by conserved viral G4 conformations. Its chemiluminescence was triggered by parallel G4, emitting in the NIR optical window (680 nm) with a 104.6-fold signal enhancement. Notably, the luminescence of Lumin680 could penetrate up to 1.2 cm of biological tissue, outperforming traditional G4 fluorescent probe. In vivo, Lumin680 enabled the rapid visualization of orthotopic hepatitis C virus (HCV) genome RNA-presenting mini-organ within 5 min post-intravenous administration. Furthermore, the chemiluminescent intensity of Lumin680 quantitatively mapped the therapeutic efficacy of clinical direct-acting antivirals (DAAs) at both the cellular and whole-animal levels, exhibiting high concordance with the gold-standard quantitative RT-PCR (qPCR). This study not only provides a powerful G4 specific chemiluminescent tool but also establishes a novel paradigm for the non-invasive, in situ diagnosis and precise therapeutic monitoring of viral infections.

G-Quadruplexes

High-Plex Tissue Imaging with Conventional Immunofluorescence Platforms and Open-Source Software via Iterative Bleaching Extends Multiplexity (IBEX).

Iterative bleaching extends multiplexity (IBEX) is an easy-to-use, highly multiplex immunofluorescent tissue imaging method that employs widely available microscopy platforms, commercial reagents, and open-source software. In this article, we describe how to implement this method in a laboratory that has minimal experience with immunohistochemistry.

Software

From Static to Dynamic: Fluorescence Imaging Technology Advances Precise Embryo Evaluation.

Live-cell imaging technology has revolutionized our understanding of preimplantation embryonic development, shifting the field from static morphological descriptions to dynamic functional analyses. This has tremendously advanced the fields of in vitro fertilization (IVF) and embryonic development. At the heart of this transition lies the strategic application of fluorescent probes, which provide the requisite sensitivity and specificity to resolve complex biological events. This review provides a comprehensive overview of fluorescent probe-based strategies designed to address four cardinal questions in peri-implantation embryology: genomic stability, cell fate determination, tissue morphogenesis, and embryo-maternal interactions. We systematically evaluate the chemical design principles and imaging modalities of various probes, which range from small-molecule organic fluorophores to genetically encoded reporters and nanoparticle-based sensors. Furthermore, we discuss how these tools facilitate the real-time visualization of chromosomal aberrations, lineage segregation, biomechanical forces, and enzymatic activities within the delicate embryonic microenvironment. This review summarizes methodological strategies for selecting and developing optimal probes across diverse application contexts. By identifying current technical bottlenecks and proposing future directions, such as NIR-II imaging and noninvasive labeling, it aims to drive the translation of basic embryonic research into advanced reproductive medicine.

Humans

Impact of Diabetes on Outcomes of Contemporary PCI Guided by OCT vs Angiography: The ILUMIEN IV Trial.

BACKGROUND: Patients with diabetes are at higher risk for adverse events after percutaneous coronary intervention (PCI) compared with patients without diabetes. OBJECTIVES: This study sought to assess the influence of diabetes and complex lesions on the outcomes of patients undergoing PCI with and without optical coherence tomography (OCT) guidance during a follow-up period of 2 years. METHODS: Patients in ILUMIEN IV randomized to OCT-guided vs angiography-guided PCI were grouped into those with (n = 1,044) and without diabetes (n = 1,443). Study endpoints were target vessel failure (TVF) and serious major adverse cardiovascular events (MACE). RESULTS: After adjustment for differences in clinical and angiographic characteristics, the 2-year rates of both TVF (9.9% vs 6.3%; adjusted HR: 1.48; 95% CI: 1.09-2.02; P = 0.01) and serious MACE (5.3% vs 2.7%; adjusted HR: 1.77; 95% CI: 1.14-2.76; P = 0.01) were increased in diabetic compared with nondiabetic patients, consistently in patients with and without complex lesions (Pinteraction = 0.22 and 0.14, respectively), although the highest 2-year rates were in patients with diabetes and complex lesions. In all randomized patients, OCT guidance compared with angiography guidance did not reduce TVF or serious MACE. These effects were consistent in patients with and without diabetes (Pinteraction = 0.41 and 0.20, respectively), and were not modified by treatment of complex lesions. CONCLUSIONS: In the large-scale ILUMIEN IV trial, patients with diabetes remained at increased risk for adverse events after PCI compared with nondiabetic patients despite the use of OCT procedural guidance. Patients with diabetes and complex lesions were at particularly high risk for adverse outcomes after PCI.

Humans

Intraoperative indocyanine green near-infrared fluorescence imaging for assessing testicular viability in pediatric testicular torsion: A retrospective study.

OBJECTIVE: To evaluate the clinical efficacy of indocyanine green near-infrared fluorescence (ICG-NIRF) imaging versus conventional surgery for assessing testicular viability and guiding decision-making in pediatric testicular torsion (TT). METHODS: A retrospective analysis was performed on 225 pediatric patients undergoing emergency scrotal exploration for TT between January 2019 and January 2025. Patients were categorized into a conventional surgery group (n = 118) relying on visual grading and an ICG-NIRF imaging group (n = 107). Primary outcomes included intraoperative testicular preservation rates and postoperative success rates. Multivariate Cox regression was utilized to identify factors influencing testicular preservation. RESULTS: Baseline characteristics were comparable between groups. The ICG-NIRF group demonstrated a significantly higher intraoperative preservation rate (74.77% vs. 61.02%, p = 0.028) and postoperative success rate (88.75% vs. 69.44%, p = 0.003) compared to the conventional group. Additionally, the ICG-NIRF group exhibited significantly lower rates of secondary orchiectomy (1.25% vs. 9.72%, p = 0.027) and 6-month testicular atrophy (7.59% vs. 23.08%, p = 0.02). Multivariate analysis confirmed ICG-NIRF application as an independent protective factor for testicular preservation (HR = 0.556, p < 0.001). CONCLUSION: ICG-NIRF imaging provides an objective, real-time assessment of testicular perfusion, significantly improving testicular preservation rates and postoperative outcomes. This technique overcomes the subjectivity of conventional visual methods, offering substantial clinical value for fertility preservation in pediatric TT.

Humans

Application of Perioperative Real-Time Fluorescence Imaging to Achieve High-Quality Debridement: A Randomized Control Trial.

OBJECTIVE: To investigate the effectiveness of real-time fluorescence imaging (RTFI)-assisted debridement in managing chronic wounds compared with standard surgical debridement. APPROACH: This study was a patient-blinded, randomized clinical trial conducted from February 17, 2021, to July 30, 2021, on patients with chronic wounds. Patients were randomized to an RTFI group (M group) or conventional group (C group). The primary outcomes were as follows: percentage of residual bacterial area (preoperative and postoperative), number of debridements, high-quality debridement ratio, operation duration, and wound healing duration. RESULTS: A total of 100 patients were enrolled in both groups. No significant difference in the percentage of preoperative residual bacterial area or high-quality debridement ratio was seen. The M group underwent debridement an average of 2.6 times and had a significantly longer duration of operation (33.5 &#xb1; 12.7 min) than the C group (29.9 &#xb1; 10.4 min; p = 0.031). The postoperative residual bacterial area was significantly lower in the M than in the C group (6.83% &#xb1; 1.39% vs. 30.0% &#xb1; 12.37%, respectively; p < 0.001). The M group required significantly fewer wound healing days (49.2 &#xb1; 25.3 vs. 63.0 &#xb1; 27.9, p < 0.001). Secondary outcomes also demonstrated statistically significant differences in total hospitalized days (17.5 &#xb1; 9.3 vs. 21.5 &#xb1; 12.5, p < 0.01), days of antibiotic use (15.5 &#xb1; 8.7 vs. 18.7 &#xb1; 6.7, p < 0.01), and reinfection rates (4 of 100 vs. 22 of 100, p < 0.001). INNOVATION: RTFI can detect signals from normal skin components and bacterial metabolites. Therefore, interpretation of RTFI results should be correlated with the clinical condition. RTFI is associated with high-quality debridement. This technique can also be applied in targeted biopsy and in training young staff to mature debridement procedures. CONCLUSION: RTFI in debridement is associated with favorable clinical outcomes and may have a positive influence on chronic wound healing.

Humans

Retinal microstructural alterations as early phenotypes of depression in radiogenomics analysis.

BACKGROUND: With the increasing prevalence of depression, there is an urgent clinical need for early screening in depression. The retina offers a promising window for early screening in depression due to its rapid, non-invasive, objective, eye-brain correlated characteristics, but previous research has yielded conflicting alterations in retinal microstructure in depression. METHODS: We screened retinal optical coherence tomography and brain magnetic resonance imaging data in the UK Biobank to enroll 23,225 participants for retinal study of depression occurrence, and 1475 participants for the eye-brain association study. We also used genetic data (ID: ebi-a-GCST90014267 and ukb-d-20,448) from the Integrative Epidemiology Unit Open Genome-Wide Association Study for Mendelian randomization analysis. We used Cox regression to assess the association between retinal microstructure and depression risk, Mendelian randomization to infer causality, and mediation analysis to explore retina-brain pathway association. RESULTS: The Cox regression analysis showed that retinal ganglion cell-inner plexiform layer (GCIPL) thickness remained a significant predictor of depression. The Mendelian randomization analysis indicated a positive statistical association between GCIPL thickness and depression. Moreover, there was a significant positive correlation (all p&#xa0;<&#xa0;0.001) between the volume of specific depression-related brain regions and the GCIPL thickness. Adjusting for age, sex, and head size, the mediation analysis provided preliminary evidence for a potential anatomical pathway linking retinal GCIPL thickness to depression-related brain regions through primary visual cortex and secondary visual cortex volumes. CONCLUSION: Thickened retinal GCIPL is a potential early phenotype of depression and has a potential association pathway with depression-related brain regions using a radiogenomics approach.

Humans

Development and validation of a deep learning model based on cascade mask regional convolutional neural network to noninvasively and accurately identify human round spermatids.

INTRODUCTION: The difficulty of identifying human round spermatids (hRSs) has impeded applications of the human round spermatid injection (ROSI) technique. RSs can be accurately screened through flow cytometric analysis utilizing the Hoechst fluorescence profile reflecting DNA, but this method is not suitable for isolating hRSs due to the toxicity associated with Hoechst staining. OBJECTIVE: To evaluate the capacity of a deep learning model grounded in a cascade mask region-based convolutional neural network (R-CNN) for the noninvasive and accurate identification of hRSs. METHODS: In this study, we presented the development and validation of a deep learning model for identifying hRSs through the analysis of 3457 optical light microscope images of sorted hRSs obtained via flow cytometric analysis. The model's accuracy and specificity were evaluated by calculating the mean average precision (mAP). Furthermore, a double-blind experiment was conducted to access the reliability of the proposed model in accurately identifying hRSs. It detected the expression of protamine (PRM1) and/or peanut lectin (PNA), which are established markers for RSs. RESULTS: Our deep learning-based model demonstrated a high precision, achieving a mAP of over 0.80 for isolating hRSs in test datasets. The expression of PRM1 and/or PNA was observed in all cells noninvasively selected by our AI model during an independent double-blind test. This phenomenon confirmed the accuracy and effectiveness of the proposed model. The model's capability for noninvasive and accurate isolation of hRSs among spermatogenic cells highlighted its robustness and generalizability for clinical applications. CONCLUSION: The deep learning AI model based on a cascade R-CNN has the ability to accurately identify hRSs among spermatogenic cells. The application of this noninvasive method, which requires no additional procedures in clinical practice, is able to facilitate the widespread implementation of ROSI technique. Therefore, it can provide patients with spermatogenic arrest the opportunity to become biological fathers.

Humans

Ophthalmic imaging as a measure of cardiovascular and neurological health: a multi-omic analysis of deep-learning derived phenotypes.

The eye is a recognised source of biomarkers for cardiovascular and neurodegenerative disease risk. Here, we characterise the breadth of these associations and identify biological axes that may mediate them. Using UK Biobank data, we developed a multi-omic analysis pipeline integrating physiological, radiomic, metabolomic, and genomic information. We trained adversarial autoencoders (Ret-AAE) to represent optical coherence tomography (OCT) images and colour fundus photographs as 256-dimensional embeddings. Ret-AAE derived embeddings were associated with a range of cardiovascular and neurodegenerative diseases, including ischaemic heart disease, cerebrovascular disease, Parkinson's disease, and dementia. Examining associations across diverse omics datasets, we provide evidence linking ophthalmic imaging features to neurological and cardiovascular anatomy and function, lipid metabolism, and gene sets associated with neurodegenerative pathology. Collectively, our findings demonstrate that ophthalmic features reflect complex, multisystem biological processes, and reinforce the role of the eye as a composite indicator of systemic health.

Journal Article

GWAS Meta-analysis Identifies Novel Associated Loci and Points to Causal Tissues in Central Serous Chorioretinopathy.

OBJECTIVE: To define CSC genetic architecture and identify implicated ocular tissues, cell types, genes, and circulating proteins. DATA SOURCES: Genome-wide data were assembled from FinnGen, All of Us, Mass General Brigham Biobank, Million Veteran Program, and a Dutch chronic CSC cohort. Serum protein quantitative trait loci, human single-cell ocular atlases, and UK Biobank macular optical coherence tomography (OCT) imaging were used for downstream analyses. STUDY SELECTION: Five European-ancestry cohorts with genome-wide data and cohort-specific CSC case-control definitions were included, comprising 2,584 cases and 1,044,455 controls. Variants present in at least 2 cohorts were meta-analyzed. DATA EXTRACTION AND SYNTHESIS: Cohort-level GWASs were adjusted for age, age squared, sex, genotyping array or batch, and 10 genetic principal components, then combined using fixed-effects inverse-variance meta-analysis. Post-GWAS analyses included gene prioritization, colocalization, Mendelian randomization, single-cell disease-relevance scoring, and testing of a CSC genetic risk score in UK Biobank OCT images. MAIN OUTCOMES AND MEASURES: Genome-wide significant CSC loci, effector genes and proteins, tissue and cell-type enrichment, and CSC-relevant OCT abnormalities. RESULTS: Across 11,068,938 variants, 10 loci reached genome-wide significance (P < 5 &#xd7; 10-8), including 3 novel loci near TGFB1, LINC00551, and LOC105375630 and 7 replicated loci near CFH, CD46, NOTCH4, PREX1, PTPRB, GATA5, and TNFRSF10A. Integrative analyses prioritized 10 candidate effector genes. Colocalization and Mendelian randomization implicated circulating TNFRSF10A, TGFB1, and CASP10 levels. Single-cell analyses localized genetic risk to sclera (P = 2.0 &#xd7; 10-4) and vascular endothelial cells (P = 4.0 &#xd7; 10-4), with fibroblast enrichment. In UK Biobank, OCT abnormalities were more frequent in the top vs bottom 1% of CSC genetic risk (18 of 109 [16.5%] vs 8 of 134 [6.0%]; odds ratio, 4.05; 95% CI, 1.65-10.87; P = .002). CONCLUSIONS AND RELEVANCE: In this GWAS meta-analysis, CSC susceptibility localized predominantly to scleral and vascular biology rather than primary retinal pigment epithelial dysfunction. These findings support CSC as a sclerovascular disorder and nominate complement regulation, endothelial signaling, and extracellular matrix pathways for future study.

Journal Article

Biallelic loss-of-function variants in C19orf44 lead to retinal degeneration.

BACKGROUND: Inherited retinal diseases (IRDs) are a group of disorders often resulting in progressive vision loss, ultimately leading to blindness. A significant portion of their genetic causes remain unresolved, partly due to undiscovered disease-associated genes or variants. This study aimed to identify novel genetic links to IRDs. METHODS: All patients underwent comprehensive ophthalmological evaluation, including retinal imaging (fundus autofluorescence and macular optical coherence tomography) and electroretinogram testing. Whole exome sequencing and whole genome sequencing were performed on patients with clinically unsolved IRD, and data were analysed using an in-house pipeline to identify causal variants. Subsequently, Sanger sequencing was performed to confirm identified variants. RESULTS: Three unrelated patients from Europe, Middle East and East Asia were identified with unique late-onset retinal degeneration (Stargardt-like phenotype) associated with biallelic loss-of-function (LoF) variants in C19orf44 (HGNC: 26141), a gene of unknown function. The homozygous variant NM_032207.2:c.549_550del;p.Ser185Profs*2 was identified in two unrelated patients (European and Middle Eastern). Moreover, an East Asian patient had likely compound heterozygous LoF variants (NM_032207.2:c.1168C>T;p.Gln390*/c.976_977del;p.Leu326Lysfs*15). CONCLUSIONS: Our findings establish C19orf44 as a novel disease-causing gene for IRD with Stargardt-like phenotype, expanding the genetic landscape of retinal degeneration.

Humans

Genetic influence on choroidal vascularity index.

PURPOSE: To investigate the heritability of genetic influence on macular choroidal vascularity index (CVI). METHODS: Total choroidal area (TCA), luminal area (LA), and CVI was measured using horizontal scan of spectral-domain optical coherence tomography with enhanced depth imaging in the 373 healthy twin participants. Characteristics of the participants were investigated, including age, sex, axial length, hypertension, diabetes, drinking habits, and smoking status. Univariate and subsequent multivariate regression analyses were performed to evaluate the associations of these factors with TCA, LA, and CVI. RESULTS: Patients who were older and had a higher intraocular pressure, higher diastolic blood pressure, and lower pulse pressure showed associations with lower CVI (p<0.001, p = 0.014, p = 0.005, and p = 0.015, respectively). The covariate-adjusted heritability (&#xb1;standard error) of the CVI was 0.716 &#xb1; 0.091, and the heritabilities of the TCA and LA were 0.691 &#xb1; 0.089 and 0.634 &#xb1; 0.100, respectively. CONCLUSION: The TCA, LA, and CVI are highly heritable.

Humans

Ciliochoroidal Effusion and Regional Scleral Thickening in Peripapillary Pachychoroid Syndrome.

PURPOSE: To assess anterior scleral thickness and the presence of ciliochoroidal effusion (CE) in eyes with peripapillary pachychoroid syndrome (PPS), and to compare the results with a cohort of healthy age-matched controls. DESIGN: Retrospective cross-sectional study METHODS: A total of 20 eyes from 12 patients diagnosed with PPS and 30 eyes from 15 healthy control subjects. All participants underwent a comprehensive ophthalmic examination, including spectral-domain optical coherence tomography with enhanced depth imaging (EDI-OCT) and anterior segment OCT (AS-OCT). Choroidal thickness was measured at predefined macular and peripapillary locations, while anterior scleral thickness was assessed 6 mm posterior to the scleral spur in 4 quadrants. Ciliochoroidal effusion was evaluated qualitatively using AS-OCT. Comparisons between groups were performed using linear mixed models with Bonferroni correction (scleral thickness corrected P < .010) RESULTS: The mean age of PPS patients was 75.6 &#xb1; 9.8 years, and 16% were females. Anterior scleral thickness was significantly greater in the temporal quadrant in PPS eyes compared to controls (396.85 &#xb1; 74.97 &#xb5;m vs 331.13 &#xb1; 62.65 &#xb5;m: P = .007). Ciliochoroidal effusion was detected in 60% of PPS eyes, predominantly in the superior and temporal sectors, whereas no effusion was observed in healthy controls (P < .001). Eyes with CE exhibited a thicker mean scleral thickness and a thicker subfoveal choroidal thickness compared to eyes without effusion (P < .05). CONCLUSION: Eyes with PPS demonstrated increased temporal scleral thickness and a high prevalence of CE. These findings suggest that scleral characteristics may represent a predisposing anatomical factor in PPS, although the precise pathophysiological mechanisms remain to be elucidated.

Humans

Optics-free spatial genomics for mapping mammalian brain aging by IRISeq.

Spatial transcriptomics has emerged as a transformative approach for in situ mapping of cellular heterogeneity and interactions, yet existing methods often compromise throughput, cost and tissue coverage. Here we introduce Imaging Reconstruction using Indexed Sequencing (IRISeq): an optics-free, cost-effective platform that leverages spatial interaction mapping by indexed sequencing to profile tissues at adjustable sizes and resolutions (5-50&#x2009;&#xb5;m). We applied IRISeq to map gene expression across more than 70 coronal sections from both adult and aged mouse brains, including wild-type and two lymphocyte-deficient models (Rag1 and Prkdc mutants) and generated more than 460,000 spatial transcriptome profiles. Our integrated analysis with 783,264 single-cell transcriptomes revealed region-specific aging signatures that are lymphocyte dependent, notably a downregulation of interferon signaling and inflammation in ventricular regions upon lymphocyte depletion, alongside mutant-specific upregulation of senescence pathways. Furthermore, lymphocyte deficiency was linked to preserved abundance of ependymal cells that line the brain's ventricles and to distinct microglial state dynamics, highlighting a key role for lymphocytes in driving inflammatory processes during brain aging. Overall, IRISeq provides a high-throughput and cost-effective solution for spatially resolved transcriptomic profiling, opening new avenues for elucidating region-specific cellular mechanisms underlying aging and identifying potential therapeutic targets to preserve brain homeostasis.

Animals

Can we identify people with Alzheimer's disease from examination of the eye? A bidirectional Mendelian randomization (MR) study.

BACKGROUND: Neurodegeneration in Alzheimer's disease (AD) is thought to be driven by amyloid-beta and tau deposition in the cerebral vasculature and brain. As the eye is an extension of the central nervous system, this study aimed to determine which neurovascular and neuroretinal changes in the eye are caused by AD rather than associations of the disease. METHODS: Bidirectional two-sample univariable and multivariable Mendelian randomization (MR) methods were applied. Instrumental variables were derived from genome-wide association studies (GWAS) of AD and the following ocular features: thickness measurements of central macula (MT), retinal nerve fibre layer (mRNFL), ganglion cell-inner plexiform layer (mGCIPL), outer nuclear layer (ONL), inner segment layer (IS), and outer segment (OS) from macular region OCT scans; arteriolar tortuosity (AT), venular tortuosity (VT), venular width (VW), fractal dimension (FD), vertical cup-to-disc ratio (VCDR), optic cup area (OCA), and optic disc area (ODA) derived from other imaging methods. RESULTS: There was strong evidence that genetic liability to AD affected the retinal vasculature by specifically increasing AT (&#x3b2; = 0.007;95%CI=0.002,0.011;p-value=0.005) in UK Biobank participants (n=52,798). AD may influence the mRNFL (&#x3b2;=-0.047,95%CI=-0.119,0.023,p-value=0.18) and mGCIPL (&#x3b2;=-0.061;95%CI=-0.14,0.025,p-value=0.16) of the inner retina and OS layer (&#x3b2; = 0.044;95%CI=-0.0001,0.08;p-value=0.05) but the evidence was weak. Multivariable MR analysis showed that a causal relationship between optic disc area and AD (OR=0.76;95%CI=0.62,0.93,p-value=0.009) was probably mediated by refractive error. CONCLUSION: Early cerebrovascular signs of AD may be detected by examination of the eye. Further investigation is required to determine the clinical utility of eye screening for dementia.

Humans