Agarwal A, Agrawal R, Raje D, Testi I, Mahajan S, Gunasekeran DV, Aggarwal K, Murthy SI, Westcott M, Chee S-P, McCluskey P, Ho SL, Teoh S, Cimino L, Biswas J, Narain S, Agarwal M, Mahendradas P, Khairallah M, Jones N, Tugal-Tutkun I, Babu K, Basu S, Carreño E, Lee R, Al-Dhibi H, Bodaghi B, Invernizzi A, Goldstein DA, Herbort CP, Barisani-Asenbauer T, González-López JJ, Androudi S, Bansal R, Moharana B, Esposti SD, Tasiopoulou A, Nadarajah S, Agarwal M, Abraham S, Vala R, Singh R, Sharma A, Sharma K, Zierhut M, Kon OM, Cunningham ET, Kempen JH, Nguyen QD, Pavesio C, Gupta V. Twenty-four Month Outcomes in the Collaborative Ocular Tuberculosis Study (COTS)-1: Defining the "Cure" in Ocular Tuberculosis. Ocul Immunol Inflamm 2020;:1-9.Abstract
PURPOSE: To report the clinical findings, anatomical features, and treatment outcomes in subjects with ocular tuberculosis (OTB) at 24 months in the Collaborative Ocular Tuberculosis Study (COTS)-1. METHODS: Of the 945 subjects included in COTS-1, those who completed a 24-month follow-up after completion of treatment were included. The main outcome measure was a number of patients with treatment failure (TF). RESULTS: 228 subjects (120 males; mean age of 42.82 ± 14.73 years) were included. Most common phenotype of uveitis was posterior ( = 81; 35.53%), and panuveitis ( = 76; 33.33%). Fifty-two patients (22.81%) had TF. On univariable analysis, odds of high TF was observed with bilaterality (OR: 3.46, = .003), vitreous haze (OR: 2.14, = .018), and use of immunosuppressive therapies (OR: 5.45, = .003). However, only bilaterality was significant in the multiple regression model (OR: 2.84; = .02). CONCLUSIONS: Majority of subjects (>75%) achieved cure in the COTS-1 at 24-month follow-up. The concept of "cure" may be a valuable clinical endpoint in trials for OTB.
PURPOSE: To evaluate corneal immune dendritiform cell (DC) changes in dry eye disease (DED) using in vivo confocal microscopy (IVCM) and to correlate IVCM parameters with clinical severity. METHODS: This was a retrospective, cross-sectional study including 300 eyes of 150 DED patients and 49 eyes of 49 age-matched controls. Severity of DED was based on the Dry Eye Workshop (DEWS) classification. IVCM images of subbasal layer of the central cornea were analyzed for DC density and morphology (including number of dendrites per DC, DC size and DC field). RESULTS: DC density was significantly higher in DED compared to controls (93.4 ± 6.3 vs. 25.9 ± 3.9 cells/mm; P < 0.001). Morphologically, number of dendrites, DC size and field were significantly larger in DED (3.3 ± 0.1, 106.9 ± 4.7 μm, 403.8 ± 20.1 μm than controls (2.3 ± 0.1, 62.5 ± 5.7 μm, 241.4 ± 24.4 μm, P < 0.001). Significantly higher DC density compared to controls was observed as early as Level 1 DED severity (87 ± 10 cells/mm, p < 0.001. Significant morphological changes in DC were detected for Levels 2 to 4 (p=<0.001, and p =< 0.05) for dendrites and DC field, respectively. Similarly, DC size showed significant increase at DED level 3-4. (p < 0.05). Linear regression analysis showed that both conjunctival and corneal staining were independently associated with DC density, while corneal staining was independently associated with DC morphology. CONCLUSION: DC density and morphology correlated with clinical severity of DED. While, DC density is increased in mild DED, morphological changes are seen only in severe cases. IVCM may be a powerful tool to detect early immune changes and may complement clinical examination in DED.
Background: Visualization during scleral buckling is traditionally achieved via indirect ophthalmoscopy. Recent advances have utilized the surgical microscope and a 25 gauge cannula-based endoillumination system, also known as a Chandelier lighting system. This report details an improved approach using a guarded 25 or 27 gauge light pipe and the Ngenuity digital three dimensional platform. Methods: A standard Alcon light pipe is modified with a silicone guard to expose only 5 mm of the tip of the light pipe. The guard is created from the silicone that is already opened to secure the ends of the encircling band most often employed sleeve (e.g. 70, 270). This guarded light pipe is then inserted into the cannula as an alternative to a Chandelier lighting system. Results: This is a technical report of a surgical visualization technique using a three dimensional digital visualization platform with a modified handheld vitrectomy light pipe. Conclusion: The utilization of a guarded light pipe for visualization during primary scleral buckling is a promising, effective, and efficient technique. The three dimensional digital display allows for better educational impact and surgical communication with trainees and ancillary members of the surgical team.
Agrawal R, Betzler BK, Testi I, Mahajan S, Agarwal A, Gunasekeran DV, Raje D, Aggarwal K, Murthy SI, Westcott M, Chee S-P, McCluskey P, Ho SL, Teoh S, Cimino L, Biswas J, Narain S, Agarwal M, Mahendradas P, Khairallah M, Jones N, Tugal-Tutkun I, Babu K, Basu S, Carreño E, Lee R, Al-Dhibi H, Bodaghi B, Invernizzi A, Goldstein DA, Barisani-Asenbauer T, González-López JJ, Androudi S, Bansal R, Moharana B, Esposti SD, Tasiopoulou A, Nadarajah S, Agarwal M, Abraham S, Vala R, Singh R, Sharma A, Sharma K, Zierhut M, Kon OM, Cunningham ET, Kempen JH, Nguyen QD, Pavesio C, Gupta V. The Collaborative Ocular Tuberculosis Study (COTS)-1: A Multinational Review of 447 Patients with Tubercular Intermediate Uveitis and Panuveitis. Ocul Immunol Inflamm 2020;:1-11.Abstract
Tubercular intermediate uveitis (TIU) and panuveitis (TBP) are difficult to manage because of limitations in diagnostic tools and lack of evidence-based treatment guidelines. The Collaborative Ocular Tuberculosis Study (COTS) analyzed treatment regimens and therapeutic outcomes in patients with TIU and TBP. Multicentre retrospective analysis. A total of 138 TIU and 309 TBP patients were included. A total of 382 subjects received antitubercular therapy (ATT) (n = 382/447; 85.4%) and 382 received corticosteroids (n = 382/447; 85.4%). Treatment failure was observed in 78 individuals (n = 78/447; 17.4%), occurring less frequently in patients receiving ATT (n = 66/382; 17.2%) compared to those who did not (n = 12/65; 18.5%). The study did not show any statistically significant therapeutic effect of ATT in patients with TIU and TBP. Taking into account the limitations of the retrospective, non-randomized study design, resultant reliance on reported data records, and unequal size of the samples, the current study cannot provide conclusive evidence on the therapeutic benefit of ATT in TIU and TBP.
Agrawal R, Testi I, Mahajan S, Yuen YS, Agarwal A, Rousselot A, Raje D, Gunasekeran DV, Kon OM, Barisani-Asenbauer T, Kempen JH, Gupta A, Jabs DA, Smith JR, Bodaghi B, Zierhut M, DeSmet M, McCluskey P, Agarwal M, Agarwal M, Aggarwal K, Agrawal M, Al-Dhibi H, Androudi S, Asyari F, Balasundaram MB, Murthy KB, Baglivo E, Banker A, Bansal R, Basu S, Behera D, Biswas J, Carreño E, Caspers L, Chee SP, Chhabra R, Cimino L, Del Rio LEC, Cunningham ET, Curi ALL, Das D, Denisova E, Denniston AK, Errera M-H, Fonollosa A, George A, Goldstein DA, Crosier YG, Gurbaxani A, Invernizzi A, Isa HM, Md Islam S, Jones N, Katoch D, Khairallah M, Khosla A, Kramer M, Kumar A, Kumar A, Distia Nora RL, Lee R, Lowder C, Luthra S, Mahendradas P, Makhoul D, Mazumdar S, Mehta S, Miserocchi E, Mochizuki M, Mohamed OS, Muccioli C, Munk MR, Murthy S, Narain S, Nascimento H, Neri P, Nguyen M, Okada AA, Ozdal P, Palestine A, Pichi F, Rathinam SR, Schlaen A, Sehgal S, Sen NH, Sharma A, Sharma K, Shoughy SS, Singh N, Singh R, Soheilian M, Sridharan S, Thorne JE, Tappeiner C, Teoh S, Tognon MS, Tugal-Tutkun I, Tyagi M, Uy H, Santos DVV, Valentincic NV, Westcott M, Yanai R, Alvarez BY, Zahedur R, Nguyen QD, Pavesio C, Gupta V. The Collaborative Ocular Tuberculosis Study (COTS) Consensus (CON) Group Meeting Proceedings. Ocul Immunol Inflamm 2020;:1-11.Abstract
An international, expert led consensus initiative was set up by the Collaborative Ocular Tuberculosis Study (COTS) group to develop systematic, evidence, and experience-based recommendations for the treatment of ocular TB using a modified Delphi technique process. In the first round of Delphi, the group identified clinical scenarios pertinent to ocular TB based on five clinical phenotypes (anterior uveitis, intermediate uveitis, choroiditis, retinal vasculitis, and panuveitis). Using an interactive online questionnaires, guided by background knowledge from published literature, 486 consensus statements for initiating ATT were generated and deliberated amongst 81 global uveitis experts. The median score of five was considered reaching consensus for initiating ATT. The median score of four was tabled for deliberation through Delphi round 2 in a face-to-face meeting. This report describes the methodology adopted and followed through the consensus process, which help elucidate the guidelines for initiating ATT in patients with choroidal TB.
Agrawal R MD FCRS, MBBS GDV, MS AA, MD TI, MD CE, FRCOphth WM, MBBS MS, PhD RD, MS AK, DNB MSI, FRCSEd CSP, MD MP, FRCSGlasg HSL, FRCSEd TS, MD CL, MS BJ, MD NS, MS AM, DNB MP, MD KM, FRCSOphth JN, MD T-TI, DNB BK, MS BS, PhD LR, MD A-DH, MD BB, MD IA, MD GDA, MD HCP, PhD B-AT, PhD G-LJJ, MD AS, MS BR, MS MB, MD ESD, MD TA, MD NS, DNB AM, MD AS, MD VR, MS SR, MD SA, PhD SK, PhD ZM, MRCP KOM, PhD CET, PhD KJH, PhD NQD, FRCSOphth PC, MS GV. Visual Morbidity in Ocular Tuberculosis - Collaborative Ocular Tuberculosis Study (COTS)-1: Report #6. Ocul Immunol Inflamm 2020;:1-9.
Over the last few decades, mesenchymal stem cells-derived exosomes (MSCs-Ex) have attracted a lot of attention as a therapeutic tool in regenerative medicine. Exosomes are extracellular vehicles (EVs) that play important roles in cell-cell communication through various processes such as stress response, senescence, angiogenesis, and cell differentiation. Success in the field of regenerative medicine sparked exploration of the potential use of exosomes as key therapeutic effectors of MSCs to promote tissue regeneration. Various approaches including direct injection, intravenous injection, intraperitoneal injection, oral administration, and hydrogel-based encapsulation have been exploited to deliver exosomes to target tissues in different disease models. Despite significant advances in exosome therapy, it is unclear which approach is more effective for administering exosomes. Herein, we critically review the emerging progress in the applications of exosomes in the form of free or association with hydrogels as therapeutic agents for applications in regenerative medicine.
Purpose: Because preterm birth and retinopathy of prematurity (ROP) are associated with poor visual acuity (VA) and altered foveal development, we evaluated relationships among the central retinal photoreceptors, postreceptor retinal neurons, overlying fovea, and VA in ROP. Methods: We obtained optical coherence tomograms (OCTs) in preterm born subjects with no history of ROP (none; n = 61), ROP that resolved spontaneously without treatment (mild; n = 51), and ROP that required treatment by laser ablation of the avascular peripheral retina (severe; n = 22), as well as in term born control subjects (term; n = 111). We obtained foveal shape descriptors, measured central retinal layer thicknesses, and demarcated the anatomic parafovea using automated routines. In subsets of these subjects, we obtained OCTs eccentrically through the pupil (n = 46) to reveal the fiber layer of Henle (FLH) and obtained adaptive optics scanning light ophthalmograms (AO-SLOs) of the parafoveal cones (n = 34) and measured their spacing and distribution. Results: Both VA and foveal depth decreased with increasing ROP severity (term, none, mild, severe). In severe subjects, foveae were broader than normal and the parafovea was significantly enlarged compared to every other group. The FLH was thinner than normal in mild (but not severe) subjects. VA was associated with foveal depth more than group. Density of parafoveal cones did not differ significantly among groups. Conclusions: Foveal structure is associated with loss of VA in ROP. The preserved FLH in severe (relative to mild) eyes suggests treatment may help cone axon development. The significantly larger parafovea and increased outer nuclear layer (ONL) thickness in ROP hint that some developmental process affecting the photoreceptors is not arrested in ROP but rather is supranormal.
OptrA is an ATP-binding cassette (ABC)-F protein that confers resistance to oxazolidinones and phenicols and can be either plasmid-encoded or chromosomally encoded. Here, we isolated 13 strains possessing a linezolid MIC of ≥4 mg/liter from nursery pigs in swine herds located across Brazil. Genome sequence comparison showed that these strains possess in different genetic contexts occurring in 5 different sequence type backgrounds. The gene invariably occurred in association with an regulator and a gene encoding a hypothetical protein. In some contexts, this genetic island was able to excise and form a covalently closed circle within the cell; this circle appeared to occur in high abundance and to be transmissible by coresident plasmids.
Thousands of frozen, archived tissue samples from the human central nervous system (CNS) are currently available in brain banks. As recent developments in RNA sequencing technologies are beginning to elucidate the cellular diversity present within the human CNS, it is becoming clear that an understanding of this diversity would greatly benefit from deeper transcriptional analyses. Single cell and single nucleus RNA profiling provide one avenue to decipher this heterogeneity. An alternative, complementary approach is to profile isolated, pre-defined cell types and use methods that can be applied to many archived human tissue samples that have been stored long-term. Here, we developed FIN-Seq (Frozen Immunolabeled Nuclei Sequencing), a method that accomplishes these goals. FIN-Seq uses immunohistochemical isolation of nuclei of specific cell types from frozen human tissue, followed by bulk RNA-Sequencing. We applied this method to frozen postmortem samples of human cerebral cortex and retina and were able to identify transcripts, including low abundance transcripts, in specific cell types.
In this study, we extracted the essential oils of the stem, leaf, and flower of Achillea filipendulina, analyzed them, and studied their antibacterial properties. Of 16, 53, and 35 compounds identified in the stem, leaf, and flowers, respectively, only five are present in all three segments of the plant. The essential oil of the stem was mainly composed of neryl acetate, spathulenol, carvacrol, santolina alcohol, and trans-caryophyllene oxide. However, the main identified components of leaf were 1,8-cineole, camphor, ascaridole, trans-isoascaridole, and piperitone oxide and the main components of the flower oil were ascaridole, trans-isoascaridole, 1,8-cineole, p-cymene, and camphor. The extracted oil from different segments demonstrated varying antibacterial properties against both Gram-positive and Gram-negative bacteria, demonstrated by disk, minimum inhibitory concentration, and minimum bactericidal concentration methods. These suggest that the application of all segments of aerial parts of A. filipendulina may have a better therapeutic effect in fighting pathogenic systems.
Cyclodestruction aims to reduce aqueous humor production through the coagulation or destruction of the ciliary body and has been an important treatment choice for glaucoma since the 1930s. The purpose of the current review is to highlight the evidence regarding the safety and efficacy of various cyclodestructive modalities, emphasizing peer-reviewed articles from the last 20 years and the most common variants of these procedures. The review focuses primarily on the two most common variants of transscleral cyclophotocoagulation (TS-CPC), continuous-wave diode cyclophotocoagulation (CW-TSCPC) and MicroPulse diode cyclophotocoagulation (MP-TSCPC) as well as endoscopic cyclophotocoagulation (ECP) and high-intensity focused ultrasound cyclodestruction (HIFU). We believe that the role of cyclodestruction in glaucoma treatment will only continue to expand given the advances in the field, particular with regards to targeted ciliary body destruction and improvement in the safety profile.
: To demonstrate the reliability of conjunctival biopsy analyzed by direct immunofluorescence (DIF) and supplemented with avidin-biotin complex immunoperoxidase (ABC) in diagnosing oMMP, and report therapy response in biopsy-positive patients, particularly when previously biopsy-negative elsewhere.: Retrospective outcomes review of 136 consecutive patients after conjunctival biopsy for suspected oMMP.: Among 136 patients, 66% were diagnosed with oMMP by DIF and 13% via supplemental ABC immunoperoxidase. Sensitivity increased from 79.6% with DIF to 95.6% with supplemental ABC. Among 57 biopsy-positive patients, 77% were in remission at 1-year follow-up and 88% after 2 years. Of 34 previous biopsy-negative but now biopsy-positive patients with a 2-year follow-up, 91% achieved remission, including all 16 diagnosed via DIF and ABC.: Conjunctival biopsy analyzed by histopathology and DIF supplemented by ABC has high reliability for diagnosing oMMP and is a useful tool to use before starting long-term immunomodulatory therapy in a patient with suspected oMMP.
Importance: Vitreous hemorrhage from proliferative diabetic retinopathy can cause loss of vision. The best management approach is unknown. Objective: To compare initial treatment with intravitreous aflibercept vs vitrectomy with panretinal photocoagulation for vitreous hemorrhage from proliferative diabetic retinopathy. Design, Setting, and Participants: Randomized clinical trial at 39 DRCR Retina Network sites in the US and Canada including 205 adults with vison loss due to vitreous hemorrhage from proliferative diabetic retinopathy who were enrolled from November 2016 to December 2017. The final follow-up visit was completed in January 2020. Interventions: Random assignment of eyes (1 per participant) to aflibercept (100 participants) or vitrectomy with panretinal photocoagulation (105 participants). Participants whose eyes were assigned to aflibercept initially received 4 monthly injections. Both groups could receive aflibercept or vitrectomy during follow-up based on protocol criteria. Main Outcomes and Measures: The primary outcome was mean visual acuity letter score (range, 0-100; higher scores indicate better vision) over 24 weeks (area under the curve); the study was powered to detect a difference of 8 letters. Secondary outcomes included mean visual acuity at 4 weeks and 2 years. Results: Among 205 participants (205 eyes) who were randomized (mean [SD] age, 57  years; 115 [56%] men; mean visual acuity letter score, 34.5 [Snellen equivalent, 20/200]), 95% (195 of 205) completed the 24-week visit and 90% (177 of 196, excluding 9 deaths) completed the 2-year visit. The mean visual acuity letter score over 24 weeks was 59.3 (Snellen equivalent, 20/63) (95% CI, 54.9 to 63.7) in the aflibercept group vs 63.0 (Snellen equivalent, 20/63) (95% CI, 58.6 to 67.3) in the vitrectomy group (adjusted difference, -5.0 [95% CI, -10.2 to 0.3], P = .06). Among 23 secondary outcomes, 15 showed no significant difference. The mean visual acuity letter score was 52.6 (Snellen equivalent, 20/100) in the aflibercept group vs 62.3 (Snellen equivalent, 20/63) in the vitrectomy group at 4 weeks (adjusted difference, -11.2 [95% CI, -18.5 to -3.9], P = .003) and 73.7 (Snellen equivalent, 20/40) vs 71.0 (Snellen equivalent, 20/40) at 2 years (adjusted difference, 2.7 [95% CI, -3.1 to 8.4], P = .36). Over 2 years, 33 eyes (33%) assigned to aflibercept received vitrectomy and 34 eyes (32%) assigned to vitrectomy received subsequent aflibercept. Conclusions and Relevance: Among participants whose eyes had vitreous hemorrhage from proliferative diabetic retinopathy, there was no statistically significant difference in the primary outcome of mean visual acuity letter score over 24 weeks following initial treatment with intravitreous aflibercept vs vitrectomy with panretinal photocoagulation. However, the study may have been underpowered, considering the range of the 95% CI, to detect a clinically important benefit in favor of initial vitrectomy with panretinal photocoagulation. Trial Registration: ClinicalTrials.gov Identifier: NCT02858076.
The glycocalyx is a dense and diverse coat of glycans and glycoconjugates responsible for maintaining cell surface integrity and regulating the interaction of cells with the external environment. Transmembrane mucins such as MUC1 and MUC16 comprise a major component of the epithelial glycocalyx and are currently used to monitor disease progression in cancer. At the ocular surface, multiple lines of evidence indicate that abnormal expression of the enzymes responsible for glycan biosynthesis during pathological conditions impairs the glycosylation of transmembrane mucins. It is now becoming clear that these changes contribute to modify the interaction of mucins with galectin-3, a multimeric lectin crucial for preserving the ocular surface epithelial barrier. This review highlights the potential of using the epithelial glycocalyx as a reliable source for the generation of biomarkers to diagnose and monitor ocular surface disease.
The objective of this study was to evaluate which hyperelastic model could best describe the non-linear mechanical behavior of the cornea, in order to characterize the capability of the non-linear model parameters to discriminate structural changes in a damaged cornea. Porcine corneas were used, establishing two different groups: control (non-treated) and NaOH-treated (damaged) corneas (n = 8). NaOH causes a chemical burn to the corneal tissue, simulating a disease associated to structural damage of the stromal layer. Quasi-static uniaxial tensile tests were performed in nasal-temporal direction immediately after preparing corneal strips from the two groups. Three non-linear hyperelastic models (i.e. Hamilton-Zabolotskaya model, Ogden model and Mooney-Rivlin model) were fitted to the stress-strain curves obtained in the tensile tests and statistically compared. The corneas from the two groups showed a non-linear mechanical behavior that was best described by the Hamilton-Zabolotskaya model, obtaining the highest coefficient of determination (R > 0.95). Moreover, Hamilton-Zabolotskaya model showed the highest discriminative capability of the non-linear model parameter (Parameter A) for the tissue structural changes between the two sample groups (p = 0.0005). The present work determines the best hyperelastic model with the highest discriminative capability in description of the non-linear mechanical behavior of the cornea.
AIMS: To compare microaneurysm (MA) counts using ultrawide field colour images (UWF-CI) and ultrawide field fluorescein angiography (UWF-FA). METHODS: Retrospective study including patients with type 1 or 2 diabetes mellitus receiving UWF-FA and UWF-CI within 2 weeks. MAs were manually counted in individual Early Treatment Diabetic Retinopathy Study (ETDRS) and extended UWF zones. Fields with MAs ≥20 determined diabetic retinopathy (DR) severity (0 fields=mild, 1-3=moderate, ≥4=severe). UWF-FA and UWF-CI agreement was determined and UWF-CI DR severity sensitivity analysis adjusting for UWF-FA MA counts performed. RESULTS: In 193 patients (288 eyes), 2.4% had no DR, 29.9% mild non-proliferative DR (NPDR), 32.6% moderate (NPDR), 22.9% severe NPDR and 12.2% proliferative DR. UWF-FA MA counts were 3.5-fold higher (p<0.001) than UWF-CI counts overall, 3.2x-fold higher in ETDRS fields (p<0.001) and 5.3-fold higher in extended ETDRS fields (p<0.001) and higher in type 1 versus type 2 diabetes (p<0.001). In eyes with NPDR on UWF-CI (n=246), UWF-FA images had 1.6x-3.5x more fields with ≥20 MAs (p<0.001). Fair agreement existed between imaging modalities (k=0.221-0.416). In ETDRS fields, DR severity agreement increased from k=0.346 to 0.600 when dividing UWF-FA counts by a factor of 3, followed by rapid decline in agreement thereafter. Total UWF area agreement increased from k=0.317 to 0.565 with an adjustment factor of either 4 or 5. CONCLUSIONS: UWF-FA detects threefold to fivefold more MAs than UWF-CI and identifies 1.6-3.5-fold more fields affecting DR severity. Differences exist at all DR severity levels, thus limiting direct comparison between the modalities. However, correcting UWF-FA MA counts substantially improves DR severity agreement between the modalities.
Importance: Studies have not yet determined whether the distribution of lesions in the retinal periphery alters the association between the severity of diabetic retinopathy (DR) and macular vessel density. Objective: To evaluate the association of DR lesion distribution with optical coherence tomography angiography (OCTA) metrics and DR severity. Design, Setting, and Participants: This cross-sectional observational study was conducted at a tertiary care center for diabetic eye disease among 225 patients with type 1 or 2 diabetes who had undergone imaging between February 15, 2016, and December 31, 2019. Exposures: Optical coherence tomography angiography 3 × 3-mm macular scans and ultra-widefield color imaging. Main Outcomes and Measures: Optical coherence tomography angiography vessel density in the superficial capillary plexus, intermediate capillary plexus, and deep capillary plexus and choriocapillaris flow density. The severity of DR and the predominantly peripheral lesions (PPL) were evaluated from ultra-widefield color imaging. Results: The study evaluated 352 eyes (225 patients; 125 men [55.6%]; mean [SD] age, 52.1 [15.1] years), of which 183 eyes (52.0%) had mild nonproliferative diabetic retinopathy (NPDR), 71 eyes (20.2%) had moderate NPDR, and 98 eyes (27.8%) had severe NPDR or proliferative diabetic retinopathy (PDR). In eyes with no PPL (209 [59.4%]), the mean (SD) vessel density in the superficial capillary plexus (mild NPDR, 38.1% [4.7%]; moderate NPDR, 36.4% [4.6%]; severe NPDR or PDR, 34.1% [4.1%]; P < .001) and the deep capillary plexus (mild NPDR, 45.8% [3.0%]; moderate NPDR, 45.8% [2.2%]; severe NPDR or PDR, 44.5% [1.9%]; P = .002), as well as the mean (SD) choriocapillaris flow density (mild NPDR, 69.7% [6.2%]; moderate NPDR, 67.6% [5.6%]; severe NPDR or PDR, 67.1% [5.6%]; P = .01), decreased with increasing DR severity. These associations remained statistically significant even after correcting for age, signal strength index, spherical equivalent, duration of diabetes, type of diabetes, and correlation between eyes of the same patient. In eyes with PPL (143 [40.6%]), mean (SD) vessel density in the superficial capillary plexus (mild NPDR, 34.1% [4.1%]; moderate NPDR, 35.2% [4.1%]; severe NPDR or PDR, 36.0% [4.3%]; P = .42) and the deep capillary plexus (mild NPDR, 44.5% [1.7%]; moderate NPDR, 45.4% [1.4%]; severe NPDR or PDR, 44.9% [1.5%]; P = .81), as well as the mean (SD) choriocapillaris flow density (mild NPDR, 67.1% [5.6%]; moderate NPDR, 69.3% [4.6%]; severe NPDR or PDR, 68.3% [5.6%]; P = .49), did not appear to change with increasing DR severity. Conclusions and Relevance: These results suggest that central retinal vessel density is associated with DR severity in eyes without, but not with, PPL. These findings suggest a potential need to stratify future optical coherence tomography angiography studies of eyes with DR by the presence or absence of PPL. If DR onset and worsening are associated with the location of retinal nonperfusion, assessment of global retinal nonperfusion using widefield angiography may improve the ability to evaluate DR severity and risk of DR worsening over time.