2021

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Schill HM, Wolfe JM, Brady TF. Relationships between expertise and distinctiveness: Abnormal medical images lead to enhanced memory performance only in experts. Mem Cognit 2021;49(6):1067-1081.Abstract
Memories are encoded in a manner that depends on our knowledge and expectations ("schemas"). Consistent with this, expertise tends to improve memory: Experts have elaborated schemas in their domains of expertise, allowing them to efficiently represent information in this domain (e.g., chess experts have enhanced memory for realistic chess layouts). On the other hand, in most situations, people tend to remember abnormal or surprising items best-those that are also rare or out-of-the-ordinary occurrences (e.g., surprising-but not random-chess board configurations). This occurs, in part, because such images are distinctive relative to other images. In the current work, we ask how these factors interact in a particularly interesting case-the domain of radiology, where experts actively search for abnormalities. Abnormality in mammograms is typically focal but can be perceived in the global "gist" of the image. We ask whether, relative to novices, expert radiologists show improved memory for mammograms. We also test for any additional advantage for abnormal mammograms that can be thought of as unexpected or rare stimuli in screening. We find that experts have enhanced memory for focally abnormal images relative to normal images. However, radiologists showed no memory benefit for images of the breast that were not focally abnormal, but were only abnormal in their gist. Our results speak to the role of schemas and abnormality in expertise; the necessity for spatially localized abnormalities versus abnormalities in the gist in enhancing memory; and the nature of memory and decision-making in radiologists.
Schoemaker D, Velilla L, Zuluaga Y, Baena A, Ospina C, Bocanegra Y, Alvarez S, Ochoa-Escudero M, Guzmán-Vélez E, Martinez J, Lopera F, Arboleda-Velasquez JF, Quiroz YT. Global Cardiovascular Risk Profile and Cerebrovascular Abnormalities in Presymptomatic Individuals with CADASIL or Autosomal Dominant Alzheimer's Disease. J Alzheimers Dis 2021;Abstract
BACKGROUND: Cardiovascular risk factors increase the risk of developing dementia, including Alzheimer's disease and vascular dementia. OBJECTIVE: Studying individuals with autosomal dominant mutations leading to the early onset of dementia, this study examines the effect of the global cardiovascular risk profile on early cognitive and neuroimaging features of Alzheimer's disease and vascular dementia. METHODS: We studied 85 non-demented and stroke-free individuals, including 20 subjects with Presenilin1 (PSEN1) E280A mutation leading to the early onset of autosomal dominant Alzheimer's disease (ADAD), 20 subjects with NOTCH3 mutations leading to cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and to the early onset of vascular dementia, and 45 non-affected family members (non-carriers). All subjects underwent clinical and neuropsychological evaluations and an MRI. The global cardiovascular risk profile was estimated using the office-based Framingham Cardiovascular Risk Profile (FCRP) score. RESULTS: In individuals with CADASIL, a higher FCRP score was associated with a reduced hippocampal volume (B = -0.06, p <  0.05) and an increased severity of cerebral microbleeds (B = 0.13, p <  0.001), lacunes (B = 0.30, p <  0.001), and perivascular space enlargement in the basal ganglia (B = 0.50, p <  0.05). There was no significant association between the FCRP score and neuroimaging measures in ADAD or non-carrier subjects. While the FCRP score was related to performance in executive function in non-carrier subjects (B = 0.06, p <  0.05), it was not significantly associated with cognitive performance in individuals with CADASIL or ADAD. CONCLUSION: Our results suggest that individuals with CADASIL and other forms of vascular cognitive impairment might particularly benefit from early interventions aimed at controlling cardiovascular risks.
Schoemaker D, Arboleda-Velasquez JF. NOTCH3 SIGNALING AND AGGREGATION AS TARGETS FOR THE TREATMENT OF CADASIL AND OTHER NOTCH3-ASSOCIATED SMALL VESSEL DISEASE. Am J Pathol 2021;Abstract
Mutations in the NOTCH3 gene can lead to small vessel disease in humans, including the well-characterized cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a condition caused by NOTCH3 mutations altering the number of cysteine residues in the extracellular domain of Notch3. Growing evidence indicates that other mutations in NOTCH3, including cysteine-sparing missense mutations, or frameshift and premature stop codons, can lead to small vessel disease phenotypes of variable severity or penetrance. There are currently no disease-modifying therapies for small vessel disease, including those associated with NOTCH3 mutations. A deeper understanding of underlying molecular mechanisms and clearly defined targets are needed to promote the development of therapies. This review discusses two key pathophysiological mechanisms believed to contribute to the emergence and progression of small vessel disease associated with NOTCH3 mutations: abnormal Notch3 aggregation and aberrant Notch3 signaling. This review offers a summary of the literature supporting and challenging the relevance of these mechanisms, together with an overview of available preclinical experiments derived from these mechanisms. Through the review, knowledge gaps and future research directions are highlighted. In view of recent evidence demonstrating the relatively high frequency of NOTCH3 mutations in the population, and their potential role in promoting small vessel disease, progress in the development of therapies for NOTCH3 -associated small vessel disease is urgently needed.
Serafino M, Granet DB, Kushner BJ, Dagi LR, Kekunnaya R, Nucci P, Kreatsoulas C. Definition of successful outcomes after surgery for each type of strabismus: a Delphi study. J AAPOS 2021;Abstract
BACKGROUND: The Delphi process has been widely used to delineate guidelines for the treatment of disorders for which there is little or no evidence in the published literature. The purpose of this study was to use the Delphi process to identify areas of consensus and disagreement on the definition of success after surgery for each type of strabismus. METHODS: Two rounds of electronic questionnaires were sent to 28 members of the Strabismus Success Definition Delphi Study Group. For the first round, responses to 70 questions were captured as agree (= 1) and disagree (= 2). For round 2, a total of 89 questions were captured on a Likert scale ranging from 1 (strongly disagree) to 7 (strongly agree). Consensus was determined a priori at 85%. RESULTS: In both the first and second rounds, inter-rater agreement of 85% consensus was reached for only 20% of questions. Intra-rater agreement per question was low, with κ values ranging from -0.11 to 0.62. Intra-rater agreement was also low among themes, ranging from poor to fair agreement: κ = 0.25 for motor, κ = 0.28 for sensory, and κ = 0.35 for follow-up. CONCLUSIONS: This study highlights consensus areas that could be considered by researchers in designing studies and identifies areas where lack of consensus indicates that further research is needed.
Seto B, Singh MK, Lemire CA, Arroyo JG. Anterior versus posterior endoscopic cyclophotocoagulation: comparison of indications, populations, and outcomes. Int Ophthalmol 2021;Abstract
PURPOSE: To examine how indications, patient characteristics, and outcomes differ between anterior and posterior approaches of endoscopic cyclophotocoagulation (ECP) in the treatment of glaucoma. METHODS: This is a retrospective chart review of 9 anterior and 20 posterior ECP cases (n = 29). RESULTS: Posterior ECP cases were typically associated with a dramatic increase in intraocular pressure (IOP), whereas the anterior ECP was associated with chronically elevated pressures. The initial IOPs in mm Hg of posterior ECP cases (26.8 non-NVG; 35.2 NVG) were much greater than anterior ECP cases (17.8), and a greater overall reduction in IOP was observed in the posterior versus anterior ECP cases (10.3 posterior non-NVG; 21.3 posterior NVG; 3.6 anterior, P < .001). With procedural success defined as 6-month post-operative IOP falling within normal ranges and a decrease in either IOP or number of prescribed glaucoma medications, the success rate of ECP was 92% for posterior NVG, 89% for anterior and 75% for posterior non-NVG cases (P = .34), similar to the previous literature. Of the four unsuccessful cases, two resulted in a normal IOP but lacked a drop in pressure or reduction in medication burden, one resulted in a 6-point drop in IOP but remained at 23 mm Hg, and one resulted in phthisis bulbi (3%) from an initial pressure above 40 mm Hg. CONCLUSION: Endoscopic cyclophotocoagulation is an effective and safe procedure for severe glaucoma cases from both an anterior and posterior approach. Ophthalmologists should consider this procedure as part of their glaucoma treatment arsenal.
Shanbhag SS, Shih G, Bispo PJM, Chodosh J, Jacobs DS, Saeed HN. Diphtheroids as Corneal Pathogens in Chronic Ocular Surface Disease in Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis. Cornea 2021;40(6):774-779.Abstract
PURPOSE: To characterize diphtheroid corneal infections in eyes in the chronic phase of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN). METHODS: Observational case series. RESULTS: Four eyes of 3 patients were included in this review. Each eye presented with persistent corneal epithelial defect with corneal thinning in the chronic phase of SJS/TEN. None of the epithelial defects were associated with stromal infiltration. The corneas were cultured at the time of workup of persistent epithelial defect (3 eyes) or at time of tectonic penetrating keratoplasty after perforation (1 eye). Cultures yielded abundant growth of Corynebacterium spp., including Corynebacterium jeikeium (n = 2), Corynebacterium glucuronolyticum (n = 1), and a multidrug-resistant Corynebacterium striatum isolate (n = 1). The ocular surface was stabilized with surgical intervention (1 eye) or with introduction of fortified topical antibiotic based on laboratory identification and susceptibility testing of the isolated organisms (3 eyes). Numerous risk factors for microbial keratitis were present in all 4 eyes. CONCLUSIONS: In eyes with a persistent corneal epithelial defect in the chronic phase of SJS/TEN, even in the absence of an infiltrate, corneal culture should be undertaken. Recognition and treatment of Corynebacterium spp. as opportunistic pathogens may lead to favorable outcomes in cases of clinically sterile ulceration during the chronic phase of SJS/TEN.
Sharif F, Tayebi B, Buzsáki G, Royer S, Fernandez-Ruiz A. Subcircuits of Deep and Superficial CA1 Place Cells Support Efficient Spatial Coding across Heterogeneous Environments. Neuron 2021;109(2):363-376.e6.Abstract
The hippocampus is thought to guide navigation by forming a cognitive map of space. Different environments differ in geometry and the availability of cues that can be used for navigation. Although several spatial coding mechanisms are known to coexist in the hippocampus, how they are influenced by various environmental features is not well understood. To address this issue, we examined the spatial coding characteristics of hippocampal neurons in mice and rats navigating in different environments. We found that CA1 place cells located in the superficial sublayer were more active in cue-poor environments and preferentially used a firing rate code driven by intra-hippocampal inputs. In contrast, place cells located in the deep sublayer were more active in cue-rich environments and used a phase code driven by entorhinal inputs. Switching between these two spatial coding modes was supported by the interaction between excitatory gamma inputs and local inhibition.
Sharifi S, Islam MM, Sharifi H, Islam R, Huq TN, Nilsson PH, Mollnes TE, Tran KD, Patzer C, Dohlman CH, Patra HK, Paschalis EI, Gonzalez-Andrades M, Chodosh J. Electron Beam Sterilization of Poly(Methyl Methacrylate)-Physicochemical and Biological Aspects. Macromol Biosci 2021;21(4):e2000379.Abstract
Electron beam (E-beam) irradiation is an attractive and efficient method for sterilizing clinically implantable medical devices made of natural and/or synthetic materials such as poly(methyl methacrylate) (PMMA). As ionizing irradiation can affect the physicochemical properties of PMMA, understanding the consequences of E-beam sterilization on the intrinsic properties of PMMA is vital for clinical implementation. A detailed assessment of the chemical, optical, mechanical, morphological, and biological properties of medical-grade PMMA after E-beam sterilization at 25 and 50 kiloGray (kGy) is reported. Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry studies indicate that E-beam irradiation has minimal effect on the chemical properties of the PMMA at these doses. While 25 kGy irradiation does not alter the mechanical and optical properties of the PMMA, 50 kGy reduces the flexural strength and transparency by 10% and 2%, respectively. Atomic force microscopy demonstrates that E-beam irradiation reduces the surface roughness of PMMA in a dose dependent manner. Live-Dead, AlamarBlue, immunocytochemistry, and complement activation studies show that E-beam irradiation up to 50 kGy has no adverse effect on the biocompatibility of the PMMA. These findings suggest that E-beam irradiation at 25 kGy may be a safe and efficient alternative for PMMA sterilization.
Sharifi S, Sharifi H, Guild C, Islam MM, Tran KD, Patzer C, Dohlman CH, Paschalis EI, Gonzalez-Andrades M, Chodosh J. Toward electron-beam sterilization of a pre-assembled Boston keratoprosthesis. Ocul Surf 2021;20:176-184.Abstract
PURPOSE: To evaluate the effects of electron-beam (E-beam) irradiation on the human cornea and the potential for E-beam sterilization of Boston keratoprosthesis (BK) devices when pre-assembled with a donor cornea prior to sterilization. METHODS: Human donor corneas and corneas pre-assembled in BK devices were immersed in recombinant human serum albumin (rHSA) media and E-beam irradiated at 25 kGy. Mechanical (tensile strength and modulus, and compression modulus), chemical, optical, structural, and degradation properties of the corneal tissue after irradiation and after 6 months of preservation were evaluated. RESULTS: The mechanical evaluation showed that E-beam irradiation enhanced the tensile and compression moduli of human donor corneas, with no impact on their tensile strength. By chemical and mechanical analysis, E-beam irradiation caused a minor degree of crosslinking between collagen fibrils. No ultrastructural changes due to E-beam irradiation were observed. E-beam irradiation slightly increased the stability of the cornea against collagenase-induced degradation and had no impact on glucose diffusion. The optical evaluation showed transparency of the cornea was maintained. E-beam irradiated corneal tissues and BK-cornea pre-assembled devices were stable for 6 months after room-temperature preservation. CONCLUSIONS: E-beam irradiation generated no detrimental effects on the corneal tissues or BK-cornea pre-assembled devices and improved native properties of the corneal tissue, enabling prolonged preservation at room temperature. The pre-assembly of BK in a donor cornea, followed by E-beam irradiation, offers the potential for an off-the-shelf, ready to implant keratoprosthesis device.
Sharon Y, Anesi SD, Martinez CE, Huang AJW, Foster CS, Chu DS. Repository Corticotropin Injection as an Alternative Treatment for Refractory Ocular Mucous Membrane Pemphigoid. Cornea 2021;Abstract
PURPOSE: The purpose of this study was to report the clinical course and outcome of patients with refractory ocular mucous membrane pemphigoid (MMP) treated by repository corticotropin injection (RCI). METHODS: Patients with biopsy-proven ocular MMP treated with RCI from 3 tertiary medical centers were evaluated. Medical records between January 2013 and January 2021 were reviewed and deidentified to retrieve relevant disease-related data. Primary outcome measures included conjunctival inflammatory activity, change in Foster clinical conjunctival scarring staging after RCI treatment, and the development of ocular and systemic complications. RESULTS: Included were 15 patients (10 women and 5 men; 36-95 yrs of age) with a mean follow-up of 4.5 years. Most of the patients (80%) had Foster stage 3 at presentation, and all patients had active MMP. Each patient had failed to respond to at least 1 immunomodulatory drug during the follow-up, and 9 (60%) patients had treatment failure of at least 2 other agents before the use of RCI. The mean duration of RCI treatment was 21 months (range, 3-54 mo). Foster stage did not change in any of the 15 patients at the last follow-up. Nine patients continued RCI therapy at the last follow-up, and in all of them, the disease activity of MMP was well controlled. No serious adverse events because of RCI were documented during the follow-up in any treated patient. CONCLUSIONS: RCI may serve as an alternative or an adjunctive treatment in patients with severe and refractory ocular MMP. Treatment with RCI seems to be safe and well-tolerated.
Shoji MK, Cousins CC, Saini C, Silva RNE, Wang M, Brauner SC, Greenstein SH, Pasquale LR, Shen LQ. Paired Optic Nerve Microvasculature and Nailfold Capillary Measurements in Primary Open-Angle Glaucoma. Transl Vis Sci Technol 2021;10(7):13.Abstract
Purpose: To assess microvascular beds in the optic nerve head (ONH), peripapillary tissue, and the nailfold in patients with primary open-angle glaucoma (POAG) versus controls. Methods: Patients with POAG (n = 22) and controls (n = 12) underwent swept-source optical coherence tomography angiography of ophthalmic microvasculature and nailfold video capillaroscopy of the hand. The main outcomes were vessel density (VD) and blood flow of the ONH, the peripapillary and the nailfold microvasculatures. Results: Patients with POAG were younger than controls (63.5 ± 9.4 vs. 69.9 ± 6.5 years, P = 0.03). Deep ONH VD and blood flow were lower in patients with POAG than controls (39.1% ± 3.5% vs. 43.8% ± 5.7%; 37.8% ± 5.3% vs. 46.0% ± 7.8%, respectively, P < 0.02 for both); similar results were observed with peripapillary VD (37.9 ± 2.6%, 43.4 ± 7.6%, respectively, P = 0.03). Nailfold capillary density and blood flow were lower in patients with POAG than controls (8.8 ± 1.0 vs. 9.8 ± 0.9 capillaries/mm; 19.9 ± 9.4 vs. 33.7 ± 9.8 pL/s, respectively; P < 0.009 for both). After adjusting for age and gender, deep ONH VD and blood flow, peripapillary VD, and nailfold capillary blood flow were lower in POAG than controls (β = -0.04, -0.07, -0.05, -13.19, respectively, P ≤ 0.046 for all). Among all participants, there were positive correlations between deep ONH and nailfold capillary blood flow (Pearson's correlation coefficient r = 0.42, P = 0.02), peripapillary and nailfold capillary density (r = 0.43, P = 0.03), and peripapillary and nailfold capillary blood flow (r = 0.49, P = 0.01). Conclusions: Patients with POAG demonstrated morphologic and hemodynamic alterations in both ophthalmic and nailfold microvascular beds compared to controls. Translational Relevance: The concomitant abnormalities in nailfold capillaries and relevant ocular vascular beds in POAG suggest that the microvasculature may be a target for POAG treatment.
Shoshany TN, Chinn RN, Staffa SJ, Bishop K, Michalak S, Hunter DG. Identifying Characteristics Predictive of Lost-to-follow-up (LTFU) Status in Amblyopia. Am J Ophthalmol 2021;Abstract
PURPOSE: To identify demographic and disease-related characteristics predictive of LTFU status in amblyopia treatment and create a risk model for predicting LTFU status. DESIGN: Retrospective cohort study METHODS: Setting: Single center, ophthalmology department at Boston Children's Hospital (BCH). PATIENTS: 2037 patients treated for amblyopia at BCH between 2010-2014. OBSERVATION PROCEDURE: LTFU was defined as patients who did not return after initial visit, excluding those who came for second opinion. Multiple variables were tested for association with LTFU status. OUTCOME MEASURE: Odds ratio of LTFU risk associated with each variable. Multivariate logistic regression was used to create a risk score for predicting LTFU status. RESULTS: A large proportion of patients (23%) were LTFU after first visit. Older age, non-white race, lack of insurance, previous glasses or atropine treatment, and longer requested follow-up intervals were independent predictors of LTFU status. A multivariable risk score was created to predict probability of LTFU (AUC 0.68). CONCLUSIONS: Our comprehensive amblyopia database allows us to predict which patients are more likely to be LTFU after baseline visit, and develop strategies to mitigate these effects. These findings may help with practice efficiency and improve patient outcomes in the future by transitioning these analyses to an electronic medical record that could be programmed to provide continually updated decision support for individual patients based on large datasets.
Shroff S, Gu SZ, Vardhan S A, Mani I, Aziz K, P N, Datta D, Friedman DS. Screening first-degree relatives of glaucoma patients reveals barriers to participation. Br J Ophthalmol 2021;Abstract
PURPOSE: To report the results of a glaucoma screening campaign targeting first-degree relatives of glaucoma patients in South India. METHODS: 1598 glaucoma patients were contacted via letter or letter and phone call and asked to bring their siblings and children to a glaucoma screening. Participants underwent standardised eye examinations and completed questionnaires that assessed barriers to participation and awareness of glaucoma risk. Two-proportion z-tests were used to compare categorical data. Costs associated with the screening were recorded. RESULTS: 206 probands (12.9%) attended the screening along with 50 siblings and children. Probands were nearly twice as likely to attend if they had been contacted via both letter and phone call rather than letter only. Over half of probands reported that their relatives could not participate because they did not live in the region, and one-fifth reported that their relatives had other commitments. Fifty-eight per cent of the siblings and children who attended did not know that they were at increased risk for glaucoma due to their family history, and 32.0% did not know that the relative who had invited them to the screening had glaucoma. Thirteen siblings and children (26.0% of those who attended) were found to have findings concerning for glaucoma. The average cost per first-degree relative who was screened was INR2422 (£26). CONCLUSION: Participation in this glaucoma screening campaign was poor. The major barrier to participation was distance from the screening site and associated indirect costs. Better strategies for bringing first-degree relatives in for examinations are needed.
Shuldiner SR, Boland MV, Ramulu PY, De Moraes GC, Elze T, Myers J, Pasquale L, Wellik S, Yohannan J. Predicting eyes at risk for rapid glaucoma progression based on an initial visual field test using machine learning. PLoS One 2021;16(4):e0249856.Abstract
OBJECTIVE: To assess whether machine learning algorithms (MLA) can predict eyes that will undergo rapid glaucoma progression based on an initial visual field (VF) test. DESIGN: Retrospective analysis of longitudinal data. SUBJECTS: 175,786 VFs (22,925 initial VFs) from 14,217 patients who completed ≥5 reliable VFs at academic glaucoma centers were included. METHODS: Summary measures and reliability metrics from the initial VF and age were used to train MLA designed to predict the likelihood of rapid progression. Additionally, the neural network model was trained with point-wise threshold data in addition to summary measures, reliability metrics and age. 80% of eyes were used for a training set and 20% were used as a test set. MLA test set performance was assessed using the area under the receiver operating curve (AUC). Performance of models trained on initial VF data alone was compared to performance of models trained on data from the first two VFs. MAIN OUTCOME MEASURES: Accuracy in predicting future rapid progression defined as MD worsening more than 1 dB/year. RESULTS: 1,968 eyes (8.6%) underwent rapid progression. The support vector machine model (AUC 0.72 [95% CI 0.70-0.75]) most accurately predicted rapid progression when trained on initial VF data. Artificial neural network, random forest, logistic regression and naïve Bayes classifiers produced AUC of 0.72, 0.70, 0.69, 0.68 respectively. Models trained on data from the first two VFs performed no better than top models trained on the initial VF alone. Based on the odds ratio (OR) from logistic regression and variable importance plots from the random forest model, older age (OR: 1.41 per 10 year increment [95% CI: 1.34 to 1.08]) and higher pattern standard deviation (OR: 1.31 per 5-dB increment [95% CI: 1.18 to 1.46]) were the variables in the initial VF most strongly associated with rapid progression. CONCLUSIONS: MLA can be used to predict eyes at risk for rapid progression with modest accuracy based on an initial VF test. Incorporating additional clinical data to the current model may offer opportunities to predict patients most likely to rapidly progress with even greater accuracy.
Silpa-Archa S, Ittharat W, Chotcomwongse P, Preble JM, Foster SC. Analysis of Three-Dimensional Choroidal Volume with Enhanced Depth Imaging Findings in Patients with Recurrent Vogt-Koyanagi-Harada Disease. Curr Eye Res 2021;46(7):1010-1017.Abstract
Purpose: To demonstrate changes in three-dimensional choroidal volume with enhanced depth imaging optical coherence tomography (EDI-OCT) in patients with recurrent stage of Vogt-Koyanagi-Harada disease (VKH).Materials and Methods: This prospective comparative case series included 9 patients with recurrent VKH, 10 patients with quiet VKH, and 15 healthy controls after sample size was calculated. All VKH cases with recurrences underwent raster scanning with EDI-OCT at active and inactive stages of the disease.Results: All choroidal parameters in the active stage significantly reduced when the inflammation subsided: total choroidal volume (P = .02), central choroidal volume (P = .01), central choroidal thickness (P = .03). The changes in central choroidal volume over the resolution phase were more pronounced than the changes in central choroidal thickness in 56% of cases. Two cases presenting with only subclinical posterior segment recurrence had their choroidal parameters recovered after prompt treatment.Conclusions: In the recurrent stage of VKH, alteration in choroidal volume was evident by EDI-OCT even in an absence of anterior segment inflammation. Central choroidal volume may serve as a biomarker for detecting choroidal morphological change.
Silva RNE, Chiou CA, Wang M, Devlin J, Li D, Lovelace S, Wang H, Greenstein SH, Brauner SC, Shen LQ. Quantification of the Peripapillary Microvasculature in Eyes with Glaucomatous Paracentral Visual Field Loss. Ophthalmol Glaucoma 2021;4(3):286-294.Abstract
PURPOSE: To quantify abnormalities in the peripapillary microvasculature in eyes with primary open-angle glaucoma (POAG) and paracentral visual field (VF) loss. DESIGN: Prospective, cross-sectional study. PARTICIPANTS: Thirty-three POAG patients, including 15 with paracentral VF loss and 18 with peripheral VF loss, and 31 control participants underwent swept-source OCT angiography (OCTA) of the peripapillary region. METHODS: The POAG groups were matched by VF mean deviation (MD). The peripapillary microvasculature from the internal limiting membrane to the retinal nerve fiber layer (RNFL) interface was quantified within a 0.70-mm annulus around Bruch's membrane opening after removal of large vessels. Both vessel density (VD) and the integrated OCTA by ratio analysis signal (IOS) suggestive of flow were measured. Regional VD and IOS were measured from the affected hemisphere corresponding to the VF hemifield of more severe loss, which was used to calculate the paracentral total deviation (PaTD), or total deviation within the central 10°. One eye per participant was included. MAIN OUTCOME MEASURES: Difference in peripapillary OCTA measurements between paracentral and peripheral VF loss groups and correlation of peripapillary VD and IOS with PaTD. RESULTS: The POAG groups had matched VF MD (-3.1 ± 2.5 dB paracentral vs. -2.3 ± 2.0 dB peripheral; P = 0.31), did not differ in average RNFL thickness (71.1 ± 14.7 μm vs. 78.1 ± 15.0 μm; P = 0.55), but differed in age (59.2 ± 9.6 years paracentral vs. 67.4 ± 6.6 years peripheral; P = 0.02). Compared with control participants, both paracentral and peripheral VF loss groups showed reduced VD (P < 0.001 and P = 0.009, respectively) and IOS (P < 0.001 and P = 0.01, respectively) in the affected hemisphere. Compared with POAG eyes with peripheral VF loss, the paracentral group showed reduced peripapillary VD (38.0 ± 2.0%, 35.0 ± 2.2%, respectively; P = 0.001) and IOS (44.3 ± 3.1%, 40.4 ± 4.0%, respectively; P = 0.02) in the affected hemisphere. Among all POAG eyes, peripapillary VD and IOS of the affected hemisphere correlated significantly with functional measurement of paracentral loss (PaTD, r = 0.40, P = 0.02; r = 0.45, P = 0.008; respectively). These correlations remained significant after adjusting for age (r = 0.41, P = 0.02; r = 0.47, P = 0.01; respectively). CONCLUSIONS: Regional peripapillary microvasculature showed decreased VD and flow in POAG with paracentral loss, supporting its importance in this glaucoma subtype.
Simpson FC, McTiernan CD, Islam MM, Buznyk O, Lewis PN, Meek KM, Haagdorens M, Audiger C, Lesage S, Gueriot F-X, Brunette I, Robert M-C, Olsen D, Koivusalo L, Liszka A, Fagerholm P, Gonzalez-Andrades M, Griffith M. Collagen analogs with phosphorylcholine are inflammation-suppressing scaffolds for corneal regeneration from alkali burns in mini-pigs. Commun Biol 2021;4(1):608.Abstract
The long-term survival of biomaterial implants is often hampered by surgery-induced inflammation that can lead to graft failure. Considering that most corneas receiving grafts are either pathological or inflamed before implantation, the risk of rejection is heightened. Here, we show that bioengineered, fully synthetic, and robust corneal implants can be manufactured from a collagen analog (collagen-like peptide-polyethylene glycol hybrid, CLP-PEG) and inflammation-suppressing polymeric 2-methacryloyloxyethyl phosphorylcholine (MPC) when stabilized with the triazine-based crosslinker 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. The resulting CLP-PEG-MPC implants led to reduced corneal swelling, haze, and neovascularization in comparison to CLP-PEG only implants when grafted into a mini-pig cornea alkali burn model of inflammation over 12 months. Implants incorporating MPC allowed for faster nerve regeneration and recovery of corneal sensation. CLP-PEG-MPC implants appear to be at a more advanced stage of regeneration than the CLP-PEG only implants, as evidenced by the presence of higher amounts of cornea-specific type V collagen, and a corresponding decrease in the presence of extracellular vesicles and exosomes in the corneal stroma, in keeping with the amounts present in healthy, unoperated corneas.
Singh RB, Gupta P, Kartik A, Farooqui N, Singhal S, Shergill S, Singh KP, Agarwal A. Ocular Manifestations of Neuronal Ceroid Lipofuscinoses. Semin Ophthalmol 2021;:1-14.Abstract
Neuronal ceroid lipofuscinoses (NCLs) are a group of rare neurodegenerative storage disorders associated with devastating visual prognosis, with an incidence of 1/1,000,000 in the United States and comparatively higher incidence in European countries. The pathophysiological mechanisms causing NCLs occur due to enzymatic or transmembrane defects in various sub-cellular organelles including lysosomes, endoplasmic reticulum, and cytoplasmic vesicles. NCLs are categorized into different types depending upon the underlying cause i.e., soluble lysosomal enzyme deficiencies or non-enzymatic deficiencies (functions of identified proteins), which are sub-divided based on an axial classification system. In this review, we have evaluated the current evidence in the literature and reported the incidence rates, underlying mechanisms and currently available management protocols for these rare set of neuroophthalmological disorders. Additionally, we also highlighted the potential therapies under development that can expand the treatment of these rare disorders beyond symptomatic relief.
Singh N, Singh R, Bowen RC, Abdel-Rahman MH, Singh AD. Uveal Melanoma in BAP1 Tumor Predisposition Syndrome: Estimation of Risk. Am J Ophthalmol 2021;224:172-177.Abstract
PURPOSE: To estimate point prevalence of uveal melanoma in the patients with germline BAP1 pathogenic variant. DESIGN: Cohort study with risk assessment using Bayesian analysis. METHODS: The point prevalence estimate was obtained by Bayes's rule of reverse conditional probabilities. The probability of uveal melanoma given that BAP1 mutation exists was derived from the prevalence of uveal melanoma, prevalence of germline BAP1 pathogenic variants, and the probability of germline BAP1 pathogenic variant given that uveal melanoma is present. Confidence intervals (CIs) for each variable were calculated as the mean of Bernoulli random variables and for the risk estimate, by the delta method. The age at diagnosis and the gender of the uveal melanoma patients with BAP1 germline pathogenic variants obtained from previous publications or from authors' unpublished cohort was compared with those in the Surveillance, Epidemiology, and End Results (SEER) database. RESULTS: The point prevalence of uveal melanoma in patients with the germline BAP1 pathogenic variants in the US population was estimated to be 2.8% (95% CI, 0.88%-4.81%). In the SEER database, the median age at diagnosis of uveal melanomas was 63 (range 3-99 years) with a male-to-female ratio of 1.01:1. In comparison, uveal melanoma cases with BAP1 germline pathogenic variants from the US population (n = 27) had a median age at diagnosis of 50.5 years (range 16-71). CONCLUSIONS: Quantification of the risk of developing uveal melanoma can enhance counseling regarding surveillance in patients with germline BAP1 pathogenic variant.
Singh RB, Liu L, Yung A, Anchouche S, Mittal SK, Blanco T, Dohlman TH, Yin J, Dana R. Ocular redness - II: Progress in development of therapeutics for the management of conjunctival hyperemia. Ocul Surf 2021;21:66-77.Abstract
Conjunctival hyperemia is one of the most common causes for visits to primary care physicians, optometrists, ophthalmologists, and emergency rooms. Despite its high incidence, the treatment options for patients with conjunctival hyperemia are restricted to over-the-counter drugs that provide symptomatic relief due to short duration of action, tachyphylaxis and rebound redness. As our understanding of the immunopathological pathways causing conjunctival hyperemia expands, newer therapeutic targets are being discovered. These insights have also contributed to the development of animal models for mimicking the pathogenic changes in microvasculature causing hyperemia. Furthermore, this progress has catalyzed the development of novel therapeutics that provide efficacious, long-term relief from conjunctival hyperemia with minimal adverse effects.

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