Publications

2020

Brazile B, Yang B, Waxman S, Lam P, Voorhees A, Hua Y, Loewen R, Loewen N, Rizzo J, Jakobs T, Sigal I. Lamina Cribrosa Capillaries Straighten as Intraocular Pressure Increases. Invest Ophthalmol Vis Sci. 2020;61(12):2.
Purpose: The purpose of this study was to visualize the lamina cribrosa (LC) capillaries and collagenous beams, measure capillary tortuosity (path length over straight end-to-end length), and determine if capillary tortuosity changes when intraocular pressure (IOP) increases. Methods: Within 8 hours of sacrifice, 3 pig heads were cannulated via the external ophthalmic artery, perfused with PBS to remove blood, and then perfused with a fluorescent dye to label the capillaries. The posterior pole of each eye was mounted in a custom-made inflation chamber for control of IOP with simultaneous imaging. Capillaries and collagen beams were visualized with structured light illumination enhanced imaging at IOPs from 5 to 50 mm Hg at each 5 mm Hg increment. Capillary tortuosity was measured from the images and paired two-sample t-tests were used to assess for significant changes in relation to changes in IOP. Results: Capillaries were highly tortuous at 15 mm Hg (up to 1.45). In all but one eye, tortuosity decreased significantly as IOP increased from 15 to 25 mm Hg (P < 0.01), and tortuosity decreased significantly in every eye as IOP increased from 15 to 40 mm Hg (P < 0.01). In only 16% of capillaries, tortuosity increased with elevated IOP. Capillaries had a surprisingly different topology from the collagen beams. Conclusions: Although high capillary tortuosity is sometimes regarded as potentially problematic because it can reduce blood flow, LC capillary tortuosity may provide slack that mitigates against reduced flow and structural damage caused by excessive stretch under elevated IOP. We speculate that low capillary tortuosity could be a risk factor for damage under high IOP.
Ospina C, Arboleda-Velasquez J, Aguirre-Acevedo DC, Zuluaga-Castaño Y, Velilla L, Garcia G, Quiroz Y, Lopera F. Genetic and nongenetic factors associated with CADASIL: A retrospective cohort study. J Neurol Sci. 2020;419:117178.
OBJECTIVE: To explore the role of cardiovascular risk factors and the different NOTCH-3 mutations to explain the variability observed in the clinical presentation of CADASIL. METHODS: This was a retrospective cohort study of 331 individuals, 90 were carriers of four mutations in the NOTCH3 gene. These four mutations are the ones identified in our region from the genetic evaluation of probands. Cox proportional hazards models were fitted to estimate the effect of genetic and cardiovascular factors on the onset of migraine, first stroke, and dementia. Competing risk regression models considered death as risk. RESULTS: Noncarriers (healthy controls from the same families without NOTCH3 mutations) and NOTCH3 mutation carriers had similar frequencies for all cardiovascular risk factors. Diabetes (SHR 2.74, 95% CI 1.52-4.94) was associated with a younger age at onset of strokes among carriers. Additionally, a genotype-phenotype relationship was observed among C455R mutation carriers, with higher frequency of migraines (100%), younger age at onset of migraine (median age 7 years, IQR 8) and strokes (median age 30.5 years, IQR 26). Moreover, fewer carriers of the R141C mutation exhibited migraines (20%), and it was even lower than the frequency observed in the noncarrier group (44.8%). CONCLUSIONS: This study characterizes extended family groups, allowing us a comparison in the genotype-phenotype. The results suggest a complex interplay of genetic and cardiovascular risk factors that may help explain the variability in the clinical presentation and severity of CADASIL.
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.
PURPOSE: To report the incidence of symptomatic vertical and torsional diplopia after superior rectus transposition (SRT) for esotropic Duane syndrome and abducens nerve palsy. METHODS: The medical records of patients with esotropic Duane syndrome or abducens nerve palsy seen at Boston Children's Hospital (2006-2018) and treated with unilateral SRT with or without augmentation was performed. The primary outcome was incidence of postoperative vertical or torsional diplopia in primary position. The secondary outcome was induced vertical deviation in affected side gaze. RESULTS: A total of 69 patients met inclusion criteria: 32 with abducens nerve palsy and 37 with esotropic Duane syndrome. Vertical alignment changed in both hyper- and hypotropic directions. Median pre- and postoperative vertical deviation in primary gaze was 1.1 (10th-90th percentile, 0-6 hypertropia) and 0.4 (10th-90th percentile, 6 hypotropia to 8 hypertropia), respectively. Postoperative vertical diplopia occurred in 7%, including 4 of 49 treated with loop myopexy (8%), 1 of 13 without augmentation (8%), and 0 of 7 treated with sclera-fixated augmentation. All but one was successfully treated with prism or secondary surgery. Intorsional change predominated, but no patient had torsional diplopia post adjustment. Vertical misalignment in affected side gaze increased from 19% to 45% after SRT (P = 0.01). CONCLUSIONS: In this largest-to-date review of patients treated with SRT, with or without MR recession, no patient developed persistent torsional diplopia, while 7% developed symptomatic vertical diplopia in primary position, similar to the reported incidence after balanced vertical rectus transposition. Vertical misalignment in affected side gaze increased, however fusion is already limited by unresolved esotropia in this field.
Dockery D, Krzystolik M. The Use of Mobile Applications as Low-Vision Aids: A Pilot Study. R I Med J (2013). 2020;103(8):69–72.
OBJECTIVE: To determine the most commonly used and highest-rated mobile applications (apps) for low-vision aids. METHODS: This was a convenience sample survey. Patients known to use low-vision apps at a nonprofit low-vision center (INSIGHT, Warwick, RI) were contacted by phone between June and September 2019. INCLUSION CRITERIA: age 18+, Snellen visual acuity (VA) below 20/70, and the use of low-vision mobile apps for at least one month. A standardized script was used to record survey data and app ratings were evaluated by patients with a scale of one to five, one being the lowest and five being the highest. RESULTS: Of the sample (n=11), nine patients (81.8%) stated they used an iPhone for low-vision mobile apps. A list of 14 mobile apps was identified: the two most commonly used apps were Seeing AI (81.8%) and Be My Eyes (63.6%); their average ratings were 4.43/5 and 4.75/5, respectively. CONCLUSIONS: This survey suggests that Seeing AI and Be My Eyes are useful apps to help low- vision patients with activities of daily living.
Maidana D, Notomi S, Ueta T, Zhou T, Joseph D, Kosmidou C, Caminal-Mitjana JM, Miller J, Vavvas D. ThicknessTool: automated ImageJ retinal layer thickness and profile in digital images. Sci Rep. 2020;10(1):18459.
To develop an automated retina layer thickness measurement tool for the ImageJ platform, to quantitate nuclear layers following the retina contour. We developed the ThicknessTool (TT), an automated thickness measurement plugin for the ImageJ platform. To calibrate TT, we created a calibration dataset of mock binary skeletonized mask images with increasing thickness masks and different rotations. Following, we created a training dataset and performed an agreement analysis of thickness measurements between TT and two masked manual observers. Finally, we tested the performance of TT measurements in a validation dataset of retinal detachment images. In the calibration dataset, there were no differences in layer thickness between measured and known thickness masks, with an overall coefficient of variation of 0.00%. Training dataset measurements of immunofluorescence retina nuclear layers disclosed no significant differences between TT and any observer's average outer nuclear layer (ONL) (p = 0.998), inner nuclear layer (INL) (p = 0.807), and ONL/INL ratio (p = 0.944) measurements. Agreement analysis showed that bias between TT vs. observers' mean was lower than between any observers' mean against each other in the ONL (0.77 ± 0.34 µm vs 3.25 ± 0.33 µm) and INL (1.59 ± 0.28 µm vs 2.82 ± 0.36 µm). Validation dataset showed that TT can detect significant and true ONL thinning (p = 0.006), more sensitive than manual measurement capabilities (p = 0.069). ThicknessTool can measure retina nuclear layers thickness in a fast, accurate, and precise manner with multi-platform capabilities. In addition, the TT can be customized to user preferences and is freely available to download.
Cakir B, Hellström W, Tomita Y, Fu Z, Liegl R, Winberg A, Hansen-Pupp I, Ley D, Hellström A, Löfqvist C, Smith L. IGF1, serum glucose, and retinopathy of prematurity in extremely preterm infants. JCI Insight. 2020;5(19).
BACKGROUNDHyperglycemia, insulin insensitivity, and low IGF1 levels in extremely preterm infants are associated with an increased risk of retinopathy of prematurity (ROP), but the interactions are incompletely understood.METHODSIn 117 extremely preterm infants, serum glucose levels and parenteral glucose intake were recoded daily in the first postnatal week. Serum IGF1 levels were measured weekly. Mice with oxygen-induced retinopathy alone versus oxygen-induced retinopathy plus streptozotocin-induced hyperglycemia/hypoinsulinemia were assessed for glucose, insulin, IGF1, IGFBP1, and IGFBP3 in blood and liver. Recombinant human IGF1 was injected to assess the effect on glucose and retinopathy.RESULTSThe highest mean plasma glucose tertile of infants positively correlated with parenteral glucose intake [r(39) = 0.67, P < 0.0001]. IGF1 plasma levels were lower in the high tertile compared with those in low and intermediate tertiles at day 28 (P = 0.038 and P = 0.03). In high versus lower glucose tertiles, ROP was more prevalent (34 of 39 versus 19 of 39) and more severe (ROP stage 3 or higher; 71% versus 32%). In oxygen-induced retinopathy, hyperglycemia/hypoinsulinemia decreased liver IGF1 expression (P < 0.0001); rh-IGF1 treatment improved normal vascular regrowth (P = 0.027) and reduced neovascularization (P < 0.0001).CONCLUSIONIn extremely preterm infants, high early postnatal plasma glucose levels and signs of insulin insensitivity were associated with lower IGF1 levels and increased ROP severity. In a hyperglycemia retinopathy mouse model, decreased insulin signaling suppressed liver IGF1 production, lowered serum IGF1 levels, and increased neovascularization. IGF1 supplementation improved retinal revascularization and decreased pathological neovascularization. The data support IGF1 as a potential treatment for prevention of ROP.TRIAL REGISTRATIONClinicalTrials.gov NCT02760472 (Donna Mega).FUNDINGThis study has been supported by the Swedish Medical Research Council (14940, 4732, 20144-01-3, and 21144-01-3), a Swedish government grant (ALFGB2770), Lund medical faculty grants (ALFL, 11615 and 11601), the Skåne Council Foundation for Research and Development, the Linnéa and Josef Carlsson Foundation, the Knut and Alice Wallenberg Foundation, the NIH/National Eye Institute (EY022275, EY017017, EY017017-13S1, and P01 HD18655), European Commission FP7 project 305485 PREVENT-ROP, Deutsche Forschungsgemeinschaft (CA-1940/1-1), and Stiftelsen De Blindas Vänner.
Group WCPEDI, Pineles S, Repka M, Liu G, Waldman A, Borchert M, Khanna S, Heidary G, Graves J, Shah V, Kupersmith M, Kraker R, Wallace D, Cotter S, Holmes J. Assessment of Pediatric Optic Neuritis Visual Acuity Outcomes at 6 Months. JAMA Ophthalmol. 2020;
Importance: Optic neuritis (ON) in children is uncommon. There are limited prospective data for visual acuity (VA) outcomes, associated diseases, and neuroimaging findings. Prospective data from a large sample would be useful for counseling families on treatment decisions and prognosis. Objective: To prospectively study children with a first episode of ON, describe VA after 6 months, and ascertain the network's (Pediatric Eye Disease Investigator Group and Neuro-Ophthalmology Research Disease Investigator Consortium) ability to enroll pediatric patients with ON prospectively. Design, Setting, and Participants: This nonrandomized cohort study was conducted from September 20, 2016, to July 20, 2018, at 23 sites in the United States and Canada in pediatric ophthalmology or neuro-ophthalmology clinics. A total of 44 children (aged 3-15 years) presented with a first episode of ON (visual loss, pain on eye movements, or both) within 2 weeks of symptom onset and at least 1 of the following in the affected eye: a distance high-contrast VA (HCVA) deficit of at least 0.2 logMAR below age-based norms, diminished color vision, abnormal visual field, or optic disc swelling. Exclusion criteria included preexisting ocular abnormalities or a previous episode of ON. Main Outcomes and Measures: Primary outcomes were monocular HCVA and low-contrast VA at 6 months. Secondary outcomes were neuroimaging, associated diagnoses, and antibodies for neuromyelitis optica and myelin oligodendrocyte glycoprotein. Results: A total of 44 children (mean age [SD], 10.2 [3.5] years; 26 boys [59%]; 23 White individuals [52%]; 54 eyes) were enrolled in the study. Sixteen patients (36%) had bilateral ON. Magnetic resonance imaging revealed white matter lesions in 23 children (52%). Of these children, 8 had myelin oligodendrocyte glycoprotein-associated demyelination (18%), 7 had acute disseminated encephalomyelitis (16%), 5 had multiple sclerosis (11%), and 3 had neuromyelitis optica (7%). The baseline mean HCVA was 0.95 logMAR (20/200), which improved by a mean 0.76 logMAR (95% CI, 0.54-0.99; range, -0.70 to 1.80) to 0.12 logMAR (20/25) at 6 months. The baseline mean distance low-contrast VA was 1.49 logMAR (20/640) and improved by a mean 0.72 logMAR (95% CI, 0.54-0.89; range, -0.20 to 1.50) to 0.73 logMAR (20/100) at 6 months. Baseline HCVA was worse in younger participants (aged <10 years) with associated neurologic autoimmune diagnoses, white matter lesions, and in those of non-White race and non-Hispanic ethnicity. The data did not suggest a statistically significant association between baseline factors and improvement in HCVA. Conclusions and Relevance: The study network did not reach its targeted enrollment of 100 pediatric patients with ON over 2 years. This indicates that future treatment trials may need to use different inclusion criteria or plan a longer enrollment period to account for the rarity of the disease. Despite poor VA at presentation, most children had marked improvement by 6 months. Associated neurologic autoimmune diagnoses were common. These findings can be used to counsel families about the disease.