Multivariate Models to Diagnose Early Referral-Warranted Retinopathy of Prematurity With Handheld Optical Coherence Tomography.

Purpose: The purpose of this study was to create multivariate models predicting early referral-warranted retinopathy of prematurity (ROP) using non-contact handheld spectral-domain optical coherence tomography (OCT) and demographic data. Methods: Between July 2015 and February 2018, infants ≤1500 grams birth weight or ≤30 weeks gestational age from 2 academic neonatal intensive care units were eligible for this study. Infants were excluded if they were too unstable to participate in ophthalmologic examination (2), had inadequate image quality (20), or received prior ROP treatment (2). Multivariate models were created using demographic variables and imaging findings to identify early referral-warranted ROP (referral-warranted ROP and/or pre-plus disease) by routine indirect ophthalmoscopy. Results: A total of 167 imaging sessions of 71 infants (45% male infants, gestational age 28.2+/-2.8 weeks, and birth weight 995.6+/-292.0 grams) were included. Twelve of 71 infants (17%) developed early referral-warranted ROP. The area under the receiver operating characteristic curve (AUC) was 0.94 for the generalized linear mixed model (sensitivity = 95.5% and specificity = 80.7%) and 0.83 for the machine learning model (sensitivity = 91.7% and specificity = 77.8%). The strongest variables in both models were birth weight, image-based Vitreous Opacity Ratio (an estimate of opacity density), vessel elevation, and hyporeflective vessels. A model using only birth weight and gestational age yielded an AUC of 0.68 (sensitivity = 77.3% and specificity = 63.4%), and a model using only imaging biomarkers yielded 0.88 (sensitivity = 81.8% and specificity = 84.8%). Conclusions: A generalized linear mixed model containing handheld OCT biomarkers can identify early referral-warranted ROP. Machine learning produced a less optimal model. Translational Relevance: With further validation, this work may lead to a better-tolerated ROP screening tool.

Dome-shaped macula in premature infants visualized by handheld spectral-domain optical coherence tomography.

PURPOSE: To describe dome-shaped macula and associated clinical findings in premature infants. METHODS: This prospective, observational cohort study included a consecutive sample of premature infants screened for retinopathy of prematurity (ROP) with 9-month follow-up. Handheld spectral domain optical coherence tomography (SD-OCT) was performed at the time of ROP screening. Images were assessed for dome-shaped macula, cystoid macular edema, epiretinal membrane, vitreous bands, and punctate hyperreflective vitreous opacities. Dome height measurements were performed in a subset of images. Teller visual acuity and cycloplegic refraction were performed at an adjusted age of 8-10 months. RESULTS: Of 37 infants (74 eyes; 49% male; mean gestational age 27.8 ± 3.2 weeks; mean birth weight 949 ± 284 g), 24/37 (65%) demonstrated dome-shaped macula in at least one eye (13 both eyes, 5 right eye only, and 6 left eye only). Of the 74 eyes, 26 (35%) could be reliably measured, with a mean dome height of 139.0 ± 72.3 µm (range, 54-369 µm). Presence of dome-shaped macula was associated with a diagnosis of ROP (P = 0.02; OR, 3.03; 95% CI, 1.18-7.82) and pre-plus or plus disease (P = 0.02; OR, 4.20; 95% CI, 1.05-16.78). Infants with dome-shaped macula had lower birth weight compared with those without (877 vs 1081 g; P = 0.04). No associations with other demographics, OCT findings, and 9-month refractive outcomes were found. CONCLUSIONS: Dome-shaped macula was frequently identified by handheld SD-OCT in premature infants, especially those with lower birth weight and severe ROP. The long-term clinical significance of this finding is unknown.

Vitreous Findings by Handheld Spectral-Domain OCT Correlate with Retinopathy of Prematurity Severity.

PURPOSE: To evaluate the association between retinopathy of prematurity (ROP) and vitreous findings in premature infants detected by handheld spectral-domain (SD) OCT. DESIGN: Prospective, observational cohort study. PARTICIPANTS: Consecutive sample of 92 premature infants requiring ROP screening at 2 academic neonatal intensive care units between July 2015 and March 2018. METHODS: Infants underwent handheld SD OCT at the time of routine ROP examinations. Two masked, trained graders analyzed right-eye vitreoretinal findings, including semiautomated quantification of punctate hyperreflective vitreous opacities within 5 foveal or parafoveal B-scans (vitreous opacity ratio). MAIN OUTCOME MEASURES: Excluding posttreatment data, vitreous findings were compared with clinical ROP diagnoses. RESULTS: Agreement between image graders for all vitreoretinal findings was 91% (κ = 0.86; 95% confidence interval, 0.82-0.90; P < 0.001). Among 92 infants undergoing 280 imaging sessions (52% male; mean gestational age, 28.3 ± 2.8 weeks; mean birthweight, 1014.5 ± 285.0 g), 36 of 92 (39%) demonstrated ROP. Punctate hyperreflective vitreous opacities were identified in 61 of 92 infants (66%). The presence of punctate hyperreflective vitreous opacities at least once was associated with a diagnosis of ROP (62% vs. 29% without opacities; P = 0.003), maximum ROP stage (P = 0.001), preplus or plus disease (24% vs. 5%; P = 0.005), and type 1 disease (14% vs. 2%; P = 0.03). Among 29 infants (45 imaging sessions) with right-eye punctate hyperreflective vitreous opacities, the vitreous opacity ratio from 2 graders (F1 score, 0.82 ± 0.36; Dice coefficient, 0.97 ± 0.04) correlated with ROP stage (P = 0.02). Tractional vitreous bands on imaging correlated with plus disease status (29% vs. 5% without bands; P = 0.05). CONCLUSIONS: Punctate hyperreflective vitreous opacities and tractional vitreous bands predict the presence and severity of ROP. Further studies should explore handheld OCT as a noninvasive ROP screening tool.

Trophic cascades induced by lobster fishing are not ubiquitous in southern California kelp forests.

Fishing can trigger trophic cascades that alter community structure and dynamics and thus modify ecosystem attributes. We combined ecological data of sea urchin and macroalgal abundance with fishery data of spiny lobster (Panulirus interruptus) landings to evaluate whether: (1) patterns in the abundance and biomass among lobster (predator), sea urchins (grazer), and macroalgae (primary producer) in giant kelp forest communities indicated the presence of top-down control on urchins and macroalgae, and (2) lobster fishing triggers a trophic cascade leading to increased sea urchin densities and decreased macroalgal biomass. Eight years of data from eight rocky subtidal reefs known to support giant kelp forests near Santa Barbara, CA, USA, were analyzed in three-tiered least-squares regression models to evaluate the relationships between: (1) lobster abundance and sea urchin density, and (2) sea urchin density and macroalgal biomass. The models included reef physical structure and water depth. Results revealed a trend towards decreasing urchin density with increasing lobster abundance but little evidence that urchins control the biomass of macroalgae. Urchin density was highly correlated with habitat structure, although not water depth. To evaluate whether fishing triggered a trophic cascade we pooled data across all treatments to examine the extent to which sea urchin density and macroalgal biomass were related to the intensity of lobster fishing (as indicated by the density of traps pulled). We found that, with one exception, sea urchins remained more abundant at heavily fished sites, supporting the idea that fishing for lobsters releases top-down control on urchin grazers. Macroalgal biomass, however, was positively correlated with lobster fishing intensity, which contradicts the trophic cascade model. Collectively, our results suggest that factors other than urchin grazing play a major role in controlling macroalgal biomass in southern California kelp forests, and that lobster fishing does not always catalyze a top-down trophic cascade.