Purpose: Localization of the lacrimal sac is a critical step during endoscopic dacryocystorhinostomy (endo-DCR). A "light pipe" can be used to transilluminate the lacrimal sac endonasally. We hypothesized that this may misguide the surgeon learning endo-DCR to create an osteotomy mostly posterior to the maxillary line if only the bone overlying the transillumination was to be removed, as the thinner lacrimal bone will transmit light more readily than the thicker maxillary bone of the frontal process of the maxilla that forms the anterior lacrimal sac fossa.Methods: The charts of 32 patients with primary acquired nasolacrimal duct obstruction in whom a lighted system was used during endo-DCR at Massachusetts Eye and Ear from April 2015 through October 2016 were reviewed. Patients with prior history of lacrimal surgery or trauma directly to the lacrimal sac fossa were excluded. Location of the maximal point of transillumination in relation to the maxillary line was observed and noted intraoperatively.Results: Of a total of 39 endo-DCR surgeries performed, the intraoperative transillumination point was entirely posterior to the maxillary line in 32 instances (82%).Conclusions: Use of an endocanalicular light pipe preferentially illuminates posterior to the maxillary line endonasally. The anterior lacrimal sac fossa (maxillary line and anterior as visualized endonasally) is rarely transilluminated, likely due to thicker bone in that region. Surgeons learning how to perform endo-DCR using a light pipe should be aware of this phenomenon.
PURPOSE: We previously reported that archetypal analysis (AA), a type of unsupervised machine learning, identified and quantified patterns of visual field (VF) loss in idiopathic intracranial hypertension (IIH), referred to as archetypes (ATs). We assessed whether AT weight changes over time are consistent with changes in conventional global indices. We explored whether visual outcome or treatment effects are associated with select ATs and whether AA reveals residual VF defects in eyes deemed "normal" after treatment. DESIGN: Analysis of data collected from a randomized controlled trial. PARTICIPANTS: 2,862 VFs taken from 165 participants during the Idiopathic Intracranial Hypertension Treatment Trial (IIHTT). METHODS: We applied a 14-AT model derived from IIHTT VFs. We examined changes in individual AT weights over time within all study eye VFs and evaluated differences between treatment groups. We created an AT Change score to assess overall VF change from baseline. We tested threshold baseline AT weights for association with VF outcome and treatment effect at six months. We determined the abnormal ATs with meaningful weight at outcome for VFs considered "normal" based on a mean deviation (MD) cutoff ≥-2.00 dB. MAIN OUTCOME MEASURES: Individual AT weighting coefficients, MD. RESULTS: AT1 (a normal VF pattern) showed the greatest weight change for all study eyes, increasing from 11.9% (interquartile range [IQR]: 0.44-24.1%) at baseline to 31.2% (IQR: 16.0-45.5%) at outcome (p<0.001). AT1 weight change (r=0.795, p<0.001) and a global score of AT change (r=0.988, p<0.001) correlated strongly with MD change. Study eyes with baseline AT2 (a mild diffuse VF loss pattern) weight ≥ 44% (≥1 standard deviation above the mean) showed higher AT2 weights at outcome than those with AT2 < 44% at baseline (p<0.001). Only the latter group showed a significant acetazolamide treatment effect. AA revealed residual VF loss patterns, most frequently representing mild diffuse loss and enlarged blind spot in 64 of 66 study eyes with MD ≥-2.00 dB at outcome. CONCLUSION: AA provides a quantitative approach to monitoring VF changes in IIH. Baseline AT features may be associated with treatment response and VF outcome. AA uncovers residual VF defects not otherwise revealed by MD.
PURPOSE: To determine the association of the multifocal electroretinographic (mfERG) response amplitude with the volumes of the inner, postreceptor, and photoreceptor retinal layers in the region stimulated by each mfERG element. METHODS: Sixteen healthy, young adult control subjects were studied. Each of the 103 hexagonal elements of the standard, scaled mfERG were aligned, where possible, with patches of retina imaged using optical coherence tomography. Stimuli falling on the fovea and on the optic nerve head were excluded. Linear mixed-effects modeling was then used to derive estimated coefficients (voltage/volume) for the mfERG response throughout the full 80 ms standard epoch. The resulting predicted response amplitudes originating in each layer were then compared to pharmacologically "dissected" mfERGs obtained from other studies in monkey eyes. RESULTS: Across the duration of the response, the amplitude of the modeled contribution from (1) the inner retina was small-to-modest, (2) the postreceptor retina was larger and contained two prominent peaks, and (3) the photoreceptor response was the largest and most closely paralleled the overall (i.e., intact) response, including late-appearing oscillations. The significance of each layer's contribution was greatest when the absolute amplitude of that layer's response was largest. The contribution of the inner retina was maximally significant in the interval between the prominent troughs and peaks of the intact response. The contributions of the postreceptor and photoreceptor responses were maximally significant at the prominent troughs and peaks of the intact response. CONCLUSIONS: The results of the model were in good overall agreement with previous interpretations of the cellular contributions to the mfERG. There was also fair agreement with pharmacologically dissected monkey mfERG responses. Thus, the estimations of the contributions of the retinal layers to the mfERG so produced appeared plausible.
This study defines retinal phosphatic metabolites and their adjustment to illumination in rat retinas under conditions that preserve retinal function. Metabolic data are measured using high-performance liquid chromatography (HPLC) and 31P nuclear magnetic resonance (31P NMR) spectroscopy after 10 min of light exposure in vivo compared with retinas from dark-adapted rats. Multiple high-energy and low-energy phosphatic metabolites of intermediary metabolism were quantified. The concentration of the high-energy phosphate adenosine triphosphate (ATP) remained unchanged from dark- to light-adaptation. Under the same conditions the concentrations of the high-energy phosphates guanosine triphosphate (GTP) and creatine phosphate increased, whereas the inorganic phosphate decreased. Comparing dark-adapted controls with retinas light-adapted either in vitro or in vivo, the evidence is consistent with a light-dependent increase in GTP and a decrease in cyclic guanosine monophosphate. Although cyclic adenosine monophosphate (cAMP) levels were lower in retinas light-adapted in vivo than in the dark-adapted controls, this did not seem to be an effect of light, as cAMP levels decreased similarly after 10 min incubation in dark or light in parallel with recovery of ATP/adenosine diphosphate ratios. This study: (1) reports on retinal metabolic changes with adjustment in illumination, (2) provides baseline measurements of retinal phosphatic metabolites in whole retinas, and (3) reports on the validity of chromatographic and spectroscopic methods used for studying retinal metabolism establishing a high correlation among measurements made using HPLC and 31P NMR.
PURPOSE: To report refractive error findings in Baltimore City schoolchildren who failed school-based vision screenings. METHODS: In this cross-sectional analysis, students pre-kindergarten through 8th grade who failed screenings during school years 2016-2019 received an eye examination, including non-cycloplegic autorefraction and visual acuity (VA) measurements. Refractive error was identified when there was at least: -0.50 diopter (D) spherical equivalent (SE) myopia, +0.50D SE hyperopia, 1.00D astigmatism, or 1.00D anisometropia in either eye. Generalized estimating equation models were used to identify factors associated with clinically significant refractive error, defined as decreased VA and more severe refractive error. RESULTS: Of 7520 students who failed screening, 6627 (88%) were analyzed. Clinically significant refractive error and any refractive error were found in 2352 (35.5%) and 5952 (89.8%) students, respectively. Mild myopia (45%, -0.50 D to <-3.00 D SE) and low astigmatism (47%, 1.00 D to <3.00 D cylinder) were the most prevalent types of refractive error. Proportions of students with myopia increased with higher grade levels (Ptrend<0.001). Myopia and astigmatism were more common in black and Latinx. Risk factors for clinically significant refractive error included higher grades (odds ratios [OR] ranged from 1.30 to 2.19 compared with 1st grade, P < .05) and Latinx ethnicity (OR = 1.31, 95%CI: 1.08-1.59). CONCLUSION: A Baltimore school-based vision program identified a substantial number of students with refractive error in a high-poverty urban community. Over 1/3 students who failed vision screening had clinically significant refractive error, with black and Latinx students at higher risk of having myopia and astigmatism.
Halawa OA, Kolli A, Oh G, Mitchell WG, Glynn RJ, Kim DH, Friedman DS, Zebardast N. Reply. Ophthalmology 2022;
PURPOSE: To elucidate risk factors for revision or removal of glaucoma drainage devices (GDD) in glaucoma patients in the United States. DESIGN: Retrospective cohort study. METHODS: IRIS® Registry (Intelligent Research in Sight) patients who underwent GDD insertion between 01/01/2013 and 12/31/2018 were included. Various demographic and clinical factors were collected. Kaplan-Meier (KM) survival plots, Cox proportional-hazard models utilizing Firth's Penalized Likelihood (CRFPL), and multivariate linear regression models were used. The main outcome measures were hazard ratios (HRs) and beta coefficient (β) estimates. RESULTS: 44,330 distinct patients underwent at least one GDD implantation, and 3,354 of these underwent subsequent GDD revision or removal surgery. With failure defined as GDD revision/removal, factors significantly associated with decreased failure included unknown race (HR=0.83; p=0.004) and unknown ethnicity (HR=0.68; p<0.001). Factors associated with increased risk of GDD revision/removal surgery included presence of chronic angle closure glaucoma (HR=1.32; p<0.001) and dry eye disease (HR=1.30; p=0.007). Additionally, factors associated with a decreased average time (in days) to GDD revision/removal included male sex (β=-25.96; p=0.044), unknown race (β=-55.28; p=0.013), and right-eye laterality (β=-38.67; p=0.026). Factors associated with an increased average time to GDD revision/removal included having a history of a past eye procedure (β=104.83; p<0.001) and being an active smoker (β=38.15; p=0.024). CONCLUSIONS: The size and scope of the IRIS Registry allows for detection of subtle associations between risk factors and GDD revision or removal surgery. Aforementioned demographic and clinical factors may all have an impact on GDD longevity and can inform the treatment options available for glaucoma patients.