January 2018

Laíns I, Talcott KE, Santos AR, Marques JH, Gil P, Gil J, Figueira J, Husain D, Kim IK, Miller JW, Silva R, Miller JB. CHOROIDAL THICKNESS IN DIABETIC RETINOPATHY ASSESSED WITH SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY. Retina 2018;38(1):173-182.Abstract
PURPOSE: To compare the choroidal thickness (CT) of diabetic eyes (different stages of disease) with controls, using swept-source optical coherence tomography. METHODS: A multicenter, prospective, cross-sectional study of diabetic and nondiabetic subjects using swept-source optical coherence tomography imaging. Choroidal thickness maps, according to the nine Early Treatment Diabetic Retinopathy Study (ETDRS) subfields, were obtained using automated software. Mean CT was calculated as the mean value within the ETDRS grid, and central CT as the mean in the central 1 mm. Diabetic eyes were divided into four groups: no diabetic retinopathy (No DR), nonproliferative DR (NPDR), NPDR with diabetic macular edema (NPDR + DME), and proliferative DR (PDR). Multilevel mixed linear models were performed for analyses. RESULTS: The authors included 50 control and 160 diabetic eyes (n = 27 No DR, n = 51 NPDR, n = 61 NPDR + DME, and n = 21 PDR). Mean CT (ß = -42.9, P = 0.022) and central CT (ß = -50.2, P = 0.013) were statistically significantly thinner in PDR eyes compared with controls, even after adjusting for confounding factors. Controlling for age, DR eyes presented a significantly decreased central CT than diabetic eyes without retinopathy (β = -36.2, P = 0.009). CONCLUSION: Swept-source optical coherence tomography demonstrates a significant reduction of CT in PDR compared with controls. In the foveal region, the choroid appears to be thinner in DR eyes than in diabetic eyes without retinopathy.
M Mallery R, Poolman P, J Thurtell M, Full JM, Ledolter J, Kimbrough D, Frohman EM, Frohman TC, Kardon RH. Visual Fixation Instability in Multiple Sclerosis Measured Using SLO-OCT. Invest Ophthalmol Vis Sci 2018;59(1):196-201.Abstract
Purpose: Precise measurements of visual fixation and its instability were recorded during optical coherence tomography (OCT) as a marker of neural network dysfunction in multiple sclerosis (MS), which could be used to monitor disease progression or response to treatment. Methods: A total of 16 MS patients and 26 normal subjects underwent 30 seconds of scanning laser ophthalmoscope (SLO)-based eye tracking during OCT scanning of retinal layer thickness. Study groups consisted of normal eyes, MS eyes without prior optic neuritis (MS wo ON), and MS eyes with prior optic neuritis (MS + ON). Kernel density estimation quantified fixation instability from the distribution of fixation points on the retina. In MS wo ON eyes, fixation instability was compared to other measures of visual and neurologic function. Results: Fixation instability was increased in MS wo ON eyes (0.062 deg2) compared to normal eyes (0.030 deg2, P = 0.015). A further increase was seen for MS + ON eyes (0.11 deg2) compared to MS wo ON (P = 0.04) and normal (P = 0.006) eyes. Fixation instability correlated weakly with ganglion cell layer (GCL) volume and showed no correlation with low-contrast letter acuity, EDSS score, or SDMT score. Conclusions: Fixation instability reflects the integrity of a widespread neural network germane to visual processing and ocular motor control, and is disturbed in MS. Further study of visual fixation, including the contribution of microsaccades to fixation instability, may provide insight into the localization of fixation abnormalities in MS and introduce innovative and easily measured outcomes for monitoring progression and treatment response.
Ma L, Jakobiec FA, Wolkow N, Dryja TP, Borodic GE. Multiple Eyelid Cysts (Apocrine and Eccrine Hidrocystomas, Trichilemmal Cyst, and Hybrid Cyst) in a Patient With a Prolactinoma. Ophthalmic Plast Reconstr Surg 2018;34(3):e83-e85.Abstract
A 53-year-old man presented with smooth-domed, variegated cysts (polycystic disease) of all 4 eyelids, worse on the left side. Some of the cysts were clear, while others were creamy-white colored. In addition, multiple, very fine vesicopapules were noted along the eyelid margins. Histopathologic examination revealed a trichilemmal cyst, several pure apocrine hidrocystomas displaying multiple chambers, a hybrid cyst, and many small eccrine cysts of the deep dermis. The apocrine lesions, including the small ones at the eyelid margins, predominated. Smooth muscle actin sometimes positively stained outer myoepithelial cells in some of the apocrine cysts, which helped to distinguish them from eccrine cysts. Most noteworthy was the fact that the patient had been diagnosed with a prolactinoma 20 years earlier. There is only 1 previous report of multiple apocrine cysts and an antecedent prolactinoma in the dermatologic literature. This syndrome should be separated from that of Schöpf-Schulz-Passarge, which manifests multiple small eyelid apocrine cysts and other ectodermal dysplasias without any association with neoplasia, and from that of focal dermal hypoplasia (Goltz-Gorlin) syndrome with apocrine cysts but again without neoplasia.
Marsh AP, Edwards TJ, Galea C, Cooper HM, Engle EC, Jamuar SS, Méneret A, Moutard M-L, Nava C, Rastetter A, Robinson G, Rouleau G, Roze E, Spencer-Smith M, Trouillard O, de Villemeur TB, Walsh CA, Yu TW, Yu TW, Heron D, Sherr EH, Richards LJ, Depienne C, Leventer RJ, Lockhart PJ. DCC mutation update: Congenital mirror movements, isolated agenesis of the corpus callosum, and developmental split brain syndrome. Hum Mutat 2018;39(1):23-39.Abstract
The deleted in colorectal cancer (DCC) gene encodes the netrin-1 (NTN1) receptor DCC, a transmembrane protein required for the guidance of commissural axons. Germline DCC mutations disrupt the development of predominantly commissural tracts in the central nervous system (CNS) and cause a spectrum of neurological disorders. Monoallelic, missense, and predicted loss-of-function DCC mutations cause congenital mirror movements, isolated agenesis of the corpus callosum (ACC), or both. Biallelic, predicted loss-of-function DCC mutations cause developmental split brain syndrome (DSBS). Although the underlying molecular mechanisms leading to disease remain poorly understood, they are thought to stem from reduced or perturbed NTN1 signaling. Here, we review the 26 reported DCC mutations associated with abnormal CNS development in humans, including 14 missense and 12 predicted loss-of-function mutations, and discuss their associated clinical characteristics and diagnostic features. We provide an update on the observed genotype-phenotype relationships of congenital mirror movements, isolated ACC and DSBS, and correlate this to our current understanding of the biological function of DCC in the development of the CNS. All mutations and their associated phenotypes were deposited into a locus-specific LOVD (https://databases.lovd.nl/shared/genes/DCC).
Maturi RK, Glassman AR, Liu D, Beck RW, Bhavsar AR, Bressler NM, Jampol LM, Melia M, Punjabi OS, Salehi-Had H, Sun JK, Sun JK. Effect of Adding Dexamethasone to Continued Ranibizumab Treatment in Patients With Persistent Diabetic Macular Edema: A DRCR Network Phase 2 Randomized Clinical Trial. JAMA Ophthalmol 2018;136(1):29-38.Abstract
Importance: Some eyes have persistent diabetic macular edema (DME) following anti-vascular endothelial growth factor (anti-VEGF) therapy for DME. Subsequently adding intravitreous corticosteroids to the treatment regimen might result in better outcomes than continued anti-VEGF therapy alone. Objective: To compare continued intravitreous ranibizumab alone with ranibizumab plus intravitreous dexamethasone implant in eyes with persistent DME. Design, Setting, and Participants: Phase 2 multicenter randomized clinical trial conducted at 40 US sites in 129 eyes from 116 adults with diabetes between February 2014 and December 2016. Eyes had persistent DME, with visual acuity of 20/32 to 20/320 after at least 3 anti-VEGF injections before a run-in phase, which included an additional 3 monthly 0.3-mg ranibizumab injections. Data analysis was according to intent to treat. Interventions: Following the run-in phase, study eyes that had persistent DME and were otherwise eligible were randomly assigned to receive 700 μg of dexamethasone (combination group, 65 eyes) or sham treatment (ranibizumab group, 64 eyes) in addition to continued 0.3-mg ranibizumab in both treatment arms as often as every 4 weeks based on a structured re-treatment protocol. Main Outcomes and Measures: The primary outcome was change in mean visual acuity letter score at 24 weeks as measured by the electronic Early Treatment Diabetic Retinopathy Study (E-ETDRS). The principal secondary outcome was change in mean central subfield thickness as measured with the use of optical coherence tomography. Results: Of the 116 randomized patients, median age was 65 years (interquartile range [IQR], 58-71 years); 50.9% were female and 60.3% were white. Mean (SD) improvement in visual acuity from randomization was 2.7 (9.8) letters in the combination group and 3.0 (7.1) letters in the ranibizumab group, with the adjusted treatment group difference (combination minus ranibizumab) of -0.5 letters (95% CI, -3.6 to 2.5; 2-sided P = .73). Mean (SD) change in central subfield thickness in the combination group was -110 (86) μm compared with -62 (97) μm for the ranibizumab group (adjusted difference, -52; 95% CI, -82 to -22; 2-sided P < .001). Nineteen eyes (29%) in the combination group experienced increased intraocular pressure or initiated treatment with antihypertensive eyedrops compared with 0 in the ranibizumab group (2-sided P < .001). Conclusions and Relevance: Although its use is more likely to reduce retinal thickness and increase intraocular pressure, the addition of intravitreous dexamethasone to continued ranibizumab therapy does not improve visual acuity at 24 weeks more than continued ranibizumab therapy alone among eyes with persistent DME following anti-VEGF therapy. Trial Registration: clinicaltrials.gov Identifier: NCT01945866.
Moein H-R, Kheirkhah A, Muller RT, Cruzat AC, Pavan-Langston D, Hamrah P. Corneal nerve regeneration after herpes simplex keratitis: A longitudinal in vivo confocal microscopy study. Ocul Surf 2018;16(2):218-225.Abstract
PURPOSE: To evaluate the long-term alterations of corneal nerves in patients with herpes simplex virus (HSV) keratitis using in vivo confocal microscopy (IVCM). DESIGN: Prospective, longitudinal, cross sectional. METHODS: This study included 16 patients with a history of HSV keratitis and 15 age-matched normal controls. Slit-scanning IVCM was performed in all subjects at baseline and then after a mean follow-up of 37.3 ± 1.7 months in the patient group. Corneal subbasal nerve density and corneal sensation were compared between groups at baseline and follow-up. RESULTS: At baseline, the mean subbasal nerve density was significantly lower in both affected eyes (1.4 ± 0.6 mm/mm) and contralateral unaffected eyes (6.4 ± 0.7 mm/mm) compared with the controls (14.1 ± 1.6 mm/mm; all P < .001). At the end of follow-up, the mean nerve density in affected eyes increased to 2.8 ± 0.7 mm/mm (P = .006), with no significant change in contralateral unaffected eyes (6.5 ± 1.0 mm/mm, P = .72). However, both eyes had lower nerve density than controls (all P < .001). Corneal sensation was significantly lower in affected eyes (2.6 ± 0.6 cm) than in the control group (6.0 ± 0.0, P < .001) and showed no significant change at the end of follow-up (2.5 ± 0.6 cm, P = .80). Corneal sensation in contralateral unaffected eyes was not different in comparison with controls at both baseline and follow up (all p > .05). CONCLUSIONS: Our results demonstrate that although corneal nerve regeneration occurs in patients with HSV keratitis, this change is not clinically significant and does not results in changes of corneal sensation. Therefore, these patients need to be followed closely for complications of neurotrophic keratopathy and might benefit from neuro-regenerative therapies.
Nascimento H, Viana-Niero C, Nogueira CL, Martins Bispo PJ, Pinto F, de Paula Pereira Uzam C, Matsumoto CK, Oliveira Machado AM, Leão SC, Höfling-Lima AL, de Freitas D. Identification of the Infection Source of an Outbreak of Mycobacterium Chelonae Keratitis After Laser in Situ Keratomileusis. Cornea 2018;37(1):116-122.Abstract
PURPOSE: Nontuberculous mycobacteria keratitis is a rare but challenging complication of laser in situ keratomileusis (LASIK). This study was conducted to determine the source(s) of infection in a cluster of cases of keratitis after LASIK and to describe this outbreak and patients' outcomes. METHODS: In this retrospective, case series, single-center study, 86 patients were included who underwent LASIK or photorefractive keratectomy between December 2011 and February 2012. Corneal scrapes from the affected eyes, samples of tap and distilled water, water from the reservoir of the distilling equipment, steamer, and autoclave cassette; antiseptic and anesthetic solutions and surgical instrument imprints were cultivated in liquid and on solid media. Gram-negative bacteria and yeasts were identified using automated systems and mycobacteria by polymerase chain reaction-restriction enzyme analysis of the hsp65 gene (PRA-hsp65) and DNA sequencing. Mycobacterial isolates were typed by pulsed-field gel electrophoresis. The cases and outcomes are described. The main outcome measure was identification of the source(s) of the mycobacterial infections. RESULTS: Eight (15 eyes) of 86 patients (172 eyes) who underwent LASIK developed infections postoperatively; no patients who underwent photorefractive keratectomy developed infections. Mycobacterium chelonae was isolated from 4 eyes. The distilled water collected in the surgical facility contained the same M. chelonae strain isolated from the patients' eyes. Different gram-negative bacteria and yeasts were isolated from samples collected at the clinic but not from the patients' eyes. CONCLUSIONS: Tap water distilled locally in surgical facilities may be a source of infection after ocular surgery and its use should be avoided.
Rodriguez JD, Lane KJ, Ousler GW, Angjeli E, Smith LM, Abelson MB. Blink: Characteristics, Controls, and Relation to Dry Eyes. Curr Eye Res 2018;43(1):52-66.Abstract
Blink is a complex phenomenon that is profoundly affected by diverse endogenous and exogenous stimuli. It has been studied in the context of cognition, emotional, and psychological states, as an indicator of fatigue and sleepiness, particularly in the automobile and transportation industry, in visual tasking, and finally, as it relates to tear film stability and ocular surface health. The fact that it is highly variable and has input from so many sources makes it very difficult to study. In the present review, the behavior of blink in many of these systems is discussed, ultimately returning in each instance to a discussion of how these factors affect blink in the context of dry eyes. Blink is important to ocular surface health and to an individual's optimal functioning and quality of life. Disturbances in blink, as cause or effect, result in a breakdown of tear film stability, optical clarity, and visual function.
Salongcay RP, Silva PS. The Role of Teleophthalmology in the Management of Diabetic Retinopathy. Asia Pac J Ophthalmol (Phila) 2018;Abstract
The emergence of diabetes as a global epidemic is accompanied by the rise in diabetes‑related retinal complications. Diabetic retinopathy, if left undetected and untreated, can lead to severe visual impairment and affect an individual's productivity and quality of life. Globally, diabetic retinopathy remains one of the leading causes of visual loss in the working‑age population. Teleophthalmology for diabetic retinopathy is an innovative means of retinal evaluation that allows identification of eyes at risk for visual loss, thereby preserving vision and decreasing the overall burden to the health care system. Numerous studies worldwide have found teleophthalmology to be a reliable and cost‑efficient alternative to traditional clinical examinations. It has reduced barriers to access to specialized eye care in both rural and urban communities. In teleophthalmology applications for diabetic retinopathy, it is critical that standardized protocols in image acquisition and evaluation are used to ensure low image ungradable rates and maintain the quality of images taken. Innovative imaging technology such as ultrawide field imaging has the potential to provide significant benefit with integration into teleophthalmology programs. Teleophthalmology programs for diabetic retinopathy rely on a comprehensive and multidisciplinary approach with partnerships across specialties and health care professionals to attain wider acceptability and allow evidence‑based eye care to reach a much broader population.
Sun D. Visualizing Astrocytes of the Optic Nerve. Methods Mol Biol 2018;1695:269-286.Abstract
Astrocytes make up approximately 30% of all the cells in the mammalian central nervous system. They are not passive, as once thought, but are integral to brain physiology and perform many functions that are important for normal neuronal development and metabolism, synapse formation, synaptic transmission, and in repair following injury/disease. Astrocytes also communicate with neurons, blood vessels, and other types of glial cells. Astrocytes within the optic nerve head region play a key role in glaucomatous axon degeneration. In this chapter, we describe ways in which astrocytes of the optic nerve head can be visualized, beginning with basic immunohistochemical staining methods, to single-cell dye injections and then to transgenic animals. We will also discuss the pros and cons of each method. Many of the methods were initially developed to visualize brain astrocytes; in some cases, the method has translated well to astrocytes of the optic nerve, and in others, it remains unclear.
Tao Y, Huang M, Shu Y, Ruprecht A, Wang H, Tang Y, Vandenberghe LH, Wang Q, Gao G, Kong W-J, Chen Z-Y. Delivery of Adeno-Associated Virus Vectors in Adult Mammalian Inner-Ear Cell Subtypes Without Auditory Dysfunction. Hum Gene Ther 2018;29(4):492-506.Abstract
Hearing loss, including genetic hearing loss, is one of the most common forms of sensory deficits in humans with limited options of treatment. Adeno-associated virus (AAV)-mediated gene transfer has been shown to recover auditory functions effectively in mouse models of genetic deafness when delivered at neonatal stages. However, the mouse cochlea is still developing at those time points, whereas in humans, the newborn inner ears are already fully mature. For effective gene therapy to treat genetic deafness, it is necessary to determine whether AAV-mediated therapy can be equally effective in the fully mature mouse inner ear without causing damage to the inner ear. This study tested several AAV serotypes by canalostomy in adult mice. It is shown that most AAVs transduce the sensory inner hair cells efficiently, but are less efficient at transducing outer hair cells. A subset of AAVs also transduces non-sensory cochlear cell types. Neither the surgical procedure of canalostomy nor the AAV serotypes damage hair cells or impair normal hearing. The studies indicate that canalostomy can be a viable route for safe and efficient gene delivery, and they expand the repertoire of AAVs to target diverse cell types in the adult inner ear.
Vavvas DG, Small KW, Awh CC, Zanke BW, Tibshirani RJ, Kustra R. CFH and ARMS2 genetic risk determines progression to neovascular age-related macular degeneration after antioxidant and zinc supplementation. Proc Natl Acad Sci U S A 2018;Abstract
We evaluated the influence of an antioxidant and zinc nutritional supplement [the Age-Related Eye Disease Study (AREDS) formulation] on delaying or preventing progression to neovascular AMD (NV) in persons with age-related macular degeneration (AMD). AREDS subjects (n = 802) with category 3 or 4 AMD at baseline who had been treated with placebo or the AREDS formulation were evaluated for differences in the risk of progression to NV as a function of complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2) genotype groups. We used published genetic grouping: a two-SNP haplotype risk-calling algorithm to assess CFH, and either the single SNP rs10490924 or 372_815del443ins54 to mark ARMS2 risk. Progression risk was determined using the Cox proportional hazard model. Genetics-treatment interaction on NV risk was assessed using a multiiterative bootstrap validation analysis. We identified strong interaction of genetics with AREDS formulation treatment on the development of NV. Individuals with high CFH and no ARMS2 risk alleles and taking the AREDS formulation had increased progression to NV compared with placebo. Those with low CFH risk and high ARMS2 risk had decreased progression risk. Analysis of CFH and ARMS2 genotype groups from a validation dataset reinforces this conclusion. Bootstrapping analysis confirms the presence of a genetics-treatment interaction and suggests that individual treatment response to the AREDS formulation is largely determined by genetics. The AREDS formulation modifies the risk of progression to NV based on individual genetics. Its use should be based on patient-specific genotype.
Vazirani J, Nair D, Shanbhag S, Wurity S, Ranjan A, Sangwan V. Limbal Stem Cell Deficiency - Demography And Underlying Causes. Am J Ophthalmol 2018;Abstract
PURPOSE: To determine the demographic features of patients affected by limbal stem cell deficiency (LSCD), and to identify the underlying causes of LSCD DESIGN: Retrospective, multi-center case series SETTING: Two large tertiary care ophthalmology hospitals SUBJECTS: Patients with a diagnosis of LSCD presenting from January 1, 2005 to December 31, 2014 METHODS: Records of patients with a clinical diagnosis of LSCD were reviewed. Demographic details and clinical features at presentation, as well as the underlying cause of LSCD (if identified) were noted. Descriptive statistical analysis and chart preparation were done. MAIN OUTCOME MEASURES: Type of LSCD (unilateral or bilateral), age and sex of patients, extent of LSCD (clock hours of limbus involved) and underlying cause of LSCD RESULTS: We found 1331 patients with LSCD in the ten year period under study. Unilateral LSCD was more common (791 patients) than bilateral LSCD (540 patients). Out of 1331 patients, 875 (65.74%) were male. The median age of patients was 24 years. Extent of LSCD could be determined in 1849 eyes, of which 1239 eyes (67%) had total LSCD. The underlying cause of LSCD could be identified in 1512 eyes. In cases of unilateral LSCD, ocular surface burns was the commonest identifiable cause ( 83.73%). The leading identifiable causes of bilateral LSCD were ocular surface burns (29.95%), allergic conjunctivitis (29.48%), Stevens Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) (23.11%), aniridia (9.43%) and mucous membrane pemphigoid (3.54%). Lime ("chuna") injury was responsible for ocular surface burns in 352 (62.08%) out of 567 cases in which the agent was identified. CONCLUSIONS: In our study, unilateral LSCD was more common than bilateral LSCD. Young males were commonly affected, with a majority of eyes suffering from total LSCD. Overall, ocular surface burns are the leading cause of LSCD.Unilateral and bilateral LSCD had a markedly different distribution of causes, necessitating different approaches to management.
Wolkow N, Jakobiec FA, Hatton MP. A Common Procedure With an Uncommon Pathology: Triamcinolone Acetonide Eyelid Injection. Ophthalmic Plast Reconstr Surg 2018;34(3):e72-e73.Abstract
Local corticosteroid injections are frequently employed by ophthalmologists to treat a variety of ocular, periocular, and orbital inflammatory conditions. Triamcinolone acetonide is a slowly dissolving crystalline corticosteroid that is often used for this purpose because of its prolonged anti-inflammatory effect. On occasion, previously injected corticosteroid material persists in tissues longer than anticipated, creating nodules that may masquerade as other disease conditions, or appearing incidentally in excised lesions on histopathologic examination. The histopathologic features of corticosteroid residues are unfamiliar to most ophthalmic pathologists and general pathologists. These features are described herein. Triamcinolone acetonide deposits in the skin appear as pale eosinophilic lakes of acellular frothy material on hematoxylin-eosin staining and are occasionally surrounded by a mild inflammatory reaction.
Yin Y, Benowitz LI. In Vitro and In Vivo Methods for Studying Retinal Ganglion Cell Survival and Optic Nerve Regeneration. Methods Mol Biol 2018;1695:187-205.Abstract
Glaucoma is marked by a progressive degeneration of the optic nerve and delayed loss of retinal ganglion cells (RGCs), the projection neurons of the eye. Because RGCs are not replaced and because surviving RGCs cannot regenerate their axons, the visual loss in glaucoma is largely irreversible. Here, we describe methods to evaluate treatments that may be beneficial for treating glaucoma using in vitro cell culture models (immunopanning to isolate neonatal RGCs, dissociated mature retinal neurons, retinal explants) and in vivo models that test potential treatments or investigate underlying molecular mechanisms in an intact system. Potentially, use of these models can help investigators continue to improve treatments to preserve RGCs and restore visual function in patients with glaucoma.