Huang L, Sun X, Luo G, Liu S, Liu R, Mansouri B, Wong VWL, Wen W, Liu H, Wang A-H. Interocular Shift of Visual Attention Enhances Stereopsis and Visual Acuities of Anisometropic Amblyopes beyond the Critical Period of Visual Development: A Novel Approach. J Ophthalmol 2014;2014:615213.Abstract
Aims. Increasing evidence shows that imbalanced suppressive drive prior to binocular combination may be the key factor in amblyopia. We described a novel binocular approach, interocular shift of visual attention (ISVA), for treatment of amblyopia in adult patients. Methods. Visual stimuli were presented anaglyphically on a computer screen. A square target resembling Landolt C had 2 openings, one in red and one in cyan color. Through blue-red goggles, each eye could only see one of the two openings. The patient was required to report the location of the opening presented to the amblyopic eye. It started at an opening size of 800 sec of arc, went up and down in 160 sec of arc step, and stopped when reaching the 5th reversals. Ten patients with anisometropic amblyopia older than age 14 (average age: 26.7) were recruited and received ISVA treatment for 6 weeks, with 2 training sessions per day. Results. Both Titmus stereopsis (z = -2.809, P = 0.005) and Random-dot stereopsis (z = -2.317, P = 0.018) were significantly improved. Average improvement in best corrected visual acuity (BCVA) was 0.74 line (t = 5.842, P < 0.001). Conclusions. The ISVA treatment may be effective in treating amblyopia and restoring stereoscopic function.
Harrison WJ, Bex PJ. Integrating retinotopic features in spatiotopic coordinates. J Neurosci 2014;34(21):7351-60.Abstract
The receptive fields of early visual neurons are anchored in retinotopic coordinates (Hubel and Wiesel, 1962). Eye movements shift these receptive fields and therefore require that different populations of neurons encode an object's constituent features across saccades. Whether feature groupings are preserved across successive fixations or processing starts anew with each fixation has been hotly debated (Melcher and Morrone, 2003; Melcher, 2005, 2010; Knapen et al., 2009; Cavanagh et al., 2010a,b; Morris et al., 2010). Here we show that feature integration initially occurs within retinotopic coordinates, but is then conserved within a spatiotopic coordinate frame independent of where the features fall on the retinas. With human observers, we first found that the relative timing of visual features plays a critical role in determining the spatial area over which features are grouped. We exploited this temporal dependence of feature integration to show that features co-occurring within 45 ms remain grouped across eye movements. Our results thus challenge purely feedforward models of feature integration (Pelli, 2008; Freeman and Simoncelli, 2011) that begin de novo after every eye movement, and implicate the involvement of brain areas beyond early visual cortex. The strong temporal dependence we quantify and its link with trans-saccadic object perception instead suggest that feature integration depends, at least in part, on feedback from higher brain areas (Mumford, 1992; Rao and Ballard, 1999; Di Lollo et al., 2000; Moore and Armstrong, 2003; Stanford et al., 2010).
Gonzalez-Saldivar G, Lee GN, Chodosh J, Freitag SK, Stacy RC. Dacryops in the setting of a Boston type II keratoprosthesis. Ophthalmic Plast Reconstr Surg 2014;30(3):e73-5.Abstract
Dacryops of the lacrimal tissue can develop under diverse circumstances. Recent evidence suggests that scarring or obstruction of the lacrimal ducts may lead to their dilatation and formation of a cystic structure. Patients who undergo repeated orbital surgery may therefore be at greater risk of dacryops formation. In this report, a patient who underwent multiple corneal and glaucoma procedures including Boston type II keratoprosthesis, after acid burns to both eyes, is described. Over time, a fluid-filled collection developed in the lower orbit. On surgical exploration and incision, fluid was drained from a cystic lesion which abutted the lacrimal gland and spanned the upper and lower orbits. The lesion was removed and was proven by histopathology and immunohistochemistry to be dacryops. This is the first known case of dacryops associated with Boston type II keratoprosthesis.
Engel MJ, Guyton DL, Hunter DG. Adjustable sutures in children. J AAPOS 2014;18(3):278-84.Abstract
Although adjustable sutures are considered a standard technique in adult strabismus surgery, most surgeons are hesitant to attempt the technique in children, who are believed to be unlikely to cooperate for postoperative assessment and adjustment. Interest in using adjustable sutures in pediatric patients has increased with the development of surgical techniques specific to infants and children. This workshop briefly reviews the literature supporting the use of adjustable sutures in children and presents the approaches currently used by three experienced strabismus surgeons.
Khurelbat D, Dorj G, Bayarsaikhan E, Chimedsuren M, Sanjjav T, Morimoto T, Morley M, Morley K. Prevalence estimates of substandard drugs in Mongolia using a random sample survey. Springerplus 2014;3:709.Abstract
To determine the prevalence of substandard drugs in urban (Ulaanbaatar) and rural (selected provinces) areas of Mongolia, samples of 9 common, therapeutically important drugs were collected from randomly selected drug outlets in Ulaanbaatar and 4 rural provinces by "mystery shoppers". Samples were analyzed by visual inspection, registration status, and biochemical analysis. Samples failing to meet all Pharmacopeia quality tests were considered substandard. In the rural provinces, 69 out of 388 samples were substandard, giving an estimated prevalence of substandard drugs of 17.8% (95% CI: 14.1-22.0). There were 85 unregistered samples, giving a prevalence estimate of unregistered drugs of 21.9%. (95% CI: 17.9-26.3). In the urban Ulaanbaatar districts, 112 out of 848 samples were substandard, giving an estimated prevalence of substandard drugs of 13.2% (95% CI: 11.0-15.7). There were 150 unregistered samples, giving a prevalence estimate of unregistered drugs of 17.7% (95% CI: 15.2-20.4). In the rural provinces, 35 out of 85 (41.2%) unregistered samples were substandard; whereas 34 out of 303 (11.2%) registered samples were substandard. (p < 0.0001) In the urban districts, 18 out of 150 (12.0%) unregistered samples were substandard, whereas 94 out of 698 registered were substandard. (13.5%) (p = 0.6). The prevalence of substandard and unregistered drugs is higher in rural provinces. There is a significant association between substandard and unregistered drugs in the provinces but not in the urban districts. The underlying causes for substandard drugs need to be further investigated in order to help formulate strategies to improve pharmacovigilance and the drug supply quality in Mongolia.
Jung J-H, Peli E. Impact of high power and angle of incidence on prism corrections for visual field loss. Opt Eng 2014;53(6)Abstract
Prism distortions and spurious reflections are not usually considered when prescribing prisms to compensate for visual field loss due to homonymous hemianopia. Distortions and reflections in the high power Fresnel prisms used in peripheral prism placement can be considerable, and the simplifying assumption that prism deflection power is independent of angle of incidence into the prisms results in substantial errors. We analyze the effects of high prism power and incidence angle on the field expansion, size of the apical scotomas, and image compression/expansion. We analyze and illustrate the effects of reflections within the Fresnel prisms, primarily due to reflections at the bases, and secondarily due to surface reflections. The strength and location of these effects differs materially depending on whether the serrated prismatic surface is placed toward or away from the eye, and this affects the contribution of the reflections to visual confusion, diplopia, false alarms, and loss of contrast. We conclude with suggestions for controlling and mitigating these effects in clinical practice.
Hwang AD, Peli E. Instability of the perceived world while watching 3D stereoscopic imagery: A likely source of motion sickness symptoms. Iperception 2014;5(6):515-35.Abstract
Watching 3D content using a stereoscopic display may cause various discomforting symptoms, including eye strain, blurred vision, double vision, and motion sickness. Numerous studies have reported motion-sickness-like symptoms during stereoscopic viewing, but no causal linkage between specific aspects of the presentation and the induced discomfort has been explicitly proposed. Here, we describe several causes, in which stereoscopic capture, display, and viewing differ from natural viewing resulting in static and, importantly, dynamic distortions that conflict with the expected stability and rigidity of the real world. This analysis provides a basis for suggested changes to display systems that may alleviate the symptoms, and suggestions for future studies to determine the relative contribution of the various effects to the unpleasant symptoms.
Hong J, Liu Z, Hua J, Wei A, Xue F, Yang Y, Sun X, Xu J. Evaluation of age-related changes in noninvasive tear breakup time. Optom Vis Sci 2014;91(2):150-5.Abstract
PURPOSE: To establish normal noninvasive tear film breakup time (NI-BUT) values in the Chinese population and investigate age-related changes in NI-BUT using a newly developed Keratograph. METHODS: Forty normal volunteers with a mean age of 32.8 ± 16.7 years were recruited for this study. Clinical and demographic data, including age, gender, fluorescein tear film breakup time (FBUT), and Schirmer I test values were collected from the subjects. Noninvasive tear film breakup time was measured using a new method based on a corneal topographer equipped with a modified scan software. The correlations between the NI-BUT, age, and gender were determined. RESULTS: In total, a significant difference between the NI-BUT and the FBUT was found (4.9 ± 2.4 seconds vs. 9.0 ± 3.0 seconds; p < 0.001). No statistically significant difference in the NI-BUT was observed between the male and female subjects (5.5 ± 2.0 seconds vs. 4.5 ± 2.5 seconds; p = 0.137). In addition, no significant correlation was detected between the NI-BUT and age (0.143, p = 0.321). CONCLUSIONS: The NI-BUT values found in this study are much lower than those of previous reports. Our results show no significant differences in tear film stability with age. The tear physiology of the Chinese population may not be the same as in Western populations.
Freitag SK, Lee H, Lee NG, Johnstone MA, Sires BS. Retrospective review of eyelash number in patients who have undergone full-thickness eyelid resection. Ophthalmic Plast Reconstr Surg 2014;30(1):1-6.Abstract
PURPOSE: The purpose of this study was to determine whether a localized full-thickness eyelid excision results in a proportional decrease in the total number of eyelashes or whether a full complement of visible lashes persists, thus suggesting a compensatory increase in the anagen/telogen ratio among the remaining follicles. METHODS: A retrospective chart review was performed on 38 patients who underwent full-thickness eyelid resections repaired with primary eyelid closure for either benign or malignant eyelid lesions. Demographic and surgical data were collected, postoperative eyelid photographs were reviewed, and eyelashes were counted. RESULTS: There were 10 upper eyelids and 28 lower eyelids in 10 men and 28 women, with an average age of 57.9 years (range, 14-86 years). The lesion pathology was benign in 21 cases (55%) and malignant in 17 cases (45%). The full-thickness defect involved <25% of the eyelid in 16 cases (42%) and >25% of the eyelid in 22 cases (58%). The follow-up period ranged from 50 to 319 days, with an average of 94 days. In contralateral controls, upper eyelids had an average of 72.1 lashes and lower eyelids had an average of 38.2 lashes, and there was no statistical significance between men and women. In lower lids that underwent <25% resection, control lids had an average of 37.3 lashes and operative lids had 37.1 lashes. In lower lids that underwent >25% resection, control lids had an average of 38.7 lashes and operative lids had 34.2 lashes. This represents an 11.6% decrease and was statistically significant. In upper eyelids that underwent <25% resection and >25% resection, control eyelids had an average of 74.9 lashes and 69.3 lashes and operative eyelids had 77.6 lashes and 69.1 lashes, respectively. Finally, lash count was compared by benign versus malignant pathologic diagnosis. In upper eyelids with benign lesions and malignant lesions, control eyelids had an average of 73.8 lashes and 65.3 lashes and operative eyelids had 74.6 lashes and 68.3 lashes, respectively. In lower eyelids with benign pathology and malignant lesions, control eyelids had an average of 34.5 lashes and 41.4 lashes and operative eyelids had 33.8 lashes and 36.8 lashes. This represents an 11.1% decrease and was statistically significant. CONCLUSIONS: Full-thickness excision of eyelid margin tissue including lashes does not usually affect postoperative lash numbers. Because the total number of follicles is reduced, the percentage of lashes in the anagen versus the resting or telogen phase apparently increases compared with the preoperative state. This eyelash study contributes to the growing body of literature on the poorly understood topic of hair follicle cycle regulation.
Kruh JN, Yang P, Suelves AM, Foster SC. Infliximab for the treatment of refractory noninfectious Uveitis: a study of 88 patients with long-term follow-up. Ophthalmology 2014;121(1):358-364.Abstract
OBJECTIVE: To establish the safety and efficacy of infliximab for the treatment of refractory noninfectious uveitis. DESIGN: Retrospective, interventional, noncomparative cohort study. PARTICIPANTS: Eighty-eight patients from a single-center private practice. METHODS: Patients with chronic, recalcitrant uveitis treated with infliximab (Remicade; Janssen Biotech, Inc., Titusville, NJ) were identified through an electronic medical record database. All charts were reviewed for sex, diagnosis, location of inflammation, presence of vasculitis, prior immunomodulatory treatments, duration of infliximab treatment, dose received, secondary side effects, and other medications continued while receiving treatment with infliximab. MAIN OUTCOME MEASURES: The primary outcome measures were the rate of remission, time to remission, relapse rate, failure rate, and patient tolerance. Additional analysis aimed to identity risk factors that would predict a higher success rate of infliximab to treat various types of noninfectious uveitis. RESULTS: Of the 72 patients (81.8%) who achieved clinical remission while being treated with infliximab, 42 (58.3%) required additional immunomodulatory medications. At 7, 18.1, and 44.7 weeks, 25%, 50%, and 75% of patients, respectively, achieved clinical remission off all corticosteroids. Thirty-two patients (36.4%) experienced at least 1 side effect while on infliximab therapy, and 17 patients (19.3%) discontinued treatment secondary to 1 or more intolerable side effects. The most common adverse effects were skin rash (9.1%) and fatigue (8%). Factors associated with a higher chance to achieve clinical remission were nonidiopathic uveitis (P < 0.001), intermediate or panuveitis (P < 0.001), absence of vasculitis (P < 0.001), and a starting dose ≥5 mg/kg (P < 0.011). CONCLUSIONS: Infliximab induces a high rate of complete clinical remission in recalcitrant uveitis and is well tolerated by most patients.
Kang JH, Loomis SJ, Yaspan BL, Bailey JC, Weinreb RN, Lee RK, Lichter PR, Budenz DL, Liu Y, Realini T, Gaasterland D, Gaasterland T, Friedman DS, McCarty CA, Moroi SE, Olson L, Schuman JS, Singh K, Vollrath D, Wollstein G, Zack DJ, Brilliant M, Sit AJ, Christen WG, Fingert J, Forman JP, Buys ES, Kraft P, Zhang K, Allingham RR, Pericak-Vance MA, Richards JE, Hauser MA, Haines JL, Wiggs JL, Pasquale LR. Vascular tone pathway polymorphisms in relation to primary open-angle glaucoma. Eye (Lond) 2014;28(6):662-71.Abstract
AIMS: Vascular perfusion may be impaired in primary open-angle glaucoma (POAG); thus, we evaluated a panel of markers in vascular tone-regulating genes in relation to POAG. METHODS: We used Illumina 660W-Quad array genotype data and pooled P-values from 3108 POAG cases and 3430 controls from the combined National Eye Institute Glaucoma Human Genetics Collaboration consortium and Glaucoma Genes and Environment studies. Using information from previous literature and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, we compiled single-nucleotide polymorphisms (SNPs) in 186 vascular tone-regulating genes. We used the 'Pathway Analysis by Randomization Incorporating Structure' analysis software, which performed 1000 permutations to compare the overall pathway and selected genes with comparable randomly generated pathways and genes in their association with POAG. RESULTS: The vascular tone pathway was not associated with POAG overall or POAG subtypes, defined by the type of visual field loss (early paracentral loss (n=224 cases) or only peripheral loss (n=993 cases)) (permuted P≥0.20). In gene-based analyses, eight were associated with POAG overall at permuted P<0.001: PRKAA1, CAV1, ITPR3, EDNRB, GNB2, DNM2, HFE, and MYL9. Notably, six of these eight (the first six listed) code for factors involved in the endothelial nitric oxide synthase activity, and three of these six (CAV1, ITPR3, and EDNRB) were also associated with early paracentral loss at P<0.001, whereas none of the six genes reached P<0.001 for peripheral loss only. DISCUSSION: Although the assembled vascular tone SNP set was not associated with POAG, genes that code for local factors involved in setting vascular tone were associated with POAG.
Jakobiec FA, Rai R, Yoon MK. Fibrous histiocytoma of the tarsus: clinical and immunohistochemical observations with a differential diagnosis. Cornea 2014;33(5):536-9.Abstract
PURPOSE: To describe the diagnostic clinical findings and immunopathology of a fibrous histiocytoma of the upper eyelid tarsus of a 42-year-old man. METHODS: Analysis of clinical features and results of histopathologic and immunohistochemical evaluations using antibodies against the biomarkers smooth muscle actin, S100, CD1a, CD3, CD20, CD31, CD34, CD68, CD163, factor XIIIa, adipophilin, androgen receptor, and Ki-67. RESULTS: The skin moved over a firm lesion that was situated in the tarsus and protruded from the palpebral conjunctiva as a whitish flat-domed noninflamed mass that had caused an irritating corneal epitheliopathy. Histopathologically, there was a storiform or spiral nebular growth pattern, a moderate amount of intercellular collagen, and no nuclear atypia or mitotic activity. The main immunohistochemical findings were CD34 and smooth muscle actin negativity among the tumor cells and a scarcity of CD68/163 histiocytes. Androgen receptors were identified in the tumor cells. CONCLUSIONS: CD34 histiocytoma of the tarsus is a rare, benign, and separate entity from a CD34 solitary fibrous tumor. Conservative tarsectomy is curative.
Hsu S-M, Mathew R, Taylor AW, Stein-Streilein J. Ex-vivo tolerogenic F4/80⁺ antigen-presenting cells (APC) induce efferent CD8⁺ regulatory T cell-dependent suppression of experimental autoimmune uveitis. Clin Exp Immunol 2014;176(1):37-48.Abstract
It is known that inoculation of antigen into the anterior chamber (a.c.) of a mouse eye induces a.c.-associated immune deviation (ACAID), which is mediated in part by antigen-specific local and peripheral tolerance to the inciting antigen. ACAID can also be induced in vivo by intravenous (i.v.) inoculation of ex-vivo-generated tolerogenic antigen-presenting cells (TolAPC). The purpose of this study was to test if in-vitro-generated retinal antigen-pulsed TolAPC suppressed established experimental autoimmune uveitis (EAU). Retinal antigen-pulsed TolAPC were injected i.v. into mice 7 days post-induction of EAU. We observed that retinal antigen-pulsed TolAPC suppressed the incidence and severity of the clinical expression of EAU and reduced the expression of associated inflammatory cytokines. Moreover, extract of whole retina efficiently replaced interphotoreceptor retinoid-binding protein (IRBP) in the preparation of TolAPC used to induce tolerance in EAU mice. Finally, the suppression of EAU could be transferred to a new set of EAU mice with CD8⁺ but not with CD4⁺ regulatory T cells (T(reg)). Retinal antigen-pulsed TolAPC suppressed ongoing EAU by inducing CD8⁺ T(reg) cells that, in turn, suppressed the effector activity of the IRBP-specific T cells and altered the clinical symptoms of autoimmune inflammation in the eye. The ability to use retinal extract for the antigen raises the possibility that retinal extract could be used to produce autologous TolAPC and then used as therapy in human uveitis.
Hansen RM, Tavormina JL, Moskowitz A, Fulton AB. Effect of retinopathy of prematurity on scotopic spatial summation. Invest Ophthalmol Vis Sci 2014;55(5):3311-3.Abstract
PURPOSE: To evaluate scotopic retinal organization in retinopathy of prematurity (ROP) through a study of spatial summation. METHODS: Thresholds for a range of stimulus diameters (0.4°-10°) were measured using a two alternative, spatial, forced choice psychophysical procedure. The critical diameter (DCRIT) for complete summation was estimated in subjects with a history of severe ROP (N = 7) and mild ROP (N = 17). Subjects who were born preterm and never had ROP (N = 16) and term-born subjects (N = 7) were also tested. The subjects ranged in age from 9 to 17 (median 13.5) years. RESULTS: Critical diameter for complete spatial summation was significantly larger in ROP subjects than in subjects who never had ROP and in term-born control subjects. Critical diameter varied significantly with severity of ROP. CONCLUSIONS: The larger DCRIT values in ROP are consistent with altered organization of the post receptor retina. This may offer the ROP retina a strategy for achieving noise reduction and good dark-adapted visual sensitivity.