Optimizing OCT acquisition parameters for assessments of vitreous haze for application in uveitis

Detection and evaluation of inflammatory activity in uveitis is essential to the management of the condition, and yet continues to be largely dependent on subjective clinical measures. Optical coherence tomography (OCT) measurement of vitreous activity is an alternative to clinical vitreous haze scoring and has passed a number of early validation studies. In this study we aimed to evaluate the impact of ‘operator factors’ on the variability of the technique as part of the validation process, and to help evaluate its suitability for ‘real world’ use. Vitreous haze index was calculated as a ratio between the reflectivity of the vitreous and of the outer retina in each scan. Different scanning conditions were tested and their effect on the measurement is reported. Our results show that the ‘quantitative imaging’ technique of OCT-measured vitreous activity had good reliability in normal subjects under a range of ‘real world’ conditions, such as when the operator changes the averaging value. The technique was however vulnerable to highly inaccurate focussing or abnormal downward displacement of the image. OCT-based quantification of vitreous activity is a promising alternative to current subjective clinical estimates, with sufficient ‘tolerance’ to be used in routine clinical practice as well as clinical trials

Macular sensitivity and fixation patterns in normal eyes and eyes with uveitis with and without macular edema

PURPOSE: This study aims to investigate the relationship between macular sensitivity and thickness in eyes with uveitic macular edema (UME). DESIGN: This study is a prospective observational case series. METHODS: The setting for this study was clinical practice. The study included 59 (28 with UME, 31 without UME) eyes of 26 patients with uveitis and 19 eyes of 10 normal subjects. The procedure followed was fundus-related perimetry and retinal thickness map with an automated fundus perimetry/tomography system. Main outcome measures included quantification of macular sensitivity, fixation pattern, and relationship between macular sensitivity and thickness. RESULTS: Fixation stability revealed that 56 eyes (93.44%) had stable fixation (\u3e75% within the central 2° of point of fixation); three eyes (6.56%) were relatively unstable (75% located within 4°); and no eye had unstable fixation (50% of fixation point within 0.5 mm of foveal center); seven eyes (11.86%) had peri-central fixation location (25% \u3c 50% within 0.5 mm); and seven eyes (11.86%) had eccentric (280 μm. CONCLUSIONS: Perimetry quantification of macular sensitivity and retinal thickness, in association with other factors, may offer novel information regarding the impact of UME on retinal function

Much Ado About the TPP’s Effect on Pharmaceuticals

Ocular antigens are sequestered behind the blood-retina barrier and the ocular environment protects ocular tissues from autoimmune attack. The signals required to activate autoreactive T cells and allow them to cause disease in the eye remain in part unclear. In particular, the consequences of peripheral presentation of ocular antigens are not fully understood. We examined peripheral expression and presentation of ocular neo-self-antigen in transgenic mice expressing hen egg lysozyme (HEL) under a retina-specific promoter. High levels of HEL were expressed in the eye compared to low expression throughout the lymphoid system. Adoptively transferred naïve HEL-specific CD4+ T cells proliferated in the eye draining lymph nodes, but did not induce uveitis. By contrast, systemic infection with a murine cytomegalovirus (MCMV) engineered to express HEL induced extensive proliferation of transferred naïve CD4+ T cells, and significant uveoretinitis. In this model, wild-type MCMV, lacking HEL, did not induce overt uveitis, suggesting that disease is mediated by antigen-specific peripherally activated CD4+ T cells that infiltrate the retina. Our results demonstrate that retinal antigen is presented to T cells in the periphery under physiological conditions. However, when the same antigen is presented during viral infection, antigen-specific T cells access the retina and autoimmune uveitis ensues

Characterisation of 11beta-hydroxysteroid dehydrogenase 1 in human orbital adipose tissue: a comparison with subcutaneous and omental fat.

Glucocorticoids (GCs) have a profound effect on adipose biology increasing tissue mass causing central obesity. The pre-receptor regulation of GCs by 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) that activates cortisol from cortisone has been postulated as a fundamental mechanism underlying the metabolic syndrome mediating adipocyte hyperplasia and hypertrophy in the omental (OM) depot. Orbital adipose tissue (OF) is the site of intense inflammation and tissue remodelling in several orbital inflammatory disease states. In this study, we describe features of the GC metabolic pathways in normal human OF depot and compare it with subcutaneous (SC) and OM depots. Using an automated histological characterisation technique, OF adipocytes were found to be significantly smaller (parameters: area, maximum diameter and perimeter) than OM and SC adipocytes (P<0 x 001). Although immunohistochemical analyses demonstrated resident CD68+ cells in all three whole tissue adipose depots, OF CD68 mRNA and protein expression exceeded that of OM and SC (mRNA, P<0 x 05; protein, P<0 x 001). In addition, there was higher expression of glucocorticoid receptor (GR)alpha mRNA in the OF whole tissue depot (P<0 x 05). Conversely, 11beta-HSD1 mRNA together with the markers of late adipocyte differentiation (FABP4 and G3PDH) were significantly lower in OF. Primary cultures of OF preadipocytes demonstrated predominant 11beta-HSD1 oxo-reductase activity with minimal dehydrogenase activity. Orbital adipocytes are smaller, less differentiated, and express low levels of 11beta-HSD1 but abundant GRalpha compared with SC and OM. OF harbours a large CD68+ population. These characteristics define an orbital microenvironment that has the potential to respond to sight-threatening orbital inflammatory disease

Labour productivity in Spain: 1977-2002

This study examines the evolution of labour productivity across Spanish regions during the period from 1977 to 2002. Applying the kernel technique, we estimate the effects of the transition process on labour productivity and its main sources. We find that Spanish regions experienced a major convergence process in labour productivity mostly driven by human capital in the 1977-1993 period. Conversely, the dynamics of investment in physical capital appear to be neutral with respect to the transition dynamics of labour productivity. Finally, from 1995 to 2002, no dynamic processes seemed to have taken place. Spanish regions exhibit a persistent relative position with established convergence clubs: the human capital effect is less important and the investment in physical capital seems not to have a triggering effect on labour productivity growth.

Instrument-based tests for measuring anterior chamber cells in uveitis: a systematic review protocol.

BACKGROUND Uveitis describes a group of inflammatory conditions affecting the eye. The ability to monitor inflammatory changes in anterior uveitis is crucial in clinical practice for making treatment decisions and in clinical trials for testing therapeutic agents. The current standard for quantifying anterior segment inflammation is clinical slit-lamp examination findings classified using the Standardisation of Uveitis Nomenclature (SUN) grading system. Such clinical grading systems rely on a subjective estimation using the slit lamp and are often non-linear and non-continuous scales, with large increases in cell count between each grade. Novel instrument-based technologies have emerged over the last few decades, which can provide objective and quantifiable measurements. This review will evaluate the reliability of such technologies and their level of agreement with anterior chamber (AC) cell count using clinical slit-lamp examination. METHODS Standard systematic review methodology will be used to identify, select and extract data from studies that report the use of any instrument-based technology in the assessment of AC cells. Searches will be conducted through bibliographic databases (MEDLINE, EMBASE and Cochrane Library), clinical trial registries and the grey literature. No restrictions will be placed on language or year of publication. The outcomes of interest are the correlation of index test measurements of AC cells with clinical grading systems using slit-lamp examination and the reliability of each index test identified. Quality assessment will be undertaken using QUADAS2. Degree of correlation between the index and reference test measures will be pooled and meta-analysed if appropriate. DISCUSSION A number of instrument-based tools are available for measuring AC cells. This review will evaluate the technologies available and measure the level of correlation of these alternative methods with clinical grading systems as well as their performance in reliability and repeatability. The findings of this review will identify those objective, instrument-based technologies which show good utility for measuring AC cells in a quantifiable way and which warrant further exploration for their sensitivity and reliability over the current standard. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42017084156 (Liu X, Moore DJ, Denniston AK). Instrument-based tests for measuring anterior chamber (AC) cells in uveitis: a systematic review. 2017). Study screening stage is complete. Data extraction stage has not yet commenced