Owhofasa Agbedia

New Treatment Options for Noninfectious Uveitis

Autoimmune uveitis is a group of sight-threatening inflammatory diseases associated with an exacerbated immunological response to ocular proteins. The Standardization of Uveitis Nomenclature Working Group Guidelines have recommended the use of corticosteroids as the first line of therapy for patients who present with active uveitis. However, long-term use of corticosteroids is associated with numerous adverse effects including cataract, glaucoma and metabolic disorders. In this context, new drugs developed to treat rheumatic diseases, and other autoimmune diseases, are being employed often as monotherapy or combined with other immunosuppressive drugs in order to decrease the corticosteroid burden on patients and to manage refractive uveitis. These drugs are currently being evaluated in the framework of uveitis and may open a new horizon with less side effects and more responsiveness for chronic cases. Among others, calcineurin inhibitor voclosporin, mammalian target of rapamycin inhibitor sirolimus, and the IL-1 trap rilonacept, are among these new agents and will be scrutinized in detail in this chapter. More efficient modes of drug delivery are also being employed to deliver high concentration of drug locally and to minimize systemic side effects. The new modes of drug delivery that we will describe in the index chapter include nanoparticles and iontophoresis.

Blunted diurnal decline of cortisol among older adults with low socioeconomic status

Low socioeconomic status (SES) is associated with increased risk for adverse health outcomes; those with low SES are thought to experience greater environmental disadvantage and exposure to chronic stress over the life course. The effects of chronic stress on health have been measured by cortisol levels and variations in their diurnal pattern. However, the patterns of association between SES and cortisol have been equivocal in older adults. This paper examined in 98 older adults participating in the Brain Health Substudy of the Baltimore Experience Corps Trial baseline patterns of diurnal variation in salivary cortisol associated with lower versus higher SES using total income and perceived SES relative to others. For each measure, participants stratified into lower versus higher SES showed a more blunted rate of decline in diurnal salivary cortisol over the day in adjusted models (P values ≤ 0.05). There were no SES‐related differences in awakening cortisol, cortisol‐awakening response, or area under the curve. These findings confirm prior evidence of a biologic pathway through which socioeconomic disadvantage is linked to biologic vulnerability, and through which the impact of volunteer service in Experience Corps may be measured.

Quantitative assessment of Diabetic Macular Edema using fluorescein leakage maps

Diagnosis of Diabetic Macular Edema (DME) from Fundus Fluorescein Angiography (FFA) image sequences is a standard clinical practice. Nevertheless, current methods depend on subjective evaluation of the amount of fluorescein leakage in the images which lack reproducibility and require well-trained grader. In this work, we present a method for processing FFA images to generate a fluorescein leakage map that can be used for quantitative evaluation of DME. An essential step in the proposed method is to model the spatial distribution of the image intensity within the macula. This model, which represents the non-leaking structures, is then subtracted from the late timeframe image to enhance the areas of fluorescein leakage. The resulting difference image is then mapped with empirical linear transformation to produce a color Fluorescein Leakage Map (FLM) that can be used for quantitative assessment and detection of DME. The method was applied to 13 image sequences for 13 different patients. The resulting FLM maps were found to be correlated with the thickness maps produced by Optical Coherence Tomography (OCT). The relatively high correlation between the FLM and OCT maps show the potential and of using the developed method for quantitatively assess the DME in FFA image sequences.

Comparison of optical quality after implantable collamer lens implantation and wavefront-guided laser in situ keratomileusis

AIM To compare the optical quality after implantation of implantable collamer lens (ICL) and wavefront-guided laser in situ keratomileusis (WG-LASIK). METHODS The study included 40 eyes of 22 patients with myopia who accepted ICL implantation and 40 eyes of 20 patients with myopia who received WG-LASIK. Before surgery and three months after surgery, the objective scattering index (OSI), the values of modulation transfer function (MTF) cutoff frequency, Strehl ratio, and the Optical Quality Analysis System (OQAS) values (OVs) were accessed. The higher order aberrations (HOAs) data including coma, trefoil, spherical, 2nd astigmatism and tetrafoil were also obtained. For patients with pupil size <6 mm, HOAs data were analyzed for 4 mm-pupil diameter. For patients with pupil size ≥6 mm, HOAs data were calculated for 6 mm-pupil diameter. Visual acuity, refraction, pupil size and intraocular pressures were also recorded. RESULTS In both ICL and WG-LASIK group, significant improvements in visual acuities were found postoperatively, with a significant reduction in spherical equivalent (P< 0.001). After the ICL implantation, the OSI decreased slightly from 2.34±1.92 to 2.24±1.18 with no statistical significance (P=0.62). While in WG-LASIK group, the OSI significantly increased from 0.68±0.43 preoperatively to 0.91±0.53 postoperatively (Wilcoxon signed ranks test, P=0.000). None of the mean MTF cutoff frequency, Strehl ratio, OVs showed statistically significant changes in both ICL and WG-LASIK groups. In the ICL group, there were no statistical differences in the total HOAs for either 4 mm-pupil or 6 mm-pupil. In the WG-LASIK group, the HOA parameters increased significantly at 4 mm-pupil. The total ocular HOAs, coma, spherical and 2nd astigmatism were 0.12±0.06, 0.06±0.03, 0.00±0.03, 0.02±0.01, respectively. After the operation, these values were increased into 0.16±0.07, 0.08±0.05, -0.04±0.04, 0.03±0.01 respectively (Wilcoxon signed ranks test, all P<0.05). At 6 mm-pupil, the induction of total HOAs was not statistically significant in the WG-LASIK group. CONCLUSION ICL implantation has a less disturbance to optical quality than WG-LASIK. The OQAS is a valuable complementary measurement to the wavefront aberrometers in evaluating the optical quality.