BONano 2017 Abstracts


Short Papers
Paper Nr: 1
Title:

Layer-by-layer Assembled Films for Ocular Drug Delivery

Authors:

Mónica Araújo, Jorge Morgado and Quirina Ferreira

Abstract: In this paper we describe a simple and versatile method to prepare drug delivery films composed of an ocular drug used in glaucoma treatment, brimonidine, which was encapsulated in a polymer-beta cyclodextrin. The films were developed in order to allow a controlled sequential release during long periods of time. Here we show that by introducing barrier layers of graphene oxide between the drug delivery ones it is possible to delay the brimonidine release for a few days. The time interval between two dosages of drug release will be controlled by adjusting the number and/or thickness of the graphene layers.

Paper Nr: 2
Title:

New Trends for Early Diabetic Retinopathy Diagnosis

Authors:

Joana Tavares Ferreira and Luís Abegão Pinto

Abstract: Diabetes Mellitus is one of the most common chronic diseases in the world and is a critical public health problem that could even be considered a pandemic. The diabetic retinopathy is the leading cause of blindness in adults. Diabetic retinopathy is now considered to be a new neurodegenerative disease. In fact, retinal neurodegeneration is present before any microcirculatory abnormalities can be detected in ophthalmoscopy. Functional studies documenting electroretinogram abnormalities, loss of dark adaptation, contrast sensitivity and colour vision and abnormal microperimetry that occur before any vascular abnormality. Novel imaging optical devices have allowed that this pre-vascular damage to be quantified in a non-invasive and reproducible way with retinal layer and choroidal thickness measurement.

Paper Nr: 3
Title:

Alzheimer Disease: OCT Retinal and Choroidal Thickness

Authors:

João Paulo Cunha and António Castanheira-Dinis

Abstract: The aim of this study is to compare macular retinal layers and choroidal thicknesses of patients with Alzheimer’s disease (AD) with those of patients without other known ophthalmological pathology, using spectral domain optical coherence tomography. Multiple linear regression analysis was applied to assess the effects of age, gender, spherical equivalent, visual acuity, intraocular pressure, axial length and mean arterial pressure on macular retinal layers thickness. Fifty eyes of 50 patients (mean age 73.10; SD=5.36 years) with a diagnosis of mild AD and 152 eyes of 152 patients without AD (mean age 71.03; SD=4.62 years) were included. There was a thinning in the peripheral ring of the ganglion cell layer (GCL) in the AD group (S6 p < 0.001; T6 and N6 p = 0.001). In the superior sectors of the inner plexiform layer (IPL), differences between the two groups also remained statistically significant after Bonferroni correction (S3 p = 0.001 and S6 p < 0.001). In the outer layers we did not observe differences statistically significant for AD group. These layers’ thicknesses were associated with statistical significance with gender (in inner and outer nuclear layers), age and choroidal thickness (CT) (in photoreceptor layer). In the AD patients group, CT was significantly thinner than in the first group of patients without AD, in all 13 locations (p<0.001), and age was relevant factor. Patients with AD showed a significant reduction in retinal layers and choroidal thickness. The thinnest macular measurements were found mostly in the inner layers, GCL and IPL, at superior sectors (pericentral and peripheral rings). This thinning may reflect a retinal characteristic of AD, related with both primary retinal lesion and transsynaptic retrograde degeneration and the choroidal thinning probably reflects the importance of vascular factors in the pathogenesis of this disease.

Paper Nr: 4
Title:

Morphology of Trabeculectomy Filtering Blebs using Anterior Segment Optical Coherence Tomography: A Comparison of Two Methods

Authors:

Rita Pinto Proença, Joana Ferreira and João Paulo Cunha

Abstract: Anterior segment imaging optical coherence tomography (AS-OCT) can be a useful aid in glaucoma surgery. Recent studies have shown its importance in both the preoperative morphologic evaluation of glaucoma patients as well as postoperative evaluation of filtering bleb functionality. Our purpose is to evaluate posttrabeculectomy filtering and non-filtering bleb characteristics in both time-domain OCT (TD-OCT, Visant™, Carl Zeiss) and spectral-domain OCT (SD-OCT, Heidelberg Spectralis ® anterior segment module), assess the usefulness of AS-OCT in evaluating postoperative filtering bleb function and compare both methods results.