8 research outputs found
A multisource approach for coastline mapping and identification of shoreline changes
Coastal dynamics are driven by phenomena of exogenous and endogenous nature. Characterizing factors that influence
their equilibrium and continuous monitoring are fundamental for effective environmental planning and
management of coastal areas. In order to monitor shoreline changes, we developed a methodology based on a
multisource and multitemporal approach. A database, related to the Ionian coast of Basilicata region (about 50
km), was implemented by using cartographic data (IGMI data), satellite imagery (SPOT-PX/XS, Landsat-TM,
Corona) and aerial data covering the period form 1949 to 2001. In particular, airborne data (1 m spatial resolution)
were acquired during a specific campaign we performed in 2000 and 2001. To obtain the best performance
from the available data, we applied a data fusion procedure on visible and thermal information. Different algorithms
were tested, such as band ratios and clustering for extracting the coastline. The best results from multispectral
data were obtained using a threshold algorithm we devised by exploiting the green, red and NIR bands,
whereas for panchromatic data we selected clustering as the more suitable method. Moreover, a GPS survey was
performed to evaluate the influence of tidal effects
Association of Neuroretinal Thinning and Microvascular Changes with Hypertension in an Older Population in Southern Italy
Background: Retinal microvasculature assessment at capillary level may potentially aid the evaluation of early microvascular changes due to hypertension. We aimed to investigate associations between the measures obtained using optical coherence tomography (OCT) and OCT-angiography (OCT-A) and hypertension, in a southern Italian older population. Methods: We performed a crosssectional analysis from a population-based study on 731 participants aged 65 years+ subdivided into two groups according to the presence or absence of blood hypertension without hypertensive retinopathy. The average thickness of the ganglion cell complex (GCC) and the retinal nerve fiber layer (RNFL) were measured. The foveal avascular zone area, vascular density (VD) at the macular site and of the optic nerve head (ONH) and radial peripapillary capillary (RPC) plexi were evaluated. Logistic regression was applied to assess the association of ocular measurements with hypertension. Results: GCC thickness was inversely associated with hypertension (odds ratio (OR): 0.98, 95% confidence interval (CI): 0.97–1). A rarefaction of VD of the ONH plexus at the inferior temporal sector (OR: 0.95, 95% CI: 0.91–0.99) and, conversely, a higher VD of the ONH and RPC plexi inside optic disc (OR: 1.07, 95% CI: 1.04–1.10; OR: 1.04, 95% CI: 1.02–1.06, respectively) were significantly associated with hypertension. Conclusion: A neuroretinal thinning involving GCC and a change in capillary density at the peripapillary network were related to the hypertension in older patients without hypertensive retinopathy. Assessing peripapillary retinal microvasculature using OCT-A may be a useful non-invasive approach to detect early microvascular changes due to hypertension
Combined Topography-Guided Trans-Epithelial PRK and PTK for Recalcitrant Recurrent Corneal Erosions in Lattice Corneal Distrophy
Francesco Pignatelli,1 Fedele Passidomo,1 Rosa Buonamassa,2 Alfredo Niro,1 Giuseppe Addabbo1 1Eye Clinic, “SS. Annunziata” Hospital, ASL Taranto, Taranto, Italy; 2Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari “Aldo Moro”, Bari, ItalyCorrespondence: Fedele Passidomo, Eye Clinic, “SS. Annunziata” Hospital, ASL Taranto, Via Francesco Bruno, 1, Taranto, 74121, Italy, Tel +39 3288569125, Email [email protected]: To report morphologic and functional changes after topography-guided trans-epithelial photorefractive keratectomy (PRK) combined with phototherapeutic keratectomy (PTK) for recalcitrant recurrent corneal erosions in Lattice Corneal Dystrophy (LCD).Methods: One case report.Results: A 78-year-old man presented us with decreased visual acuity [20/100 in right eye (RE), and 20/400 in left eye (LE)], and redness with foreign body sensation in both eyes. Clinical examination revealed epithelial erosions, and linear stromal opacities involving the center of the cornea in both eyes, supporting the diagnosis of LCD. Several medical approaches including autologous serum, amniotic membrane extract, and nerve growth factor eye drops allowed a temporary improvement in symptoms. A single-step topography-guided trans-epithelial PRK combined with PTK (CIPTA® 2 software, iVis Technologies) was performed in both eyes. After surface ablation using PRK, PTK was performed using masking agents (1% hydroxy-methylcellulose) to smooth the ablated surface. Subsequently, 0.02% Mitomycin C was applied over the ablated surface. At the 3-month follow-up, a resolution of corneal erosions, and stromal opacities were observed in both eyes, with a visual improvement to 20/25 in the RE and 20/50 in the LE. Furthermore, spherical equivalent, keratometric astigmatism, and corneal morphological irregularity index improved.Conclusion: Recalcitrant corneal erosions and stromal opacities in LCD may be successfully treated using combined topography-guided trans-epithelial PRK and PTK.Keywords: corneal dystrophy, recurrent corneal erosions, phototherapeutic keratectomy, topography-guided photorefractive keratectom
A multisource approach for coastline mapping and identification of shoreline changes
Coastal dynamics are driven by phenomena of exogenous and endogenous nature. Characterizing factors that influence
their equilibrium and continuous monitoring are fundamental for effective environmental planning and
management of coastal areas. In order to monitor shoreline changes, we developed a methodology based on a
multisource and multitemporal approach. A database, related to the Ionian coast of Basilicata region (about 50
km), was implemented by using cartographic data (IGMI data), satellite imagery (SPOT-PX/XS, Landsat-TM,
Corona) and aerial data covering the period form 1949 to 2001. In particular, airborne data (1 m spatial resolution)
were acquired during a specific campaign we performed in 2000 and 2001. To obtain the best performance
from the available data, we applied a data fusion procedure on visible and thermal information. Different algorithms
were tested, such as band ratios and clustering for extracting the coastline. The best results from multispectral
data were obtained using a threshold algorithm we devised by exploiting the green, red and NIR bands,
whereas for panchromatic data we selected clustering as the more suitable method. Moreover, a GPS survey was
performed to evaluate the influence of tidal effects