Search results for "optical"

Anterior chamber depth measurement in teenagers. Comparison of two techniques

2013

Purpose: The aim of this study is to determine the anterior chamber depth (ACD) in teenagers using two different devices: partial coherence interferometry IOLMaster (Carl Zeiss Meditec) and anterior segment optical coherence tomography (Visante TM OCT, Carl Zeiss Meditec) and to evaluate the degree of agreement between ACD measurements carried out by both instruments. Methods: In this prospective study 68 eyes of 34 emmetropic Caucasic patients (18 girls and 16 boys) were analysed. ACD was measured from the anterior corneal surface to anterior surface of the crystalline lens. For each age the ACD size was calculated and the difference between IOLMaster and Visante-OCT measurements was analy…

Does Posterior Capsule Opacification Affect the Results of Diagnostic Technologies to Evaluate the Retina and the Optic Disc?

2014

The visual outcome obtained after cataract removal may progressively decline because of posterior capsular opacification (PCO). This condition can be treated by creating an opening in the posterior lens capsule by Nd:YAG laser capsulotomy. PCO optical imperfections cause several light reflection, refraction, and diffraction phenomena, which may interfere with the functional and structural tests performed in different ocular locations for the diagnosis and follow-up of ocular disease, like macular and optic nerve diseases. Some parameters measured by visual field examinations, scanning laser polarimetry, and optical coherence tomography (OCT) have changed after PCO removal. Imaging quality a…

Analysis of the Peripapillary and Macular Regions Using OCT Angiography in Patients with Schizophrenia and Bipolar Disorder

2021

Purpose: To measure RNFL and vasculature around the optic disc and in the macula in patients with schizophrenia (SZ) and bipolar disorder (BD) using optical coherence tomography angiography (OCTA). Methods: 24 eyes of patients with SZ and 16 eyes of patients with BD as well as 30 eyes of healthy subjects were examined with OCTA. The radiant peripapillary capillary (RPC) density and RNFL thickness were measured in the peripapillary area. Moreover, macular thickness and vessel density were measured in both superficial and deep layers. Results: Significantly decreased values of vessel density in the macular deep vascular complex were found in the eyes of patients with SZ, compared to BD and th…

Advanced Endoscopic Imaging Methods

2021

Endoscopic imaging is the mainstay of gastrointestinal endoscopy and has experienced remarkable improvements in recent decades. Further endoscopic innovations stemming from major technological advances such as artificial intelligence and deep learning are at advanced stages of development and will be increasingly deployed in routine clinical practice. These will improve the detection and enable real-time optical diagnosis of pathologies in the gastrointestinal tract. Furthermore, the utilization of endoscopic robots may result in higher diagnostic yield and greater patient comfort. This chapter covers the most recent developments around computer-assisted diagnosis, hypoxia and three-dimensi…

Colonoscopy, Tumors, and Inflammatory Bowel Disease - New Diagnostic Methods

2006

Accurate detection of premalignant lesions and early cancers in the colon is essential for curative endoscopic or surgical therapy, since the prognosis for the affected patients is closely related to the size and stage of the neoplastic lesion. Total colonoscopy is the accepted gold standard for screening and surveillance of colorectal cancer. This review summarizes recently published diagnostic developments and key findings in the areas of colonoscopy, colonic tumors, and inflammatory bowel diseases. Relevant findings have been reported for chromo-endoscopy in the diagnosis of colitis-associated neoplasia, as well as flat and depressed adenomas. Real-time Doppler capabilities have now been…

Befunde der optischen Kohärenztomografie (OCT) bei Behandlung einer submakulären Blutung durch ein retinales Makroaneurysma mit intravitrealer Injekt…

2015

New intraocular lens for achromatizing the human eye.

2007

To describe the design of a new intraocular lens (IOL) capable of correcting spherical and chromatic aberrations when implanted in the human eye.University of Murcia, Murcia, and University of Valencia, Valencia, Spain.A hybrid singlet achromatic IOL was designed. The IOL has a combination of a refractive and a diffractive surface, with 1 of the surfaces being aspherical. Optical simulations were used to model the polychromatic modulation transfer function (MTF) in pseudophakic eyes to explain the differences in optical quality afforded by the achromatic IOL. Parameters such as focus shift, optical path difference, through-focus, and robustness to tilt and decentering of achromatic IOLs wer…

Perfluoroalkylated amphiphilic MUC1 glycopeptide antigens as tools for cancer immunotherapy.

2010

The synthesis of perfluoroalkylated glycopeptide antigens and their specific binding to anti-MUC1 mouse antibodies is reported.

Melting point, molecular symmetry and aggregation of tetrachlorobenzene isomers: the role of halogen bonding

2018

Tetrachlorobenzenes represent one of the best known, but not yet fully understood, group of isomers of the structure–melting point relationship. The differences in melting temperatures of these structurally related compounds were rationalized in terms of the hierarchy and nature of formed noncovalent interactions, and the molecular aggregation that is influenced by molecular symmetry. The highest melting point is associated with the highly symmetric 1,2,4,5-tetrachlorobenzene isomer. The structures of less symmetrical 1,2,3,4-tetrachlorobenzene and 1,2,3,5-tetrachlorobenzene, determined at 270 and 90 K, show a distinct pattern of halogen bonds, characterized by the different numbers and typ…

Decomposition Process of Carboxylate MOF HKUST-1 Unveiled at the Atomic Scale Level

2016

HKUST-1 is a metal-organic framework (MOF) which plays a significant role both in applicative and basic fields of research, thanks to its outstanding properties of adsorption and catalysis but also because it is a reference material for the study of many general properties of MOFs. Its metallic group comprises a pair of Cu2+ ions chelated by four carboxylate bridges, forming a structure known as paddle-wheel unit, which is the heart of the material. However, previous studies have well established that the paddle-wheel is incline to hydrolysis. In fact, the prolonged exposure of the material to moisture promotes the hydrolysis of Cu-O bonds in the paddle-wheels, so breaking the crystalline n…