Purpose: To establish a method allowing multifocal electroretinography (mfERG) recording with simultaneous fundus monitoring on anaesthetized pigs. In addition we characterize the peaks of the porcine mfERG trace, and compare the visual streak area with the optic nerve head, a known non-response area. Finally we illustrate the feasibility of the method by performing mfERG after an induced laser burn in the visual streak.
Methods: Fifteen pigs underwent mfERG recordings at baseline, and after 1 and 6 weeks of observation. One pig was evaluated before and after retinal diode laser treatment in the visual streak.
Results: The porcine mfERG trace appears similar to the human mfERG trace, and can be described by three peaks named N1, P1 and N2. Significantly faster implicit time was found in the visual streak regarding N1 (P < 0.001) than in areas outside the visual streak. Amplitudes of all three peaks were increased in the visual streak (P < 0.005). The laser-treated area was characterized by a response similar to what is found at the location of the optic nerve head.
Conclusion: Porcine mfERG is similar in appearance to the human response and can be described by the same three peaks. Significantly higher amplitudes of all three peaks are found in the visual streak when compared to the optic nerve head and inferior retina. We have detected the functional deficit caused by a laser burn at the size of 3 x 3 mm.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1600-0420.2006.00859.x | DOI Listing |
J Comput Assist Tomogr
January 2025
Department of Radiology, College of Medicine, University of Florida, Gainesville, FL.
Purpose: The purpose of this work was to evaluate the image quality of a commercial CT scanner equipped with a novel detector and filtration technology called PureVision Optics (PVO).
Methods: CT number, noise, contrast-to-noise ratio (CNR), modulation transfer function (MTF), and noise power spectrum (NPS) were assessed using the ACR CT Accreditation phantom scanned with various acquisitions at 80 kV, 100 kV, 120 kV, and 135 kV, each with multiple CTDIvol values of 20 mGy, 40 mGy, and 65 mGy. Artifacts were evaluated in an anthropomorphic head phantom, a cadaver head, and in patient studies.
Hum Brain Mapp
February 2025
Laboratory for Imaging Science and Technology, Department of Electrical and Computer Engineering, Seoul National University, Seoul, Republic of Korea.
Magnetic susceptibility source separation (χ-separation), an advanced quantitative susceptibility mapping (QSM) method, enables the separate estimation of paramagnetic and diamagnetic susceptibility source distributions in the brain. Similar to QSM, it requires solving the ill-conditioned problem of dipole inversion, suffering from so-called streaking artifacts. Additionally, the method utilizes reversible transverse relaxation ( ) to complement frequency shift information for estimating susceptibility source concentrations, requiring time-consuming data acquisition for (e.
View Article and Find Full Text PDFBMC Vet Res
January 2025
Department of Veterinary Pathobiology, College of Veterinary Medicine and Animals Sciences, University of Gondar, P.O. Box: 196, Gondar, Ethiopia.
Haemonchosis is a major gastrointestinal parasitic infection in sheep caused by H. contortus. An abattoir-based cross-sectional study was conducted from January to September 2024 to assess the haematobiochemical alterations and lesion characterization induced by haemonchosis in slaughtered sheep at Gondar ELFORA abattoir.
View Article and Find Full Text PDFOphthalmol Sci
November 2024
Department of Ophthalmology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
Purpose: Autologous retinal transplantation has been successfully employed in the treatment of large and myopic macular holes that are refractory to standard surgical treatments. Patients transplanted with a peripheral neurosensory retinal graft have shown unexpected improvements in visual acuity. The study aims to investigate if neural integration of the graft takes place in a porcine model of retinal hole.
View Article and Find Full Text PDFOphthalmic Genet
December 2024
Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida, USA.
Background: Pseudoxanthoma elasticum (PXE) is characterized by aberrant calcification of elastic tissues throughout the body causing varying degrees of skin, cardiac, and ocular disease. Although PXE is classically regarded as an autosomal recessive disease, recent reports have demonstrated a haploinsufficiency phenotype, in which carriers of monoallelic ATP-binding cassette transporter () gene mutations demonstrate mild manifestations of PXE. In this case report, we describe a patient with a monoallelic mutation and atypical angioid streaks.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!