Browsing by Author "Atalar, Ergin"
Now showing items 1-20 of 87
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Absolute temperature monitoring using RF radiometry in the MRI scanner
(Institute of Electrical and Electronics Engineers, 2006)Temperature detection using microwave radiometry has proven value for noninvasively measuring the absolute temperature of tissues inside the body. However, current clinical radiometers operate in the gigahertz range, which ... -
Accelerating the co-simulation method for the design of transmit array coils for MRI
(Springer, 2021-02)Although the co-simulation method dramatically reduces the complexity of the design of TxArray coils, finding the optimum solution is not trivial since there exist many local minima in the optimization problem. We propose ... -
Accelerating the co-simulation method for the design of transmit array coils for MRI
(Springer, 2020)Objective: Accelerating the co-simulation method for the design of transmit array (TxArray) coils is studied using equivalent circuit models. Materials and methods: Although the co-simulation method dramatically reduces ... -
Active decoupling of RF coils using a transmit array system
(Springer Verlag, 2015)Objective: Implementation of a decoupling method for isolation of transmit and receive radio frequency (RF) coils for concurrent excitation and acquisition (CEA) MRI in samples with ultra-short T2*. Materials and methods: ... -
Analysis and mitigation of noise in simultaneous transmission and reception in MRI
(John Wiley & Sons, Inc., 2021-03-05)Purpose In simultaneous transmission and reception (STAR) MRI, along with the coupling of the excitation pulse to the received signal, noise, and undesired distortions (spurs) coming from the transmit chain also leak into ... -
Analysis of B1 mapping by Bloch Siegert Shift
(ISMRM, 2012)In this study, B1 mapping by the Bloch-Siegert shift is analyzed with simulations and experiments. The importance of the pulse duration and the crusher gradients are investigated. It is shown that the off-resonance pulse ... -
Analysis of B1 mapping by Bloch Siegert shift
(ISMRM, 2012-05)The Bloch-Siegert shift is a new phase-based B1 mapping method [1]. This method utilizes the fact that for a large off-resonance frequency, square of the B1 field magnitude is proportional to the phase. In this study, ... -
Analytic expressions for the ultimate intrinsic signal-to-noise ratio and ultimate intrinsic specific absorption rate in MRI
(Wiley, 2011-03-09)The ultimate intrinsic signal-to-noise ratio is the highest possible signal-to-noise ratio, and the ultimate intrinsic specific absorption rate provides the lowest limit of the specific absorption rate for a given flip ... -
Approximate fourier domain expression for bloch-siegert shift
(John Wiley and Sons Inc., 2015)Purpose: In this study, a newsimple Fourier domain-based analytical expression for the Bloch-Siegert (BS) shift-based B1 mapping method is proposed to obtain |B1+| more accurately while using short BS pulse durations and ... -
A catheter tracking method using reverse polarization for MR‐guided interventions
(John Wiley & Sons, Inc., 2007)To conduct interventional procedures in MRI, reliable visualization of interventional devices such as catheters is necessary. For this purpose, the use of inductively-coupled radio frequency (ICRF) coils has been proposed. ... -
Comments on "Ensuring Safety of Implanted Devices Under MRI Using Reversed Polarization"
(Wiley, 2011-10-24) -
Decreasing SAR of a multi-dimensional central brightening inhomogeneity correction pulse using nonlinear gradient fields and VERSE
(ISMRM, 2012-05)To correct for B1 inhomogeneity artifacts, multi-dimensional pulses are widely used. However, such pulses increase SAR significantly. In this study, we compare, and combine two SAR reduction methods, the variable rate ... -
Design of a Gd-DOTA-phthalocyanine conjugate combining MRI contrast imaging and photosensitization properties as a potential molecular theranostic
(Wiley-Blackwell Publishing, Inc., 2014)The design and synthesis of a phthalocyanine - Gd-DOTA conjugate is presented to open the way to novel molecular theranostics, combining the properties of MRI contrast imaging with photodynamic therapy. The rational design ... -
Design of a novel MRI compatible manipulator for image guided prostate interventions
(IEEE, 2005-02)This paper reports a novel remotely actuated manipulator for access to prostate tissue under magnetic resonance imaging guidance (APT-MRI) device, designed for use in a standard high-field MRI scanner. The device provides ... -
Design of internal MRI coils using ultimate intrinsic SNR
(Springer, 2009-09-27)Object: Internal MRI coils have important applications in diagnostic and interventional studies. Since they can be placed very close to the region of interest in the body, they are favored over external coils in applications ... -
Detection of MR signal during RF excitation using a transmit array system
(ISMRM, 2012-05)Most of conventional MRI applications are based on a time interleaved approach for RF excitation and signal detection. The idea of concurrent RF excitation and reception was implemented in a few recent studies using sideband ... -
Eigenmode analysis of the scattering matrix for the design of MRI transmit array coils
(International Society for Magnetic Resonance in Medicine, 2021)To obtain efficient operation modes of transmit array (TxArray) coils using a general design technique based on the eigenmode analysis of the scattering matrix. Methods We introduce the concept of modal reflected power ... -
Electrical circuit modeling of surface structures for X-ray photoelectron spectroscopic measurements
(Elsevier BV * North-Holland, 2008)We model the X-ray photoelectron spectrometer and the sample with lumped electrical circuit elements, and simulate various types of conditions using a widely used computer program (PSpice) and compare the results with ... -
Electrical impedance tomography of translationally uniform cylindrical objects with general cross-sectional boundaries
(Institute of Electrical and Electronics Engineers, 1990)An algorithm is developed for electrical impedance tomography (EIT) of finite cylinders with general cross-sectional boundaries and translationally uniform conductivity distributions. The electrodes for data collection are ...
