Purpose: Passive resonators have been widely used in MRI to manipulate RF field distributions. However, optimizing these structures using full-wave electromagnetic (EM) simulations is computationally prohibitive, particularly for massive-element passive resonator arrays with many degrees of freedom. Methods: While EM and RF circuit co-simulation methods have previously been applied to RF coil design, this work presents a co-simulation framework specifically tailored for the analysis and optimization of passive resonators. The framework performs a single full-wave EM simulation in which the resonator’s lumped components are replaced by ports, followed by circuit-level computations to evaluate arbitrary capacitor/inductor configurations. This allows integration with a genetic algorithm to rapidly optimize the resonator parameters to enhance B1 fields in a targeted region of interest. Results: The proposed method was validated across three scenarios of increasing complexity: (1) a single-loop passive resonator on a spherical phantom, (2) a two-loop array on a cylindrical phantom, and (3) a two-loop array on a human head model. In all cases, the co-simulation results showed excellent agreement with full-wave EM simulations, with relative errors below 1%. The genetic-algorithm-driven optimization, involving tens of thousands of capacitor combinations, completed in under 5 minutes—whereas equivalent full-wave EM sweeps would require an impractically long computation time. Conclusion: To the best of our knowledge, this work represents the first systematic extension of the co-simulation methodology to passive resonator design, enabling fast, accurate, and scalable optimization. The approach significantly reduces computational burden while preserving full-wave accuracy, making it a powerful tool for passive RF structure development in MRI.

BackgroundHigh-density and flexible RF coils in MRI systems have greatly improved patient comfort and enhanced the signal-to-noise ratio (SNR) by better conforming to anatomical shapes and reducing weight. However, the feed boards in flexible coils often occupy large space and require many components, which can limit coil flexibility and integration.PurposeTo minimize the footprint of the feed board and reduce the number of components while maintaining effective common-mode suppression, this study introduces a compact one-inductor-three-capacitor (LCCC) lumped-element balun design.MethodsThe proposed LCCC balun consists of three capacitors and one inductor. Theoretical analysis based on Kirchhoff’s circuit laws was used to determine the optimal component values, and numerical simulations were conducted to verify the design performance. Prototypes for both 3 T and 7 T MRI were fabricated and experimentally evaluated.ResultsThe experimental results demonstrated negligible insertion loss and effective common-mode current suppression across the operating frequencies. The compact design enables easy integration into flexible RF coil arrays. Furthermore, this study explores the potential for dual-tuned applications and alternative topologies, highlighting the versatility of the LCCC balun in advanced MRI RF technologies.ConclusionThe LCCC lumped-element balun offers a simple, compact, and versatile solution for flexible MRI RF coils. Its small footprint and strong performance make it a promising candidate for next-generation high-density and dual-tuned RF coil arrays.

Magnetic resonance imaging (MRI) scanning remains largely restricted to specific modalities, typically involving low radiofrequency (RF) power levels and stringent protocols for patients with deep brain stimulation (DBS) implants, due to safety concerns related to RF-induced heating of the implants. A 6-channel dual-role head coil array capable of modulating the electric-field (E-field) distribution was designed and evaluated using electromagnetic (EM) simulations. By optimizing the resonant frequency of each coil element during RF transmission, the transmit field was reshaped, leading to a significant reduction in RF-induced heating near the DBS lead tip. The proposed method was validated across two scenarios of increasing complexity: 1) a simple straight conductive wire for concept validation and 2) four realistic DBS leads representing complex real-world scenarios. The coil settings can be optimized either to suppress the E-field at a specific location, such as the DBS lead tip, or to suppress the peak specific absorption rate (SAR) across the entire human head. For location-specific E-field suppression, the simplified predefined-state control scheme and the fine-tuning genetic algorithm (GA)-based framework were implemented, achieving E-field reductions of 45.9% and 68.3%, respectively. For whole-head peak SAR suppression, the annealed Log-Sum-Exp (LSE)-Adaptive Moment Estimation (Adam) framework (LSE-Adam) was implemented, achieving an average 1 g SAR reduction of 72.09% across four realistic DBS lead models. The dual-role coil demonstrated a high degree of flexibility in controlling the transmit field and reducing RF-induced heating at DBS implants, offering a novel approach to mitigate RF-induced heating of the implants in MRI.

A cascade of biological responses to spinal cord injury (SCI), including neuroinflammation, plays a pivotal role in determining long-term outcomes and has become a primary therapeutic target. Riluzole, a neuroprotective agent, has demonstrated efficacy in preserving tissue integrity and improving motor function following SCI. The study aims to use this established treatment to verify that resting-state fMRI (rsfMRI) functional connectivity (rsFC) and TSPO PET metrics are reliable biomarkers of SCI severity, progression, and treatment response. 16 male rats with a moderate lumbar contusion injury were administered Riluzole or HBC vehicle. rsfMRI and TSPO PET scans were collected post-SCI alongside motor-sensory behavioral tests. After SCI, significantly stronger rsFC between dorsal-to-dorsal gray matter horns rostral to the SCI was observed in the riluzole group, compared to the vehicle group. A majority of horn pairs rostral and caudal to injury exhibited significant decrease in rsFC over time for both groups and correlated with post-injury behavioral deficits and recovery. TSPO-PET detected increased SCI neuroinflammatory activity. Our results demonstrate reductions in rsFC disruption, validating the role of rsFC as biomarkers of SCI severity and progression. The imaging biomarkers can be used to evaluate the responsiveness to treatment and efficacy of novel therapies in preclinical studies.

Stretchable RF coils offer the potential to improve MRI performance by conforming closely to patient anatomy, regardless of patient size, thereby enhancing both signal-to-noise ratio (SNR) and patient comfort. In this work, we investigate a stretchable receive array design based on the coaxial capacitor (COCA) coil for 7 T MRI, constructed primarily from ultra-flexible Litz wire stitched onto elastic fabric substrates. The COCA coil eliminates the need for lumped capacitors and maintains stable decoupling performance under transverse stretching, provided that the overlapped area and the coil area change proportionally as the coil is stretched. Bench tests and phantom imaging experiments demonstrate that elliptical COCA coils (in the non-stretched state) maintain consistent decoupling characteristics across stretch ratios up to ×1.3 and outperform fixed arrays in SNR across varying phantom sizes. The proposed design shows strong potential for integration into wearable coil arrays, enabling improved imaging quality and adaptability for diverse patient anatomies.

PURPOSE:To develop a wearable wireless resonator glasses design that enhances eye MRI signal-to-noise ratio (SNR) without compromising whole-brain image quality at 7 T. METHODS:The device integrates two detunable LC loop resonators into a lightweight, 3D-printed frame positioned near the eyes. The resonators passively couple to a standard 2Tx/32Rx head coil without hardware modifications. Bench tests assessed tuning, isolation, and detuning performance. B1 + maps were measured in a head/shoulder phantom, and SNR maps were obtained in both phantom and in vivo experiments. RESULTS:Bench measurements confirmed accurate tuning, strong inter-element isolation, and effective passive detuning. Phantom B1 + mapping showed negligible differences between configurations with and without the resonators. Phantom and in vivo imaging demonstrated up to a ∼3-fold SNR gain in the eye region, with no measurable SNR loss in the brain. CONCLUSION:The wireless resonator glasses provide a low-cost, easy-to-use solution that improves ocular SNR while preserving whole-brain image quality, enabling both dedicated eye MRI and simultaneous eye-brain imaging at ultrahigh field.

PURPOSE:Inductively coupled coils enhance local MRI sensitivity, yet strong coupling with nearby primary coils typically causes resonance splitting and impedance mismatch, which are traditionally considered detrimental. This work investigates why inductively coupled coils can still function effectively even in the presence of severe coupling and clarifies the role of modern receive preamplifiers in mitigating coupling effects. METHODS:Bench experiments were performed using primary coils (10 and 15 cm) and secondary inductively coupled coils (3-9 cm) tuned to the same Larmor frequency at 1.5, 3, and 7 T. Resonance characteristics and primary-coil impedance variations were evaluated under open-circuit, 50-Ω, and low-input-impedance preamplifier terminations. MRI validation was conducted at 7 T without retuning the primary coil after introducing a closely positioned, inductively coupled coil, while intentionally varying preamplifier decoupling conditions. RESULTS:Open-circuit and 50-Ω terminations produced pronounced resonance splitting and significant impedance distortion. In contrast, low-input-impedance preamplifier termination preserved the inductively coupled coil resonance despite strong coupling. Although the primary-coil impedance shifted substantially, it remained within acceptable noise-figure contours, resulting in negligible SNR penalty. Degraded preamplifier decoupling led to a 21%-23% SNR reduction. CONCLUSION:Modern preamplifiers fundamentally alter coupled-coil behavior, enabling inductively coupled coils to operate near primary coils without significant SNR degradation and simplifying inductively coupled coil design.

Introduction and Objectives:High-resolution functional magnetic resonance imaging (fMRI) allows the mapping of functional organization of intraspinal circuits. This study aimed to identify nociceptive heat processing regions within the gray matter of the lumbar spinal cords and delineate their functional organization using task and resting-state fMRI in rats under anesthesia. Methods:High-resolution fMRI BOLD data were acquired from L3-L5 spinal segments during noxious heat (47.5°C) stimulation of the left hind paw and at rest at 9.4T MRI. Results:Noxious heat-elicited BOLD signal increases were detected at deep layers of dorsal horns and intermediate zone within the rostral lumbar enlargement (L3) and deep layers of the ipsilateral dorsal horn in lumbar segment L4. Resting-state functional connectivity (rsFC) analysis revealed the strongest rsFC strengths between dorsal-dorsal and ventral-ventral horns within each lumbar segment. No significant rsFC was found between the horns in different segments. Conclusion:Our results demonstrate that lumbar enlargement (L3 and L4) was involved in processing heat nociceptive information and bilateral dorsal and ventral horns were strongly interconnected at rest. We hypothesize that the intermediate zone in the rostral subsegment of L3 serves as a modulation center for nociceptive processing within the lumbar cord.

The progression and repair of a traumatically injured spinal cord (SCI) involves multifactored processes. Noninvasive, mechanism-informative objective biomarkers could greatly facilitate the translation of findings from preclinical animal models to patient applications. We aimed to develop and validate multiparametric chemical exchange saturation transfer (CEST) and quantitative magnetization transfer (qMT) magnetic resonance imaging (MRI) biomarkers for assessing SCI severity, demyelination, and neuroinflammation, as well as the response to neuroprotective drug treatment riluzole. Changes in CEST and qMT MRI metrics before and after a moderate contusion injury at the L1 level of the lumbar spinal cord were compared between two groups of rats that received either the riluzole or a vehicle treatment over 8 weeks. The specificity of these MRI biomarkers was validated by postmortem immunohistology. The functional relevance of these biomarkers was evaluated by correlation with hindlimb sensorimotor and pain behavior. The pool size ratio (PSR) maps from qMT acquisitions of the SCI region in riluzole-treated rats showed increased white matter macromolecular content compared to the HBC vehicle-treated group, suggesting increased myelin levels and possible remyelination of the injured spinal cord. CEST APT pool (3.5 ppm) amplitude decreased at the region rostral to the injury in riluzole-treated rats compared to the vehicle group, indicating potentially reduced neuroinflammatory activity. MRI metrics correlated temporally with behavioral measures of injury severity and recovery. Histological analysis spatially validated MRI-revealed myelination and neuroinflammation status and confirmed differences between the drug and vehicle treatment groups. Quantitative MRI is well suited for monitoring and quantifying the efficacy of pharmacological treatments in preclinical spinal cord injury models. Multiparametric MRI changes in white matter myelination (qMT PSR) and neuroinflammation (CEST APT) in the injured spinal cord were related to injury severity, behavioral deficits, and recovery progression over time. Both imaging metrics captured enhanced recovery from the neuroprotective drug riluzole, supporting the practical utility of these MRI biomarkers.

PURPOSE:To compare two identically sized wireless resonator designs, one with strongly coupled units and the other with decoupled units, for their ability to enhance receive performance in MRI when used with local receive arrays. METHODS:Both wireless resonator designs were fabricated and experimentally evaluated for detuning efficiency, SNR improvements, and parallel imaging performance (g-factor) at 1.5 T. They were used alongside a 12-channel head receive array, with the standard body coil serving as the RF transmitter. RESULTS:Experimental data showed that the wireless resonator with decoupled units consistently outperformed that with coupled units, with up to threefold improvement in SNR and a reduction of maximum/average g-factor from 4.6/1.8 to 3.1/1.3. Notably, compared to the original receive array (maximum/average: 3.9/1.7), the decoupled design further improved the g-factor, highlighting superior performance in accelerated imaging. CONCLUSION:Wireless resonators with decoupled units offer significant advantages in improving MRI image quality and parallel imaging performance over their coupled counterparts. Their ease of detuning and pronounced gains in SNR and g-factor make them a compelling choice for wireless resonator designs.

This study investigated the efficacy of using wireless resonator inserts in conjunction with head and neck coils to enhance carotid artery imaging. A group of patients diagnosed with carotid plaque underwent MRI scans using a Siemens head and neck coil and wireless resonator insert. The results showed significant improvements in image quality, resolution and atherosclerotic plaque detection capabilities compared to traditional wired connections. The wireless setup minimizes interference and artifacts during imaging, promoting smoother, more reliable scanning. These findings highlight the potential of wireless coil technology to advance MRI imaging and improve clinical diagnosis and treatment of carotid artery-related diseases. Further research and optimization of the imaging protocol is required to maximize the benefits of this innovative approach.

BACKGROUND AND OBJECTIVES:Current guidelines recommend contrast-enhanced CT/MRI as confirmatory imaging tests for diagnosing hepatocellular carcinoma (HCC). However, these modalities are not always able to differentiate HCC from benign/dysplastic nodules that are commonly observed in cirrhotic livers. Consequently, many lesions require either pathological confirmation via invasive biopsy or surveillance imaging after 3-6 months, which results in delayed diagnosis and treatment. We aimed to develop noninvasive imaging biomarkers of liver cell size and cellularity, using magnetic resonance imaging (MRI), and to assess their utility in identifying HCC. METHODS:MR cytometry combines measurements of water diffusion rates over different times corresponding to probing cellular microstructure at different spatial scales. Maps of microstructural properties, such as cell size and cellularity, are derived by fitting voxel values in multiple diffusion-weighted images to a three-compartment (blood, intra-, and extracellular water) model of the MRI signal. This method was validated in two phases: (1) histology-driven simulations, utilizing segmented histological images of different liver pathologies, and (2) ex vivo MR cytometry performed on fixed human liver specimens. RESULTS:Both simulations and ex vivo MR cytometry of fixed human liver specimens demonstrated that HCC exhibits significantly smaller cell sizes and higher cellularities compared to normal liver and cirrhotic regenerative nodules. CONCLUSION:This study highlights the potential of MR cytometry to differentiate HCC from non-HCC lesions by quantifying cell size and cellularity in liver tissues. Our findings provide a strong foundation for further research into the role of MR cytometry in the noninvasive early diagnosis of HCC.

The current diagnostic gold standard for metabolic dysfunction-associated steatohepatitis (MASH) requires invasive biopsy to assess steatosis, inflammation, and ballooning. While MRI-based proton density fat fraction (PDFF) and MR elastography address steatosis and fibrosis, non-invasive methods for evaluating hepatic inflammation remain lacking. This study developed a diffusion MRI (dMRI)-based MR cytometry technique to map liver cellular properties, including MRI-derived cell size (excluding fat content) and cell density. Validation through histology-driven simulations and ex vivo MRI of fixed human liver specimens demonstrated that stromal regions exhibit smaller MRI-derived cell sizes and higher cell densities than both normal and fatty tissues. An in vivo feasibility study, conducted on healthy subjects (n = 5) and MASH patients (n = 5) using a clinical 3 T MRI system, further showcased the potential of MR cytometry to characterize pathological changes in liver microstructure.

Flexible RF coils enhance patient comfort and increase filling factors, making them attractive for MRI. However, achieving first-mode resonance at 7 T for large-diameter, flexible coils remains a challenge. We present a coaxial capacitor (COCA) coil, which can be 10 cm in diameter and still operates in the first resonant mode at 298 MHz. Unlike coaxial cable coils that rely on self-resonance, the COCA coil combines ultrasoft Litz wire for inductance with a short coaxial structure for capacitance. Bench tests showed that a 1-capacitor COCA coil provides comparable tuning/matching robustness, effective detuning, and inter-element decoupling performance to conventional rigid coils with three distributed lumped capacitors. MRI acquisitions demonstrated high SNR, especially when the coil conformed to the curvature of the load, with up to 20 % SNR improvement over flat configurations. The coil's ability to retain tuning and matching across different shapes also supports the development of shape-adjustable arrays. By enabling flexible, large-diameter coils to operate in the first resonant mode at ultrahigh fields, the COCA design offers a promising solution for imaging anatomies with complex geometries, such as the shoulder, foot, and spine.

Background Inductively coupled wireless coils are increasingly used in MRI due to their cost-effectiveness and simplicity, eliminating the need for expensive components like preamplifiers, baluns, coil plugs, and coil ID circuits. Existing tools for predicting component values and electromagnetic (EM) fields are primarily designed for cylindrical volume coils, making them inadequate for irregular volume-type wireless coils. Purpose The aim of this study is to introduce and validate a novel magnetic (H-) field probe-based co-simulation method to accurately predict capacitance values and EM fields for irregular volume-type wireless coils, thereby addressing the limitations of current prediction tools. Methods The proposed method involves several key steps: modeling the coil in EM simulation software, replacing lumped components with 50-Ω ports, placing well-decoupled double pick-up sniffer probes within the wireless coil, conducting full-wave EM simulations, and exporting the S-parameter matrix to an RF circuit simulation tool for optimization. The RF circuit simulation optimizes component values by maximizing the average magnitude of the root square of Sxys (mean_√Sxy) of double probes and minimizing the normalized standard deviation of √Sxy (normStd_√Sxy). The optimized capacitance values are validated through re-performing EM simulations, and hardware prototypes are fabricated and tested in MRI experiments. Results The method was validated using bottle-shaped and dome-shaped Litzcage coils designed for 1.5 T MRI. Consistent resonant peaks and magnetic field distributions were observed across different coil designs. The optimized capacitance values obtained from circuit-level simulations were confirmed through EM simulations. Significant SNR enhancements were observed in MRI experiments, with the wireless hand and wrist/head coil showing an overall SNR enhancement of 12.8/3.4-fold in EM simulation and 13.4/3.8-fold in MRI experiments, compared to the body coil alone. Conclusions The H-field probe-based co-simulation method provides an efficient and accurate solution for designing and optimizing irregular wireless RF coils in MRI. By integrating EM simulation, H-field probes, and RF circuit optimization, this method reduces the need for extensive full-wave EM simulations and accurately predicts capacitance values and EM fields. The validation using irregular Litzcage coils demonstrated the method's efficacy, contributing to improved imaging quality in MRI applications. This approach offers a valuable tool for coil developers and researchers, facilitating the development of high-quality irregular wireless coils for enhanced MRI performance.

Ultrahigh field (UHF) Magnetic Resonance Imaging (MRI) offers an elevated signal-to-noise ratio (SNR), enabling exceptionally high spatial resolution that benefits both clinical diagnostics and advanced research. However, the jump to higher fields introduces complications, particularly transmit radiofrequency (RF) field (B+1 ) inhomogeneities, manifesting as uneven flip angles and image intensity irregularities. These artifacts can degrade image quality and impede broader clinical adoption. Traditional RF shimming methods, such as Magnitude Least Squares (MLS) optimization, effectively mitigate B+1 inhomogeneity, but remain time-consuming. Recent machine learning approaches, including RF Shim Prediction by Iteratively Projected Ridge Regression and other deep learning architectures, suggest alternative pathways. Although these approaches show promise, challenges such as extensive training periods, limited network complexity, and practical data requirements persist. In this paper, we introduce a holistic learning-based framework called Fast-RF-Shimming, which achieves a 5000 x speed-up compared to the traditional MLS method. In the initial phase, we employ random-initialized Adaptive Moment Estimation (Adam) to derive the desired reference shimming weights from multi-channel B+1 fields. Next, we train a Residual Network (ResNet) to map B+1 fields directly to the ultimate RF shimming outputs, incorporating the confidence parameter into its loss function. Finally, we design Non-uniformity Field Detector (NFD), an optional post-processing step, to ensure the extreme non-uniform outcomes are identified. Comparative evaluations with standard MLS optimization underscore notable gains in both processing speed and predictive accuracy, which indicates that our technique shows a promising solution for addressing persistent inhomogeneity challenges.

Purpose: Static field (B-0) inhomogeneities present a major challenge in high-field MRI. Multicoil shimming using independent, local, direct-current (DC) shim coils has emerged as a powerful and flexible technique to address this issue. However, many-turn DC coils can lead to significant mutual coupling with radiofrequency (RF) coils, causing transmit field (B-1(+)) distortions and signal-to-noise ratio degradation. Methods: We introduce an innovative RF-transparent DC coil that performs B-0 shimming while minimizing RF performance impact. The design incorporates float traps to maintain high RF impedance, allowing flexible placement relative to the RF coil without compromising signal-to-noise ratio or affecting B-1(+). We fabricated square-shaped DC coils with float traps for 3T MRI and compared them with conventional DC coils. To demonstrate high Delta B-0/Amp efficiency, we conducted a B-0 shimming experiment around a metal hip implant. Results: Bench tests and MRI experimental results demonstrated that the RF-transparent DC coil effectively minimized RF interference, preserved signal-to-noise ratio, and maintained B-1(+), even when placed near the RF receive coil. Additionally, the DC coil significantly improved B0 homogeneity near metal implants and substantially reduced image distortion. Conclusion: The RF-transparent DC coil offers a flexible, effective solution for managing B-0 inhomogeneities, paving the way for integrating multiturn DC coils in clinical MRI settings without extensive hardware modifications.

BACKGROUND:Magnetic resonance imaging (MRI) is a non-invasive technique that produces high-resolution images with excellent soft-tissue contrast, crucial for diagnosing various medical conditions. A key factor in MRI quality is the signal-to-noise ratio (SNR), which directly affects image clarity. To enhance SNR, passive inserts like high-permittivity dielectric pads or metamaterials are used between the tissue and coil. However, this method faces challenges such as detuning during radiofrequency (RF) transmission, which can interfere with the transmit field (B1 +) and pose safety issues. PURPOSE:This study proposes a novel method to enhance SNR in MRI by using a non-closed lumped-element ladder resonator as a wireless insert. The aim is to optimize this ladder resonator through simulations and validate its performance in both phantom and in vivo MRI experiments. METHODS:The ladder resonator was designed and optimized through electromagnetic (EM) and RF circuit simulations using Ansys HFSS software. Various configurations (4, 6, 8, and 10 rungs) were tested. The optimized 8-rung resonator was then fabricated and evaluated against a single-loop resonator of the same size. MRI experiments were conducted using a 1.5T Siemens MRI scanner, assessing SNR improvements in both phantoms and volunteers. RESULTS:Simulation results indicated that the ladder resonator significantly improved local SNR compared to the single-loop resonator. The 8-rung ladder resonator provided the best performance. Experimental results corroborated these findings, with the 8-rung ladder resonator showing SNR improvements up to 4.7 times in human head images, compared to the standard head array alone. CONCLUSIONS:The study demonstrates that wireless ladder resonators can significantly enhance SNR in MRI, offering superior performance and more uniform sensitivity compared to traditional single-loop designs. The detunable feature of the ladder resonator ensures it does not interfere with the RF field, making it suitable for routine clinical use. The simplicity, cost-effectiveness, and compatibility with various MRI platforms underscore its potential for widespread clinical adoption.

Accurate and individualized human head models are becoming increasingly important for electromagnetic (EM) simulations. These simulations depend on precise anatomical representations to realistically model electric and magnetic field distributions, particularly when evaluating Specific Absorption Rate (SAR) within safety guidelines. State of the art simulations use the Virtual Population due to limited public resources and the impracticality of manually annotating patient data at scale. This paper introduces Personalized Head-based Automatic Simulation for EM properties (PHASE), an automated open-source toolbox that generates high-resolution, patient-specific head models for EM simulations using paired T1-weighted (T1w) magnetic resonance imaging (MRI) and computed tomography (CT) scans with 14 tissue labels. To evaluate the performance of PHASE models, we conduct semi-automated segmentation and EM simulations on 15 real human patients, serving as the gold standard reference. The PHASE model achieved comparable global SAR and localized SAR averaged over 10 grams of tissue (SAR-10g), demonstrating its potential as a promising tool for generating large-scale human model datasets in the future. The code and models of PHASE toolbox have been made publicly available: https://github.com/hrlblab/PHASE.

Magnetic resonance-guided focused ultrasound (MRgFUS) is a non-invasive and effective alternative to conventional deep-brain stimulation and radio-frequency lesioning for essential tremors and is being investigated for essential tremors, pains, and other applications. During MRgFUS treatment, FUS transducers are typically positioned at the top of the head. To precisely focus the ultrasound force or create a hot spot at the targeted area, adjustments in the transducer position are necessary. Consequently, a sizable opening in the RF coil becomes essential to ensure compatibility with the MRgFUS device. In this study, six coil layouts are simulated, and their performances, including signal-to-noise ratio (SNR) and the g-factor, are evaluated using the DUKE human head model at 3 Tesla. This study aims to contribute to the development of head coil designs tailored for MRgFUS applications.