High Specific Absorption Rate Research Articles

Specific nutrient absorption rates of transplanted cucumber seedlings are highly related to RGR and influenced by grafting method, AMF inoculation and salinity

The objective of this study was to assess the influence of different grafting methods and mycorrhizal inoculation of (salt-stressed) cucumber seedlings regarding plant establishment and nutrient absorption rates. Young cucumber (Cucumis sativus L) plants were grafted onto AMF-free, or AMF inoculated Cucurbita maxima × C. moschata transplants, by two grafting methods; common root intact, splice grafting (SG) and root-pruned splice grafting (RPSG). A similar number of self-rooted cucumber plants were kept as control. The results of this study indicate that the RPSG method offers advantages over the SG method, especially under saline conditions by improving the specific absorption rates (SAR). Improved growth rates of RPSG plants could be related to significantly higher SAR of certain elements such as N, P (under non-saline conditions) and N, Ca, K, Mg and Fe (under salt stress). High SAR of RPSG seedlings are suggested to be largely based on the young adventitious roots established after pruning. The inoculation with AMF enhanced the nutrient uptake and stand establishment rate of cucumber seedlings, especially in salt stressed grafted plants, through extending their root system and enhancing the photosynthetic rate. The study indicates how stand establishment rate and plant nutrition can be enhanced in commercial cucumber production by using cutting grafting (RPSG) and pre transplanting AMF inoculation on favourable grafting combinations.

Enhancement of Carbon Oxides Hydrogenation on Iron‐Based Nanoparticles by In‐Situ Water Removal

AbstractThe carbidization of Fe(0) nanoparticles (NPs) under syngas (CO/H2) produces crystalline Fe2.2C iron carbide NPs (ICNPs) displaying excellent hyperthermia properties, however, this transformation is significantly delayed by the concomitant water formation. Consequently, very long carbidization times (∼140 h) are needed to obtain ICNPs with high specific absorption rate. In this paper, we show that the rate of the carbidization process can be greatly enhanced by the in‐situ removal of water using activated molecular sieves. As a result, ICNPs displaying very high heating power were obtained after only 40 h. Using this strategy, CO was successfully replaced by CO2 as a carbon source in the carbidization process, resulting in the efficient conversion of Fe(0) NPs to ICNPs at relatively low temperature (230 °C). Without water removal, carbidization did not occur under these conditions, and the Fe(0) NPs were clearly oxidized. In addition, this approach was successfully applied to displace the equilibrium of CO2 hydrogenation and accelerate the rate of the magnetically induced hydrogenation of CO2 on ICNPs. Interestingly, the in‐situ water removal had also a strong influence on the product distribution and especially the chain growth process, leading to a higher selectivity towards the formation of C3H8 (∼11 %).

Cube-Shaped Cetyltrimethyl Ammonium Bromide-Coated Nickel Ferrite Nanoparticles for Hyperthermia Applications

Cetyltrimethyl ammonium bromide (CTAB)-coated nickel ferrite (NiFe2O4) nanoparticles were synthesized using the high-temperature thermal decomposition method. The hydrophobic particles became water-soluble after the coating with CTAB, a positively charged ligand. The morphology and the phases of the nanoparticles were characterized using X-ray diffraction and transmission electron microscopy (TEM). TEM images demonstrated that the particles were cube-shaped; the average length of their side was 32.6 nm. Inductively coupled plasma spectroscopy measurements were performed to confirm the chemical composition of the particles. The particles exhibited superparamagnetic behavior with negligible coercive force. Magnetic heating of the aqueous suspensions of nanoparticles was performed in the presence of a radio-frequency magnetic field of 4.4 kA/m at a frequency of 216 kHz. The 1.5-mg/mL sample reached the hyperthermia target temperature of 42 °C and exhibited a high specific absorption rate (SAR) value of 152 W/g. These findings show that the investigated nanoparticles are suitable for magnetic hyperthermia applications and have the advantage of low dosage owing to their high SAR values.

SERIAL transmit – parallel receive (STxPRx) MR imaging produces acceptable proton image uniformity without compromising field of view or SAR guidelines for human neuroimaging at 9.4 Tesla

PurposeNon-uniform B1+ excitation and high specific absorption rates (SAR) compromise proton MR imaging of human brain at 9.4 T (400.5 MHz). By combining a transmit/receive surface coil array using serial transmission of individual coils with a total generalized variation reconstruction of images from all coils, acceptable quality human brain imaging is demonstrated. MethodsB0 is shimmed using sodium MR imaging (105.4 MHz) with a birdcage coil. Proton MR imaging is performed with an excitation/receive array of surface coils. The modified FLASH pulse sequence transmits serially across each coil within the array thereby distributing SAR in time and space. All coils operate in receive mode. Although the excitation profile of each transmit coil is non-uniform, the sensitivity profile estimated from the non-transmit receive coils provides an acceptable sensitivity correction. Signals from all coils are combined in a total generalized variation (TGV) reconstruction to provide a full field of view image at maximum signal to noise (SNR) performance. ResultsHigh-resolution images across the human head are demonstrated with acceptable uniformity and SNR. ConclusionProton MR imaging of the human brain is possible with acceptable uniformity at low SAR at 9.4 Tesla using this serial excitation and parallel reception strategy with TGV reconstruction.

Squeezed Trajectory Design for Peak RF and Integrated RF Power Reduction in Parallel Transmission MRI.

High peak RF amplitude and excessive specific absorption rate (SAR) are two critical concerns for hardware implementation and patient safety in scientific and clinical research for high field MRI using parallel transmissions (pTX). In this paper, we introduce a squeezing strategy to reduce peak RF amplitude and integrated RF power via direct reshaping of the k-space trajectory. In the existing peak RF / integrated RF power optimization methods gradient amplitude or slew rate is reduced, but the k-space trajectory remains unchanged. Unlike these traditional methods, we worked directly in the excitation k-space to reshape k-space traversal by a squeezing vector in order to achieve peak RF and total RF power optimization, using a particle swarm optimization algorithm. The squeezing strategy was applied to the conventional variable density spiral (CVDS) and the variable rate selective excitation (VERSE) trajectories, dubbed SVDS (squeezed variable density spiral) and SVERSE (squeezing trajectory with VERSE), respectively, for different excitation profiles of small or large tip angles. Pulse acceleration and off-resonance effects were evaluated for an 8-ch pTX via Bloch simulation. CVDS, VERSE, SVDS, and SVERSE pulses were implemented on a 3T scanner with a 2-ch pTX. Phantom and in vivo experiments were performed for reduced FOV (rFOV) imaging. The results show that SVDS pulses simultaneously reduce integrated RF power and peak RF by about 30% on average compared to CVDS pulses for a square pattern ( $80\times80$ mm2) with flip angles of 30°, 90°, and 180°. Compared with the VERSE method under the same peak RF constraints, the SVDS method reduces integrated RF power by an average of 20% for small tip excitations for profiles of slice, rectangular, square, and circle, and has slightly reduced excitation accuracy slightly (about 0.6%, from 6.8% to 7.4%). The SVERSE method shortens the duration of the VERSE pulse by 12.8% at large ti p angle (180°). Feasibility for rFOV imaging was demonstrated with phantom and in vivo experiments with squeezed pulses.

A 2D spiral turbo-spin-echo technique.

2D turbo-spin-echo (TSE) is widely used in the clinic for neuroimaging. However, the long refocusing radiofrequency pulse train leads to high specific absorption rate (SAR) and alters the contrast compared to conventional spin-echo. The purpose of this work is to develop a robust 2D spiral TSE technique for fast T2 -weighted imaging with low SAR and improved contrast. A spiral-in/out readout is incorporated into 2D TSE to fully take advantage of the acquisition efficiency of spiral sampling while avoiding potential off-resonance-related artifacts compared to a typical spiral-out readout. A double encoding strategy and a signal demodulation method are proposed to mitigate the artifacts because of the T2 -decay-induced signal variation. An adapted prescan phase correction as well as a concomitant phase compensation technique are implemented to minimize the phase errors. Phantom data demonstrate the efficacy of the proposed double encoding/signal demodulation, as well as the prescan phase correction and concomitant phase compensation. Volunteer data show that the proposed 2D spiral TSE achieves fast scan speed with high SNR, low SAR, and improved contrast compared to conventional Cartesian TSE. A robust 2D spiral TSE technique is feasible and provides a potential alternative to conventional 2D Cartesian TSE for T2 -weighted neuroimaging.

The human skin as a sub-THz receiver – Does 5G pose a danger to it or not?

In the interaction of microwave radiation and human beings, the skin is traditionally considered as just an absorbing sponge stratum filled with water. In previous works, we showed that this view is flawed when we demonstrated that the coiled portion of the sweat duct in upper skin layer is regarded as a helical antenna in the sub-THz band. Experimentally we showed that the reflectance of the human skin in the sub-THz region depends on the intensity of perspiration, i.e. sweat duct's conductivity, and correlates with levels of human stress (physical, mental and emotional). Later on, we detected circular dichroism in the reflectance from the skin, a signature of the axial mode of a helical antenna. The full ramifications of what these findings represent in the human condition are still unclear. We also revealed correlation of electrocardiography (ECG) parameters to the sub-THz reflection coefficient of human skin. In a recent work, we developed a unique simulation tool of human skin, taking into account the skin multi-layer structure together with the helical segment of the sweat duct embedded in it. The presence of the sweat duct led to a high specific absorption rate (SAR) of the skin in extremely high frequency band. In this paper, we summarize the physical evidence for this phenomenon and consider its implication for the future exploitation of the electromagnetic spectrum by wireless communication. Starting from July 2016 the US Federal Communications Commission (FCC) has adopted new rules for wireless broadband operations above 24 GHz (5 G). This trend of exploitation is predicted to expand to higher frequencies in the sub-THz region. One must consider the implications of human immersion in the electromagnetic noise, caused by devices working at the very same frequencies as those, to which the sweat duct (as a helical antenna) is most attuned. We are raising a warning flag against the unrestricted use of sub-THz technologies for communication, before the possible consequences for public health are explored.

A comparative study of direct absorption nanofluids for solar thermal applications

Direct absorption nanofluid has been introduced as an effective alternative to increase solar thermal conversion efficiency. Hybrid nanofluids were also recently proposed to broaden the absorption spectrum. However, a comparative assessment of the performance of commonly used nanomaterials for solar energy harness is still lacking. In this study, a well-controlled experiment was performed using three different categorised nanofluids, i.e., gold, copper, carbon black nanofluids and their hybrids, to assess their performance in terms of photothermal conversion efficiency (PTE), specific absorption rate (SAR) and materials cost. A mathematical model was built based on the Beer’s law to predict the PTE enhancement. The results revealed, contrary to previously reported, the PTE was not increased by blending different nanofluids with different absorbance peaks, which is mainly due to the dilution of nanoparticles’ concentration. Furthermore, it is found that although gold nanofluids have high SAR, their expensive cost limits their practical use, whereas carbon black nanofluids are more feasible. In addition it was found that the theoretical PTE can be well predicted mathematically based on the optical properties of the used nanofluids.

Highly Efficient Wearable CPW Antenna Enabled by EBG-FSS Structure for Medical Body Area Network Applications

A wearable fabric CPW antenna is presented for medical body area network (MBAN) applications at 2.4 GHz based on an electromagnetic bandgap design and frequency selective surface (EBG-FSS). Without EBG-FSS, the basic antenna has an omnidirectional radiation pattern, and when operated close to human tissue, the performance and efficiency degrade, and there is a high specific absorption rate. To overcome this problem, the antenna incorporates EBG-FSS, which reduces the backward radiation, with SAR reduced by 95%. The gain is improved to 6.55 dBi and the front-to-back ratio is enhanced by 13 dB compared to the basic antenna. The overall dimensions of the integrated design are $60\times 60\times2.4$ mm3. Simulation and experimental studies reveal that the antenna integrated with EBG-FSS can tolerate loading by human tissue as well as bending. Thus, the design is a good candidate for MBAN applications.

A z-gradient array for simultaneous multi-slice excitation with a single-band RF pulse.

Multi-slice radiofrequency (RF) pulses have higher specific absorption rates, more peak RF power, and longer pulse durations than single-slice RF pulses. Gradient field design techniques using a z-gradient array are investigated for exciting multiple slices with a single-band RF pulse. Two different field design methods are formulated to solve for the required current values of the gradient array elements for the given slice locations. The method requirements are specified, optimization problems are formulated for the minimum current norm and an analytical solution is provided. A 9-channel z-gradient coil array driven by independent, custom-designed gradient amplifiers is used to validate the theory. Performance measures such as normalized slice thickness error, gradient strength per unit norm current, power dissipation, and maximum amplitude of the magnetic field are provided for various slice locations and numbers of slices. Two and 3 slices are excited by a single-band RF pulse in simulations and phantom experiments. The possibility of multi-slice excitation with a single-band RF pulse using a z-gradient array is validated in simulations and phantom experiments. Magn Reson Med 80:400-412, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Effect of orientational ordering of magnetic nanoemulsions immobilized in agar gel on magnetic hyperthermia

Magnetic nanoemulsions of droplet size ∼200 nm, loaded with single domain superparamagnetic nanoparticles (MNP), are potential candidates for multimodal hyperthermia due to availability of large loading volume and enhanced permeation and retention (EPR) in the cancerous tissues. In such nanoemulsions, radio frequency alternating magnetic field induced heating occur at two entirely different length scales, viz. Neel-Brown relaxation of the dispersed MNP and Brownian relaxation of emulsion droplets. Here we study the effects of orientation ordering or texturing of droplets, immobilized in a tissue mimicking agar matrix, on the field induced heating efficiency. A higher specific absorption rate (maximum ∼73 ± 2 W/gFe) is observed for droplets orientated parallel to the direction of the alternating magnetic field because of the enhancement of effective uniaxial anisotropy energy density and increased effective relaxation time. For identical and non-interacting MNP oriented parallel to the external DC magnetic field, a threefold increase in the effective uniaxial anisotropy energy density and ∼20–30% increased specific absorption rate are observed as compared to those oriented perpendicular to the magnetic field. Magnetic force microscopy images showed that the spherical morphology of the droplets remains intact even after orientational ordering and average topographic height of the droplets are found to be ∼220 (±17) nm, which is in good agreement with the most probable size obtained from dynamic light scattering. The residual volume magnetization of the emulsion droplets is found to be 1.1 × 10−6 emu/cc, indicating the superparamagnetic nature of the droplets in tissue equivalent environment. The observed increase in heating efficiency of the immobilized and oriented emulsion droplets shows promising applications in multimodal hyperthermia therapy because of the requirement of lower dose of MNP and shorter treatment time.

Fluorescent magnetic nanoparticles as minimally-invasive multi-functional theranostic platform for fluorescence imaging, MRI and magnetic hyperthermia

Designing multifunctional nanomaterials for minimally-invasive biomedical imaging and therapy is an emerging area that integrates imaging and therapy modalities into single functional platform. In this study, we fabricated a multi-functional theranostic platform comprising of (MnxFe1-x)Fe2O4/SiO2 (MFO/SiO2) nanoparticles and fluorescein isothiocyanate. The high saturation magnetization and magnetic susceptibility of MFO/SiO2 provides high relaxivity and specific absorption rate (SAR), which are favorable for high performance MRI and magnetic hyperthermia. The fluorescence signal from the NIH/3T3 cells labeled with the PEGylated fluorescent MFO/SiO2 nanoparticles suggests these nanoparticles passed the cell membrane. The low cytotoxicity, high colloidal stability and the multiple functions demonstrated by our theranostic platform proved its usefulness for multi-purpose biomedical applications.

Hydroxyapatite- M-type strontium hexaferrite: A new composite for hyperthermia applications

Although, the ideal hard ferromagnetic particles are much better energy absorbers as against the ideal superparamagnetic particles, the use of hard ferromagnetic materials in hyperthermia applications has always been a major challenge for researchers due to their high anisotropy. This work introduces a route to use a hard magnetic material (SrFe12O19) in the form of nanoparticle and scaffold in hyperthermia application. Single domain SrFe12O19 nanoparticles, with a hard magnetic behavior, when composited with hydroxyapatite (HA), allowed the use of the minimum frequency and amplitude of the alternative magnetic (AC) field to have high amount of specific absorption rate. This was the outstanding advantages of this work, especially when a monodispersed HA-SrFe12O19 nanocomposite was used. HA-10 wt%SrFe12O19 scaffolds, after gelatin coting, showed a high stable compressive strength with a high uniform interconnected porosities. Besides, HA-10 wt%SrFe12O19 composite nanoparticles showed a high specific absorption rate in both mono and multi dispersed states.

Magnetic and magnetothermal studies of pure and doped gadolinium silicide nanoparticles for self-controlled hyperthermia applications

We report on magnetic and magnetothermal properties of undoped and doped gadolinium silicide (Gd5Si4) nanoparticles with the objective of simultaneously attaining high specific absorption rate (SAR) and low Curie temperature (TC) suitable for self-controlled hyperthermia applications for which TC∼315–320K. Pellets of doped gadolinium silicide Gd5(Si1−xGex)4 and (Gd1−xRx)5Si4 with R=Ho, Nd and Er and 0≤x≤0.35 were made by arc melting and reduced to nanoparticulate form by surfactant assisted ball milling. Structural and morphological studies were done using X-ray diffraction and scanning electron microscopy respectively. All samples show soft magnetic properties. At low fields there is a ferromagnetic to paramagnetic transition that reduces remanance and coercivity to zero making these materials very attractive for biomedical applications. Zero-field-cooled thermal demagnetization measurements showed that TC of these nanoparticles can be lowered to lie within the limits required for self-controlled hyperthermia by varying the dopant concentration. Specific absorption rates (SAR’s) were obtained from magnetothermia measurements made in an ac magnetic field of amplitude 10Oe and frequency 300kHz. We have identified samples that have SAR values larger or comparable to those of magnetite and several ferrite nanoparticles, while having Curie temperatures that are low enough for self controlled hyperthermia applications.

Magnetic heating of triethylene glycol (TREG)-coated zinc-doped nickel ferrite nanoparticles

Triethylene glycol (TREG)-coated nickel-zinc (Ni-Zn) ferrite nanoparticles were synthesized via the hydrothermal method and characterized for application to magnetic hyperthermia. Ni-Zn ferrite particles of Ni1−xZnxFe2O4 with three different zinc contents of x=0.2, 0.4, and 0.6 were formulated to investigate the structural and magnetic properties according to the zinc content. Transmission electron microscopy images revealed that the particles were spherical in shape and that the average diameters of the particles were 10.67, 13.02, and 18.73nm for zinc contents of 0.6, 0.4, and 0.2, respectively. Fourier transform infrared spectroscopy confirmed that the TREG was firmly coated on the surface of the particles. The saturation magnetization decreased with the increasing zinc content in the particles, which affected the heating ability of the particles in the alternating magnetic field. The heating ability of the Ni0.8Zn0.2Fe2O4 and Ni0.6Zn0.4Fe2O4 particles facilitated the aqueous solution of these particles to reach the target temperature of 42°C for magnetic hyperthermia, while an aqueous solution of Ni0.2Zn0.8Fe2O4 particles with a high particle concentration did not reach the target temperature. The high specific absorption rates of the Ni0.8Zn0.2Fe2O4 and Ni0.6Zn0.4Fe2O4 particles indicate that these particles are applicable to magnetic hyperthermia.

Synthesis and Characterization of Bi-Magnetic Core/Shell Nanoparticles for Hyperthermia Applications

Magnetic nanoparticles, which exhibit a high specific absorption rate (SAR), have drawn a great deal of interest for hyperthermia. Bi-magnetic CS-MNPs of Zn x Co1– x Fe2O4@MnFe2O4 with $x$ ranging between 0 and 0.8 have been synthesized by seed-mediated growth. Structural morphology and magnetic properties have been studied. This paper presents the effects of substitution of Zn2+ on the structural and magnetic properties of Zn x Co1– x Fe2O4@MnFe2O4 nanoparticles. The structure and morphology of the CS-MNPs was established by using X-ray diffraction (XRD), transmission electron microscopy (TEM), and dark field TEM (DF-TEM). XRD patterns confirm the existence of a single-phase cubic spinel crystal structure. The average particle size has been estimated from the statistical analysis of the TEM images. DF-TEM results confirmed the formation of CS-MNPs. Vibrating sample magnetometery demonstrated an increase in saturation magnetization with an increasing Zn concentration up to $x = 0.4$ and a decrease thereafter. High heating efficacy of CS-MNPs may extend hyperthermia therapy to deeper tumors. The experimental results showed that CS-MNPs have a higher SAR than the core ones. These nanoparticles are coupled-exchange between soft and hard magnetic phases.

Enhancing the Magnetic Heating Capacity of Iron Oxide Nanoparticles through Their Postproduction Incorporation into Iron Oxide–Gold Nanocomposites

Small variations in the synthesis conditions of iron oxide–gold nanocomposites, made in an aqueous medium by a coprecipitation reaction, have a significant effect on the magnetic‐heating properties of the iron oxide nanoparticles. Citric acid coated magnetite/maghemite (Fe3O4/γ‐Fe2O3) nanoparticles were used as a Turkevich‐style reducing agent and added to varying concentrations of HAuCl4 to form iron oxide–gold nanoparticle composites with Fe/Au molar ratios ranging from ca. 5:1 to ca. 300:1. The magnetic‐heating capacities of the products were measured in a high‐frequency alternating field (peak amplitude 6.6 kA/m, frequency 967 kHz), to determine both the specific absorption rates (SARs) and the intrinsic loss powers (ILPs) of the products. The iron oxide (FeOx) precursor presented a moderately high SAR of 33.9 W/gFeOx and an ILP of 0.8 nH m2/kgFeOx, but the iron oxide–gold nanocomposite formed with 0.75 mm HAuCl4 had an almost threefold‐enhanced heating capacity with a SAR of 88.3 W/gFeOx and an ILP of 2.1 nH m2/kgFeOx. This corresponds to an ILP of 3.0 nH m2/kgFe, which is as high as that of any commercially available material to date. This result has implications for the possible postproduction enhancement of the magnetic‐heating capacities of similar iron oxide systems as well as increasing the theranostic potential of such materials through the incorporation of Au nanoparticles, which may act as integrated binding sites for drugs or other beneficial biomolecules.

Microwave assisted extraction of polyphenols using a coaxial antenna and a cooling system

Microwave assisted extraction is a powerful tool for natural compounds extraction from plants. The main goal of our research is to obtain a maximum extraction yield without affecting the chemical structure of the valuable natural compounds. In order to avoid the degradation of the latter, a special equipment has been developed. This equipment allows microwave heating using a slot end coaxial antenna into a microwave applicator provided with an efficient cooling system. Consequently, a high specific absorption rate (SAR) is achieved at low temperatures. A slightly non-uniform heating was observed at lower stirring rates that represents an advantage for the extraction process, keeping the extracted product without any degradation. Using this equipment, polyphenols were extracted from sea buckthorn leaves. For these extracts, total polyphenol content, chemical composition, and antioxidant capacity were determined. The extracts obtained by this procedure present higher polyphenol content with a higher antioxidant capacity than those obtained by conventional methods performed at the same temperature profile and in the same extraction cell.

Extended RF shimming: Sequence-level parallel transmission optimization applied to steady-state free precession MRI of the heart.

Cardiac magnetic resonance imaging (MRI) at high field presents challenges because of the high specific absorption rate and significant transmit field (B 1 +) inhomogeneities. Parallel transmission MRI offers the ability to correct for both issues at the level of individual radiofrequency (RF) pulses, but must operate within strict hardware and safety constraints. The constraints are themselves affected by sequence parameters, such as the RF pulse duration and TR, meaning that an overall optimal operating point exists for a given sequence. This work seeks to obtain optimal performance by performing a ‘sequence‐level’ optimization in which pulse sequence parameters are included as part of an RF shimming calculation. The method is applied to balanced steady‐state free precession cardiac MRI with the objective of minimizing TR, hence reducing the imaging duration. Results are demonstrated using an eight‐channel parallel transmit system operating at 3 T, with an in vivo study carried out on seven male subjects of varying body mass index (BMI). Compared with single‐channel operation, a mean‐squared‐error shimming approach leads to reduced imaging durations of 32 ± 3% with simultaneous improvement in flip angle homogeneity of 32 ± 8% within the myocardium.

Safety of externally stimulated intracranial electrodes during functional MRI at 1.5 T

Surgical resection of the epileptogenic zone (EZ) is a potential cure for medically refractory focal epilepsy. Proper identification of the EZ is essential for such resection. Synergistic application of functional magnetic resonance imaging (fMRI) simultaneously with stimulation of a single externalized intracranial stereotactic EEG (SEEG) electrode has the potential to improve identification of the EZ. While most EEG-fMRI studies use the electrodes passively to record electrical activity, it is possible to stimulate the brain using the electrodes by connecting them with conducting cables to the stimulation hardware. In this study, we investigated the effect of MRI-induced heating on a single SEEG electrode and its sensitivity to geometry, configuration, and associated connections required for the stimulation. The temperature increase of a single electrode embedded within a gel phantom and connected to an external stimulation system was measured during 1.5T MRI scans using adjacent fluoroptic temperature sensors. A receive-only split-array head coil and a transmit-receive head coil were used for testing. Sequences included a standard localizer, T1-weighted axial fast low-angle shot (FLASH), gradient echo-planar imaging (GE-EPI) axial fMRI, and a high specific absorption rate T2-weighted turbo spin-echo (TSE) axial scan. Variations of the electrode location and connecting cable configuration were tested. No unacceptable heating was observed with the standard sequences used for evaluation of the EZ. Considerable heating (up to 14°C) was observed with the TSE sequence, which is not used clinically. The temperature increase was insignificant (<0.05°C) for electrode contacts closest to the isocenter and connecting cables lying along the isocenter, and varied with configurations of the connecting cable assembly. Simultaneous intracranial electrode stimulation during fMRI using an externalized stimulation system may be safe with strict adherence to settings tested prior to the fMRI. Localizer, FLASH, and GE-EPI fMRI may be safely performed in patients with a single SEEG electrode following the configurations tested in this study, but high SAR TSE scans should not be performed in these patients.