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https://www.readbyqxmd.com/read/28314207/a-pulse-sequence-for-singlet-to-heteronuclear-magnetization-transfer-s2hm
#1
Gabriele Stevanato, James Eills, Christian Bengs, Giuseppe Pileio
We have recently demonstrated, in the context of para-hydrogen induced polarization (PHIP), the conversion of hyperpolarized proton singlet order into heteronuclear magnetisation can be efficiently achieved via a new sequence named S2hM (Singlet to heteronuclear Magnetisation). In this paper we give a detailed theoretical description, supported by an experimental illustration, of S2hM. Theory and experiments on thermally polarized samples demonstrate the proposed method is robust to frequency offset mismatches and radiofrequency field inhomogeneities...
March 6, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28302606/trochlear-groove-and-trochlear-cistern-useful-anatomic-landmarks-for-identifying-the-tentorial-segment-of-cranial-nerve-iv-on-mri
#2
P M Bunch, H R Kelly, D A Zander, H D Curtin
BACKGROUND AND PURPOSE: The trochlear groove and trochlear cistern are anatomic landmarks closely associated with the tentorial segment of cranial nerve IV. The purposes of this study were to describe the MR imaging appearances of the trochlear groove and trochlear cistern and to test our hypothesis that knowledge of these anatomic landmarks facilitates identification of cranial nerve IV in routine clinical practice. MATERIALS AND METHODS: For this retrospective study, consecutive MR imaging examinations of the sinuses performed in 25 patients (50 sides) at our institution were reviewed...
March 16, 2017: AJNR. American Journal of Neuroradiology
https://www.readbyqxmd.com/read/28298111/-1-h-2-h-cross-polarization-nmr-in-fast-spinning-solids-by-adiabatic-sweeps
#3
Sungsool Wi, Robert Schurko, Lucio Frydman
Cross-polarization (CP) experiments employing frequency-swept radiofrequency (rf) pulses have been successfully used in static spin systems for obtaining broadband signal enhancements. These experiments have been recently extended to heteronuclear I, S = spin-1/2 nuclides under magic-angle spinning (MAS), by applying adiabatic inversion pulses along the S (low-γ) channel while simultaneously applying a conventional spin-locking pulse on the I-channel ((1)H). This study explores an extension of this adiabatic frequency sweep concept to quadrupolar nuclei, focusing on CP from (1)H (I = 1/2) to (2)H spins (S = 1) undergoing fast MAS (νr = 60 kHz)...
March 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28285487/load-carriage-related-paresthesias-part-2-meralgia-paresthetica
#4
Joseph J Knapik, Katy Reynolds, Robin Orr, Rodney Pope
This is the second of a two-part series addressing symptoms, evaluation, and treatment of load carriage- related paresthesias. Part 1 addressed rucksack palsy and digitalgia paresthetica; here, meralgia paresthetica (MP) is discussed. MP is a mononeuropathy involving the lateral femoral cutaneous nerve (LFCN). MP has been reported in load carriage situations where the LFCN was compressed by rucksack hipbelts, pistol belts, parachute harnesses, and body armor. In the US military, the rate of MP is 6.2 cases/10,000 personyears...
2017: Journal of Special Operations Medicine: a Peer Reviewed Journal for SOF Medical Professionals
https://www.readbyqxmd.com/read/28285143/adiabatic-sweep-cross-polarization-magic-angle-spinning-nmr-of-half-integer-quadrupolar-spins
#5
Sungsool Wi, Chul Kim, Robert Schurko, Lucio Frydman
The use of frequency-swept radiofrequency (rf) pulses for enhancing signals in the magic-angle spinning (MAS) spectra of half-integer quadrupolar nuclides was explored. The broadband adiabatic inversion cross-polarization magic-angle spinning (BRAIN-CPMAS) method, involving an adiabatic inversion pulse on the S-channel and a simultaneous rectangular spin-lock pulse on the I-channel ((1)H), was applied to I(1/2)→S(3/2) systems. Optimal BRAIN-CPMAS matching conditions were found to involve low rf pulse strengths for both the I- and S-spin channels...
March 2, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28274357/laser-and-light-based-treatments-of-acne-and-acne-scarring
#6
Macrene Alexiades
The treatment of acne and acne scarring with lasers and light-based and energy-based technologies has become an integral component of our therapeutic arsenal. Lasers including infrared wavelengths and pulsed dye lasers; light devices including blue light, red light, and broadband light; and photodynamic therapy with aminolevulinic acid and methylaminolevulinic acid have been shown to be effective in the treatment of acne vulgaris. The optimal outcomes are achieved with photodynamic therapy combined with medical therapy...
March 2017: Clinics in Dermatology
https://www.readbyqxmd.com/read/28251523/atypical-facial-pain-a-comprehensive-evidence-based-review
#7
REVIEW
Austin L Weiss, Ken P Ehrhardt, Reda Tolba
PURPOSE OF REVIEW: The purpose of this article is to focus on an excruciating disorder of the face, named atypical facial pain or persistent idiopathic facial pain (PIFP). It is considered an underdiagnosed condition with limited treatment options. Facial pain can be a debilitating disorder that affects patients' quality of life. Up to 26% of the general population has suffered from facial pain at some point in their lives. It is important to highlight the different types of facial pain to be able to properly manage this condition accordingly...
February 2017: Current Pain and Headache Reports
https://www.readbyqxmd.com/read/28249536/linear-rogowski-coil
#8
V Nassisi, D Delle Side
Nowadays, the employment and development of fast current pulses require sophisticated systems to perform measurements. Rogowski coils are used to diagnose cylindrical shaped beams; therefore, they are designed and built with a toroidal structure. Recently, to perform experiments of radiofrequency biophysical stresses, flat transmission lines have been developed. Therefore, in this work we developed a linear Rogowski coil to detect current pulses inside flat conductors. The system is first approached by means of transmission line theory...
February 2017: Review of Scientific Instruments
https://www.readbyqxmd.com/read/28248888/comparison-between-bipolar-pulsed-radiofrequency-and-monopolar-pulsed-radiofrequency-in-chronic-lumbosacral-radicular-pain-a-randomized-controlled-trial
#9
Min Cheol Chang, Yun Woo Cho, Sang Ho Ahn
BACKGROUND: Chronic lumbosacral radicular pain is a challenging medical problem with respect to therapeutic management. Many patients with lumbosacral radicular pain complain of persistent leg pain after transforaminal epidural steroid injection. Nowadays, pulsed radiofrequency (PRF) stimulation on the dorsal root ganglion (DRG) is widely used for controlling lumbosacral radicular pain. METHODS: We evaluated the effect of bipolar PRF on the DRG for the management of lumbosacral radicular pain...
March 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28244136/improved-fat-suppression-of-the-breast-using-discretized-frequency-shimming
#10
Tijl A van der Velden, Peter R Luijten, Dennis W J Klomp
PURPOSE: Robust fat suppression is essential in bilateral breast MRI at 7 Tesla. The lack of good fat suppression can result in errors when calculating the enhancement curve from dynamic contrast-enhanced acquisitions. In this work we propose discretized frequency shimming to improve the quality of fat suppression by exploiting the capabilities of a parallel transmit setup. METHODS: With discretized frequency shimming, different resonance frequencies are used for the different transmitters of the radiofrequency coil...
February 28, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28242234/associations-between-common-carotid-artery-diameter-framingham-risk-score-and-cardiovascular-events
#11
M Kozakova, C Morizzo, S La Carrubba, I Fabiani, D Della Latta, J Jamagidze, D Chiappino, V Di Bello, C Palombo
BACKGROUND AND AIMS: Vascular biomarkers are associated with risk burden and are capable to predict the development of future cardiovascular (CV) events; yet, their additive predictive value over and above established risk algorithms seems to be only modest. The present study evaluated the cross-sectional associations between vascular biomarkers, 10-year Framingham risk (FR) and prevalent CV events in a population with a high prevalence of hypertension and diabetes. METHODS AND RESULTS: As many as 681 subjects (419 men, age = 60 ± 10 years, 282 diabetics, 335 hypertensives, mean FR score = 22...
January 12, 2017: Nutrition, Metabolism, and Cardiovascular Diseases: NMCD
https://www.readbyqxmd.com/read/28237869/the-role-of-image-guided-therapy-in-the-management-of-colorectal-cancer-metastatic-disease
#12
REVIEW
Thierry de Baere, Lambros Tselikas, Steven Yevich, Valérie Boige, Frederic Deschamps, Michel Ducreux, Diane Goere, France Nguyen, David Malka
The European Society for Medical Oncology (ESMO) have stressed that the option for treating oligometastatic disease is a strategy of local ablative therapy, the goal of which is to improve disease control. The spectrum of the local ablative therapy toolbox described by the ESMO includes surgical R0 resection, percutaneous ablation and intra-arterial therapies, the choice of treatment being left to the multidisciplinary team. Interventional therapy involving image-guided treatment offers the possibility of less invasive treatments for colorectal cancer metastases in the liver, lung and bone by preserving from toxicity distant healthy organs or even parts of the diseased organs...
February 23, 2017: European Journal of Cancer
https://www.readbyqxmd.com/read/28222392/endor-with-band-selective-shaped-inversion-pulses
#13
Claudia E Tait, Stefan Stoll
Electron Nuclear DOuble Resonance (ENDOR) is based on the measurement of nuclear transition frequencies through detection of changes in the polarization of electron transitions. In Davies ENDOR, the initial polarization is generated by a selective microwave inversion pulse. The rectangular inversion pulses typically used are characterized by a relatively low selectivity, with full inversion achieved only for a limited number of spin packets with small resonance offsets. With the introduction of pulse shaping to EPR, the rectangular inversion pulses can be replaced with shaped pulses with increased selectivity...
February 12, 2017: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/28220602/mexametric-and-cutometric-assessment-of-the-signs-of-aging-of-the-skin-area-around-the-eyes-after-the-use-of-non-ablative-fractional-laser-non-ablative-radiofrequency-and-intense-pulsed-light
#14
Anna Maria Kołodziejczak, Helena Rotsztejn
The assessment of the signs of aging within eyes area in cutometric (skin elasticity) and mexametric (discoloration and severity of erythema) examination after the treatment with: non-ablative fractional laser, non-ablative radiofrequency (RF) and intense light source (IPL). This study included 71 patients, aged 33-63 years (the average age was 45.81) with Fitzpatrick skin type II and III. 24 patients received 5 successive treatment sessions with a 1,410-nm non-ablative fractional laser in two-week intervals, 23 patients received 5 successive treatment sessions with a non-ablative RF in one-week intervals and 24 patients received 5 successive treatment sessions with an IPL in two-week intervals...
February 21, 2017: Dermatologic Therapy
https://www.readbyqxmd.com/read/28217060/ultrasonography-guided-pulsed-radiofrequency-of-sciatic-nerve-for-the-treatment-of-complex-regional-pain-syndrome-type-ii
#15
Yi Hwa Choi, Dong Jin Chang, Woon Suk Hwang, Jin Hwan Chung
Although the major mechanism of complex regional pain syndrome (CRPS) involves dysfunctional central or sympathetic nervous system activation, the peripheral nervous system also contributes significantly to its clinical manifestations. Pulsed radiofrequency (PRF) is a recently developed treatment option for neuropathic pain syndromes. Here, we report a case of CRPS Type II after a femur fracture and sciatic nerve injury, in which the pain was treated successfully with ultrasonography-guided selective sciatic nerve PRF application...
January 2017: Saudi Journal of Anaesthesia
https://www.readbyqxmd.com/read/28209507/ultrasound-guided-pulsed-radiofrequency-stimulation-of-posterior-tibial-nerve-a-potential-novel-intervention-for-recalcitrant-plantar-fasciitis
#16
Yung-Tsan Wu, Chih-Ya Chang, Yu-Ching Chou, Chun-Chang Yeh, Tsung-Ying Li, Heng-Yi Chu, Liang-Cheng Chen
OBJECTIVE: To evaluate the therapeutic benefit of ultrasound-guided pulsed radiofrequency (PRF) stimulation at the posterior tibial nerve (PTN) in patients with recalcitrant plantar fasciitis (PF). DESIGN: A prospective, randomized, double-blinded, placebo-controlled trial (12-week follow-up). SETTING: Outpatient of local medical center settings. PARTICIPANTS: Thirty-six patients with recalcitrant PF were randomized and 36 participants were included in the final data analysis...
February 13, 2017: Archives of Physical Medicine and Rehabilitation
https://www.readbyqxmd.com/read/28204748/successful-pulsed-radiofrequency-for-lumbosacral-radicular-pain-not-so-easy-to-predict
#17
Ulderico Freo, Giuseppe Calcarella
No abstract text is available yet for this article.
February 1, 2017: Pain Medicine: the Official Journal of the American Academy of Pain Medicine
https://www.readbyqxmd.com/read/28202630/targets-and-end-points-in-cardiac-autonomic-denervation-procedures
#18
Esteban W Rivarola, Denise Hachul, Tan Wu, Cristiano Pisani, Carina Hardy, Fabrizio Raimundi, Sissy Melo, Francisco Darrieux, Mauricio Scanavacca
BACKGROUND: Autonomic denervation is an alternative approach for patients with symptomatic bradycardia. No consensus exists on the critical targets and end points of the procedure. The aim of this study was to identify immediate end points and critical atrial regions responsible for vagal denervation. METHODS AND RESULTS: We enrolled 14 patients (50% men; age: 34.0±13.8 years) with cardioinhibitory syncope, advanced atrioventricular block or sinus arrest, and no structural heart disease...
February 2017: Circulation. Arrhythmia and Electrophysiology
https://www.readbyqxmd.com/read/28195684/extended-rf-shimming-sequence-level-parallel-transmission-optimization-applied-to-steady-state-free-precession-mri-of-the-heart
#19
Arian Beqiri, Anthony N Price, Francesco Padormo, Joseph V Hajnal, Shaihan J Malik
Cardiac magnetic resonance imaging (MRI) at high field presents challenges because of the high specific absorption rate and significant transmit field (B1(+) ) 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...
February 14, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28195663/optimization-of-inhomogeneous-magnetization-transfer-ihmt-mri-contrast-for-preclinical-studies-using-dipolar-relaxation-time-t1d-filtering
#20
V H Prevost, O M Girard, S Mchinda, G Varma, D C Alsop, G Duhamel
A pulsed inhomogeneous magnetization transfer (ihMT)-prepared fast imaging sequence was implemented at 11.75 T for preclinical studies on mouse central nervous system. A strategy based on filtering the ihMT signal originating from short dipolar relaxation time (T1D ) components is proposed. It involves increasing the repetition time of consecutive radiofrequency (RF) pulses of the dual saturation and allows improved signal specificity for long T1D myelinated structures. Furthermore, frequency offset, power and timing saturation parameters were adjusted to optimize the ihMT sensitivity...
February 14, 2017: NMR in Biomedicine
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