LIVIVO - Search results -

Search results

Result 1 - 10 of total 95

Search options

Article: Differential patterns of automatic segmentation of 3T and 7T MRI: Implications in neuropsychiatric disease.

Verma, Gaurav / Choi, Ki Sueng / Mayberg, Helen / Balchandani, Priti

bioRxiv : the preprint server for biology

2023

Abstract: Automatic segmentation was performed on T1-MPRAGE structural MRI data acquired at 3T and 7T from 37 and 69 distinct healthy controls, respectively. Additionally, segmentation was performed on imaging acquired from 215 major depressive disorder (MDD) ... ...

Abstract	Automatic segmentation was performed on T1-MPRAGE structural MRI data acquired at 3T and 7T from 37 and 69 distinct healthy controls, respectively. Additionally, segmentation was performed on imaging acquired from 215 major depressive disorder (MDD) patients at 3T and 40 MDD patients at 7T. Of 259 segmentation-derived imaging features evaluated, 120 showed significant 3T vs. 7T differences among controls, and 153 among patients. 7T imaging metrics showed consistently lower cortical thickness and cortical gray/white matter ratios. Subcortical and cortical volumes measured at 7T were more mixed, with 7T images showing greater frontal lobe volume, but lower cortical volumes elsewhere.
Language	English
Publishing date	2023-01-27
Publishing country	United States
Document type	Preprint
DOI	10.1101/2023.01.25.525542
Database	MEDical Literature Analysis and Retrieval System OnLINE

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾

Article ; Online: Ultrahigh field MR Neuroimaging.

Verma, Gaurav / Balchandani, Priti

Topics in magnetic resonance imaging : TMRI

2019 Volume 28, Issue 3, Page(s) 137–144

Language	English
Publishing date	2019-07-03
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	1112716-8
ISSN	1536-1004 ; 0899-3459
ISSN (online)	1536-1004
ISSN	0899-3459
DOI	10.1097/RMR.0000000000000210
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 3430: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (2.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: Enhancing the brain MRI at ultra-high field systems using a meta-array structure.

Alipour, Akbar / Seifert, Alan C / Delman, Bradley N / Hof, Patrick R / Fayad, Zahi A / Balchandani, Priti

Medical physics

2023 Volume 50, Issue 12, Page(s) 7606–7618

Abstract: Background: The main advantage of ultra-high field (UHF) magnetic resonance neuroimaging is theincreased signal-to-noise ratio (SNR) compared with lower field strength imaging. However, the wavelength effect associated with UHF MRI results in ... ...

Abstract	Background: The main advantage of ultra-high field (UHF) magnetic resonance neuroimaging is theincreased signal-to-noise ratio (SNR) compared with lower field strength imaging. However, the wavelength effect associated with UHF MRI results in radiofrequency (RF) inhomogeneity, compromising whole brain coverage for many commercial coils. Approaches to resolving this issue of transmit field inhomogeneity include the design of parallel transmit systems (PTx), RF pulse design, and applying passive RF shimming such as high dielectric materials. However, these methods have some drawbacks such as unstable material parameters of dielectric pads, high-cost, and complexity of PTx systems. Metasurfaces are artificial structures with a unique platform that can control the propagation of the electromagnetic (EM) waves, and they are very promising for engineering EM device. Implementation of meta-arrays enhancing MRI has been explored previously in several studies. Purpose: The aim of this study was to assess the effect of new meta-array technology on enhancing the brain MRI at 7T. A meta-array based on a hybrid structure consisting of an array of broadside-coupled split-ring resonators and high-permittivity materials was designed to work at the Larmor frequency of a 7 Tesla (7T) MRI scanner. When placed behind the head and neck, this construct improves the SNR in the region of the cerebellum,brainstem and the inferior aspect of the temporal lobes. Methods: Numerical electromagnetic simulations were performed to optimize the meta-array design parameters and determine the RF circuit configuration. The resultant transmit-efficiency and signal sensitivity improvements were experimentally analyzed in phantoms followed by healthy volunteers using a 7T whole-body MRI scanner equipped with a standard one-channel transmit, 32-channel receive head coil. Efficacy was evaluated through acquisition with and without the meta-array using two basic sequences: gradient-recalled-echo (GRE) and turbo-spin-echo (TSE). Results: Experimental phantom analysis confirmed two-fold improvement in the transmit efficiency and 1.4-fold improvement in the signal sensitivity in the target region. In vivo GRE and TSE images with the meta-array in place showed enhanced visualization in inferior regions of the brain, especially of the cerebellum, brainstem, and cervical spinal cord. Conclusion: Addition of the meta-array to commonly used MRI coils can enhance SNR to extend the anatomical coverage of the coil and improve overall MRI coil performance. This enhancement in SNR can be leveraged to obtain a higher resolution image over the same time slot or faster acquisition can be achieved with same resolution. Using this technique could improve the performance of existing commercial coils at 7T for whole brain and other applications.
MeSH term(s)	Humans ; Magnetic Resonance Imaging ; Neuroimaging ; Brain/diagnostic imaging ; Brain Stem ; Head ; Phantoms, Imaging ; Radio Waves ; Signal-To-Noise Ratio ; Equipment Design
Language	English
Publishing date	2023-10-24
Publishing country	United States
Document type	Journal Article
ZDB-ID	188780-4
ISSN	2473-4209 ; 0094-2405
ISSN (online)	2473-4209
ISSN	0094-2405
DOI	10.1002/mp.16801
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 1210: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: UltraHigh Field MR Imaging in Epilepsy.

Verma, Gaurav / Delman, Bradley N / Balchandani, Priti

Magnetic resonance imaging clinics of North America

2020 Volume 29, Issue 1, Page(s) 41–52

Abstract: More than one million people in the United States suffer from seizures that are not controlled with antiseizure medications. Targeted interventions such as surgery and deep brain stimulation can confer seizure reduction or even freedom in many of these ... ...

Abstract	More than one million people in the United States suffer from seizures that are not controlled with antiseizure medications. Targeted interventions such as surgery and deep brain stimulation can confer seizure reduction or even freedom in many of these patients with drug-resistant epilepsy, but success critically depends on identification of epileptogenic zones through MR imaging. Ultrahigh field imaging facilitates improved sensitivity and resolution across many imaging modalities and may facilitate better detection of epileptic markers than is achieved at lower field strengths. The increasing availability and clinical adoption of ultrahigh field scanners play an important role in characterizing drug-resistant epilepsy and planning for its treatment.
MeSH term(s)	Brain/diagnostic imaging ; Brain/physiopathology ; Epilepsy/diagnosis ; Epilepsy/physiopathology ; Humans ; Image Interpretation, Computer-Assisted/methods ; Magnetic Resonance Imaging/methods
Language	English
Publishing date	2020-12-06
Publishing country	United States
Document type	Journal Article ; Review
ZDB-ID	1196851-5
ISSN	1557-9786 ; 1064-9689
ISSN (online)	1557-9786
ISSN	1064-9689
DOI	10.1016/j.mric.2020.09.006
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Se 1375: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: Altered hippocampus and amygdala subregion connectome hierarchy in major depressive disorder.

Jacob, Yael / Morris, Laurel S / Verma, Gaurav / Rutter, Sarah B / Balchandani, Priti / Murrough, James W

Translational psychiatry

2022 Volume 12, Issue 1, Page(s) 209

Abstract: The hippocampus and amygdala limbic structures are critical to the etiology of major depressive disorder (MDD). However, there are no high-resolution characterizations of the role of their subregions in the whole brain network (connectome). Connectomic ... ...

Abstract	The hippocampus and amygdala limbic structures are critical to the etiology of major depressive disorder (MDD). However, there are no high-resolution characterizations of the role of their subregions in the whole brain network (connectome). Connectomic examination of these subregions can uncover disorder-related patterns that are otherwise missed when treated as single structures. 38 MDD patients and 40 healthy controls (HC) underwent anatomical and diffusion imaging using 7-Tesla MRI. Whole-brain segmentation was performed along with hippocampus and amygdala subregion segmentation, each representing a node in the connectome. Graph theory analysis was applied to examine the importance of the limbic subregions within the brain network using centrality features measured by node strength (sum of weights of the node's connections), Betweenness (number of shortest paths that traverse the node), and clustering coefficient (how connected the node's neighbors are to one another and forming a cluster). Compared to HC, MDD patients showed decreased node strength of the right hippocampus cornu ammonis (CA) 3/4, indicating decreased connectivity to the rest of the brain, and decreased clustering coefficient of the right dentate gyrus, implying it is less embedded in a cluster. Additionally, within the MDD group, the greater the embedding of the right amygdala central nucleus (CeA) in a cluster, the greater the severity of depressive symptoms. The altered role of these limbic subregions in the whole-brain connectome is related to diagnosis and depression severity, contributing to our understanding of the limbic system involvement in MDD and may elucidate the underlying mechanisms of depression.
MeSH term(s)	Amygdala/diagnostic imaging ; Brain ; Connectome ; Depressive Disorder, Major/diagnostic imaging ; Hippocampus/diagnostic imaging ; Humans ; Magnetic Resonance Imaging
Language	English
Publishing date	2022-05-19
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
ZDB-ID	2609311-X
ISSN	2158-3188 ; 2158-3188
ISSN (online)	2158-3188
ISSN	2158-3188
DOI	10.1038/s41398-022-01976-0
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Feasibility of Upper Cranial Nerve Sonication in Human Application via Neuronavigated Single-Element Pulsed Focused Ultrasound.

Brinker, Spencer T / Balchandani, Priti / Seifert, Alan C / Kim, Hyo-Jin / Yoon, Kyungho

Ultrasound in medicine & biology

2022 Volume 48, Issue 6, Page(s) 1045–1057

Abstract: Sonicating deep brain regions with pulsed focused ultrasound using magnetic resonance imaging-guided neuronavigation single-element piezoelectric transducers is a new area of exploration for neuromodulation. Upper cranial nerves such as the trigeminal ... ...

Abstract	Sonicating deep brain regions with pulsed focused ultrasound using magnetic resonance imaging-guided neuronavigation single-element piezoelectric transducers is a new area of exploration for neuromodulation. Upper cranial nerves such as the trigeminal nerve and other nerves responsible for sensory/motor functions in the head may be potential targets for ultrasound pain therapy. The location of upper cranial nerves close to the skull base poses additional challenges when compared with conventional cortical or middle brain targets. In the work described here, a series of computational and empirical testing methods using human skull specimens were conducted to assess the feasibility of sonicating the trigeminal pathway near the sphenoid bone region. The results indicate a transducer with a focal length of 120 mm and diameter of 85 mm (350 kHz) can deliver sonication to upper cranial nerve regions with spatial accuracy comparable to that of focused ultrasound brain targets used in previous human studies. Temperature measurements in cortical bone and in the skull base with embedded thermocouples yield evidence of minimal bone heating. Conventional pulse parameters were found to cause reverberation interference patterns near the cranial floor; therefore, changes in pulse cycles and pulse repetition frequency were examined for reducing standing waves. Limitations and considerations for conducting ultradeep focal targeting in human applications are discussed.
MeSH term(s)	Brain ; Cranial Nerves ; Feasibility Studies ; Humans ; Skull/diagnostic imaging ; Skull/surgery ; Sonication
Language	English
Publishing date	2022-03-25
Publishing country	England
Document type	Journal Article
ZDB-ID	186150-5
ISSN	1879-291X ; 0301-5629
ISSN (online)	1879-291X
ISSN	0301-5629
DOI	10.1016/j.ultrasmedbio.2022.01.022
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 963: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: Near-peers effectively teach clinical documentation skills to early medical students.

Kusnoor, Anita Vijay / Balchandani, Rajeev / Pillow, Malford Tyson / Sherman, Stephanie / Ismail, Nadia

BMC medical education

2022 Volume 22, Issue 1, Page(s) 712

Abstract: ... on written assessments after the workshop did not differ between the groups (29.3/30 for a written H&P and 9 ...

Abstract	Background: Composing the History of Present Illness (HPI), a key component of medical communication, requires critical thinking. Small group learning strategies have demonstrated superior effectiveness at developing critical thinking skills. Finding sufficient faculty facilitators for small groups remains a major gap in implementing these sessions. We hypothesized that "near-peer" teachers could effectively teach HPI documentation skills and fill the gap of small group facilitators. Here, we present a head-to-head comparison of near-peer and faculty teaching outcomes. Methods: Second-year medical students in a single institution participated in an HPI Workshop as a clinical skills course requirement. Students were randomly assigned a near-peer or faculty facilitator for the workshop. We compared mean facilitator evaluation scores and performance assessments of students assigned to either type of facilitator. Results: Three hundred sixty-five students, 29 residents (near-peers) and 16 faculty participated. On post-session evaluations (5-point Likert scale), students ranked near-peer facilitators higher than faculty facilitators on encouraging participation and achieving the goals of the session (residents 4.9, faculty 4.8), demonstrating small, statistically significant differences between groups. Mean scores on written assessments after the workshop did not differ between the groups (29.3/30 for a written H&P and 9/10 for an HPI exam question). Conclusions: Near-peer facilitators were as effective as faculty facilitators for the HPI Workshop. Utilizing near-peers to teach HPI documentation skills provided teaching experiences for residents and increased the pool of available facilitators.
MeSH term(s)	Clinical Competence ; Documentation ; Humans ; Peer Group ; Students, Medical ; Teaching ; Thinking
Language	English
Publishing date	2022-10-08
Publishing country	England
Document type	Journal Article ; Randomized Controlled Trial
ZDB-ID	2044473-4
ISSN	1472-6920 ; 1472-6920
ISSN (online)	1472-6920
ISSN	1472-6920
DOI	10.1186/s12909-022-03790-0
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: A Novel Method to Measure Venular Perivascular Spaces in Patients with MS on 7T MRI.

George, I C / Arrighi-Allisan, A / Delman, B N / Balchandani, P / Horng, S / Feldman, R

AJNR. American journal of neuroradiology

2021 Volume 42, Issue 6, Page(s) 1069–1072

Abstract: In MS, inflammatory cells accumulate within the perivascular spaces of acute and chronic lesions. Reliance on perivascular spaces as biomarkers for MS remains uncertain because various studies have reported inconsistencies in perivascular space anatomy. ... ...

Abstract	In MS, inflammatory cells accumulate within the perivascular spaces of acute and chronic lesions. Reliance on perivascular spaces as biomarkers for MS remains uncertain because various studies have reported inconsistencies in perivascular space anatomy. Distinguishing between venular and arteriolar perivascular spaces is pathophysiologically relevant in MS. In this pilot study, we leverage susceptibility-weighted imaging at 7T to better identify perivascular spaces of venular distribution on corresponding high-resolution T2 images.
MeSH term(s)	Adult ; Brain ; Female ; Glymphatic System ; Humans ; Magnetic Resonance Imaging ; Male ; Pilot Projects ; Reproducibility of Results
Language	English
Publishing date	2021-04-15
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural
ZDB-ID	603808-6
ISSN	1936-959X ; 0195-6108
ISSN (online)	1936-959X
ISSN	0195-6108
DOI	10.3174/ajnr.A7144
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 1580: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article ; Online: Ultra-High-Field MR Neuroimaging.

Balchandani, P / Naidich, T P

AJNR. American journal of neuroradiology

2015 Volume 36, Issue 7, Page(s) 1204–1215

Abstract: At ultra-high magnetic fields, such as 7T, MR imaging can noninvasively visualize the brain in unprecedented detail and through enhanced contrast mechanisms. The increased SNR and enhanced contrast available at 7T enable higher resolution anatomic and ... ...

Abstract	At ultra-high magnetic fields, such as 7T, MR imaging can noninvasively visualize the brain in unprecedented detail and through enhanced contrast mechanisms. The increased SNR and enhanced contrast available at 7T enable higher resolution anatomic and vascular imaging. Greater spectral separation improves detection and characterization of metabolites in spectroscopic imaging. Enhanced blood oxygen level-dependent contrast affords higher resolution functional MR imaging. Ultra-high-field MR imaging also facilitates imaging of nonproton nuclei such as sodium and phosphorus. These improved imaging methods may be applied to detect subtle anatomic, functional, and metabolic abnormalities associated with a wide range of neurologic disorders, including epilepsy, brain tumors, multiple sclerosis, Alzheimer disease, and psychiatric conditions. At 7T, however, physical and hardware limitations cause conventional MR imaging pulse sequences to generate artifacts, requiring specialized pulse sequences and new hardware solutions to maximize the high-field gain in signal and contrast. Practical considerations for ultra-high-field MR imaging include cost, siting, and patient experience.
MeSH term(s)	Artifacts ; Humans ; Magnetic Resonance Imaging/methods ; Neuroimaging/methods
Language	English
Publishing date	2015-07
Publishing country	United States
Document type	Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Review
ZDB-ID	603808-6
ISSN	1936-959X ; 0195-6108
ISSN (online)	1936-959X
ISSN	0195-6108
DOI	10.3174/ajnr.A4180
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Full text

In stock of ZB MED Cologne/Königswinter

Zs.A 1580: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾

Article ; Online: A semiadiabatic spectral-spatial spectroscopic imaging (SASSI) sequence for improved high-field MR spectroscopic imaging.

Feldman, Rebecca E / Balchandani, Priti

Magnetic resonance in medicine

2016 Volume 76, Issue 4, Page(s) 1071–1082

Abstract: Purpose: MR spectroscopic imaging (MRSI) benefits from operation at 7T due to increased signal-to-noise ratio (SNR) and spectral separation. The 180° radiofrequency (RF) pulses used in the conventional MRSI sequences are particularly susceptible to the ... ...

Abstract	Purpose: MR spectroscopic imaging (MRSI) benefits from operation at 7T due to increased signal-to-noise ratio (SNR) and spectral separation. The 180° radiofrequency (RF) pulses used in the conventional MRSI sequences are particularly susceptible to the variation in the transmitted RF (B1 ) field and severe chemical shift localization errors at 7T. RF power deposition, as measured by specific absorption rate (SAR), also increases with field strength. Adiabatic 180° RF pulses may mitigate the effects of B1 variation. We designed and implemented a semiadiabatic spectral-spatial spectroscopic imaging (SASSI) pulse sequence to provide more uniform spectral data at 7T with reduced SAR. Methods: The adiabatic Shinnar-Le Roux algorithm was used to generate a high bandwidth 180° adiabatic spectral-spatial (SPSP) pulse that captured a spectral range containing the main metabolites of interest. A pair of 180° SPSP pulses was used to refocus the signal excited by a 90° SPSP pulse in order to select a 3D volume of interest in the SASSI sequence. Results: The SASSI pulse sequence produced spectra with more uniform brain metabolite SNR when compared with the conventional nonadiabatic MRSI sequence. Conclusion: SASSI achieved comparable SNR to the current adiabatic alternative, semi-LASER, but with 1/3 of the SAR. Magn Reson Med 76:1071-1082, 2016. © 2015 Wiley Periodicals, Inc.
Language	English
Publishing date	2016-10
Publishing country	United States
Document type	Journal Article
ZDB-ID	605774-3
ISSN	1522-2594 ; 0740-3194
ISSN (online)	1522-2594
ISSN	0740-3194
DOI	10.1002/mrm.26025
Database	MEDical Literature Analysis and Retrieval System OnLINE

Full text online

Accessible to users with ZB MED library card

In stock of ZB MED Cologne/Königswinter

Zs.A 1959: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾

To top

More links

Kategorien

Inter-library loan at ZB MED

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

Full text online

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

Full text online

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito