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  1. 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
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  2. Article ; Online: Special MRI Techniques to Suss out Spontaneous Cerebrospinal Fluid Leaks.

    Yushvayev, Ernest / Delman, Bradley N / Kirsch, Claudia F E

    Topics in magnetic resonance imaging : TMRI

    2021  Volume 30, Issue 3, Page(s) 159–166

    Abstract: Abstract: Anterior skull base cerebrospinal fluid (CSF) fistulas result from skull base osteodural defects, allowing subarachnoid space CSF to escape into pneumatized cavities such as the paranasal sinuses and nasal fossa. Precise localization, ... ...

    Abstract Abstract: Anterior skull base cerebrospinal fluid (CSF) fistulas result from skull base osteodural defects, allowing subarachnoid space CSF to escape into pneumatized cavities such as the paranasal sinuses and nasal fossa. Precise localization, characterization, and effective treatment of CSF leaks is essential to prevent meningitis, treatment failure, or recurrence. Advances in magnetic resonance imaging have improved radiologists' ability to localize and characterize anterior skull base CSF fistulas. This article reviews new imaging techniques enabling diagnostic location of CSF fistulas, with an emphasis on magnetic resonance imaging-based techniques.
    MeSH term(s) Cerebrospinal Fluid Leak/diagnostic imaging ; Cerebrospinal Fluid Leak/therapy ; Humans ; Magnetic Resonance Imaging/methods ; Skull Base/diagnostic imaging ; Treatment Outcome
    Language English
    Publishing date 2021-06-07
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1112716-8
    ISSN 1536-1004 ; 0899-3459
    ISSN (online) 1536-1004
    ISSN 0899-3459
    DOI 10.1097/RMR.0000000000000281
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  3. 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
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  4. Article ; Online: Third Ventricular Subependymomas: Clinical Features and Outcomes Over Two Decades.

    Carr, Matthew T / Hernandez-Marquez, Gianina C / Vij, Meenakshi / Chin, Xing / Delman, Bradley N / Umphlett, Melissa / Germano, Isabelle M

    World neurosurgery

    2023  Volume 175, Page(s) e81–e89

    Abstract: Background: Subependymomas are uncommon, benign slow-growing neoplasms of the central nervous system preferentially arising within the fourth and lateral ventricles. Third ventricle involvement has been described rarely. The aim of this study is to ... ...

    Abstract Background: Subependymomas are uncommon, benign slow-growing neoplasms of the central nervous system preferentially arising within the fourth and lateral ventricles. Third ventricle involvement has been described rarely. The aim of this study is to provide the first systematic review of third ventricular subependymomas (TVSE) by analyzing all reported cases over 2 decades and describing a case example.
    Methods: MEDLINE and Embase databases were searched for the 20 years ending January 1, 2022, using relevant MeSH and non-MeSH terms, including "subependymoma" and "third ventricle." Methodology followed PRISMA guidelines.
    Results: Of 804 identified studies, 131 met inclusion eligibility. The literature yielded 17 patients with TVSE plus our example (18 total). Of these patients, 83% (15/18) presented in adulthood (average age, 42 ± 19 years), of whom 73% were women. The pediatric cohort age was 5 ± 1 years, 67% (4/6) of whom were girls. The most common presenting symptom in both cohorts was headache (80%), followed by memory disturbances and vomitus. In adults, symptomatic tumors were approached by open craniotomy in all but 1 case, most using a transcallosal approach. Gross total resection was obtained in 73%. A ventriculoperitoneal shunt was inserted in 2/15 adult and 4/6 pediatric patients. Overall, both cohorts showed symptomatic improvement without disease recurrence. One patient died perioperatively.
    Conclusions: Subependymomas should be considered in the differential diagnosis of third ventricular tumors. The clinical presentation of TVSE mainly parallels hydrocephalus symptoms and, hence, awareness is of vital importance for timely treatment. The surgical goal should be gross total resection, which can be curative and offers greatest clinical improvement across the population.
    MeSH term(s) Adult ; Humans ; Child ; Female ; Young Adult ; Middle Aged ; Child, Preschool ; Male ; Cerebral Ventricle Neoplasms/diagnostic imaging ; Cerebral Ventricle Neoplasms/surgery ; Third Ventricle/diagnostic imaging ; Third Ventricle/surgery ; Third Ventricle/pathology ; Neoplasm Recurrence, Local ; Glioma, Subependymal/diagnostic imaging ; Glioma, Subependymal/surgery ; Brain Neoplasms/surgery
    Language English
    Publishing date 2023-03-12
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2534351-8
    ISSN 1878-8769 ; 1878-8750
    ISSN (online) 1878-8769
    ISSN 1878-8750
    DOI 10.1016/j.wneu.2023.03.031
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  5. Article ; Online: Quantification of brain age using high-resolution 7 tesla MR imaging and implications for patients with epilepsy.

    Verma, Gaurav / Jacob, Yael / Jha, Manish / Morris, Laurel S / Delman, Bradley N / Marcuse, Lara / Fields, Madeline / Balchandani, Priti

    Epilepsy & behavior reports

    2022  Volume 18, Page(s) 100530

    Abstract: Purpose: Epilepsy patients exhibit morphological differences on neuroimaging compared to age-matched healthy controls, including cortical and sub-cortical volume loss and altered gray-white matter ratios. The objective was to develop a model of normal ... ...

    Abstract Purpose: Epilepsy patients exhibit morphological differences on neuroimaging compared to age-matched healthy controls, including cortical and sub-cortical volume loss and altered gray-white matter ratios. The objective was to develop a model of normal aging using the 7T MRIs of healthy controls. This model can then be used to determine if the changes in epilepsy patients resemble the changes seen in aging, and potentially give a marker for the severity of those changes.
    Methods: Sixty-nine healthy controls (24F/45M, mean age 36.5 ± 10.5 years) and forty-four epilepsy patients (24F/20M, 33.2 ± 9.9 years) non-lesional at 3T were scanned with volumetric T1-MPRAGE at 7T. These images were segmented and quantified using FreeSurfer. A linear regression-based model trained on healthy controls was developed to predict ages using derived imaging features among the epilepsy patient cohort. The model used 114 features with significant linear correlation with age.
    Results: The regression-based model estimated brain age with mean absolute error (MAE) of 6.6 years among controls. Comparable prediction accuracy of 6.9 years MAE was seen epilepsy patients. T-test of mean absolute error showed no difference in the prediction accuracy with controls and epilepsy patients (
    Major conclusions: Morphological patterns suggestive of premature aging were observed in non-lesional epilepsy patients vs. controls and in high seizure frequency patients vs. low frequency patients. Modeling brain age with 7T MRI may provide a sensitive imaging marker to assess the differential effects of the aging process in diseases such as epilepsy.
    Language English
    Publishing date 2022-02-22
    Publishing country United States
    Document type Journal Article
    ISSN 2589-9864
    ISSN (online) 2589-9864
    DOI 10.1016/j.ebr.2022.100530
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  6. Article ; Online: Frontline Practices in Response to Monkeypox Outbreak in New York City.

    Leong, Tin / Riveros, Daniela / Delman, Bradley N / Moss, Marie K / Javaid, Waleed / Rodriguez, Harold / Kagetsu, Nolan J

    Journal of the American College of Radiology : JACR

    2022  Volume 21, Issue 4, Page(s) e7–e9

    MeSH term(s) Humans ; Mpox (monkeypox) ; New York City/epidemiology ; Disease Outbreaks
    Language English
    Publishing date 2022-10-03
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2274861-1
    ISSN 1558-349X ; 1546-1440
    ISSN (online) 1558-349X
    ISSN 1546-1440
    DOI 10.1016/j.jacr.2022.09.025
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  7. Article ; Online: Imaging of pediatric pituitary abnormalities.

    Delman, Bradley N

    Endocrinology and metabolism clinics of North America

    2009  Volume 38, Issue 4, Page(s) 673–698

    Abstract: Evaluation of the sella and surrounding structures in pediatric endocrinopathies is best performed with high-resolution magnetic resonance imaging. Adequate assessment relies not only on determining the size and shape of the gland but also on confirming ... ...

    Abstract Evaluation of the sella and surrounding structures in pediatric endocrinopathies is best performed with high-resolution magnetic resonance imaging. Adequate assessment relies not only on determining the size and shape of the gland but also on confirming normal signal characteristics and homogeneous parenchymal enhancement. Surrounding structures, including the hypothalamus-infundibulum-stalk and the skull base and midline structures about the cerebral hemispheres, warrant careful attention to identify any associated abnormalities. Tumors, whether they arise in the gland or affect gland function through mass effect, are usually well resolved on today's scanners and imaging provides accurate characterization of these lesions.
    MeSH term(s) Adenoma/diagnosis ; Child ; Cysts/diagnosis ; Diagnostic Imaging/methods ; Diagnostic Imaging/trends ; Humans ; Models, Biological ; Organ Size ; Pituitary Diseases/congenital ; Pituitary Diseases/diagnosis ; Pituitary Gland/abnormalities ; Pituitary Gland/anatomy & histology ; Pituitary Gland/embryology ; Pituitary Neoplasms/diagnosis
    Language English
    Publishing date 2009-12
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 92116-6
    ISSN 1558-4410 ; 0889-8529
    ISSN (online) 1558-4410
    ISSN 0889-8529
    DOI 10.1016/j.ecl.2009.09.001
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  8. Article ; Online: Dose length product to effective dose coefficients in children.

    Chu, Philip W / Kofler, Cameron / Mahendra, Malini / Wang, Yifei / Chu, Cameron A / Stewart, Carly / Delman, Bradley N / Haas, Brian / Lee, Choonsik / Bolch, Wesley E / Smith-Bindman, Rebecca

    Pediatric radiology

    2023  Volume 53, Issue 8, Page(s) 1659–1668

    Abstract: Background: The most accurate method for estimating effective dose (the most widely understood metric for tracking patient radiation exposure) from computed tomography (CT) requires time-intensive Monte Carlo simulation. A simpler method multiplies a ... ...

    Abstract Background: The most accurate method for estimating effective dose (the most widely understood metric for tracking patient radiation exposure) from computed tomography (CT) requires time-intensive Monte Carlo simulation. A simpler method multiplies a scalar coefficient by the widely available scanner-reported dose length product (DLP) to estimate effective dose.
    Objective: Develop pediatric effective dose coefficients and assess their agreement with Monte Carlo simulation.
    Materials and methods: Multicenter, population-based sample of 128,397 pediatric diagnostic CT scans prospectively assembled in 2015-2020 from the University of California San Francisco International CT Dose Registry and the University of Florida library of highly realistic hybrid computational phantoms. We generated effective dose coefficients for seven body regions, stratified by patient age, diameter, and scanner manufacturer. We applied the new coefficients to DLPs to calculate effective doses and assessed their correlations with Monte Carlo radiation transport-generated effective doses.
    Results: The reported effective dose coefficients, generally higher than previous studies, varied by body region and decreased in magnitude with increasing age. Coefficients were approximately 4 to 13-fold higher (across body regions) for patients  <1 year old compared with patients 15-21 years old. For example, head CT (54% of scans) dose coefficients decreased from 0.039 to 0.003 mSv/mGy-cm in patients  <1 year old vs. 15-21 years old. There were minimal differences by manufacturer. Using age-based conversion coefficients to estimate effective dose produced moderate to strong correlations with Monte Carlo results (Pearson correlations 0.52-0.80 across body regions).
    Conclusions: New pediatric effective dose coefficients update existing literature and can be used to easily estimate effective dose using scanner-reported DLP.
    MeSH term(s) Infant ; Humans ; Child ; Adolescent ; Young Adult ; Adult ; Radiation Dosage ; Radiometry/methods ; Tomography, X-Ray Computed/methods ; Computer Simulation ; Phantoms, Imaging ; Monte Carlo Method
    Language English
    Publishing date 2023-03-16
    Publishing country Germany
    Document type Multicenter Study ; Journal Article
    ZDB-ID 124459-0
    ISSN 1432-1998 ; 0301-0449
    ISSN (online) 1432-1998
    ISSN 0301-0449
    DOI 10.1007/s00247-023-05638-1
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  9. Article ; Online: Neuroimaging findings and neurological manifestations in hospitalized COVID-19 patients: Impact of cancer and ventilatory support status.

    McCarthy, Lily / Khegai, Oleksandr / Goldstein, Jonathan / Belani, Puneet / Pawha, Puneet / Kihira, Shingo / Mathew, Brian / Gururangan, Kapil / Hao, Qing / Singh, Anuradha / Navis, Allison / Delman, Bradley N / Jette, Nathalie / Balchandani, Priti

    PloS one

    2023  Volume 18, Issue 3, Page(s) e0283614

    Abstract: Introduction: Coronavirus 2019 (COVID-19) is known to affect the central nervous system. Neurologic morbidity associated with COVID-19 is commonly attributed to sequelae of some combination of thrombotic and inflammatory processes. The aim of this ... ...

    Abstract Introduction: Coronavirus 2019 (COVID-19) is known to affect the central nervous system. Neurologic morbidity associated with COVID-19 is commonly attributed to sequelae of some combination of thrombotic and inflammatory processes. The aim of this retrospective observational study was to evaluate neuroimaging findings in hospitalized COVID-19 patients with neurological manifestations in cancer versus non-cancer patients, and in patients with versus without ventilatory support (with ventilatory support defined as including patients with intubation and noninvasive ventilation). Cancer patients are frequently in an immunocompromised or prothrombotic state with side effects from chemotherapy and radiation that may cause neurological issues and increase vulnerability to systemic illness. We wanted to determine whether neurological and/or neuroimaging findings differed between patients with and without cancer.
    Methods: Eighty adults (44 male, 36 female, 64.5 ±14 years) hospitalized in the Mount Sinai Health System in New York City between March 2020 and April 2021 with reverse-transcriptase polymerase chain reaction-confirmed COVID-19 underwent magnetic resonance imaging (MRI) during their admissions. The cohort consisted of four equal subgroups based on cancer and ventilatory support status. Clinical and imaging data were acquired and analyzed.
    Results: Neuroimaging findings included non-ischemic parenchymal T2/FLAIR signal hyperintensities (36.3%), acute/subacute infarcts (26.3%), chronic infarcts (25.0%), microhemorrhages (23.8%), chronic macrohemorrhages (10.0%), acute macrohemorrhages (7.5%), and encephalitis-like findings (7.5%). There were no significant differences in neuroimaging findings between cancer and non-cancer subgroups. Clinical neurological manifestations varied. The most common was encephalopathy (77.5%), followed by impaired responsiveness/coma (38.8%) and stroke (26.3%). There were significant differences between patients with versus without ventilatory support. Encephalopathy and impaired responsiveness/coma were more prevalent in patients with ventilatory support (p = 0.02). Focal weakness was more frequently seen in patients without ventilatory support (p = 0.01).
    Discussion: This study suggests COVID-19 is associated with neurological manifestations that may be visible with brain imaging techniques such as MRI. In our COVID-19 cohort, there was no association between cancer status and neuroimaging findings. Future studies might include more prospectively enrolled systematically characterized patients, allowing for more rigorous statistical analysis.
    MeSH term(s) Adult ; Humans ; Male ; Female ; COVID-19/complications ; COVID-19/diagnostic imaging ; Coma ; SARS-CoV-2 ; Neuroimaging/methods ; Stroke/etiology ; Neoplasms/complications ; Neoplasms/diagnostic imaging ; Neoplasms/therapy
    Language English
    Publishing date 2023-03-24
    Publishing country United States
    Document type Observational Study ; Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0283614
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  10. Article ; Online: Correction to: Dose length product to effective dose coefficients in children.

    Chu, Philip W / Kofler, Cameron / Mahendra, Malini / Wang, Yifei / Chu, Cameron A / Stewart, Carly / Delman, Bradley N / Haas, Brian / Lee, Choonsik / Bolch, Wesley E / Smith-Bindman, Rebecca

    Pediatric radiology

    2023  Volume 53, Issue 10, Page(s) 2165

    Language English
    Publishing date 2023-09-01
    Publishing country Germany
    Document type Published Erratum
    ZDB-ID 124459-0
    ISSN 1432-1998 ; 0301-0449
    ISSN (online) 1432-1998
    ISSN 0301-0449
    DOI 10.1007/s00247-023-05756-w
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