Papers by Jeremy Lasbleiz
Poster: "ECR 2012 / B-1011 / An ontology of magnetic resonance imaging sequences" by: &... more Poster: "ECR 2012 / B-1011 / An ontology of magnetic resonance imaging sequences" by: "J. Lasbleiz, A. Burgun, R. Duvauferrier, H. Saint-Jalmes; Rennes/FR"
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Magnetic Resonance Materials in Physics, Biology and Medicine, 2021
MRI is a reliable and accurate technique to characterize rheumatoid arthritis. The aim of this st... more MRI is a reliable and accurate technique to characterize rheumatoid arthritis. The aim of this study was to provide voxel-by-voxel 3D maps of the proton density fat fraction (PDFF), the T1 of water (T1W), the T1 of fat (T1F), the T2* of water (T2*W), the T2* of fat (T2*F) in the wrist bone marrow. The experiments were conducted on 14 healthy volunteers (mean age: 24 ± 4). The data were acquired at 1.5 T using two optimized four-echo 3D 1.2 × 1.2 × 1.2 mm3-isotropic spoiled gradient sequences. A repeatability study was carried out. The measurements were done using a homemade parametric viewer software. The inter-volunteer results were, on average: PDFF = 86 ± 3%, T1W = 441 ± 113 ms, T1F = 245 ± 19 ms, T2*W = 6 ± 1 ms and T2*F = 16 ± 3 ms. The coefficients of variation were for fat based biomarkers CVPDFF < 5%, CVT1F < 15% and CVT2*F < 10% in the repeatability study. The protocol and quantification tool proposed in this study provide high-resolution voxel-by-voxel 3D maps of five biomarkers in the wrist in less than 4 min of acquisition.
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Journal de Radiologie
To evaluate the contribution of diffusion weighted MR imaging in malignant spine pathology. Mater... more To evaluate the contribution of diffusion weighted MR imaging in malignant spine pathology. Materials and methods. Between February 2004 and January 2005, 49 patients (43 to 86 years old) were included. Three groups were made: osteoporotic collapses (n = 13), malignant collapses (n = 15) and malignant spine lesions (n = 21). The MRI (Symphony 1.5T) allowed SENSE imaging. After conventional MRI examination (T1, T2 fat sat, T1 with Gadolinium), all patients underwent diffusion weighted imaging (Spin Echo) with variable b values: 0, 250, 500, 750 and 1000. The diffusion sequence lasted 2 min 29 s. The Apparent Diffusion Coefficient (ADC) was calculated automatically. The analysis was qualitative (signal study b = 1,000 mm2/s) and quantitative (ADC measurement). The image quality was good except for some cervical examinations. Qualitative analysis did not show a difference between benign and malignant lesions. Quantitative results are: malignant spine lesion (mean ADC = 0.826 10-3 s/mm2...
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Journal de radiologie, 2005
The authors report a case of periosteal cavernous hemangioma of the distal humeral. They describe... more The authors report a case of periosteal cavernous hemangioma of the distal humeral. They describe the imaging findings of hemangiomas of long tubular bones and discuss their differential diagnosis.
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Journal de Radiologie, 2006
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Journal de Radiologie, 2006
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Clinical Imaging, 2006
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Clinical Imaging, 2007
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Poster: "ECR 2012 / C-0520 / Interest of shoulder sonography in the arthroscopic rotator cuf... more Poster: "ECR 2012 / C-0520 / Interest of shoulder sonography in the arthroscopic rotator cuff postoperative evaluation" by: "J. Lasbleiz, T. Benkalfate, J. Jan; Rennes/FR"
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Magnetic Resonance Imaging, 2017
Bone marrow is found either as red bone marrow, which mainly contains haematopoietic cells, or ye... more Bone marrow is found either as red bone marrow, which mainly contains haematopoietic cells, or yellow bone marrow, which mainly contains adipocytes. In adults, red bone marrow is principally located in the axial skeleton. A recent study has introduced a method to simultaneously estimate the fat fraction (FF), the T1 and T2* relaxation times of water (T1w, T2*w) and fat (T1f and T2*f) in the vertebral bone marrow. The aim of the current study was to measure FF, T1w, T1f, T2*w and T2*f in five sites of bone marrow, and to assess the presence of regional variations. MRI experiments were performed at 1.5T on five healthy volunteers (31.6±15.6years) using a prototype chemical-shift-encoded 3D multi-gradient-echo sequence (VIBE) acquired with two flip angles. Acquisitions were performed in the shoulders, lumbar spine and pelvis, with acquisition times of &amp;amp;amp;amp;lt;25seconds per sequence. Signal intensities of magnitude images of the individual echoes were used to fit the signal and compute FF, T1w, T1f, T2*w and T2*f in the humerus, sternum, vertebra, ilium and femur. Regional variations of fat fraction and relaxation times were observed in these sites, with higher fat fraction and longer T1w in the epiphyses of long bones. A high correlation between FF and T1w was measured in these bones (R=0.84 in the humerus and R=0.84 in the femur). In most sites, there was a significant difference between water and fat relaxation times, attesting the relevance of measuring these parameters separately. The method proposed in the current study allowed for measurements of FF, T1w, T1f, T2*w and T2*f in five sites of bone marrow. Regional variations of these parameters were observed and a strong negative correlation between the T1 of water and the fat fraction in bones with high fat fractions was found.
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Magnetic Resonance Imaging
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Journal of magnetic resonance imaging : JMRI, Jan 8, 2018
A limited number of studies have used the intravoxel incoherent motion (IVIM) approach on bone ma... more A limited number of studies have used the intravoxel incoherent motion (IVIM) approach on bone marrow. In none of the previous studies were the effects of fat suppression on the IVIM parameters investigated. To measure the water diffusion coefficient and the perfusion fraction in vertebral bone marrow using IVIM with multishot, readout-segmented (RESOLVE) echo-planar imaging and to assess the effects of different fat suppression techniques on the measurement of the IVIM parameters. Prospective. Six healthy volunteers (24.2 ± 4.3 years). 1.5T, RESOLVE. Four experiments were performed: 1) RESOLVE imaging without fat suppression, 2) with fat saturation (FS), 3) with spectral attenuated inversion recovery (SPAIR), and 4) with short-tau inversion recovery (STIR). The water diffusion coefficient D, pseudo-diffusion coefficient D*, and the perfusion fraction f were assessed in the vertebral bodies of the lumbar vertebrae. One-way repeated-measures analysis of variance (ANOVA) followed by B...
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Obstetrics & Gynecology
Severe separation of the pubic symphysis is a rare delivery complication. Facing this pathology, ... more Severe separation of the pubic symphysis is a rare delivery complication. Facing this pathology, we decided to study a new elastic band device. To evaluate the elastic band device, clinical (pain-rated) and imaging (magnetic resonance imaging and radiography) evaluations with and without the device were performed. The elastic band device is a European Conformity-certified medical device, which is made of neoprene straps, that reduces the mobility of the pelvis and the use of the internal rotator muscles. Once the elastic band device was in place, on postpartum day 1, radiography showed a decrease of the pubic width from 41 to 12 mm. Furthermore, pain decreased from 10 of 10 to 2 of 10 in 2 days, allowing the patient to ambulate and avoid surgery. After 1 month, the pubic width (6 mm) and anatomy were recovered but minor pain was still present with hip rotatory movements. The elastic band device was worn 24 hours a day from postpartum days 1-90 and 12 hours a day from postpartum days 90 to 150; afterward, the patient returned to normal life without the elastic band device. Use of an elastic band device was associated with a reduction of the pubic width and pain associated after obstetric pubic symphysis separation.
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J Radiol, 2006
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Journal of magnetic resonance imaging : JMRI, Sep 26, 2016
To assess the feasibility of measuring the fat fraction, T1 and T2 * relaxation times of water an... more To assess the feasibility of measuring the fat fraction, T1 and T2 * relaxation times of water and fat signals in vertebral bone marrow using breath-hold magnetic resonance imaging (MRI) gradient echo images of the spine. MRI experiments were performed at 1.5T on eight healthy volunteers (35.1 ± 15.7 years, five men and three women) using two sagittal four-echo 3D gradient echo volumetric interpolated breath-hold examination (VIBE Dixon) sequences acquired at two different flip angles (5° and 15°). The water/fat decomposition was performed in the vertebral bodies of L1 to L5 by fitting the signal to a function that depends on the echo time and the flip angle to calculate the fat fraction (FF) and T1 and T2 * relaxation times of water and fat signals. Repeatability was assessed by scanning one volunteer six times. The mean fat fraction over L1 to L5 was 33 ± 8%. The mean T1 and T2 * of water and fat signals were respectively T1w = 701 ± 151 msec, T2 *w = 13.7 ± 2.9 msec, T1f = 334 ± ...
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Http Www Theses Fr, Dec 19, 2013
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Journal de Radiologie, 2004
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PURPOSE/AIM Adamantinomas are rare malignancies most frequently involving the tibia. Benign lesio... more PURPOSE/AIM Adamantinomas are rare malignancies most frequently involving the tibia. Benign lesions like fibrous and osteofibrous dysplasia can mimic an adamantinoma radiographically and pathologically. An aggressive malignancy sharing some the same pathological features—adamantinoma-like Ewing sarcoma—has also been described. The purpose of this exhibit is to illustrate and review key imaging and pathologic distinctions among these entities. CONTENT ORGANIZATION Characteristic multi-modality imaging findings of the following lesions will be illustrated: Fibrous Dysplasia Osteofibrous Dysplasia Adamantinoma Adamantinoma-like Ewing Sarcoma Ewing Sarcoma Gross pathologic and histologic distinctions between the above entities will be illustrated and theories relating to their origin described. Differences in the management of the aforementioned entities will be detailed. SUMMARY After viewing this exhibit, the attendee will: Describe the characteristic imaging and pathologic appearance...
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Journal de Radiologie, 2005
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Revue De Chirurgie Orthopedique Et Traumatologique, Oct 29, 2012
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Papers by Jeremy Lasbleiz