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Signal intensity patterns in health and disease: basics of abdominal magnetic resonance imaging in children. Pediatr Radiol 2022; 52:158-166. [PMID: 33837799 DOI: 10.1007/s00247-021-05071-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 02/10/2021] [Accepted: 03/22/2021] [Indexed: 10/21/2022]
Abstract
Magnetic resonance imaging (MRI) is playing an increasing role in pediatric abdominal imaging, especially in the evaluation of diffuse parenchymal disease where other imaging modalities might be less sensitive. While quantitative imaging is slowly being incorporated into clinical imaging, qualitative assessment of visceral signal intensity should be part of the routine clinical workflow of all radiologists. Based on their T1 and T2 weighting, the liver, spleen, kidneys and pancreas have characteristic signal intensity patterns with respect to one another and to skeletal muscle. It is important to recognize normal signal intensity patterns of viscera and their evolution with patient age to be able to identify age-related variations and accurately identify diffuse parenchymal disease. Knowledge of normal signal intensity patterns can also help identify ectopic locations of normal tissue such as splenic rests and splenosis. In this review, we discuss normal signal intensity patterns of upper abdominal viscera and their variations on commonly used sequences in pediatric abdominal MRI. We also review normal variations in the perinatal period. Knowledge of these patterns can help pediatric radiologists become more astute in their interpretation of diffuse parenchymal disease in the abdomen.
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Masselli G, Cozzi D, Ceccanti S, Laghi F, Giancotti A, Brunelli R. Fetal body MRI for fetal and perinatal management. Clin Radiol 2021; 76:708.e1-708.e8. [PMID: 34112509 DOI: 10.1016/j.crad.2021.05.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 05/05/2021] [Indexed: 12/19/2022]
Abstract
Fetal magnetic resonance imaging (MRI) has become a valuable adjunct to ultrasound (US) in diagnosing fetal abnormalities. This review is intended to highlight the contribution of MRI in parental counselling and perinatal treatment. A state-of-the-art fetal MRI protocol with experts of maternal-fetal medicine present in the MRI suite allows emphasis on patient-centred care and maximises therapeutic options.
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Affiliation(s)
- G Masselli
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy.
| | - D Cozzi
- Pediatric Surgery Unit, Sapienza University of Rome, Azienda Policlinico Umberto I, Rome, Italy
| | - S Ceccanti
- Pediatric Surgery Unit, Sapienza University of Rome, Azienda Policlinico Umberto I, Rome, Italy
| | - F Laghi
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, Rome, Italy
| | - A Giancotti
- Department of Gynecological, Obstetrical, and Urological Sciences, Sapienza University, Rome, Italy
| | - R Brunelli
- Department of Gynecological, Obstetrical, and Urological Sciences, Sapienza University, Rome, Italy
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Abstract
In utero diffusion magnetic resonance imaging (MRI) provides unique opportunities to noninvasively study the microstructure of tissue during fetal development. A wide range of developmental processes, such as the growth of white matter tracts in the brain, the maturation of placental villous trees, or the fibers in the fetal heart remain to be studied and understood in detail. Advances in fetal interventions and surgery furthermore increase the need for ever more precise antenatal diagnosis from fetal MRI. However, the specific properties of the in utero environment, such as fetal and maternal motion, increased field-of-view, tissue interfaces and safety considerations, are significant challenges for most MRI techniques, and particularly for diffusion. Recent years have seen major improvements, driven by the development of bespoke techniques adapted to these specific challenges in both acquisition and processing. Fetal diffusion MRI, an emerging research tool, is now adding valuable novel information for both research and clinical questions. This paper will highlight specific challenges, outline strategies to target them, and discuss two main applications: fetal brain connectomics and placental maturation.
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Value of Fetal MRI in the Era of Fetal Therapy for Management of Abnormalities Involving the Chest, Abdomen, or Pelvis. AJR Am J Roentgenol 2018. [DOI: 10.2214/ajr.17.18948] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Abstract
Fetal MRI is a level III diagnostic tool performed subsequently a level II prenatal ultrasound (US), in cases of inconclusive ultrasonographic diagnosis or when a further investigation is required to confirm or improve the diagnosis, to plan an appropriate pregnancy management. Fetal MRI plays an increasingly important role in the prenatal diagnosis of fetal neck, chest and abdominal malformations, even if its role has been amply demonstrated, especially, in the field of fetal CNS anomalies. Due to its multiparametricity and multiplanarity, MRI provides a detailed evaluation of the whole fetal respiratory, gastrointestinal and genitourinary systems, especially on T2-weighted (W) images, with a good tissue contrast resolution. In the evaluation of the digestive tract, T1-W sequences are very important in relation to the typical hyperintensity of the large intestine, due to the presence of meconium. The objective of this review is to focus on the application of fetal MRI in neck, chest and abdominal diseases.
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Faure A, Panait N, Panuel M, Alessandrini P, D'Ercole C, Chaumoitre K, Merrot T. Predicting postnatal renal function of prenatally detected posterior urethral valves using fetal diffusion-weighted magnetic resonance imaging with apparent diffusion coefficient determination. Prenat Diagn 2017; 37:666-672. [DOI: 10.1002/pd.5063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 03/29/2017] [Accepted: 04/21/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Alice Faure
- Aix-Marseille Université; Marseille France
- Paediatric Surgery Department; APHM, CHU Hopital Nord; Marseille France
| | - Nicoleta Panait
- Aix-Marseille Université; Marseille France
- Paediatric Surgery Department; APHM, CHU Hopital Nord; Marseille France
| | - Michel Panuel
- Aix-Marseille Université; Marseille France
- Medical Imaging Department; APHM, CHU Hopital Nord; Marseille France
| | - Pierre Alessandrini
- Aix-Marseille Université; Marseille France
- Paediatric Surgery Department; APHM, CHU Hopital Nord; Marseille France
| | - Claude D'Ercole
- Aix-Marseille Université; Marseille France
- Gynecologic & Obstetrical Department; APHM, CHU Hopital Nord; Marseille France
| | - Kathia Chaumoitre
- Aix-Marseille Université; Marseille France
- Medical Imaging Department; APHM, CHU Hopital Nord; Marseille France
| | - Thierry Merrot
- Aix-Marseille Université; Marseille France
- Paediatric Surgery Department; APHM, CHU Hopital Nord; Marseille France
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Gómez Huertas M, Culiañez Casas M, Molina García F, Carrillo Badillo M, Pastor Pons E. Complementary role of magnetic resonance imaging in the study of the fetal urinary system. RADIOLOGIA 2016. [DOI: 10.1016/j.rxeng.2016.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Gómez Huertas M, Culiañez Casas M, Molina García F, Carrillo Badillo M, Pastor Pons E. Papel complementario de la resonancia magnética en el estudio del sistema urinario fetal. RADIOLOGIA 2016; 58:101-10. [DOI: 10.1016/j.rx.2015.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Revised: 12/11/2015] [Accepted: 12/16/2015] [Indexed: 12/11/2022]
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Ye J, Kumar BS, Li XB, Li HM, Zhou YW, Liu LQ. Clinical applications of diffusion-weighted magnetic resonance imaging in diagnosis of renal lesions - a systematic review. Clin Physiol Funct Imaging 2015; 37:459-473. [PMID: 26648310 DOI: 10.1111/cpf.12313] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 09/21/2015] [Indexed: 01/07/2023]
Abstract
Diffusion-weighted magnetic resonance imaging (DW-MRI) is an established technique to detect the changes of the diffusion of water in biological tissues and reflect the pathophysiological process on the molecular level. It is a promising non-invasive imaging modality in detection of microstructural and functional changes in pathologies of kidney. To systematically review the research advancement of the DW-MRI in diagnosis of renal lesions, a systematic literature search was performed up to 8 October 2014 using the MEDLINE/PubMed and Embase databases for articles reporting on DW-MRI in diagnosis of renal lesions. Only articles with full data about DW-MRI application with potential implication in solving usually encountered clinical challenges about renal lesions were finally examined. The clinical application of DW-MRI allows a better understanding of some pathologic conditions of the kidney including renal insufficiency, renal artery stenosis, ureteral obstruction, foetal kidney disease, hydronephrosis and pyonephrosis. In addition, DW-MRI can also provide clinicians with the information of function evaluation of renal allograft and curative effect assessment of renal tumour. In summary, performance of renal DW-MRI, presuming that measurements are high quality, will further boost this modality, particularly for early detection of diffusion renal conditions, as well as more accurate characterization of renal lesions.
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Affiliation(s)
- Jing Ye
- Department of Imaging, Northern Jiangsu People's Hospital, Yangzhou, China
| | | | - Xiao-Bo Li
- Department of Neurology, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Hong-Mei Li
- Department of Imaging, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Ying-Wen Zhou
- Department of Imaging, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Li-Qin Liu
- Department of Oncology, Northern Jiangsu People's Hospital, Yangzhou, China
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Prenatal Diagnosis of Renal Failure by Fetal Biparametric Magnetic Resonance Imaging. JOURNAL OF FETAL MEDICINE 2015. [DOI: 10.1007/s40556-015-0062-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Fetal Megacystis: Etiologies, Management, and Outcome According to the Trimester. Urology 2014; 84:185-90. [DOI: 10.1016/j.urology.2014.02.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 02/13/2014] [Accepted: 02/15/2014] [Indexed: 11/23/2022]
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Pico H, Dabadie A, Bourliere-Najean B, Philip N, Capelle M, Aschero A, Quarello E, Guys JM, Hery G, Petit P, Gorincour G. Contribution of the foetal uro-MRI in the prenatal diagnosis of uronephropathies. Diagn Interv Imaging 2014; 95:573-8. [DOI: 10.1016/j.diii.2014.02.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
Applications of diffusion-weighted (DW) magnetic resonance (MR) imaging outside the brain have gained increasing importance in recent years. Owing to technical improvements in MR imaging units and faster sequences, the need for noninvasive imaging without contrast medium administration, mainly in patients with renal insufficiency, can be met successfully by applying this technique. DW MR imaging is quantified by the apparent diffusion coefficient (ADC), which provides information on diffusion and perfusion simultaneously. By using a biexponential fitting process of the DW MR imaging data, these two entities can be separated, because this type of fitting process can serve as an estimate of both the perfusion fraction and the true diffusion coefficient. DW MR imaging can be applied for functional evaluation of the kidneys in patients with acute or chronic renal failure. Impairment of renal function is accompanied by a decreased ADC. Acute ureteral obstruction leads to perfusion and diffusion changes in the affected kidney, and renal artery stenosis results in a decreased ADC. In patients with pyelonephritis, diffuse or focal changes in signal intensity are seen on the high-b-value images, with increased signal intensity corresponding to low signal intensity on the ADC map. The feasibility and reproducibility of DW MR imaging in patients with transplanted kidneys have already been demonstrated, and initial results seem to be promising for the assessment of allograft deterioration. Overall, performance of renal DW MR imaging, presuming that measurements are of high quality, will further boost this modality, particularly for early detection of diffuse renal conditions, as well as more accurate characterization of focal renal lesions.
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Affiliation(s)
- Harriet C Thoeny
- Department of Radiology, Neuroradiology and Nuclear Medicine, University of Bern, Inselspital, Freiburgstrasse 10, CH-3010 Bern, Switzerland.
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Triulzi F, Manganaro L, Volpe P. Fetal magnetic resonance imaging: indications, study protocols and safety. Radiol Med 2011; 116:337-50. [DOI: 10.1007/s11547-011-0633-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Accepted: 09/02/2010] [Indexed: 12/17/2022]
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Lee W, Krisko A, Shetty A, Yeo L, Hassan SS, Gotsch F, Mody S, Gonçalves LF, Romero R. Non-invasive fetal lung assessment using diffusion-weighted imaging. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2009; 34:673-7. [PMID: 19859908 PMCID: PMC2789899 DOI: 10.1002/uog.7446] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/03/2009] [Indexed: 05/28/2023]
Abstract
OBJECTIVES The main goal was to develop a reproducible method for estimating the diffusion of water in human fetal lung tissue using diffusion-weighted imaging (DWI). A secondary objective was to determine the relationship of the apparent diffusion coefficients (ADCs) in the fetal lung to menstrual age and total lung volume. METHODS Normal pregnant volunteers were scanned on a 1.5-Tesla (T) magnetic resonance imaging (MRI) system. The MRI system was equipped with 40-mT/m gradients (slew rate 200 T/m/s, rise time 0.2 ms). A six-channel body array coil was used for signal reception. Single-shot DWI utilized TE/TR 125/3400 ms, slice thickness 4 mm, field of view 280 mm x 280 mm, interslice gap 0.8 mm and a matrix of 128 x 128. The voxel size was 2.5 mm x 2.5 mm x 4.0 mm. Two b-values (0 and 1000) were chosen along three orthogonal directions. ADC maps were created using assigned b-values. Simple linear regression was performed with Pearson correlation coefficient. Interexaminer and intraexaminer bias, and 95% limits of agreement (LOA) were determined using Bland-Altman plots. RESULTS Forty-seven scans were performed at a mean +/- SD of 29.2 +/- 4.5 weeks. The median coefficient of variation for ADC was 5.6% (interquartile range, 4.0-8.1%). No differences in ADC values were found between right and left lungs. Normally distributed ADC measurements were not significantly correlated with either total lung volume (r(2) = 0.0001, P = 0.94) or menstrual age (r(2) = 0.003, P = 0.70). The mean ADC value was 1.75 (95% CI, 1.63-1.86). Mean +/- SD intraexaminer bias was -0.15 +/- 2.3 (95% LOA, -4.7 to + 4.4) and interexaminer bias was 2.2 +/- 3.5 (95% LOA, -4.7 to + 9.1). CONCLUSIONS Our findings suggest that ADC measurements of the fetal lung are reproducible between blinded examiners and are independent of menstrual age, as well as lung volume.
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Affiliation(s)
- W Lee
- Division of Fetal Imaging, Department of Obstetrics and Gynecology, William Beaumont Hospital, Royal Oak, MI, USA.
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Manganaro L, Francioso A, Savelli S, Tomei A, Fierro F, Di Maurizio M, Coratella F, Perrone A, Ballesio L, Giancotti A, Porfiri L, Marini M. Fetal MRI with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) assessment in the evaluation of renal development: preliminary experience in normal kidneys. Radiol Med 2009; 114:403-13. [DOI: 10.1007/s11547-009-0382-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Accepted: 10/06/2008] [Indexed: 01/19/2023]
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Affiliation(s)
- Catherine Garel
- Service de Radiologie Pédiatrique, Hôpital d'Enfants Armand-Trousseau, 26-28 Avenue du Dr Arnold Netter, 75571, Paris Cedex 12, France.
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Magnetic resonance imaging diagnosis of severe fetal renal anomalies. Am J Obstet Gynecol 2008; 198:328.e1-5. [PMID: 18036507 DOI: 10.1016/j.ajog.2007.09.032] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Revised: 06/15/2007] [Accepted: 09/19/2007] [Indexed: 11/20/2022]
Abstract
OBJECTIVE The purpose of this study was to describe magnetic resonance imaging (MRI) findings in fetuses with severe renal anomalies. STUDY DESIGN This was a case-control study that compared MRI findings in fetuses with suspected severe renal anomalies with gestational age-matched control fetuses. MRI was performed with T2-weighted single-shot fast-spin echo sequences. Each MRI was reviewed by an investigator who was blinded to clinical information. RESULTS There were 2 cases of bilateral renal agenesis, 2 cases if bilateral multicystic dysplastic kidney disease, 2 cases if unilateral renal agenesis and contralateral multicystic dysplastic kidney disease, 2 cases if polycystic kidney disease, and 2 cases of early membrane rupture/normal kidneys. Fetuses with lethal renal anomalies had a characteristic bladder appearance (signal void [dark]), whereas control fetuses had bright signal in both bladder and renal pelvis (P < .001). Both cases of early membrane rupture/normal kidneys had bright bladder signal, but 1 case did not have bright signal in the renal pelvis. CONCLUSION Fetuses with lethal renal anomalies had signal void in the bladder region on MRI.
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Garel C. Fetal MRI: what is the future? ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2008; 31:123-128. [PMID: 18254129 DOI: 10.1002/uog.5249] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
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Current World Literature. Curr Opin Obstet Gynecol 2007; 19:596-605. [DOI: 10.1097/gco.0b013e3282f37e31] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Savelli S, Di Maurizio M, Perrone A, Tesei J, Francioso A, Angeletti M, La Barbera L, Ballesio L, de Felice C, Porfiri LM, Manganaro L. MRI with diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) assessment in the evaluation of normal and abnormal fetal kidneys: preliminary experience. Prenat Diagn 2007; 27:1104-11. [PMID: 17849498 DOI: 10.1002/pd.1839] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To investigate apparent diffusion coefficient (ADC) mapping with the measurement of renal tissue ADC value of normal and pathological fetal kidneys at various gestational ages (GAs). METHODS Fifty pregnant women underwent magnetic resonance images (MRI) after ultrasound (US) for suspected fetal genitourinary disorders (16) or for suspected disorders in other organs (34). A multiplanar study of urinary system was obtained by using conventional T2-weighted sequences and echo planar imaging (EPI); Diffusion-weighted images and ADC maps were evaluated. The renal tissue ADC value was measured for all normal and abnormal fetuses and related to GA. RESULTS MRI confirmed urinary anomalies in 15 fetuses [2 renal developmental variants, 2 nephropathies, 4 multicystic dysplastic kidneys (MCDK), 7 renal tract dilatations] and detected normal kidneys in the remaining 35 fetuses. Normal renal parenchyma showed bright signal on diffusion-weighted images with ADC values ranging from 1,065 to 1,327 microm(2)/s with a tendency to decrease over GA. A pathological ADC was detected in cases of bilateral MCDK, huge dilatations and in cases of nephropathies. CONCLUSION Diffusion-weighted imaging (DWI) with ADC mapping can be used in the evaluation of fetal renal parenchyma and may become a tool of assessing function of the fetal kidney by means of measurement of renal tissue ADC values.
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Affiliation(s)
- Sara Savelli
- UMBERTO I hospital-LA SAPIENZA University of Rome, Radiological Sciences, Italy.
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Brasseur-Daudruy M, Ickowicz V, Eurin D. IRM fœtale : indications, limites et dangers. ACTA ACUST UNITED AC 2007; 35:678-83. [PMID: 17602848 DOI: 10.1016/j.gyobfe.2007.05.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Accepted: 05/25/2007] [Indexed: 11/26/2022]
Abstract
Although prenatal sonography remains the primary imaging method for screening fetal anomalies, fetal MRI with ultrafast imaging technique is a complementary imaging method as soon as the second trimester. It allows better tissue contrast images than does US, a large field of view of the foetus and is not limited by large maternal body habitus and oligohydramnios, without any risk for the foetus. In the future, the development of new techniques (diffusion-weighted imaging, proton MR spectroscopy) and faster sequences will make it possible to widen the indications i.e. cardiac, functional renal and cerebral imaging.
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Affiliation(s)
- M Brasseur-Daudruy
- Service de Radiopédiatrie, Centre Hospitalier Universitaire de Rouen, 1 Rue de Germont, 76031 Rouen cedex, France.
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