Use of nonechoplanar diffusionweighted mr imaging for. We examine the clinical impetus for wholebody diffusionweighted mri and discuss how to implement the technique with clinical mri systems. C, at this location, increased dw signal intensity is shown on the transverse nonepi dwi sequence, indicative of cholesteatoma. Hence, increasingly the dwi sequence mri can be used to distinguish. Artifacts related to airbone interface in the mastoid region may represent a relevant limitation to the utilization of echoplanar diffusionweighted imaging. Over the past decade, numerous imaging studies have been performed looking into detection of cholesteatomas, investigating both echo planar imaging epi and nonepi dwi sequences. Since it was first described in 2006 for the detection of cholesteatoma 1, 2, nonechoplanar diffusion weighted magnetic resonance imaging dwi has now firmly established its role as the imaging modality of choice in detecting postoperative cholesteatoma 37. There are multiple intrinsic problems to epi 6, leaving ample room for other fast imaging techniques. Can diffusionweighted mri without breathholding be used. As epi is a multiecho gre technique, a nonechoplanar technique should be a. Heavily diffusionweighted b 1100 or 1200 smm 2 axial images were obtained with singleshot echoplanar technique in 93 patients with pathologically confirmed various intracranial tumors and tumorlike conditions with diffusion gradient perpendicular to the images. Diffusion mri in the heart, however, has proven technically challenging because of the intrinsic nonrigid deformation during the cardiac cycle, displacement of the myocardium due to re. Pdf nonechoplanar diffusionweighted imaging of middle ear. Potential value of nonechoplanar diffusionweighted.
Two patients 68 and 71 years, both female with sight threatening, active graves orbitopathy but low clinical activity score underwent mri scans before and after intravenous corticosteroid treatment. Other sequences acquire one kspace line at each phase encoding step. We assess diffusionweighted mr images in the differential diagnosis of intracranial brain tumors and tumorlike conditions. As shown on figures 1a to 1e, at ct, the patient with postmastoidectomy residual cholesteatoma presents a mass with soft tissue density obstructing the surgical cavity which, at magnetic resonance imaging mri, demonstrated diffusion restriction at non echoplanar imaging. Nonepi pulse sequences for diffusion mri oxford medicine. Pdf nonechoplanar diffusionweighted imaging of middle. In this case, each rf excitation is followed by a train of gradient echoes with different spatial encoding. The epi sequence can be collected as a blipped or nonblipped technique.
Singleshot echoplanar diffusionweighted mr imaging at. Nonechoplanar diffusion weighted magnetic resonance imaging dwi has established itself as the modality of choice in detecting and localising postoperative middle ear cleft cholesteatoma. Transverse spinecho t1weighted image a shows a lesion of low signal intensity, which is shown as a hyperintense lesion on the transverse turbo spinecho t2weighted image b. This switching or reversal may also be done in a sinusoidal.
Pdf firstly, the ct imaging in cholesteatoma may not be diagnostic. Nonechoplanar diffusionweighted magnetic resonance imaging is superior to routine echoplanar diffusionweighted magnetic resonance imaging as it minimises susceptibility artefacts. In diffusionweighted magnetic resonance imaging dwi, the intensity of the acquired. Diffusionweighted echoplanar mri of the brain with calculated adcs. Diagnostic capacity of nonecho planar diffusionweighted. Advances in gradient and digital data acquisition technology have made it possible to obtain individual mr slices in the time frame of 50100 msec, thus minimizing the effects of patient motion. Mapping eddy current induced fields for the correction of diffusionweighted echo planar images, magnetic resonance imaging. Also it will address the use of advanced mri techniques such as dcemri and diffusionweighted mri and the potential of mri for guidance of brachytherapy and externalbeam radiotherapy. Conclusion nonechoplanar imaging diffusionweighted magnetic resonance imaging is a high sensitivity imaging test for detecting cholesteatoma, for both primary diagnosis and for recurrent cases. To evaluate non echoplanar diffusion weighted magnetic resonance imaging nonep dw mri at 9 months after primary surgery to rule out residual cholesteatoma in patients scheduled before secondlooksurgical exploration. Nonechoplanar diffusion weighted mri nedwi combined with t2 weighted imaging acquisition using haste halffourier acquisition singleshot turbo spinecho has been shown to be more accurate in diagnosing cholesteatoma within the postoperative ear than the standard echoplanar diffusion weighted imaging epdwi routinely used to identify. When the echo planar imaging acquisition strategy is used, the complete image is formed from a single data sample all kspace. Introduction and aims the aim of this study was to determine the certainty of nonechoplanar imaging diffusionweighted magnetic resonance imaging nonepi dw mri in the diagnosis of primary and.
Technical aspects of mr diffusion imaging of the body. Diffusionweighted mri dwmri is a powerful tool for the detection of cholesteatoma. Nonepi dwi is a promising alternative to secondlook surgery for the. Epi echo planar imaging is one of the early magnetic resonance imaging sequences also known as intascan, used in applications like diffusion, perfusion, and functional magnetic resonance imaging. To investigate the diagnostic value of nonecho planar diffusionweighted magnetic resonance imaging dwmri for primary and recurrentresidual postoperative cholesteatoma in adults. This study retrospectively compares diagnostic performance of 1. Imaging provide, noninvasively, significant structural and functional information in a. A total of 46 spinal examinations were included in the 1. Mapping fiber orientation spectra in cerebral white matter.
Schlaier j, bretschneider t, schuierer g, feuerbach s. Objectiveshypothesis to describe the accuracy of nonecho. Whereas this fast sequence may be sufficient to screen for residual cholesteatoma in canal. Use of nonechoplanar diffusionweighted mr imaging for the. Our aim was to assess the usefulness of magnetic resonance imaging mri with spinecho echoplanar diffusionweighted sequences seepidwi in the study of primary and secondary softtissue tumours by correlating the results of imaging and histology.
Non echo planar, diffusionweighted magnetic resonance imaging periodically rotated overlapping parallel lines with enhanced reconstruction sequence compared with echo planar imaging for the detection of middleear cholesteatoma. Non echo planar, diffusionweighted magnetic resonance imaging periodically rotated overlapping parallel lines with enhanced reconstruction sequence compared with echo planar imaging for the detection of middleear cholesteatoma volume 125 issue 4 a v kasbekar, d j scoffings, b kenway, j cross, n donnelly, s w k lloyd, d moffat, p r axon. The aim of this study was to analyze the role of nonechoplanar imaging nonepibased diffusionweighted dw magnetic resonance imaging mri for the detection of residual cholesteatoma after. Contemporary nonechoplanar diffusionweighted imaging of. Objectiveto investigate the diagnostic value of nonecho planar diffusionweighted magnetic resonance imaging dwmri for primary and. Nonechoplanar diffusion weighted imaging in the detection. The diffusion weighted epi sequence is very similar to a spin echo sequence. Nonechoplanar diffusion weighted magnetic resonance imaging dwi has established itself as the modality of choice in detecting and. Weighted diffusion weighted mri is capable of obtaining all sorts of information. Recently, non echo planar diffusion weighted mr imaging non ep dw mri has gained much attention due to its short acquisition time and high sensitivity and specificity for detecting even small cholesteatomas of 2 3 mm in size 1.
The diagnostic accuracy of nonechoplanar diffusion. It has superseded ct, echoplanar dwi and delayed contrast mri by virtue of its superior diagnostic performance 38. Cholesteatoma imaging using modified echoplanar diffusion. Nonecho planar diffusionweighted imaging in cholesteatoma radiol bras. Characterization of and correction for eddy current artifacts in echo planar diffusion imaging. Fast and ultrafast nonechoplanar mr imaging techniques. Nonechoplanar diffusionweighted mri in cholesteatoma. Detection of postoperative residual cholesteatoma with non. Rapid echo planar imaging and highperformance mri gradient systems create fastswitching magnetic fields that can stimulate muscle and nerve tissues produced by either changing the electrical resistance or the potential of the excitation.
The problem is that diffusion measurements can be particularly vulnerable to. Average artefacts scores were evaluated and the lesion size measured as a distortion indicator. Non echo planar, diffusionweighted magnetic resonance. The difference lies in a unique gradient activation at different amplitudes prior. The aim of this study was to analyze the role of nonechoplanar imaging nonepibased diffusionweighted dw magnetic resonance imaging mri for the detection of residual cholesteatoma after canal wallup mastoidectomy before eventual secondlook surgery. To qualitatively and quantitatively evaluate image quality and compare the diagnostic value of nonechoplanar diffusionweighted imaging dwi based on turbo spinecho tse and echoplanar imaging epi, to distinguish rnpc from postchemoradiation fibrosis. Turbo spin non echoplanar diffusion weighted mri for. Texture analysis of multishot echoplanar diffusionweighted imaging in head and neck squamous cell carcinoma. The diagnostic accuracy of non echo planar diffusion weighted imaging in the detection of residual andor recurrent cholesteatoma of the temporal bone. Generically, this acquisition mode is known as echoplanar imaging epi.
Pdf to retrospectively compare nonechoplanar nonep. Nonechoplanar diffusion weighted imaging in the detection of post. The purpose of this study was to compare the value of respirationtriggered diffusionweighted dw singleshot echoplanar mri epi and five variants of t2weighted turbo spinecho tse sequences in the diagnosis of hepatic metastasis. The purpose of this study was to determine the diagnostic accuracy of haste dwi for the detection of incipient cholesteatoma in highrisk retraction pockets. Diffusion mri provides unique information on the structure, organization, and integrity of the myocardium without the need for exogenous contrast agents.
Negative predictive value of nonechoplanar diffusion. Nagai n, tono t, matsuda k, toyama k, kawano h, kodama t 2008 value of non echoplanar diffusionweighted magnetic resonance imaging in the detection of middle ear cholesteatomea. Nonechoplanar dwi mr imaging including the haste sequence has been shown to be highly sensitive and specific for large cholesteatomas. Echoplanar imaging epi questions and answers in mri. Characterization of and correction for eddy current. Echoplanar imaging cspiral dradial each method has its own. People with nonmricompatible implants people with metal pieces near vital organs.
Peripheral enhancement is observed at delayed phase 45 minutes after. The diagnostic accuracy of nonechoplanar diffusionweighted imaging in the detection of residual andor recurrent cholesteatoma of the temporal bone m. To compare the apparent diffusion coefficient adc value using singleshot echoplanar imaging sequences at 3t and 1. Promising new nonechoplanar diffusionweighted imaging techniques used in the diagnosis of cholesteatoma are presented, with emphasis. Singleshot echo planar imaging ssepi is the most common data collection method for diffusion weighted mri primarily because it is relatively immune to the undesired phase caused by motion during diffusion weighting, and secondarily because it is fast, allowing collection of data with many different diffusion weightings in a reasonable scan time. Pdf using nonechoplanar diffusionweighted mri to assess. New nonechoplanar diffusionweighted magnetic resonance imaging mri techniques, without intravenous contrast, are capable of differentiating cholesteatoma from inflammatory tissue, cholesterol. Texture analysis of multishot echoplanar diffusion. Nonecho planar diffusion weighted mri nedwi mri is accurate in detecting cholesteatoma in the postoperative ear but the effect on surgical decisionmaking in the setting of revision mastoid surgery using surgical histopathology as the gold standard has not been investigated.
Pdf the diagnostic accuracy of nonechoplanar diffusion. To add this web app to the home screen open the browser option menu and tap on add to homescreen. The exclusion criteria were a pathological diagnosis of nasopharyngeal scc or nonscc, b unavailable pretreatment mri or 18 ffdg petct and c. Another scheme which is sometimes used, especially in brain scanning or where images are needed very rapidly, is called echoplanar imaging epi. Recently, nonecho planar diffusionweighted mr imaging nonep dw mri has gained much attention due to its short acquisition time and high sensitivity and specificity for detecting even small cholesteatomas of 2 3 mm in size 1. Protocol optimization and choice of sequences shahid m. There are apparently no effects on the conduction of impulses in the nerve fiber up to field strength of 0.
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