MRI Artifacts This presentation is available at: Zhuo, J. et al. Radiographics 2006;26:275-297, AAPM/RSNA.

Slides:

Advertisements

Similar presentations

MRI Phillip W Patton, Ph.D..

Advertisements

In Chan Song, Ph.D. Seoul National University Hospital

Chapter 14: Artifacts Mark D. Herbst, MD, PhD. Artifact Something on the image that does not represent something in the patient –Many causes Equipment.

Chemical Shift To do with the different electron environments of protons Results in a shift of resonant frequency which affects the image e.g. fat (CH.

Noll Spin-Warp Imaging For each RF pulse:For each RF pulse: –Frequency encoding is performed in one direction –A single phase encoding value is obtained.

Functional Brain Signal Processing: EEG & fMRI Lesson 12 Kaushik Majumdar Indian Statistical Institute Bangalore Center M.Tech.

Diffusion Tensor MRI And Fiber Tacking Presented By: Eng. Inas Yassine.

Compressed Sensing for Chemical Shift-Based Water-Fat Separation Doneva M., Bornert P., Eggers H., Mertins A., Pauly J., and Lustig M., Magnetic Resonance.

MRI Image Formation Karla Miller FMRIB Physics Group.

BME Medical Imaging Applications Part 2: INTRODUCTION TO MRI Lecture 2 Basics of Magnetic Resonance Imaging Feb. 23, 2005 James D. Christensen, Ph.D.

MR Compatibility Torques Artifacts Not Compatible Yes Yes MR Safe No

BIOE 220/RAD 220 REVIEW SESSION 6 March 5, What We’ll Cover Today General questions? Spinal cord anatomy review Fat in images T2* vs T2 decay Review.

Magnetic Resonance Imaging

Basic MRI Chapter 1 Lecture. Introduction MRI uses radio waves and a magnetic field to make images MRI uses radio waves and a magnetic field to make images.

DTI Acquisition Guide Donald Brien February 2016.

Artifacts and Suppression Techniques

BOLD functional MRI Magnetic properties of oxyhemoglobin and deoxyhemoglobin L. Pauling and C. Coryell, PNAS USA 22: (1936) BOLD effects in vivo.

MRI OF PROTHETIC IMPLANTS IN MSK

MRI Artifacts Ray Ballinger, MD, PhD

A: Chemical shift artifact (arrows) on T1-weighted gradient echo scan in right ovarian dermoid cyst. This finding is the white on black line that occurs.

Sagittal MR images of the knee showing meniscal tear

University of Ottawa Diagnostic Radiology OSCE April 12th, 2004

Magnetic Resonance Imaging

Figure 1 Imaging of a painful knee using radiography and MRI

Sunday Case of the Day Category Physics Question:

Parallel Imaging Artifacts in Body Magnetic Resonance Imaging

Sunday Case of the Day Physics (Case 1: MR)

MR images and plain radiograph of an 82-year-old woman who had compression fractures and osteonecrosis at the L3 vertebral body. MR images and plain radiograph.

Radiology images of surgical conditions/congenital anomalies

Axial magnetic resonance (MR) imaging

A and B, Sagittal (A) and axial (B) fast spin-echo images of the cervical spine before treatment demonstrate diffuse increase in signal intensity (arrows)

Traumatic neuropathy. Traumatic neuropathy. A, Sagittal oblique plane T1-weighted image (560/10/2), obtained at the level of the piriformis muscle (asterisk),

Case 2. Case 2. A 66-year-old man who received epidural anesthesia and underwent MR imaging 2 days (A and B), 2 months (C and D), and 5 months (E and F)

Acute osteopenic compression fracture of the L1 vertebral body simulating metastasis. Acute osteopenic compression fracture of the L1 vertebral body simulating.

A–D, MR images of an 83-year-old man who was diagnosed with osteonecrosis at the L1 vertebral body. A–D, MR images of an 83-year-old man who was diagnosed.

Without fat suppression techniques, fat and fluid both have a high-signal intensity on fluid-sensitive fast spin echo. This adult patient with a history.

MRI ARTEFACTS PG Student : Dr Aditi Shah PG Guide: Dr Rajendra Chavan

Analysis of Dynamic Brain Imaging Data

A, Sagittal T1 MR imaging. A, Sagittal T1 MR imaging. Multiple bone lesions with T1 hyperintensity involve the cervical and thoracic spine, with a pathologic.

Examples of typical clinical MRI. (A).

Signal intensity is dependent on scaling

A novel method for assessing signal intensity within infrapatellar fat pad on MR images in patients with knee osteoarthritis M. Lu, Z. Chen, W. Han,

Typical MR images of the L2 vertebral body metastasis with pathologic fractures reveal a sharply defined lytic lesion. Typical MR images of the L2 vertebral.

Kirsten Brukamp, MD, Simin Goral, MD, Raymond R. Townsend, MD, Frank E

Coronal (A, B) and sagittal (D) sections of MIP reformations of a MDCTA performed on a 4-row-detector system in a 54-year old woman (patient 10) with an.

Normal MR imaging findings in a 59-year-old man with right SSHL

MR images and plain radiograph of a 73-year-old man who had compression fractures at T12, L1, L3, and L4 vertebral bodies and osteonecrosis at L1 vertebral.

Preoperative T2-weighted magnetic resonance imaging (MRI) (sagittal view) shows disc herniation at the L4-L5 disc level (A) and axial view of MRI shows.

Images reveal arachnoid granulations in a 54-year-old man with headaches who had normal results of an MR imaging study.A, Sagittal reconstruction image.

A, A sagittal fat-saturated T2-weighted image demonstrates increased signal intensity (arrow) in the superior endplate from an acute compression fracture.

Axial T1 fat-suppressed MRI of the lower abdomen obtained after the administration of intravenous gadolinium contrast reveals bright areas of inflammatory.

A–C, Sagittal T1-weighted (A), sagittal T2-weighted (B), and axial T2-weighted (C) MR images of the cervical spine in a patient with severe myelopathy.

A 56-year-old man with fever for 1 week.

Figure 6a. (a-c) Axial T1-weighted GRE MR images (120/4

A 63-year-old man with left L5 radiculopathy on the electromyographic study, who underwent an operation 12 months ago. A 63-year-old man with left L5 radiculopathy.

Sagittal noncontrast T1WI MR imaging of the cervical, thoracic, and upper lumbar spine demonstrates a circumferential high signal intensity (arrows) in.

Images from a 62-year-old male patient presenting with a heterogeneous mass in the superior lobe of the right lung. a) Fusion of axial fat-saturated T1-weighted.

Sagittal MR images of patient 8 showing thoracolumbar EDC 1 day post-LP. Sagittal MR images of patient 8 showing thoracolumbar EDC 1 day post-LP. A, Noncontrast.

Fourth ventricular CSF pulsation artifact in four subjects.

Abdominal magnetic resonance imaging of a patient with tuberous sclerosis complex lymphangioleiomyomatosis and multiple small renal angiomyolipomas (arrows)

Cardiac MRI during the acute phase of the illness.

A 90-year-old woman with severe midback pain.

Compressive neuropathy.

MR images in a 69-year-old woman with cervical and thoracic back pain.

Globally increased ASL signal intensity due to artifact.

Normal sciatic nerve. Normal sciatic nerve. A, Coronal T1-weighted spin-echo image (600/10/2) illustrates the normal longitudinal fascicular appearance.

Cerebral magnetic resonance imaging of our patient performed at ∼7

Diffusion weighted magnetic resonance imaging

Presentation transcript:

MRI Artifacts This presentation is available at: Zhuo, J. et al. Radiographics 2006;26: , AAPM/RSNA Physics Tutorial for Residents: MRI Artifacts, Safety and Quality Control

Figure 20. Aliasing artifact caused by phase errors at both sides of the magnet. Image shows a moiré artifact produced by the addition and cancellation of signals. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Figure 19a. Aliasing artifact caused by imaging with too small a field of view. Image shows aliasing artifact. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Figure 19b. Aliasing artifact caused by imaging with too small a field of view. Image obtained with the phase encoding and frequency encoding axes exchanged shows no aliasing. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Figure 7a. Motion-related artifacts. Abdominal image obtained without breath hold shows breathing-related motion artifacts. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Figure 7b. Motion-related artifacts. Abdominal image obtained with breath hold shows a minimal artifact due to respiration and several motion artifacts due to cardiac pulsation. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Figure 11a. Control of flow-related artifacts. (a) Image shows a cardiac pulsation artifact. (b, c) Images obtained with a saturation band superior to the imaging section (b) and with first-order motion compensation (c) show less severe flow-related artifacts. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26: (a)

Figure 11b. Control of flow-related artifacts. (a) Image shows a cardiac pulsation artifact. (b, c) Images obtained with a saturation band superior to the imaging section (b) and with first-order motion compensation (c) show less severe flow-related artifacts. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26: (b)

Figure 11c. Control of flow-related artifacts. (a) Image shows a cardiac pulsation artifact. (b, c) Images obtained with a saturation band superior to the imaging section (b) and with first-order motion compensation (c) show less severe flow-related artifacts. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26: (c)

Figure 13a. Echo-planar images show magnetic susceptibility artifacts. Left-right phase encoding causes severe distortion of the signal (arrows). Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Figure 14. Sagittal MR image shows a magnetic susceptibility artifact that resulted from the presence of metallic dental fillings Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Figure 15a. Chemical shift artifact at echo-planar imaging. Image shows severe chemical shift artifact from insufficient fat suppression. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Copyright ©Radiological Society of North America, 2006 Figure 15b. Chemical shift artifact at echo-planar imaging. Image obtained with fat saturation shows minimization of the chemical shift artifact or off-resonance effect. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26:

Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26: Figure 5a. Spike artifact. Bad data points in k-space (arrow in b) result in band artifacts on the MR image in a. The location of the bad data points, and their distance from the center of k-space, determine the angulation of the bands and the distance between them. The intensity of the spike determines the severity of the artifact.

Figure 5b. Spike artifact. Bad data points in k-space (arrow in b) result in band artifacts on the MR image in a. The location of the bad data points, and their distance from the center of k-space, determine the angulation of the bands and the distance between them. The intensity of the spike determines the severity of the artifact. Copyright ©Radiological Society of North America, 2006 Zhuo, J. et al. Radiographics 2006;26: