Objectives of the Presentation To educate on the identification and causes of various ultrasound artifacts. To provide practical remedies and techniques for minimizing or eliminating these artifacts. To enhance the overall quality and reliability of ultrasound imaging in clinical practice.

1. Ultrasound Image Artifacts And
Their Specific Remedies
Presenter: Dr. Dheeraj Kumar
MRIT, Ph.D. (Radiology and Imaging)
Assistant Professor
Medical Radiology and Imaging Technology
School of Health Sciences, CSJM University, Kanpur

2. Definition of Ultrasound Artifacts
• Artifacts in ultrasound are
errors or distortions in the
image that do not correspond
to actual anatomical structures.
• These artifacts can obscure
important details or create
false representations of tissues
or organs.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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3. Objectives of the Presentation
• To educate on the identification
and causes of various ultrasound
artifacts.
• To provide practical remedies and
techniques for minimizing or
eliminating these artifacts.
• To enhance the overall quality
and reliability of ultrasound
imaging in clinical practice.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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4. Importance of Identifying and
Correcting Artifacts
• Accurate diagnosis: Artifacts can lead to
misdiagnosis or missed pathology if not properly
identified and corrected.
• Image quality: Enhancing image clarity and
accuracy is essential for reliable interpretation.
• Patient care: Correcting artifacts ensures better
patient outcomes by providing accurate
information for treatment planning.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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5. Common Ultrasound Artifacts
A brief list of the most common artifacts that will be covered in the presentation:
• Acoustic Shadowing
• Acoustic Enhancement
• Reverberation
• Mirror Image
• Refraction
• Side Lobes/Grating Lobes
• Speed Error
• Range Ambiguity
• Aliasing Artifact
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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6. Acoustic Shadowing
Dark shadow behind structures that
strongly attenuate the sound beam (e.g.,
bones, stones).
• Causes: High impedance difference
between tissues.
• Remedies:
• Adjust the angle of the ultrasound probe to
avoid strong reflectors.
• Use alternative imaging windows.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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7. Acoustic Enhancement
Increased brightness behind a structure that is
less attenuating (e.g., fluid-filled cysts).
• Causes: Low impedance of fluid-filled
structures.
• Remedies:
• Recognize it as a useful artifact for identifying
cystic structures.
• Adjust gain settings to reduce over-enhancement.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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8. Reverberation Artifacts
Multiple, equally spaced echoes caused
by the sound bouncing between two
strong reflectors.
• Causes: Sound waves repeatedly
reflecting between two surfaces.
• Remedies:
• Change the probe position or angle.
• Use harmonic imaging to reduce
reverberations.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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9. Mirror Image Artifacts
Duplication of structures on the
opposite side of a strong reflector.
• Causes: Reflection from a large,
smooth surface (e.g., diaphragm).
• Remedies:
• Alter the scanning angle to eliminate the
false image.
• Recognize common mirror artifact
patterns.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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10. Refraction Artifacts
Displacement of structures from their
true location due to bending of the
sound beam.
• Causes: Difference in propagation
speeds in adjacent tissues.
• Remedies:
• Adjust scanning angle to minimize beam
refraction.
• Use compound imaging to reduce
refraction artifacts.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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11. Side Lobes/Grating Lobes
False echoes caused by off-axis sound
beams.
• Causes: Ultrasound beam side lobes or
grating lobes.
• Remedies:
• Use of higher frequency probes.
• Apply apodization to reduce side lobes.
• Use subdicing techniques in transducer
design.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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12. Speed Error Artifacts
Displacement of structures in the
image due to incorrect assumptions
about the speed of sound in tissue.
• Causes: Variation in tissue
composition affecting sound speed.
• Remedies:
• Be aware of the artifact when scanning
heterogeneous tissues.
• Use corrective software if available.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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13. Range Ambiguity Artifacts
Incorrect placement of echoes in
the image due to pulse repetition
frequency (PRF) settings.
• Causes: High PRF causing
overlapping echoes.
• Remedies:
• Adjust the PRF to match the depth
of the area of interest.
• Use lower PRF for deeper
structures.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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14. Aliasing Artifacts
Aliasing artifacts in ultrasound appear as false representations of motion or structure, often showing
up as duplicated or mispositioned spectral waveforms. This phenomenon occurs when the sampled
signal frequency exceeds the Nyquist limit, causing the signal to be improperly reconstructed.
• Causes:
• Aliasing occurs due to insufficient sampling rates in Doppler ultrasound, particularly when the
velocity of blood flow or tissue movement exceeds the Nyquist limit (half the pulse repetition
frequency, or PRF).
• This results in an incorrect representation of the frequency shift, leading to a wrapping effect in
the Doppler spectrum.
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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15. Remedies:
1.Increase Pulse Repetition Frequency (PRF):
1. Raising the PRF can help to accommodate higher velocities without
surpassing the Nyquist limit, thereby reducing aliasing.
2.Use Lower Frequency Transducers:
1. Lower frequency transducers have a higher Nyquist limit at the
same PRF, which helps in reducing the occurrence of aliasing.
3.Adjust the Doppler Angle:
1. Changing the angle of insonation to be closer to 0 degrees (parallel
to the flow) can reduce the Doppler shift frequency, minimizing
aliasing.
4.Shift Baseline:
1. Adjusting the baseline of the Doppler spectrum can help to display
higher velocities on the same scale without wrapping around.
5.Utilize Continuous Wave Doppler:
1. Continuous Wave (CW) Doppler does not have a Nyquist limit,
thus eliminating aliasing, though it sacrifices precise depth
information.
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16. References
• Bushberg, J. T., Seibert, J. A., Leidholdt, E. M., & Boone, J. M. (2011). The Essential Physics of
Medical Imaging (3rd ed.). Lippincott Williams & Wilkins.
• Kremkau, F. W. (2015). Diagnostic Ultrasound: Principles and Instruments (9th ed.). Elsevier.
• Hedrick, W. R., Hykes, D. L., & Starchman, D. E. (2005). Ultrasound Physics and Instrumentation
(4th ed.). Elsevier.
• Hoskins, P. R., Martin, K., Thrush, A., & Whittingham, T. A. (2010). Diagnostic Ultrasound:
Physics and Equipment (2nd ed.). Cambridge University Press.
• Szabo, T. L. (2004). Diagnostic Ultrasound Imaging: Inside Out. Elsevier Academic Press.
•
Ultrasound Image Artifacts And Their Specific Remedies By-Dr.
Dheeraj Kumar
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17. Thank You
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Dheeraj Kumar
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