Editing Medical ultrasound (section)

==Expansions==
An additional expansion of ultrasound is '''bi-planar ultrasound''', in which the probe has two 2D planes perpendicular to each other, providing more efficient localization and detection.<ref name=reves/> Furthermore, an '''omniplane''' probe can rotate 180° to obtain multiple images.<ref name=reves>Page 161 (part II > Two-dimensional Echocardiography) in: {{cite book |author1=Reves, J. G. |author2=Estafanous, Fawzy G. |author3=Barash, Paul G. |title=Cardiac anesthesia: principles and clinical practice |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year=2001 |isbn=978-0-7817-2195-0 |url=https://books.google.com/books?id=45DKiUj1hLUC}}</ref> In [[3D ultrasound]], many 2D planes are digitally added together to create a 3-dimensional image of the object.

{{anchor|doppler}}

=== Doppler ultrasonography ===
{{Main|Doppler ultrasonography}}
[[File:ColourDopplerA.jpg|thumb|right|Duplex scan of the common carotid artery]]

[[Doppler ultrasonography]] employs the [[Doppler effect]] to assess whether structures (usually blood)<ref name="WearableUSG"/><ref name="L'Investigation vasculaire par ultrasonographie doppler">{{cite book | first= Claude | last= Franceschi | title=L'Investigation vasculaire par ultrasonographie doppler| publisher= Masson|year=1978 |isbn=978-2-225-63679-0}}</ref> are moving towards or away from the probe, and their relative velocity. By calculating the frequency shift of a particular sample volume, flow in an artery or a jet of blood flow over a heart valve, its speed and direction can be determined and visualized, as an example. ''Color Doppler'' is the measurement of velocity by color scale. Color Doppler images are generally combined with gray scale ([[#Modes|B-mode]]) images to display ''duplex ultrasonography'' images.<ref>{{cite journal |last1=Saxena |first1=A |last2=Ng |first2=EYK |last3=Lim |first3=ST |title=Imaging modalities to diagnose carotid artery stenosis: progress and prospect. |journal=BioMedical Engineering OnLine |date=28 May 2019 |volume=18 |issue=1 |pages=66 |doi=10.1186/s12938-019-0685-7 |pmid=31138235|pmc=6537161 |doi-access=free }}</ref> Uses include:
* [[Doppler echocardiography]] is the use of Doppler ultrasonography to examine the [[heart]].<ref>{{cite web|url=https://medlineplus.gov/ency/article/003869.htm|title=Echocardiogram|website=[[MedlinePlus]]|access-date=2017-12-15}}</ref> An echocardiogram can, within certain limits, produce accurate assessment of the direction of [[blood flow]] and the [[velocity]] of blood and cardiac tissue at any arbitrary point using the Doppler effect. Velocity measurements allow assessment of [[cardiac valve]] areas and function, abnormal communications between the left and right side of the heart, leaking of blood through the valves ([[valvular regurgitation]]), and calculation of the [[cardiac output]] and [[E/A ratio]]<ref name="Mohamed">[http://www.bioline.org.br/request?mj04008] Abdul Latif Mohamed, Jun Yong, Jamil Masiyati, Lee Lim, Sze Chec Tee. ''The Prevalence Of Diastolic Dysfunction In Patients With Hypertension Referred For Echocardiographic Assessment of Left Ventricular Function.'' Malaysian Journal of Medical Sciences, Vol. 11, No. 1, January 2004, pp. 66–74</ref> (a measure of [[diastolic dysfunction]]). Contrast-enhanced ultrasound using gas-filled microbubble contrast media can be used to improve velocity or other flow-related measurements of interest.
* [[Transcranial Doppler]] (TCD) and transcranial color Doppler (TCCD), measure the velocity of [[blood flow]] through the [[brain]]'s [[blood vessel]]s through the [[skull|cranium]]. They are useful in the diagnosis of [[emboli]], [[stenosis]], [[vasospasm]] from a subarachnoid [[hemorrhage]] (bleeding from a ruptured [[aneurysm]]), and other problems.
* [[Doppler fetal monitor]]s use the Doppler effect to detect the [[fetal heartbeat]] during [[prenatal care]]. These are hand-held, and some models also display the [[heart rate]] in beats per minute (BPM). Use of this monitor is sometimes known as ''Doppler [[auscultation]]''. The Doppler fetal monitor is commonly referred to simply as a ''Doppler'' or ''fetal Doppler'' and provides information similar to that provided by a [[fetal stethoscope]].

=== Contrast ultrasonography (ultrasound contrast imaging) ===
{{Main|Contrast-enhanced ultrasound}}

A [[contrast media|contrast medium]] for medical ultrasonography is a formulation of encapsulated gaseous microbubbles<ref>{{cite journal |doi=10.1111/j.1540-8175.1999.tb00144.x |title=Characteristics of SonoVue™ |year=1999 |last1=Schneider |first1=Michel |journal=Echocardiography |volume=16 |pages=743–746 |pmid=11175217 |issue=7, Pt 2|s2cid=73314302 }}</ref> to increase [[echogenicity]] of blood, discovered by Dr. Raymond Gramiak in 1968<ref>{{cite journal |doi=10.1097/00004424-196809000-00011 |title=Echocardiography of the Aortic Root |year=1968 |last1=Gramiak |first1=Raymond |last2=Shah |first2=Pravin M. |journal=Investigative Radiology |volume=3 |issue=5 |pages=356–66 |pmid=5688346}}</ref> and named [[contrast-enhanced ultrasound]]. This contrast [[medical imaging]] modality is used throughout the world,<ref>{{cite web|url=http://www.icus-society.org/attachments/article/103/ICUS%20CEUS%20Use%20Around%20the%20World-2.pdf |title=CEUS Around the World – The International Contrast Ultrasound Society (ICUS) |date=October 2013 |access-date=2013-10-27 |url-status=dead |archive-url=https://web.archive.org/web/20131029213232/http://www.icus-society.org/attachments/article/103/ICUS%20CEUS%20Use%20Around%20the%20World-2.pdf |archive-date=October 29, 2013 }}</ref> for [[echocardiography]] in particular in the United States and for ultrasound [[radiology]] in [[Europe]] and [[Asia]].

Microbubbles-based contrast media is administered [[intravenously]] into the patient [[blood stream]] during the ultrasonography examination. Due to their size, the microbubbles remain confined in [[blood vessels]] without extravasating towards the [[interstitial fluid]]. An [[ultrasound]] contrast media is therefore purely intravascular, making it an ideal agent to image [[Biological system|organ]] microvasculature for [[Medical diagnosis|diagnostic]] purposes. A typical clinical use of contrast ultrasonography is detection of a [[hypervascular]] [[Metastasis|metastatic]] tumor, which exhibits a contrast uptake (kinetics of microbubbles concentration in blood circulation) faster than healthy [[Tissue (biology)|biological tissue]] surrounding the [[tumor]].<ref>{{cite journal |doi=10.1016/j.ultrasmedbio.2012.09.002 |title=Guidelines and Good Clinical Practice Recommendations for Contrast Enhanced Ultrasound (CEUS) in the Liver – Update 2012 |year=2013 |last1=Claudon |first1=Michel |last2=Dietrich |first2=Christoph F. |last3=Choi |first3=Byung Ihn |last4=Cosgrove |first4=David O. |last5=Kudo |first5=Masatoshi |last6=Nolsøe |first6=Christian P. |last7=Piscaglia |first7=Fabio |last8=Wilson |first8=Stephanie R. |last9=Barr |first9=Richard G. |last10=Chammas |first10=Maria C. |last11=Chaubal |first11=Nitin G. |last12=Chen |first12=Min-Hua |last13=Clevert |first13=Dirk Andre |last14=Correas |first14=Jean Michel |last15=Ding |first15=Hong |last16=Forsberg |first16=Flemming |last17=Fowlkes |first17=J. Brian |last18=Gibson |first18=Robert N. |last19=Goldberg |first19=Barry B. |last20=Lassau |first20=Nathalie |last21=Leen |first21=Edward L.S. |last22=Mattrey |first22=Robert F. |last23=Moriyasu |first23=Fuminori |last24=Solbiati |first24=Luigi |last25=Weskott |first25=Hans-Peter |last26=Xu |first26=Hui-Xiong |journal=Ultrasound in Medicine & Biology |volume=39 |issue=2 |pages=187–210 |pmid=23137926 |author27=World Federation for Ultrasound in Medicine |author28=European Federation of Societies for Ultrasound|hdl=11585/144895 |s2cid=2224370 }}</ref> Other clinical applications using contrast exist, as in echocardiography to improve delineation of [[left ventricle]] for visualizing contractibility of [[heart]] muscle after a [[myocardial infarction]]. Finally, applications in quantitative perfusion<ref>{{cite journal |doi=10.1055/s-0031-1281676 |title=The EFSUMB Guidelines and Recommendations on the Clinical Practice of Contrast Enhanced Ultrasound (CEUS): Update 2011 on non-hepatic applications |year=2011 |last1=Piscaglia |first1=F. |last2=Nolsøe |first2=C. |last3=Dietrich |first3=C. |last4=Cosgrove |first4=D. |last5=Gilja |first5=O. |last6=Bachmann Nielsen |first6=M. |last7=Albrecht |first7=T. |last8=Barozzi |first8=L. |last9=Bertolotto |first9=M. |last10=Catalano |first10=O. |last11=Claudon |first11=M. |last12=Clevert |first12=D. |last13=Correas |first13=J. |last14=d'Onofrio |first14=M. |last15=Drudi |first15=F. |last16=Eyding |first16=J. |last17=Giovannini |first17=M. |last18=Hocke |first18=M. |last19=Ignee |first19=A. |last20=Jung |first20=E. |last21=Klauser |first21=A. |last22=Lassau |first22=N. |last23=Leen |first23=E. |last24=Mathis |first24=G. |last25=Saftoiu |first25=A. |last26=Seidel |first26=G. |last27=Sidhu |first27=P. |last28=Ter Haar |first28=G. |last29=Timmerman |first29=D. |last30=Weskott |first30=H. |journal=Ultraschall in der Medizin |volume=33 |pages=33–59 |pmid=21874631 |issue=1|doi-access=free }}</ref> (relative measurement of [[blood flow]]<ref>{{cite journal |doi=10.1098/rsfs.2011.0026 |title=Quantitative contrast-enhanced ultrasound imaging: A review of sources of variability |year=2011 |last1=Tang |first1=M.- X. |last2=Mulvana |first2=H. |last3=Gauthier |first3=T. |last4=Lim |first4=A. K. P. |last5=Cosgrove |first5=D. O. |last6=Eckersley |first6=R. J. |last7=Stride |first7=E. |journal=Interface Focus |volume=1 |issue=4 |pages=520–39 |pmid=22866229 |pmc=3262271}}</ref>) have emerged for identifying early patient response to anti-cancerous drug treatment (methodology and clinical study by Dr. Nathalie Lassau in 2011<ref>{{cite journal |doi=10.1148/radiol.10091870 |title=Advanced Hepatocellular Carcinoma: Early Evaluation of Response to Bevacizumab Therapy at Dynamic Contrast-enhanced US with Quantification—Preliminary Results |year=2010 |last1=Lassau |first1=N. |last2=Koscielny |first2=S. |last3=Chami |first3=L. |last4=Chebil |first4=M. |last5=Benatsou |first5=B. |last6=Roche |first6=A. |last7=Ducreux |first7=M. |last8=Malka |first8=D. |last9=Boige |first9=V. |journal=Radiology |volume=258 |pages=291–300 |pmid=20980447 |issue=1  }}</ref>), enabling the best oncological [[Therapeutic ultrasound|therapeutic]] options to be determined.<ref>{{cite journal |doi=10.1111/liv.12098 |title=Hepatocellular carcinoma treated with sorafenib: Early detection of treatment response and major adverse events by contrast-enhanced US |year=2013 |last1=Sugimoto |first1=Katsutoshi |last2=Moriyasu |first2=Fuminori |last3=Saito |first3=Kazuhiro |last4=Rognin |first4=Nicolas |last5=Kamiyama |first5=Naohisa |last6=Furuichi |first6=Yoshihiro |last7=Imai |first7=Yasuharu |journal=Liver International |volume=33 |issue=4 |pages=605–15 |pmid=23305331|s2cid=19338115 }}</ref>

[[File:Parametric Imaging of Vascular Signatures.jpg|thumb|Parametric imaging of vascular signatures (diagram)]]

In [[oncological]] practice of medical contrast ultrasonography, clinicians use 'parametric imaging of vascular signatures'<ref>{{cite journal |doi=10.1109/TUFFC.2010.1716 |title=Parametric imaging for characterizing focal liver lesions in contrast-enhanced ultrasound |year=2010 |last1=Rognin |first1=N G |last2=Arditi |first2=M |last3=Mercier |first3=L |last4=Frinking |first4=P J A |last5=Schneider |first5=M |last6=Perrenoud |first6=G |last7=Anaye |first7=A |last8=Meuwly |first8=J |last9=Tranquart |first9=F |journal=IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control |volume=57 |issue=11 |pages=2503–11 |pmid=21041137  |s2cid=19339331 }}</ref> invented by Dr. Nicolas Rognin in 2010.<ref>{{cite web|title=Parametric images based on dynamic behavior over time|url=http://patentscope.wipo.int/search/en/WO2011026866|website= International Patent|publisher=World Intellectual Property Organization (WIPO) |vauthors=Rognin N, etal |pages=1–44|year=2010}}</ref> This method is conceived as a [[cancer]] aided diagnostic tool, facilitating characterization of a suspicious [[tumor]] ([[Malignant tumor|malignant]] versus [[Benign tumor|benign]]) in an organ. This method is based on medical [[computational science]]<ref>{{cite journal |doi=10.1055/s-0032-1312894 |title=Perfusion Quantification in Contrast-Enhanced Ultrasound (CEUS) – Ready for Research Projects and Routine Clinical Use |year=2012 |last1=Tranquart |first1=F. |last2=Mercier |first2=L. |last3=Frinking |first3=P. |last4=Gaud |first4=E. |last5=Arditi |first5=M. |journal=Ultraschall in der Medizin |volume=33 |pages=S31–8 |pmid=22723027|s2cid=8513304 }}</ref><ref>{{cite journal |doi=10.1016/j.cag.2010.12.005 |title=Interactive visual analysis of contrast-enhanced ultrasound data based on small neighborhood statistics |year=2011 |last1=Angelelli |first1=Paolo |last2=Nylund |first2=Kim |last3=Gilja |first3=Odd Helge |last4=Hauser |first4=Helwig |journal=Computers & Graphics |volume=35 |issue=2 |pages=218–226}}</ref> to analyze a time sequence of ultrasound contrast images, a digital video recorded in real-time during patient examination. Two consecutive [[signal processing]] steps are applied to each [[pixel]] of the tumor:
# calculation of a vascular signature (contrast uptake difference with respect to healthy tissue surrounding the tumor);
# automatic [[Pattern recognition|classification]] of the vascular signature into a unique [[parameter]], the latter coded in one of the four following [[color]]s:
#* [[green]] for continuous hyper-enhancement (contrast uptake higher than healthy tissue one),
#* [[blue]] for continuous hypo-enhancement (contrast uptake lower than healthy tissue one),
#* [[red]] for fast hyper-enhancement (contrast uptake before healthy tissue one) or
#* [[yellow]] for fast hypo-enhancement (contrast uptake after healthy tissue one).

Once [[signal processing]] in each pixel is completed, a color spatial map of the parameter is displayed on a [[computer monitor]], summarizing all [[Blood vessel|vascular]] information of the tumor in a single image called a parametric image (see last figure of press article<ref>Barnes E, [http://www.auntminnie.com/index.aspx?sec=ser&sub=def&pag=dis&ItemID=91487 Contrast US processing tool shows malignant liver lesions], AuntMinnie.com, 2010.</ref> as clinical examples). This parametric image is interpreted by clinicians based on predominant colorization of the tumor: red indicates a suspicion of [[malignancy]] (risk of cancer), green or yellow – a high probability of benignity. In the first case (suspicion of [[malignant tumor]]), the clinician typically prescribes a biopsy to confirm the diagnostic or a [[CT scan]] examination as a second opinion. In the second case (quasi-certain of [[benign tumor]]), only a follow-up is needed with a contrast ultrasonography examination a few months later. The main clinical benefits are to avoid a systemic biopsy (with inherent risks of invasive procedures) of benign tumors or a CT scan examination exposing the patient to [[X-ray]] radiation. The parametric imaging of vascular signatures method proved to be effective in humans for characterization of tumors in the liver.<ref>{{cite journal |doi=10.1148/radiol.11101866 |title=Differentiation of Focal Liver Lesions: Usefulness of Parametric Imaging with Contrast-enhanced US |year=2011 |last1=Anaye |first1=A. |last2=Perrenoud |first2=G. |last3=Rognin |first3=N. |last4=Arditi |first4=M. |last5=Mercier |first5=L. |last6=Frinking |first6=P. |last7=Ruffieux |first7=C. |last8=Peetrons |first8=P. |last9=Meuli |first9=R. |last10=Meuwly |first10=J.-Y. |journal=Radiology |volume=261 |pages=300–10 |pmid=21746815 |issue=1|doi-access=free }}</ref> In a [[cancer screening]] context, this method might be potentially applicable to other organs such as [[Breast cancer|breast]]<ref>{{cite journal |doi=10.4048/jbc.2013.16.2.208 |title=Diagnostic Value of Contrast-Enhanced Ultrasound Parametric Imaging in Breast Tumors |year=2013 |last1=Yuan |first1=Zhang |last2=Quan |first2=Jiang |last3=Yunxiao |first3=Zhang |last4=Jian |first4=Chen |last5=Zhu |first5=He |last6=Liping |first6=Gong |journal=Journal of Breast Cancer |volume=16 |issue=2 |pages=208–13 |pmid=23843855 |pmc=3706868}}</ref> or [[Prostate cancer|prostate]].

=== Molecular ultrasonography (ultrasound molecular imaging) ===
The current future of contrast ultrasonography is in [[molecular imaging]] with potential clinical applications expected in [[cancer screening]] to detect [[malignant tumor]]s at their earliest stage of appearance. Molecular ultrasonography (or ultrasound molecular imaging) uses targeted microbubbles originally designed by Dr [[Alexander Klibanov (biologist)|Alexander Klibanov]] in 1997;<ref>{{cite journal |pmid=9240089 |year=1997|last1=Klibanov|first1=A. L. |last2=Hughes |first2=M. S. |last3=Marsh |first3=J. N. |last4=Hall |first4=C. S. |last5=Miller |first5=J. G. |last6=Wilble |first6=J. H. |last7=Brandenburger |first7=G. H. |title=Targeting of ultrasound contrast material. An in vitro feasibility study |volume=412 |pages=113–120 |journal=Acta Radiologica Supplementum}}</ref><ref>{{cite journal |doi=10.1016/S0169-409X(98)00104-5 |title=Targeted delivery of gas-filled microspheres, contrast agents for ultrasound imaging |year=1999 |last1=Klibanov |first1=A |journal=Advanced Drug Delivery Reviews |volume=37 |pages=139–157 |pmid=10837732 |issue=1–3}}</ref> such targeted microbubbles specifically bind or adhere to tumoral microvessels by targeting [[biomolecular]] cancer expression (overexpression of certain biomolecules that occurs during [[Angiogenesis|neo-angiogenesis]]<ref>{{cite journal |pmid=20027118 |year=2010 |last1=Pochon |first1=S |last2=Tardy |first2=I |last3=Bussat |first3=P |last4=Bettinger |first4=T |last5=Brochot |first5=J |last6=Von Wronski |first6=M |last7=Passantino |first7=L |last8=Schneider |first8=M |title=BR55: A lipopeptide-based VEGFR2-targeted ultrasound contrast agent for molecular imaging of angiogenesis |volume=45 |issue=2 |pages=89–95 |doi=10.1097/RLI.0b013e3181c5927c |journal=Investigative Radiology|s2cid=24089981 }}</ref><ref>{{cite journal |doi=10.2967/jnumed.109.068007 |title=Targeted Contrast-Enhanced Ultrasound Imaging of Tumor Angiogenesis with Contrast Microbubbles Conjugated to Integrin-Binding Knottin Peptides |year=2010 |last1=Willmann |first1=J. K. |last2=Kimura |first2=R. H. |last3=Deshpande |first3=N. |last4=Lutz |first4=A. M. |last5=Cochran |first5=J. R. |last6=Gambhir |first6=S. S. |journal=Journal of Nuclear Medicine |volume=51 |issue=3 |pages=433–40 |pmid=20150258 |pmc=4111897}}</ref> or [[inflammation]]<ref>{{cite journal |pmid=15052252 |year=2004 |last1=Lindner |first1=JR |title=Molecular imaging with contrast ultrasound and targeted microbubbles |volume=11 |issue=2 |pages=215–21 |doi=10.1016/j.nuclcard.2004.01.003 |journal=Journal of Nuclear Cardiology|s2cid=36487102 }}</ref> in malignant tumors). As a result, a few minutes after their injection in blood circulation, the targeted microbubbles accumulate in the malignant tumor; facilitating its localization in a unique ultrasound contrast image. In 2013, the very first exploratory [[clinical trial]] in humans for [[prostate cancer]] was completed at [[Amsterdam]] in the [[Netherlands]] by Dr. Hessel Wijkstra.<ref>{{ClinicalTrialsGov|NCT01253213|BR55 in Prostate Cancer: an Exploratory Clinical Trial}}</ref>

In molecular ultrasonography, the technique of [[acoustic radiation force]] (also used for shear wave [[elastography]]) is applied in order to literally push the targeted microbubbles towards microvessels wall; first demonstrated by Dr. Paul Dayton in 1999.<ref>{{cite journal |doi=10.1016/S0301-5629(99)00062-9 |title=Acoustic radiation force in vivo: A mechanism to assist targeting of microbubbles |year=1999 |last1=Dayton |first1=Paul |last2=Klibanov |first2=Alexander |last3=Brandenburger |first3=Gary |author4-link=Ferrara, Kathy |last4=Ferrara, Kathy |journal=Ultrasound in Medicine & Biology |volume=25 |issue=8 |pages=1195–1201 |pmid=10576262}}</ref> This allows maximization of binding to the malignant tumor; the targeted microbubbles being in more direct contact with cancerous biomolecules expressed at the inner surface of tumoral microvessels. At the stage of scientific [[preclinical]] research, the technique of acoustic radiation force was implemented as a prototype in clinical ultrasound systems and validated ''[[in vivo]]'' in 2D<ref>{{cite journal |doi=10.1016/j.ultrasmedbio.2012.03.018 |title=Effects of Acoustic Radiation Force on the Binding Efficiency of BR55, a VEGFR2-Specific Ultrasound Contrast Agent |year=2012 |last1=Frinking |first1=Peter J.A. |last2=Tardy |first2=Isabelle |last3=Théraulaz |first3=Martine |last4=Arditi |first4=Marcel |last5=Powers |first5=Jeffry |last6=Pochon |first6=Sibylle |last7=Tranquart |first7=François |journal=Ultrasound in Medicine & Biology |volume=38 |issue=8 |pages=1460–9 |pmid=22579540}}</ref> and 3D<ref>{{cite journal |doi=10.1016/j.ultrasmedbio.2011.12.005 |title=An In Vivo Validation of the Application of Acoustic Radiation Force to Enhance the Diagnostic Utility of Molecular Imaging Using 3-D Ultrasound |year=2012 |last1=Gessner |first1=Ryan C. |last2=Streeter |first2=Jason E. |last3=Kothadia |first3=Roshni |last4=Feingold |first4=Steven |last5=Dayton |first5=Paul A. |journal=Ultrasound in Medicine & Biology |volume=38 |issue=4 |pages=651–60 |pmid=22341052|pmc=3355521 }}</ref><ref>{{cite journal|last=Rognin N |title=Molecular Ultrasound Imaging Enhancement by Volumic Acoustic Radiation Force (VARF): Pre-clinical in vivo Validation in a Murine Tumor Model |journal=World Molecular Imaging Congress, Savannah, GA, USA |year=2013 |url=http://wmis2013.omnibooksonline.com/data/papers/P380.htm |display-authors=etal |url-status=dead |archive-url=https://web.archive.org/web/20131011213605/http://wmis2013.omnibooksonline.com/data/papers/P380.htm |archive-date=October 11, 2013 }}</ref> imaging modes.

=== Elastography (ultrasound elasticity imaging) ===
{{Main|Elastography}}
Ultrasound is also used for elastography, which is a relatively new imaging modality that maps the elastic properties of soft tissue.<ref name=Wells>{{cite journal | author = Wells P. N. T. | year = 2011 | title = Medical ultrasound: imaging of soft tissue strain and elasticity | journal = Journal of the Royal Society, Interface | volume = 8 | issue = 64| pages = 1521–1549 | doi = 10.1098/rsif.2011.0054 | pmid = 21680780 | pmc = 3177611 }}</ref><ref name=Sarv>{{cite journal|vauthors=Sarvazyan A, Hall TJ, Urban MW, Fatemi M, Aglyamov SR, Garra BS |pmc=3269947 |title=Overview of elastography–an emerging branch of medical imaging|journal=Current Medical Imaging Reviews |volume=7 |issue=4 |pages=255–282 |year=2011 |pmid=22308105 |doi=10.2174/157340511798038684}}</ref> This modality emerged in the last two decades. Elastography is useful in medical diagnoses as it can discern healthy from unhealthy tissue for specific organs/growths. For example, cancerous tumors will often be harder than the surrounding tissue, and diseased livers are stiffer than healthy ones.<ref name=Wells/><ref name=Sarv/><ref>{{cite journal|author1=Ophir, J. |author2=Céspides, I. |author3=Ponnekanti, H. |author4=Li, X. |title=Elastography: A quantitative method for imaging the elasticity of biological tissues|journal=Ultrasonic Imaging|volume=13|issue=2|pages=111–34|doi=10.1016/0161-7346(91)90079-W|pmid=1858217|year=1991}}</ref><ref>{{cite journal|author1=Parker, K J |author2=Doyley, M M |author3=Rubens, D J |title=Corrigendum: Imaging the elastic properties of tissue: The 20 year perspective|journal=Physics in Medicine and Biology|volume=57|issue=16|pages=5359–5360|doi=10.1088/0031-9155/57/16/5359|year=2012|bibcode=2012PMB....57.5359P|doi-access=free}}</ref>

There are many ultrasound elastography techniques.<ref name=Sarv/>

===Interventional ultrasonography===
Interventional ultrasonography involves [[biopsy]], emptying fluids, intrauterine [[Blood transfusion]] ([[Hemolytic disease of the newborn]]).
* [[Thyroid cyst]]s: High frequency thyroid [[ultrasound]] (HFUS) can be used to treat several gland conditions. The recurrent thyroid cyst that was usually treated in the past with surgery, can be treated effectively by a new procedure called percutaneous ethanol injection, or PEI.<ref>{{cite journal |last1=Halenka |first1=Milan |last2=Karasek |first2=David |last3=Schovanek |first3=Jan |last4=Frysak |first4=Zdenek |title=Safe and effective percutaneous ethanol injection therapy of 200 thyroid cysts |journal=Biomedical Papers |date=18 June 2020 |volume=164 |issue=2 |pages=161–167 |doi=10.5507/bp.2019.007|pmid=30945701 |s2cid=92999405 |doi-access=free }}</ref><ref>{{cite journal |last1=Ozderya |first1=Aysenur |last2=Aydin |first2=Kadriye |last3=Gokkaya |first3=Naile |last4=Temizkan |first4=Sule |title=Percutaneous Ethanol Injection for Benign Cystic and Mixed Thyroid Nodules |journal=Endocrine Practice |date=June 2018 |volume=24 |issue=6 |pages=548–555 |doi=10.4158/EP-2018-0013|pmid=29624094 |s2cid=4665114 }}</ref> With ultrasound guided placement of a 25 gauge needle within the cyst, and after evacuation of the cyst fluid, about 50% of the cyst volume is injected back into the cavity, under strict operator visualization of the needle tip. The procedure is 80% successful in reducing the cyst to minute size.
* Metastatic thyroid cancer neck lymph nodes: HFUS may also be used to treat metastatic thyroid cancer neck lymph nodes that occur in patients who either refuse, or are no longer candidates, for surgery. Small amounts of ethanol are injected under ultrasound guided needle placement. A power doppler blood flow study is done prior to injection. The blood flow can be destroyed and the node rendered inactive. Power doppler visualized blood flow can be eradicated, and there may be a drop in the cancer blood marker test, [[thyroglobulin]], TG, as the node become non-functional. Another interventional use for HFUS is to mark a cancer node prior to surgery to help locate the node cluster at the surgery. A minute amount of methylene dye is injected, under careful ultrasound guided placement of the needle on the anterior surface, but not in the node. The dye will be evident to the thyroid surgeon when opening the neck. A similar localization procedure with methylene blue, can be done to locate parathyroid adenomas.<ref name="YeapRobinson2017">{{cite journal |last1=Yeap |first1=Phey Ming |last2=Robinson |first2=Philip |title=Ultrasound Diagnostic and Therapeutic Injections of the Hip and Groin |journal=Journal of the Belgian Society of Radiology |date=16 December 2017 |volume=101 |issue=Suppl 2 |pages=6 |doi=10.5334/jbr-btr.1371 |pmid=30498802 |pmc=6251072 |doi-access=free }}</ref>
* [[Joint injection]]s can be guided by medical ultrasound, such as in [[ultrasound-guided hip joint injection]]s.

=== Compression ultrasonography ===
Compression ultrasonography is when the probe is pressed against the skin. This can bring the target structure closer to the probe, increasing spatial resolution of it. Comparison of the shape of the target structure before and after compression can aid in diagnosis.

It is used in [[ultrasonography of deep venous thrombosis]], wherein absence of vein compressibility is a strong indicator of thrombosis.<ref name="JAMA">{{cite journal |doi=10.1136/bmj.316.7124.17 |title=Compression ultrasonography for diagnostic management of patients with clinically suspected deep vein thrombosis: Prospective cohort study |year=1998 |last1=Cogo |first1=A. |last2=Lensing |first2=A. W A |last3=Koopman |first3=M. M W |last4=Piovella |first4=F. |last5=Siragusa |first5=S. |last6=Wells |first6=P. S |last7=Villalta |first7=S. |last8=Büller |first8=H. R |last9=Turpie |first9=A. G G |last10=Prandoni |first10=P. |journal=BMJ |volume=316 |issue=7124 |pages=17–20 |pmid=9451260 |pmc=2665362}}</ref> Compression ultrasonography has both high [[sensitivity and specificity]] for detecting proximal deep vein thrombosis in symptomatic patients. Results are not reliable when the patient is asymptomatic, for example in high risk postoperative orthopedic patients.<ref name=medscape>{{cite journal |doi=10.7326/0003-4819-128-8-199804150-00011 |title=Noninvasive Diagnosis of Deep Venous Thrombosis |year=1998 |last1=Kearon |first1=Clive |journal=Annals of Internal Medicine |volume=128 |issue=8 |pages=663–77 |pmid=9537941 |last2=Julian |first2=JA |last3=Newman |first3=TE |last4=Ginsberg |first4=JS|s2cid=13467218 }}</ref><ref>{{cite journal |doi=10.1016/S0140-6736(94)90240-2 |title=Limitations of compression ultrasound for the detection of symptomless postoperative deep vein thrombosis |year=1994 |last1=Jongbloets |first1=L.M.M. |last2=Koopman |first2=M.M.W. |last3=Büller |first3=H.R. |last4=Ten Cate |first4=J.W. |last5=Lensing |first5=A.W.A. |journal=The Lancet |volume=343 |issue=8906 |pages=1142–4 |pmid=7910237|s2cid=23576444 }}</ref>

<gallery heights="180" widths="230">
File:Ultrasonography of a normal appendix without and with compression.jpg|A normal [[appendix (anatomy)|appendix]] without and with compression. Absence of compressibility indicates [[appendicitis]].<ref>{{cite journal|last1=Reddan|first1=Tristan|last2=Corness|first2=Jonathan|last3=Mengersen|first3=Kerrie|author3-link= Kerrie Mengersen |last4=Harden|first4=Fiona|title=Ultrasound of paediatric appendicitis and its secondary sonographic signs: providing a more meaningful finding|journal=Journal of Medical Radiation Sciences|date=March 2016|volume=63|issue=1|pages=59–66|doi=10.1002/jmrs.154|pmid=27087976|pmc=4775827}}</ref>
File:Ultrasonographic measurement of aortic diameter at the navel.svg|Compression is used in this ultrasonograph to get closer to the [[abdominal aorta]], making the [[superior mesenteric vein]] and the [[inferior vena cava]] look rather flat.
</gallery>
{{Anchor|Panoramic}}

===Panoramic ultrasonography===
[[File:Panoramic ultrasonography of biceps tendon rupture - Annotated.jpg|thumb|Panoramic ultrasonography of a proximal [[biceps tendon rupture]]. Top image shows the contralateral normal side, and lower image shows a retracted muscle, with a [[hematoma]] filling out the proximal space.]]
Panoramic ultrasonography is the digital [[image stitching|stitching]] of multiple ultrasound images into a broader one.<ref name=Kumar2010>{{cite journal|title=Panoramic Ultrasound|journal=Conference: Proceedings of the Second National Conference on Signal & Image Processing, at S.M.K. Fomra Institute of Technology Chennai, India|first=Suresh|last=Kumar|url=https://www.researchgate.net/publication/282816212}} April 2010</ref> It can display an entire abnormality and show its relationship to nearby structures on a single image.<ref name=Kumar2010/>

=== Multiparametric ultrasonography ===
Multiparametric ultrasonography (mpUSS) combines multiple ultrasound techniques to produce a composite result. For example, one study combined B-mode, colour Doppler, real-time elastography, and contrast-enhanced ultrasound, achieving an accuracy similar to that of [[MRI sequence|multiparametric MRI]].<ref>{{cite journal |last1=Grey |first1=Alistair D R |last2=Scott |first2=Rebecca |last3=Shah |first3=Bina |last4=Acher |first4=Peter |last5=Liyanage |first5=Sidath |last6=Pavlou |first6=Menelaos |last7=Omar |first7=Rumana |last8=Chinegwundoh |first8=Frank |last9=Patki |first9=Prasad |last10=Shah |first10=Taimur T |last11=Hamid |first11=Sami |last12=Ghei |first12=Maneesh |last13=Gilbert |first13=Kayleigh |last14=Campbell |first14=Diane |last15=Brew-Graves |first15=Chris |last16=Arumainayagam |first16=Nimalan |last17=Chapman |first17=Alex |last18=McLeavy |first18=Laura |last19=Karatziou |first19=Angeliki |last20=Alsaadi |first20=Zayneb |last21=Collins |first21=Tom |last22=Freeman |first22=Alex |last23=Eldred-Evans |first23=David |last24=Bertoncelli-Tanaka |first24=Mariana |last25=Tam |first25=Henry |last26=Ramachandran |first26=Navin |last27=Madaan |first27=Sanjeev |last28=Winkler |first28=Mathias |last29=Arya |first29=Manit |last30=Emberton |first30=Mark |last31=Ahmed |first31=Hashim U |title=Multiparametric ultrasound versus multiparametric MRI to diagnose prostate cancer (CADMUS): a prospective, multicentre, paired-cohort, confirmatory study |journal=The Lancet Oncology |date=March 2022 |volume=23 |issue=3 |pages=428–438 |doi=10.1016/S1470-2045(22)00016-X |pmid=35240084 |s2cid=247178444 |hdl=10044/1/94492 |url=https://discovery.ucl.ac.uk/id/eprint/10145157/ |hdl-access=free }}</ref>

=== Speed-of-Sound Imaging ===
Speed-of-sound (SoS) imaging aims to find the spatial distribution of the SoS within the tissue. The idea is to find relative delay measurements for different transmission events and solve the limited-angle tomographic reconstruction problem using delay measurements and transmission geometry. Compared to shear-wave elastography, SoS imaging has better ex-vivo tissue differentiation<ref>{{cite journal |last1=Glozman |first1=Tanya |last2=Azhari |first2=Haim |title=A Method for Characterization of Tissue Elastic Properties Combining Ultrasonic Computed Tomography With Elastography |journal=Journal of Ultrasound in Medicine |date=March 2010 |volume=29 |issue=3 |pages=387–398 |doi=10.7863/jum.2010.29.3.387 |pmid=20194935 |s2cid=14869006 }}</ref> for benign and malignant tumors.<ref>{{cite journal |last1=Li |first1=Cuiping |last2=Duric |first2=Nebojsa |last3=Littrup |first3=Peter |last4=Huang |first4=Lianjie |title=In vivo Breast Sound-Speed Imaging with Ultrasound Tomography |journal=Ultrasound in Medicine & Biology |date=October 2009 |volume=35 |issue=10 |pages=1615–1628 |doi=10.1016/j.ultrasmedbio.2009.05.011 |pmid=19647920 |pmc=3915527 }}</ref><ref>{{cite journal |last1=Goss |first1=S. A. |last2=Johnston |first2=R. L. |last3=Dunn |first3=F. |title=Compilation of empirical ultrasonic properties of mammalian tissues. II |journal=The Journal of the Acoustical Society of America |date=July 1980 |volume=68 |issue=1 |pages=93–108 |doi=10.1121/1.384509 |pmid=11683186 |bibcode=1980ASAJ...68R..93G }}</ref><ref>{{cite journal |last1=Goss |first1=S. A. |last2=Johnston |first2=R. L. |last3=Dunn |first3=F. |title=Comprehensive compilation of empirical ultrasonic properties of mammalian tissues |journal=The Journal of the Acoustical Society of America |date=August 1978 |volume=64 |issue=2 |pages=423–457 |doi=10.1121/1.382016 |pmid=361793 |bibcode=1978ASAJ...64..423G }}</ref>