Talk:Ultrasound

message: dubious – discuss
To quote;
"Because of their high amplitude to wavelength ratio, ultrasonic waves commonly display nonlinear propagation."
This is simply not right. You can't have a ratio between different parameters. You can compare an amplitude with another amplitude, or a wavelength with another wavelength, but not with each other.
Nonlinear propagation of sound can occur at any frequency and is caused by high ratios of instantaneous air pressure as they approach a vacuum at a minimum point as you can never have a negative absolute air pressure as that would be beyond a perfect vacuum. Also, at all frequencies, there can be nonlinearity caused by isothermal compression and expansion, but these relate to sound propagation in proximity to a solid or liquid object. 
keoka 01:16, 29 May 2015 (UTC)
replies: text: You're right: uncited nonsense; removed.—Aquegg (talk) 04:59, 29 May 2015 (UTC)
thread_title: Nonlinear propagation effects

message: This articles needs one or more sources, added tag.--FloNight 23:38, 26 November 2005 (UTC)
thread_title: Comment 1

message: Why can not human being hear sounds more than 20 kilohertz??
:Because above 20,000 Hertz (vibrations per second) the waves are too small and fast for the inner ear to transmit the vibrations.  20,000 Hertz is the typical upper limit of hearing, there may be individuals who can detect some frequencies slightly above this range, but not much higher. DuBose 14:06, 11 November 2005 (UTC)
replies: text: It should perhaps also be noted that this limit is lower for many persons - it decreases with age, and it is also decreased by repeated exposure to high-intensity sounds of lower frequencies (loud music being a common example). Osquar F 12:33, 5 December 2006 (UTC)
thread_title: Why can't humans hear ultrasound?

message: More loose descriptions. Waves aren't "big" or "small" or "slow" or "fast" - their properties are amplitude and frequency. Comparative descriptions need a reference to what is not "big", "small", "slow", or "fast". An ant, for instance, is smaller than a person but is larger than a microbe.
A scientific term has to be used in a scientific context. The real reason for a reduced high frequency response at high frequencies is a decrease in sound transmission through various tissues and the organ of Corti in the inner ear which is less responsive to higher frequencies.
keoka 01:16, 29 May 2015 (UTC)
replies: text: It should perhaps also be noted that this limit is lower for many persons - it decreases with age, and it is also decreased by repeated exposure to high-intensity sounds of lower frequencies (loud music being a common example). Osquar F 12:33, 5 December 2006 (UTC)
thread_title: comment

message: Does anyone know why medical sonography uses a typical frequency of 1 to 10 MHz. Why not higher? Are there any constraints on this?
-- I believe this is due to regulations on transmitted power - higher the frequency, the higher the energy in the transmission.  To prevent localized heating, the transmitted energy (and thus the frequency) are limited.  Also, the upper limit is more like 15MHz, IIRC, although that's flexible depending on the specific application.
-- In addition, attenuation of an ultrasound beam is proportional to its frequency, which means that a 10MHz medical imaging beam can only penetrate around 3cm at "safe" power levels.  Only very superficial structures can be scanned in this way.  Higher frequencies can be used in small children where the size and relative depths of structures of interest are smaller, and can also be used in adults in situations where a modified probe can be put inside the body.  Examples of this are trans-esophageal echocardiography, transvaginal sonography and intravascular ultrasound imaging. 
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-- There are actually applications for ultrasound at higher frequency. A new field appeared about 10 years ago, which focuses on small animal imaging, in particular mouse and rat imaging. It is often referred to as ultrasound bio-microscopy (UBM). The frequency for UBM typically ranges from 20 MHz to 60 MHz, which translates to a resolution of 25 to 75 µm axially and about 50 to 150 µm laterally (depending on the geometry of the tranducer). Biology labs and pharmaceutical companies are the principal users of this technology, because it allows them to visualize the progression of model of diseases (for example cancer model) developed in small animals without having to sacrifice these animals at regular time interval (like it used to be done when histology only could provide information about diseased tissues). The efficiency of particular disease treatments can also benefit from this technology.
Also, ultrasound scanners are also on the market for specific human applications. Intra vascular ultrasound is one of them (30-40 MHz, typically). Opthalmology is also an application for which high frequency ultrasound scanners are commercialized (20 MHz for imaging of the retina, 40-50 MHz for imaging of the cornea). Dermatology could also benefit from UBM technology.
The increase of the attenuation as a function of frequency is for sure an issue when dealing with high frequency ultrasound, especially because it limits the depth of penetration (UBM scanner can image at a maximum depth of around 10 to 20 mm, depending on the frequency used). However, another type of limitations has prevented for a long time higher frequency to be used for imaging. And it has to do with the capability (or motivation, the market was maybe not there yet) of manufacturers to develop transducers operating in the high frequency range. To date, commercially available UBM scanners are still using a single element transducer collecting data from one particular location, and mechanically scanned across the sample to produce images. This mechanical scan limits drastically the imaging frame rate (60 fps, typically). Furthermore, the use of single element transducers limit the number of focal zones to a single one. Whereas in the clinical frequency range, single element transducers have been replaced a long time ago by transducers array, which in combination with beamforming techniques, can generate multiple foci, can steer the beam, and can scan across the sample without being actually physically moved spatially, allowing for frame rate well above 100 frames per second. Some research labs around the world are however working on the development of transducers array for UBM, but it is a very challenging task, because structures in these arrays that are 100's microns in size, would have to be let say 10 times smaller for high frequency arrays. 
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You seem to be changing every use of "ultrasonography" with "sonography". I wish you'd discussed this on the relevant talk pages first. I think the correct term is "ultrasonography" if the test is called "an ultrasound". I've changed it back for now. Please provide some support for your changes. JFW | T@lk 14:32, 11 November 2005 (UTC)
replies: text: This discussion should be conducted on talk:medical ultrasonography and not here. JFW | T@lk 01:50, 13 November 2005 (UTC)
thread_title: Sonography

message: Does anyone know anything about the communication devices used by divers?--Gbleem 01:28, 22 November 2005 (UTC)
thread_title:  ultrasound communication for underwater 

message: The principles of ultrasound are the same irrespective of the application.  Several contributors have defined ultrasound in terms of its use in medicine, with little more than a cursory nod toward it's use in industry.  Although in modern times the use of ultrasound is much more widespread in medicine and thus more familiar to the public at large, it is in a comparitively narrow field and uses a small range of frequencies, in the MHz range, which are suited to human tissue and bone.  In industrial nondestructive testing (NDT) the uses are far more varied and the range of frequencies varies from 100's of Khz up to many Ghz.  Such applications include, crack detection and sizing, bond testing, material evaluation and ultrasonic microscopy.  Hardware ranges from single probe in pulse-echo mode - ie sending and receiving its own pulse, thru inspection systems used in the oil and gas industry containing many probes up to multi-element arrays capable of producing a real-time image of the object under test (herein lies the parallel with medical imaging).  Lionel Dunlop (talk) 22:25, 23 February 2009 (UTC)
thread_title:  Principles 

message: Quite correctly, ultrasound is defined as "above the frequency at which the average human can hear", i.e. approximately 16khz but then the rather bold statement is made that because Bats and certain other animals' threshold is higher, "they can hear Ultrasound".  This is very misleading. Admittedly, certain species of bat can hear up to 160 khz but this is a minute proportion of the full spectrum of Ultrasound, which as I have already said is well into the Ghz range.   Lionel Dunlop (talk) 22:24, 23 February 2009 (UTC)
thread_title:  Definition 

message: Extracorporeal shock wave lithotripsy is not an ultrasound application. Seejyb 23:54, 14 November 2006 (UTC)
thread_title:  ESWL is not Ultrasound 

message: Currently, all of the images are of fetuses. These are definitely valuable pictures for this article, as that's a common and well-known use of ultrasounds. I think it would also be beneficial, however, to have an image or two of other medical ultrasounds to further illustrate (no pun intended) that they have other medical uses as well. I don't have any, unfortunately, but it would be a nice addition if someone does. Maybe the CDC website or another US Government health-related department would? Just throwing that out there, as images by the US Government don't have the same copyright issues. --Icarus (Hi!) 18:47, 31 December 2006 (UTC)
thread_title:  Additional images? 

message: I really like this paragraph, but it just doesn't fit in this article at the moment. LightYear 01:18, 11 January 2007 (UTC)
replies: text: I really like it too, but I agree that it should go somewhere else.   Right now I'm thinking of moving it to the "wave" article, although that's not exactly right either.  Ideally there should be an article on non-linear wave propigation for this information, but it would need more mathematical models and some sources.Dudecon 19:06, 12 January 2007 (UTC)

text: okay, I looked around and this kind of non-linear behaviour only occurs in pressure waves.  This is primarily an acoustic effect, so it should go in an acoustic related article.  I've created a stub for Nonlinear Acoustics and coppy-pasted the paragraph there as a seed.  I don't know much about the topic personally, so I tagged it for attention by an expert. —The preceding unsigned comment was added by Dudecon (talk • contribs) 19:37, 12 January 2007 (UTC)
thread_title:  Non-linear propagation 

message: Children can hear it, just as most adults can and the NYT is full of baloney on this point. I'm 40 with a long history of listening to music much louder than I should and I can hear it clearly from a considerable distance, as can my 38 yr old wife, and co-workers ranging in age from 42 to 60. This is just silliness. Additionally, the statement begins, "Some have said that children can hear some high-pitched sounds that older adults cannot hear..." The sole reference does back up the point that there is a bogus ring tone that was alledgedly created (or at least used) because adults supposedly can't hear it, however untrue that reality may be, but there is no reference to back up the assertion that children (as a rule) can hear sounds that adults cannot (as a rule) hear.  Darentig 16:56, 5 April 2007 (UTC)
replies: text: I agree the info on a mobile phone ring tone is trivial at best and nonsense at worst. I propose cleaning this section up by removing the mention of the ring tone, and explicitly stating that the upper limit of hearing is different for different folks, and that in general, this upper limit comes down as age increase. We are all happy to agree on this as fact, are we? LightYear 04:29, 10 April 2007 (UTC)
replies: text: It is definitely true that many adults over the age of around 40 begin to lose some of the very-highest-frequency hearing, and that this loss progresses into old age; I've added a reference about this to the article. The enormous variation in this phenomenon across the population means that, although the ringtone's creation has some basis in fact, it's essentially pointless because a significant proportion of adults will easily hear it. I do not think that the ringtone paragraph should be removed - it helps make the topic interesting to the casual reader. --mcld 20:41, 10 April 2007 (UTC)
replies: text:  Sounds (haha) good. Thanks for the edit. I'm happy with that section now. LightYear 23:24, 10 April 2007 (UTC)
thread_title:  "younger humans": the mosquito ring tone. 

message: None of the external links satisfied Wikipedia:External links, so I deleted them all. Details are given below. We need to find links of the "further reading" type, that provide more (and relevant) detail than is included here.
* A special issue of Progress in Biophysics & Molecular Biology that focuses on ultrasound and infrasound — requires purchase
* American Institute of Ultrasound in Medicine (Professional Association) — move to Medical ultrasonography
* Ultrasound Safety Issues  — move to Medical ultrasonography
* Radiology Web Site Directory  — nothing to do with ultrasound
* Ultrasound Job Outlooks — nothing to do with the topic
* Radiology Resources for Students and Professionals — nothing to do with ultrasound
* Ultrasound Can Affect Fetal Brain Development — move to Medical ultrasonography
* 3D Ultrasound Info - Includes sample images and studies — commercial site
* Yahoo email groups:- — discussion forums usually not recommended
— DavidMack 23:02, 4 July 2007 (UTC)
thread_title: Link clean-up

message: Does it seem odd to anyone else that there is more content regarding the risk and dangers of ultrasound for medical purposes than there are in the dedicated 'Medical ultrasonography' page? I thought that for the page on general 'Ultrasound', there should be more about the various uses of ultrasound in diagnostic medicine rather than several paragraphs on the risks of it.  Saket (talk) 04:40, 8 December 2007 (UTC)
thread_title: Emphasis on medical ultrasound risks rather that diagnostic use?

message: This article seems to be missing content on ultrasonic welding --Ozhiker (talk) 21:50, 13 July 2008 (UTC)
thread_title:  No Ultrasonic Welding? 

message: This info from User:Hellandback and available for wikification. LightYear (talk) 02:44, 17 October 2008 (UTC)
thread_title:  Ultrasonic effects during pregnancy 

message: Our article states:
:Ultrasound generator/speaker systems are sold with claims that they frighten away rodents and insects, but there is no scientific evidence that the devices work.[35] [36] [37]
I was previously of this opinion myself, but when I went to check reference 35 ( http://books.google.com/?id=vYGZs2A7S_IC&printsec=frontcover&dq=mouse+ultrasonic+repellent#v=onepage&q=ultrasonic&f=false ) I was surprised to discover that there is in fact strong evidence that they work. The cite actually seems to have the exact opposite sense to the claim in the article.
The cite, from Vertebrate pest control and management materials: 6th volume; Volume 1055 of ASTM special technical publication. discusses the difficulty of assessing such devices fairly, rather than their efficacy. However in passing it present the results of some experiments (e.g. the graph on page 11, Fig. 1) which pretty clearly shows a high degree of efficacy (about 80% reduction in rodent activity) at very high statistical significance.
Specifically, there are 9 control days and 9 treatment days on this graph. The very first treatment day showed much less rodent activity than most control days, but marginally higher rodent activity than the very lowest scoring control day. This lowest scoring control day, 7/30, is clearly anomalous; you can easily see that it is 3 to 4 s.d. below the rest of the control days.
Other than that, every single treatment day showed less rodent activity than the very lowest control day, and every single control day showed more rodent activity than the very highest treatment day. If we be permitted to put aside the first treatment day (or equivalently, the anomalous control day) as a special case, then the robust non-parametric significance level of this result is 7 x 10-6. Even if we do not disregard the first treatment day, the result still has a significance of about 72 x 10-6. I emphasise that this is a non-parametric result; looking at the size of the differences, which mostly are very large, it is clear that the if we turned the histogram bars back into numbers and did a parametric test the significance would be even more extreme. However that is unnecessary because even the non-parametric result is immensely strong.
Thus this result -- which comes from an experiment being put forward as an example of a good way to design these experiments -- is highly statistically significant. And one counter-example suffices to disprove a universal claim like  ... there is no scientific evidence that the devices work.
I also checked the other references. I was unable to read reference 35. Reference 36, "NAS; National Research Council (U.S.). Committee on Plant and Animal Pests. Subcommittee on Vertebrate pests, Robert A. McCabe, National Academy of Sciences (U.S.) (1970). Vertebrate pests: problems and control; Volume 5 of Principles of plant and animal pest control, National Research Council (U.S.). Committee on Plant and Animal Pests; Issue 1697 of Publication (National Research Council (U.S.))). National Academies. p. 92", http://books.google.com/books?id=uDorAAAAYAAJ&pg=PA92&dq=mouse+ultrasonic+repellent&hl=en#v=onepage&q=ultrasonic&f=false also does not support the claim! What it actually says about ultrasonics is:
:Ultrasonic (high frequency) sound repellents do not obviate the necessity for ratproofing.
The very next line notes that chemical repellents are also not completely effective. In other words, this resource is not claiming, as we do, that there is no scientific evidence that ultrasonic repellents work at all; rather, it is saying that they do work but (in the 1970s at least) are not 100% effective!!
I will leave this comment here for a few days for anyone else to comment, then I will completely change the offending line to say that they are proven to work, but are not completely effective. -- 202.63.39.58 (talk) 03:11, 26 March 2011 (UTC)
thread_title:  Rodent control 

message: The illustration of ultrasonic and infrasonic ranges uses the word "acoustic" for the bit between them. My understanding of the word was identical to the first sentence of the entry for "Acoustics" ie. "Acoustics is the interdisciplinary science that deals with the study of all mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound and infrasound."
True, "Audible sound" doesn't have as nice a ring (heh) to it, but isn't "acoustic" wrong in this context?
InelegantSolution (talk) 12:18, 1 March 2012 (UTC)
replies: text: Ah fair point. I was just thinking of the dictionary definition when I created it. Might be nicer to just use "Audible" but of course, then you have controversy about "audible to who/what?". Never going to get a completely unambiguous term. Can we get some more opinions about what sounds right to different folk? LightYear (talk) 22:25, 11 March 2012 (UTC)
thread_title:  Terminology in the first illustration 

message: Ultrasonics duplicates the contents of this article and any unique material from it ought to be merged. --Wtshymanski (talk) 13:25, 18 September 2012 (UTC)
replies: text: Agree. Merge any unique material and make Ultrasonics redirect.  — Preceding unsigned comment added by LightYear (talk • contribs) 05:33, 20 September 2012 (UTC)

text: Support. As the Ultrasound (disambiguation) page says, "Ultrasonic is an adjective referring to ultrasound." Also, for some reason Ultrasonic redirects to Ultrasound (disambiguation). A part of the confusion seems to come from confusion with http://www.ultrasonics.org/, which is the website of the Ultrasonic Industry Association. Regardless, merge. SchreiberBike (talk) 01:57, 26 September 2012 (UTC)
replies: text: Started merging, but stuffing in a large block of text reveals that there are other blocks that repeat other articles. Like many topics, this is a subject for a book-length treatment and this article should be an overview. --Wtshymanski (talk) 16:55, 28 September 2012 (UTC)

text: Oppose. The merger has a long history of deleting large quantities of content that he believes does not belong in his encyclopedia (WP:OWNERSHIP).  He also has a long history of allowing only minimal time for any proper discussion so that not too many editors have much opportuniuty to object. A merge proposal should stand for several weeks to allow proper concensus to occur. 86.166.70.84 (talk) 17:02, 28 September 2012 (UTC)
replies: text: Why two weeks?  Why not 15 days?  or 11 days? Or 5 years? Someone who's not yet been born might have an opinion, too. C'mon, you're making a mountain out of a molehill. Most people don't edit encyclopedias at all.People who don't look at articles don't care what happens to them. It only takes a week for a deletion, why would a much less significant change to the encyclopedia need excessive time for debate?  Nearly all editing decisions on the Wikipedia are *individual* decisions, with no bureaucracy involved at all.  And if you leave out vandalism reverts, my actual contributions are not extraordinary - in fact, rather humble compared to real Wikipedia enthusiasts. A curious argument to make, anyway. --Wtshymanski (talk) 18:00, 3 October 2012 (UTC)
replies: text: This point has been answered to the point of exhaustion in numerous other places.  I suggest that if you really cannot comprehend plain English then maybe you should seek the help of a responsible adult to point out to you why your continued tendatious editing is not appreciated. 86.150.66.174 (talk) 12:09, 4 October 2012 (UTC)
replies: text:  Sept 19 through Oct 4 is two weeks, and less if you only count article space not talk page nifnawing. --Wtshymanski (talk) 14:46, 4 October 2012 (UTC)
replies: text: And if you add the two weeks refered to above to the two weeks already expended, what do you get?  (Take your time).  You get the month that has been mentioed so frequently elsewhere as a minimum reasonable time to allow for opinions other than your own to be expressed.  86.150.66.174 (talk) 15:25, 4 October 2012 (UTC)
thread_title: Merge

message: Instead of an exhaustive catalog of applications, I'd like to see more of the fundamental physics described. How is ultrasound made and detected? What physical properties does it have taht make it useful? What are the limitations of ultrasonic techniques? When was ultrasound discovered?  When was ultrasound applied to industrial problems? And so on. --Wtshymanski (talk) 18:44, 28 September 2012 (UTC)
replies: text: I just expanded the TOC after adding info about wireless communications.  There's too much good application info in this article that is hard to find without a full TOC.Timtempleton (talk) 22:24, 23 July 2015 (UTC)
thread_title: Expansion

message: In some cases, people may hear sounds well above 20 kHz. Howard, Carl Q., Hansen, Colin H., and Zander, Anthony C., 2004, in "A Review of Current Ultrasound Exposure Limits" cite Schust, M., 1996 "Biological Effects of Airborne Ultrasound"/"Biologische wirkung von luftgeleitetem ultraschall” as saying that "The human ear may perceive auditory sensations up to at least 40kHz." 173.66.211.53 (talk) 01:17, 16 May 2013 (UTC)
thread_title:  Human Hearing Range 

message: "to distribute the cellulose fibres more uniform in the" = "uniformly" or "homogenise" Sorry but not allowed to edit page despite being logged in? Please delete once correctedBrobof (talk) 15:34, 16 September 2013 (UTC)
replies: text: . Your account must be confirmed/autoconfirmed to edit semi protected pages, see WP:AUTOC. — Reatlas (talk) 08:44, 17 September 2013 (UTC)
thread_title: Cleanup

message: please shows this ultrasound editing  page
41.78.73.252 (talk) 14:25, 11 August 2015 (UTC)
replies: text: Not done: as you have not requested a change.If you want to suggest a change, please request this in the form "Please replace XXX with YYY" or "Please add ZZZ between PPP and QQQ".Please also cite reliable sources to back up your request, without which no information should be added to, or changed in, any article. - Arjayay (talk) 14:30, 11 August 2015 (UTC)
thread_title:  Semi-protected edit request on 11 August 2015 

message: Reference 2 is a dead link Tpmcf (talk) 04:29, 14 April 2016 (UTC)
thread_title:  References 

message: Category:Australian inventions
59.101.71.20 (talk) 04:46, 21 July 2016 (UTC)
replies: text: Not done for now: why?  Cannolis (talk) 05:13, 21 July 2016 (UTC)
thread_title:  Semi-protected edit request on 21 July 2016 

message: Hello fellow Wikipedians,
I have just modified 10 external links on Ultrasound. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
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thread_title:  External links modified 

message: Under ==Processing and power== ===Physical therapy===, there is an extra /ref tag
Currently: | archive-date = 2007-04-12 }}</ref> for a pdf version with the author and date information)</ref>
Should be: | archive-date = 2007-04-12 }} for a pdf version with the author and date information)</ref>
 165.225.38.118 (talk) 00:31, 25 July 2019 (UTC)
thread_title:  Semi-protected edit request on 25 July 2019 

message: Add to Ultrasound Wiki page (https://en.wikipedia.org/wiki/Ultrasound), the fact that ultrasound disrupts the BBB and causes fatigue, headache syndromes
https://www.researchgate.net/publication/235923211_A_review_of_current_airborne_ultrasound_exposure_limits
Research has shown that airborne ultrasound
has the potential to cause nausea, fatigue, and headaches
(NOHSC 2002, OSHA 2004, Gierke & Nixon 1992, Acton
1974, Damongeot & Andre 1988, and IRPA 1984). 
There are no reports of hearing loss due to ultrasound exposure (Acton & Carson 1967, Knight 1968), although there is a
report of temporary threshold shift in subjects exposed to
frequencies of 18kHz at 150dB for about 5 minutes (Acton &
Carson 1967). JWAMD (talk) 19:48, 22 October 2020 (UTC)
replies: text: . It's not clear what changes you want to make.  Please make a precise request (and as a side note, I (and probably most readers) have no idea what "BBB" is).  –Deacon Vorbis (carbon • videos) 22:41, 22 October 2020 (UTC)
thread_title:  Semi-protected edit request on 22 October 2020 

message: Category:Australian inventions 203.30.15.60 (talk) 11:06, 9 May 2021 (UTC)
replies: text: Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. Run n Fly (talk) 15:48, 9 May 2021 (UTC)
thread_title:  Semi-protected edit request on 9 May 2021 

message: The phrase:
"Ultrasound has been used by radiologists and sonographers to image the human body for at least 50 years..."
requires the undisclosed knowledge of when the paragraph was written.
An objective time such as - "as early as the 1970's" is preferable. 46.19.85.80 (talk) 11:16, 5 March 2024 (UTC)
thread_title:  Relative time "for at least 50 years"