Reviews and News on Ultrasound Machines

The medical ultrasound field plays an important role in preventive healthcare and diagnostic testing. As a result, the medical ultrasound community has joined forces to educate the public about the importance of medical ultrasound in healthcare.

While most people are familiar with ultrasound use during pregnancy, the general public is generally unaware of how ultrasound is used throughout other stages of life, and with various medical indications.

During the month of October, which is Medical Ultrasound Awareness Month, medical ultrasound professionals will plan special activities and educational materials to educate their patients, as well as the public, about how medical ultrasound works. Included in their educational programming will be ultrasound’s use in medical diagnoses, which areas of the body can be imaged with ultrasound, and the terminology related to medical ultrasound testing.

Medical Ultrasound Awareness month will:

* Educate the public about the certification process for those who perform medical ultrasound exams, and help them make informed decisions about their care;
* Inform the public about technological advancements in medical ultrasound over the past 50 years and how they have positively impacted the quality of healthcare;
* Introduce the public to professionals who specialize in this area of medicine, and educate students about potential careers in medical ultrasound; and
* Celebrate the profession of professional ultrasound imaging specialists.

Medical Ultrasound Awareness Month is a joint effort of the American Institute of Ultrasound Medicine (AIUM), the American Registry of Diagnostic Medical Sonographers (ARDMS), the American Society of Echocardiography (ASE), Cardiovascular Credentialing International (CCI), the Society of Diagnostic Medical Sonography (SDMS) and the Society for Vascular Ultrasound (SVU).

Over the past decade, pregnant women have been bombarded with advertising from “boutique ultrasound” services that promise to provide a “keepsake” ultrasound video of their baby. These commercial businesses, more like photography studios than medical facilities, go far beyond the standard, doctor-administered ultrasound previously offered during pregnancy. In fact, many women have started posting their baby’s ultrasound photos on Facebook and other social networking sites. Today’s photo-realistic images show much more detail than the standard ultrasound image of the past. Ultrasound videos can even facial features, movements and thumb-sucking.

This budding, yet controversial, business sector provides expectant families with photos, videos, and digital images of fetal ultrasounds. High-tech boutique-style ultrasound centers have been gaining popularity across the country, but it is beginning to cause alarm within the medical community. Many obstetricians believe these frequent, non-medical ultrasounds could be potentially harmful to both the mother and fetus.

Connecticut legislators are close to banning ultrasounds for pregnant women unless they are pre-approved for medical or diagnostic reasons. This action is in response to the growing number of “keepsake” ultrasound businesses in the state. While there are no conclusive studies to prove long-term injuries caused by excessive ultrasounds, the bill’s supporters contend that using ultrasounds as a form of “entertainment” is inappropriate and dangerous.

The FDA has also expressed concern about this growing practice, calling it an “unapproved use of medical devices”.

Part of the reason for the growth in commercial ultrasound business is recent improvements in the technology over the past 5-7 years, which have improved the photo quality of the images, but like any other medical procedure, it comes with a certain amount of risk. Most physicians agree; conducting medical procedures outside of a medical setting is never a good idea.

Any medical imaging specialist will tell you, the most important part of medical ultrasound scanners is the “transducer probe”. This is the part of the machine that converts sound waves into electronic signals, and back again. In most cases, the transducer probe is made out of piezoelectric materials, which are designed to produce electrical voltage when stressed and also deform when external voltage is applied.

While this type transducer probe is considered the industry standard, a better type of probe can be made using a different principle. The principle of the “condenser microphone”, also known a capacitive transducer, uses a back plane with a thin membrane that vibrates. The only issue with bringing this type of transducer to market has been their need to contain enormous electrical fields, which has been difficult to accomplish. However, researchers have made progress recently by using the same production techniques often used in making microelectronics. It won’t be long before you begin to see capacitive transducers being routinely offered with medical ultrasound machines. This development should dramatically improve the sharpness of images produced by ultrasound equipment.

These capacitive micro-machined ultrasonic transducers (CMUTs) will overcome many of the limitations on existing ultrasound equipment, allowing new applications for ultrasound transducer technology in the field of medical imaging and treatment. CMUTs will bring the fabrication technology of standard, integrated circuits into the field of ultrasound medical imaging.

In terms of bandwidth, high frequency applications, and compatibility with newer imaging models, these devices are expected to be the next generation in acoustic medical imaging. Recent advances in micro-fabrication will make it possible to introduce these new silicon based electrostatic transducers within a few years, when they are expected to compete in performance against the standard piezoelectric transducers.

An Endoscope is a long thin tube with a miniature camera lens fixed on the tip of the tube, and a light source at the other. It is inserted in the body cavity of a person in order to view the inside of the intestines, oesophagus etc, and a magnified image of the relevant area is transmitted to a viewing monitor. The Endoscopy equipment consists of a control head and a flexible long tube containing several other tubes transmitting light, air, water or even suction.

Endoscopes pertaining to the specific parts of the body are developed in order to customize the procedures with regards to ailments relating to the abdominal cavity, lungs, bladder, uterus, nasal, rectum etc. For example, a gastro scope is used to view the insides of the stomach intestines; a laparoscope is used to look in anything from the gall bladder to the women’s reproductive organs etc.

Initially endoscopic instruments were only used to take images of the organs and intestines, today, live color video can be viewed and all aspects of the affected area can be diagnosed first hand with the use of fiber optic instruments encasing thousands of mirrors and lens in a very tiny, flexible and compact tube.

With the advancement of modern technology and the development of the endoscopic equipments, these are also used to take a biopsy, suck formation of pus, and also perform surgeries such as hernia, fallopian tubal ligation, laser surgeries etc.

The patient is usually given anesthesia for sedation and also given pain killing medications to avoid soreness or discomfort. The procedure is hardly invasive, although in some cases it requires tiny incisions depending on the requirement. After the procedure the patient is kept in observation for few hours till the effect of the anesthesia wears off and is further checked for any discomforting effects or reactions.

Pulse Wave Doppler is an imaging technique based on the ultrasound imaging principle. Ultrasound images of blood flow, either by Color Flow, Power Doppler, Continuous Wave, or Pulse Wave Doppler all essentially give the movement of the blood. Using any of the methods details about the heart circulation and blood can be found. In the technique of Pulse Wave Doppler (PWD) a series of electrical pulses are transmitted to visualize the movement of blood.

The electrical pulses sent give the echoes; depending upon the echoes the blood flow is calculated. By the Doppler Effect it can be clearly differentiated among the blood vessels and the body tissues. As the echoes from the stationary type body tissues are constant and do not change from pulse to pulse while echoes from the moving objects like blood changes from time to time with every pulse. These differences in the flow can be directly measured by the time difference or in terms of the phase difference from which the Doppler Frequency is determined.

In Pulse Wave Doppler imaging the electrical signals are sent in the form of pulses. The transmission of the pulsated signal is produced by the oscillators, which changes its voltage according to the resonance frequency. Short duration pulses of the ultrasound frequency are sent with a specific frequency, which is known as pulse repetition frequency (PRF). In the duration of the pulse transmission echoes continuously returns to the receiving transducer, but all the receiving signals are not viewed. The receiving transducer has its fixed frequency to open the gate for receiving the signals. The shift in the frequency from the pulse transmission is to allow the estimation of the Doppler Frequency Shift.

Pulse Wave Doppler is a famous technique used for imaging the blood flow by the electrical pulse methods and the technique has its own instruments, which are used to measure the blood flow.

Power Doppler Imaging can be abbreviated as PDI, is an imaging technique based on the ultrasound technology. PDI is based on the Doppler Effect for measuring different parameters of the body. Doppler Effect correlates the velocity of the observer and the source in a medium, thus it is a procedure to find out the relative effect of the motion of the observer, source and medium. Power Doppler Imaging is a technique based on the Doppler Effect to find out the relative velocity of the blood which moves towards and away from the measuring probe.

With PDI the frequency shift of a particular blood flow on a heart valve is calculated. The speed and direction of the flow is also determined though this technique. The Power Doppler Imaging is typically used for cardiovascular studies which involves sonographic study of heart and vasculature system. These cardiovascular studies are essential in numerous areas such as determining reverse direction blood flow in the liver portions.

The Power Doppler Imaging is the non directional Doppler. The Doppler shift produced by these imaging methods come in the audible range and is represented audibly by stereo speakers. These speakers produce a distinct synthetic, pulsating sound.

Power Doppler Imaging when compared with conventional imaging methods such as color flow Doppler proves its utility in manifolds. Power Doppler Imaging methods usually visualize the morphological effects minutely by leaving the artifacts like echoshadowing and aliasing. In some of the cases of distal occlusion color flow Doppler has failed to depict the proper blood flow details, but power Doppler imaging gave the pertinent readings.

Power Doppler Imaging is a useful sonographic technique to determine the problems related to blood flow and can examine nicely some of the hypoplastic and stenosed arteries. The current inventions are making it more useful for the ultrasonic applications.