Ultrasound machines used for diagnostic imaging or therapy emit ultrasound (high-frequency) waves that penetrate different types of tissue in the body.

This kind of diagnostic equipment produces images without using harmful radiation as with x-rays. Due to the fact that ultrasound machines do not produce any ionizing radiation, it is very safe for human beings. With their own easily obtainable and affordable ultrasound machines, doctors’ offices and clinics are able to examine various organs in the body on-site without having to send patients to the hospital or expensive medical imaging centres.

Compared to magnetic resonance imaging (MRI) and computed tomography (CT), ultrasonography is relatively inexpensive, and the equipment is very portable. In today’s healthcare environment, ultrasound can be considered the most cost-effective modern imaging modality.

What is UltraSound?

Ultra- is used to describe sound waves as in “ultrasound”, which exceeds a frequency that a human ear can detect. Normally, a human ear can hear approximately 20 hertz to 20,000 hertz (1 hertz is one cycle per second). Ultrasound, used for diagnostic imaging or therapy, can be employed to analyse or treat medical conditions. It applies cyclical sound pressure pulsed at a frequency higher than the human ear can detect, or 20,000 hertz, hence the name ultrasound.

Components of an Ultrasound Exam

Sonographers & Ultrasound Technologists are trained operators of ultrasound machines.

• Central Processing Unit (CPU) – The ultrasound machine’s brain. The computer contains the microprocessor, memory, amplifiers and power supplies for the microprocessor and transducer probe. The CPU sends electrical currents to the transducer, which in turn sends electrical pulses that bounce off of the target and return echoes. The CPU calculates the location of thousands of points of echo origins to produce an image for output such as a monitor, a printer, a network drive; or a disk.

• Transducer Pulse Controls – The transducer pulse controls can set and vary the frequency, amplitude and duration of the ultrasound pulses. Electrical currents are applied to the piezoelectric (PZ) crystals in the transducer/ probe^, as selected by the operator.

•Display – The display turns processed data from the CPU into an image. Sonogram images have typically been black-and-white, but newer ultrasound machines can produce colour Doppler images.

•Keyboard/Cursor – Ultrasound machines have a keyboard and a cursor. The keyboard allows the operator to add notes and to take measurements of the image; the mouse enables the operator to interact with the ultrasound machines software.

•Disk Storage – The processed data and/or images can be stored. Storage can include hard disks, compact disks (CDs), digital video disks (DVDs), or a network drive. Most of the time, ultrasound machines store data with the patient’s medical records.

•Ultrasound Printers – Most ultrasound machines have thermal or digital printers connected to them. Ultrasound images are in motion (real-time), but a still/ frozen image can be captured at any point and sent to the printer for printing.

Ultrasound Uses

Ultrasound machines can be used on many objects, typically to penetrate them and evaluate the reflections that occur, or to supply concentrated energy. The ultrasound reflection signature can detail the internal structure of the medium.

The most well-known exam performed on ultrasound machines is the obstetric ultrasound exam (imaging of the fetus). While many people relate this applied science with obstetrics only, there are many other applications for ultrasound technology.

Medical diagnosis, which is crucial in disease treatment, has been a chief cause in the overall improvement of healthcare outcomes. Ultrasound machines have given a huge boost to medical diagnosis. Ultrasound can visualize problems in a patient’s organs and other tissues by bouncing ultrasound waves off of them and using a computer to plot the many points received and portrays these plots into images on a monitor or print them onto thermal paper.

Nowadays ultrasound is available in small offices and healthcare clinics offering private ultrasounds. Within the last decade, many endocrinologists and otolaryngologists have turned to perform ultrasound exams in the comfort of their own offices. Identifying and diagnosing many ailments using ultrasound imaging has steeply declined our death rate from a variety of diseases and conditions.

Other applications include musculoskeletal (imaging of muscles, ligaments and tendons), endocrinology and otolaryngology (thyroid, salivary glands, and lymph nodes), ophthalmic ultrasound (eye) scans and other superficial structures such as breast and testicles.

Ultrasound is also increasingly being used in trauma and first aid cases by (the likes of) EMT response teams. Because of the real-time nature of ultrasound, it is often used to guide interventional procedures such as fine-needle aspiration FNA or biopsy of masses for cytology or histology testing in the breast, thyroid, liver, kidney, lymph nodes. Vascular scans are possible with the use of Doppler to display blood flow. Doppler is also being used to evaluate the blood flow of organs and cancerous regions.

How an ultrasound is done?

Ultrasound imaging might appear simple, but it is a complex medical procedure that requires prior training. The potential health risks that generated high-frequency waves can produce damaging the body tissue if exposure is too lengthy to warrant this. As such, only professional doctors and registered diagnostic medical sonographers with experience in their field of expertise can correctly regulate the duration of an exam.

Is Ultrasound Safe?

Loudness is measured in decibels (dB) not frequency. The loudness at which medical ultrasound waves are applied is less than 120dB. Ultrasound frequency is an inaudible 20,000 hertz. Yes, it’s safe, except:

•Excess of 120 dB may lead to hearing loss.

•Excess of 155 dB may harm the human body due to heat.

•Exposures above 180 dB may lead to death.

When applied by trained ultrasound technologists or sonographers, ultrasound machines are generally safe with no known risks to patients because ultrasound machines do not use mutagenic ionizing radiation.

If applied at length or at higher than diagnostic power, there potentially could be three effects created by ultrasonic energy: These could be enhanced inflammation; heating of soft tissue from molecular friction; and/or production of microscopic bubbles in living tissues which creates a distortion of the cell membrane.

When it comes to ultrasound, machines of this complexity are only to be used by qualified sonographers and ultrasound technicians or sonogram machine operators who are experts in medical ultrasound. Machines are very expensive and highly advanced.