Tag: Biomedical measurements
-
5 Established Isolation Architectures for Medical Isolation Amplifiers
Medical isolation amplifiers provide an ultra-low conductive pathway between the input (patient) terminals and the output terminals and ground. This pathway provides what is called ohmic or galvanic isolation for a patient. In medical applications, this isolation is required for reasons of patient safety. The dc resistance between input and output terminals is typically on…
-
Biosignals Data Acquisition
Biological signals are often very minute and typically contain unwanted interference or noise. Such interference has the detrimental effect of obscuring relevant information that may be available in the measured signal. Noise can be extraneous in nature arising from sources outside the body, such as thermal noise in sensors or 60-cycle noise in the electronic…
-
Comparison of Imaging Modes – Ultrasound, CT & MRI
How the three imaging modalities compare? We examine each of the three diagnostic imaging methods as discussed in the following sections: Ultrasound Imaging Unlike other imaging modalities, ultrasound resolution and penetration depends on the center frequency and type of frequency selected. The resolution is spatially variant and depends on both the size of the active…
-
Key Considerations for Biopotential Measurements
Biopotential measurements are done using different types of specialized electrodes. The work of these recording electrodes is to couple the ionic potentials generated inside the body to an electronic instrument. Biopotential electrodes are classified either as non-invasive (skin surface) or invasive (for example microelectrodes or wire electrodes). Related: Types of Electrodes used in Medical…
-
Micrometer and Nanometer Biomedical Sensing Applications
The advancements in microtechnology and, in particular, nanotechnology are transforming the fields of biosensors, prosthesis & implants and medical diagnostics. In medical diagnostics, these devices are being employed in combination with optical biosensing for external, lab-on-a-chip, high throughput screening for analysing blood and other samples. Several companies and researchers are developing optically based nanotechnology applications…
-
Blood Glucose Sensors
The accurate measurement of blood glucose is essential in the diagnosis and long term management of diabetes. In this article, we discuss the use of biosensors for the continuous measurement of glucose levels in the blood and other body fluids. Glucose is the main circulating carbohydrate in the body. In normal individuals, the concentration of…
-
The Application of Echocardiography in Cardiovascular Diagnosis
The key application of ultrasound in cardiovascular diagnosis is echocardiogram. It utilizes M-scan technique in the imaging. In the echocardiogram, the movements of the valves and other structures of the heart are displayed as a function of time. The display also includes an electrocardiogram to provide more information on the heart. From the echocardiogram, the…
-
How Partial Pressure of Oxygen and Carbon dioxide in the Blood is Measured
The measurement of partial pressure of oxygen and carbon dioxide in the blood is one of the key physiological chemical measurements. The partial pressure of a dissolved gas is defined as the contribution of this dissolved gas to the total pressure of all dissolved gases in the blood. Hence, the partial pressure of a gas…
-
The Function of Impedance Pneumograph In Respiration Measurements
Impedance pneumography is an indirect method for the measurement of respiration. This measurement is performed by the impedance pneumograph which measures the respiratory volume and rate through the relationship between respiratory depth and thoracic impedance change. Impedance pneumography avoids burdening the subject with spirometers, tubes, and flowmeters; does not hinder respiration and has minimal effect…