He/Ne laser irradiation produces various shape changes and haemolysis in erythrocytes. Under total absorption conditions, after correcting for the reflection from the surface, blood samples were exposed to various intensities of laser light. The upper limit of these intensities, at which the erythrocytes maintain their normal characteristics, has been used to develop safety levels for the various organs of subjects of varying complexions, assuming that even the cells below the skin layer are not damaged by laser exposures. Depending on the complexion these levels show considerable variations for various organs. © 1984 IFMBE.

A. Periasamy

LASER BEAMS - EFFECTS

Lasers, Gas

LIGHT - REFLECTION

Radiation effects

Erythrocytes

hemolysis

Biological materials

blood and hemopoietic system

cell shape

erythrocyte

HELIUM NEON LASER

Human

human cell

laser

normal human

radiation exposure

RADIATION SAFETY

reflectance

therapy

Accident prevention

Dose-Response Relationship, Radiation

Lasers

safety

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Determination of safe exposure levels of He/Ne laser light to the human body by means of erythrocyte irradiation studies

Medical & Biological Engineering & Computing

Time-average speckle interferometry has been applied to obtain displacement patterns on the chest wall produced by cardiac action, in the absence of breathing, during various phases of the cardiac cycle. This has been achieved by an electronic shutter, controlled by the electrocardiogram of the subject. The recorded holographic plates processed under identical conditions are scanned by the pointwise method to obtain the absolute displacements at various locations corresponding to the activities of the various cardiac chambers and values. These data are transformed to a 40 × 30 matrix by an interpolation method and, from this, three-dimensional displacement plots are reconstructed by an IBM PC/AT computer. These patterns shown the displacements over the entire cardiac area corresponding to the activities of various regions during the cardiac cycle. The apex and aortic valve areas show the maximum displacements during the systolic phase. During the diastolic phase the activities over the low pressure atrial regions are also observed. The results obtained outline the functional details of the normal heart and the activities over various areas are in agreement with that of other noncontact techniques. © 1991 IEEE

IEEE Transactions on Biomedical Engineering

Reconstruction of Sequential Cardiac In-Plane Displacement Patterns on the Chest Wall by Laser Speckle Interferometry

A noninvasive and noncontact technique based on the principle of laser speckle interferometry has been developed to record the cardiac displacements observed on the chest wall. These displacements are then reconstructed in the form of three-dimensional plots, during the P, QRS and T-waves of the ECG. A comparison of these patterns shows that the mechanical activity of each region varies significantly during these phases of cardiac cycle. As these displacements depend on the clinical status of the heart, its use with a cardiac patient shows the functional changes of the affected regions in the form of alteration of these patterns. © 1989 IFMBE.

Three-dimensional reconstruction of cardiac displacement patterns on the chest wall during the P, QRS and T-segments of the ECG by laser speckle inteferometry

Development of an optical fibre technique for He-Ne laser screening of human body and its comparison with the integrating sphere method

Clinical Hemorheology and Microcirculation

Erythrocytes sedimentation profiles as determined by He–Ne laser. III. Effect of various laser irradiations1

Mechanics of Materials

19th Annual meeting of the society of engineering science, Inc. October 27–29, 1982, at the University of Missouri-Rolla, Rolla, MO, U.S.A.

An integrating sphere technique has been applied to assess the reflectivity of different skin sites on the body, in male subjects of various complexion and of differing form. The measured reflectance and absorbance with helium-neon laser is shown to vary with skin colour, tissue composition and the blood flow through the organs. © 1981 IFMBE.

Helium-neon laser screening of human body

The Biomedical Laser

Safety with Biomedical Lasers

Journal	Medical & Biological Engineering & Computing
Publisher	Kluwer Academic Publishers
ISSN	01400118
Open Access	No