Investigation of different operating modes of ultrasonic annular array used in ophthalmology

M. Urnavičius, E. Jasiūnienė, R. Raišutis, O. Tumšys, A. Paunksnis

Abstract


The early-stage diagnosis of malignant tumours in eye is very important in ophthalmology in order metastasis of cancer could be prevented and the human life could be saved. Ultrasonography of eye is used already for some time and as it possesses no risk to a patient health it can be repeatedly performed for following of the disease progression.

In order to get as much as possible valuable information about the tumours and their structure it is necessary to create new methods and instruments for extraction of qualitative and valuable information from the received ultrasonic signals. In order to overcome limitations of the existing equipment the new knowledge concerning interaction of ultrasonic waves with intraocular tissue and back-scattering from the tissue affected by the tumour are necessary to be collected. For example, for optimization of the design and operation performance of ultrasonic annular arrays, numerical simulation can be performed.

The objective of this research was to investigate using CIVA software different possibilities of beam focusing in eye using on ultrasonic annular array and to find the optimal solution, which can be used in practice. The ultrasonic fields focused at different distances from the transducer are presented. The propagation of the ultrasonic wave in the eye with tumour and without has been simulated. The simulated and experimental B-scans of the healthy eye and the eye affected by tumour are presented as well. The presented results demonstrate that it is possible to locate malignant tumours in the eye using the optimised ultrasonic annular array.

http://dx.doi.org/10.5755/j01.u.66.4.1027


Keywords


ultrasonic imaging; annular array; CIVA

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