Awake Surgery Tool Intraoperative Examination Monitor for Awake Surgery

Practical application of language function monitoring system while operation (IEMAS),
which is shown an integrated heterogeneous biological information IEMAS (Intraoperative Examination Monitor for Awake Surgery)

What’s IEMAS?

To save a patient from brain disorder Development of testing equipment which lower the risk of sequela after a brain tumor operation. Tokyo Women’s Medical University, Yasuhisa-KOKI Co., Ltd. Iwate Medical University, Aster Electric Co., Ltd.

Based on the support from Ministry of Economy, Trade and Industry, we have developed the IEMAS jointly with Tokyo Women’s Medical University and Yasuhisa-KOKI Co., Ltd. since 2011 and have started to sell since Oct. 2015.

What's the operation under waking? Since the high order functional sites are asleep as well when they are given general anesthesia, there is no way to know the site. Therefore, he/she is made awaken from the general anesthesia and is performed an operation only by using tranquilizer and applying a local anesthesia The brain itself does not feel pain.

Result According to clinical evaluation, we can identify the high order functional sites of patient and we can lower the risk of sequela after enucleation.

Effort in the project for business solution

Problem : Difficulty of the operation near “high order functional sites” of brain

When we have a small injury at brain in an operation, depending on the location of injury, we won’t be able to speak, read words, or calculate. These locations in brain are called “high order functional site”

Since the locations of high order functional site are different with each person, the doctor have to perform an operation as he/she check the precise location after he/she make the patient awaken from anesthesia. (Operation under waking)

Practically, the operating surgeon numb a part of brain with gentle electrical stimulus for a few seconds.

At the timing, the doctor make the patient read a word or say the name by showing the picture of object.

When the patient can say correctly, the doctor can confirm that the numbed part is not high order functional site. (High order functional test while operating) However, it is hard to synchronize the timing for the test. And it is not easy for the doctor to judge if the patient says correctly.

In addition to this, when electrical stimulus is done for a long time or done repeatedly, a bad effect might be had on the brain of patient.

Therefore, only a limited hospital can do the high order functional test while operating.

Solution : IEMAS is the medical equipment which provides the following functions at the high order functional test under operation.

(1) IEMAS shows a word or a picture to the patient at the right time and more visible.

(2) IEMAS shows all the information to the operating surgeon after consolidating in order for him/her to judge correctly.

(3) These information are recorded and we can reconfirm the result of test anytime. Therefore an unnecessary and a repeated operation can be avoided. By using IEMAS, the high order functional test can be done in many hospitals.

Aster Electric Co., Ltd. began manufacturing medical equipment since 1995 and develops and manufacture medical equipment for testing mainly at present.

Yasuhisa-KOKI Co., Ltd. has designed and developed the trial product ordered by university or institute of private company since its establishment from 40 years ago

The contents of research and development are shown in the following materials. And we continue to develop them aimed at the end of next year.

Detail content of medical research is shown below.
The URL of IEMAS made by Tokyo Women’s Medical University

Article about IEMAS written by Innervision is shown below.


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