Surgery – Diagnostic testing – Cardiovascular
Reexamination Certificate
2002-06-27
2004-06-29
Nasser, Robert L. (Department: 3736)
Surgery
Diagnostic testing
Cardiovascular
C600S485000
Reexamination Certificate
active
06755792
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an arteriosclerosis examining apparatus for examining arteriosclerosis, in particular, arteriosclerosis obliterans.
2. Related Art Statement
There is known, as a sort of arteriosclerosis, atherosclerosis that is arterial atheroma caused by deposit of lipid, such as cholesterol, on inner walls of arteries. Since atherosclerosis causes stenosis of arteries, it is also called arteriostenosis, or arteriosclerosis obliterans. There is known an inferior-and-superior-limb blood-pressure-index measuring apparatus as an apparatus for examining arteriostenosis. This apparatus is disclosed in, e.g., Japanese Patent No. 3,140,007 or its corresponding U.S. Pat. No. 6,355,000. The blood-pressure-index measuring apparatus includes two inflatable cuffs that are adapted to be worn on an inferior limb and a superior limb of a living subject, calculates, as an inferior-and-superior-limb blood-pressure index, a ratio of one of a superior-limb blood pressure and an inferior-limb blood pressure to the other, and examines arteriostenosis based on the thus calculated inferior-and-superior-limb blood-pressure index.
More specifically described, examination of arteriostenosis based on inferior-and-superior-limb blood-pressure index is effected by comparing the index value with a predetermined reference value. For example, in the case where an inferior-and-superior-limb blood-pressure index is calculated by dividing an inferior-limb systolic blood pressure by a superior-limb systolic blood pressure, if the index value is greater than 0.9, it can be judged that the subject does not have arteriostenosis and, if not, it can be judged that the subject is suspected of having arteriostenosis.
In many cases, arteriostenosis occurs to inferior limbs of living persons. Hence, the inferior-and-superior-limb blood-pressure-index measuring apparatus is used for the purpose of examining arteriostenosis of inferior limbs. In fact, arteriostenosis may occur to other regions of living persons. However, the examination based on the inferior-and-superior-limb blood-pressure index cannot be used to diagnose or identify in which region arteriostenosis is present.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide an arteriosclerosis examining apparatus which can accurately examine arteriosclerosis of a living subject.
The above object has been achieved by the present invention. According to a first aspect of the present invention, there is provided an apparatus for examining arteriosclerosis of a living subject, comprising a pulse-wave detecting device which detects a pulse wave from a first portion of the subject; a stenosis-related-information obtaining means for obtaining, based on a shape of the pulse wave detected by the pulse-wave detecting device, stenosis-related information that changes in relation with stenosis of an artery of a second portion of the subject that is located upstream of the first portion of the subject in a direction in which blood flows in the artery; and a stenosis judging means for making, based on the stenosis-related information obtained by the stenosis-related-information obtaining means, a judgment about the stenosis of the artery of the second portion of the subject.
If the artery located upstream of the portion where the pulse-wave detecting device is worn has stenosis, the shape of the pulse wave detected by the detecting device changes in relation with the stenosis. Therefore, the stenosis-related-information obtaining means obtains, based on the shape of the pulse wave detected by the pulse-wave detecting device, the stenosis-related information that changes in relation with the stenosis, and the stenosis judging means makes, based on the stenosis-related information obtained, a judgment about the stenosis of the artery located upstream of the portion where the detecting device is worn. Thus, the present apparatus may be used such that the pulse-wave detecting device is worn on each one of different portions of the subject so as to make a judgment about stenosis of an artery located upstream of the each portion, or may employ a plurality of pulse-wave detecting devices which are adapted to be worn on different portions of the subject so as to detect respective pulse waves and make, based on those pulse waves, respective judgments about stenosis of respective arteries located upstream of those portions. In either case, the present apparatus can identify an arteriostenotic portion of the subject.
A waveform of the pulse wave detected by the pulse-wave detecting device may be deformed by noise such as arrhythmia or physical motion of the subject. This pulse wave is not appropriate for use in making a diagnosis on arteriostenosis. If stenosis-related information is obtained based on the inappropriate pulse wave, an appropriate diagnosis cannot be made on arteriostenosis.
Hence, preferably, the stenosis-related-information obtaining means comprises means for selecting, from a plurality of heartbeat-synchronous pulses of the pulse wave detected by the pulse-wave detecting device, at least one heartbeat-synchronous pulse whose waveform has an identifiable characteristic point; and means for obtaining the stenosis-related information based on the selected heartbeat-synchronous pulse.
According to this feature, the stenosis-related-information obtaining means selects, from the heartbeat-synchronous pulses of the pulse wave detected by the pulse-wave detecting device, a heartbeat-synchronous pulse whose waveform has an identifiable characteristic point, and the stenosis-related information is obtained based on the thus selected heartbeat-synchronous pulse. The stenosis-related information obtained based on the heartbeat-synchronous pulse whose waveform has the identifiable characteristic point is accurate information, and the stenosis judging means makes, based on the accurate stenosis-related information, a judgment about the stenosis of the artery located upstream of the portion where the detecting device is worn. Thus, the present apparatus can make an accurate diagnosis about arteriostenosis.
According to another feature of the first aspect, the stenosis-related-information obtaining means comprises a sharpness-degree determining means for determining a degree of sharpness of each of a plurality of heartbeat-synchronous pulses of the pulse wave detected by the pulse-wave detecting device; and an average-sharpness-degree calculating means for calculating an average of the respective degrees of sharpness of the heartbeat-synchronous pulses of the pulse wave determined by the sharpness-degree determining means, and the stenosis judging means makes the judgment about the stenosis of the artery of the second portion of the subject, based on a degree of sharpness of at least one heartbeat-synchronous pulse of the pulse wave determined by the sharpness-degree determining means, when a comparison value which is obtained by comparing the degree of sharpness of the at least one heartbeat-synchronous pulse, with the average sharpness degree calculated by the average-sharpness-degree calculating means, falls within a reference range.
According to this feature, the stenosis judging means makes the judgment about the stenosis of the artery, based on an average one of respective degrees of sharpness of respective heartbeat-synchronous pulses of the pulse wave detected by the pulse-wave detecting device. It can be said that an average degree of sharpness is derived from a heartbeat-synchronous pulse whose waveform is not deformed by noise or arrhthmia. Thus, the present apparatus can make an accurate diagnosis about the stenosis of the artery located upstream of the portion where the detecting device is worn.
According to a second aspect of the present invention, there is provided an apparatus for examining arteriosclerosis of a living subject, comprising a first-pulse-wave detecting device which detects, as a first pulse wave, a pulse wave from a first portion of the subject; a second
Honda Takashi
Masuda Hiroshi
Ogura Toshihiko
Tampo Akira
Colin Medical Technology Corporation
LandOfFree
Arteriosclerosis examining apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Arteriosclerosis examining apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Arteriosclerosis examining apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3349540