Image analysis – Applications – Biomedical applications
Patent
1994-12-23
1997-02-11
Johns, Andrew
Image analysis
Applications
Biomedical applications
382286, G06K 900
Patent
active
056029357
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a bone morphometric method and a bone morphometric apparatus. More specifically, the present invention provides a bone morphometric method capable of measuring the pattern of the quantity of radiation transmitted through a sample bone, among bones suitable for measurement including a radius and a metacarpus, obtained from an image based on an image formed by irradiating the sample bone with radiation and measuring the transmitted radiation and of performing rational and accurate assay of the sample bone in terms of bone assaying parameters, particularly, by cancellate bone assaying parameters, and a bone morphometric apparatus for carrying out the same bone morphometric method.
BACKGROUND ART
The morphologies of human bones are measured to assay the growth and aging of bones, to diagnose and determine the degree of progress of bone diseases such as osteoporosis and osteomalacia, or to confirm a therapeutic effect.
Human bones are classified into cortical bones and cancellate bones. Cortical bones have dense bone structures having the shapes of pipes. Representative cortical bones are the shafts of the long tubular bones of the extremities.
Cancellate bones have mesh structures of osteocytes and are the epiphyses of long tubular bones, vertebrae, carpal bones, heel bones, anklebones, tarsi and such. Osteocytes of cancellate bones, as compared with those in cortical bones, have large areas in contact with soft tissues including blood vessels. Therefore, the progress of metabolism of cancellate bones is rapid and hence the progress of bone diseases in cancellate bones or changes in the state of cancellate bones caused by therapy are rapid.
MD, photon absorptiometry and radioscopy are used in generally known bone morphometric methods. MD measures density distribution in a roentgenogram of a sample bone, produced on an x-ray film by irradiating a sample bone with X-rays, by a microdensitometer (Kotsu Taisha, Vol. 13, 00. 187-195 (1980) and Kotsu Taisha, Vol. 14, pp. 91-104 (1981)), photon absorptiometry irradiates a sample bone with gamma rays and measures the quantity of transmitted gamma rays with a detector, and radioscopy irradiates a sample bone with X-rays and measures the quantity of transmitted X-rays with a detector.
MD is easily applicable to bone measurement and has progressively become prevalent because MD uses x-ray photographs that can be readily produced by the widespread x-ray photographic apparatuses which are widely used for diagnosing bone fractures.
These known bone morphometric methods, however, require drawing work for specifying a reference measuring line and a plurality of ROIs (regions of interest) near the reference measuring line on the x-ray photograph of a sample bone and it is difficult for even the same examiner to specify the same reference measuring line in examining the change in the sample bone and, consequently, accurate observation of the change in the sample bone cannot be achieved; that is, the ROI of the same sample bone cannot be accurately reproduced on each of a plurality of x-ray photographs of the same sample bone and, particularly with cancellate bones, the BMD (bone mineral density) varies widely with the variation of ROIs.
For example, in the SPA method (single photon absorptiometric method), in which a portion at a position along the bone equal to 1/6 of the length of the radius or 1/10 of the length of the ulna is measured, an operator measures the length of the radius or the ulna with a measure, puts a mark on the skin at a position corresponding to a measuring part, and then adjusts the forearm so that the forearm extends perpendicularly to a scanning direction in specifying a region of interest hereinafter referred to as an ROI ("Kotsu Mineraru Sokutei to Kotsu Soshyo Shyo", Medical Review K. K. (1989)). Therefore, the accurate reproduction of the ROI cannot be achieved due to errors in measuring the length of the radius or the ulna with a measure, and errors in determining the position to be marked, and th
REFERENCES:
patent: 4903203 (1990-02-01), Yamashita et al.
patent: 5138553 (1992-08-01), Lanza et al.
patent: 5228068 (1993-07-01), Mazess
patent: 5365564 (1994-11-01), Yashida et al.
patent: 5426709 (1995-06-01), Yoshida et al.
"Assessment of bone density in the distal radius with computer assisted X-ray densitometry (CXD)," part of the program summary of The Second Japan Osteoporosis Research Conference by the Japan Osteoporosis Foundation on Nov. 19 and 20, 1993. Program publish on Oct. 30, 1993, Seo et al. p. 105.
"Single Photon Absorptiometry," Bone Mineral Measurement and Osteoporosis, K. Yamamoto, pp. 55-63. (no date).
"A Computer-Assisted Method for the Study of the Trabecular Bone of the Distal Radius on Conventional Radiographs," Journal of Digital Imaging, by Donatella Trippi et al, vol. 6, No. 2 (May) 1993; 140-147.
Chen Dunhao
Yoshida Makoto
Johns Andrew
Teijin Limited
LandOfFree
Bone morphometric method using radiation patterns along measurin does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Bone morphometric method using radiation patterns along measurin, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bone morphometric method using radiation patterns along measurin will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-349088