The present invention relates to a satellite based communications system for transmitting medically related images from one or more remote locations to a central station and more particularly, to a system and method for converting radiological digital images into a radio signal for transmission to a central station, then at the central station converting the signals back into video or printed images for analysis, all within a limited time.
The current clinical practice for mammography depends on a batch-mode diagnostic procedure. This batch-mode operation consists of end-of-the-day collection of data representing each patient's examination at the screening site and then transferring them via surface transportation to the radiologist's location to be loaded on the mammography viewer for the start of the detection and diagnosis process. Typically, it takes less than five minutes for the radiologist to view all images from a single patient exam before deciding whether to view past year examinations and request a magnification view of suspicious areas. The batch approach inherently does not take advantage of the five minute turnaround in which a radiologist can interpret an examination and provide a diagnosis or request that more images be taken. If the images could be evaluated as they are produced, the reader could respond with the examination results while the patient is still at the examination site. As a result, the current problem, in that about 40 percent of patients do not return for follow-up exams, would be solved because the reduced delay between image collection and interpretation so that the need for further imaging is identified before the patient departs the facility. There exists a need to conduct remote radiological exams and to provide results of the exam while the patient is still available for additional exams.
Digital radiological images typically contain a high volume of data bits. To accomplish remote imaging the high volume of digitized radiological image data must be accurately transmitted via satellite within a short period of time. Systems for transmitting, via satellite, medically related images from remote stations to a central station are not adapted to handle the high volume of data needed for applications such as remote mammography examination. For example, mammography requires high resolution imagery, usually to within a 50 micron diameter. When converted to digital images, such high resolution mammography films require digitization of about 256 million bits per image. Consequently, the ability to transmit these high volume digitized images is limited because most present day communication protocols are designed for low volume data transmissions.
The data transmission limitations of the present system also impede the possibility of interactive communications between the remote station and the central diagnostic site. By way of illustration, high resolution mammography films require digitization of about 256 million bits per image and breast mammography typically requires four images per patient; correspondingly, one giga-bit of image data is transmitted per patient. Present systems for transmission of medical data cannot transmit this volume of information within, for example, a 10.5 minute window deemed necessary for interactive communications between the remote site and the professional located at the central diagnostic site.
The American College of Radiology and National Electrical Manufacturers Association developed a communications protocol for digital radiological images called Digital Imaging and Communications in Medicine (DICOM). DICOM is a specification of vendor-independent data formats and data transfer services for digital medical images. It was designed to ensure compatibility at the data level between the various manufactures of equipment for handling digitized images. This standard is used extensively in the industry.
The Extended Transmission Control Protocol/Internet Protocol, Extended (TCP/IP), was developed by the Network Working Group, of the Internet Engineering Task Force, and published in May 1992 by V. Jacobson, R. Braden, and D. Borman. It is an Internet based communications protocol designed to tolerate unreliable sub networks. This standard is used in the industry.
It is thus desirable to provide a satellite communication system utilizing a standard digital format such as DICOM and the Extended TCP/IP protocol so as to enable a remote station to provide high resolution medical images to a central diagnostic station within a time-frame to provide an effective interactive medical exam.