Technology Used in Medical Equipment
Canon uses its original optical and digital imaging technologies to supply devices that support digitization and networking in the field of medicine, such as digital X-ray systems and ophthalmic equipment.
Flat Panel X-ray Detector
Lending Strong Support to X-Ray Diagnosis
Medical diagnosis based on X-ray images is yet another field where digitization is making significant inroads, eliminating the need for film and facilitating on-screen diagnosis. In 1998, Canon launched CXDI-11, the world's first digital radiography system that featured a proprietary-developed X-ray image sensor. Since then, we have remained the leader in this field, continually expanding its lineup of related products in response to ever-diversifying demand for X-ray diagnosis solutions.
Static Digital Radiography System
X-ray imaging, vital to medical diagnoses, are progressively moving toward digital and online technologies. The Canon CXDI series, which incorporates the company's LANMIT*1 (Large Area New MIS Sensor and TFT) X-ray image sensor, is a digital radiography device that makes possible the acquisition of high-resolution medical image data with a low radiation dose.
The flat-panel LANMIT is made up of a scintillator on top of an optical sensor. It includes five layers, such as layers of scintillator and amorphous silicon. X-rays passing through the human body are converted into visible light by the scintillator, and then directly read by the optical sensor. Using cesium iodide (Csl), which has high light-conversion efficiency, the scintillator makes possible both high-resolution imaging and low X-ray dosage.
Noise reduction was a major issue during development, but Canon overcame it by developing dedicated components such as ICs, signal processing circuits, and power supplies. The result was a large, low noise detector with 43 x 43 cm imaging area and 7.2 megapixel resolution.
Scanned X-ray images are displayed on screen in a mere 3 seconds. The system uses a standard interface and control software that supports the latest medical data transmission standards, making it possible for scanned images to be shared within medical facilities via networks, or transferred to external institutions. This device is utilized in the telemedicine and emergency treatment fields.
- *1 LANMIT (Large Area New MIS Sensor and TFT)
Canon began research and development of the LANMIT in 1993, and in 1998 released the world's first digital radiography system to incorporate it (the CXDI series).
Dynamic / Static Digital Radiography System
Equipped with the company's newly-developed X-ray image sensor capable of capturing dynamic images, CXDI-50RF. caters for both dynamic imaging and the capture of high-quality static images.
Thanks to this dual capability, the CXDI-50RF can be used not only to diagnose problems in areas such as the chest and limbs using regular static images, but also to monitor moving image of the digestive system and other internal organs, taking static radiography images as required.
CXDI-50RF is also lightweight and portable, in spite of its large imaging area. The wealth of designing and development expertise acquired in the field of portable imaging sensors enabled Canon to realize a portable digital radiography system that provides for both static and dynamic images in a single, handy package. The CXDI-50RF can be carried about with ease, allowing for highly-flexible, highly-convenient operation. For example, after it is used with a bucky table for barium study of the digestive system in the morning, it can be transferred to an upright stand system and used for general chest examination.
Wireless Digital Radiography System
The CXDI-70C Wireless / 80C Wireless meet the needs of clinical sites by enabling wireless transmission of imaging data to computers. Removing the sensor cable makes the device more portable and user-friendly. It can be used not only in general radiography rooms, but also at bedsides or operating rooms with less stress for both X-ray technicians and for patients.
The compact size and light weight*2 were accomplished by reducing the electricity consumption during data output from the detector and designing a new, slim, 7mm battery pack. The product's structural elements are made with strong composite materials, providing both size and weight reductions while continuing to ensure the product's reliability. These improvements are what made it possible for Canon to develop both the thin and large-size 70C Wireless,*3 suitable for chest and abdominal imaging, and the small-size 80C Wireless,*4 which is optimal for use in the X-ray imaging of children and infants.
Improved image resolution is vital for accurate diagnosis. Canon has developed high-sensitivity and high-resolution flat panel detectors with miniaturizing pixels from 160µm to 125µm. In addition, aiming for less invasiveness for patients and high image quality for diagnostic use, Canon has adopted cesium iodide (Csl) highly-efficient scintillators for low dose X-ray imaging, which places less burden on patients, and high-quality imaging suitable for diagnostic use.
The increase in pixels due to increased resolution, however, creates a greater transmission load. In order to resolve this problem, Canon has developed new highly efficient image distribution methods and adopted IEEE802.11n, a high speed wireless LAN transmission standard. As a result, it became possible to show preview images in approximately three seconds and high-resolution images in approximately five seconds. This contributes to speedy diagnosis.
- *2 CXDI-70C Wireless: 3.4kg (including battery) / 80C Wireless: 2.3 kg (including battery)
- *3 CXDI-70C Wireless: Effective scanning size 350 x 430mm / External dimensions 384 (width) x 460 (depth) x 15 (thickness) mm
- *4 CXDI-80C Wireless: Effective scanning size 274 x 350mm / External dimensions 307 (width) x 384 (depth) x 15 (thickness) mm
Mydriatic / Non-Mydriatic Hybrid Digital Retinal Camera
Single Device Supports Both Mydriatic & Non-Mydriatic Retinal Examination*5
Canon, with its solid track record in the eye examination devices industry, has introduced CX-1, the company's first retinal camera*6 to combine mydriatic and non-mydriatic functions in a single device.
In the past, retinal cameras supporting both types of examination have required special optical systems and sensors for non-mydriatic retinal examination - that is, without dilating the pupil - resulting in highly complex retinal camera designs. In response, Canon integrated optical technologies acquired over many years of experience in the development of SLR cameras, with cutting-edge expertise in the fields of digital imaging and retinal camera technology, to develop CX-1 - a compact, hybrid retinal camera that is uniquely Canon. In addition to high sensitivity and low noise levels, the CX-1 utilizes proprietary image processing technologies to make possible higher resolution and better image quality than ever before, contributing to improved accuracy in diagnosis.
The CX-1 is equipped with five different photography modes, including Color, Red-Free, and Fundus Autofluorescence (FAF). And as the operator can switch between these modes with a single touch of a button on the operation panel, the speed and overall efficiency of retinal image capture is greatly increased. The non-mydriatic, FAF mode of operation in particular has been widely praised by medical community for its ability to reduce both examination time and patient stress.
- *5 Mydriatic and non-mydriatic examination
Eye examination using a retinal camera can be carried out either mydriatically, where pupil is dilated using eye drops, or non-mydriatically, where pupil is not dilated. In general, mydriatic exams can provide more detailed information, yet patients may experience intolerance to bright light. A physician decides which exam type to use.
- *6 Retinal camera
Used to examine the condition of, and check for bleeding in, the retina and blood vessels at the back of the eye. Plays an important role in the early diagnosis of a variety of eye conditions as well as diabetes.
Fully Automatic Noncontact Tonometer
Fully Automated Precision Measurement of Intraocular Pressure
The measurement of intraocular pressure,*7 essential in ophthalmic treatment, is performed by measuring pressure at the cornea. The procedure is carried out using a non-contact tonometer, which places an air puff nozzle built into the center of an objective lens very close to the surface of the patient's eye. A puff of air is blown at the center of the cornea and measurements are taken. With conventional manual systems, tracking the movements of the patient's eye to determine correct alignment proved difficult and relied on the experience of the operator.
To enable the full automation of the intraocular pressure measurement procedure, Canon developed the following technologies:
- Rough auto-alignment drive technology that quickly and safely identifies the patient's eye within a wide field of view
- Fine auto-alignment drive technology that quickly and precisely identifies the correct position of the apex of the cornea even with eye movement
- Safe drive-control technology that avoids the hazards of positioning the air puff nozzle too close to the patient's eye
- 3D-drive technology to ensure the smooth transport of the measurement unit (objective lens)
Featuring these technologies, Canon's fully automated non-contact tonometer TX-20P enables safe, precise tonometry with extremely simple operation. It is being adopted not only by ophthalmic clinics, but also for use with regular physical checkups and screening for adult-onset diseases.
- *7 Intraocular pressure
The pressure of intraocular fluid inside the eyeball. Abnormal intraocular pressure, which leads to glaucoma and other disorders, is one of the leading causes of vision loss.