FEATURE: MEDICAL AV
of separate devices together in the way the physician wants to access them.”
BREAKING BOUNDARIES Integrating disparate systems is not as straightforward as would be expected in, say, the corporate AV world, however. Holdoway warns: “Any changes made to a medical system must not impinge on that system: you cannot simply split a video output to an additional screen in a viewing area or control room without considering the reliability and integrity of the original image. “Manufacturers like to
keep a boundary around their systems and to break into that boundary is difficult; it can be done but requires the trust and confidence of the original equipment installer. There are different signal formats in use across the manufacturers’ products which must be considered. Any device inserted into a signal chain that affects the quality of the original image in any way; by altering its colour or greyscale rendition or geometry, nullifies DICOM compliance and must not be done.”
In addition the medical
environment itself presents problems: infection control requires that equipment can be treated with specific disinfectants; installing cabling and ventilated equipment in pressure
controlled treatment rooms and operating theatres is often prohibited. The presence of fluids and gases and the need to meet specific safety standards demands that only equipment designed for medical use is used. Control rooms associated with operating theatres are not subject to quite the strict levels of cleanliness but do still have their own higher- than-normal stipulations. For integrators in this field, it can often be a lengthy process to enter the sector and become recognised. Hospitals do not tend to operate their own specialist AV staff; rather an ‘interested’ doctor or consultant will become involved in the technology and will be a key player in the decision-making process, always looking at it from their perspective.
“Gaining the trust and confidence of hospital staff is a long-term process of relationship building and understanding clinicians’ needs and methodologies,” explains Steve Wood, managing director of Parity Medical. “Each installation is unique; not just in terms of the application meeting the particular specialisation of the clinical team, but the fact that many hospitals are housed in very old buildings with their own architectural peculiarities. Every organisation has
their own working practices and there is very little commonality between them. Our experience within the medical sector, and the brand and solution portfolio we have developed over the years, means that we can help a department establish their requirements in their specific setting and suggest and adapt solutions for their consideration based on other, previous installations.”
ROOM FOR OPPORTUNITY In medical establishments, multidisciplinary team (MDT) rooms provide opportunities for professional AV system integrators at a slightly lower level of complexity. These are areas in which specialists from different clinical areas meet to discuss and review cases and are often extended to fulfil additional roles within a hospital: seminar rooms, videoconferencing suites, live procedure and presentation and lecture theatres. They are outside the strict infection-controlled and diagnostic areas of the establishment and do not require medical-grade, fully DICOM-compliant presentation technology. University hospital training environments also offer additional possibilities for audiovisual integration of medical-class technology. The equipment required in
MDT rooms and training, and the way it is operated, closely resembles that of corporate
[MEDICAL QAWEB]
MediCal QAWeb is a Cloud- based service that automates quality assurance of Barco’s medical displays by constantly monitoring devices to continuously check compliance with a wide range of regional QA guidelines. Asset management tools provide an overview of all compatible displays within an establishment ensuring that their self-calibration process is functioning and will
boardrooms and conference rooms. They do however demand that the highest quality equipment is used: the diagnosis of a medical condition may have already been made but doctors, consultants and nursing staff still need the best possible images on which to review and plan future care. Projectors and flatpanel
displays will usually be specified with DICOM simulation mode. These devices are, as Peter Adams, sales manager medical solutions, NEC explains, “factory calibrated prior to delivery to meet DICOM section 14 based on the measured characteristics of a sample display from a batch; for native gamma curve, brightness, luminance and so on and the corresponding LUT (look-up table) applied to the whole batch – usually of 50 or fewer units. This means that the display performs almost as well as a DICOM-compliant unit. It provides a lower- cost alternative that is demonstrably sufficient for clinical review applications without needing the ability to be individually set and calibrated.” DICOM simulation
The Dome S6c LED widescreen 6MP radiology display from NDS Surgical Imaging
www.installation-international.com
displays are not classified as medical devices and should not be used for the medical diagnostic applications of fully DICOM- compliant displays. However the two types share common characteristics that raise
provide a warning notification whenever a display falls outside designated calibration settings or is physically removed. QAWeb ensures the continuous calibration of displays in clinical diagnostic applications while reducing the management and administrative overhead normally associated with essential periodic DICO section 14 calibration.
them above the level of professional displays. “To achieve the same level of grey shades as a plain X-ray film a diagnostic monitor would need to have at least 450 candela brightness, any less and the image will be clipped and some detail could be missed,” says Rob Musson of Eizo.
“The IPEM (Institute of
Physicists and Engineering in Medicine) guidelines include tolerance levels and how often a display should be checked, which matches what the UK Medical Physicists would consider right for UK users. AAPM (American Association of Physics in Medicine) guidelines, TG18, set forth visual, quantitative and advanced testing methodologies for both classes of display, including recommendations for ambient lighting which can have a dramatic effect on the visual image presented on a screen. They also offer test cards that assist in establishing whether displays are fully calibrated for medical diagnosis, covering all aspects of a display’s performance: luminance, resolution, noise, glare and even example anatomical images.” Integration with
PACs systems is also a fundamental requirement in MDT rooms. This is an area that is unlikely to be familiar to general AV integrators, but is certainly not beyond their technical ability. Signal processing, switching
July 2014 29
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60