DICOMweb is a term applied to the family of RESTful DICOM services defined for sending, retrieving and querying for medical images and related information.
113-589: The intent is to provide a light-weight mobile device and web browser friendly mechanism for accessing images, which can be implemented by developers who have minimal familiarity with the DICOM standard and which uses consumer application friendly mechanisms like http , JSON and media types (like "image/jpeg") to the maximum extent possible. The standard is formally defined in DICOM PS3.18 Web Services. The DICOMweb services are distinguished from other DICOM web services by
226-488: A computer which controls the scanner and stores scans. Small portable scanners, either sheetfed or handheld and operated by batteries and with storage capability, are available for use away from a computer; stored scans can be transferred later. Many can scan both small documents such as business cards and till receipts , as well as letter-sized documents. The higher-resolution cameras fitted to some smartphones can produce reasonable quality document scans by taking
339-445: A copper plate with a raised image. When the stylus makes contact with a raised part of the plate, it sends a pulse across a pair of wires to a receiver containing an electrode linked to another pendulum. A piece of paper impregnated with an electrochemically sensitive solution resides underneath the electrode and changes color whenever a pulse reaches the electrode. A gear advances the copper plate and paper in tandem with each swing of
452-489: A digital image . The most common type of scanner used in offices and in the home is the flatbed scanner , where the document is placed on a glass window for scanning. A sheetfed scanner , which moves the page across an image sensor using a series of rollers, may be used to scan one document at a time or multiple, as in an automatic document feeder . A handheld scanner is a portable version of an image scanner that can be used on any flat surface. Scans are usually downloaded to
565-442: A laser beam to scan pages up to 11 by 14 inches at a maximum resolution of 1000 lines per inch. Although it was only capable of scanning in 1-bit monochrome, the on-board processor was capable of halftoning, unsharp masking , contrast adjustment, and anamorphic distortions , among other features. The Autokon 8400 could either be connected to a film recorder to create a negative for producing plates or connected to
678-530: A CD). The Service Class User (SCU: similar to a client ), a modality or workstation, etc., uses the confirmation from the Service Class Provider (SCP: similar to a server ), an archive station for instance, to make sure that it is safe to delete the images locally. This enables a workstation to find lists of images or other such objects and then retrieve them from a picture archiving and communication system. The DICOM modality worklist service provides
791-557: A CT scanner, queries a service provider, such as a RIS , to get this information which is then presented to the system operator and is used by the imaging device to populate details in the image metadata. Prior to the use of the DICOM modality worklist service, the scanner operator was required to manually enter all the relevant details. Manual entry is slower and introduces the risk of misspelled patient names, and other data entry errors. A complementary service to modality worklist, this enables
904-429: A Dmax close to 4.0d with proper exposure, and so can black-and-white negative film. Consumer-level flatbed photo scanners have a dynamic range in the 2.0–3.0 range, which can be inadequate for scanning all types of photographic film , as Dmax can be and often is between 3.0d and 4.0d with traditional black-and-white film. Color film compresses its 12 stops of a possible 16 stops (film latitude) into just 2.0d of space via
1017-444: A color negative. In this system, three color-separated plates (of CMY values) are prepared from a color negative via dot etching and placed in the scanner bed. Above each plate are rigidly fixed, equidistant light beam projectors that focus a beam of light onto one corner of the plate. The entire bed with all three plates moves horizontally, back and forth, to reach the opposite corners of the plate; with each horiztonal oscillation of
1130-407: A dedicated 2 pair cable ( EIA-485 ). The first demonstration of ACR/NEMA V2.0 interconnectivity technology was held at Georgetown University, May 21–23, 1990. Six companies participated in this event, DeJarnette Research Systems, General Electric Medical Systems, Merge Technologies, Siemens Medical Systems, Vortech (acquired by Kodak that same year) and 3M. Commercial equipment supporting ACR/NEMA 2.0
1243-411: A dedicated Working Group within DICOM, and DICOM is applicable to any field of medicine in which imaging is prevalent, including:, radiology, cardiology, oncology, nuclear medicine, radiotherapy, neurology, orthopedics, obstetrics, gynecology, ophthalmology, dentistry, maxillofacial surgery, dermatology, pathology, clinical trials, veterinary medicine, and medical/clinical photography DICOM have reserved
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#17328587404791356-419: A document in order to judge what area of the document should be scanned (if not the entirety of it), before scanning it at a higher resolution. Some flatbed scanners incorporate sheet-feeding mechanisms called automatic document feeders (ADFs) that use the same scanning element as the flatbed portion. This type of scanner is sometimes called a reflective scanner , because it works by shining white light onto
1469-470: A few key attributes and details of the application that wrote it) is added. To promote identical grayscale image display on different monitors and consistent hard-copy images from various printers, the DICOM committee developed a lookup table to display digitally assigned pixel values. To use the DICOM grayscale standard display function (GSDF) , images must be viewed (or printed) on devices that have this lookup curve or on devices that have been calibrated to
1582-425: A file of a chest x-ray image may contain the patient ID within the file, so that the image can never be separated from this information by mistake. This is similar to the way that image formats such as JPEG can also have embedded tags to identify and otherwise describe the image. A DICOM data object consists of a number of attributes, including items such as name, ID, etc., and also one special attribute containing
1695-497: A joint Working Group to harmonize areas where the two standards overlap and address imaging integration in the electronic medical record. Integrating the Healthcare Enterprise (IHE) is an industry sponsored non-profit organization that profiles the use of standards to address specific healthcare use cases. DICOM is incorporated in a variety of imaging related IHE profiles. Systematized Nomenclature of Medicine (SNOMED)
1808-669: A laser onto the page for calibration and software skew correction. A film scanner , also known as a slide scanner or a transparency scanner, is a type of specialized flatbed scanner specifically for scanning film negatives and slides . A typical film scanner works by passing a narrowly focused beam of light through the film and reading the intensity and color of the light that emerges. The lowest-cost dedicated film scanners can be had for less than $ 50, and they might be sufficient for modest needs. From there they inch up in staggered levels of quality and advanced features upward of five figures. Image scanners are usually used in conjunction with
1921-506: A light projector hovering over a fourth, unexposed lithographic plate. This plate receives a color-corrected, continuous-tone dot-etch of either the cyan, magenta, or yellow values. The fourth plate is replaced with another unexposed plate, and the process repeats until three color-corrected plates, of cyan, magenta and yellow, are produced. In the 1950s, the Radio Corporation of America (RCA) took Hardy and Wurzburg's patent and replaced
2034-466: A list of imaging procedures that have been scheduled for performance by an image acquisition device (sometimes referred to as a modality system). The items in the worklist include relevant details about the subject of the procedure (patient ID, name, sex, and age), the type of procedure (equipment type, procedure description, procedure code) and the procedure order (referring physician, accession number , reason for exam). An image acquisition device, such as
2147-411: A long, motor-driven rotating cylinder, with five equidistant contacts scanning over each plate at the same starting position. The Bartlane system was initially used exclusively by telegraph, with the five-bit Baudot code used to transmit the grayscale digital image. In 1921, the system was modified for offline use, with a five-bit paper tape punch punching holes depending on whether its connections to
2260-732: A mainframe or minicomputer for further image processing and digital storage. The Autokon 8400 enjoyed widespread use in newspapers—ECRM shipped 1,000 units to newspaper publishers by 1985 —but its limited resolution and maximum scan size made it unsuitable for commercial printing. In 1982, ECRM introduced the Autokon 8500, capable of scanning up to 1200 lines per inch. Four of ECRM's competitors introduced commercial flatbed scanners that year, including Scitex , Agfa-Gevaert , and Linotype-Hell , all of which were capable of scanning larger prints at higher resolutions. In 1977, Raymond Kurzweil , of his start-up company Kurzweil Computer Products, released
2373-423: A mainstream commodity". A flatbed scanner is a type of scanner that provides a glass bed ( platen ) on which the object to be scanned lies motionless. The scanning element moves vertically from under the glass, scanning either the entirety of the platen or a predetermined portion. The driver software for most flatbed scanners allows users to prescan their documents—in essence, to take a quick, low-resolution pass at
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#17328587404792486-431: A network. The file format for offline media is a later addition to the standard. The DICOM Store service is used to send images or other persistent objects (structured reports, etc.) to a picture archiving and communication system (PACS) or workstation. The DICOM storage commitment service is used to confirm that an image has been permanently stored by a device (either on redundant disks or on backup media, e.g. burnt to
2599-405: A normal letter and much longer, remain available as of 2024 . Some computer mice can also scan documents. A drum scanner is a type of scanner that uses a clear, motor-driven rotating cylinder (drum) onto which a print, a film negative, a transparency, or any other flat object is taped or otherwise secured. A beam of light either projects past, or reflects off, the material to be scanned onto
2712-412: A photograph with the phone's camera and post-processing it with a scanning app, a range of which are available for most phone operating systems , to whiten the background of a page, correct perspective distortion so that the shape of a rectangular document is corrected, convert to black-and-white, etc. Many such apps can scan multiple-page documents with successive camera exposures and output them either as
2825-407: A retired feature that is no longer documented in the current standard. While the DICOM standard has achieved a near universal level of acceptance among medical imaging equipment vendors and healthcare IT organizations, the standard has its limitations. DICOM is a standard directed at addressing technical interoperability issues in medical imaging. It is not a framework or architecture for achieving
2938-502: A scan of a letter-sized print at 200-dpi; its grayscale counterpart, the DS-200, took only 30 seconds to make a scan at the same size and resolution. The first relatively affordable flatbed scanner for personal computers appeared in February 1987 with Hewlett-Packard 's ScanJet , which was capable of scanning 4-bit (64-shade) grayscale images at a maximum resolution of 300 dpi. By
3051-513: A scanner is its resolution , measured in pixels per inch (ppi), sometimes more accurately referred to as samples per inch (spi). Instead of using the scanner's true optical resolution, the only meaningful parameter, manufacturers like to refer to the interpolated resolution, which is much higher thanks to software interpolation . As of 2009 , a high-end flatbed scanner can scan up to 5400 ppi and drum scanners have an optical resolution of between 3000 and 24000 ppi. Effective resolution refers to
3164-403: A scanner with at least a 3.6d dynamic range, but also a Dmax between 4.0d to 5.0d. High-end (photo lab) flatbed scanners can reach a dynamic range of 3.7, and Dmax around 4.0d. Dedicated film scanners have a dynamic range between 3.0d–4.0d. Office document scanners can have a dynamic range of less than 2.0d. Drum scanners have a dynamic range of 3.6–4.5. For scanning film, infrared cleaning
3277-418: A series of mirrors, which focus the beam onto the drum scanner's photomultiplier tube (PMT). After one revolution, the beam of light moves down a single step. When scanning transparent media, such as negatives, a light beam is directed from within the cylinder onto the media; when scanning opaque items, a light beam from above is reflected off the surface of the media. When only one PMT is present, three passes of
3390-612: A single apparatus that can be made available to all members of a workgroup. Battery-powered portable scanners store scans on internal memory; they can later be transferred to a computer either by direct connection, typically USB, or in some cases a memory card may be removed from the scanner and plugged into the computer. A raster image editor must be able to communicate with a scanner. There are many different scanners, and many of those scanners use different protocols. In order to simplify applications programming, some application programming interfaces (APIs) were developed. The API presents
3503-444: A single file or multiple-page files. Some smartphone scanning apps can save documents directly to online storage locations, such as Dropbox and Evernote , send via email, or fax documents via email-to-fax gateways. Smartphone scanner apps can be broadly divided into three categories: Scanners equipped with charge-coupled device (CCD) scanning elements require a sophisticated series of mirrors and lenses to reproduce an image, but
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3616-449: A single frame of the output as an image file. Document cameras may even use the same APIs as scanners when connected to computers. A planetary scanner is a type of very-high-resolution document camera used for capturing certain fragile documents. A book scanner is another kind of document camera, pairing a digital camera with a scanning area defined by a mat to assist in scanning books. Some more advanced models of book scanners project
3729-401: A standard committee in 1983. Their first standard, ACR/NEMA 300, entitled "Digital Imaging and Communications", was released in 1985. Very soon after its release, it became clear that improvements were needed. The text was vague and had internal contradictions. In 1988 the second version was released. This version gained more acceptance among vendors. The image transmission was specified as over
3842-567: A team led by Russell A. Kirsch . It used a photomultiplier tube to detect light at a given point and produced an amplified signal that a computer could read and store into memory. The computer of choice at the time was the SEAC mainframe ; the maximum horizontal resolution that the SEAC was capable of processing was 176 pixels. The first image ever scanned on this machine was a photograph of Kirsch's three-month-old son, Walden. In 1969, Dacom introduced
3955-470: A time past a stationary scanning element (two scanning elements, in the case of scanners with duplex functionality). Unlike flatbed scanners, sheetfed scanners are not equipped to scan bound material such as books or magazines, nor are they suitable for any material thicker than plain printer paper. Some sheetfed scanners, called automatic document feeders (ADFs), are capable of scanning several sheets in one session, although others only accept one page at
4068-451: A time. Some sheetfed scanners are portable , powered by batteries, and have their own storage, eventually transferring stored scans to a computer. A handheld scanner is a type of scanner that must be manually dragged or gilded by hand across the surface of the object to be scanned. Scanning documents in this manner requires a steady hand, as an uneven scanning rate produces distorted images. Some handheld scanners have an indicator light on
4181-443: A useful clinical workflow. The Integrating the Healthcare Enterprise (IHE) initiative layered on top of DICOM (and HL-7 ) defines profiles to select features from these standards to implement transactions for specific medical imaging interoperability use cases. Though always Internet compatible and based on transport over TCP , over time there has been an increasing need to support port 80 HTTP transport to make use easier within
4294-834: Is a technical standard for the digital storage and transmission of medical images and related information. It includes a file format definition, which specifies the structure of a DICOM file , as well as a network communication protocol that uses TCP/IP to communicate between systems. The primary purpose of the standard is to facilitate communication between the software and hardware entities involved in medical imaging , especially those that are created by different manufacturers. Entities that utilize DICOM files include components of picture archiving and communication systems (PACS) , such as imaging machines (modalities) , radiological information systems (RIS) , scanners , printers , computing servers , and networking hardware . The DICOM standard has been widely adopted by hospitals and
4407-563: Is a multi-dimensional multi-frame image. In these cases, three- or four-dimensional data can be encapsulated in a single DICOM object. Pixel data can be compressed using a variety of standards, including JPEG , lossless JPEG , JPEG 2000 , and run-length encoding (RLE) . LZW (zip) compression can be used for the whole data set (not just the pixel data), but this has rarely been implemented. DICOM uses three different data element encoding schemes. With explicit value representation (VR) data elements, for VRs that are not OB, OW, OF, SQ, UT, or UN ,
4520-471: Is a standard developed by American College of Radiology (ACR) and National Electrical Manufacturers Association (NEMA). In the beginning of the 1980s, it was very difficult for anyone other than manufacturers of computed tomography or magnetic resonance imaging devices to decode the images that the machines generated. Radiologists and medical physicists wanted to use the images for dose-planning for radiation therapy . ACR and NEMA collaborated and formed
4633-459: Is a systematic, computer-processable collection of medical terms, in human and veterinary medicine, to provide codes, terms, synonyms and definitions which cover anatomy, diseases, findings, procedures, microorganisms, substances, etc. DICOM data makes use of SNOMED to encode relevant concepts. XnView supports .dic / .dicom for MIME type application/dicom The best known standards and protocols used by DICOM are: The DICOM standard
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4746-412: Is a technique used to remove the effects of dust and scratches on images scanned from film; many modern scanners incorporate this feature. It works by scanning the film with infrared light; the dyes in typical color film emulsions are transparent to infrared light, but dust and scratches are not, and block infrared; scanner software can use the visible and infrared information to detect scratches and process
4859-545: Is a type of scanner that places the scanning element in a housing on top of a vertical post, hovering above the document or object to be scanned, which lies stationary on an open-air bed. Chinon Industries patented a specific type of overhead scanner, which uses a rotating mirror to reflect the contents of the bed onto a linear CCD, in 1987. Although very flexible—allowing users to scan not only two-dimensional prints and documents but any 3D object, of any size—the Chinon design required
4972-619: Is also implemented by devices associated with images or imaging workflow including, PACS (picture archiving and communication systems), image viewers and display stations, CAD (computer-aided detection/diagnosis systems), 3D visualization systems, clinical analysis applications, image printers, Film scanners, media burners (that export DICOM files onto CDs, DVDs, etc.), media importers (that import DICOM files from CDs, DVDs, USBs, etc.), RIS (radiology information systems), VNA (vendor-neutral archives), EMR (electronic medical record) systems, and radiology reporting systems Many fields of medicine have
5085-400: Is no longer used. There are no "minor" versions to the standard (e.g., no such thing as "DICOM 3.1") and there are no current plans to develop a new, incompatible, version of the standard (i.e., no "DICOM 4.0"). The standard should be referenced without specification of the date of release of a particular published edition, except when specific conformance requirements are invoked that depend on
5198-932: Is org.nema.dicom. There is also an ongoing media exchange test and "connectathon" process for CD media and network operation that is organized by the IHE organization. The core application of the DICOM standard is to capture, store and distribute medical images. The standard also provides services related to imaging such as managing imaging procedure worklists, printing images on film or digital media like DVDs, reporting procedure status like completion of an imaging acquisition, confirming successful archiving of images, encrypting datasets, removing patient identifying information from datasets, organizing layouts of images for review, saving image manipulations and annotations, calibrating image displays, encoding ECGs, encoding CAD results, encoding structured measurement data, and storing acquisition protocols. The DICOM information object definitions encode
5311-430: Is that the file format admits executable code and may contain malware . DVTk is an Open Source project for testing, validating and diagnosing communication protocols and scenarios in medical environments. It supports DICOM, HL7 and IHE integration profiles. Health Level 7 is a non-profit organization involved in the development of international healthcare informatics interoperability standards. HL7 and DICOM manage
5424-488: Is the space taken up in the 0 to 5 scale, and Dmin and Dmax denote where the least dense and most dense measurements on a negative or positive film. The density range of negative film is up to 3.6d, while slide film dynamic range is 2.4d. Color negative density range after processing is 2.0d thanks to the compression of the 12 stops into a small density range. Dmax will be the densest on slide film for shadows, and densest on negative film for highlights. Some slide films can have
5537-512: Is used in a wide variety of resources (IHE, HL7 ... a) that are related to images. The ISO12052: 2017 and CEN 12052 standards refer to the DICOM standard. In December 2023, cybersecurity researcher Sina Yazdanmehr unveiled a critical security issue within the Store service. This revelation, presented at Black Hat Briefings , demonstrated the potential for malicious actors to manipulate existing series of medical images. Yazdanmehr's research highlighted
5650-647: Is used to send images to a DICOM printer, normally to print an "X-Ray" film. There is a standard calibration (defined in DICOM Part 14) to help ensure consistency between various display devices, including hard copy printout. The format for offline media files is specified in Part 10 of the DICOM Standard. Such files are sometimes referred to as "Part 10 files". DICOM restricts the filenames on DICOM media to 8 characters (some systems wrongly use 8.3, but this does not conform to
5763-494: Is used worldwide to store, exchange, and transmit medical images . DICOM has been central to the development of modern radiological imaging : DICOM incorporates standards for imaging modalities such as radiography, ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and radiation therapy. DICOM includes protocols for image exchange (e.g., via portable media such as DVDs), image compression, 3-D visualization, image presentation, and results reporting. DICOM
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#17328587404795876-419: The computer that the scanner is connected to, although some scanners are able to store scans on standalone flash media (e.g., memory cards and USB drives ). Modern scanners typically use a charge-coupled device (CCD) or a contact image sensor (CIS) as the image sensor, whereas drum scanners , developed earlier and still used for the highest possible image quality, use a photomultiplier tube (PMT) as
5989-594: The medical software industry, and is sometimes used in smaller-scale applications, such as dentists' and doctors' offices. The National Electrical Manufacturers Association (NEMA) holds the copyright to the published standard, which was developed by the DICOM Standards Committee (which includes some NEMA members. It is also known as NEMA standard PS3, and as ISO standard 12052:2017: "Health informatics – Digital imaging and communication in medicine (DICOM) including workflow and data management" . DICOM
6102-434: The 111 fax machine, which was the first digital fax machine to employ data compression using an on-board computer. It employed a flatbed design with a continuous feed capable of scanning up to letter paper in 1-bit monochrome (black and white). The first flatbed scanner used for digital image processing was the Autokon 8400, introduced by ECRM Inc., a subsidiary of AM International , in 1975. The Autokon 8400 used
6215-455: The DICOM files on the media. The DICOMDIR information provides substantially greater information about each file than any filename could, so there is less need for meaningful file names. DICOM files typically have a .dcm file extension if they are not part of a DICOM media (which requires them to be without extension). The MIME type for DICOM files is defined by RFC 3240 as application/dicom. The Uniform Type Identifier type for DICOM files
6328-599: The DICOMweb Cheatsheet. Roughly speaking, the DICOMweb services can be compared with the conventional DIMSE DICOM services as follows: Indeed, apart from the different encoding of the request, packaging of the response and protocol used, the services are sufficiently similar that a DICOMweb proxy to a conventional implementation of DICOM DIMSE services can be implemented (this is by design). The conventional DIMSE DICOM services do actually have capabilities that correspond to
6441-465: The GSDF curve. In addition to a value representation, each attribute also has a value multiplicity to indicate the number of data elements contained in the attribute. For character string value representations, if more than one data element is being encoded, the successive data elements are separated by the backslash character "\". DICOM consists of services, most of which involve transmission of data over
6554-492: The German engineer Arthur Korn introduced the phototelautograph, a fax machine that used a light-sensitive selenium cell to scan a paper to be copied, instead of relying on a metallic drum and stylus. It was even more commercially successful than Gray's machine and became the basis for telephotography machines used by newspapers around the world from the early 1900s onward. Alexander Murray and Richard Morse invented and patented
6667-676: The Health Insurance Portability and Accountability Act ( HIPAA ) in the United States and the General Data Protection Regulation ( GDPR ) in Europe is essential for protecting patient privacy and ensuring the integrity of medical records. Image scanner An image scanner (often abbreviated to just scanner ) is a device that optically scans images, printed text, handwriting , or an object and converts it to
6780-621: The IS-22, a cartridge that fit into their inkjet printers to convert them into sheetfed scanners. In early 1985, the first flatbed scanner for the IBM PC , the Datacopy Model 700, was released. Based on a CCD imaging element, the Model 700 was capable of scanning letter-sized documents at a maximum resolution of 200 dpi at 1-bit monochrome. The Model 700 came with a special interface card for connecting to
6893-553: The Kurzweil Reading Machine, which was the first flatbed scanner with a charge-coupled device (CCD) imaging element. The Kurzweil Reading Machine was invented to assist blind people in reading books that had not been translated to braille . It comprised the image scanner and a Data General Nova minicomputer —the latter performing the image processing, optical character recognition (OCR), and speech synthesis . The first scanners for personal computers appeared in
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#17328587404797006-550: The Macintosh simultaneously. The ImageWriter's carriage, controlled by the ThunderScan, moves left-to-right to scan one 200- dpi (dots per inch) line at a time, with the carriage return serving to advance the scanner down the print to be scanned. The ThunderScan was the Macintosh's first scanner and sold well but operated very slowly and was only capable of scanning prints at 1-bit monochrome. In 1999, Canon iterated on this idea with
7119-668: The PC, and an optional, aftermarket OCR software card and software package were sold for the Model 700. In April 1985, LaserFAX Inc. introduced the first CCD-based color flatbed scanner, the SpectraSCAN 200, for the IBM PC. The SpectraSCAN 200 worked by placing color filters over the CCD and taking four passes (three for each primary color and one for black) per scan to build up a color reproduction. The SpectraSCAN 200 took between two and three minutes to produce
7232-629: The RGB signals into color-corrected cyan, magenta, yellow, and black (CMYK) values. The processed signals are then sent to four lathes that etch CMYK halftone dots onto the offset cylinders. In 1948, Arthur Hardy of the Interchemical Corporation and F. L. Wurzburg of the Massachusetts Institute of Technology invented the first analog, color flatbed image scanner, intended for producing color-corrected lithographic plates from
7345-468: The alarming capability of attackers to destroy a series of images or introduce misleading indicators of illness. Ensuring the security of patient data within DICOM is critical, as these files often contain sensitive personal health information (PHI). Security measures for DICOM data include encryption, access control, and auditing mechanisms to prevent unauthorized access, modification, or disclosure of patient information. Compliance with regulations such as
7458-468: The array. This data is then processed with some proprietary algorithm to correct for different exposure conditions, and sent to the computer via the device's input/output interface (usually USB, previous to which was SCSI or bidirectional parallel port in older units). Color depth varies depending on the scanning array characteristics, but is usually at least 24 bits. High-quality models have 36-48 bits of color depth. Another qualifying parameter for
7571-407: The bed, the bed moves down one step to cover the entire vertical area of the plate. While this is happening, the beam of light focused on a given spot on the plate gets reflected and bounced off to a photocell adjacent to the projector. Each photocell connects to an analog image processor , which evaluates the reflectance of the combined CMY values using Neugebauer equations and outputs a signal to
7684-564: The beginning of 1988, the ScanJet had accounted for 27 percent of all scanner sales in terms of dollar volume, per Gartner Dataquest . In February 1989, the company introduced the ScanJet Plus, which increased the bit depth to 8 bits (256 shades) while costing only US$ 200 more than the original ScanJet's $ 1990 (equivalent to $ 4,891 in 2023). This led to a massive price drop in grayscale scanners with equivalent or lesser features in
7797-523: The best possible quality is required lossless compression should be used; reduced-quality files of smaller size can be produced from such an image when required (e.g., image designed to be printed on a full page, and a much smaller file to be displayed as part of a fast-loading web page). Purity can be diminished by scanner noise, optical flare, poor analog to digital conversion, scratches, dust, Newton's rings , out-of-focus sensors, improper scanner operation, and poor software. Drum scanners are said to produce
7910-533: The complex optics of CCDs scanners. However, their depth of field is much worse, resulting in blurry scans if the scanned document is not perfectly flush against the platten. Because the sensors require far less power than CCD scanners, CIS scanners are able to be manufactured down to a low cost and are typically much lighter in weight and depth than CCD scanners. Scanners equipped with photomultiplier tubes (PMT) are nearly exclusively drum scanners . Color scanners typically read RGB (red-green-blue) color data from
8023-460: The contacts are bridged or not. The result was a stored digital image with five gray levels. Reproduction of the image was achieved with a lamp passing over the punched holes, exposing five different intensities of light onto a film negative. The first scanner to store its images digitally onto a computer was a drum scanner built in 1957 at the National Bureau of Standards (NBS, later NIST) by
8136-414: The data produced by a wide variety of imaging device types, including, CT (computed tomography), MRI (magnetic resonance imaging), ultrasound , X-ray , fluoroscopy , angiography , mammography , breast tomosynthesis, PET ( positron emission tomography ), SPECT (single-photon emission computed tomography), Endoscopy, microscopy, nd whole slide imaging, OCT (optical coherence tomography). DICOM
8249-426: The drum was connected to three lathes that etched cyan, magenta, and yellow (CMY) halftone dots onto three offset cylinders directly. The rights to the patent were sold to Printing Developments Incorporated (P.D.I.) in 1946, who improved on the design by using a photomultiplier tube to image the points on the negative, which produced an amplified signal that was then fed to a single-purpose computer that processed
8362-440: The early 1990s professional flatbed scanners were available over a local computer network . This proved useful to publishers, print shops, etc. This functionality largely fell out of use as the cost of flatbed scanners reduced enough to make sharing unnecessary. From 2000 all-in-one multi-purpose devices became available which were suitable for both small offices and consumers, with printing, scanning, copying, and fax capability in
8475-455: The first analog color scanner at Eastman Kodak in 1937. Intended for color separation at printing presses , their machine was an analog drum scanner that imaged a color transparency mounted in the drum, with a light source placed underneath the film, and three photocells with red, green, and blue color filters reading each spot on the transparency to translate the image into three electronic signals. In Murray and Morse's initial design,
8588-447: The foil and a stylus that scans across the drum and sends a pulse down a pair of wires when it contacts a conductive point on the foil. The receiver contains an electrode that touches a sheet of chemically treated paper, which changes color when the electrode receives a pulse; the result is a reverse contrast (white-on-blue) reproduction of the original image. Bakewell's fax machine was marginally more successful than Bain's but suffered from
8701-697: The following TCP and UDP port numbers by the Internet Assigned Numbers Authority (IANA): 104 well-known port for DICOM over Transmission Control Protocol (TCP) or User Datagram Protocol (UDP). Since 104 is in the reserved subset, many operating systems require special privileges to use it; 2761 registered port for DICOM using Integrated Secure Communication Layer (ISCL) over TCP or UDP; 2762 registered port for DICOM using Transport Layer Security (TLS) over TCP or UDP; 11112 registered port for DICOM using standard, open communication over TCP or UDP. The standard recommends but does not require
8814-405: The format for each data element is: GROUP (2 bytes) ELEMENT (2 bytes) VR (2 bytes) LengthInByte (2 bytes) Data (variable length). For the other explicit data elements or implicit data elements, see section 7.1 of Part 5 of the DICOM Standard. The same basic format is used for all applications, including network and file usage, but when written to a file, usually a true "header" (containing copies of
8927-672: The image are required for a full-color RGB scan. When three PMTs are present, only a single pass is required. The photomultiplier tubes of drum scanners offer superior dynamic range to that of CCD sensors. For this reason, drum scanners can extract more detail from very dark shadow areas of a transparency than flatbed scanners using CCD sensors. The smaller dynamic range of the CCD sensors (versus photomultiplier tubes) can lead to loss of shadow detail, especially when scanning very dense transparency film. Drum scanners are also able to resolve true detail in excess of 10000 dpi, producing higher-resolution scans than any CCD scanner. An overhead scanner
9040-444: The image pixel data (i.e. logically, the main object has no "header" as such, being merely a list of attributes, including the pixel data). A single DICOM object can have only one attribute containing pixel data. For many modalities, this corresponds to a single image. However, the attribute may contain multiple "frames", allowing storage of cine loops or other multi-frame data. Another example is NM data, where an NM image, by definition,
9153-468: The image sensor. Document cameras , which use commodity or specialized high-resolution cameras, photograph documents all at once. Image scanners are considered the successors of early facsimile (fax) machines. The earliest attempt at a fax machine was patented in 1843 by the Scottish clockmaker Alexander Bain but never put into production. In his design, a metal stylus linked to a pendulum scans across
9266-781: The image to greatly reduce their visibility, considering their position, size, shape, and surroundings. Scanner manufacturers usually have their own names attached to this technique. For example, Epson , Minolta , Nikon , Konica Minolta , Microtek , and others use Digital ICE , while Canon uses its own system, FARE (Film Automatic Retouching and Enhancement). Plustek uses LaserSoft Imaging iSRD . Some independent software developers design infrared cleaning tools. By combining full-color imagery with 3D models, modern hand-held scanners are able to completely reproduce objects electronically. The addition of 3D color printers enables accurate miniaturization of these objects, with applications across many industries and professions. For scanner apps,
9379-505: The image; later ones scan in monochrome or color, as desired. A hand scanner may also have a small window through which the document being scanned could be viewed. As hand scanners are much narrower than most normal document or book sizes, software (or the end user) needed to combine several narrow "strips" of scanned documents to produce the finished article. Inexpensive, portable , battery-powered or USB-powered wand scanners and pen scanners, typically capable of scanning an area as wide as
9492-496: The instance and frame level (Instance and Frame Level Retrieve) and separate meta data retrieval capabilities (Composite Instance Retrieve Without Bulk Data) of DICOMweb, though these are not nearly as widely implemented as the traditional study-root study, series and image retrieval services. Earlier DICOM web services used either URL parameters (WADO-URI) or SOAP-based web services (WADO-WS) to retrieve DICOM objects. The original Web Access to DICOM Persistent Objects (WADO) standard
9605-442: The level of captured detail. The size of the file created increases with the square of the resolution; doubling the resolution quadruples the file size . A resolution must be chosen that is within the capabilities of the equipment, preserves sufficient detail, and does not produce a file of excessive size. The file size can be reduced for a given resolution by using "lossy" compression methods such as JPEG, at some cost in quality. If
9718-401: The market. The number of third-party developers producing software and hardware supporting these scanners jumped dramatically in turn, effectively popularizing the scanner for the personal computer user. By 1999, the cost of the average color-capable scanner had dropped to $ 300 (equivalent to $ 549 in 2023). That year, Computer Shopper declared 1999 "the year that scanners finally became
9831-521: The maxima and minima of each oscillation. In 1893, the American engineer Elisha Gray introduced the telautograph , the first widely commercially successful fax machine that used linkage bars translating x - and y -axis motion at the receiver to scan a pen across the paper and strike it only when actuated by the stylus moving across the transceiver drum. Because it could use commodity stationery paper, it became popular in business and hospitals. In 1902,
9944-561: The mid-1980s, starting with ThunderScan for the Macintosh in December 1984. Designed by Andy Hertzfeld and released by Thunderware Inc., the ThunderScan contains a specialized image sensor built into a plastic housing the same shape as the ink ribbon cartridge of Apple 's ImageWriter printer. The ThunderScan slots into the ImageWriter's ribbon carrier and connects to both the ImageWriter and
10057-639: The modality gateway interfaces from third party imaging modalities to the Siemens SPI network. The Veterans Administration and the Navy also purchased systems from this contract. In 1993 the third version of the standard was released. Its name was then changed to "Digital Imaging and Communications in Medicine", abbreviated DICOM. New service classes were defined, network support added and the Conformance Statement
10170-492: The modality to send a report about a performed examination including data about the images acquired, beginning time, end time, and duration of a study, dose delivered, etc. It helps give the radiology department a more precise handle on resource (acquisition station) use. Also known as MPPS, this service allows a modality to better coordinate with image storage servers by giving the server a list of objects to send before or while actually sending such objects. The DICOM print service
10283-474: The object to be scanned and reading the intensity and color of light that is reflected from it, usually a line at a time. They are designed for scanning prints or other flat, opaque materials, but some have available transparency adapters, which—for a number of reasons—in most cases, are not very well suited to scanning film. A sheetfed scanner, also known as a document feeder, is a type of scanner that uses motor-driven rollers to move one single sheet of paper at
10396-503: The pendulum; over time, the result is a perfect reproduction of the copper plate. In Bain's system, it is critical that the pendulums of the transceiver and receiver are in perfect step, or else the reproduced image will be distorted. In 1847, the English physicist Frederick Bakewell developed the first working fax machine. Bakewell's machine was similar to Bain's but used a revolving drum coated in tinfoil, with non-conductive ink painted on
10509-422: The process of dye coupling and removal of all silver from the emulsion. Kodak Vision 3 has 18 stops. So, color-negative film scans the easiest of all film types on the widest range of scanners. Because traditional black-and-white film retains the image creating silver after processing, density range can be almost twice that of color film. This makes scanning traditional black-and-white film more difficult and requires
10622-562: The projector-and-photocell arrangement with a video camera tube focusing on one spot of the plate. The first digital imaging system was the Bartlane system in 1920. Named after the pair who invented it, Harry G. Bartholomew and Maynard D. McFarlane, the Bartlane system used zinc plates etched with an image from a film negative projected at five different exposure levels to correspond to five quantization levels. All five plates are affixed to
10735-469: The purest digital representations of the film, followed by high-end film scanners that use the larger Kodak Tri-Linear sensors. The third important parameter for a scanner is its dynamic range (also known as density range). A high-density range means that the scanner is able to record shadow details and brightness details in one scan. Density of film is measured on a base 10 log scale and varies between 0.0 (transparent) and 5.0, about 16 stops. Density range
10848-423: The result of this complexity is a much higher-quality scan. Because CCDs have a much greater depth of field, they are more forgiving when it comes to scanning documents that are difficult to get perfectly flat against the platen (such as bound books). Scanners equipped with contact image sensor (CIS) scanning elements are designed to be in near-direct contact with the document to be scanned and thus do not require
10961-415: The same synchronization issues. In 1862, Giovanni Caselli solved this with the pantelegraph , the first fax machine put into regular service. Largely based on Bain's design, it ensured complete synchronization by flanking the pendulums of both the transceiver and receiver between two magnetic regulators, which become magnetized with each swing of the pendulum and become demagnetized when the pendulum reaches
11074-410: The scan quality is highly dependent on the quality of the phone camera and on the framing chosen by the user of the app. Scans must virtually always be transferred from the scanner to a computer or information storage system for further processing or storage. There are two basic issues: (1) how the scanner is physically connected to the computer and (2) how the application retrieves the information from
11187-482: The scanner for this purpose, actuating if the user is moving the scanner too fast. They typically have at least one button that starts the scan when pressed; it is held by the user for the duration of the scan. Some other handheld scanners have switches to set the optical resolution , as well as a roller, which generates a clock pulse for synchronization with the computer. Older hand scanners were monochrome , and produced light from an array of green LEDs to illuminate
11300-459: The scanner. The file size of a scan can go up to about 100 MB for a 600 dpi, 23 × 28 cm (slightly larger than A4 paper ) uncompressed 24-bit image. Scanned files must be transferred and stored. Scanners can generate this volume of data in a matter of seconds, making a fast connection desirable. Scanners communicate to their host computer using one of the following physical interfaces, listing roughly from slow to fast: During
11413-470: The standard). No information must be extracted from these names (PS3.10 Section 6.2.3.2). This is a common source of problems with media created by developers who did not read the specifications carefully. This is a historical requirement to maintain compatibility with older existing systems. It also mandates the presence of a media directory, the DICOMDIR file, which provides index and summary information for all
11526-471: The suffix "-RS", indicating their RESTful nature. The family consists primarily of: A key feature of the WADO-RS services is the ability to retrieve entire studies and series rather than needing repeated request for individual instances. Other services including support for work lists (UPS-RS) and retrieval of server capabilities. Some very simple examples of URL syntax and meta data encoding are described in
11639-440: The true resolution of a scanner, and is determined by using a resolution test chart. The effective resolution of most all consumer flatbed scanners is considerably lower than the manufactures' given optical resolution. Manufacturers often claim interpolated resolutions as high as 19200 ppi; but such numbers carry little meaningful value because the number of possible interpolated pixels is unlimited, and doing so does not increase
11752-503: The use of these port numbers. According to a paper presented at an international symposium in 2008, the DICOM standard has problems related to data entry. "A major disadvantage of the DICOM Standard is the possibility for entering probably too many optional fields. This disadvantage is mostly showing in inconsistency of filling all the fields with the data. Some image objects are often incomplete because some fields are left blank and some are filled with incorrect data." Another disadvantage
11865-466: The user to provide uniform illumination of the object to be scanned and was more cumbersome to set up. A more modern type of overhead scanner is a document camera (also known as a video scanner), which uses a digital camera to capture a document all at once. Most document cameras output live video of the document and are usually reserved for displaying documents to a live audience, but they may also be used as replacements for image scanners, capturing
11978-554: The web browser. Most recently, a family of DICOM RESTful web services have been defined to allow mobile device friendly access to DICOM objects and services, which include WADO-RS, STOW-RS and QIDO-RS, which together constitute the DICOMweb initiative. There are some derivations from the DICOM standard into other application areas. These include DICONDE ( Digital Imaging and Communication in Nondestructive Evaluation ) that
12091-483: Was a joint effort by DICOM and an ISO working group and was released in 2003 as DICOM Supplement 85 and ISO 17432. The word "persistent" in the name was later dropped. The ISO standard has not been maintained as DICOM PS3.18 has evolved over time. The suffix "-URI" was later added to distinguish what is now called WADO-URI from the newer services. WADO-URI became popular for providing access to both original DICOM files and server side rendered versions of them, and accordingly
12204-530: Was established in 2004 by ASTM International as a way for nondestructive testing manufacturers and users to share image data. DICONDE can be used for computed radiography , digital radiography , computed tomography , ultrasonic testing , and Eddy-current testing ., DICOS ( Digital Imaging and Communication in Security ) that was established in 2009 to be used for image sharing in airport security . DICOM groups information into data sets . For example,
12317-648: Was included in the IHE XDS-I.b profile as one of its required transport mechanisms. After IHE had gone through several revisions of the XDS-I profile, it defined a SOAP-based mechanism for transferring images (the RAD-69 transaction), and this was added to DICOM retrospectively, extended, and became WADO-WS, which was subsequently retired since it was incomplete and not being maintained. As part of DICOM Supplement 118 - Application Hosting, finalized in 2010, an XML "native DICOM model"
12430-559: Was introduced that defined bi-directional transcoding of DICOM datasets between the conventional binary representation and an XML representation. An independent group of developers defined an alternative transport mechanism, Medical Imaging Network Transport (MINT), and proposed it as an extension to DICOM. Though MINT was not adopted in its entirety, the developers were assimilated by DICOM WG 27, and several key features of MINT were defined as extensions to DICOM PS3.18. DICOM Digital Imaging and Communications in Medicine ( DICOM )
12543-420: Was introduced. Initially the DICOM standard was referred to as "DICOM 3.0" to distinguish it from its predecessors. DICOM has been constantly updated and extended since 1993, with the intent that changes are backward compatible, except in rare cases where the earlier specification was incorrect or ambiguous. Officially there is no "version" of the standard except the current standard, hence the "3.0" version number
12656-590: Was made in 1992 by the US Army and Air Force, as part of the MDIS (Medical Diagnostic Imaging Support) program based at Ft. Detrick, Maryland. Loral Aerospace and Siemens Medical Systems led a consortium of companies in deploying the first US military PACS (Picture Archiving and Communications System) at all major Army and Air Force medical treatment facilities and teleradiology nodes at a large number of US military clinics. DeJarnette Research Systems and Merge Technologies provided
12769-598: Was presented at the annual meeting of the Radiological Society of North America (RSNA) in 1990 by these same vendors. Many soon realized that the second version also needed improvement. Several extensions to ACR/NEMA 2.0 were created, like Papyrus (developed by the University Hospital of Geneva, Switzerland) and SPI (Standard Product Interconnect), driven by Siemens Medical Systems and Philips Medical Systems. The first large-scale deployment of ACR/NEMA technology
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