Image Management

Image Management in Dentistry

David Gane, DDS, BSc

Copyright 2001 Journal of the California Dental Association.

Dentistry has seen a significant increase in the number of digital imaging technologies that have become commercially available during the past year. Computers, digital still cameras, scanners, intraoral cameras, digital X-ray systems, and their associated imaging software are all positioned at the top of the list of technologies that dentists plan to purchase within the next 12 months. This article provides an overview of the principles of image management in the dental office with an emphasis on hardware and software requirements as well as practical applications that a properly implemented image management system can afford the modern dental office.

Ever since Roentgen’s accidental but momentous discovery of X-rays in 1896, innovative imaging technologies have continued to advance and dramatically improve health care. This is especially true in dentistry, which has seen a significant increase in the number of digital imaging technologies that have become commercially available during the past year. Computers, digital still cameras, scanners, intraoral cameras, digital X-ray systems, and their associated imaging software are all positioned at the top of the list of technologies that dentists plan to purchase within the next 12 months. One reason for this growing popularity of imaging technologies is that they are within the budget of most dentists. Another is that they are easy to use, and they also afford tremendous efficiencies and positive returns to those who invest in them. If we consider this trend toward the use of digital imaging systems combined with the emerging statistics that dentists are computerizing their operatories^3,4 and using the Internet^5,6 in ever greater numbers, a compelling case for adopting digital imaging starts to emerge. This article provides an overview of the principles of image management in the dental office after capture through final output with an emphasis on hardware and software requirements as well as practical applications that a properly implemented image management system can afford the modern dental office.

Digital Images and Their Management

Just like their film-based counterparts (possibly more so), the striking high-resolution digital pictures generated by digital imaging systems are essential and critical elements of a patient’s dental record. These images have proven to be invaluable resources to the dentist for diagnosis, treatment planning, and case presentation. Furthermore, these images are fundamental to optimizing communication with patients, labs, and insurance companies. This sounds very powerful and impressive, but what is a digital image really? The word digital refers to the binary language of computers, bits and bytes. (The use of the numbers 0 and 1 are known as bits, and a byte is eight bits). The computer sees all data, including image files, as binary information. So a digital image is no more than a set of numbers stored as a digital file that a computer can recognize and perform operations on with the help of imaging software. The sheer volume of images that can be acquired in a dental practice can be overwhelming. Managing images from capture to output with the appropriate software ensures that images are stored away carefully by patient name and date so they can be conveniently accessed when needed.

Software

Image management software is essential to maximize the power and convenience of digital imaging. It is routinely used to acquire, store, retrieve, edit, print, and share digital images. A patient’s images are stored in an electronic filing cabinet (image database), along with important information about the image and the patient. While ease of use, specific functionality, and cost vary among different products, the principle is almost always the same.

Images are located by performing a search or browsing though a collection of small images, known as thumbnails, on the computer screen. Once found, an image may be viewed at full size, presented in a slide show format, transferred across a network or the Internet, or printed, alone or as part of an image group. Prices for image management software can vary dramatically. Products offering sophisticated features such as direct digital capture from multiple devices, measurement functionality, annotation, color correction capabilities, etc., have somewhat higher prices. The following points should be considered when evaluating image management software applications for the dental office:

* Image acquisition: Image management software should permit easy transfer of images from the dentist’s image input devices into the patient file in one easy step.

* Image viewing: Much of a dentist’s time with the software will be spent viewing images on screen. The viewing function should enable the user to readily pan and zoom an image as well as view multiple images at once, alone or in a slide-show format.

* Browsing/searching: The image management software should allow the user to organize images in a logical and easy-to-use fashion. The user should be able to locate images by patient, visit date, or image type.

* Printing: The print reports should be versatile. The software should be able to place images on paper in a custom fashion, and there should be a print preview function.

* Database synchronization: A user will often have databases in different places that need to be "synchronized." Image management software should have that capability.

* Software integration: The software being considered should work well with the most current operating systems, e.g., Windows 2000, NT, etc. It is also likely that a dentist will want to use image management in conjunction with practice management software. The image management software should integrate well with other software applications.

* Image editing: The better image management products allow the user to perform certain tasks without switching programs. Such features may include the ability to add notes and comments, color correction, cropping, rotating, resizing, automated measurement, and annotations.

Image Compression

A full-screen 256-color image takes about 1 megabyte of storage, about the same amount as a complete text or Tolstoy’s novel "War and Peace." Color images can consume massive amounts of disk space and memory; they can also be slow to transmit over computer networks. Data compression technology allows large files to be temporarily squeezed so that they take less storage space and transmission time. Before they are used, compressed files must be decompressed. In general, compression works because most raw data files contain redundancy that can be "squeezed out." Lossless compression systems allow a file to be compressed and later decompressed without any loss of data; the decompressed file will be an identical copy of the original file. A popular example of a lossless compression system is WinZIP (DOS/Windows). On the other hand, a lossy system can usually achieve better file compression, but the compressed file isn’t always identical to the original. This is tolerable in many types of image files. A popular example of a lossy system employed by many software developers and vendors is JPEG (Joint Photographic Experts Group).

The Dicom Standard

The Digital Imaging and Communications in Medicine (Dicom) standard as it relates to dentistry is the result of efforts by the American Dental Association Task Group on Dental Informatics and manufacturers to develop a common "language" for formatting and exchanging images and image information throughout the profession.⁶ The emerging Dicom standard will allow dental images to be captured and communicated in a common format, allowing for more efficient exchange of images and related information with the ultimate goal of total interconnectivity among dental and medical images and image-generating devices.⁷ This promises to contain costs and to improve the quality of care. Dicom equipment in an office might include digital intraoral and extraoral radiographic systems, image management software, and secondary capture devices such as intraoral cameras and digital still cameras. The Dicom standard has now been implemented in an increasing number of dental imaging products from various vendors. This adoption of Dicom by the dental industry is opening new opportunities for dentistry to increase the quality and cost-effectiveness of patient care.

There is more to image management software than initially meets the eye. Managing dental images requires easy-to-use, high-quality software. Many practice management software applications do offer varying degrees of imaging functionality, but specialized image management software usually affords greater functionality, usability, and value. A dentist may also wish to consider cosmetic imaging software to provide compelling treatment simulations.

Cosmetic Imaging Software

Cosmetic imaging software (sometimes termed "computer imaging" software) can be used to simulate the results of esthetic and restorative dental procedures. During a case presentation or even during a routine re-care appointment, a patient is able to easily see proposed cosmetic or restorative treatments, such as tooth whitening, prior to committing to a procedure. Cosmetic imaging also allows dentists and their staff to explore different treatment options and to communicate them with their patients in a way never before possible. Using cosmetic imaging software, a dentist or staff member can visually demonstrate what is -- and is not -- feasible. With a clear understanding of patient expectations, any misconceptions can be dealt with prior to treatment. Software options for patient imaging range from inexpensive, general-purpose products to more costly specialized dental simulation programs complete with libraries of teeth to facilitate the imaging process.

One should keep in mind when evaluating options that except for tooth whitening simulations, imaging is generally not performed in front of the patient. The least-expensive image-editing programs available are intended for consumers, photographers, or graphic artists and can be difficult to use for the average dental staff member. Also, these off-the-shelf programs typically do not incorporate image management. Those who can afford the investment are encouraged to consider software that has been developed specifically for dental imaging. The tools and interfaces of these programs are designed to simulate dental treatments in a quick and easy fashion.

Hardware

Prior to purchasing a capture device and software -- i.e., digital camera, scanner, intraoral camera, digital X-ray system, etc. -- one should consider a computer configuration for the clinical workstation. Imaging imposes heavy demands upon a systems resources, both memory and storage. Whether a system be used as a standalone or configured as part of a local area network, the following should be considered when a system is chosen:

* Hard drive: Images files are large files. The bigger the hard drive, the more images that can be stored there. In most cases, 30 Gb of storage will be sufficient.

* CPU: The CPU or processor should meet the specifications of the software that will be used. A speed of 800 Mhz is fine for most clinical imaging applications; the user should get the fastest processor he or she can afford.

* RAM: Random access memory is the computer’s virtual workspace. One should get at least 128 Mb. One can never have too much RAM.

* Printer: A variety of printers are available at different levels of quality and price. Kodak has recently introduced a low-cost digital ink jet printer ideally suited for both high-resolution paper and X-ray film prints.

* Backup: It is important that images are backed up diligently. On a single imaging station, the high capacity and low cost of digital audio tapes makes them an excellent choice. In a network scenario, mirrored hard drives, coupled with a tape backup system, are optimal for uninterrupted access to image data.

* Network card: If computers will be linked in a local area network, a network card will be needed for each computer in the network.

* CD-RW drive (re-writeable): These devices can be external or internal to a computer and are invaluable for moving transferring large amounts of data to a remote location as well as archiving and backing up image data.

* Video card: To capture still video frames into a computer from an intraoral camera will require a video frame grabber card. These inexpensive cards are readily available from software vendors.

* Display: When one is selecting a monitor, the main considerations are screen size (measured diagonally), dot pitch, and refresh rate. Recently there have been major advances in display technology. Cathode ray tube are rapidly being replaced by digital displays. Digital displays offer many advantages over traditional CRT designs in that they can reduce eye fatigue, occupy less desk space, provide a perceived increase in color saturation, and are coming down in price dramatically. Still, the observer’s position relative to the screen greatly influences perceived color rendering. Rather than getting buried in technical aspects, the user should buy the monitor that looks best to him or her.

When one is evaluating a computer system for imaging, expandability is probably the most important consideration. A computer will definitely need to "grow" as the dentist’s understanding and demands of imaging technology grows. There are many good Web sites where a dentist can custom-configure a computer.

Networking

A computer network provides the framework and backbone for achieving complete practice integration, thereby enabling information and images to be accessible throughout the dental office and even at remote locations such as satellite offices and from home.⁸

Local area networks are available in many forms. The most basic is a peer-to-peer-type network As the name implies, all computers in a peer-to-peer-type network are equal. Each computer can access the files and resources of the other, but as a general rule these types of networks are not ideal for imaging applications due to their inability to protect data from unauthorized access as well as the potential for sharing violations and data corruption. It takes a much higher level of sophistication to provide a secured network. This generally means dedicating a computer to act as a "server" for the system to manage the network and image-backup procedures. Realistically, every practice will have its own unique scenario, and the dentist would be wise to consult with a qualified networking professional.

Putting Images to Work

One of the issues that all sophisticated imaging technology dental consumers have to deal with is justifying the cost of purchasing and implementation a new digital imaging system for the office. Digital photography, digital X-ray, intraoral cameras, and computers are all exemplary in their ability to return their investment many times over. In addition, a number of imaging applications provide the ability for the practice to send their images to growing list of insurance companies as electronic attachments to pre-authorizations and claim forms. This affords the practice and insurance company added efficiencies and cost savings that translate into faster claims processing and higher acceptance rates of proposed treatment plans. Images can also easily be shared with lab technicians, specialists, colleagues, and even patients.

Looking Forward

The future of image management will rely heavily on the Internet. As image cameras and X-ray systems become less expensive and more useable and as Internet usage increases and becomes more reliable, companies will soon charge a nominal fee to participate in services such as such as cosmetic imaging, high quality printing, image archive and backup, and differential diagnosis using color and radiographic images. These services will be limited only by the imagination of the service provider. Data centers, service bureaus, image security, and encryption will be the buzzwords of the near future.

Since the introduction of the first radiograph, clinicians have relied upon imaging as an indispensable adjunct to diagnosis and treatment planning. It is no wonder that digital imaging products and image management software make up one of the fastest growing markets in dentistry and are positioned high on the shopping lists of dentists worldwide. When one considers that modern systems are affordable, are easy to use, and dramatically improve patient care and profitability, the question is no longer should one buy into digital imaging but when.

Author

David Gane, DDS, has consulted for a number of universities and corporations with respect to dental imaging technologies and is currently CEO and chairman of Dicom Imaging Systems, Inc. Dr. Gane continues to maintain a part-time practice limited to esthetic dentistry in White Rock, British Columbia, Canada.

References

1. Goldstein CE, Goldstein RE, Garber DA, Imaging in Esthetic Dentistry. Carol Stream, Ill, Quintessence Publishing, 1998.

2. Gane D, Aesthetic Success With The Utilization of Digital Imaging, Practical Periodont Aesthet Dent 12(4):407-8.

3. Trends in dentistry. Dental Products Report June 2000:18.

4. Trends in dentistry. Dental Products Report Dec 2000:34.

5. Web usage increase. Dental Products Report Jul-Aug 2000:57.

6. Subcommittee 3 of the American National Standards Institute/American Dental Association Standards Committee on Dental Informatics.

7. Survey. Dental Products Report Dec 2000:34.

8. American Dental Association, A Step Toward Total Interconnectivity, Dicom and Dentistry. ADA Brochure, Chicago.

9. Goldstein CE, Goldstein RE, Garber DA, Imaging in Esthetic Dentistry. Quintessence Publishing, Carol Stream, Ill, 1998.

Legends

Figures 1a and b. Image management software provides much of the power and convenience of digital imaging and is routinely used to acquire images from a variety of hardware devices as well as to store, retrieve, edit, print, and share the digital images (Images courtesy of Dicom Imaging Systems, Inc.).

Figures 2 a and b. The original image (left) is clear with an uncompressed file size of 510 Kb. The image on the right shows the visible lossy effect of aggressive JPEG compression, but the file is only 28 Kb.

Figure 3. Cosmetic imaging affords the opportunity to explore different treatment options and to communicate them to patients in a way never before possible.

Figure 4. This flow diagram shows a typical work flow for acquiring color images via digital camera and scanner and the potential storage and output solutions (Used with permission of Eastman Kodak).

Figures 5a and b. Easy-to-use image management software puts the power of the images at the dentist’s disposal.