Vol. 103 No. 5 May 2007

EDITORIAL

Image communication: Mailed, wired, and wireless

The film was then processed chemically.

One of the advantages of analog dental x-ray filmradiographs is that they are perfectly interoperable, i.e.,they can always be viewed providing there is a suitablelight source for transillumination. Communication ispossible without translation; however, it means thephysical delivery of the radiograph by a courier or inthe mail if they need to be transferred geographicallywithout the added step of scanning for wired or wirelesstransmission. Unlike original digital images, neitherfilm digitization nor film-based duplication provides anidentical clone of the original image.

So when did electronic long-distance transfer of den-tal images commence? While the actual date is uncer-tain, you might be surprised to learn that there arerecords of the electronic transmission of dental filmradiographs published by the Eastman Kodak Corpora-tion early in 1929—transmission was via the WesternUnion Telegraph.1 The radiographs were scanned andcoded; then this code was translated to light to exposefilm at the receiving end of the wire (Fig. 1). The imagewas then processed chemically to provide the duplicatedental radiographs.

Fast forward until 1991: that year solid-state dentalradiographs were transmitted between the BellSouthResearch Center in Louisville, Kentucky, and theGrand Rex Theatre in Paris, France, where the inventorof the RVG (RadioVisioGraphy) system, FrancisMouyen, was making a presentation as part of theFrench Dental Association Annual Session. Transmis-sion via the then new ISDN system took 4 seconds (Fig.2), following 5 minutes of a busy signal due to limitedline availability at that time . . . and the special produc-tion of a computer board to allow the AT&T ISDNstandard to communicate with the international ISDNstandard used in Europe . . . and a transatlantic flight byFrancis Mouyen to deliver a board in time for thedemonstration (after one sent earlier had been held upin customs in Indianapolis because of limited hours ofoperation). One year later the Internet linked Louisville,

Kentucky, with the 2nd Digital Radiography in Den-

Fig. 1. Image transmission on the wire using the WesternUnion Telegraph system was reported early in 1929. Theanalog film radiograph was scanned and the film densitycoded. The code was transmitted and then converted to lightintensities for exposure of analog film at the receiving end.

585

OOOOE586 Editorial May 2007

tistry Congress run by Paul van der Stelt at ACTA,(Academisch Centrum Tandheelkunde Amsterdam),Amsterdam, The Netherlands. Transmission and recon-struction time was 32 seconds. Hard to imagine now,but such transmission held the fascination of an audi-ence of oral and maxillofacial radiologists. Hard tobelieve that at this time the WINDOWS operatingsystem was a newborn operating system not even in itsinfancy.

Nowadays, it is not the transmission of images that isdifficult. Almost everyone is able to send JPEG andTIFF digital camera images over the Internet and trans-mission times are very short given the widespreadavailability of wideband services. These, however, arehopefully not medical images subject to HIPAA andother privacy rules, nor are they in proprietary formatsthat cannot be interchanged between systems. Youwould be very unwise to send the digital images ofyour patients as simple e-mail attachments, althoughDICOM Supplement 113 (2006) shows the way. Secu-rity measures are important, involving encryption andrestricted opening of the transferred files. Loss of pa-tient privacy can lead to significant fines and otherpenalties.

We are no longer in the age of the Western Uniontelegraph; the last telegraph was sent some 2 yearsbefore the publication of this editorial. Patient informa-tion now needs secure encryption before it can becommunicated electronically. And before it can be in-teroperated accurately between imaging systems itneeds to be encoded in a file type that is standard. That

Fig. 2. In 1991, live teletransmission was effected of digitalcommunication between the BellSouth Telecommunication Ring at the Grand Rex Theatre in Paris as part of the French Dseconds. Left, Francis Mouyen visiting Kentucky in 1991; Rhistogram of pixel intensity values.

file format is ISO referenced and is DICOM. Unfortu-

nately, not all vendors of digital systems are widelydistributing DICOM conformant systems, perhaps be-cause they want to keep you hostage to their proprietarysystems. This is contrary to American Dental Associa-tion promotion of the DICOM standard and promotionof digital interoperability.

So you are still a “computer-Luddite,” with no desireto become digital? Then be willing to retire in 2010-2015! In that time frame, you will be expected to makeyour insurance submissions with all attachments—in-cluding radiographs—as digital and follow the ASCX12 protocol. This transition might well be greater fordental practice than Y2K and previous HIPAA require-ments combined. If you are not entirely digital forimaging already, this is the time to plan for the transi-tion. Alternatively, you could simply hand the profes-sion to the next generations. The secure transmission oflarge data sets of DICOM format images is becomingcommonplace as cone beam volumetric computed to-mography is enabling fabrication of surgical guides andvirtual models to facilitate dental implant placementand other dental surgical procedures. Transmission ofpatient image data sets is generally via secure ftp.

Allan G. Farman, BDS, PhD, DSc, MBAEditor, Oral and Maxillofacial Radiology

doi:10.1016/j.tripleo.2006.12.034

REFERENCE

s from the RVG 32000 system using early ISDN telephoneCenter, Louisville, Kentucky, and Francis Mouyen present-

Association Annual Congress. The transmission time was 4ne of the transmitted images reconstructed into a 3D color

imageesearch

entalight, O

1. Anonymous. Sending dental x-rays by telegraph. Dent RadiogPhotog 1929;2(1):1-2.