Telepathology allows Mohs surgeons to consult with dermatopathologists in real time, so they can confirm their management strategies with these experts or even alter the strategies, according to a recent study.
The study published in Dermatologic Surgery in January 2007 found dynamic telepathology, which uses telecommunications technology to transmit histologic images, was effective in confirming diagnoses made by Mohs surgeons.
"The consultation is going on during the case," says Jeffrey McKenna, M.D., a Mohs surgeon in private practice in Media, Pa., a former fellow in procedural dermatology at the University of Vermont in Burlington, Vt., and the study's lead author. "There is downtime following the surgery, where the patient is in the waiting room and we can consult with a dermatopathologist."
Mohs surgeons do not necessarily have ready access to dermatopathologists if they are not based near an academic center, Dr. McKenna explains.
"There are instances where you'd like a second opinion as to the status of a tumor," Dr. McKenna says. "Many Mohs surgeons in private practice may not have such access. Using telepathology allows them that access. The (iChat AV, Apple Computer) videoconferencing software is relatively inexpensive to use."
The caveat to making this application a reality in practice is that Mohs surgeons and dermatopathologists need to have broadband Internet access to ensure that images can be transmitted in real time with adequate quality to decipher skin lesions. The bandwidth needs to be at least 100 Kbps for video transmission.
Dial-up service is 56 Kbps, so users would need either a digital subscriber line or cable modem connection to meet the minimum system requirements. Academic institutions and most private practice offices are equipped with high-speed connections that surpass these bandwidth requirements.
"If you don't have high bandwidth, it won't be successful. If the image looks pixilated, that is no good," Dr. McKenna tells Dermatology Times.
In the first part of the study, 20 unknown formalin-fixed, paraffin-embedded slides from tumors seen in a Mohs practice were assessed by the consultant dermatopathologist. In the second part of the study, the Mohs surgeon consulted the dermatopathologist on 20 Mohs frozen section slides about which the surgeon had a specific question, such as whether a tumor was a basal cell carcinoma or a section part of a pilosebaceous unit.
The complexity of the questions asked, and the need for consultations in general, would depend on the relative experience level of the individual Mohs surgeon. Dr. McKenna notes a second opinion generally is reassuring, and it can be helpful to draw on the expertise of dermatopathologist colleagues.
The study was a proof-of-concept design aimed at assessing whether images would be resolute enough so that dermatopathologists receiving the images via the Internet could identify the lesions, according to Dr. McKenna.
"We were not testing the ability of the dermatopathologist or the surgeon," Dr. McKenna says. "We weren't trying to determine if they can identify a basal cell carcinoma or not. We were using simple cases to test if the technology worked. It would not make sense to go ahead with the set- up if the dermatopathologist had trouble distinguishing the images that are relatively simple to identify. We want to be able to ask more complex questions in the future, for example: does a tumor invade a nerve fiber, or whether a Mohs section shows true melanoma in situ or just persistent atypical melanocytic proliferation."
The dermatopathologist examined video images on a standard PowerBook G4 laptop computer with a 17-inch screen. Internet access was provided via the University of Utah local area network (LAN) connection with a data transmission capacity of up to 100 MBps.
During videoconferencing, the Mohs surgeon and consultant dermatopathologist are in direct communication using the microphone on the computer. Only the histologic video images are transmitted over the Internet, with no patient-identifying information attached.