For the last few months, family physician Dr. R. Russell Thomas Jr. has split his time between visiting patients at his practice in Eagle Lake, Tex., and treating children who reside more than 300 miles away in Sheffield, Tex. via telemedicine. His virtual tool belt includes an electronic stethoscope that enables Dr. Thomas to hear a patient’s heartbeat in real time and a high-definition camera to view and diagnose skin lesions.

The telehealth services are part of a new initiative at Rice Medical Center, a 25-bed, critical access hospital in rural Eagle Lake – population 3,700. Dr. Thomas has thus far used the technology to treat patients at an at-risk children’s academy and a local primary school. Soon, he and other physicians will also use telemedicine to consult with cardiologists and internists who practice 70 miles away in Houston.

“I look at telemedicine not so much as a practice like cardiology or orthopedics, but more [as] a tool like a percussion hammer or an otoscope,” Dr. Thomas said in an interview. “It’s a tool to practice whatever it is that you do.”

Dr. Thomas is far from alone. Analysts predict vast growth in the telemedicine industry in the coming years. The number of health providers offering telemedicine is expected to rise from 22% in 2014 to 37% in 2015, according to research by Towers Watson. Another report , by BCC Research, shows the global telehospital/clinic and telehome market is expected to reach about $43 billion in 2019, up from $19 billion in 2014.

The explosion of telemedicine is driven by two primary factors, said Dr. Joseph P. McMenamin , a Richmond, Va., attorney who specializes in medical malpractice defense and telemedicine.

“As a society, we are increasingly reliant upon and enamored of electronic methods of communications,” Dr. McMenamin said in an interview. “In one sense, it’s just part of a larger trend. The other, more specific reason, perhaps, is the widespread dissatisfaction with the way our health care system operates today. We are blessed in the United States to have some of the finest physicians in the world. … and then we have this terribly complex, burdensome system for getting people to where they need to be to get care. Telemedicine, by comparison is quick, convenient, and relatively inexpensive.”

But for doctors, the practice of telemedicine is strewn with challenges. Barriers include reimbursement, licensing, malpractice, and regulation. Topping the barriers is a lack of uniform standards about practices. A key question: What constitutes the responsible use of telemedicine?

States have differing ideas. Some require a physical examination by a physician prior to telemedicine. Some allow that encounter can be conducted via telemedicine, while others mandate the visit is in-person. Alabama, Georgia, and Texas require an in-person follow-up visit after a telemedicine encounter, according to 2015 data from the American Telemedicine Association (ATA). Sixteen states and D.C. have informed consent requirements for telemedicine patients. Still other states have no defined rules for the practice of telemedicine.

To promote consistency and better usage, the Federation of State Medical Boards in 2014 issued a model policy to state medical boards about the recommended practice of telemedicine. The policy maintains that the same standard of care applied to face-to-face encounters be applied to telemedicine encounters, said Lisa A. Robin, chief advocacy officer for the Federation of State Medical Boards (FSMB). At least 29 state boards have telemedicine rules that are consistent with the model policy, Ms. Robin said in an interview.

“As telemedicine continues to evolve, we believe there must be a very strong focus on ensuring patient safety through sound policy making and regulatory practices,” she said.

From practice debate to court dispute

Medical specialty societies are beginning to weigh in on acceptable telehealth practices for doctors. In July, the American Academy of Pediatrics issued guidance advocating that use of telemedicine for episodic care should be done within the context of the medical home and that fragmented telemedicine services should be avoided. Guidance issued by the American Medical Association makes it clears that physicians who prescribe using telemedicine need to first establish a patient-physician relationship. In September, the American College of Physicians (ACP) also issued policy in support of expanded telemedicine use, but cautioned the practice should be between a physician and patient who have an established relationship. The FSMB guidance also states that doctors should establish a relationship with patients before practicing telemedicine.

But how that relationship is created is up for debate. In Texas, disagreement over what creates a physician-patient relationship has led to litigation between national telemedicine company Teladoc and the Texas Medical Board. The case centers on a medical board rule that requires physicians to have a face-to-face visit with patients before treating them through telemedicine. The relationship can be created through telemedicine at an established medical site, but it may not be established through an online questionnaire, e-mail, text, chat, or telephonic evaluation or consultation. Teladoc sued the medical board in April claiming the rule violates federal antitrust laws. Teladoc provides access to medical care via phone or interactive video and treats patients for nonemergency conditions. A judge halted the rule’s enforcement in May.

The company sued to ensure patients have access to the same high-quality telehealth care they’ve received for decades, said Teladoc CEO Jason Gorevic.

“We have employers, health plans, and hospital systems who are coming to us because telehealth is a solution to access-to-care challenges as well as a mechanism to control the cost of care,” Mr. Gorevic said in an interview. “It was our responsibility and quite frankly, our obligation, to take action where they were regulations being adopted that were counter to the interests of patients, payers, and physicians in the state.”

In an April statement, Dr. Michael Arambula , president of the Texas Medical Board (TMB), said the rule represents the best balance of convenience and safety by ensuring quality health care for patients.

“The board recognizes that as technology evolves, so too must regulations governing telemedicine,” Dr. Arambula said in the statement. “However, a telephone medicine scenario that allows a physician to treat an unknown patient without any objective diagnostic data and no ability to follow up with the patient sacrifices the patient’s safety for convenience.”

The Texas Medical Association (TMA) supported the TMB rule. Dr. Thomas, a former TMB member who is active with the TMA, said the rule’s logic is simple.

Without a face-to-face visit, “the doctor has no knowledge of the patient, except for what they tell you in that one encounter,” he said in an interview. “There are no follow-up opportunities, no mechanism for further assessment. It’s episodic care at its worst.”

However, Dr. Reed V. Tuckson, president of the American Telemedicine Association, stresses rules such as the Texas Medical Board’s are unnecessarily intrusive to doctors and diminish the range of possibilities for telemedicine care.

“We do not believe the restrictive covenants that are being applied by far too many state medical boards are appropriate,” Dr. Tuckson said in an interview. “We do not believe they should dictating to physicians, the tools that they should be able to use in partnership with their patients to meet [patients’] individual needs.”

Coming Tuesday, Sept. 29: Who leads the field on paying for telemedicine services?