As Google Glass gains momentum as a potentially useful health care tool, a new study reports that the wearable computer demonstrated both benefits and drawbacks during a monthlong test in a children's hospital.

Physicians have extolled the virtues of Glass, and startups are developing ways to use it in clinical settings, but the study, which recently appeared in International Journal of Surgery, is one of the first systematic evaluations of the device to be published in medical literature.

Dr. Oliver Muensterer, a pediatric surgeon at Maria Fareri Children's Hospital of Westchester Medical Center in New York, obtained Glass through Google's "explorer" program and wore it daily during rounds, in the clinic and in the operating room for four consecutive weeks last year. Overall, the paper's authors wrote, colleagues, staff, families and patients "overwhelmingly had a positive response" to the device.

Muensterer found Glass useful for taking hands-free photos and videos of patients' conditions, making hands-free telephone calls, looking up billing codes and searching the Internet for unfamiliar medical terms or syndromes, which the voice recognition software correctly identified about half the time ("Google, what is Hirschsprung disease?"). He could also take notes for later by saying, for example, "Take a note: completely necrotic bowel, decided to close abdomen."

But in other ways, Glass couldn't keep up. On a typical day, the battery lasted between 8.5 and 10 hours, but teleconferencing or continuous video recording drained it much more quickly. The Glass wearer had difficulty hearing audio through the device "in all but the quietest environments," and he also had to speak loudly to be heard on the other end.

The doctor and his coauthors also encountered privacy concerns - an issue that has kept Glass from being fully accepted in public and social situations. Protected health data is typically automatically synced to a Google server when Glass is hooked up to a wireless connection, and the authors were worried that data could potentially be transferred to an unprotected server outside the hospital. In this case, the authors avoided such a breach by temporarily deactivating the Internet connection and deleting all patient data before the automatic synchronization could happen.

Many patients were excited and curious about the high-tech glasses. Others, however, "were concerned that Glass could be filming or recording them clandestinely," the authors wrote.

In conclusion, "Google Glass has some clear utility in the clinical setting, and foreseeably a great potential to favorably impact medical and surgical practitioners in their daily activities," the authors said. "However, there are significant drawbacks in the current design and performance of the device in the healthcare environment."

Since the study was conducted, Google has improved the battery life and other features in Version 2.0 of Glass, which went on a one-day, $1,500 sale to the public Tuesday. The tech giant is also encouraging people to use the device specifically in workplaces such as doctor's offices.

©2014 the San Francisco Chronicle