In This Article
- Researchers at Massachusetts General Hospital are broadening the use of novel optical imaging technology to evaluate the pulmonary airways and lungs
- Melissa Suter, PhD, and colleagues investigate optical coherence tomography (OCT) for in vivo volumetric microscopy
- OCT holds promise for high-accuracy, in vivo diagnosis of lung cancer
- Imaging can now measure the force of contraction, which is essential for helping patients with asthma
Melissa J. Suter, Ph.D, associate professor of Medicine at Harvard Medical School, is working to extend the limits of optical imaging technology to improve early detection, diagnosis and treatment of pulmonary disease. As the lead of the Pulmonary Optical Imaging Laboratory in the Division of Pulmonary and Critical Care Medicine at Massachusetts General Hospital, her team seeks to develop novel optical imaging technology to evaluate the pulmonary airways and lungs.
"Our broad goal is to push technology development to its best clinical utility, whether that be diagnosis, detection, therapy or monitoring in various diseases of the pulmonary airways and lung," says Dr. Suter.
She and her colleagues focus on the use of advanced optical coherence tomography (OCT) imaging technology, for in vivo volumetric microscopy.
Lung Cancer: Early Detection and In Vivo Diagnosis
While CT scans can detect lung cancer, diagnosis which must be done on the microscopic scale is a long-time struggle, says Dr. Suter. OCT is an imaging modality that quickly generates high-resolution (<10 micrometers) cross-sectional images of tissue microstructure, typically to a depth of 2–3 millimeters.
Research from Dr. Suter's lab, published in the Annals of the American Thoracic Society, showed that traditional OCT can diagnose lung cancer in vivo with 80% accuracy, but the goal is to surpass that with increased accessibility and resolution.
Mass General has led the development of major technological advancements in OCT that have greatly increased its clinical utility. These advancements include significant improvements in imaging speed, resolution and contrast and in catheter design. Dr. Suter's team anticipates that advanced endoscopic OCT will enable real-time in vivo diagnosis of pulmonary pathology.
To support that goal, a cross-functional team at Mass General has developed a new class of endoscopic imaging catheters, termed nano-optic endoscopes, that deliver even higher resolution images.
"The images we're getting back are truly diagnostic quality," Dr. Suter says. "My hope is that this will help us in the lung cancer paradox, where early detection by CT is possible, but a diagnosis isn't."
The nano-optic endoscope can also guide biopsy site selection. Dr. Suter says, "the lesions that the CT scan can detect are so small that it's difficult to locate the precise spot to biopsy. Now we can take images of the targeted tissue prior to biopsy."
The team is also incorporating electromagnetic navigation into transbronchial needle catheters. "The same biopsy tool that takes the images and the tissue is also going to have electromagnetic sensors, so it's all in the same instrument to get to the targeted lesions," she says.
In Vivo Assessment of Asthmatic Airways
Prior in vivo optical imaging for patients with asthma produced high-resolution images of structures or tissue composition, but this new technology can also measure function.
"We believe that we can measure the force of contraction just by looking at the properties of light we're getting back," Dr. Suter says.
While her lab focuses on asthma and pulmonary diseases, she says this could apply to all organ systems with smooth muscle. An example of this work in action is with bronchial thermoplasty. In this treatment for poorly controlled asthma, a device ablates the smooth muscle that narrows and constricts the airways.
"Response to this treatment varies widely, so we worked to see if we could use optical imaging to better predict which patients would respond well," says Dr. Suter.
Future Pulmonary Applications of OCT
Endoscopic OCT has been in clinical use for several years, particularly in gastroenterology and interventional cardiology.
"Now in the pulmonary space, it's really beginning to make an impact," says Dr. Suter. "Other centers around the world are also looking into the clinical utilities of this technology for pulmonary medicine."
Although the Pulmonary Optical Imaging Lab focuses primarily on lung cancer and asthma, OCT has applications in other pulmonary diseases.
"It gives clinicians a view of the lung that they've never had before," Dr. Suter says. "And it can happen in vivo in patients, volumetrically and quickly, to help us better understand what's going on."
Dr. Suter's long-term vision is for optical imaging technologies to be a mainstream tool that replaces ultrasound.
"We've developed diagnostic criteria for lung cancer and other pulmonary diseases that we are sharing with other hospitals and universities worldwide so they can better understand how to interpret the images they're getting with OCT," she says. "It does everything that endobronchial ultrasound can do at a higher resolution. Depth penetration may be more of an issue, but in most cases, our technology can do what ultrasound can do—and better—for lung diseases."
Learn more about the Pulmonary Optical Imaging Laboratory
Refer a patient to the Division of Pulmonary and Critical Care Medicine