Researchers at Stanford University, in collaboration with scientists at the German Cancer Institute, have shown for the first time that shortwave infrared (SWIR) imaging can be used to visualize injectable filler materials during injection laryngoplasty, a common procedure used to treat vocal fold paralysis and other forms of glottic insufficiency. The findings , published in Otolaryngology–Head and Neck Surgery , of this novel visualization technique could pave the way for precision-guided techniques in laryngeal surgery.
“Shortwave infrared (SWIR) imaging can be a game-changer for injection laryngoplasty because it enables real-time, high-contrast visualization of injected materials beneath the mucosa, allowing precise localization, improved accuracy of vocal fold augmentation, and immediate confirmation of treatment adequacy,” Tulio A. Valdez, MD, MSc, corresponding author and Professor of Otolaryngology - Head & Neck Surgery at Stanford Medicine.
The research team used a custom SWIR imaging system operating in the 1000–2000 nm wavelength; they found that imaging at 1550 nm produced significantly greater contrast between vocal fold tissue and surrounding respiratory mucosa compared to visible light - likely driven by differences in water content between the two tissue types.
The combination of reflection and fluorescence SWIR imaging offers a multimodal approach that could help surgeons confirm correct filler placement in real time, identify misplaced superficial injections, and potentially monitor filler resorption over time.
While the study was conducted in a laboratory setting using ex vivo tissues, the authors note that the optical setups could be integrated into endoscopes or operating microscopes for clinical use. The cost of SWIR camera technology has decreased substantially in recent years, making broader clinical adoption increasingly feasible.
Beyond injection laryngoplasty, the researchers suggest SWIR imaging could have future applications in identifying vocal fold pathologies such as cysts and polyps, differentiating layers of the vocal fold based on water and collagen content, and detecting areas of laryngeal inflammation.
Study Citation: Park, R.K., Lee, M.C., Härtl, S., Arús, B.A., Nuyen, B., Sung, C.-K., Baik, F.M., Bruns, O.T. and Valdez, T.A. (2026), Multimodal Shortwave Infrared Imaging for Visualization of Injection Laryngoplasty. Otolaryngol Head Neck Surg , 174: 185-194. https://doi.org/10.1002/ohn.70050
Otolaryngology–Head and Neck Surgery
Otolaryngology–Head and Neck Surgery (OTO Journal) is the official peer-reviewed publication of the American Academy of Otolaryngology–Head and Neck Surgery Foundation. Our mission is to publish contemporary, ethical, clinically relevant information in otolaryngology, head and neck surgery (ear, nose, throat, head, and neck disorders) that can be used by otolaryngologists, clinicians, scientists, and specialists to improve patient care and public health.
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The AAO-HNS/F is one of the world’s largest organizations representing specialists who treat the ears, nose, throat, and related structures of the head and neck. Otolaryngologist-head and neck surgeons diagnose and treat medical disorders that are among the most common affecting patients of all ages in the United States and around the world. Those medical conditions include chronic ear disease, hearing and balance disorders, hearing loss, sinusitis, snoring and sleep apnea, allergies, swallowing disorders, nosebleeds, hoarseness, dizziness, and tumors of the head and neck as well as aesthetic and reconstructive surgery and intricate micro-surgical procedures of the head and neck. The Academy has approximately 13,000 members. The AAO-HNS Foundation works to advance the art, science, and ethical practice of otolaryngology-head and neck surgery through education, research, and quality measurement.
Otolaryngology
Multimodal Shortwave Infrared Imaging for Visualization of Injection Laryngoplasty
17-Oct-2025