title: Monte Carlo modeling of light propagation in the human head for applications in sinus imaging.
abstract: Sinus blockages are a common reason for physician visits, affecting one out of seven people in the United States, and often require medical treatment. Diagnosis in the primary care setting is challenging because symptom criteria (via detailed clinical history) plus objective imaging [computed tomography (CT) or endoscopy] are recommended. Unfortunately, neither option is routinely available in primary care. We previously demonstrated that low-cost near-infrared (NIR) transillumination correlates with the bulk findings of sinus opacity measured by CT. We have upgraded the technology, but questions of source optimization, anatomical influence, and detection limits remain. In order to begin addressing these questions, we have modeled NIR light propagation inside a three-dimensional adult human head constructed via CT images using a mesh-based Monte Carlo algorithm (MMCLAB). In this application, the sinus itself, which when healthy is a void region (e.g., nonscattering), is the region of interest. We characterize the changes in detected intensity due to clear (i.e., healthy) versus blocked sinuses and the effect of illumination patterns. We ran simulations for two clinical cases and compared simulations with measurements. The simulations presented herein serve as a proof of concept that this approach could be used to understand contrast mechanisms and limitations of NIR sinus imaging.
authors.affiliation: University of California Irvine, Beckman Laser Institute, 1002 Health Sciences Road East, Irvine, California 92617, United States.
authors.forename: Albert E
authors.initials: AE
authors.lastname: Cerussi
authors.affiliation: University of California Irvine, Beckman Laser Institute, 1002 Health Sciences Road East, Irvine, California 92617, United States.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Mishra
authors.affiliation: Praxis Biosciences, Irvine, California 92617, United States.
authors.forename: Joon
authors.initials: J
authors.lastname: You
authors.affiliation: University of California, Department of Head and Neck Surgery, 101 The City Drive South, Irvine, Orange, California 92868, United States.
authors.forename: Naveen
authors.initials: N
authors.lastname: Bhandarkar
authors.affiliation: University of California Irvine, Beckman Laser Institute, 1002 Health Sciences Road East, Irvine, California 92617, United StatescUniversity of California, Department of Head and Neck Surgery, 101 The City Drive South, Irvine, Orange, California 92868, Un.
authors.forename: Brian
authors.initials: B
authors.lastname: Wong
mesh_terms: D000328:Adult; D000465:Algorithms; D006257:Head / Q000000981:diagnostic imaging*; D006801:Humans; D008027:Light; D008953:Models, Anatomic; D009010:Monte Carlo Method; D010256:Paranasal Sinuses / Q000000981:diagnostic imaging*; D012852:Sinusitis / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed; D014172:Transillumination / Q000379:methods*