Validation of Thermal Imaging to Detect Pneumonia

I. BACKGROUND AND SIGNIFICANCE

1. Historical Background

Every day 16,000 children under the age of 5-years die. Although strides have been made in early diagnosis and treatment of pneumonia, it still accounts for about 15% of deaths of children under 5-years (1). Unfortunately care providers in low- and middle-income countries (LMICs) are limited due to lack of resources and training. Chest x-rays are especially difficult to obtain in these LMICs (14). Ironically, smartphones are readily available. Since its development in 1960, Forward-Looking Infrared (FLIR) cameras have made several technological strides. Notably they are now more affordable and compact, attaching to smartphones. FLIR cameras now have the potential to aid in early diagnosis and subsequent treatment of childhood pneumonia.

FLIR imaging was first developed in 1956 with military funding at the University of Chicago. From the 1960s into the 1970s, FLIR technology was modified independently by both the Air Force and Texas Instruments Inc. for use by military planes (2). Wendell Smith first documented the use of thermal imaging in medical diagnosis in 1964. Smith required 6 minutes to take each thermograph of the horses he was studying (3). Multiple veterinary studies have been performed since then, and now thermal imaging has been validated as a means to assess musculoskeletal injuries in animals (4,5). 2. Previous Clinical Studies Supporting the Proposed Research

Interestingly, very few clinical studies have been performed to validate the use of thermal imaging in medical diagnosis for human diseases. The use of thermography to diagnose lung disease was studied in Russia in 1976, 1981, and 1991 in three separate studies, but these studies were neither controlled nor randomized (6-8). In 1970 Potanin demonstrated through a case series that patients with pneumonia had increased overlying chest temperatures and patients with pulmonary embolism had decreased overlying chest temperatures (12). The most recent and impactful study evaluating pneumonia with thermal imaging was a case series performed by Wiecek et al. (2001), which showed that patients with pneumonia demonstrated a reduction in thermographic signal as they positively responded to treatment (13). More modern studies have attempted to validate infrared thermal imaging in measuring the size of brain tumors intra-operatively (9), screening for fever in children (10), and predicting length of recuperation after burn injuries (11), among others. However, there has not been a modern study validating thermal imaging in diagnosing pneumonia. 3. Rationale behind Proposed Research and Potential Benefit to Society