X-ray scatter in projection radiography.

Projection radiography is the most common radiological modality, and radiation safety of it concerns both radiation workers and the public. We measured and generated a series of scattered radiation maps for projection radiography and estimated effective doses of the supporting person during exposure. Measured adult patient protocols included chest posterior-anterior, chest lateral, pelvis anterior-posterior (AP), abdomen AP and bedside chest AP. Maps concretise spatial distribution and the scattered radiation dose rates in different imaging protocols. Highest and lowest rates were measured in abdomen AP and bedside chest AP protocols, respectively. The effective dose of supporting person in abdomen AP examination at distance of 0.5 m was 300 nSv and in bedside supine chest AP examination at distance of 0.7 m was 0.5 nSv. The estimated annual effective dose of emergency unit radiographer was 0.11 mSv. The obtained effective dose values are small compared to annual dose limits of radiation workers and the public.

Bioimpedance spectroscopy and spectral camera techniques in detection of oral mucosal diseases: a narrative review of the state-of-the-art.

Oral mucosal diseases are common health problems that reduce overall wellbeing and increase the risk for several systemic diseases. Due to the limitations of present diagnostics, new non-invasive methods are needed for reliable, affordable, real-time screening and follow-up of oral mucosal lesions. Bioimpedance spectroscopy, spectral camera imaging and other optical methods are promising novel techniques to detect abnormal changes in oral mucosa. In this review, the current status of bioimpedance spectroscopy and autofluorescence utilising spectral camera techniques in the assessment of oral mucosal health is critically evaluated. Scientific publications related to bioimpedance spectroscopy were surveyed using PubMed and Scopus databases. Search was done using a combination of terms "oral mucosa", "oral cancer", "squamous cell cancer", "tissue", "electrical impedance measurement" and "bioimpedance spectroscopy". Publications related to spectral cameras were searched from PubMed with a focus on autofluorescence utilising spectral camera techniques. Search was done using terms "autofluorescence", "oral disease" and "VELscope" publication date restricted from 2008 to date. In this review, we also discuss the future trends and strategies such as combining different methods, e.g. spectral cameras and bioimpedance spectroscopy that could represent a unique multimodality in vivo tool for providing complementary information on the health status of the oral mucosa.