Smartphone-based thermography to determine shunt patency in patients with hydrocephalus

Background: When shunt dysfunction is suspected, radiation exposure due to X-rays or a CT-scan is inevitable. Less-invasive and more reliable methods are warranted. In this study, we aimed to assess the usability of smartphone-based thermography to detect shunt patency in patients with hydrocephalus. Methods: This prospective observational pilot study evaluated the use of smartphone-based video thermography to detect flow of cerebrospinal fluid in the shunt of 51 patients from the Department of Neurosurgery at a tertiary referral institute. Patients with a shunt for hydrocephalus without the suspect of dysfunction were included in the study from December 2021 to May 2022. Results: We included 51 patients with a mean age of 53.3 years. Of these patients 14 were male (27.5%) and 37 were female (72.5%). The most frequent cause of the hydrocephalus was the normal pressure hydrocephalus followed by the congenital hydrocephalus. Most patients (96%) had a ventriculoperitoneal shunt, whereas two had a ventriculo-atrial shunt. In total, 43 patient (84%) had a shunt on the right side and 8 patient (16%) had the shunt located on the left side. In 45 patients (88.2%), we observed a clear flow of cerebrospinal fluid in the cooled shunt trajectory. Conclusions: The findings of this study indicate that in patients with a shunt to treat hydrocephalus, the smartphone-based video thermography may be a safe and simple alternative to show shunt patency without the exposure to radiation.