OA
Global Journal of Clinical Trials
Determination Of Lung Volumes Using Spiral CT During Glossopharyngeal Insufflation
Authors: Olaf Schedler*, Olaf Rusoke-Dierich, O. Kollow, G. Nesterov, C. Ottomann
Publication Year: 2026
Abstract
Glossopharyngeal insufflation (GI, ‘lung packing’) enables experienced freedivers to voluntarily increase the
intrapulmonary gas volume beyond the normal total lung capacity (TLC). The precise, individual quantification of
this additional volume is important for training management, risk assessment and the diagnosis of GI-associated
complications. Spiral computed tomography (spiral CT) with three-dimensional volumetric segmentation
represents a validated, non-invasive method for this purpose; it is already established in diagnostics and can be
methodologically adapted to determine the GI-induced additional volume. This study presents the physiological
principles of GI, the current state of the art in spiral CT-based lung volumetry, and a detailed investigation of
30 freedivers, with the aim of quantifying GI-induced volume changes using CT volumetry, correlating these
with spirometric reference values, and enabling conclusions to be drawn regarding the benefits for competitive
freediving.