Systematic anatomical study specifies guidelines for performing nasopharyngeal swabs

Reviewed by Emily Henderson, B.Sc.Aug 10 2021

Since the start of the coronavirus pandemic, thousands of nasopharyngeal swabs have been taken in Austria - millions worldwide. Their correct performance is essential for diagnosing and challenging Covid-19. To assist the correct collection of nasopharyngeal material, a systematic anatomical study conducted at MedUni Vienna specifies guidelines and landmarks and evaluates the danger for the brain.

Inexperienced testers might fail in targeting the nasopharynx mucosa when performing nasopharyngeal swabs to collect material for PCR and antigen tests."

Wolfgang J. Weninger, Study Lead and Head, Division of Anatomy, Center for Anatomy and Cell Biology, Medical University of Vienna

"If the procedure is not performed correctly, material will be taken from the nasal cavity rather than the nasopharynx. In patients with low viral load, this results in shortage of virus material for diagnosis. Infectious people might remain unidentified," said Wolfgang J. Weninger

Published instructions explaining the process of nasopharyngeal swabs are essentially correct. However, the individual anatomy of the nasal cavity and nasopharynx often complicates the performance. The team of anatomists, headed by Wolfgang J. Weninger provides a process and landmarks, which allow testers to securely and successfully perform swabs.

The suggested procedure is based on a systematic scientific study, which simulated nasopharyngeal swabs through both nostrils of 157 body donors. The advancement of the swab was continuously monitored. This allowed proposing a three-stage procedure and landmarks, which allow testers to monitor themselves. The procedure was successful in all individuals without pathologies of the nasal cavity, while procedures based on alternative landmarks were only successful in less than 50%.

Is there a danger for the brain?

Numerous people fear and online fora report a danger for the brain. The anatomy team therefore also investigated the risk of penetrating the thin osseous border between the nasal cavity and the brain when advancing the swab to the nasopharynx. It very clearly turned out that there is no risk of brain injury when nasopharyngeal swabs are performed reasonably correctly.