The speech-language pathologists that work in the Orofacial Myology field frequently have patients with nasal obstruction; however, the access to the professional responsible for the diagnosis can be difficult at times. The Peak Nasal Inspiratory Flow is a cheap and easy to handle instrument, broadly cited in the international literature, that has the aim to evaluate nasal patency. The aim of this study was to review the current literature regarding the Peak Nasal Inspiratory Flow, enabling considerations about its use in cervical and orofacial myology disorders. The literature review consulted Medline, Cochrane Library, LILACS and SciELO databases, using the keywords: peak, inspiratory, nasal and flow. The results showed that Peak Nasal Inspiratory Flow is a simple, cheap, validated technique with good reproducibility. Thus, it seems to be an useful instrument to be used in nasal patency evaluation, despite some limitations, providing complementary data to orofacial myofunctional diagnosis. However clinical trials are needed to prove this hypothesis.
Diagnostic techniques, respiratory system; Permeability; Nasal obstruction/physiopathology; Mouth breathing; Nasal cavity/physiology