OBJECTIVE: The aim of this study was to compare the nasal airway resistance between the cleft and non-cleft sides in operated unilateral cleft lip (UCL) patients with varying severities at birth, as well as to assess the differences in nasal airway resistance between UCL patients and healthy individuals.
METHODS: This retrospective study was conducted on 112 UCL patients who have undergone primary lip reconstructions but not advanced surgeries as the study group and 20 healthy participants as the control group between February 2023 to March 2024. The study group patients were grouped based on the severity of their cleft lip at birth, divided into occult cleft lip group, incomplete cleft lip group, and complete cleft lip group. The anterior rhinomanometry was used to evaluate nasal resistance, including unilateral effective resistances during inspiration (Reffin), expiration (Reffex), and the entire breath (ReffT), as well as unilateral vertex resistance during inspiration (VRin) and expiration (VRex). The Kolmogorov-Smirnov test was used to assess normality. Paired t-tests were utilized to analyze the differences in nasal resistance between the healthy and affected sides within the same group of patients. Student\'s t-test was used to analyze the differences in nasal resistance among patients with different degrees of cleft lip. A p-value of <0.05 was considered statistically significant.
RESULTS: The nasal resistances of the occult cleft and incomplete cleft lip groups showed no significant differences between the cleft and non-cleft sides, and were similar to the control group. However, in the complete cleft lip group, the cleft side nasal resistance was significantly higher than the non-cleft side and control group. Among the groups, the complete cleft lip group had significantly higher nasal resistances on the cleft side for Reffin, VRin, and ReffT compared to the occult cleft group.
CONCLUSIONS: Understanding the nasal resistance of different degrees of operated UCL patients can benefit clinical diagnosis and treatment. Patients with complete cleft lip have more severe nasal obstruction on the cleft side, with greater impact on inhalation than exhalation. For these patients, treatment by an otolaryngologist is recommended to improve nasal airflow.

OBJECTIVE: Investigate the implications of Congenital Nasal Pyriform Aperture Stenosis (CNPAS) on neonatal nasal airflow through computational fluid dynamics (CFD), create a virtual rhinomanometry, and simulate the prospective outcomes post-virtual surgical intervention.
METHODS: CT scanning of a neonate diagnosed with CNPAS and a control model were used to execute CFD simulations. The segmentation file of the CNPAS underwent manual modifications to simulate a virtual surgical procedure, resulting in a geometry that mirrors a post-operatively corrected patient. Virtual rhinomanometry was reconstructed, and airflow dynamics within the nasal cavity were systematically assessed. The results of the three models were compared.
RESULTS: In the CNPAS model, airflow dynamics underwent discernible alterations, with the principal airflow corridor confined to the nasal cavity\'s upper region. There was a marked pressure drop around the nasal valve, and diminished velocities. This first model of virtual surgery has allowed us to observe that the airflow parameters trended toward the control model, reintroducing an airflow trajectory between the lower and middle turbinates. Virtual rhinomanometry presented near-complete nasal obstruction in the CNPAS model, which showed considerable improvement after the virtual surgery.
CONCLUSIONS: CFD highlights the aerodynamic changes resulting from CNPAS. It also allows for the creation of virtual rhinomanometry and the performance of virtual surgeries. Virtual surgery confirms the therapeutic potential of pyriform aperture enlargement techniques used in clinical practice to improve nasal respiratory function. Future research will investigate additional surgical scenarios and the application of these findings to optimize surgical interventions for CNPAS.

Rhinomanometry is a pivotal diagnostic technique in rhinology, providing a quantitative assessment of nasal airflow and resistance. This review comprehensively examines the historical development, principles and clinical applications of rhinomanometry, emphasising its role in diagnosing nasal obstructions, preoperative evaluations and monitoring therapeutic outcomes. Recent advancements, including the integration with imaging technologies and the application of artificial intelligence (AI), have significantly enhanced the accuracy and utility of rhinomanometry. Despite facing challenges such as technical limitations and the need for standardisation, rhinomanometry remains an invaluable tool in both clinical and research settings. The review also explores future directions, highlighting the potential for device miniaturisation, telemedicine integration, personalised protocols and collaborative research efforts. These advancements will likely expand the accessibility, accuracy and clinical relevance of rhinomanometry, solidifying its importance in the ongoing evolution of rhinology practice.

Obstructive sleep apnea (OSA) patients who use continuous positive airway pressure (CPAP) often complain of nasal dryness and nasal obstruction as side effects of CPAP. The physiological mechanisms by which CPAP may cause nasal dryness and nasal obstruction remain poorly understood. It has been hypothesized that CPAP interferes with the nasal cycle, abolishing the resting phase of the cycle and leading to nasal dryness. We performed rhinomanometry measurements in 31 OSA patients sitting, laid supine, and supine after 10 min of CPAP at 10 cmH2O. A posture change from sitting to supine led to more symmetric airflow partitioning between the left and right nostrils in the supine position. CPAP did not have a significant impact on nasal resistance, unilateral airflows, or airflow partitioning. Our results suggest that airflow partitioning becomes more symmetric immediately after changing to a supine position, while CPAP had no effect on nasal airflow, thus preserving the nearly symmetric airflow partitioning achieved after the posture change.

BACKGROUND: This study aimed to determine how nasal airflow measures and trigeminal function vary among patients with chronic rhinosinusitis (CRS) versus healthy controls and whether these measures are correlated with subjective nasal obstruction (SNO), olfactory function, and CRS control.
METHODS: Participants included CRS patients and healthy controls. After a structured medical history, nasal airflow (peak nasal inspiratory flow [PNIF]; active anterior rhinomanometry [AAR]), trigeminal function (trigeminal lateralization test, CO2 sensitivity), and olfactory \"Sniffin\'s Sticks\" odor identification test) tests were performed. SNO ratings were also obtained.
RESULTS: Sixty-nine participants were included (37 men, 32 women, mean age 51 years). There was no significant difference for objective nasal airflow between patients and controls, but CRS patients had worse SNO, trigeminal function, and olfaction compared to controls. SNO, but not objective nasal airflow tests, was negatively correlated with CO2 sensitivity and odor identification.
CONCLUSIONS: The perception of nasal obstruction does not only depend on nasal airflow, but may also be modulated by trigeminal function and other factors. Thus, the role of objective nasal airflow measures as a sole method of functional nasal obstruction assessment in CRS remains limited.

BACKGROUND: Rhinofiller is an aesthetic medical technique that can significantly enhance facial aesthetics by employing hyaluronic acid infiltration. The aim of this study is to review the impact of aesthetic rhinofiller on nasal airflow.
METHODS: This is a retrospective review of 63 consecutive patients. The evaluation of the change in nasal respiratory flow was performed subjectively using a Likert questionnaire and objectively using a rhinomanometer, which enabled active anterior rhinomanometry (AAR). Data were collected at pre-intervention, post-intervention, and at 6-month follow-up.
RESULTS: Among the 63 patients, the questionnaire responses resulted statistically significant both after the treatment and at the 6-month follow-up (p=0.00001). A statistically significant improvement was also observed at the rhinomanometric evaluation between pre-intervention and post-intervention (p=0.006 at 74 Pa, p=0.002 at 100 Pa, and p=0.001 at 150 Pa) and at the 6-month follow-up (p=0.008 at 74 Pa, p=0.003 at 100 Pa, and p=0.002 at 150 Pa). Differences between results were established with a Student\'s t-test. All p-values were two-tailed, and a value < 0.05 was considered significant.
CONCLUSIONS: Rhinofiller can be a valuable aid in enhancing both nasal airflow and facial aesthetics. Based on our experience, it resulted in an immediate post-operative improvement in nasal airflow that remains stable in the subsequent 6 months.
METHODS: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 . IV: Non-Surgical Procedures.

<b><br>Introduction:</b> Rhinomanometry is an otolaryngological diagnostic method used to determine airflow as a function of the pressure drop through the left and right nasal cavities. Airflow is measured using orifice flowmeters that attenuate the flow.</br> <b><br>Aim:</b> This paper describes the results of a study into the effects of flowmeter design on rhinomanometry results and detection of nasal airflow asymmetry.</br> <b><br>Material and methods:</b> Four flowmeters were examined using a 3D printed model of a human nose.</br> <b><br>Conclusions:</b> Each flowmeter interfered with the rhinomanometry results.</br>.

Several methods are available for evaluating nasal breathing and nasal airflow, as this evaluation may be made from several different perspectives.Physiologic methods for nasal airway evaluation directly measure nasal airflow or nasal airway resistance, while anatomical methods measure nasal airway dimensions. Subjective methods evaluate nasal breathing through several validated patient-reported scales assessing nasal breathing. Computational fluid dynamics evaluates nasal airflow through the analysis of several physics\' variables of the nasal airway.Being familiar to these methods is of utmost importance for the nasal surgeon to be able to understand data provided by the different methods and to be able to choose the combination of evaluation methods that will provide the information most relevant to each clinical situation.

Assessing patients with complaints of nasal obstruction has traditionally been done by evaluation of the nasal airway looking for fixed or dynamic obstructive locations that could impair nasal airflow. Not infrequently, however, symptoms of nasal obstruction do not match the clinical examination of the nasal airway. Addressing this subset of patients may be a challenge to the surgeon. Evaluation of patients with symptoms of nasal obstruction should include a combination of a patient-reported assessment of nasal breathing and at least one objective method for measuring nasal airflow or nasal airway resistance or dimensions. This will allow distinction between patients with symptoms of nasal obstruction and low airflow or high nasal airway resistance and patients with similar symptoms but whose objective evaluation demonstrates normal nasal airflow or normal airway dimensions or resistance. Patients with low nasal airflow or high nasal airway resistance will require treatment to increase nasal airflow as a necessary step to improve symptoms, whereas patients with normal nasal airflow or nasal airway resistance will require a multidimensional assessment looking for less obvious causes of impaired nasal breathing sensation.

Impairment of nasal breathing is a highly prevalent and bothersome symptom that affects daily functioning and/or sleep quality. Those surgeons dealing with patients seeking rhinoplasty need to carefully analyze the preoperative nasal breathing capacity and predict the positive or even negative impact of rhino(septo)plasty on nasal breathing. Given the lack of correlation between the subjective feeling of suboptimal nasal breathing and the objective measurements of nasal flow and nasal resistance, a critical and mainly clinical evaluation of all anatomical, mucosal, and sensory mechanisms involved in nasal obstruction is mandatory. Indeed, thermo-, mechano-, and chemosensory receptors on the nasal mucosa, airflow, and respiratory dynamics might all contribute to the overall perception of nasal breathing capacity. In this review, we provide an overview of the factors determining suboptimal nasal breathing including different diagnostic and experimental tests that can be performed to evaluate nasal flow and nasal resistance and current limitations in our understanding of the problem of nasal breathing in an individual patient. An algorithm for the preoperative or diagnostic workup for nasal obstruction is included that might be useful as a guide for clinicians dealing with patients seeking nose surgery.