Assessing nasal airway resistance and symmetry: An approach to global perspective through computational fluid dynamics.

This study aimed to explore the variability in nasal airflow patterns among different sexes and populations using computational fluid dynamics (CFD). We focused on evaluating the universality and applicability of dimensionless parameters R (bilateral nasal resistance) and ϕ (nasal flow asymmetry), initially established in a Caucasian Spanish cohort, across a broader spectrum of human populations to assess normal breathing function in healthy airways. In this retrospective study, CT scans from Cambodia (20 males, 20 females), Russia (20 males, 18 females), and Spain (19 males, 19 females) were analyzed. A standardized CFD workflow was implemented to calculate R-ϕ parameters from these scans. Statistical analyses were conducted to assess and compare these parameters across different sexes and populations, emphasizing their distribution and variances. Our results indicated no significant sex-based differences in the R parameter across the populations. However, moderate sexual dimorphism in the ϕ parameter was observed in the Cambodian group. Notably, no geographical differences were found in either R or ϕ parameters, suggesting consistent nasal airflow characteristics across the diverse human groups studied. The study also emphasized the importance of using dimensionless variables to effectively analyze the relationships between form and function in nasal airflow. The observed consistency of R-ϕ parameters across various populations highlights their potential as reliable indicators in both medical practice and further CFD research, particularly in diverse human populations. Our findings suggest the potential applicability of dimensionless CFD parameters in analyzing nasal airflow, highlighting their utility across diverse demographic and geographic contexts. This research advances our understanding of nasal airflow dynamics and underscores the need for additional studies to validate these parameters in broader population cohorts. The approach of employing dimensionless parameters paves the way for future research that eliminates confounding size effects, enabling more accurate comparisons across different populations and sexes. The implications of this study are significant for the advancement of personalized medicine and the development of diagnostic tools that accommodate individual variations in nasal airflow.

Beyond skeletal studies: A computational analysis of nasal airway function in climate adaptation.

OBJECTIVES: Ecogeographic variation in human nasal anatomy has historically been analyzed on skeletal morphology and interpreted in the context of climatic adaptations to respiratory air-conditioning. Only a few studies have analyzed nasal soft tissue morphology, actively involved in air-conditioning physiology. MATERIALS AND METHODS: We used in vivo computer tomographic scans of (N = 146) adult individuals from Cambodia, Chile, Russia, and Spain. We conducted (N = 438) airflow simulations during inspiration using computational fluid dynamics to analyze the air-conditioning capacities of the nasal soft tissue in the inflow, functional, and outflow tract, under three different environmental conditions: cold-dry; hot-dry; and hot-humid. We performed statistical comparisons between populations and sexes. RESULTS: Subjects from hot-humid regions showed significantly lower air-conditioning capacities than subjects from colder regions in all the three conditions, specifically within the isthmus region in the inflow tract, and the anterior part of the internal functional tract. Posterior to the functional tract, no differences were detected. No differences between sexes were found in any of the tracts and under any of the conditions. DISCUSSION: Our statistical analyses support models of climatic adaptations of anterior nasal soft tissue morphology that fit with, and complement, previous research on dry skulls. However, our results challenge a morpho-functional model that attributes air-conditioning capacities exclusively to the functional tract located within the nasal cavity. Instead, our findings support studies that have suggested that both, the external nose and the intra-facial soft tissue airways contribute to efficiently warming and humidifying air during inspiration. This supports functional interpretations in modern midfacial variation and evolution.

Nasal surgery handled by CFD tools.

Annually, hundreds of thousands of surgical interventions to correct nasal airway obstruction are performed throughout the world. Recent studies have noted that a significant number of patients have persistent symptoms of nasal obstruction postoperatively. In the present work, we introduce a new methodology that raises the success rate of nasal cavity surgery. In this procedure, the surgeon performs virtual surgery on a 3D nasal model of a patient prior to the real surgery. The main goal of the methodology is to guide the surgeon throughout the virtual operation using mathematical estimators based on CFD results. The virtual surgery intervention ends as soon as the estimators fall into a region of a Cartesian coordinate system with a high success probability. This region is defined according to a statistical analysis of estimators corresponding to sets of healthy and diseased cavities. As examples of this application, this study includes 2 surgical operations performed with this innovative methodology on patients with severe nasal obstruction. The patients underwent nasal surgery according to the final nasal geometry revealed by CFD-guided virtual surgery. Currently, both subjects show high degrees of satisfaction.

Virtual surgery for patients with nasal obstruction: Use of computational fluid dynamics (MeComLand®, Digbody® & Noseland®) to document objective flow parameters and optimise surgical results. / Cirugía virtual para pacientes con obstrucción nasal: empleo de un software basado en dinámica de fluidos (MeComLand®, Digbody® & Noseland®) para documentar parámetros objetivos de flujo y optimizar resultados quirúrgicos.

INTRODUCTION: Computational fluid dynamics (CFD) is a mathematical tool to analyse airflow. We present a novel CFD software package to improve results following nasal surgery for obstruction. METHODS: A group of engineers in collaboration with otolaryngologists have developed a very intuitive CFD software package called MeComLand®, which uses the patient's cross-sectional (tomographic) images, thus showing in detail results originated by CFD such as airflow distributions, velocity profiles, pressure, or wall shear stress. NOSELAND® helps medical evaluation with dynamic reports by using a 3D endoscopic view. Using this CFD-based software a patient underwent virtual surgery (septoplasty, turbinoplasty, spreader grafts, lateral crural J-flap and combinations) to choose the best improvement in nasal flow. OBJECTIVE: To present a novel software package to improve nasal surgery results. To apply the software on CT slices from a patient affected by septal deviation. To evaluate several surgical procedures (septoplasty, turbinectomy, spreader-grafts, J-flap and combination among them) to find the best alternative with less morbidity. RESULTS: The combination of all the procedures does not provide the best nasal flow improvement. Septoplasty plus turbinoplasty obtained the best results. Turbinoplasty alone rendered almost similar results to septoplasty in our simulation. CONCLUSIONS: CFD provides useful complementary information to cover diagnosis, prognosis, and follow-up of nasal pathologies based on quantitative magnitudes linked to fluid flow. MeComLand®, DigBody® and NoseLand® represent a non-invasive, low-cost alternative for the functional study of patients with nasal obstruction.

Three new strategies to improve the accuracy of monothermal caloric screening testing.

OBJECTIVE: The objective was to find a way to estimate the value of inter-ear difference (IED) through monothermal caloric screening testing (MCST) that can be used at any laboratory, controlling and minimising the resulting error. METHODS: We retrospectively included in this study 2304 patients from our department to whom a videonystagmography with caloric testing was performed between 2003 and 2011. The IED was calculated in 3 different ways: Using the values of the 4 caloric stimulations (bithermal form) and using only the 2 same-temperature values (warm monothermal and cool monothermal forms). We studied 3 strategies to improve the accuracy of MCST: Analysis of variables that could impair the prediction, delimitation of a grey area of insufficient prediction and location of a maximum utility cut-off point. RESULTS: Correcting Jongkees' formula with the value for spontaneous nystagmus makes it possible to include subjects with spontaneous nystagmus or nystagmus inversion. Establishing 2 cut-off points to classify the subjects avoids approximately 38% of bithermal stimulations performed with a sensitivity and specificity of 95%. Maximum utility was obtained diagnosing as healthy those subjects with IED values lesser than or equal to 16% in warm MCST when the pathological IED was set as greater than 20%. CONCLUSION: New statistical tools help clinicians to make decisions that affect their patients based on the results of MCST.

[Surgical treatment of head and neck squamous cell carcinomas in Spain during the 2006-2011 period]. / Tratamiento quirúrgico de los carcinomas escamosos de cabeza y cuello en España durante el periodo 2006-2011.

INTRODUCTION AND OBJECTIVES: Surgery is one of the basic pillars in the treatment of patients with head and neck squamous cell carcinoma (HNSCC). The objective of the present study was to analyse the current state of the use of surgery in patients with HNSCC in Spain. METHODS: Retrospective review of the hospital discharge reports of the patients with HNSCC treated surgically during the 2006-2011 period in Spain. We obtained the data from the Minimum Basic Data Set during the hospital discharge. RESULTS: We obtained information on 26,629 hospital discharges, with a total of 27,937 surgical procedures. Overall, in our country about half of the patients with HNSCC receive surgical treatment of the primary tumour location. There were no significant changes in the number of surgical procedures throughout the study period. There was a smooth downward trend in the number and percentage of surgeries carried out in male patients, and a significant increase in those carried out in female patients throughout the study period. Among the total of surgical procedures, 15.7% were carried out in hospitals with a low level of complexity, 32.2% in hospitals with an intermediate complexity and 52.1% in centres of high complexity. CONCLUSIONS: Surgery is one essential pillar in the treatment of patients with HNSCC. In Spain about half of the patients with HNSCC receive surgical treatment for the primary location of the tumour.

Wegener's granulomatosis causing bilateral facial paralysis and deafness.

Bilateral facial paralysis (BFP) is an uncommon condition that typically occurs as a manifestation of systemic disease. We present a female patient with Wegener's granulomatosis (WG), particularly upper respiratory and ear impairment who develops hypoacusis and BFP, resistant to immunosuppressive therapy and steroid boluses. Her imaging tests showed no involvement of the facial nerve as it passed through the ear structures. The patient finally improved the BFP; however, deafness is permanent and she has entered into a cochlear implant program. Published papers on BFP are rare and they make no reference to WG as a possible aetiology.

[Ramsay-Hunt syndrome presenting laryngeal paralysis]. / Síndrome de Ramsay-Hunt causante de parálisis laríngea.

The Ramsay-Hunt syndrome is the association of facial palsy and varicella-zoster virus infection with involvement of the ear canal and eardrum. It may be associated with deafness, tinnitus and dizziness. It can sometimes affect the lower cranial nerves. A case of an immunocompetent patient with affectation of the VII, VIII and X cranial nerves is presented.

Cricopharyngeal myotomy in the treatment of oculopharyngeal muscular dystrophy.

Oculopharyngeal muscular dystrophy (OPMD) is an autosomal dominant myopathic disease which provokes oropharyngeal dysphagia, palpabral ptosis and proximal limb weakness. It is the abnormal expression of the GCG triplet in the PABPN1 gene on chromosome 14 that causes this disease. The study of the oropharyngeal dysphagia that these patients suffer from should include upper gastrointestinal endoscopy, barium video-radiology and oesophageal manometry. Genetic study confirms the diagnosis. We report 6 patients (3 of whom were siblings) referred to our department with a confirmed diagnosis of OPMD, who underwent cricopharyngeal myotomy to achieve normal swallowing.

Upper airway distress due to an oropharyngeal infantile myofibroma.

Infantile myofibroma is an uncommon fibrous tumour of infancy, usually present at birth. It is a rare cause of child airway obstruction, with only one neonatal case reported. We report an eight months age case which was referred to our Unit for increasing respiratory distress. CT scan showed a well defined margins mass measuring 7×5×5cm arising from the left parapharyngeal space and occupying the oropharynx. We performed a complete surgical resection through a transoral approach with no events during the surgery. The patient has been followed-up by the first author for five years with no signs of recurrence or sequelaes.

[Benign paroxysmal positional vertigo: analysis of our population and role of caloric tests]. / Vértigo posicional paroxístico benigno: análisis de nuestra población y del papel de las pruebas calóricas.

INTRODUCTION AND OBJECTIVES: Benign paroxysmal positional vertigo (BPPV) is the most common cause of vertigo in those patients who seek medical care. Although videonystagmography seems the most indicated diagnostic test, we tried to decrease the requested caloric tests to optimise resources and reduce associated costs. METHODS: We developed a diagnostic-therapeutic algorithm for patients with suspected BPPV whose provocation tests are positive to evaluate the need for caloric testing. We analysed the results of its application on 98 patients who were referred to our Neuro-otology Unit over 15 months requesting videonystagmography and caloric tests. RESULTS: Only 24% of the requested tests were performed. No significant difference was found in our recurrence rate compared with other series of Spanish patients. CONCLUSIONS: Videonystagmography and caloric tests are not strictly necessary in most patients with BPPV and they should be performed only in patients whose diagnosis is unclear.

[Open-field treatment of hyperacusis]. / Tratamiento de la hiperacusia en campo abierto.

OBJECTIVE: Prospective study of the effectiveness of treatment in patients with hyperacusis by means of an open-field technique of acoustic treatment with nature sounds. MATERIAL AND METHODS: 34 patients were referred to a tinnitus and hyperacusis clinic at a private Otorhinolaryngology Department. Clinical and exploratory ENT studies were performed. Open-field nature sounds were applied by means of a compact disk for half an hour each day during a period of several weeks. RESULTS: By the end of treatment, the 34 patients studied had reached normal discomfort thresholds in a maximum of 9 weeks. CONCLUSIONS: The progressive open-field application of nature sounds has been effective in eliminating hyperacusis in a short space of time.

Sulpiride and melatonin decrease tinnitus perception modulating the auditolimbic dopaminergic pathway.

OBJECTIVES: Sulpiride and melatonin decrease dopamine activity. Sulpiride, a D2 antagonist of dopamine receptors, and melatonin, a pineal substance with antidopaminergic action, are administered to tinnitus patients to decrease tinnitus perception. DESIGN: A prospective, randomized, double-blinded, placebo-controlled study was done. SETTING: General otorhinolaryngologic consultation for 2002-2004 in Seville, Spain. METHODS: One hundred twenty patients consulted for subjective tinnitus. They were included randomly in four groups of 30. One group took sulpiride (50 mg/8 h) alone, the second group took melatonin (3 mg/24 h), the third group took the same doses of sulpiride (50 mg/8 h) plus melatonin (3 mg/24 h), and the fourth group took placebo (lactose 50 mg/8 h), all for 1 month. Ninety-nine patients completed the study. MAIN OUTCOME MEASURES: Clinical history, tonal audiometry, tympanometry, and tinnitometry were done at the beginning and end of the study. Subjective grading of tinnitus perception and a visual analogue scale (0-10) were done for evaluation of results. RESULTS: Based on the subjective grading, tinnitus perception diminished by 56% in patients treated with sulpiride, by 40% in patients treated with melatonin, by 81% in patients treated with sulpiride plus melatonin, and by 22% in patients treated with placebo. Based on the visual analogue scale, tinnitus perception diminished from 7.7 to 6.3 in patients treated with sulpiride, to 6.5 in those treated with melatonin, to 4.8 in patients treated with sulpiride plus melatonin, and to 7.0 in those treated with placebo. CONCLUSIONS: Sulpiride and melatonin reduce tinnitus perception, decreasing dopamine activity. The tinnitus auditolimbic dopaminergic pathway has broad therapeutic implications.

Sulpiride plus hydroxyzine decrease tinnitus perception.

OBJECTIVES: The aim of the study is to confirm the effectiveness of sulpiride and hydroxyzine in tinnitus patients. The administration of sulpiride, a D2 antagonist of dopamine receptors, together with hydroxyzine, a subcortical sedative, covers the areas of tinnitus perception. METHODS: A prospective, randomized, single blinded, placebo-control study was done in general otorhinolaryngology consultations for 2002-2004 in Seville and Zaragoza (Spain). One hundred and fifty patients consulted for subjective tinnitus. They were included randomly in three groups of 50. A group took sulpiride (50 mg/8 h) alone, other the same dose of sulpiride plus hydroxyzine (25 mg/12 h), and the third placebo (lactose), for 1 month. One hundred and twenty-two patients completed the study. Clinical history, tonal audiometry, tympanometry, and tinnitometry were done in the beginning and end of the study. Subjective Grading of Tinnitus Perception and visual analogical scale (0-10) were done for result evaluation. RESULTS: Based on the Subjective Grading of Tinnitus Perception, tinnitus perception diminished by 56% in patients treated with sulpiride and by 81% in patients treated with sulpiride plus hydroxyzine. Based on the visual analogical scale, tinnitus perception diminished from 7.8 to 6.3 in the patients treated with sulpiride, and from 7.8 to 5.1 in those treated with sulpiride plus hydroxyzine. CONCLUSIONS: Sulpiride plus hydroxyzine decreases tinnitus perception. Tinnitus auditolimbic dopaminergic pathway opens wide therapeutical implications.