Anatomical Insights on the Cervical Nerve for Contemporary Face and Neck Lifting: A Cadaveric Study.

BACKGROUND: Despite the significant roles it plays in the functions of the platysma and lower lip, the cervical branch of the facial nerve is often overlooked compared to other branches, but its consideration is critical for ensuring the safety of neck surgeries. OBJECTIVES: The aim of this study was to clarify the anatomical discrepancies associated with the cervical branch of the facial nerve to enhance surgical safety. METHODS: The study utilized 20 fresh-frozen hemiheads. A 2-stage surgical procedure was employed, beginning with an initial deep-plane facelift including extensive neck dissection, followed by a superficial parotidectomy on fresh-frozen cadavers. This approach allowed for a thorough exploration and mapping of the cervical nerve in relation to its surrounding anatomical structures. RESULTS: Upon exiting the parotid gland, the cervical nerve consistently traveled beneath the investing layer of the deep cervical fascia for a brief distance, traversing the deep fascia to travel within the areolar connective tissue before terminating anteriorly in the platysma muscle. A single branch was observed in 2 cases, while 2 branches were noted in 18 cases. CONCLUSIONS: The cervical nerve's relatively deeper position below the mandible's angle facilitates a safer subplatysmal dissection via a lateral approach for the release of the cervical retaining ligaments. Due to the absence of a protective barrier, the nerve is more susceptible to injuries from direct trauma or thermal damage caused by electrocautery, especially during median approaches.

Deep Neck Contouring With a Focus on Submandibular Gland Vascularity: A Cadaver Study.

BACKGROUND: Opening the neck through a submental incision allows accurate management of deep neck structures and results in exceptional neck contours. OBJECTIVES: The authors aimed to evaluate the distribution of deep neck structures and investigate the detailed vascular anatomy of the submandibular gland. METHODS: A total of 26 fresh frozen cadaver heads (15 female, 11 male) were utilized. The authors evaluated the weights of the excised tissues simulating cosmetic resections, including subcutaneous fat, subplatysmal fat, the anterior belly of the digastric muscle, and submandibular glands. The vascular supply of the submandibular gland and intracapsular vessel diameters were also investigated. RESULTS: Whereas female cadavers had greater mean tissue weight removed from the supraplatysmal plane (mean 20.9 g, 56.6%) than the subplatysmal plane (16 g, 43.4%), male cadavers had higher mean tissue weight removed from the subplatysmal plane (10.5 g, 60.7%) than the supraplatysmal plane (mean 6.8 g, 39.3%). The mean subcutaneous (6.8 g) and subplatysmal (6.4 g) fat weights were almost equal in male cadavers; mean subcutaneous fat weight (20.9 g) was 3 times higher than subplatysmal fat weight (6.8 g) in female cadavers. There was a statistically significant relationship between body mass index and fat removed. The intraglandular vessel diameters increased as resections approached the main feeding vessels located posterosuperior (facial artery) and anterosuperior (submental artery) to the submandibular gland. CONCLUSIONS: The results suggest that to achieve exceptional neck contour the structures deep to the platysma often need to be addressed. The submandibular gland reduction can be safely performed with comprehensive understanding of its vascular anatomy.

Comparison of the efficacy of two different local anesthetics in inferior turbinate reduction.

PURPOSE: The present study compares the local anesthetic efficacy of EMLA® cream and lidocaine injection used in the radiofrequency reduction of the inferior turbinate. METHODS: The study included a total of 124 patients with inferior turbinate hypertrophy and who underwent turbinate reduction under local anesthesia. The operations were performed 15 min after a lidocaine injection and 30 min after EMLA cream application. The respondent patients were asked to interpret such situations as intraoperative pain, discomfort during the procedure, choking sensation and difficulty swallowing using the Visual Analogue Scale (VAS). RESULTS: The EMLA cream patients (Group A) were found to have a lower level of discomfort, choking sensation and difficulty swallowing than the lidocaine patients (Group B), while there was no substantial difference in pain between the two groups. CONCLUSIONS: It is concluded that EMLA® cream is an effective alternative to lidocaine injection during inferior turbinate reduction procedures.

Age- and Gender-Related Variability in Nasal Tip Support.

BACKGROUND: The age at which nasal tip support changes start to occur is unknown. Evaluation of nasal tip support is difficult, especially as the ideal nasal tip support pressure remains elusive. The aim of this study is to determine the nasal tip support pressure alterations relative to age and sex. OBJECTIVES: The aim of this study is to determine the changers in resistance of the nasal tip support in relation to age and sex. METHODS: This prospective clinical study was conducted between January and April 2019 at a tertiary health facility. Nasal tip resistances were measured in four different age-groups (20-29, 30-39, 40-64, and > 65 years) with a digital Newton meter. A total of 159 patients with a minimum of 36 patients per group were included in the study. Nasal tip resistance measurements were compared among nasal tip displacement distances of 2, 3, and 4 mm, focusing on age and sex. RESULTS: The nasal tip resistance of the 20-29 age-group was significantly higher at 2, 3, and 4 mm nasal tip displacement distances, when compared with the 30-39 and 40-64 age-groups, whereas compared to the > 65 years group, it was significantly higher at 3 and 4 mm nasal tip displacement distances (p < 0.005). Nasal tip resistance of males was found to be significantly higher than that of females, at 3 and 4 mm nasal tip displacement distances (p < 0.001). CONCLUSIONS: Nasal tip resistance is higher in males and universally decreases significantly after 30 years of age while remaining constant at later ages. Therefore, surgeons should prefer nasal tip resistance increasing techniques in the rhinoplasty operations that are performed on patients even from early years of age, in order to maintain and strengthen the nasal tip resistance. LEVEL OF EVIDENCE IV: 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.

An Overlooked Landmark for the Crooked Nose: Eyebrow Position.

BACKGROUND: Rhinoplasty is one of the most unforgiving operations in facial plastic surgery. The correction of nasal deviation in an asymmetrical face can be challenging because known facial landmarks may mislead the surgeon. Eyebrows trimmed asymmetrically in an effort to create a more symmetrical facial appearance may be overlooked by surgeons. OBJECTIVE: To define the relationship between the eyebrow position and external nasal deviation in patients with a crooked nose. DESIGN, SETTING, AND PARTICIPANTS: Analysis was made of the preoperative and 6-month postoperative life-size photographs of female rhinoplasty patients who had been referred to the senior author's clinic between May 2014 and June 2019. The anthropometric landmarks on the life-size photographs were identifed. The most medial points of the eyebrows and most deviated part of the nose were marked and the distance from the mid-canthal point was measured. MAIN OUTCOMES AND MEASURE: The direction and amount of eyebrow shift were compared with the direction and amount of nasal deviation. RESULTS: Of the total 94 female rhinoplasty patients with at least one level external nasal deviation, 67 (71.2%) had ipsilateral eyebrow shift with external nasal deviation. The preoperative external nasal deviation amount was 1.81 ± 1.21 mm and preoperative eyebrow shift was 1.18 ± 1.06 mm (rS = 0.429, p < 0.001). The postoperative nasal deviation was 0.79 ± 0.92 mm, and the eyebrow shift was 0.54 ± 0.62 mm (rS = 0.570, p < 0.001). CONCLUSION AND RELEVANCE: Patients may tend to trim their eyebrows towards the side of the external nasal deviation. After centralization of the crooked nose with rhinoplasty, asymmetric eyebrow shaping tendencies of the patients were also seen to be improved. LEVEL OF EVIDENCE IV: 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 .

Comparison of Rapid Absorbable Sutures with Nonabsorbable Sutures in Closing Transcolumellar Incision in Septorhinoplasty: Short-term Outcomes.

BACKGROUND: Following open rhinoplasty, a postoperative scar at the columellar incision line is a common morbidity. The aim of this study is to compare absorbable and nonabsorbable suture materials which had been used for closing the transcolumellar incision, in the aspect of risk of postoperative infection, wound healing, postoperative columellar scar and patient satisfaction. METHOD: A prospective, randomized, single-blind study was conducted between May 2017 and February 2018. Sixty-four rhinoplasty patients were randomly assigned to absorbable (n = 32) or nonabsorbable (n = 32) groups. The columellar incision was closed with 7 full-thickness skin sutures. Either nonabsorbable 6/0 polypropylene (Group 1) or absorbable 6/0 polyglytone 6211 (Group 2) sutures were placed at the columellar incisions. Polypropylene sutures were removed at the 7th postoperative day. A Mann-Whitney U test and Monte Carlo were used for statistical comparison. Photographs of the patients at the postoperative third month (Fig. 2) were evaluated and scored in terms of scarring, pigmentation, notching, level differences in the incision area by two different otorhinolaryngologists who did not know the randomization. Suture removing discomfort was assessed with visual analogue scale scores. A satisfaction survey was filled out by all the patients completing their third month after the operation. RESULTS: According to the results of both otorhinolaryngologists, there was no significant difference between the two groups in terms of pigmentation, level difference, notching, overall appearance and total score (p = 0.920, p = 0.498, respectively). The mean score on the Wong-Baker scale was 3.19 ± 1.67 in group 1. In the Satisfaction Survey, the average score of the group 1 was 6.90 ± 3.24, while the mean score of the group 2 was 7.062 ± 2.77. There was no statistically significant difference between the two groups (p = 0.715). CONCLUSIONS: Suturing inverted V transcolumellar incisions with rapid resorbable sutures caused significantly less discomfort but no difference in scarring compared to nonresorbable sutures as evaluated by patients and observers. LEVEL OF EVIDENCE III: 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 .

Evaluation of Nasal Tip Support in Septorhinoplasty.

BACKGROUND: A good understanding of nasal tip support mechanisms is essential for achieving successful and functional rhinoplasty results. The loss of nasal tip support resulting from different maneuvers adopted during rhinoplasty and how this loss is affected by reconstructive applications should be known. This study evaluated and compared changes in nasal tip support perioperatively after different techniques were used during septorhinoplasty. METHODS: Patients who underwent primary open rhinoplasty between January 2018 and March 2018 in a tertiary medical center were included in this prospective blind case series. Nasal tip resistance measurements were taken after perioperative maneuvers by creating enough force to achieve 1 mm, 2 mm and 3 mm of displacement at the tip region. Measurements were obtained during six different stages using a Newton meter: preoperatively, after caudal septal resection, after skin flap elevation, after the columellar strut or tongue-in-groove procedure, after tip suturing and postoperatively. Our hypothesis was that during septorhinoplasty, each maneuver used changes the tip support intraoperatively. The predictor variables were the different rhinoplasty techniques used. The outcome variable was nasal tip resistance to compression intraoperatively and immediate postoperatively. Appropriate statistics were computed, and a p < 0.05 value was considered significant. RESULTS: Ten of the 15 patients were female, and 5 were male. The patient age ranged from 19 to 40 (mean 24.8 ± 4.9). The tongue-in-groove technique was applied in 5 of the patients, while columellar strut grafting was performed in 10. The application of columellar strut grafting did not create a significant increase in nasal tip support (p > 0.05). An increase in nasal tip support was observed at each stage (85%, 53%, 35%) after application of the tongue-in-groove technique (p < 0.05). CONCLUSIONS: A novel and reproducible technique for digitally evaluating manual force is presented for determining changes in nasal tip support with different maneuvers applied in living patients undergoing rhinoplasty. No significant difference was noted between the preoperative and postoperative measurements for columellar strut grafting. The tongue-in-groove technique is an important maneuver that has a significant effect on nasal tip support. According to our data, the interdomal and intercrural ligaments, the medial crus-septum connections and the connections between alar cartilage and overlying skin and muscle tissue are important structures for tip support. LEVEL OF EVIDENCE IV: 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 .

Endoscopic modified medial maxillectomy for treatment of inverted papilloma originating from the maxillary sinus.

Endoscopic approaches have become an alternative to external approaches in the treatment of sinonasal inverted papillomas (IPs) in recent years. The aim of this study was to analyze the outcomes of endoscopic modified medial maxillectomy preserving the nasolacrimal duct and the inferior turbinate in selected IP cases. Medical charts of patients diagnosed with IP originating from the maxillary sinus between July 2008 and August 2013 were reviewed. Eight patients who had undergone endoscopic modified medial maxillectomy were included in the study. Attachment of IP was located on the medial wall of the maxillary sinus in all cases. The nasolacrimal duct was preserved in all of the patients. The inferior turbinate was completely preserved in 5 patients, and the anterior part of the inferior turbinate was preserved in 3 patients. The mean follow-up period of the patients was 30.8 months (12-60  mo). None of the patients had recurrence or major complications. The postoperative complaints were minor hemorrhagic discharge and crusting for the first few weeks. Endoscopic modified medial maxillectomy preserving the nasolacrimal duct and the inferior turbinate provides good surgical and functional outcomes in selected IP cases.

Vestibular functions in motion sickness susceptible individuals.

There exists no functional guide that can serve as a diagnostic tool for individual susceptibility to motion sickness (MS). We evaluated vestibular system functioning via a caloric test (which assesses functioning of the superior vestibular nerve) and the vestibular-evoked myogenic potentials (VEMP) test (which assesses inferior vestibular nerve functioning) in 20 MS susceptible and 20 nonsusceptible individuals. Susceptibility to MS was determined by self-declaration and with MS susceptibility questionnaire and Hamilton Anxiety Scale (HAS). We found statistically significant differences for scores on the MS susceptibility questionnaire and HAS questionnaire; however, we found no correlation between VEMP and caloric test results. We suggest that VEMP and caloric test results are not affected by individuals' susceptibility to MS. We could not find vestibular system deficits using the VEMP and caloric test combination. Our findings do not support vestibular function asymmetry in MS patients.

Otorhinolaryngologic Problems in Liver and Kidney Transplant Recipients.

OBJECTIVES: The aim of this study was to define the otorhinolaryngologic manifestations and clinical characteristics of patients who received kidney or liver transplants at a university hospital. MATERIALS AND METHODS: Medical records of patients who received a kidney or liver transplant between 2000 and 2013 and who were referred or applied to the ear, nose, and throat clinic were retrospectively reviewed. Otorhinolaryngologic complaints, signs, examination findings, and diagnoses of patients were noted. RESULTS: Our analyses included 540 visits to the ear, nose, and throat clinic by 101 liver and 191 kidney transplant recipients. Mean duration between date of transplant and otorhinolaryngologic examination was 747.9 ± 37.1 days. The most common complaint was rhinorrhea (n = 112), whereas the most common diagnosis was acute rhinosinusitis (n = 85). Acute upper respiratory tract infections, including rhinosinusitis, were diagnosed more frequently during the late postoperative period (ie, > 180 days after transplant). Epistaxis was more frequent during the first 30 days after transplant. CONCLUSIONS: A diverse variety of otorhinolaryngologic conditions, including emergencies and potentially life-threatening infections, were seen in our kidney and liver transplant recipients, both during the early and the late follow-up period. All transplant team members should be familiar with the clinical presentation of frequently seen otorhinolaryngologic diseases.

Crushed cartilage grafts for concealing irregularities in rhinoplasty.

OBJECTIVE: To assess the clinical outcome of crushed cartilage grafts used to conceal contour irregularities in rhinoplasty. METHODS: We reviewed the medical records of 462 patients in whom crushed autogenous cartilage grafts were used, selected from a total of 669 patients in whom rhinoplasty procedures were performed at our institution between June 1, 1999, and June 1, 2006. The grafts were used as slightly, moderately, significantly, or severely crushed. RESULTS: Eight hundred nine cartilage grafts (41 slightly crushed grafts [5%], 650 moderately crushed grafts [80%], and 118 significantly crushed grafts [15%]) were used in 462 patients. Resorption occurred in 11 of the 462 patients (2.4%). All of the resorbed grafts (6 moderately crushed grafts and 5 significantly crushed grafts) had been placed in the dorsal area. The resorption rate of those grafts was lower in the moderately crushed cartilage grafts (6 of 284 grafts [2.1%]) than in the significantly crushed grafts (5 of 38 grafts [13.1%]). There was no resorption of slightly crushed grafts. CONCLUSIONS: The degree of crushing applied is important for long-term clinical outcome of autogenous crushed cartilage grafts. Slight or moderate crushing of cartilage creates an outstanding graft material for concealing irregularities and provides both excellent long-term clinical outcome and predictable esthetic results.

Seborrheic keratosis of the nasal vestibule.

Seborrheic keratosis is a common hyperkeratotic lesion of the epidermis, that usually occurs in the trunk and less frequently in the extremities, face, and the scalp. Occurrence in the nasal vestibule has not been reported in the literature. An 80-year-old woman presented with a long-standing, slowly growing, firm, red-brown polypoid mass, 0.5 cm in size, located at the skin-mucosa interface of the right nasal vestibule. The lesion was excised under local anesthesia and histopathologic examination showed seborrheic keratosis that mimicked squamous cell carcinoma. There was no recurrence during a-year follow-up.

[Multiple myeloma of the sphenoid sinus: a case report]. / Sfenoid sinüs multipl miyelomu: Olgu sunumu.

Plasma cell neoplasms of the head and neck region can be extramedullary plasmacytoma of the bone, solitary plasmacytoma of the bone, and local manifestations of multiple myeloma. A 70-year-old male patient was admitted to our hospital with diplopia of four-day history. Magnetic resonance imaging showed soft tissue in the sphenoid sinus. Endoscopic biopsy was taken from the sphenoid sinus, which revealed multiple myeloma. Despite medical therapy for multiple myeloma, the patient died after a year.

A comparative study on nasal packing after septoplasty: does it matter in terms of patient comfort, bleeding, and crust or synechia formation?

OBJECTIVES: This study aims to compare pain, bleeding, nasal obstruction, crust and synechia formation, and anesthesia-related morbidity in patients with and without use of nasal packs after septoplasty. PATIENTS AND METHODS: A total of 66 patients (32 women, 34 men; mean age 24 years; range 18 to 48 years) who underwent Cottle's septoplasty under general anesthesia were randomly allocated to three groups in this prospective cohort. Telfa nasal packs were used in sutures + telfa group (n=22) and Merocell nasal packs in merocel alone group (n=22). No packs were administered in sutures alone group (n=22). Three groups were compared in terms of nasal obstruction, bleeding, pain, crust and synechia formation, as well as the amount of secretion, the need for oropharyngeal airway, the presence of laryngospasm, and effort for nasal breathing after anesthesia. RESULTS: The amount of bleeding was higher with lower degree of nasal obstruction in sutures alone group. Pain and secretion were more remarkable in merocel alone group. After the first week, these differences were unable to be differentiated among the groups. There were no differences between three groups with respect to crust and synechia formation two weeks after septal surgery. CONCLUSION: Nasal packs can be more useful in patients who suffer from bleeding-related morbidity, while septoplasty applied without nasal packs can be more suitable in patients with obstructive sleep apnea. The use of nasal packs in septoplasty should be determined on an individualized basis with respect to the characteristics of each patient.

[The relationship between passive rhinomanometry measurements in sitting and supine position and obstructive sleep apnea syndrome]. / Oturur ve sirtüstü pozisyonda pasif rinomanometri ölçümleri ve tikayici uyku apne sendromu ile iliskisi.

OBJECTIVES: This study aims to investigate the possible relationship between passive rhinomanometry measurements in sitting and supine position and obstructive sleep apnea syndrome. PATIENTS AND METHODS: Between January 2011 and December 2013, 88 male patients (mean age 46.8 years; range 18 to 79 years) underwent passive rhinomanometry in sitting and supine position following history, physical examination and fiberoptic endoscopic examination. 1.5 lt/sn air flow was pumped into the nose of each patient via a silicone nasal mask. Meanwhile, flow and pressure values were measured. RESULTS: There was no correlation between the resistance values and apnea hypopnea index (AHI) scores and polysomnography and physical examination parameters (p>0.05). The differential resistance was correlated with AHI (r=0.325, p<0.05), body mass index (r=0.324, p<0.05), neck circumference (r=0.421, p<0.01), waist circumference (r=0.444, p<0.01), modified Mallampati score (r=0.356, p<0.05), and retropalatal grade (r=0.438, p<0.01). CONCLUSION: The correlation between the differential resistance and physical examination parameters and AHI scores support the hypothesis that position-related retropalatal segment alterations can be measured by passive rhinomanometry while awake.

Viability of crushed and diced cartilage grafts: a study in rabbits.

OBJECTIVE: To investigate the effects of dicing and different degrees of crushing on cartilage graft viability and outcome in rhinoplasty. METHODS: Cartilage was harvested from both ears of 29 rabbits. For each animal, 6 cartilage pieces were prepared as follows and inserted into the paraspinal subcutaneous tissue: (1) left intact, (2) diced to approximately 1 x 1-mm pieces and then wrapped in oxidized regenerated cellulose, (3) slightly crushed, (4) moderately crushed, (5) significantly crushed, and (6) severely crushed. Animals were killed at 2, 5, and 10 months, and graft specimens were microscopically examined. RESULTS: As crushing intensity rose, cartilage viability decreased and more cartilage tissue was transformed to connective tissue. The intact and slightly crushed grafts showed significant chondrocyte proliferation. This decreased as crushing intensity increased, and the severely crushed and diced cellulose-wrapped grafts exhibited almost no peripheral chondrocyte proliferation. CONCLUSIONS: Slight crushing of a cartilage graft can produce outstanding graft material that forms softer nasal contours and fills defects well. However, severe crushing of cartilage grafts results in extensive necrosis and eventual reduction in graft volume. The use of oxidized regenerated cellulose to wrap diced cartilage grafts also tends to reduce clinical predictability owing to negative effects on cartilage viability and regeneration.

Viability of cultured human nasal septum chondrocytes after crushing.

OBJECTIVE: To investigate how different degrees of crushing affect the viability of human nasal septum chondrocytes in adherent cell cultures. METHODS: Cartilage grafts were harvested from the nasal septa of 15 patients who underwent submucosal resection. Five cartilage pieces were prepared from each specimen as follows: the cartilage was left intact, slightly crushed, moderately crushed, significantly crushed, or severely crushed. Chondrocytes were isolated for trypan blue dye exclusion testing, and the numbers of viable cells were determined at 1, 2, 3, and 10 days after culturing. Comparisons were made among the groups. RESULTS: The day 1 viability rates for the intact, slightly crushed, moderately crushed, significantly crushed, and severely crushed cartilage preparations were 96%, 92%, 82%, 72%, and 54%, respectively. The corresponding rates on day 10 were 93%, 90%, 84%, 75%, and 68%. CONCLUSIONS: The viability and proliferative capacity of crushed human septal cartilage depend on the degree of crushing sustained. Slightly or moderately crushed cartilage grafts show good chondrocyte viability and proliferation and are valuable for fashioning soft nasal contours, filling defects, and concealing dorsal irregularities. However, significant or severe crushing reduces chondrocyte viability and proliferation and may result in unpredictable degrees of graft volume loss.

Isolated fibrous dysplasia of the sphenoid sinus.

Fibrous dysplasia is an uncommon benign bone disorder of unknown etiology in which normal medullary bone is replaced by fibrotic and osseous tissue. Solitary involvement of the sphenoid sinus is unusual. Here, we present the case of a 28-year-old man complaining of occipital and vertical headache. Imaging modalities demonstrated an expansile lesion filling the entire sphenoid sinus. Biopsy specimen was obtained by endoscopic sphenoidotomy. Diagnosis of fibrous dysplasia was made by imaging results and pathologic examination.

Skin problems following septorhinoplasty.

OBJECTIVES/HYPOTHESIS: Septorhinoplasty is one of the most commonly performed plastic surgery procedures in the world. Studies on septorhinoplasty in the literature mainly focus on the surgical procedures and their outcomes, but the general appearance of the nose and nasal skin following surgery is also very important. STUDY DESIGN: Case-control study examining 30 septorhinoplasty patients and 20 septoplasty patients for postoperative skin conditions. RESULTS: There were significant differences identified between the septorhinoplasty group and the septoplasty group with respect to their mean preoperative Global Acne Grading System, Seborrheic Dermatitis Area Severity Index, and visual analog scores (acne, seborrhea, and ecchymosis). CONCLUSIONS: The aim of study was to identify and evaluate postoperative skin conditions among septorhinoplasty patients, as well as the progression and duration of treatment of these conditions. LEVEL OF EVIDENCE: 3b.

Effects of paranasal sinus ostia and volume on acoustic rhinometry measurements: a model study.

We used pipe models to investigate the effects of paranasal sinus ostium size and paranasal sinus volume on the area-distance curves derived by acoustic rhinometry (AR). Each model had a Helmholtz resonator or a short neck as a side branch that simulated the paranasal sinus and sinus ostium. The AR-derived cross-sectional areas posterior to the ostium were significantly overestimated. Sinus volume affected the AR measurements only when the sinus was connected via a relatively large ostium. The experimental area-distance curve posterior to the side branch showed pronounced oscillations in association with low-frequency acoustic resonances in this distal part of the pipe. The experimental results are discussed in terms of theoretically calculated "sound-power reflection coefficients" for the pipe models used. The results indicate that the effects of paranasal sinuses and low-frequency acoustic resonances in the posterior part of the nasal cavity are not accounted for in the current AR algorithms. AR does not provide reliable information about sinus ostium size, sinus volume, or cross-sectional area in the distal parts of nasal cavity.