Hyperaeration of the frontal sinus

The nasal cavity and paranasal sinuses constitute an anatomical and functional unit. Paranasal sinuses communicate with the nasal cavities, which are covered by the same mucosa, via small openings and narrow ducts that allow both aeration and sinus drainage. Anatomical variations of the paranasal sinuses and nasal cavity are important in sinus diseases. Computerized tomography (CT) plays a critical role in evaluation of the patients with paranasal sinus pathology and variations. A 38-year-old man admitted to our clinic with headache and postnasal dripping for 1 year. His paranasal CT scanning revealed that there is hyperaeration of the frontal sinus which is in continuity with the sphenoid sinus. Hyperaeration of the sinuses may be kept in mind in a patient complaining of headache.     

A study on collagenase production of nasal polyp-derived fibroblasts stimulated by nasal secretions of chronic sinusitis

The collagenase produced by mesenchymal cells has been thought to have a great importance in the pathophysiology of connective tissue metabolism and prolongation of chronic inflammation. The factors, such as IL-1 and PMN factor, released by inflammatory cells have been known to induce mesenchymal cells to produce collagenase. In the present study, the collagenase activity of the nasal secretions were estimated using FITC-labelled collagens as substrates. The factor, enhancing the fibroblasts to produce collagenase, was also isolated from nasal secretions and partially characterized. The fibroblasts used in the present study were cultured with explant of the sections of nasal polyp obtained from a patient with chronic sinusitis. The collagenase activity in nasal secretions from patients with chronic sinusitis was high, whereas that of allergic nasal secretions was extremely low. Furthermore, the collagenase productions of nasal polyp-derived fibroblasts were enhanced by the extracts of nasal secretions from patients with chronic sinusitis. Crude extracts of nasal secretions were fractionated by ammonium sulfate precipitation. The active materials precipitated by 50% to 80% ammonium sulfate were further purified by Sephadex G-75 gel chromatography. The molecular weight determination of the active fraction checked by HPLC utilizing for TSK 2,000 SW gel column indicates 20,000 daltons for the active materials. However, the collagenase production of human microvascular endothelial cells derived from nasal mucosa was not enhanced by this factor. Although either the origin or the nature was not confirmed, the factor was considered to relate to the prolongation of chronic inflammation in the nasal and paranasal sinus pathology. Analysis of these factors will expected to establish methods for new therapeutics in chronic inflammation.     

Study of ethmoid sinus involvement in multibacillary leprosy

The nasal mucosal involvement in lepromatous leprosy is well recognized. Currently interest has centred around the involvement of paranasal sinuses in leprosy. They act as a reservoir and constant source of reinfection to the nasal mucosa. In the present prospective study 25 untreated patients with multi-bacillary leprosy were included. Clinical examination, computed tomography (CT) scan of paranasal sinuses, ethmoid sinus endoscopy and biopsy were carried out in all patients, to investigate the involvement of the paranasal sinuses in leprosy. Ethmoid sinus involvement was noted in 20 patients on CT scan. Bilateral involvement was more common (65 per cent). Anterior ethmoids were more commonly affected (65 per cent). On ethmoid sinus endoscopy abnormal mucosa was noted in 17 patients (68 per cent). Ethmoid sinus biopsy was confirmative in 16 patients (64 per cent). Statistically significant correlation was found between CT findings, sinus endoscopy and sinus biopsy findings.     

Density of epithelial cells in the normal human nose and the paranasal sinus mucosa. A scanning electron microscopic study

214 biopsies of mucosa from various sites of the nose and paranasal sinuses were obtained post-mortem and examined using the scanning electron microscope. The density of ciliated cells was increased in the nasal cavity, in the antero-posterior direction. In paranasal sinuses the density of these cells was high, except near the ostium of the maxillary sinus, where the density was decreased by half. Non-ciliated epithelial cells were found in relatively few areas: anterior aspect of the middle and lower turbinates, anterior septum. However, no uniform distribution of these cells was present. The density of goblet cells was significantly lower in the paranasal sinuses as compared to the nasal cavity, with the highest density being found near the ostium of the maxillary sinus.     

Nasal polyposis (or chronic olfactory rhinitis)

The concept of chronic rhinosinusitis with or without polyps is founded on the structural and functional unicity of the pituitary mucosa and its united response to environmental aggression by allergens, viruses, bacteria, pollution, etc. The present review sets this concept against the evo-devo three-nose theory, in which nasal polyposis is distinguished as specific to the olfactory nose and in particular to the non-olfactory mucosa of the ethmoid, which is considered to be not a sinus but rather the skull-base bone harboring the olfactory mucosa. The evo-devo approach enables simple and precise positive diagnosis of nasal polyposis and its various clinical forms, improves differential diagnosis by distinguishing chronic diseases of the respiratory nose and those of the paranasal sinuses, hypothesizes an autoimmune origin specifically aimed at olfactory system auto-antigens, and supports the surgical concept of nasalization against that of functional sinus and ostiomeatal-complex surgery. The ventilation function of the sinuses seems minor compared to their production, storage and active release of nitric oxide (NO) serving to oxygenate arterial blood in the pulmonary alveoli. This respiratory function of the paranasal sinuses may indeed be their most important. NO trapped in the ethmoidal spaces also accounts for certain radiographic aspects associated with nasal polyposis.     

Nasal polyposis and facial pain

A cohort of 973 patients with symptoms of rhinosinusitis and/or facial pain was followed up for a mean of 2 years 2 months and, within this, was a group of 220 with nasal polyps. Only 39 (18%) had pain or pressure as a symptom. Out of the 220 with nasal polyps, 190 had polyps without any purulent secretions and, of these, only 5 (2.6%) had pain attributable to their paranasal sinus disease. Ten out of the 15 with pain and polyps without pus were found to have pain as a result of neurological or medical cause after endoscopic sinus surgery and a trial of medical nasal treatment and, where necessary, drugs to treat neurological conditions. Thirty patients (13.6%) had nasal polyposis and purulent secretions, and, within this subgroup, 24 (79%) had pain as well. Of the 24 with pain and purulent secretions, 19 (80%) responded to treatment for their paranasal sinus disease, a far higher proportion than with nasal polyps without pus. In conclusion, in patients who have nasal polyps without purulent secretions, be cautious about attributing any symptoms of facial pain or pressure as being due to their paranasal sinuses as it is more probable that it is coincidental and the result of a neurological cause.     

Updating nasalisation: From concept to technique and results

Nasalisation is a surgical technique proposed for the treatment of nasal polyposis in 1995. The technique as initially described was based on large opening of the maxillary, sphenoidal and frontal ostia and resection of the middle turbinates, with the aim of resecting the mucosa of the lateral masses of the ethmoid as completely and safely as possible. Recent findings on the evolution and development of the nose and sinuses and sinus physiology allow both the concept and the technique of nasalisation to be updated. According to evo-devo theory, the ethmoid is not a paranasal sinus but the skull-base bone housing the olfactory mucosa. In humans, the olfactory mucosa can be distinguished as functional in the upper recess of both olfactory clefts and vestigial in the rest of the ethmoid bone. Nasal polyposis presents clinically as a specific disease of the vestigial olfactory mucosa of the human ethmoid (and not as a particular kind of chronic rhinosinusitis). The aim of surgery for nasal polyposis is thus maximal resection of the vestigial olfactory mucosa, conserving olfactory function as long as possible. By the production, storage and bolus release of nitric oxide thanks to the sphincter function of the paranasal (maxillary, sphenoidal and frontal) sinus ostia, the paranasal sinuses perform a respiratory function that should be conserved as much as possible. The nasalisation technique has been modified in order for the vestigial olfactory mucosa to be completely resected while sparing the sinus ostia. Middle turbinate surgery still needs to be evaluated: resection is a step toward maximal removal of vestigial olfactory mucosa, while conservation could ensure olfactory cleft integrity. Thus, updating the concept of nasalisation enables the nasalisation technique to be integrated in the evo-devo concept of rhinology.     

New data on nasal morphology and morphological structure of paranasal sinuses

The authors summarize the results of investigations of specific anatomical features of paranasal sinuses in more than 12,000 subjects. The patients with suspected cerebral pathology and lesions in the paranasal sinuses were examined using computed tomography. Structural variants of ethmoid bone and ethmoidal labyrinth, nasal septum, maxillary, frontal, and sphenoidal sinuses are described. The morphometric analysis revealed the zonal relationship between different structures of nasal mucosa and the new variants of regulatory structures in the cavernous sinus vessels.     

鼻腔鼻窦非霍奇金淋巴瘤的CT表现

目的：探讨鼻腔鼻窦非霍奇金淋巴瘤（ＣＨＬ）的ＣＴ影像学特征,方法：对９例经病检确诊为鼻腔鼻窦ＮＨＬ患者的ＣＴ片进行回顾性分析。结果;原发于鼻腔鼻窦的ＮＨＬ在临床上有着典型的恶性特征,但在ＣＴ影像上所表现的骨质破坏,类似于良性病变的骨改建、骨膨胀性改变,而非其他恶性肿瘤那样表现为侵入性骨质破坏;其在鼻腔内形成均匀软组织密度影,常累及下鼻道、下鼻甲;并伴有鼻中隔前份粘膜对称性增厚;结论：原发于鼻腔鼻窦     

Magnetic resonance imaging of the paranasal sinuses: incidental abnormalities and their relationship to patient symptoms.

OBJECTIVES: Magnetic resonance imaging (MRI) is able to demonstrate a wide range of abnormalities in the paranasal sinuses, which are often reported as incidental findings on scans performed for indications other than the evaluation of paranasal sinus pathology. However, the clinical significance of these findings remains undefined. We present a prospective study that determines the prevalence of abnormalities in the paranasal sinuses in a population undergoing MRI scans for suspected intracranial disease. These findings are correlated with clinical data pertaining to nasal and sinus symptoms. STUDY DESIGN: Prospective, cross-sectional study. METHODS: Patients undergoing MRI scans for suspected intracranial pathology were asked to complete a questionnaire pertaining to symptoms of nasal/sinus pathology. The T2-weighted scans of 86 patients (mean age = 51 years) were then reviewed for evidence of paranasal sinus pathology using a standardized method for evaluation and reporting of results. These results were then correlated with those obtained from the patient questionnaire. RESULTS: Radiologic abnormalities were found in the paranasal sinuses of 33 (38%) patients. Abnormalities were most commonly seen in the ethmoid sinuses (44.8%) followed by the maxillary (38%), sphenoid (14%), and frontal (3%) sinuses. Analysis of the clinical data revealed no significant relationship between the presence of clinical symptoms of nasal and sinus pathology and abnormalities on MRI scan. CONCLUSION: The assessment of inflammatory sinus pathology remains controversial. Based on the results of this study, incidental abnormalities of the paranasal sinuses detected on MRI scan do not appear to be related to clinical symptoms.     

The effect of physical work on the mucosal blood flow and gas exchange in the human maxillary sinus

The paranasal sinuses are lined with respiratory mucosa of principally the same structure as in the nasal mucosa but somewhat thinner. This mucosa has a rich blood flow and advanced system of blood vessels regulated mostly by the autonomous nervous system but also by other factors as acid/base balance and endocrine activity. The thickness of the nasal mucosa regulates the nasal breathing resistance and varies with among other factors, body activity. In this investigation we have studied the effect of physical work on the human maxillary sinus mucosa. The investigation shows that, as in the nose, the blood flow and the pulse amplitude are considerably reduced during physical work, in situations of heavy work falling to about half of the normal level, and probably result in the redistribution of blood from the respiratory mucosa. The gas exchange in the paranasal sinus is reduced only to a small extent, the reduction being too small to change the antral gas composition towards pathological conditions.     

Sphenochoanal polyp: diagnose and treatment

Choanal polyps (CP) are benign mucous tumours that usually originate in the mucosa of the maxillary sinus, and hence are termed antrochoanal polyps. CP rarely originates in the mucosa of other nasal structures and paranasal sinuses. The purpose of this brief clinical communication is to present six cases of CP originating in the sphenoidal sinus and termed sphenochoanal polyps (SCP).     

Mixed nasal mucus as a model for sinus mucin gene expression studies

OBJECTIVE/HYPOTHESIS: It is necessary to obtain sinus mucus from the paranasal sinus cavities to study mucin gene expression occurring in the sinuses during chronic sinusitis. This requires an invasive procedure to access the sinus cavity. There are embryological as well as histological similarities between nasal and sinus epithelia; therefore, we postulated that the mucin expression in the secreted nasal and sinus mucins might be similar. Nasal mucus, which can be obtained easily, could then replace sinus mucus in these studies. STUDY DESIGN: Sinus and nasal mucus from six patients with chronic sinusitis were analyzed in this study. METHODS: High-molecular-weight glycoproteins (mucins) were isolated and purified by sequential density gradient centrifugation in caesium chloride (CsCl). Enzyme-linked immunosorbent assay was performed to identify the antigenic identity of these mucins. RESULTS: The MUC2, MUC5AC, and MUC5B mucin genes were all expressed in the nasal and sinus mucus secretions. Antigenic studies showed an inverse relationship between MUC2 and MUC5AC expression in nasal and sinus mucus secretions. The MUC5B gene was the major mucin gene expressed in sinus mucus but not in nasal mucus. Expression of MUC2 was significantly higher in sinus mucus. Expression of MUC5AC was different between nasal and sinus mucus. CONCLUSIONS: Individual mucin expression in sinus and nasal mucus was markedly different. From this preliminary study, we conclude that nasal mucus is not a suitable substitute for sinus mucus in sinus mucin gene studies and that different pathological processes are taking place in nasal and sinus tissue in chronic sinusitis.     

Hypoxia stimulates inflammatory and fibrotic responses from nasal-polyp derived fibroblasts

OBJECTIVES/HYPOTHESIS: Chronic sinusitis is primarily an inflammatory disorder characterized by hyperplasia of immune cells and sinus tissue. Nasal mucosal swelling or polyps can occlude the sinus ostia, decreasing the level of oxygen available to the sinus tissue. Hypoxia in many diseases results in increased recruitment of inflammatory cells and release of cytokines. The role of hypoxia in chronic sinusitis is unknown. We hypothesized that hypoxia induces production of mediators that recruit cells into the sinus tissue and are involved in remodeling of the nasal mucosa. METHODS: We compared data from unstimulated nasal-polyp derived fibroblasts with those cultured in hypoxic (10% O2) and anoxic (0% O2) environments. Changes in mRNA expression and protein levels of cytokines and chemokines were measured along with changes in cellular proliferation. RESULTS: Hypoxic conditions did not change the proliferative capacity of fibroblasts, whereas anoxia led to a 40% reduction in cellular proliferation (P < .05). Hypoxia led to increases in secretion of many cytokines including vascular endothelial growth factor and CCL11. As a marker of remodeling, procollagen and fibronectin production were significantly increased under hypoxic conditions. CONCLUSIONS: Hypoxic conditions present in the sinus tissue could increase production of proinflammatory and remodeling cytokines that contribute to the inflammation observed in sinusitis. Surgical intervention may help decrease inflammation by allowing reoxygenation of the sinus cavity and decrease the hypoxic induction of cytokines and remodeling factors.     

Retention fluids of chronic sinusitis induce neutrophil adherence to microvascular endothelial cells.

The adherence of circulating leukocytes to the vascular endothelium is a critical step in the emigration of leukocytes through blood vessel walls to inflammatory lesions. The influence of nasal secretions on the adherence of neutrophils to the vascular endothelium was investigated using monolayers of human mucosal microvascular endothelial cells derived from the inferior turbinate. Preincubation of vascular endothelial cells with retention fluids from the maxillary sinus of the patients with chronic sinusitis showed increased neutrophil adherence. Recombinant IL-1 beta was also tested and found to induce adherence of neutrophils to human mucosal microvascular endothelial cells. However, no adhesive effect was observed with the nasal secretions of nasal allergy. An enzyme-linked immunosorbent assay detected considerable amounts of IL-1 beta in the chronic sinusitis retention fluids, while the amounts of IL-1 alpha and TNF-alpha were very low. The increased adhesion of the neutrophils by the retention fluids of chronic sinusitis was also neutralized by the incubation with anti-IL-1 beta antibody in a dose dependent manner. These findings suggest that IL-1 beta in the paranasal secretion of chronic sinusitis induces the adherence of neutrophils to vascular endothelium and subsequent infiltration of neutrophils in the paranasal sinuses, thus contributing to the persistence of chronic sinusitis.     

Matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 gene expressions and their differential regulation by proinflammatory cytokines and prostaglandin in nasal polyp fibroblasts.

Chronic inflammation of the paranasal sinus leads to nasal polyp (NP) formation. In this study, we investigated the effect of stimulation of the proinflammatory cytokines interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha) and prostaglandin (PG) E2 on the production of messenger RNA (mRNA) of matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-I (TIMP-1) in nasal polyp fibroblasts (NPFs) and nasal mucosa fibroblasts (NFs). The mRNAs of IL-1alpha, TNF-alpha, MMP-1, and TIMP-1 in 40 surgical specimens of NPs were studied by in situ hybridization to corroborate the in vitro findings. The results indicated a significant amount of constitutive MMP-1 mRNA in NPFs and cytokine-induced MMP-1 steady-state mRNAs in NFs. The effect of stimulation of cytokines on TIMP-1 mRNA synthesis was unremarkable in NPFs and NFs. Exogenous PGE2 enhanced cytokine-stimulated MMP-1 mRNA synthesis in NPFs. In situ hybridization revealed that cells expressing MMP-1 and TIMP-1 mRNAs (primarily plasma cells, fibroblasts, and endothelial cells) gathered around areas with loose stroma, suggestive of rapid extracellular matrix degradation. These data suggest that the pathogenesis of nasal polyposis could be related to production of MMP-1 and consequent promotion of matrix collagenolysis.     

Ventilation and drug delivery to the paranasal sinuses: studies in a nasal cast using pulsating airflow

BACKGROUND: Although there is a high incidence of nasal disorders including chronic sinusitis, there is limited success in the topical drug delivery to the nose and the paranasal sinuses. This is caused by the nose being an efficient filter for inhaled aerosol particles and the paranasal sinuses being virtually non ventilated METHOD: The objective of this study was to visualize the efficiency of sinus ventilation in a nasal cast using dynamic 81mKr-gas imaging in combination with pulsating airflows. Furthermore, the efficiency of the deposition of radiolabelled aerosol was assessed. RESULTS: Pulsation increased ventilation efficiency of the sinuses more than fivefold and aerosol deposition efficiency more than twentyfold, compared to delivery without pulsation. Furthermore pulsation increased aerosol deposition in the nasal airways by a factor of three. Using pulsating airflow Kr-gas ventilation and aerosol deposition efficiencies increased with increasing sinus volume. Pulsating airflow resulted in a deposition of up to 8% of the nebulized drug within the sinuses compared to 0.2% without pulsation. CONCLUSIONS: The study demonstrates the high efficiency of a pulsating airflow in paranasal sinus ventilation and aerosolized drug delivery. This proves that topical drug delivery to the paranasal sinuses in relevant quantities is possible.     

Secretory IgA and serum type IgA in nasal secretion and antibody activity against the M protein

We studied IgA immunoglobulins in nasal secretions in order to clarify mucosal immunity of the nasal cavity and paranasal sinuses during chronic nasal infection. Secretory IgA and serum type IgA of 165 samples of nasal secretions were analyzed quantitatively by use of electroimmunodiffusion techniques, and the specific antibody activity of secretory IgA against the M protein of Streptococcus pyogenes was investigated by use of enzyme-linked immunosorbent assay. Results show that although the secretory IgA content in nasal secretions was elevated in chronic sinusitis, its specific antibody activity against the M protein was lower than that in normal subjects. This evidence suggests that nonspecific secretory IgA antibodies are predominantly produced in chronic sinusitis, and that mucosal immunity preventing the adherence of bacteria is impaired in the diseased mucosa.     

Acoustic rhinometry in healthy humans: accuracy of area estimates and ability to quantify certain anatomic structures in the nasal cavity

OBJECTIVES: We evaluated the accuracy of acoustic rhinometry (AR) measurements in healthy humans and assessed the ability of AR in quantifying the dimensions of the paranasal sinuses and certain anatomic structures in the nasal cavity. METHODS: Twenty nasal passages of 10 healthy adults were examined by AR and computed tomography (CT) before and after decongestion. Actual cross-sectional areas of the nasal cavity and actual locations of the nasal valve, the head of the inferior turbinate, the head of the middle turbinate, the ostia of the frontal and maxillary sinuses, and the choana were determined from CT sections perpendicular to the curved acoustic axis of the nasal passage. RESULTS: The AR-measured cross-sectional areas in the anterior nasal cavity were in reasonable agreement with the corresponding areas determined from CT, whereas AR consistently overestimated the passage areas at locations posterior to the paranasal sinus ostia. The nasal valve was identified as a pronounced minimum on the AR area-distance curve. However, AR did not discretely identify the head of the inferior turbinate, the head of the middle turbinate, or the choana. CONCLUSIONS: The local minima on the AR area-distance curve beyond the nasal valve are caused by acoustic resonances in the nasal cavity, and do not correspond to any anatomic structure. The AR area overestimation beyond the paranasal sinus ostia is due to the interaction between the nasal cavity and the paranasal sinuses, rather than to sound loss into the sinuses. Acoustic rhinometry provides no quantitative information on ostium size or sinus volume in either non-decongested or decongested nasal cavities.     

Bacteria in chronic maxillary sinusitis.

Sixty-one chronically inflamed maxillary sinuses produced 131 bacterial strains from mucosal pieces that were taken during a Caldwell-Luc operation and cultured aerobically and anaerobically. Sinus secretions showed only 62 and nasal secretions 106 bacterial strains. Fourteen mucosal strains, including 11 Haemophilus influenzae, grew heavily. None of 24 mucosal anaerobes showed heavy growth. Of 52 antral mucosae with culturable bacteria, 37 disclosed mixed and 15 pure growth. The bacteriological characteristics of the diseased sinus and the nose did not correlate. The duration or extent of the disease, the macroscopic appearance of the diseased sinus, or the presence or absence of allergy were unrelated to bacteriological findings, except that H influenzae was concentrated in purulent sinuses. Intraoperative culture of antral mucosa seems to give the most reliable picture of the bacteriological condition in chronic maxillary sinusitis.