Comparative investigations of anatomy and physiology in mammalian noses (Homo sapiens--Artiodactyla).

BACKGROUND: Knowledge of airflow in animal noses is sparse. Such knowledge could be important for selection of animal models used in environmental studies. From the phylogenetic and ontogenetic point of view, a comparison between the animal and human nose is interesting. METHOD: Nose models of 5 even-toed ungulate species (he-goat, sheep, cow, roebuck, wild boar) and two humans (new born infant and adult) were examined. Anatomical and physiological features of the nasal cavities of all species were compared. All models were rinsed with water and the flow was visualized for observation. Geometric and rhinoresistometric measurements were then performed. RESULTS AND CONCLUSIONS: Even-toed ungulates have two turbinates directly in the main part of the nasal airflow (respiratory turbinates) and a different number of turbinates in a so-called dead space of the nasal airflow above the nasopharyngeal duct (ethmoidal turbinates). The latter correspond with the upper and middle turbinate in analogy to the human nose. Respiratory turbinates of even-toed ungulates insert immediately behind the external nasal ostium. Thus, the whole nasal cavity acts as a functional area with the exception of a small area acting as dead space only detectable in ruminants, possibly indicating a small evolutionary progress from suinae to bovidae. The shape of the animal nasal cavity is stretched and flat. The airflow runs nearly completely turbulent through the nose. The nasal cavity in the adult human is relatively short and high. The area between the external nasal ostium and the head of the inferior turbinate is called inflow area. It distributes the airflow over the whole nasal cross section and generates a turbulent flow. So the airflow is prepared to contact the mucosa in the functional area (turbinate area). The morphology of the inflow area is approximately formed by the shape of the external nose. The nasal cavity of a newborn child is also stretched and flat and more similar to the nasal shape of the investigated animals. The inflow area in the newborn nose is not yet developed and corresponds with the growing external newborn nose. One can hypothesize that the inflow area in human noses is a morphological adaptation in the changed length-height-ratio of the nasal cavity.

[Observations on the anatomy and physiology of the mammalian noses]. / Betrachtungen zur Anatomie und Physiologie von Säugetiernasen.

From the anatomical and flow dynamic point of view, the mammalian noses are strictly divided in a respiratory and olfactory area. In humans, the middle and the superior turbinate (ethmoturbinates) fulfill the respiratory and olfactory function. An intensive contact between breathing air and respiratory mucosa is the most important pre-condition for the respiratory function of the nose. In all investigated species this contact takes place in the functional area of the nose, i. e. the area of the turbinates. In humans, the area from the external nasal ostium up to the head of the inferior turbinate is called "inflow area". This part of the nose distributes the airflow over the complete nasal cross sectional area and generates turbulent flow. The inflow area in the human nose is an adaptation to the relatively increased nasal height during evolution.

First findings concerning airflow in noses with septal deviation and compensatory turbinate hypertrophy--a model study.

BACKGROUND: The nasal septal deviation is a common cause of nasal obstruction. On the other hand, many septal deviations are asymptomatic. It seems a physiological adaptation occurs on both sides. Septal deviation leads to internal nasal asymmetry, which in turn causes compensatory change in turbinate morphology (e.g. turbinate hypertrophy respectively hypotrophy). This mechanism is investigated with the help of fluid dynamic experiments and functional rhinologic diagnostics. METHODS: Functional models of the nose (modified Mink's boxes) were used and assessment was made by acoustic rhinometry and rhinoresistometry, followed by flow dynamic investigations. Septal deviations of varying position, together with turbinates of differing grades of hypertrophy, were simulated and assessed. RESULTS AND CONCLUSIONS: We observed in models of septal deviation an increase in flow resistance on the ipsilateral side as a result of friction of flow particles in the narrowing. Furthermore, on the opposite side of the deviation, the enlargement of the stream channel did not generally lead to a reduction in flow resistance, but rather to a 'dead space', where only a slow-circling eddy was observed. This eddy causes an increase in turbulence. In vivo turbinate hypertrophy occurs to fill this dead space, thereby reducing turbulent flow without a significant increase in resistance. In cases of moderate septal deviation, compensatory mechanisms of the turbinates can lead to a normalization of nasal airflow and surgical therapy would not be indicated. Deviations in the anterior part of the septum seem to be more symptomatic, because the mechanism is missing and due to the physiological narrowing of the nasal isthmus. To differ between physiologic and pathologic deviation, functional diagnostics are needed.

Investigations for the diagnostic recording of nasal wing collapse.

BACKGROUND: The inspiratory medial movement of the nasal wing at high flow velocities is a protective physiologic mechanism. If this collapse of the nasal wing occurs at lower flow velocities, it may result in nasal obstruction. "Nasal wing collapse" is generally a clinical diagnosis. However, in the pressure-flow relationship of rhinomanometry, the medial movement of the nasal wing can be documented in the inspiratory arm of the graph. The diagnostic impact of this hysteresis was investigated. METHODS: The pressure-flow curves of three box models and three nasal models with a moveable valve (analogous to the nasal wing) in the entrance area as well as three volunteers with unstable nasal wings were investigated. We recorded synchronously the pressure-flow relationship and by endoscopy the movement of the valve in the box models and the nasal wing in the volunteers on video. For evaluation, we used the frame by frame analysis of the tape. RESULTS AND CONCLUSIONS: The medial movement of the nasal wing causes a hysteresis in the inspiratory arm of the pressure-flow curve. At this point, the graph runs on or between two border curves, termed the "no collapse curve" (for the maximally opened valve or a stable nasal wing) and the "collapse curve" (for the subtotally closed valve or a collapsed nasal wing), respectively. Analogous to the nasal wing motion, the descending course of hysteresis runs in two phases, and the ascending course runs in three phases. The medial movement of the nasal wing is expressed by a deviation of the graph from the "no collapse curve." The flow, at which the graph leaves this curve, depends on the elasticity module of the nasal wing. The extent of nasal wing collapse is reflected by the approximation of the pressure-flow curve to the "collapse curve" of the graph. The hysteresis appears because of a late opening of the collapsed nasal wing.

[The use of the platysma myocutaneous flap for reconstruction in the head-neck area -- a retrospective study]. / Der Einsatz des myokutanen Platysmalappens im Kopf-Hals-Bereich -- Eine retrospektive Studie.

OBJECTIVE: Following extended tumor resections in the head-neck area options immediate defect reconstruction is needed to reduce healing time and improve rehabilitation. Reconstruction of significant areas of mucosal defects is best accomplished by introduction of a pliable regional transplant. The platysma myocutaneous flap has been used for defect reconstruction in head and neck area since more than 20 years. Its popularity is limited. Since 2001 in our department the platysma mucocutaneous flap is used for such reconstructions. We present a retrospective study evaluating our experience with the platysma myocutaneous flap. METHOD: From 2001-2003 25 patients have been subjected to surgical reconstruction applying the platysma mucocutaneous flap. The primary tumor was located in 16 patients (64 %) in the oropharynx, in 5 patients (20 %) in the hypopharynx and in 4 patients (16 %) in the oral cavity. Evaluation was based on medical records including the operative reports. All patients get a follow up in our outpatient clinic. RESULTS: The platysma flap is easy to harvest and has a low general risk level. Complications are minor and may be avoided by exact preoperative planning. Necrosis of the skin-muscle-flap was observed only after resection of the A. carotis externa (two cases). In these 2 cases an operative revision was necessary (stenting of the pharynx or secondary reconstruction by pectoralis major-flap). The resection of the A. facialis (three cases) did not lead to a serious complication. CONCLUSIONS: Considering the exact indication the platysma flap is suitable for reconstruction of surface defects in the pharynx and oral cavity. A special attention is given to the ipsilateral vascular supply and the length of the muscular pedicel. It proved to be a cost effective method due to the less time and personal expenditure.

The nasal airflow in noses with septal perforation: a model study.

BACKGROUND: Septal perforation is a common clinical problem in rhinology. Affected patients suffer from a dry nose, crusts as well as recurrent epistaxis and sometimes an inspiratory whistle. The aim of this study was to investigate the underlying flow dynamic mechanisms. METHODS: The physical flow effects of such pathologies were examined in functional nose models (box models) and anatomically exact models of the nose. Therefore, septal perforations of different sizes and localisations were studied in straight and deviated nasal septa. RESULTS AND CONCLUSIONS: It could be seen that the localisation of the perforation has no impact on the flow pattern. In large septal perforations, the air jet collides with the posterior edge of the perforation and disintegrates turbulently. Since airflow is physiologically turbulent in the posterior part of the nose, posterior perforations do not cause clinical complaints. The inspiratory whistling sound during respiration is based on the principle of a lip whistle. Large perforations do not cause a whistling sound. The necessary high flow velocity needed in large perforations is usually not achievable.

Investigations of the influence of external nose deformities on nasal airflow.

BACKGROUND: Abnormalities of the external shape of the nose are often felt as cosmetically disturbing. In many cases an additional hampering of the respiratory function of the nose is seen and causes pathological nasal airflow patterns. For the functional outcome of aesthetic-surgery of the nose, knowledge of nasal flow is essential. In the medical literature there are some discrepancies between the relationship of nasal shape and nasal flow. We investigated typical airflow patterns in different abnormalities of the external nose. METHODS: We performed fluid dynamic experiments on exact, anatomical nasal models and functional nasal models (so-called modified Mink boxes). We investigated the inspiratory flow pattern in nose-models with typical variations of the shape of the external nose. RESULTS AND CONCLUSIONS: There were typical airflow patterns for every external nasal abnormalities. The normal nose shows a disturbance of the streamlines over the entire nasal cavum. Under physiological flow velocities we find laminar and turbulent flow. The pathological variations of the nasal shape show mostly different airflow patterns and characteristics. The main reason for that is a deformed or anatomically false configurated inflow area (vestibulum, isthmus and anterior cavum). During rhinoplasty the reconstruction of the nasal inflow area has to be taken into account.

[Objectivation of nasal swelling--a comparison of four methods]. / Die Objektivierung des Schwellungszustandes der Nasenschleimhaut--ein Vergleich von vier Messmethoden.

BACKGROUND: The measurement of the nasal swelling is very common in rhinologic diagnostics. For that, there are different methods available. Especially the nasal provocation test is important in this relationship. The measurement of the obstruction, caused by swelling of the nasal erectile tissue, allows a quantification of the allergic reaction. METHOD: We tested four different methods for objectivation of the mucosal swelling, which are used in the routine clinical examination: 1. acoustic rhinometry, 2. rhinoresistometry, 3. expiratory peak-flow-metry and 4. rhinomanometry. 40 volunteers were examined with the four methods before and after decongestion of the nose. We compared the results of each method (1. - 3.) with the results obtained by rhinomanometry. RESULTS: We found only a good correlation between rhinomanometry and rhinoresistometry. Both methods seem to be suited for the objectivation of nasal swelling.

The combination of acoustic rhinometry, rhinoresistometry and flow simulation in noses before and after turbinate surgery: a model study.

BACKGROUND: Especially to young examiners, the interpretation of rhinometric findings seems to be difficult. In order to understand rhinometric assessments precisely, knowledge of airflow behavior in the nose is necessary. We therefore investigated the influence of nasal concha surgery on acoustic rhinometry and rhinoresistometry in a model. METHOD: Six nose models were examined with acoustic rhinometry and rhinoresistometry, each of these models with its lateral wall altered to represent various conditions after nasal concha surgery. Besides, all models were rinsed with water and the flow was visualized for observation. RESULTS AND CONCLUSIONS: The normal nose presented an even flow distribution over the entire nasal cavity. After nasal concha resection, though, an unfavorable flow course and a strong increase in turbulence were seen. Additionally, flow resistance decreased considerably. In the model with general lateral wall hyperplasia, reduction of the inferior and even of the middle nasal concha showed good functional results. The model revealed a good correlation between the result of flow observation and findings in acoustic rhinometry and rhinoresistometry. Both methods complement one another in their diagnostic outcome.

[Fibrolipoma of the larynx]. / Fibrolipom des Larynx.

Benign mesenchymal tumors of the upper aerodigestive tract are very rare. In this localisation some tumors cause life-threatening upper airway obstruction. We report on a 42-year old man who complained dysphagia and globus sensation. The physical examination revealed a smooth tumor of the left aryepiglottic fold. A magnet resonance imaging (MRI) leaded to the suspicion of a laryngocele with extension in the left aryepiglottic fold. The therapeutical procedure included the microlaryngoscopical extirpation of the tumor with laser surgery. The histology showed a fibrolipoma of the larynx. Because of frequent recurrences even after an extended period of time long term follow-up is necessary.

[First findings about the nasal airflow in noses with septal perforation]. / Erste Erkenntnisse über die nasale Atemströmung bei Septumperforationen.

BACKGROUND: A nasal septum perforation often leads to considerable complaints like nasal obstruction, crusting, epistaxis or whistling. Up to now there is no certain knowledge about the airflow pattern in noses with septal perforations. METHOD: We performed fluid dynamic experiments on functional nasal models (so-called modified Mink boxes). We investigated the flow pattern in models with septal perforations, different in size and location and in combination with and without septal deviations. RESULTS AND CONCLUSIONS: We have found no essential influence of the location of perforation on the airflow pattern. With increasing size of perforation the streamlines bump toward the posterior border of the perforation, causing turbulence. The whistling during inspiration is based on the principle of a lip whistle. The required flow velocity for vibration of the air depends on the dimension of the perforation. For large perforations it is impossible to get the required high flow velocity to cause a whistle.

[Interesting case no. 44. Osteoma]. / Der interessante Fall Nr. 44. Osteom.

We report on a 30-year-old man who was treated in the outpatient clinic for bifrontal headache for four weeks. Computed tomography showed sinusitis maxillaris, a large osteoma in the ethmoid sinus on the right side and a pneumocephalus. The surgical procedure included removal of the focus (sinusitis), extirpation of the osteoma and reconstruction of the skull base from an external approach.

Correlation of nasal morphology and respiratory function.

In order to investigate the fluid dynamic preconditions that guarantee a sufficient contact of air with nasal mucosa, we studied flow patterns in modified "Mink's boxes" and in nasal models. As a result, the nose can be divided into 1) a functional area, i.e. area of turbinates, 2) an inflow area, i.e. vestibulum, isthmus and anterior cavum and 3) an outflow area, i.e. posterior cavum, choanae and epipharynx. The vestibulum is shaped like and acts as a bend, redirecting air to the cavum, and as a nozzle, reducing turbulence. With its concavely curved shape, the isthmus facilitates equal distribution of air throughout the entire area of the turbinates. The anterior cavum acts as a diffuser, where turbulence increases and velocity decreases. In the slit-like space of the area of turbinates, the flow behavior is determined by flow dynamics in the inflow area. The structure elements of the outflow area are similar to those of the inflow area but lined up in an inverse order.

[Model studies of nasal turbinate surgery]. / Modelluntersuchungen zur Nasenmuschelchirurgie.

The improvement of nasal air flow often requires, in addition to septoplasty, surgery of the turbinates. In order to broaden our knowledge of the influence of turbinate surgery on nasal function, the authors investigated nasal models with different lateral walls by visualisation of flow patterns and rhinoresistometry. Anterior turbinoplasty and turbinectomy reduce the nasal resistance to air flow, but the respiratory function of the nose deteriorates. As the result of these experiments, a trimming of hyperplastic turbinates must create a normal shape of lateral nasal wall, because the respiratory function is based on nearly regular narrow cavities.