[Georgia, a country of diverse aid from Germany in the ENT field]. / Georgien, ein Land vielfältiger Hilfen aus Deutschland auf dem HNO-Gebiet.

Following a long-term tradition, several teams of German ENT specialists are currently working in different Georgian clinics on a charitable basis. The current paper describes the structures of the medical and health insurance systems in this southern Caucasian country. The course of medical education for physicians in Georgia is portrayed and differences to the German situation which explain why young Georgian colleagues have difficulties when moving to Germany are highlighted. The paper describes the typical stay of a German ENT specialist in Georgia and also points out how these physicians are in turn supported in their charitable work by medical devices and equipment sent from Germany. Finally, the input that German colleagues can contribute to improving the situation in the Georgian health care system is discussed from the perspective of German ENT specialists and future goals of the cooperation between German and Georgian physicians are summarized.

[Three-dimensional analysis of nasal physiology : Representation by means of computational fluid dynamics]. / Dreidimensionale Analyse nasaler Physiologie : Darstellung mit numerischen Simulationen.

The human nose takes primary responsibility for preconditioning inhaled air. Numerous pathologies can affect the physiology of the nose. The beginnings of flow analyzes were carried out with three-dimensional casting models and differently colored liquids. Temperature and humidity could not be taken into account. Today, much more complex analyzes are possible using computational fluid dynamics (CFD), which are based on three-dimensional models generated from computed tomography (CT) or magnetic resonance imaging (MRI) datasets. Here, flow velocities, temperature, humidity, and pressure differences can be simulated and displayed in high-resolution videos as a function of multiple boundary conditions. The analysis of pathological changes or surgical interventions is thereby possible.

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.

Physiologic and pathologic septal deviations: subjective and objective functional rhinologic findings.

OBJECTIVE: A high incidence of septal deviation with significant inter-rater variability has been reported. An explanation could be the presence of physiological septal deviation besides pathological ones. We differentiated an unselected cohort by their nasal resistance into groups with physiological normal and pathologically increased resistance to detect differences and analogies in comparison to healthy subjects and a pathological cohort. STUDY DESIGN: Prospective cohort study. SETTING: A total of 356 patients were assessed using rhinoresistometry, acoustic rhinometry, endoscopy and visual analogue scales. After definition of a benchmark between physiological and pathological nasal resistance, group differences were calculated and correlations analysed. RESULTS: The normal one-sided inspiratory nasal resistance was defined as less or equal to 0.35 sPa/cm^3 at a flow-velocity of 250 cm^3/s (R250). Using this benchmark, the unselected group of non-rhinological patients was differentiated into 114 subjects with physiological nasal resistance and 44 with pathological septal deviation. Nasal resistance after decongestion was significantly lower for normal or patients with a physiological septal deviation in comparison to the rhinological one on both nasal sides. Healthy subjects and patients with physiological septal deviation showed similarities in objective rhinological parameters as well as rhinological patients and patients with pathological septal deviation derived from the unselected group of non-rhinological patients. Furthermore, this benchmark of nasal resistance shows significant correlations with subjective assessment of nasal breathing. CONCLUSION: Inspiratory nasal resistance obtained at a flow-velocity of 250 cm^3/s using rhinoresistometry may be useful to distinguish patients with physiological and pathological septal deviation. Correlation with subjective assessment and endoscopic findings is improved.

[Diagnostic methods of nasal respiratory function]. / Diagnostik der respiratorischen Funktion der Nase.

Objective assessment of nasal obstruction may help with preoperative planning for rhinosurgery and indicate different aspects of endonasal pathology. To improve quality control, preoperative and postoperative objective assessment is desirable. This review presents objective functional diagnostic tools and explains their appropriate uses, the information obtained, and their limitations. An algorithm is presented for analysing nasal obstruction by means of objective functional assessment. Examples illustrate how to use this information for preoperative planning in rhinosurgery.

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 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.

Rhinosurgical therapy planning via endonasal airflow simulation.

Nowadays, Computational Fluid Dynamics (CFD) methods play an important part in the production process of the automotive industry. Progress in recent years has made possible highly sophisticated airflow-simulation models that are used in engineering for optimization and verification of aerodynamics. The key purpose of the Simulation Tool for Airflow in the human Nose (STAN), developed at the Darmstadt University of Technology in cooperation with the University Hospital in Greifswald, is to use these techniques to support the rhinosurgeon in diagnosis and planning of therapy (Frühauf T, Mlynski G. Simulation and visualization of the air flow in the human nose. Proceedings of the First World Congress on Computational Medicine, Austin, Texas, 1994). A system has been developed that realizes a three-dimensional (3D) reconstruction of the endonasal cavities based on computer tomography (CT) scans. This semiautomatic reconstruction method requires minimal manual intervention. The surface model is used to create an unstructured 3D volume mesh suitable for finite volume simulations. In this way, an individual simulation based on patient-specific data can be realized. At the University Hospital in Greifswald, experimental investigations and measurements are made in nasal models to verify the simulation result. The goal of this project is to investigate individual nasal complaints and to detect respiratory disorders. The surgeon should be able to simulate the disordered respiration before performing a surgical procedure, and thereby increase the effectiveness of surgical planning.

Videoendoscopic analysis of nasal steroid distribution.

Topical corticosteroids are one of the main pillars in the treatment of nasal polyps. The exact topography of their intranasal deposition has not yet been adequately visualised. The intranasal distribution of a 1% sodium fluorescein solution applied with original Pulmicort Topinasal (budesonide) metered pump bottles was analysed by videoendoscopy. The study group included eight healthy subjects and ten patients who had undergone endonasal sinus surgery. Videoendoscopy was performed in the study group within the first minute after application of the fluorescein solution. Additionally the deposition pattern of Pulmicort Topinasal was analyzed using a nasal model. The examination showed that the majority of the substance is deposited on the anterior portion of the nasal septum and the head of the inferior turbinate. Only a small fraction actually reaches the middle meatus. The distribution is improved by application during the decongested phase of the nasal cycle, after use of vasoconstricting nasal drops and maintaining a spraying angle of 45 degrees upwards. The development of new delivery techniques and systems could improve the efficacy of intranasally administered corticosteroids and reduce the complication rate.

The influence of the muscles of facial expression on the development of the midface and the nose in cleft lip and palate patients. A reflection of functional anatomy, facial esthetics and physiology of the nose.

The further improvement of well-established techniques in primary and secondary cleft surgery requires a detailed and interdisciplinary knowledge and observation of anatomical, functional and developmental problems. An investigation into the macroscopic and microscopic anatomy of the perinasal and perioral muscles and parts of the human nasal septum, as well as into the pathomorphology of ancient skulls with untreated clefts is presented. On this basis an interpretation of clinical findings in untreated newborns compared with surgically treated CLP-patients has been undertaken. The 3D-CT, superimposing photography and coloured experimental settings of nasal airflow complete the visualisation of the anatomical and functional findings.