[Video head impulse test or caloric irrigation?. Contemporary diagnostic tests for vestibular schwannoma]. / Video-Kopfimpulstest oder thermische Prüfung? Zeitgemäße Funktionsdiagnostik des Vestibularisschwannoms.

The video head impulse test (vHIT) is a new method for investigating vestibular function that is currently poorly studied in terms of its value for clinical diagnosis in otolaryngology. Both the caloric irrigation and vHIT serve to evaluate the horizontal vestibulo-ocular reflex. In the present study, caloric irrigation and vHIT were compared in 46 patients with vestibular schwannoma. Caloric irrigation exhibits a higher sensitivity than vHIT (72% versus 41%) and both tests show only a moderate correlation. Tumor size and hearing level was significantly correlated with caloric abnormalities but not with vHIT findings. Since caloric irrigation and vHIT measure the hVOR in low and high frequency ranges, respectively, these tests have to be considered complementary and are valuable in both diagnostics and therapeutic decisions.

[The EXIT procedure]. / Ex-utero-intrapartum-treatment-Manöver.

The ex utero intrapartum treatment (EXIT) procedure is used for unborn fetuses in cases of predictable complications of postpartum airway obstruction. Indications for the EXIT procedure are fetal neck tumors, obstruction of the trachea, hiatus hernia of the diaphragm and congenital high airway obstruction syndrome (CHAOS). Large cervical tumors prevent normal delivery of a fetus due to reclination of the head with airway obstruction. Therefore, a primary caesarean section or the EXIT procedure has to be considered. The EXIT procedure has time limitations as the blood supply by the placenta only lasts for 30-60 min. Airway protection has to be ensured during parturition.This article reports the case of an unborn fetus with a large cervical teratoma where an obstruction of the cervical airway was detected and monitored by ultrasound and magnetic resonance imaging (MRI) during pregnancy. The EXIT procedure was therefore used and successfully accomplished. The features of the interdisciplinary aspects of the EXIT procedure are described with the special aspects of each medical discipline.

[The video head impulse test: first clinical experiences]. / Der Video-Kopfimpulstest: Erste klinische Erfahrungen.

BACKGROUND: Side-specific test procedures are mandatory in order to assess the function of peripheral vestibular receptors. Semicircular canals (SCC) and vestibulo-ocular reflex (VOR) can be tested by the Halmagyi and Curthoy head impulse test (HIT) and recently by means of the video head impulse test (vHIT). The vHIT procedure is a new method to measure eye and head velocity during brief and rapid head impulses. This method provides objective information of VOR and detects both overt and covert catch-up saccades. MATERIALS AND METHODS: As clinical experiences with vHIT are limited, in this study the horizontal VOR (hVOR) was examined by means of the vHIT in 142 consecutive patients with acute or chronic vestibular syndrome. RESULTS: A total of 20 healthy volunteers served as a control group and exhibited a normal average VOR gain of 0.97 ± 0.09 without re-fixation saccades. In patients, 47.6% showed a pathological vHIT whereas 52.4% revealed a normal test result. Covert catch-up saccades could be revealed in 13.7% by means of vHIT whereas in 86.3% overt catch-up saccades alone or in combination with covert catch-up saccades were found in the majority of catch-up saccades in peripheral vestibular disorders. CONCLUSIONS: By means of the vHIT it is possible to obtain a side-specific and quantitative assessment of hVOR. Video-head impulse test is a reliable tool for vestibular testing even in bedside examinations of patients suffering from dizziness.

Dynamic Change of VOR and Otolith Function in Intratympanic Gentamicin Treatment for Ménière's Disease: Case Report and Review of the Literature.

Intratympanic gentamicin treatment (IGT) is an evidence-based therapeutic option for recurrent vertigo attacks in Ménière's disease (MD). Today, in MD it is possible to monitor changes of vestibular receptor function, induced by IGT, with objective test methods such as the video head impulse test (vHIT) and cervical and ocular vestibular evoked myogenic potentials (cVEMP, oVEMP) in a dynamic, time-and frequency-dependent manner. We report on a 65-year-old female patient with recurrent vertigo attacks in a right-sided MD, where receptor function was followed up before and up to 4 weeks after IGT (time dynamic). Quantitative changes of vestibular function (frequency dynamic) were detected with bithermal calorics and vHIT, with air-conducted sound (ACS) cVEMP and bone-conducted vibration (BCV) oVEMP at 500 Hz. The horizontal vestibuloocular reflex (hVOR) gain in vHIT decreased successively until the 4th week with the appearance of catch-up covert and catch-up overt refixation saccades, and side asymmetry increased in caloric testing. Saccular function was extinguished within 4 weeks, whereas utricular function was diminished after 4 weeks. Monitoring vestibular receptor function with objective test methods provides a quantitative insight into the dynamic activity of vestibular function and is therefore applicable in order to adjust IGT regimen at different therapeutic stages.

[Isolated functional loss of the lateral semicircular canal in vestibular neuritis]. / Isolierte Rezeptorfunktionsstörung des horizontalen Bogengangs.

Today, modern tools in vestibular testing are feasible to provide information about functional status of all five peripheral vestibular receptors. Isolated or combined loss of crista and macula receptor function can be determined in the diagnostic process. We describe a seldom case of isolated functional loss of lateral semicircular canal receptor function in a 55-year-old patient. Whereas there was no ispilateral caloric response and video head impulse test revealed a catch-up saccade, air-conducted (AC) cervical and ocular vestibular-evoked myogenic potentials (cVEMP, oVEMP), subjective visual vertical and MRI were normal.

[Receptor function of the semicircular canals. Part 2: pathophysiology, diseases, clinical findings and treatment aspects]. / Rezeptorfunktion der Bogengänge. Teil 2: Pathophysiologie, Erkrankungen, klinische Befunde und therapeutische Aspekte.

Perturbation of semicircular canal function may result in a pathological angular vestibulo-ocular reflex (aVOR). The resulting impairment in gaze stabilization is perceived as "vertigo" or "dizziness" and may occur following receptor function impairment of all three semicircular canals. The head impulse test reveals hidden (covert-catchup) or visible (overt-catchup) saccades in disturbances of semicircular function. Most peripheral vestibular disorders can be treated conservatively. There are surgical treatment options for some diseases, such as intractable benign paroxysmal positional vertigo and superior semicircular canal dehiscence. Vestibular training promotes central reorganization of the VOR. Impaired semicircular receptor function, in particular bilateral vestibulopathy, may affect spatial orientation and cognitive processes. Balance prostheses could serve as a replacement for receptors in the future.

[Receptor function of the semicircular canals: Part 1: anatomy, physiology, diagnosis and normal findings]. / Rezeptorfunktion der Bogengänge: Teil 1: Anatomie, Physiologie, Diagnostik und Normalbefunde.

The perception and conversion of motion stimuli by the vestibular receptors, unimpaired postural control and intact visual acuity are essential for spatial orientation. Disturbances in these three sensory systems can manifest as "vertigo", "dizziness" or "imbalance". The integrity of peripheral receptor function, especially of the three semicircular canals, plays a superficial role. They are sensitive to acceleration stimuli, which they transmit via reflexes to the eye muscles. The stabilization of a visual target is via vestibulo-ocular reflexes, which have a very short latency and thus ensure a permanently stable image on the retina. Modern lateral-specific testing procedures are available to diagnose the receptor function of the peripheral vestibular system. The function of the semicircular canals can be analyzed using a head impulse test (HIT) and, more recently, by means of video-HIT as well as on the basis of a caloric test. Using these techniques, all three semicircular canals can be assessed in a side- and receptor-specific manner.

[Aneurysmal bone cyst of the ethmoid sinus and skull base in a 3-year old child: a rare location of a benign bone lesion]. / Aneurysmatische Knochenzyste der Rhinobasis bei einem 3-jährigen Kind: Seltene Lokalisation einer benignen Knochenläsion.

Aneurysmal bone cyst is a benign osteolytic lesion in childhood and adolescence which primarily arises in metaphyseal long bones. Its presence in bones of the skull base is very rare. In a 3-year old girl presenting with proptosis, MRI demonstrated a well-defined displacing growing mass in the ethmoid sinus, orbita and anterior fossa. The histopathologic examination of biopsy specimens confirmed an aneurysmal bone cyst. Despite radical surgery the child suffered from two recurrences of the lesion in the first year after initial diagnosis. There has been no subsequent recurrence during the last 3 years. Since this lesion is rarely seen at the skull base, is difficult to differentiate clinically and by histopathology and may take an abnormal course, it is described in this case report to emphasize that it should be included in the differential diagnosis of ENT tumors at this location.

[Treatment of lacrimal stenosis. Causes, diagnostics, and surgical procedures]. / Behandlung von Tränenwegsstenosen. Ursachen, Diagnostik und operatives Vorgehen.

The nasolacrimal system lies in direct proximity to the nasal cavity and the paranasal sinuses. Consequently, different nasal pathologies may influence the lacrimal drainage system. Hence, a standardized rhinological examination using endoscopy and, when indicated, modern imaging is mandatory to clarify malfunctions of lacrimal drainage. This paper describes the different possible causes and the necessary diagnostic tools from an ENT physician's point of view. Furthermore, the results of a series of 48 patients with endoscopic dacryocystorhinostomy performed between 2005 and 2008 were entered into the study. Follow-up examination of these patients showed satisfactory results in 91% and complete reduction of symptoms in 82%. Accompanying surgical procedures were done in 14 patients (septoplasty, infundibulotomy, or reduction of the middle turbinate).

[Risk of nanoparticles?]. / Risiken durch Nanopartikel?

Nanotechnology is an "emerging industry" and becomes more widely used. As a result human exposure to nanoparticles is inevitable. Exposure to nanoparticles can affect the upper aerodigestive tract, before particles reach lung, stomach and intestine. The effects of this passage depend on particle size, particle concentration, the kind of the particle and the duration of contact. Only few in-vitro-investigations about effects of the exposition of nanoparticles on the mucous cells of oral cavity, nose and nasal sinuses exist. In-vitro-analysis with cells of nasal mucous membrane exposed to nanoparticles showed a release of mediators involved in inflammation and allergy development. Cytotoxic and genotoxic effects could be found for several nanoparticles (e.g. carbon nanotubes) in vitro. Due to different size, structure, chemical and physical properties nanoparticles can not be summarized in a homogenous group; quite the contrary risk evaluation of nanoparticles must be carried out case-related. Today toxicological risks can not be evaluated sufficiently. Biological interactions and tissue permeability of manufactured nanoparticles is a major issue for further investigations. In this report the use and health effects of nanoparticles are overviewed.

[Papillary thyroid carcinoma in a thyroglossal duct cyst: primary tumor or metastasis?]. / Papilläres Schilddrüsenkarzinom in einer medianen Halszyste : Primärtumor oder Metastase?

Thyroglossal duct cysts are the most common anomaly in thyroid development. The occurrence of carcinoma in a cyst is reported to be about 1% of cases. Histopathological examinations reveal a papillary thyroid carcinoma in about 94% of these. We report the case of 38-year-old female having a massive, cervical cystic mass over a period of 18 months. An ectopic papillary thyroid carcinoma was diagnosed. A total thyoidectomy and bilateral neck dissection were performed. This revealed a small thyroid carcinoma and three positive lymphatic nodes. Whether the cystic carcinoma is the primary or a metastasis of the thyroid carcinomais discussed.

[Metastasis to the lateral skull base]. / Metastase eines Trachealkarzinoms im Bereich der Felsenbeinspitze.

BACKGROUND: Tumours and metastases of the lateral skull base are rare findings. Clinically, the progressive involvement of ipsilateral cranial nerves is important. CASE REPORT: A 69-year-old man presented with headache and palsies of the facial nerve and nerve VI. Furthermore, he had hearing loss and hypaesthesia of the trigeminal nerve (V3). Four months previously, laser therapy for carcinoma of the trachea (cT4 cN3 cM0) had been done. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed an intrapetrosal mass with destruction of the lateral skull base. The findings suggested a metastasis of the tracheal carcinoma. We performed a mastoidectomy with specimen collection, and the pathological analysis revealed infiltration of a squamous cell carcinoma. The patient died within 3 weeks after radiotherapy with palliative intention despite malignant progression. CONCLUSION: The diagnosis and therapy of metastases to the lateral skull base is an interdisciplinary challenge. CT and MRI scans are essential for planning further procedures. In cases of headache and cranial nerve palsies, a metastasis to the lateral skull base must be considered in the differential diagnosis.

[Tuberculosis of the parotid gland]. / Tuberkulose in der Glandula parotidea.

The different tumours of the parotid gland can be divided in benign or malignant tumours, regional inflammations and enlarged lymph nodes. We report on a 26-year-old male from Uganda with a slowly growing tumour of the right parotid gland for several months. The CT scan showed a poorly defined intraparotideal tumour. Ultrasonography revealed multiple enlarged cervical lymph nodes. Suspecting a neoplasm of the parotid gland we decided to perform a superficial parotidectomy for histological examination. The pathological analysis revealed a caseous necrosis and epitheloid granulomata containing Langhans giant cells. The polymerase chain reaction could not confirm our suspicion of tuberculosis. The Ziehl-Neelsen staining did not show any acid-proof rods. Only the breeding of the suspicious probes generated Mycobacterium tuberculosis. Initially denying any infections the patient admitted to having had tuberculosis that had been treated with antibiotics 2 years previously. Tuberculosis is a rare finding in parotid tumours. It must be considered as a differential diagnosis of parotid enlargements.

[Foreign body reaction to materials implanted as biocompatible for internal fixation]. / Fremdkörperreaktion nach Implantation eines biokompatiblen Osteosynthesesystems.

After implantation of resorbable materials for internal fixation, foreign body reactions are described in 0-47% of cases. Copolymers of poly-l-lactic acid (PLLA) and polyglycolic acid (PGA) seem to offer better biocompatibility than other materials. One of our patients had a midfacial fracture, which we fixed using a resorbable system based on PLLA-PGA (82%-18%); a foreign body reaction developed after 22 months. When resorbable materials are used it is essential to be aware specifically of the risk of foreign body reactions, especially when the facial area is involved. This risk must be discussed with the patient in some detail during the preoperative period.