Rotational tomography of the normal and reconstructed middle ear in temporal bones: an experimental study.

Imaging is an essential diagnostic tool in reconstructive middle ear surgery, especially in pre-operative planning. Due to ongoing improvement of imaging quality and development of new imaging techniques like e.g. rotational tomography (RT) post-operative follow-up and immediate evaluation of surgical results may become more important. The aim of this experimental study was to evaluate RT as a new tool for postoperative determination of middle ear anatomy and implant position in temporal bones. RT was performed in ten temporal bone specimen after insertion of different middle ear prostheses concerning material, shape and length (PORP; TORP; Stapes piston). An implantable hearing device (Symphonix Soundbridge) was also implanted and visualized. For comparison some specimen additionally underwent conventional computed tomography (CT), including the newest technology. Characterization of anatomical structures of the temporal bone using RT was of comparable quality to conventional CT-scans in all investigated specimen while requiring approximately 30% of the CT's irradiation exposure. Unlike CT the RT showed almost no problems due to metallic artefacts of the implanted prostheses. Furthermore RT enabled a 3-dimensional view of the temporal bone and angle determination of inserted prostheses towards the tympanic membrane and/or the malleus handle. Detailed imaging of the prostheses allowed determination of shape, material and localization within the specimen's reconstructed middle ear. The new imaging technique of RT allows precise presentation of anatomical structures and middle ear implants in temporal bones. Following these experimental results it will be our future work to evaluate this method in clinical practise.

[Is the observation of patients with sleep-apnea-syndrome after surgery of the upper airway in an intensive care unit generally necessary?]. / Ist die postoperative Uberwachung von Patienten mit schlafassoziierten Atemstörungen nach Nasenoperationen auf einer Intensivstation erforderlich?

BACKGROUND: Although it is known that after surgery of the nose and/or the paranasal sinuses serious complications can arise for patients suffering from Sleep-Apnea-Syndrome (SAS), there exists no general recommendation for postoperative care of these patients. This retrospective analysis is dealing with the question whether it is generally necessary to observe SAS-patients after nasal surgery including intubation in an Intensive Care Unit (ICU). PATIENTS AND METHODS: 24 Patients of the ORL-Dept., Marienkrankenhaus Hamburg, suffering from SAS underwent surgery of the nose, the paranasal sinuses and/or the pharynx including total intravenous anesthesia (TIVA) during the period of 1. 10. 2000 until 1. 5. 2004. SAS was diagnosed in 6 cases due to defined clinical criteria and in 18 cases due to the polysomnographic findings in the sleeping laboratory's examination. All patients were observed postoperatively for one night in an ICU. The anesthesia protocol and the intensive care curve of each patient were systematically evaluated with special regard of the following parameters: Risk factors (Body Mass Index; other diseases, ASA-classification), premedication drugs, duration of the surgery, drugs for pain relief, lowest O2-saturation of blood, lowest heartrate, highest systolic blood pressure, adverse effects, intensive care interventions. RESULTS: Intensive care interventions were never needed. 2 patients received a low dosage of oxygeninsufflation via a face mask, in 5 cases calcium-antagonist drugs were administered due to high blood pressure and in 1 case Metamizole administration was necessary due to high temperatures. An accompanying bradycardia of the same patient was treated by administration of Atropine. The lower average O2-saturation was 93.6 +/- 1.7 % (Minimum value: 89 %). The maximum systolic blood pressure was 165.8 +/- 21.2 mm Hg and the lowest average heart rate was 65.4 +/- 13.2 bpm. CONCLUSIONS: Patients suffering from a mild to moderate SAS do not need a general postoperative surveillance in an ICU if the chosen form of anesthesia is considered concerning this sickness.

[The valence of dilatational tracheotomy]. / Zur Wertigkeit der Dilatationstracheotomie.

After standardizing surgical procedures around 1900 Shelden, Toye, Weinstein and Ciaglia developed the percutaneous dilational tracheotomy (PDT). At present it is recognized that about 50 % of the anesthesiological Intensive care Units (ICU) in Germany are using the PDT while favoring the Ciaglia-technique in the majority of cases. Further techniques are known as Griggs-, Fantoni-, Percu-Twist- and Blue-Rhino-method. Some of these are relatively new, therefore making critical comparison with other methods almost impossible due to lack of experience. The most feared complications of PDT are injury of the cricoid cartilage or of the rear tracheal wall as well as paratracheal positioning of a tracheotomy tube. Comparison between PDT and surgical techniques are difficult due to certain contraindications for PDT which are not valid for surgical procedures. Consecutively PDT will not be able to substitute surgical tracheotomy in the future. It furthermore can't be advocated as an alternative therapeutic option for mobile in-patients outside the ICU.