Optical magnification devices in tonsillectomy: a prospective randomised clinical study.

Tonsillectomy is one of the most common surgical procedure in otorhinolaryngology. A plethora of approaches has been undertaken so far to limit postoperative pain, one of the major problems patients are concerned with. Thermal damages of the surrounding tissue caused by coagulation during surgery are discussed to correlate with postoperative pain. Therefore, we studied whether the use of magnification devices reduced coagulation procedures and consequently limited post-operative pain. Following an intraindividual design, we performed tonsillectomy on one side using a microscope or magnifying glasses whereas the opposite side was operated with unsupported vision. As verified by a visual analogue scale, our study shows that neither the use of a microscope, nor the use of magnifying glasses leads to less post-operative pain. Other parameters like post-operative bleeding, duration of surgery, and total applied energy by bipolar coagulation were also comparable in the different treatment groups. Taken together, magnification-supported tonsillectomy does not seem to be appropriate for limiting complications of tonsillectomy, especially not for reducing post-operative pain.

Mental distress and effort to engage an image-guided navigation system in the surgical training of endoscopic sinus surgery: a prospective, randomised clinical trial.

The use of image-guided navigation systems in the training of FESS is discussed controversy. Many experienced sinus surgeons report a better spatial orientation and an improved situational awareness intraoperatively. But many fear that the navigation system could be a disadvantage in the surgical training because of a higher mental demand and a possible loss of surgical skills. This clinical field study investigates mental and physical demands during transnasal surgery with and without the aid of a navigation system at an early stage in FESS training. Thirty-two endonasal sinus surgeries done by eight different trainee surgeons were included. After randomization, one side of each patient was operated by use of a navigation system, the other side without. During the whole surgery, the surgeons were connected to a biofeedback device measuring the heart rate, the heart rate variability, the respiratory frequency and the masticator EMG. Stress situations could be identified by an increase of the heart rate frequency and a decrease of the heart rate variability. The mental workload during a FESS procedure is high compared to the baseline before and after surgery. The mental workload level when using the navigation did not significantly differ from the side without using the navigation. Residents with more than 30 FESS procedures already done, showed a slightly decreased mental workload when using the navigation. An additional workload shift toward the navigation system could not be observed in any surgeon. Remarkable other stressors could be identified during this study: the behavior of the supervisor or the use of the 45° endoscope, other colleagues or students entering the theatre, poor vision due to bleeding and the preoperative waiting when measuring the baseline. The mental load of young surgeons in FESS surgery is tremendous. The application of a navigation system did not cause a higher mental workload or distress. The device showed a positive effort to engage for the trainees with more than 30 FESS procedures done. In this subgroup it even leads to decreased mental workload.

Specific stressors in endonasal skull base surgery with and without navigation.

The goal of modern organizational psychology is to recognize, anticipate and finally avoid stress situations. The aim of this study was to measure objectively the mental and physical demands during transnasal surgery with and without the aid of a navigation system. Forty endonasal surgeries (20 with and 20 without navigation, not blinded and not randomized) done by four different experienced rhinosurgeons (>250 FESS procedures done) were included. The heart rate, the heart rate variability, the respiratory frequency and the masseter tone were monitored as biometrical parameters by the surgeons during the whole surgery for the quantification of mental demand. Stress situations could be identified during the procedures by an increase in the heart rate and a decrease in the heart rate variability. Stress level in procedures with navigation did not significantly differ from procedures without navigation. Interestingly, in 10 % of the cases a navigation system would have been helpful, although the surgeon stated before the procedure that such a system would not be necessary. Other stressors could be identified like time pressure, students or colleagues speaking with the surgeon or chatting in the OR and system failure of medical devices, i.e. navigation, sinus drill, electrocautery or shaver. Surgical stressors blurred vision due to diffuse bleeding and drill out procedures in the sphenoid sinus. Calming situations were a quiet atmosphere in the OR (i.e. closed doors) and the participation of another experienced colleague, especially a neurosurgeon. Stress situations occur when complex medical devices like the navigation do not work. For their proper function it is important that the whole OR-team is trained with it. Unqualified or unmotivated OR personnel create stress for the surgeon and disharmony in the team, which then ends in inadequate behaviour.

Diode laser versus radiofrequency treatment of the inferior turbinate - a randomized clinical trial.

BACKGROUND: Laser and radiofrequency induced volume reduction of the inferior turbinates are frequently used treatment modalities. Which of both is superior, however, is not clear to date due to a lack of controlled prospective studies. Here, we compare both methods regarding improvement of nasal breathing, complications, patient comfort and wound healing. METHODOLOGY: Prospective, randomized, single-blinded clinical trial with intra-individual design. After randomization, one side of the nose was treated with a 940nm diode laser and the other side with bipolar radiofrequency therapy. Pre- and postoperative evaluation was performed using visual analogue scales, nasal endoscopy and objective measurements of nasal patency. RESULTS: Of 27 enrolled patients, 26 completed the protocol. No severe complications were observed. Intraoperative discomfort was significantly more severe on the radiofrequency side. After three months, a significant reduction of nasal obstruction was observed for laser treatment and radiofrequency therapy with no significant difference between them. Objective parameters did not improve significantly. When asked which treatment modality they would chose again 50 % of the patients decided for radiofrequency treatment, 23 % for laser treatment, and 19 % for both. CONCLUSION: DLVR and RFVR are well-tolerated treatment modalities and both significantly reduce the degree of nasal obstruction in patients with hypertrophic inferior turbinates. There was no significant difference between both treatment modalities regarding efficiency.

[Adeno-tonsillectomy in children: preoperative coagulation screening and bleeding complications]. / Präoperative Gerinnungsdiagnostik und Blutungskomplikationen bei Tonsillenchirurgie im Kindesalter.

BACKGROUND: In 2006 German medical societies published recommendations: Before carrying out an adenoidectomy and/or a tonsillectomy in childhood a specific bleeding-anamnesis should be performed instead of a laboratory coagulation screening in order to determine a clinically relevant bleeding disorder. In the context of this survey it was investigated how many of the Bavarian ENT physicians in private practice had implemented these recommendations and what experiences they made with them. In addition, further data such as the number of performed operations and occurred bleeding complications were collected. METHOD: Between 2009 and 2010 a prepared questionnaire was sent to all Bavarian ENT physicians, who were in private practice. If even after further sent covering letters no reply was received they were contacted by telephone. The analysis period was 2008. RESULTS: In total 601 ENT physicians were contacted, whereas 495 valid replies could be obtained (rate of valid return>80%). 325 (66%) of these performed surgery in 2008, but only one of 3 of these operating ENT physicians had completely implemented the recommendations. The rate of postoperative bleeding complications following tonsillectomy was 1.80%, following adenoidectomy 0.30%. A significant difference in the postoperative bleeding rate between those, who had implemented the recommendations and those, who had not, could not be shown. But a highly significant difference favouring the surgeons, who quantitatively had performed more tonsillectomies could be revealed. CONCLUSION: The results of this retrospective survey support the recommendations given by German medical societies.

Resonator properties of paranasal sinuses: preliminary results of an anatomical study.

BACKGROUND: The contribution of the nasal and paranasal cavities to vocal tract resonator properties is unclear as are voice effects of sinus surgery. Here we investigate resonance phenomena of paranasal sinuses with and without selective occlusion of the middle meatus and maxillary ostium in a cadaver. METHODOLOGY: Nasal and paranasal cavities of a Thiel-embalmed cadaver were excited by sine-tone sweeps from an earphone in the epipharynx. The response was picked up by a microphone at the nostrils. Different conditions with blocked and unblocked middle meatus were tested. Additionally, infundibulotomy was performed allowing direct access to and selective occlusion of the maxillary ostium. RESULTS: Responses showed high reproducibility. Minor effects appeared after removal of meatal occlusion. A marked low frequency dip was detected after removal of occlusion of maxillary ostium following infundibulotomy. CONCLUSION: Reproducible frequency responses of nasal tract can be derived from cadaver measurements. Marked acoustic effects of the maxillary sinus appeared only after direct exposure of the maxillary ostium following infundibulotomy.

[Tonsillitis and sore throat in childhood]. / Erkrankungen der Gaumenmandeln im Kindesalter.

Surgery of the tonsils is still one of the most frequent procedures during childhood. Due to a series of fatal outcome after hemorrhage in children in Austria in 2006, the standards and indications for tonsillectomy slowly change in Germany since that. However, there exist no national guidelines and the frequency of tonsil surgery varies in the country. In some districts eight times more children were tonsillectomized than in others. A tonsillectomy in children under 6 years should only be done if the child suffers from recurrent acute bacterially tonsillitis. In all other cases (i. e. hyperplasia of the tonsils) the low risk partial tonsillectomy should be the first line therapy. Postoperative pain and the risk of hemorrhage are much lower in partial tonsillectomy (= tonsillotomy). No matter whether the tonsillotomy is done by laser, radiofrequency, shaver, coblation, bipolar scissor or Colorado needle, as long as the crypts are kept open and some tonsil tissue is left behind. Total extracapsular tonsillectomy is still indicated in severely affected children with recurrent infections of the tonsils, allergy to antibiotics, PFAPA syndrome (periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis) and peritonsillar abscess. With regard to the frequency and seriousness of the recurrent tonsillitis the indication for tonsillectomy in children is justified if 7 or more well-documented, clinically important, adequately treated episodes of throat infection occur in the preceding year, or 5 or more such episodes occur in each of the 2 preceding years (according to the paradise criteria). Diagnosis of acute tonsillitis is clinical, but sometimes it is hard to distinguish viral from bacterial infections. Rapid antigen testing has a very low sensitivity in the diagnosis of bacterial tonsillitis and swabs are highly sensitive but take a long time. In all microbiological tests the treating physician has to keep in mind, that most of the bacterials, viruses and fungi belong to the healthy flora and do no harm. Ten percent of the healthy children bear even streptococcus pyogenes all the time in the tonsils with no clinical signs. In these children decolonization is not necessary. Therefore, microbiological screening tests in children without symptoms are senseless and do not justify an antibiotic treatment (which is sometimes postulated by the kindergartens). The acute tonsillitis should be treated with steroids (e.g. dexamethasone), NSAIDs (e.g. ibuprofene) and betalactam antibiotics (e.g. penicillin or cefuroxime). With respect to the symptom reduction and primary healing the short-term late-generation antibiotic therapy (azithromycin, clarithromycin or cephalosporine for 3 to 5 days) is comparable to the long-term penicilline therapy. There is no difference in the course of healing, recurrence or microbiological resistance between the short-term penicilline therapy to the standard 10 days therapy, as well. On the other hand, only the 10 days antibiotic therapy has prooven to be effective in the prevention of rheumatic fever and glomerulonephritic diseases. The incidence of rheumatic heart disease is currently 0.5 per 100.000 children in school age. The main morbidity after tonsillectomy is pain and the late hemorrhage. Posttonsillectomy bleeding can occur till the whole wound is completely healed, which is normally after 3 weeks. Life-threatening hemorrhages occur often after smaller bleedings, which can spontaneously cease. That is why every hemorrhage, even the smallest, has to be treated properly and in ward. Patients and parents have to be informed about the correct behavior in case of hemorrhage with a written consent before the surgery. The handout should contain important adresses, phone numbers and contact persons. Almost all cases of fatal outcome after tonsillectomy were due to false management of hemorrhage. Especially in small children hemorrhage can be life-threatening because of the lower blood volume and the danger of aspiration with asphyxia. A massive hemorrhage is an extreme challenge for every paramedic or emergency doctor because of the difficult airway management. Intubation is only possible with appropriate unflexible suction tubes. All different surgical techniques have the risk of hemorrhage and even the best surgeon will experience a postoperative hemorrhage. The lowest risk of hemorrhage is after cold dissection with ligature or suturing. All "hot" techniques with laser, radiofrequency, coblation, mono- or bipolar forceps have a higher risk of late hemorrhage. Children with a hereditary coagulopathy have a higher risk of hemorrhage. It is possible, that these children were not identified before surgery. Therefore it is recommended by the Society of paediatrics, anaesthesia and ENT, that a standardised questionnaire should be answered by the parents before tonsillectomy and adenoidectomy. This 17-points-checklist questionnaire is more sensitive and easier to perform than a screening with blood tests (e.g. INR and PTT). Unfortunately, a lot of surgeons still screen the children preoperatively by coagulative blood tests, although these test are inappropiate and incapable of detecting the von Willebrand disease, which is the most often coagulopathy in Europe. The preoperative information about the surgery should be done with the child and the parents in a calm and objective atmosphere with a written consent. A copy of the consent with the signature of the surgeon and both custodial parents has to be handed out to the parents.

Endoscopic sinus surgery training courses: benefit and problems - a multicentre evaluation to systematically improve surgical training.

BACKGROUND: The aim of this multicentre study was to systematically analyse the strengths and weaknesses in the surgical training for endoscopic sinus surgery (ESS) and identify measures that may improve training. METHODOLOGY: Using a structured questionnaire, 133 participants of ESS courses in seven centres in Germany, Switzerland and Australia were asked about their experiences during their dissection courses and how they perceived their course could be improved. RESULTS: Gaining confidence in handling of instruments and endoscopes was only a problem for participants with little experience in ESS. The majority of the participants, independent from their level of training, considered infundibulotomy and anterior ethmoidectomy as the easiest dissection steps, whilst surgery of the frontal sinus posed a considerable challenge for many surgeons even those with a higher level of training. Participants with and without ESS experience thought that emphasis on anatomy was the most important improvement that could be made during their surgical training. Virtually all participants stated that the course improved their anatomical knowledge, their surgical skills and their confidence when performing ESS. CONCLUSIONS: ESS dissection courses are considered beneficial by surgical trainees. Participants felt that more emphasis on sinus anatomy in conjunction with private study is essential to maximize their skills in surgical dissection. For beginners with ESS, an infundibulotomy and anterior ethmoidectomy were thought to be the best initial procedures to help develop endoscopic surgical skills.

[Exostoses of the external auditory canal in professional diving. A case for the German Social Accident Insurance Institution]. / Berufstaucher mit Gehörgangsexostosen. Ein Fall für die Berufsgenossenschaft.

Exostoses of the external auditory canal are often diagnosed incidentally but may also cause complications, e.g., conductive hearing loss and/or recurrent inflammations of the external ear canal due to stenosis. This paper presents current scientific data on the pathogenesis of ear canal exostoses, which obviously focus on the cold water hypothesis. We present a case of an expert opinion on occupational illness and discuss whether the legal preconditions for recognition "like an occupational disease" according to article 9(2) Social Code Book VII are met. A systematic reporting of suspected cases is recommended in order to obtain reliable data on the epidemiology and the clinical course of external auditory exostoses among individuals occupationally exposed to cold water and to enter an expert discussion on the reasonability of an inclusion in the list of occupational diseases.

Evaluation of an image-guided navigation system in the training of functional endoscopic sinus surgeons. A prospective, randomised clinical study.

INTRODUCTION: Many sinus surgeons report improved spatial orientation after using a navigation system. This study investigates the surgical, ergonomic and economic aspects of using a navigation system in training and teaching. MATERIALS AND METHODS: Eight rhino-surgeons in training and 32 patients with bilateral diseases of the paranasal sinus system were included. After randomisation, one patient`s side was operated on with a navigation system while the other side was operated on without navigation. It was monitored how often the surgeon used the navigation pointer and then changed the procedures. A standardised and validated interview recorded the cognitive load when using the navigation system and the application efficiency. RESULTS: The operations lasted on average 16 minutes longer with the navigation. Five paranasal sinuses could not be found in the control group without navigation. In only 10-13% of cases did the surgical procedure change after the use of the pointer. Most of the surgeons admitted that particular steps of the operation were more reliable and safer to carry out with the navigation system. The general trust in the system rose in proportion to intraoperative accuracy and repeated use. CONCLUSION: Overall, there was an overwhelming level of trust in the navigation system. Trainee sinus surgeons seeing their more experienced colleagues using a navigation device tend to overestimate the possibilities of the system and to underestimate the risks. The assistance system was used particularly effectively in the group of slightly more experienced surgeons. In this group, the additional expenditure of time was less and the navigation substantially contributed to reinforcing the anatomical sense of direction.

[FESS and surgical training: what are the problems?]. / FESS und Ausbildung: Wo liegen die Probleme?

BACKGROUND: The literature lacks studies analyzing the specific problems of colleagues in the surgical training for FESS. The presented date can help to systematically improve the training. METHODS: The participants of the 11 (th) Munich FESS Course were asked about problems occurring during dissection and about their opinion how the training could be improved. RESULTS: Handling of instruments and endocopes was only a problem for participants without any experience in FESS. The majority of the participants, independently from their training level, considered infundibulotomy and anterior ethmoidectomy the easiest dissection steps. Participants with and without FESS experience regarded a more extensive study of anatomy in the forefront as the most important toehold in the improvement of the surgical training. Virtually all participants stated that the course improved their anatomical knowledge, their confidence on the patient, and their surgical skills. CONCLUSIONS: FESS dissection courses are well accepted and considered as beneficial by surgical trainees. An exhaustive private study of anatomy is essential. For beginners with FESS, infundibulotomies and anterior ethmoidectomies should preferentially be chosen.

[Angiotensin-converting enzyme inhibitor induced angioedema : new therapy options]. / "Angiotensin-converting-enzyme"-Hemmer induziertes Angioödem : Neue Therapieoption.

Angiotensin-converting enzyme (ACE) inhibitors block the catalysis of angiotensin I to angiotensin II and also the breakdown of bradykinin. ACE inhibitor-induced angioedema is mediated by inhibited bradykinin degradation leading to enhanced bradykinin plasma levels. The efficacy of currently used standard treatments with antiallergic drugs is questionable. A patient with acute ACE inhibitor-induced angioedema was treated with icatibant, a specific bradykinin B2 receptor antagonist approved for the treatment of hereditary angioedema. A single subcutaneous injection of 30 mg icatibant resulted in a rapid onset of symptom relief and a remarkable shortening of duration of the attack.

Postoperative bleeding in paediatric ENT surgery. First results of the German ESPED trial.

Bleeding after ear-nose-and throat surgery in children is a serious complication. With the help of the German Surveillance Unit for Rare Paediatric Disorders (Erhebungseinheit für seltene pädiatrische Erkrankungen in Deutschland; ESPED) a two year survey was performed to record the incidence, severity, reasons and treatment of haemorrhages. During the study period, 1069 bleeds were reported from 720 paediatric hospitals and departments of otorhinolaryngology after adenoidectomy and tonsillectomy. 713 reports could be analyzed. Two deaths occurred after adenoidectomy. Although laboratory screening was performed in more than 70% of all cases, bleeding complications were neither foreseeable nor preventable. Inherited coagulopathies were rare and in most cases not detected, neither by laboratory screening nor by taking a history. Since preoperative measures cannot help much to improve the situation, all efforts have to be taken to improve the postoperative period, especially since more than 20% of the hemorrhages occurred during weekends. Guidelines on postoperative care and behaviour should therefore be implemented and parents and patients must be informed on bleeding risks and on what to do in case of emergency. If bleeding occurs, extensive coagulation testing is mandatory.

Double-blind, randomised, controlled study of post-operative pain in children undergoing radiofrequency tonsillotomy versus laser tonsillotomy.

INTRODUCTION: In the last decade tonsillotomy has come into vogue again, whereas the number of tonsillectomies is decreasing rapidly. Currently, most tonsils are reduced by utilise electrosurgery, radiofrequency or carbon dioxide laser. However, it is not clear whether radiofrequency tonsillotomy is as effective as laser or other surgical techniques in respect of post-operative pain and haemorrhage. MATERIAL AND METHODS: A prospective, randomised, double-blinded, controlled, clinical study was conducted in the otorhinolaryngology department of Ludwig Maximilians University, Munich, Germany. Twenty-six children with tonsillar hypertrophy were included. Exclusion criteria were: history of peritonsillar abscess, previous tonsil surgery, tonsillitis within two weeks, pain before surgery, psychiatric illness, asymmetrical tonsils, chronic analgesic usage, bleeding disorders and other surgical procedures during the same operation. Tonsillotomy was performed on one side with radiofrequency and on the other side with a carbon dioxide laser. All procedures were performed by a single surgeon, under general anaesthesia. A visual analogue scale was used to measure patients' pain on each side, administered by a 'blinded' nurse on the three post-operative mornings and evenings, within the hospital. RESULTS: There was no difference in post-operative pain scores or haemorrhage, comparing laser versus radiofrequency tonsillotomy. Patient's overall reported pain was very modest compared with post-tonsillectomy pain. No haemorrhage or other adverse effects were observed.

Frontal sinus obliteration--a successful treatment option in patients with endoscopically inaccessible frontal mucoceles.

OBJECTIVE: This study evaluates non-standardized subjective patient satisfaction- and clinical outcome variables following frontal sinus obliteration with abdominal fat in endoscopically inaccessible mucoceles. METHODS: In a retrospective chart review, all patients who underwent frontal sinus obliteration for endoscopically inaccessible mucoceles at the Ludwig Maximilian University in Munich between 1996 and 2006 were identified and the postoperative outcomes were evaluated by a non-standardized patient questionnaire rating the degree of symptoms before and after surgery. Additionally, the postoperative clinical status and MRI-scans were analysed in a subgroup of patients. RESULTS: Nine out of 10 patients were generally satisfied with the obliteration. Most had a significant improvement in their main symptoms and reported a decrease in annual days of missed work and a reduced use of disease-specific drugs. The sense of smell and the intensity of postnasal dripping remained subjectively unchanged. Seventy percent of patients complained about temporary pain at the abdominal donor side. CONCLUSIONS: Based on these results, osteoplastic frontal sinus obliteration using abdominal fat seems to be a successful treatment option in patients in whom mucoceles of the frontal sinus are not endoscopically accessible.

[Hybrid operation for a distal aortic arch aneurysm causing left recurrent nerve palsy - Ortner's syndrome]. / Hybridoperation zur Behandlung eines distalen Aortenbogenaneurysmas mit linksseitiger Recurrensparese - Ortner-Syndrom.

BACKGROUND: A left recurrent nerve palsy caused by left atrium hypertrophy, dilatation of the left pulmonary artery or a thoracic aortic arch aneurysma is named Ortner's syndrome. CASE REPORT: We report the case of a 84-year old male patient with a posttraumatic aneurysm of the distal aortic arch known for 20 years, which became symptomatic by new presentation of an acute hoarseness caused by a left sided recurrent nerve palsy due to rapid aneurysma expansion. Because of the aneurysma localization, the advanced age and the patient?s morbidity he was treated by a hybrid procedure with an extrathoracic reconstruction of the supraaortic arteries by a right to left carotid-carotid bypass and transposition of the left subclavian artery followed by endovascular implantation of aortic stent grafts for aneurysma exclusion. The left recurrent nerve palsy remained unchanged until now. CONCLUSIONS: Aneursms of the distal aortic have to be considered as a rare cause of a left-sided recurrent nerve palsy. Recent advances in endovascular therapy combined with supraaotic vascular reconstruction offers a less invasive therapeutic option for some of these patients.

[Quincke's edema: diagnosis and management of 102 patients with sudden upper airway obstruction]. / Quincke-Odem: Diagnose und Management von 102 Patienten mit plötzlichem Larynxödem.

BACKGROUND: Hereditary angioedema (HAE) is extremely rare and clinically characterized by recurrent and self-limiting skin, intestinal and life threatening laryngeal edema. Because of the danger of asphyxiation, it is vital that acute attacks of laryngeal edema be interrupted immediately. The aim of this study is to provide information on the incidence, diagnosis and treatment of laryngeal edema with upper airway obstruction in general and due to HAE. METHODS: 102 patients with swelling of the larynx and difficulty in breathing (stridor) and 21 patients with a manifest HAE were surveyed at the Department of Otorhinolaryngology, Head and Neck Surgery of the Ludwig-Maximilians-University of Munich from 2001 to 2004. RESULTS: 63% of the laryngeal swellings with airway obstruction were due to radiotherapy in cancer and the intake of ACE-Inhibitors. Just 22% were due to allergic reactions. Only one patient (< 1%) suffered from HAE. All patients were treated with intravenous steroids and anti-histamines successfully, except the HAE patient. After emergency coniotomy the patient was treated with purified C1 inhibitor concentrate (C1-INH). CONCLUSIONS: According to our experience almost all patients with laryngeal swelling and upper airway obstruction react well to the standard therapy with steroids and anti-histamines. In contrast these drugs have no effect on HAE. Replacement therapy with C1-INH has proved to be effective. The challenge is to realize whether an airway obstruction is due to HAE or not. In this case, careful observation, the right medication and an appropriate airway management are lifesaving. The possibility of sudden airway obstruction and asphyxiation must be discussed with these patients and their relatives.

Computer-assisted surgery of the paranasal sinuses: technical and clinical experience with 368 patients, using the Vector Vision Compact system.

INTRODUCTION: This paper presents our experience with a navigation system for functional endoscopic sinus surgery. In this study, we took particular note of the surgical indications and risks and the measurement precision and preparation time required, and we present one brief case report as an example. MATERIALS AND METHODS: Between 2000 and 2004, we performed functional endoscopic sinus surgery on 368 patients at the Ludwig Maximilians University, Munich, Germany. We used the Vector Vision Compact system (BrainLAB) with laser registration. The indications for surgery ranged from severe nasal polyps and chronic sinusitis to malignant tumours of the paranasal sinuses and skull base. RESULTS: The time needed for data preparation was less than five minutes. The time required for preparation and patient registration depended on the method used and the experience of the user. In the later cases, it took 11 minutes on average, using Z-Touch registration. The clinical plausibility test produced an average deviation of 1.3 mm. The complications of system use comprised one intra-operative re-registration (18 per cent) and one complete failure (5 per cent). Despite the assistance of an accurate working computer, the anterior ethmoidal artery was incised in one case. However, in all 368 cases, we experienced no cerebrospinal fluid leaks, optic nerve lesions, retrobulbar haematomas or intracerebral bleeding. There were no deaths. DISCUSSION: From our experience with computer-guided surgical procedures, we conclude that computer-guided navigational systems are so accurate that the risk of misleading the surgeon is minimal. In the future, their use in certain specialized procedures will be not only sensible but mandatory. We recommend their use not only in difficult surgical situations but also in routine procedures and for surgical training.