[Stereotactic telepresence in otorhinolaryngologic surgery]. / Stereotaktische Telepräsenz in der Hals-, Nasen- und Ohrenchirurgie.

BACKGROUND: Intraoperative three-dimensional (3D) navigation systems determine spatial positions and visualize them in radiological data sets. Usually, data from 3-D computed tomography (CT) are used. We have successfully implemented "augmented reality" in routine clinical practice by superimposing positional data and guiding and ancillary structures on the live endoscopic video of the operating site. Thus, optimal access paths and anatomical structures such as the a. carotis interna or the n. opticus can be displayed. METHODS AND RESULTS: With modern telecommunication, any two locations can be connected for intraoperative consultations with a remote expert, and 3D navigation is an ideal complement. We have successfully tested telephone, ISDN, Ethernet, and ATM technology intraoperatively and find that the ARTMA system provides well-developed technology. CONCLUSIONS: Stereotactic telepresence can provide essential aid in difficult surgical procedures, and the ARTMA Knowledge-Guided Surgery system will contribute further to the optimization of computer-assisted surgery.

Local application of granulocyte-macrophage colony stimulating factor (GM-CSF) for the treatment of oral mucositis.

The combination of radiation and chemotherapy administered for patients undergoing therapy for advanced head and neck neoplasms leads to a significant rise in toxic side-effects. Oral mucositis remains one of the most distressing factors leading to pain, impairment of oral nutrition, local and systemic infection and often cessation of the oncological treatment. The local and systemic administration of recombinant growth factors has revealed a potential benefit in the treatment of oral mucositis. Clinical data concerning the topical use of granulocyte-macrophage colony-stimulating-factor (GM-CSF) in the prevention and therapy of mucositis in patients undergoing radiochemotherapy for advanced cancer of the head and neck are presented in this paper. A prospective, randomised, open parallel-grouped, single centre study at a university hospital was performed. 35 patients with stage III and IV carcinomas of the head and neck were included. Statistical analysis concerning the degree of oral mucositis, the perception of pain, the incidence of secondary infections and the change in haematological parameters revealed no superiority of GM-CSF in comparison to conventional mouthwash between the two groups of patients. As a result, and faced with the tremendous costs of the regular use of a recombinant cytokine, we ended the clinical trial after 35 patients. The topical administration of GM-CSF to treat oral mucositis as a result of radiochemotherapy in patients suffering from head and neck cancer cannot be recommended.

A full 3D-navigation system in a suitcase.

OBJECTIVE: To reduce the impact of contemporary 3D-navigation systems on the environment of typical otorhinolaryngologic operating rooms, we demonstrate that a transfer of navigation software to modern high-power notebook computers is feasible and results in a practicable way to provide positional information to a surgeon intraoperatively. MATERIALS AND METHODS: The ARTMA Virtual Patient System has been implemented on a Macintosh PowerBook G3 and, in connection with the Polhemus FASTRAK digitizer, provides intraoperative positional information during endoscopic endonasal surgery. RESULTS: Satisfactory intraoperative navigation has been realized in two- and three-dimensional medical image data sets (i.e., X-ray, ultrasound images, CT, and MR) and live video. CONCLUSIONS: This proof-of-concept study demonstrates that acceptable ergonomics and excellent performance of the system can be achieved with contemporary high-end notebook computers.

Dendritic cell vaccines for cancer therapy.

Dendritic cells (DC) are professional antigen-presenting cells whose primary function is the initiation of immune response. Based on the finding that the immune system usually fails to identify and kill cancer cells, DC have been recently used as vaccines for stimulation of tumour-specific immunity. This review focuses on pitfalls related to DC-based vaccination against solid tumours and on improvement of this immunotherapeutic approach for routine treatment of cancer disease.

Juvenile nasopharyngeal angiofibroma: management and therapy.

OBJECTIVE: To conduct a review of contemporary approaches on the diagnostic-preoperative, operative, and postoperative methods in the management of juvenile nasopharyngeal angiofibroma (JNA). STUDY DESIGN: Retrospective study of 14 cases of JNA resection at the Department of Otorhinolaryngology, University of Innsbruck (Innsbruck, Austria) between 1987 and 1998. METHODS: Data was obtained for each patient regarding age, presenting symptoms, duration of symptoms, biopsy findings, tumor location, administration of preoperative angiography and embolization, and surgical approach. The follow-up period ranged from 1 to 13 years. RESULTS: Based on the histological evaluation by the preoperative biopsy and the tumor location, several surgical approaches were applied. A transnasal endoscopic procedure was employed in seven cases. The preoperative embolization and the intranasal approach with the potassium titanyl phosphate laser minimized blood loss. The recurrence rate was at a low of 15%. CONCLUSION: The surgical approach should be determined by tumor location, tumor size, and effectiveness of tumor embolization. For patients with JNA with tumor extension involving the nasopharynx, the nasal cavity, the paranasal sinuses, and the pterygopalatine fossa, the transnasal endoscopic technique offers a minimally invasive resection of the entire tumor mass with minimal morphological disturbance.

Transnasal treatment of congenital choanal atresia with the KTP laser.

This retrospective analysis presents a minimally invasive method for a transnasal approach to treat bilateral and unilateral choanal atresia and stenosis in infants and children. We describe an advanced surgical technique that applies the use of a KTP laser and give recommendations for preoperative diagnosis and postoperative assessment. We report 13 cases of bilateral and unilateral choanal atresia or stenosis treated over a 3 1/2-year period. We used a transnasal approach and endoscopic control. For bilateral choanal atresia, the operation was performed within the first few days of birth. For unilateral choanal atresia or stenosis, surgery was performed several weeks after birth. In all cases, an intranasal stent was inserted. Our findings demonstrate that this transnasal approach provides significant benefits. A primary advantage is the diminished risk of intraoperative or postoperative complications. Additional benefits include lower rates of re-obstruction and a decreased incidence of subsequent disease, including chronic secretory otitis media.

Prognostic value of laryngeal electromyography in vocal fold paralysis.

OBJECTIVE: To analyze the value of electromyography in predicting recovery from acute neurogenic vocal fold paralysis. STUDY DESIGN: Prospective case series. SETTING: University-based hospital of otorhinolaryngology-head and neck surgery. PATIENTS: Ninety-eight patients (56 women, with a mean age of 62.2 years; 42 men, with a mean age of 39.8 years) with 111 paralyzed vocal folds. The causes were varied, with thyroid surgery (53 cases) and idiopathic palsy (18 cases) being the predominant factors. INTERVENTION: Prognostication was based on electromyography performed no earlier than 14 days after onset of palsy. Findings were classified as neurapraxy, axonotmesis, and neurotmesis. Prognosis is inherent in this classification, since neurapraxy is presumed to resolve completely within 8 to 12 weeks, whereas axonotmesis is most likely to be followed by impaired vocal fold mobility. MAIN OUTCOME MEASURES: Vocal fold mobility after 6 months. RESULTS: In 102 vocal folds, some palsy of various degree persisted after 6 months. Free mobility of the paralyzed vocal fold was restored in 9 cases. By means of laryngeal electromyography, defective recovery, defined as absence of completely free vocal fold mobility, was predicted correctly in 94.4% of cases (68/72). For complete recovery, prognosis was accurate in only 12.8% of cases (5/39). CONCLUSIONS: The detection of neural degeneration by laryngeal electromyography allows the prediction of poor functional outcome with sufficient reliability in an early phase of the disease process. Conversely, the absence of signs of degeneration does not imply that complete recovery is to be expected.

Morphology of the human thyroglossal tract: a histologic and macroscopic study in infants and children.

The anatomic development of thyroglossal tract remnants is not understood at present. For analysis of morphology and growth patterns of thyroglossal tract remnants, we used histologic whole organ serial sections to determine developmental changes through the first years of life. Larynges of 58 infants and children ages 1 month to 13 years were obtained in whole organ serial step-sections in an axial plane. The slides were stained with hematoxylin and eosin, Alcian blue, and periodic acid-Schiff stains. Altogether, 3,247 histologic slices were examined. The resulting data were then correlated with the age and sex of the specimens. We found, in 24 cases (41.3%), remnants of the thyroglossal tract or ectopic thyroid tissue. In 4 specimens (16.6%), a complete thyroglossal tract could be observed that presented a ventral path in relation to the hyoid bone with no contact with the perichondrium of the cartilage. Hormonal activity of ectopic thyroid tissue was proven in 20 cases (34.5%). Thyroid follicles were located in 2 cases (3.5%) in the hyoid bone. The thyroglossal ducts revealed a modest tendency for a left-sided pathway, whereas thyroid follicles were located more on the right paramedian side. Morphometric data on the development and structure of the thyroglossal tract and the thyroid follicles during infancy and childhood are presented. The study provides quantitative data of clinical interest that elucidate the anatomy of thyroglossal tract remnants. In addition, our investigation supports Sistrunk's operative approach for avoiding recurrences in the treatment of thyroglossal duct cysts.

Textured polydimethylsiloxane elastomers in the human larynx: safety and efficiency of use.

For the treatment of unilateral laryngeal paralysis with glottic insufficiency injection laryngoplasty is a popular modality of treatment. This procedure augments the volume of the paralyzed vocal fold by endoscopic injection. However, the ideal substance has not yet been found for that purpose. We report for the first time the systematic application and long-term results of vulcanized polydimethylsiloxane (PDMS) particles in the treatment of glottic insufficiency in the human larynx. Of 10 patients treated with PDMS in the early 1990s, 7 patients could be retrieved for reevaluation. Laryngeal function was assessed by videostroboscopy, expert rating, and further characterized by the objective parameters of voice profile and maximum phonation time. In a standardized questionnaire, all patients were asked for their personal impression of the results. Mean follow-up time was 88.4 months (range 69-102 months). Glottic closure was complete in 5 of 7 patients. There were no signs of granuloma formation or other pathologic changes of the injected vocal folds. In 4 cases, voices were rated normal or near-normal; 2 voices were rated as fair; 1 usable. All the patients reported significant and lasting voice improvement. None of the patients reported any problems related to PDMS. PDMS particles provide permanent augmentation of human vocal fold volume without complications. Their use is a valuable and safe alternative when a definitive one-step procedure seems advantageous. However, further studies are needed to assess voice improvement in comparison to other materials.

[Effects of standardized optokinetic stimuli on standing stability]. / Einfluss standardisierter optokinetischer Reize auf die Standstabilität.

BACKGROUND: Human standing stability is ensured by means of a sensory-motor control system. Proprioceptivity is most important among sensory afferences. At this time, less is known about the effect of standardized visual stimuli on motor programs towards support of body stability. These investigations were performed with special consideration for different strains on bunions and heels of both feet. METHODS: 42 healthy individuals (averaged age 29.6 years) were investigated with relaxed standing on the static force platform of Portable Multiplate System P. M. S. with optokinetic stimuli in horizontal, vertical and torsional direction (speed 80 degrees/s). Conducted by computer-analysis, the stability index, varying foot-pressure on heels and bunions, Fourier spectral analysis, and weight distribution index were counted. The eye movements were controlled with help of the PENG device. RESULTS: The optokinetic stimulations led to partial statistically significant impairments of stability particularly with torsional stimuli, yet notably improved stability with left stripes pattern. The sensory conflict between visual and other sensory inputs led to a statistically significant shift of sway frequencies to the higher ranges. On stimulation, the distribution of pressure to the feet changed. The preponderance to rest on the left side was equalized. The heels were considerably strained more with visual stimuli in all directions. Individuals felt more agreeable, toward stripes vertically directed while torsionally directed stripes elicited particular strain. CONCLUSION: Sensory conflicts between visual and other sensory inputs for maintaining the upright body position were found to impair the stability. Nevertheless these conflicts were partially compensated by motor programs more straining to the heels.

Experience with various 3-dimensional navigation systems in head and neck surgery.

OBJECTIVE: To evaluate the benefits and difficulties encountered when using various 3-dimensional (3-D) navigation systems in head and neck procedures. DESIGN: Five different navigation systems were used for preoperative planning and intraoperative 3-D navigation in procedures at the paranasal sinuses, the frontal and lateral skull bases, and the petrous bone. INTERVENTION: Intraoperative 3-D localizing systems (position-sensitive mechanical arms, infrared cameras, etc) demand reliable patient fixation on the operating table. We achieved this by developing a noninvasive head holder. Other systems allow patient movements by using magnetic digitizing technology (ARTMA System) and sophisticated programming. RESULT: Having surpassed an initial learning curve, we now achieve an accuracy of 1 to 2 mm regularly. Especially in paranasal and frontal basal surgery, all navigation systems used provide valuable positioning information during surgery. In particular for revision or tumor surgery, decisive benefits resulted from use of these systems: shorter overall operation time; safer manipulation near delicate structures; and reliable identification of the skull base even in patients with bleeding, scarring, or missing anatomical landmarks. CONCLUSIONS: We performed approximately 250 operations with different systems and introduced navigation at the lateral skull base and the petrous bone with mechanical, optic, and magnetic digitizers. In these anatomical areas, navigation was used successfully; the technical challenge is greatest at the lateral skull base, however.

Head and neck tumors: fractionated frameless stereotactic interstitial brachytherapy-initial experience.

The authors used a frameless stereotactic navigation system, the Vogele-Bale-Hohner head holder, and a targeting device to reproducibly position brachytherapy needles for fractionated interstitial brachytherapy in 12 patients with inoperable cancers of the head and neck. In all cases, deviations of the needle relative to the planned position were within 1-15 mm depending on the location of the tumor.

[Computer-aided 3D-navigation systems. Survey and location determination]. / Computerunterstützte 3D-navigationssysteme

3D-navigation systems have only recently been introduced into the surgical field. Since then they have gained increasing importance not only in ENT surgery but also in neurosurgery, orthopedic surgery, maxillo-facial surgery, radiology and radiotherapy. Following a brief historical introduction this article reviews existing navigation technologies, in terms of indication, practicability, accuracy, forensic and financial aspects. The selection of the navigation system is strongly influenced by the planned procedure (endoscopic, microscopic, open approach). According to our experience most of these systems provide useful support intraoperatively. The clinical application accuracy regularly lies in the range of 1-2 mm.

Dendritic cells in precancerous lesions of the larynx.

OBJECTIVES: Hyperplastic lesions of the laryngeal mucosa can eventually develop into squamous cell carcinoma The relationship between dendritic cell infiltration of head and neck cancers and prognosis is well known. Surprisingly, data regarding dendritic cell infiltration in precancerous lesions are not available today. It was the purpose of our study to extend these observations and to investigate in more detail the density and distribution of dendritic cells in pre-cancerous lesions. STUDY DESIGN: Retrospective survey by immunohistochemistry. METHODS: For this study we investigated paraffin-embedded tissue sections of 41 specimens. Histological diagnosis disclosed precancerous lesions of the larynx in 34 cases and in 7 cases, squamous cell carcinoma Immunohistochemical study was performed using antibodies against the cell surface markers S-100, HLA-DR, CD20, CD45 RO, CD45 RA, and Lag. Typical dendritic cell distributions of the immunostained specimens were photographed and measured on a quantitative basis. The medical histories of the patients were then analyzed retrospectively. RESULTS: HLA-DR+ cells could be detected in 14 of 16 cases in mild dysplastic lesions. The infiltration of the dysplastic lesions was sparse compared to cases with higher-graded dysplastic lesions. The distribution patterns of the dendritic cells in specimens with severe dysplastic lesions, but squamous cell carcinoma were extremely similar and markedly different from those in grades I and II specimens. Memory T lymphocytes (CD45 RO+) were detected more often in the group with severe dysplastic lesions (8 of 9 cases) than in the group with squamous cell carcinoma (3 of 8 cases). The inverse became evident for CD20 and CD45 RA immunolabeling. CONCLUSIONS: Few dendritic cells were found in the precancerous lesions. This may suggest that these early lesions (grades I and H) are not efficiently monitored by the immune system. Therefore they may develop into carcinomas unimpaired by cytotoxic T cells. As the degree of malignancy rises (grade III), more dendritic cells infiltrate the tumor.

[Value of a nutrition score in patients with advanced carcinomas in the area of the head and neck]. / Stellenwert eines Ernährungsscores bei Patienten mit fortgeschrittenen Karzinomen im Kopf-Hals-Bereich.

BACKGROUND AND OBJECTIVE: Patients with advanced head and neck cancer often suffer from malnutrition even before the start of therapy. Hence, the demand for nutritional support increases particularly before and during radiochemotherapy. Though nutritional therapy has been shown to substantially improve individual outcome, neither the criteria for patient candidacy nor the indications for therapeutic intervention have been established. We performed a retrospective analysis to determine the indications for nutritional support and < 0 evaluate the benefits of measures actually taken against malnutrition before and during radiochemotherapy as well as perioperatively. PATIENTS/METHODS: Data taken from a prospective study for the evaluation of oral mucositis during radiochemotherapy was analysed retrospectively. To calculate the indication for nutritional support, a nutritional scoring system (Hackl) was employed for the first time, which contained biochemical and anthropometric parameters as well as the period of starvation. The results were then compared to a nutritional support program implemented by the subjective examinations of the attending physician. RESULTS: Changes in body weight and body mass index (BMI) remained the most impressive parameters. Catabolic metabolism developed preoperatively and a significant loss of whole-body protein followed surgical therapy. Clinically, the results of the nutritional score correlated with the observation of malnutrition. Furthermore, our findings suggest that nutritional therapy was commonly delayed until late in the clinical course. CONCLUSION: The results indicate the necessity of objective and reproducible diagnosis and control of malnutrition. The scoring system used may provide a useful and yet simple tool for assessing individual indications for timely nutritional support.

Computer-aided surgery in the petrous bone.

OBJECTIVE: We demonstrate that computer-assisted frameless stereotactic navigation with the ISG/ELEKTA Viewing Wand system in the petrous bone is routinely possible with sufficient application accuracy. METHODS: High-resolution computed tomography imaging is done with a dedicated structure attached to the mouthpiece of the Vogele-Bale-Hohner (VBH) head holder, an integral part of our intraoperative patient fixation. The patient image registration can be reliably performed before surgery in an unsterile environment with the registration structure of the mouthpiece. For intraoperative navigation either the position-sensitive articulated arm or the optical three-dimensional digitizer of the ISG/ELEKTA system is used. RESULTS: In the operations of the petrous bone performed so far, i.e., mastoidectomy, cholesteatoma surgery, and lateral skull base revision surgery, the clinical value of three-dimensional navigation was clearly demonstrated with an application accuracy, constant throughout surgery, mostly limited only by the resolution of the computed tomography.

Bone density measurements of the paranasal sinuses on plastinated whole-organ sections: anatomic data to prevent complications in endoscopic sinus surgery.

OBJECTIVE/HYPOTHESIS: Although anatomic data regarding the gross anatomy of the paranasal sinuses are available, severe complications of endonasal sinus surgery (ESS) are frequently reported. To understand and to avoid these complications, density of bony walls of the paranasal sinuses were studied in this report. Special attention was given to the analysis of the bone density in regions where minor and major complications occur in ESS. METHODS: Thirty cadaver heads were embedded in epoxy resin. The plastic blocks were sectioned with a diamond-coated wire saw into 1.0-mm thick, parallel slices in axial, coronal, and sagittal planes for 10 specimens each. The slices were x-rayed and scanned with a computerized image analyzing system. For each specimen the bone density in 12 regions of interest was measured. RESULTS: Besides the macroscopic examination of the plastinated specimens, a bone density analysis based on x-ray films is presented. Lowest bone density was found at the lateral wall of the sphenoid sinus (3.31 +/- 0.99 mm aluminum [Al]); highest density was measured at the roof of the sphenoid sinus (12.91 +/- 1.75 mm Al). Overall bone density in female specimens was 0.41 mm Al (mean) lower than in male specimens. CONCLUSIONS: This study is the first to use plastinated whole-organ serial sections and bone density images for the analysis of potential complications in ESS. The illustration of regions with minor and major bone density of the paranasal sinuses and the ethmoid floor as presented in this study may help the novice sinus surgeon to minimize the risks of ESS and to avoid severe complications.

Three-dimensional navigation in otorhinolaryngological surgery with the viewing wand.

We report our experiences with the ISG Viewing Wand intraoperative 3-dimensional navigation device in endonasal endoscopic procedures of the paranasal sinuses, anterior skull base, and petrous bone. In the last 12 months we have routinely used the wand in 90 patients for treatment of polyposis nasi, for biopsies and removal of tumors in the nasal cavity and at the frontal skull base, for endocrine ophthalmopathy, and in 1 case for cholesteatoma. We present our computed tomography, magnetic resonance imaging, and clinical protocols that allow a precise routine use of the Viewing Wand. In all cases, the system was extremely helpful for intraoperative localization and helped to optimize surgery.