Automated surgery planning for an obstructed nose by combining computational fluid dynamics with reinforcement learning.

Septoplasty and turbinectomy are among the most common interventions in the field of rhinology. Their constantly debated success rates and the lack of quantitative flow data of the entire nasal airway for planning the surgery necessitate methodological improvement. Thus, physics-based surgery planning is highly desirable. In this work, a novel and accurate method is developed to enhance surgery planning by physical aspects of respiration, i.e., to plan anti-obstructive surgery, for the first time a reinforcement learning algorithm is combined with large-scale computational fluid dynamics simulations. The method is integrated into an automated pipeline based on computed tomography imaging. The proposed surgical intervention is compared to a surgeon's initial plan, or the maximum possible intervention, which allows the quantitative evaluation of the intended surgery. Two criteria are considered: (i) the capability to supply the nasal airway with air expressed by the pressure loss and (ii) the capability to heat incoming air represented by the temperature increase. For a test patient suffering from a deviated septum near the nostrils and a bony spur further downstream, the method recommends surgical interventions exactly at these locations. For equal weights on the two criteria (i) and (ii), the algorithm proposes a slightly weaker correction of the deviated septum at the first location, compared to the surgeon's plan. At the second location, the algorithm proposes to keep the bony spur. For a larger weight on criterion (i), the algorithm tends to widen the nasal passage by removing the bony spur. For a larger weight on criterion (ii), the algorithm's suggestion approaches the pre-surgical state with narrowed channels that favor heat transfer. A second patient is investigated that suffers from enlarged turbinates in the left nasal passage. For equal weights on the two criteria (i) and (ii), the algorithm proposes a nearly complete removal of the inferior turbinate, and a moderate reduction of the middle turbinate. An increased weight on criterion (i) leads to an additional reduction of the middle turbinate, and a larger weight on criterion (ii) yields a solution with only slight reductions of both turbinates, i.e., focusing on a sufficient heat exchange between incoming air and the air-nose interface. The proposed method has the potential to improve the success rates of the aforementioned surgeries and can be extended to further biomedical flows.

[Neuroendocrine tumors in head and neck]. / Neuroendokrine Tumoren im Kopf-, Halsbereich.

INTRODUCTION: NETs are benign or malign tumors, which originate from cells of the endocrine (hormonal) and nervous systems. 0,5-2 % of the neoplasms are neuroendocrine tumors, which are mostly located in the gastrointestinal or bronchopulmonal tract. Die incidence is about 9000/100000. 1% of the head and neck tumors are NET. This study evaluates NETs with different locations, its therapy and outcome. METHODS: 14 patients with a neuroendocrine tumor of the head and neck between 2010 and 2017 were evaluated. 8 patients underwent an operation and adjuvant radiochemotherapy (RCT). Five patients had a prim. RCT with curative intention. One patient had a palliative chemotherapy because of the progress after the radiochemotherapy. RESULTS: The locations of the tumors are the larynx (n=7), parotid gland (n=2) and the paranasal sinuses (n=5). A resection in sano (R0) could be reached in 6 of 8 cases. The average survival rate was 19±6 months. 2 tumor recurrences occurred out of 14 patients. 1 patient died after 7 months und 1 patient is without recurrence after 32 months. 2 patients had no benefit of the combined radiochemotherapy and died after 6 and 13 months. Die overall survival depends on the stage and the R0 resection of the tumors. The R0 resection is better in comparison to the prim. according to the overall survival time. CONCLUSION: Patients with NET of the head and neck have to be treated in specialized cancer centers. Each patient should receive an individual therapy depending on localization and histopathological findings.

Olfactory functioning in adults with Tourette syndrome.

Tourette syndrome is a chronic tic disorder characterized by motor and vocal tics. Comorbidities such as attention deficit hyperactivity disorder and obsessive compulsive disorder can be found. The overlap between neuroanatomical regions and neurotransmitter systems in the olfactory system and the pathophysiology of Tourette syndrome let us hypothesize altered olfactory performance in Tourette syndrome. The main objective of this study was to systematically assess olfactory functioning in subjects with Tourette syndrome and to compare it to healthy controls. We assessed 28 adults with Tourette syndrome (age 33.1±9.4 years, disease duration 23.7±9.7 years) and 28 healthy controls (age 32.9±9.0 years) matched in regard to age, sex, education and smoking habits. The "Sniffin Sticks" test battery was applied to assess odor threshold, discrimination, and identification. Additionally, the combined score of the odor threshold test, the odor discrimination test and the odor identification test of the "Sniffin Sticks" test battery was calculated. Although it was not the primary aim of this study, we assessed whether tics and comorbidity could contribute to olfactory alterations in adults with Tourette syndrome. Therefore, clinical scores were used to assess severity of tics and co-morbidity such as attention deficit hyperactivity disorder, obsessive compulsive disorder, anxiety and depression in subjects with Tourette syndrome. Pathology of the nasal cavities was excluded with rhinoendoscopy. Independent sample t-tests were applied to compare performance in olfactory tests. In the case of statistically significant differences (critical p-value: 0.05), multiple linear regression analysis was carried out to explore whether tic severity, social impairment, co-morbidity or medical treatment had an impact on the differences found. Descriptive values are reported as mean ± standard deviation. Tourette syndrome subjects showed lower combined scores (Tourette syndrome subjects 31.9 ± 5.1 versus healthy controls 35.0 ± 3.1; p = 0.007), odor identification scores (Tourette syndrome subjects 12.4 ± 2.0 versus healthy controls 13.7 ± 1.4; p = 0.008) and odor discrimination scores (Tourette syndrome subjects 12.1 ± 2.1 versus healthy controls 13.2 ± 1.6; p = 0.041) in comparison to healthy subjects, while there was no difference in odor threshold (Tourette syndrome subjects 7.3 ± 2.7 versus healthy controls 8.1 ± 2.2; p = 0.22). Seven out of 28 Tourette syndrome subjects (25%) scored in the range of the age- and sex-dependent combined score for hyposmia, while two of 28 healthy controls (7%) had a similar low combined score. None of the participants were found to have functional anosmia. Multiple linear regression analyses suggest that social impairment may a predictor for low combined score and odor identification score in Tourette syndrome subjects (p = 0.003). Compared to healthy controls, altered olfaction in adults with Tourette syndrome was found in this study. Normal odor threshold level but lower scores at tasks involving supra-threshold odor concentrations point towards a central-nervous alteration in the processing of olfactory information in Tourette syndrome.

Cinnarizine and dimenhydrinate in the treatment of vertigo in medical practice.

The efficacy and safety of the fixed combination of cinnarizine 20 mg and dimenhydrinate 40 mg in the treatment of vertigo of various origins have been investigated in a prospective, noninterventional study involving private practices throughout Germany. A total of 1275 patients with an average age of 61.2 years participated in the study. The vertigo symptoms, measured by a validated mean vertigo score (primary efficacy endpoint) improved by 61 % in the course of the observational period (median: 6 weeks). Concomitant symptoms frequently associated with vertigo such as nausea, vomiting and tinnitus were also markedly reduced by 84, 85 and 51 %, respectively. Overall efficacy has been rated by the physicians as 'very much improved' or 'much improved' in 95 % of the patients. A total of 47 patients (3.7 %) reported 51 adverse drug reactions (all nonserious). The results indicate a good tolerability and efficacy of the fixed combination of cinnarizine and dimenhydrinate in the treatment of vertigo in daily medical practice, which is in line with previous findings of numerous interventional, randomised, double-blind, controlled clinical trials.

Vestibular rehabilitation using the Nintendo® Wii Balance Board -- a user-friendly alternative for central nervous compensation.

CONCLUSION: The Nintendo® Wii Balance Board is a cost-effective and user-friendly alternative to other popular frequently used systems that aid vestibular compensation, particularly in elderly patients. In addition, further treatment in the home environment is possible. OBJECTIVE: This cohort study was designed to investigate the impact of the Nintendo® Wii Balance Board as a visual compensation device after acute vestibular neuritis. METHODS: Subjects were randomly assigned to one of two treatment groups. Group A (n = 37) performed customized exercises with the Nintendo® Wii Balance Board. Group B (n = 34) performed only two elected exercises as a control group for comparison of the results. Both groups underwent additive therapy with steroids (intravenous) in decreasing doses (250 mg decreasing to 25 mg over 10 days). The Sensory Organization Test (SOT), Dizziness Handicap Inventory (DHI), Vertigo Symptom Scale (VSS), and Tinneti questionnaire were evaluated immediately before treatment (baseline), at the end of treatment, i.e. at day 5, and after 10 weeks. RESULTS: The early use of a visual feedback system in the context of the balance training supports the central nervous vestibular compensation after peripheral labyrinthine disorders. Patients in group B (without training) required a longer in-patient stay (average 2.4 days, SD 0.4) compared with patients following early Wii rehabilitation. The absence of nystagmus under Frenzel's goggles in group A was observed 2.1 days (SD 0.5) earlier than in group B. Group A showed significantly better results in the SOT, DHI, VSS, and Tinneti questionnaire at all time points measured (p < 0.05).

The future of medical diagnostics: review paper.

While histopathology of excised tissue remains the gold standard for diagnosis, several new, non-invasive diagnostic techniques are being developed. They rely on physical and biochemical changes that precede and mirror malignant change within tissue. The basic principle involves simple optical techniques of tissue interrogation. Their accuracy, expressed as sensitivity and specificity, are reported in a number of studies suggests that they have a potential for cost effective, real-time, in situ diagnosis.We review the Third Scientific Meeting of the Head and Neck Optical Diagnostics Society held in Congress Innsbruck, Innsbruck, Austria on the 11th May 2011. For the first time the HNODS Annual Scientific Meeting was held in association with the International Photodynamic Association (IPA) and the European Platform for Photodynamic Medicine (EPPM). The aim was to enhance the interdisciplinary aspects of optical diagnostics and other photodynamic applications. The meeting included 2 sections: oral communication sessions running in parallel to the IPA programme and poster presentation sessions combined with the IPA and EPPM posters sessions.

At the frontiers of surgery: review.

The complete surgical removal of disease is a desirable outcome particularly in oncology. Unfortunately much disease is microscopic and difficult to detect causing a liability to recurrence and worsened overall prognosis with attendant costs in terms of morbidity and mortality. It is hoped that by advances in optical diagnostic technology we could better define our surgical margin and so increase the rate of truly negative margins on the one hand and on the other hand to take out only the necessary amount of tissue and leave more unaffected non-diseased areas so preserving function of vital structures. The task has not been easy but progress is being made as exemplified by the presentations at the 2nd Scientific Meeting of the Head and Neck Optical Diagnostics Society (HNODS) in San Francisco in January 2010. We review the salient advances in the field and propose further directions of investigation.

The internal dimensions of the cochlear scalae with special reference to cochlear electrode insertion trauma.

HYPOTHESIS: To investigate the intracochlear micromorphology with regard to frequent patterns of cochlear electrode insertion trauma. OBJECTIVE: Cochlear implantation is a widely accepted treatment for deafness and high-grade sensorineural hearing loss. Although the device and the implantation methods are continuously optimized, damage of intracochlear structures due to electrode insertion is a frequent finding in temporal bone studies. Reduction of insertional trauma is important for the preservation of residual hearing and on the background of increasing numbers of cochlear implant recipients. MATERIALS AND METHODS: This study was performed with histologic specimens from the "Wittmaack temporal bone collection" (Hamburg, Germany) to examine the diameters of intracochlear spaces and to correlate the micromorphology of cochlear ducts to frequent patterns of intracochlear insertion trauma. RESULTS: The diameter of the scala tympani decreases by approximately 300 microm during the ascending part of the basal turn. In this region, the intersegmental decrease exceeds the assumed linear diameter decrease significantly (p < or = 0.001). The regression of the cross-sectional diameter is accompanied by a shift of the spiral osseous lamina toward the scala tympani and by narrowing of the bony capsule of the cochlea. CONCLUSION: Various attempts have been made to evaluate the dimensions of the cochlea related to cochlear implantation. Little attention was paid to the distinct narrowing of the scala tympani in the region of the ascending part of the cochlear duct, although from the literature, it is known that electrode insertion trauma frequently occurs here. Individual variations of the cochlear micromorphology may additionally contribute to the failure of preformed electrode arrays, but the challenge of guiding the electrode array around the first bend of the cochlear turn, that is, the pars ascendens, is obviously impaired by the interindividually constant narrowing in this area. Therefore, this finding may have implications on the development of electrode designs and insertion methods.

On the number of turns in human cochleae.

OBJECTIVE: The number of human cochlear turns is generally accepted being 2 1/2, although cases with up to 2 3/4 or even 3 turns are known from literature. This study was performed to evaluate the actual number of cochlear turns and its variance. METHODS: Histologic temporal bone series from the "Wittmaack temporal bone collection" (Hamburg, Germany) were examined, and the number of scala media segments was counted using the midmodiolar sections. These data were evaluated in reference to the cochlear spiral to obtain the number of cochlear turns. RESULTS: Sixty-five percent of the investigated specimens had more than 2 1/2 cochlear turns, of which, 11% had more than 2 3/4 turns. CONCLUSION: The number of human cochlear turns shows a higher variance than is represented in literature. Cases with up to 3 turns can be regarded as upper limit of the normal range. This finding may carry further implications for cochlear implantation to focus on the development of individually shaped electrode carriers and stimulation strategies.

Free-text data entry by speech recognition software and its impact on clinical routine.

We conducted a study to evaluate speech recognition software in an otorhinolaryngology unit and to assess its impact on productivity prior to general implementation. Current speech recognition software (IBM ViaVoice, version 10) was implemented on a personal computer with a 2-GHz central processing unit, 256 MB of RAM, and a 30-GB hard disk drive, with and without add-on professional vocabulary for otorhinolaryngology. This vocabulary was added by the automated analysis of an additional 12,257 documents from our department. We compared the word recognition error rates for three different text types and determined their impact on the amount of surgeon's time that was invested in the production of an error-free document. Although error rates without any professional vocabulary database were rather high (operation reports: 38.72%; consultation notes: 27.77%), the patient information was edited with a satisfactory result (10.65%). Best results were obtained with the specialty-related vocabulary database added by the analysis of our own documents (operation reports: 5.45%; consultation notes: 5.21%). An increase in productivity compared with that of conventional transcription was found at an error rate of less than 16%.

Morphological effects of nanosecond- and femtosecond-pulsed laser ablation on human middle ear ossicles.

We evaluate the feasibility of nanosecond-pulsed and femtosecond-pulsed lasers for otologic surgery. The outcome parameters are cutting precision (in micrometers), ablation rate (in micrometers per second), scanning speed (in millimeters per second), and morphological effects on human middle ear ossicles. We examine single-spot ablations by a nanosecond-pulsed, frequency-tripled Nd:YAG laser (355 nm, beam diameter 10 microm, pulse rate 2 kHz, power 250 mW) on isolated human mallei. A similar system (355 nm, beam diameter 20 microm, pulse rate 10 kHz, power 160-1500 mW) and a femtosecond-pulsed CrLi:SAF-Laser (850 nm, pulse duration 100 fs, pulse energy 40 microJ, beam diameter 36 microm, pulse rate 1 kHz) are coupled to a scanner to perform bone surface ablation over a defined area. In our setups 1 and 2, marginal carbonization is visible in all single-spot ablations of 1-s exposures and longer: With an exposure time of 0.5 s, precise cutting margins without carbonization are observed. Cooling with saline solution result is in no carbonization at 1500 mW and a scan speed of 500 mms. Our third setup shows no carbonization but greater cutting precision, although the ablation volume is lower. Nanosecond- and femtosecond-pulsed laser systems bear the potential to increase cutting precision in otologic surgery.

Speech perception in elderly patients following cochlear implantation.

CONCLUSIONS: Elderly patients benefit from cochlear implantation in terms of speech perception and quality of life. Age alone should be no contraindication for implantation. OBJECTIVE: There have been concerns whether elderly patients may perform poorly after cochlear implantation due to degenerative processes in the central and peripheral auditory systems. The purpose of this study was to analyze the benefits of cochlear implantation in elderly patients in comparison to younger recipients. MATERIAL AND METHODS: We examined 26 postlingually deafened adults aged > 65 years who received a cochlear implant at our center regarding preoperative findings, comorbidities, postoperative complications and quality of life. Speech perception was assessed by means of multi- and monosyllabic word recognition and compared to the results obtained by younger patients. RESULTS: The surgical procedure was well tolerated by all patients without notable perioperative complications. In terms of speech perception, no significant differences between the elderly patients and younger recipients were noted. All patients found that cochlear implantation had a positive impact on their quality of life.

Idiopathic sudden sensorineural hearing loss in children.

OBJECTIVE: Although idiopathic sudden sensorineural hearing loss (ISSHL) is a frequent disease in adults, less is known about incidence and treatment of ISSHL in children. METHOD: A retrospective chart analysis was performed to evaluate the frequency of ISSHL in children aged under 18 years between 2000 and 2003, who were treated in our department. Children received prednisolone intravenously at an initial dose of 3mg/kg bodyweight. Prednisolone dose was reduced to half every second day. The medication was given for a maximum of 14 days or finished 2 days after the hearing normalized in pure-tone audiometry. The follow-up was continued between 3 and 14 months. RESULTS: The complete recovery rate was 57%, and the partial recovery was 36%. Initial hearing loss of 50dB and more was predictive for poor outcome in children (p=0.028). Presence of tinnitus was without relevance for the outcome. The incidence of ISSHL in the local area of about 250,000 inhabitants was 1/10,000 in children. CONCLUSION: ISSHL seems to be a less frequent disease in children than in adults. Severe initial hearing loss is coupled with poor outcome. Under treatment with prednisolone hearing improvement was found in 13 of 14 patients.

Subclassification of vestibular disorders by means of statistical analysis in caloric labyrinth testing.

OBJECTIVE: In the past, various attempts were made to perform a quantitative analysis of nystagmographic findings but their diagnostic value was limited. Therefore, the authors present a multivariate analysis of nystagmus findings with the aim of increasing the precision of diagnostic differentiation in cases of vestibular dysfunction. MATERIAL AND METHODS: A group of 387 patients and 40 healthy volunteers were examined over a 14-month period using electronystagmography after stimulation by bithermal, bilateral irrigation of the labyrinth. Amplitude, slow-phase velocity, frequency and directional preponderance were evaluated. RESULTS: No defined normal values for caloric nystagmus parameters could be obtained. However, by using the Mann Whitney U-test and logistic regression analysis a differentiation between pathological and healthy findings as well as between central and peripheral vestibular disorders and even between distinct vestibular disease entities is possible. Using these methods, the nystagmus amplitude was found to be the strongest discriminating parameter. Therefore, sole assessment of nystagmographic findings by selective calculation of the nystagmus slow-phase velocity falls short of the potential offered by electronystagmographic registration. CONCLUSION: For daily clinical routine, counting nystagmus beats leads to the same diagnostic precision as the analysis of slow-phase velocities. In contrast, multivariate analysis of several nystagmus parameters can distinguish between distinct diseases with fairly high precision. This stepwise analysis of nystagmographic data could create the basis for an expert-system tool in the near future.

Colour texture analysis for quantitative laryngoscopy.

OBJECTIVE: Whilst considerable progress has been made in enhancing the quality of indirect laryngoscopy and image processing, the evaluation of clinical findings is still based on the clinician's judgement. The aim of this paper was to examine the feasibility of an objective computer-based method for evaluating laryngeal disease. MATERIAL AND METHODS: Digitally recorded images obtained by 90 degree- and 70 degree-angled indirect rod laryngoscopy using standardized white balance values were made of 16 patients and 19 healthy subjects. The digital images were evaluated manually by the clinician based on a standardized questionnaire, and suspect lesions were marked and classified on the image. Following colour separation, normal vocal cord areas as well as suspect lesions were analyzed automatically using co-occurrence matrices, which compare colour differences between neighbouring pixels over a predefined distance. RESULTS: Whilst colour histograms did not provide sufficient information for distinguishing between healthy and diseased tissues, consideration of the blue content of neighbouring pixels enabled a correct classification in 81.4% of cases. If all colour channels (red, green and blue) were regarded simultaneously, the best classification correctness obtained was 77.1%. CONCLUSIONS: Although only a very basic classification differentiating between healthy and diseased tissue was attempted, the results showed progress compared to grey-scale histograms, which have been evaluated before. The results document a first step towards an objective, machine-based classification of laryngeal images, which could provide the basis for further development of an expert system for use in indirect laryngoscopy.

Long-term follow-up after laser-induced endotracheal fire.

The objective of this presentation is to outline long-term complications and their management in contrast to acute measures after endotracheal laser-induced fire. This case focuses on a 56-year-old patient in whom an endotracheal fire occurred during CO2 laser surgery. Despite local swelling and evidence of acute lung injury, the patient was extubated the following day under single-shot cortisone and inhalation of dispersed adrenaline under assisted spontaneous breathing. Wound healing was assessed by regular flexible bronchoscopy and spirometry. Fourteen weeks after uneventful recovery, the patient presented with acute inspiratory stridor, related to a tracheal stenosis 2.5 cm distal to the glottic level. After tracheal end-to-end anastomosis, further follow-up was uneventful. Early extubation under ITU conditions avoided the need for tracheostomy and its sequelae. However, tracheal stenosis did not become apparent before week 14. While in acute management of laser-induced endotracheal fire a conservative approach was established successfully, the risk of further long-term complications implies the need for a prolonged follow-up regime even in cases of less extensive burns.