[Intracranial hemorrhage after sinus venous thrombosis during cochlear implantation : A case report]. / Intrakranielle Blutung nach Sinusvenenthrombose bei Cochleaimplantation : Ein Fallbericht.

Cochlear implantation is a safe surgical procedure with low complication rates. In particular, intracranial complications are rare. We present the case of a patient with difficult anatomical relations, which led to injury of the sigmoid sinus during cochlear implantation. Thrombosis and intracerebral hemorrhage followed. The diagnostic steps and treatment of these complications are explained in this case report.

The Bonebridge Bone Conduction Hearing Implant: indication criteria, surgery and a systematic review of the literature.

BACKGROUND: Hearing aids and implants employing bone conduction (BC) stimulation have a long tradition in the treatment of conductive or mixed hearing loss, with their indications being extended in the 2000s to include single-sided deafness (SSD). Existing percutaneous bone conduction implants (BCI) provide significant audiological gain but are associated with a high rate of complications. This has led to the development of passive transcutaneous BCIs; however, audiological benefit may be compromised. An active transcutaneous BCI, the Bonebridge, was recently introduced and first implanted in 2011 as part of a clinical trial. OBJECTIVE OF REVIEW: To introduce and assess the safety and effectiveness of the Bonebridge for individuals with conductive or mixed hearing loss, and SSD. TYPE OF REVIEW: Systematic review. SEARCH STRATEGY: The Cochrane Library, PubMed and OVIDSP (MEDLINE) and EMBASE were searched to identify papers on the Bonebridge published as of June 2014. No exclusion criteria were set on publication language, study design or reported outcomes. The literature found was supplemented by presentations from relevant conferences. EVALUATION METHOD: Study selection, data extraction and study quality assessment were carried out by a single reviewer with any uncertainties resolved with consulting a second reviewer. Studies were synthesised narratively and results were tabulated. RESULTS: A total of 29 studies, 17 published and 12 presentations, were identified. The highest quality evidence was from three single-arm trials. In those assessing the safety of implantation, 6 of 117 patients experienced a minor adverse event with superficial revision surgery being required in one case. Studies demonstrated improved hearing thresholds and speech recognition with the Bonebridge when compared to no aiding in adults and children with either type of hearing loss. This was reflected in high device satisfaction rates. Data collected in the second year of device use further suggest the benefit to remain constant. CONCLUSION: The transcutaneous BCI system Bonebridge provides a valuable and stable audiological benefit to patients suffering from conductive or mixed hearing loss and SSD. With its active transcutaneous design, the Bonebridge offers a lower complication rate to percutaneous systems and higher and more reliable hearing gain compared to other transcutaneous or percutaneous systems. Moreover, the fast activation of the implant system enables the recipient of the system to benefit in a short time frame postoperatively from the intervention.

Postoperative changes in telemetry measurements after cochlear implantation and its impact on early activation.

INTRODUCTION: Cochlear implantation is a clinically routine treatment for patients with severe sensorineural hearing loss for over 20 years. Up to now, the general recommendation for speech processor activation was 4 weeks after cochlear implantation. The aim of this study was to determine whether activation is possible at <4 weeks postop and to show the postoperative change in telemetry over time. MATERIAL AND METHODS: The study was retrospectively carried out at the Karl Landsteiner University Hospital St. Pölten, Austria. Patients who routinely received a CI between January and August 2013 were included in this study. Two weeks after the surgery clinical complications, the ability to wear the audio processor and the impedance values were analysed. RESULTS: Forty-five patients were included in this study. Forty patients were examined at the first postoperative visit, scheduled 2 weeks after the surgery. In nine cases, a mild wound-healing complication occurred; just in one patient, the activation could not carry out immediately. There were no statistically significant differences between the intraoperative, the 2- and 6-week postop impedance measurements for each channel. DISCUSSION: We used the minimally invasive approach and soft implantation technique in all of our patients and believe this to have been a major reason that earlier activation was possible. With this technique, you can reduce the wound-healing process, which makes it possible for the wound to heal fully and for the patient to wear the sound processor over the wound without problems. We found out that telemetry is not a predictor for the time of activation. CONCLUSION: Based on the results in this study, an earlier activation can be recommended. This will shorten the time the patient needs to wait following cochlear implantation, and rehabilitation can begin sooner.

[Listening effort with cochlear implants: Unilateral versus bilateral use]. / Höranstrengung bei Cochlea-Implantaten: Einseitige versus beidseitige Versorgung.

AIM: The influence of bilateral cochlear implants (CI) and unilateral CI on the self-reported listening effort in standardized situations is being assessed. SAMPLE AND METHODS: The sample consisted of 34 bilateral and 38 unilateral adult CI users. Unilateral CI users had at least severe hearing loss in the non-implanted ear and had been fitted with a hearing aid. The listening effort has been defined as a subjectively perceived effort in understanding a speaker. Patients were administered a customized questionnaire containing nine examples of listening situations with different demands. The listening effort expended in each situation had to be rated on a six-step scale. Answers were analyzed using repeated measures ANOVA, including the factors "level of background noise," "listening duration," and the covariates "patient age" and "time since CI implantation." RESULTS: Only the factors "level of background noise" and "listening duration" were significant (p = 0.024 and p = 0.001 respectively). Unilateral versus bilateral CI was not significant (p = 0.17). Nevertheless, bilateral CI users reported a lower degree of listening effort than unilateral users in all of the nine situations asked about in the questionnaire (binomial test: p = 0.002). DISCUSSION: We conclude that bilateral CI use has some effect on reducing listening effort, but compared with unilateral use the effect is possibly not very great.

Comparison of artefact reduction possibilities with the new active transcutaneous bone conduction implant (Bonebridge).

OBJECTIVE: This study aimed to evaluate the possibilities of artefact reduction using different anatomical implant positions with the Bonebridge bone-conduction hearing implant 602 for a patient with an acoustic neuroma requiring regular diagnostic magnetic resonance imaging of the tumour position. METHOD: Three implant positions and magnetic resonance imaging examinations with and without customised sequences for metal artefact suppression were investigated. The diagnostic usefulness was rated by a radiologist (qualitative evaluation), and the relation between the area of artefact and the total head area was calculated (quantitative evaluation). RESULTS: Following the qualitative analysis, the radiologist rated the superior to middle fossa implant placement significantly better for diagnostic purposes, which is in agreement with the calculated artefact ratio (p < 0.0001). The customised slice-encoding metal artifact correction view-angle tilting metal artifact reduction technique sequences significantly decreased the relative artefact area between 5.13 per cent and 25.02 per cent. The smallest mean artefact diameter was found for the superior to middle fossa position with 6.80 ± 1.30 cm (range: 5.42-9.74 cm; reduction of 18.65 per cent). CONCLUSION: The application of artefact reduction sequencing and special anatomical implant positioning allows regular magnetic resonance imaging in patients with the bone-conduction hearing implant 602 without sacrificing diagnostic imaging quality for tumour diagnosis.

[The active middle ear implant for the rehabilitation of sensorineural, mixed and conductive hearing losses]. / Das aktive Mittelohrimplantat in der Rehabilitation von sensorineuralen, kombinierten und Schallleitungs-Hörstörungen.

Active middle ear implants, such as the Vibrant Soundbridge, are used as an important part in the rehabilitation of sensorineural, conductive hearing, or mixed hearing loss. The attachment of the Vibrant Soundbridge at the round window and the usage of the Vibroplasty couplers strongly expanded the application of the Vibrant Soundbridge.The Vibrant Soundbridge is developed for patients who have an intolerance to hearing aids and a moderate to profound sensorineural hearing loss. The VSB also provides an optimal solution for patients with failed middle ear reconstructions or patients with atresia. To capture the improvement with the VSB Implant with different hearing losses a literature analysis was conducted. The functional gain was analyzed for 107 patients with conductive hearing loss and for 214 patients with sensorineural hearing loss out of 14 studies.Patients with conductive and mixed hearing loss resulted in a functional gain from 30 to 58 dB with the VSB. Patients with a pure sensorineural hearing loss showed a functional gain of 23-30 dB. The VSB bone conduction threshold shift was analyzed for all studies conducted in the years between 2000 and 2009. In 11 of the 16 studies there was no significant (p=0.05) change found. In 5 studies, the pre- to post-surgical bone conduction threshold shift was less than 10 dB. None of these studies measured a threshold shift of more than 10 dB.The flexible attachment at either the long process of the incus with sensorineural hearing loss, with an conductive hearing loss at the round window or the use of Vibroplasty couplers at the oval window, head of the stapes or round window makes the VSB an extremely versatile instrument. If patients can't wear conventional hearing aids, had failed middle ear reconstructions or atresia the VSB presents, due to the significant hearing improvement in any type of hearing loss, an ideal solution.

Current trends in treating hearing loss in elderly people: a review of the technology and treatment options - a mini-review.

BACKGROUND: According to the World Health Organization (WHO), by 2025 there will be approximately 1.2 billion people in the world over the age of 60, which marks a shift in world population to a greater proportion of older people. An estimated 70-80% of adults between 65 and 75 years of age suffer from presbycusis, or age-related, bilateral sensorineural hearing loss (HL) in the high frequencies. Presbycusis is correlated with decreased quality of life (QoL) and depression and according to WHO, is a leading cause of years lived with disability in the adult years. OBJECTIVE: The purpose of the current study was to review the body of literature on treatment options and considerations for the elderly population, as there is a variety of audio-technology available today to treat presbycusis. METHODS: A PubMed literature search was conducted using the keywords 'presbycusis/presbyacusis/geriatric AND hearing aids/cochlear implants/electric acoustic stimulation/middle ear implants' and 'elderly AND cochlear implants'. References were also mined from papers found. RESULTS: 431 articles were considered in this review of treatment options for elderly patients suffering from presbycusis. CONCLUSION: Hearing aids and cochlear implants (CIs) are the most commonly used devices for treating mild-severe presbycusis. Reported outcomes with hearing aids indicate they are an effective method for treating mild-moderate HL in cases where the patient is appropriately fitted and is willing, motivated, and able to use the device. Depending on the type and severity of the HL and the specific needs of the patient, electric-acoustic stimulation and active middle ear implants may also be appropriate solutions for treating presbycusis. Finally, very positive QoL and speech perception outcomes have been documented in treating severe-profound presbycusis with CIs. In some studies, QoL outcomes have even exceeded expectations of elderly patients.

68Ga-DOTATOC PET/CT in the localization of metastatic extra-adrenal paraganglioma and pheochromocytoma compared with 18F-DOPA PET/CT. / Comparación entre la PET/TC con 18F-DOPA y la PET/TC con 68Ga-DOTATOC para la localización del paraganglioma maligno extra-adrenal y el feocromocitoma.

OBJECTIVE: 18F-Fluoro-L-dihydroxyphenylalanine (18F-DOPA) PET offers high sensitivity and specificity in the imaging of non-malignant extra-adrenal paraganglioma (PGL) and pheochromocytoma (PHEO) but lower sensitivity in metastatic disease. These tumours are of neuroendocrine origin and can be detected by 68Ga-DOTA-Tyr3-octreotide (68Ga-DOTA-TOC) PET. Therefore, we compared 68Ga-DOTA-TOC and 18F-DOPA as radiolabels for PET/CT imaging for the diagnosis of metastatic extra-adrenal PGL and PHEO. Combined cross-sectional imaging was the reference standard. METHODS: A total of 6 men and 4 women (age range 22-72 years) with anatomical and/or histologically proven metastatic PGL and PHEO were included in this study. Of these patients, 2 male patients suffered from PHEO, while the remaining 8 patients were diagnosed as metastatic extra-adrenal PGL disease. Comparative evaluation included morphological imaging with CT and functional imaging with 68Ga-DOTA-TOC and 18F-DOPA PET. The imaging results were analyzed on a per-lesion basis. The maximum standardized uptake value (SUVmax) of each functional imaging modality in concordant tumour lesions was measured. RESULTS: Compared with anatomical imaging, the per-lesion detection rate of 68Ga-DOTA-TOC was 100% (McNemar, P<0.01), and that of 18F-DOPA PET was 82.3% (McNemar, P<0.8) in metastatic extra-adrenal PGL and PHEO. Overall, 68Ga-DOTA-TOC PET identified 67 lesions; anatomical imaging identified 62 lesions, and 18F-DOPA PET identified 56 lesions. The SUVmax (mean±SD) of all concordant lesions was 29.3±19.9 for 68Ga-DOTA-TOC PET and 12.3±9.1 for 18F-DOPA PET (Mann-Whitney U test, P<0.0001). CONCLUSION: 68Ga-DOTA-TOC PET offers the highest detection rate in metastatic extra-adrenal PGL and PHEO compared to 18F-DOPA PET and even to diagnostic CT, particularly in bone lesions. Combined functional/anatomical imaging (68Ga-DOTA-TOC PET/CT) enables exact tumour extension to be detected in these rare tumour entities, especially in the case of unclear anatomical correlation.

The impact of adenotonsillectomy on children's quality of life.

OBJECTIVES: Although adenotonsillectomy is one of the most frequently performed surgical procedures in the pediatric population, there is little known about its impact on Health-related Quality of Life (HRQL). The aim of this study was to measure children's HRQL-benefit after adenotonsillectomy. DESIGN AND SETTING: The study was carried out as a retrospective postal survey utilising a proxy rating. PARTICIPANTS: In total, 447 parents of children who underwent adenotonsillectomy for the indication of chronic tonsillitis were included. 43% (n = 191) of the parents returned completed surveys. MAIN OUTCOME MEASURES: To quantify the benefit after pediatric adenotonsillectomy the Glasgow Children's Benefit Inventory (GCBI) was used. RESULTS: Mean GCBI-total score was 21 +/- 19 (-8 to 77), showing an improvement in all GCBI subscales. CONCLUSIONS: Adenotonsillectomy is a highly effective approach to treat children with tonsil disease. It has a positive impact on children's HRQL and other areas not directly associated with their tonsil disease. Moreover, this improvement in HRQL is durable and not temporary.

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.

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.

B cell-mediated infection of stimulated and unstimulated autologous T lymphocytes with HIV-1: role of complement.

In vivo, human immunodeficiency virus type 1 (HIV-1) is opsonized with complement fragments and virus-specific antibodies (Ab). Thus, HIV is able to interact with complement receptor (CR) - and Fc receptor (FcR) - positive cells such as B cells, follicular dendritic cells or macrophages. In this study we demonstrate that the interaction between B cells and HIV has an impact on autologous primary T cell infection in vitro. We confirmed the presence of complement-fragments and virus-specific Ab on serum-treated HIV using a virus-capture assay. In experiments with CR2-specific Ab we showed that the virus/B cell interaction was mainly dependent on CR2. In infection experiments immobilisation of HIV on stimulated tonsil B cells greatly enhanced the infection of interleukin (IL)-2-activated autologous tonsil T cells. Surprisingly, enhancement of T cell infection by B cell-HIV complexes was observed even in the absence of mitogenic stimuli such as PMA and was independent of the addition of exogenous IL-2. Taken together, these results indicate that primary B cells are able to efficiently transmit opsonised HIV to autologous primary T cells and induce a massive enhancement of infection. These in vitro experiments mimic the in vivo situation in the lymphoid tissue and suggest an alternative mechanism for the infection of primary T cells.

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.

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.

Cricoid cartilage necrosis after arytenoidectomy in a previously irradiated larynx.

Several open and endoscopic surgical techniques are available to provide an adequate airway for patients with bilateral vocal cord paralysis. Transoral laser arytenoidectomy has repeatedly been reported to be a reliable and effective minimally invasive procedure for airway restoration. To our knowledge, there have been no previous reports of serious complications, other than poor vocal results, aspiration, and failed decannulation in individual patients, that have resulted from this intervention. We report a case in which arytenoidectomy led to severe complications and death. Prior irradiation is suspected to be a causative factor. To prevent such an outcome, we believe that operative settings should be chosen that avoid deep thermal injury of the laryngeal framework.

Plastination: a new approach to morphological research and instruction with excised larynges.

Impregnation of biologic materials with curable polymer (plastination) allows wider use of human tissue for both basic and clinical research and instruction. The aim of this study was to determine for the first time the potential of this method in the field of laryngology. A feasibility study on 54 pig larynges established a detailed methodology for larynx plastination and determined the extent of shrinkage by using computer-assisted morphometry. The process involves dehydration, saturation with an appropriate intermediate solvent, and infiltration with cured polymer in vacuo. In the main study 20 fresh, intact human larynges and 12 laryngectomy specimens were submitted to plastination. The resulting resin blocks were cut with a diamond band saw into 0.8-mm sections in the transaxial plane. The resulting specimens are dry, odorless, and durable, and do not deteriorate with time. The subtle features of soft tissue pathology are well preserved. Shrinkage of plastinated larynges is less than 10%. The complete process is accomplished within 5 weeks. Staining of sections with toluidine blue provides an enhanced contrast between different types of tissue, allowing a clear identification of tumor invasion. Plastination is considerably faster than celloidin embedding and causes minor anatomic changes. It provides durable specimens of high quality for teaching purposes. In research, it allows the investigation of all tissue components in their undisturbed context in the borderline area between gross anatomy and histology.

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.

Dendritic cells in selected head and neck tumors.

Specimens from 17 head and neck tumor patients were immunohistochemically stained with monoclonal antibodies against HLA-DR, CD1a, RFD1, LAG, CD3, CD4, CD8, CD45RO, CD68, and cytokeratin to identify the nature and distribution of dendritic cells (DCs), T cells, and macrophages. Small numbers of DCs were present in all but 2 specimens. They were located between the tumor cells and in the stroma, especially in areas of inflammatory cell infiltration. Variable numbers of T lymphocytes (cytotoxic and memory type) occurred in the same locations. Numerous macrophages were found in the epithelium, in the stroma, and in the vicinity of tumor cells. The presence of DCs in head and neck tumors indicates that the organism has activated the immune surveillance system and is trying to present tumor antigens. Considering the sparsity of DCs in the malignant tissues, the T cell response can be only limited.

Morphology of the human larynx during the first five years of life studied on whole organ serial sections.

The morphologic development of the human larynx during the first years of life is poorly understood to date. This study used plastinated whole organ serial sections to determine the growth and structure of the infant larynx. The larynges of 43 children 1 to 60 months old were plastinated. Whole organ serial sections were obtained by cutting the resulting specimen with a diamond band saw. The slices were then submitted to computer-assisted morphometric investigation. We found that the subglottic airway rapidly increases in size during the first 2 years of life. Further growth follows a linear mode. The relative proportion of the mucosal lining decreases likewise. In contrast to that in adults, and comparable to that in most mammals, the cartilaginous glottis accounts for 60% to 75% of the vocal folds' length at <2 years. No sexual dimorphism of the larynx exists during childhood. This study supplies detailed morphometric data on the growth and structure of the human larynx during the first years of life. It is the first to use plastinated whole organ serial sections for morphology of the pediatric larynx. Therefore, this study provides quantitative anatomic data of clinical interest that have not been available to date.

Monochromatic x-ray radiation for high resolution radiography in osteology.

The contrast of an x-ray exposure is influenced by the x-ray absorption of the examined material and the x-ray frequency. The examination of the absorbing properties of bone material in the molybdenum spectrum by means of the Bragg-method revealed an intense increase of absorption in the long-wave range. By using a zirconium filter, long-wave and monochromatic MoK alpha-rays can be isolated from the spectrum of a molybdenum x-ray tube. The x-ray exposures of thin bone tissue produced in this spectral range show a much greater degree of contrast and depth as compared to conventional exposures.