[Local recurrence of iodine refractory thyroid cancers. Surgical therapy options for larynx and trachea infiltration]

AIM

 Local recurrence of thyroid carcinomas can result in tumor infiltration in the lower region of the larynx. Since these tumors typically no longer store iodine, treatment options are greatly limited. The present study describes our experience with laryngo-tracheal resection of such cases of local recurrence.

MATERIALS AND METHODS

 From July 2019 to November 2020, we treated five patients with malignant infiltration of the trachea and larynx due to local recurrence of a thyroid carcinoma. We performed laryngo-tracheal resection with end-to-end anastomosis in four patients and frontolateral partial laryngectomy in one patient.

RESULTS

 The median length of hospital stay was 6 days (5-14). An R0 resection was performed in two patients. Problems with the anastomosis or bilateral recurrent laryngeal nerve paralysis was not seen in any of the patients. One patient had to be reintubated on the second postoperative day due to lung failure. He was able to be extubated after five days.

CONCLUSION

 High tracheal resection with partial resection of the larynx was able to be performed with minimal risk. Although radical resections are rare, they expand oncological treatment options in the case of local recurrence of thyroid carcinomas that are iodine-refractory. High tracheal resection could be part of the oncological treatment spectrum in the case of local recurrence of thyroid carcinomas that no longer store iodine.

Common cavity and custom-made electrodes: speech perception and audiological performance of children with common cavity implanted with a custom-made MED-EL electrode

OBJECTIVE

Few studies exist on children with common cavity, fewer still on their long-term audiological development after having received a cochlear implant. Our goal was to observe and report the long-term audiological progress of children with common cavity who were implanted with a custom-made electrode.

METHODS

In this longitudinal, multi-center study, 19 children were implanted with a MED-EL custom-made electrode via either single slit cochleostomy or double posterior labyrinthotomy. We observed their audiological development with a test battery consisting of Categories of Auditory Performance (CAP), Speech Intelligibility Rating (SIR), and Ling 6-Sounds tests. We tested the children 1 month prior to the surgery; at first fitting; at 1, 3, 6, 12, and 18 months post first-fitting; at 2 years after first-fitting; and, whenever possible, at 3, 4, and 5 years after first-fitting.

RESULTS

Children with common cavity tend to steadily and significantly improve their audiological skills over time. This development may, however, be highly individual; probably in part due to relatively high levels of additional needs. Parents should be counseled to establish realistic post-implantation expectations. Surgically, contrary to our expectations, we cannot confirm that double posterior labyrinthotomy reduces intracochlear electrode movement or that the MED-EL custom electrode leads to fewer incidences of intra- or post-implantation complications.

CONCLUSIONS

Cochlear implantation is a safe and effective treatment option in children with common cavity. The majority of children with CC derive significant audiological benefit from implantation. Intra- and post-surgical complications, while serious, and be dealt with effectively in most cases.

Spectrum of novel mutations found in Waardenburg syndrome types 1 and 2: implications for molecular genetic diagnostics

OBJECTIVES

Till date, mutations in the genes PAX3 and MITF have been described in Waardenburg syndrome (WS), which is clinically characterised by congenital hearing loss and pigmentation anomalies. Our study intended to determine the frequency of mutations and deletions in these genes, to assess the clinical phenotype in detail and to identify rational priorities for molecular genetic diagnostics procedures.

DESIGN

Prospective analysis.

PATIENTS

19 Caucasian patients with typical features of WS underwent stepwise investigation of PAX3 and MITF. When point mutations and small insertions/deletions were excluded by direct sequencing, copy number analysis by multiplex ligation-dependent probe amplification was performed to detect larger deletions and duplications. Clinical data and photographs were collected to facilitate genotype-phenotype analyses.

SETTING

All analyses were performed in a large German laboratory specialised in genetic diagnostics.

RESULTS

15 novel and 4 previously published heterozygous mutations in PAX3 and MITF were identified. Of these, six were large deletions or duplications that were only detectable by copy number analysis. All patients with PAX3 mutations had typical phenotype of WS with dystopia canthorum (WS1), whereas patients with MITF gene mutations presented without dystopia canthorum (WS2). In addition, one patient with bilateral hearing loss and blue eyes with iris stroma dysplasia had a de novo missense mutation (p.Arg217Ile) in MITF. MITF 3-bp deletions at amino acid position 217 have previously been described in patients with Tietz syndrome (TS), a clinical entity with hearing loss and generalised hypopigmentation.

CONCLUSIONS

On the basis of these findings, we conclude that sequencing and copy number analysis of both PAX3 and MITF have to be recommended in the routine molecular diagnostic setting for patients, WS1 and WS2. Furthermore, our genotype-phenotype analyses indicate that WS2 and TS correspond to a clinical spectrum that is influenced by MITF mutation type and position.

Assessment of tinnitus-related impairments and disabilities using the German THI-12: sensitivity and stability of the scale over time

OBJECTIVE

To evaluate the reliability, dimensionality, predictive validity, construct validity, and sensitivity to change of the THI-12 total and sub-scales as diagnostic aids to describe and quantify tinnitus-evoked reactions and evaluate treatment efficacy.

DESIGN

Explorative analysis of the German tinnitus handicap inventory (THI-12) to assess potential sensitivity to tinnitus therapy in placebo-controlled randomized studies. Correlation analysis, including Cronbach's coefficient α and explorative common factor analysis (EFA), was conducted within and between assessments to demonstrate the construct validity, dimensionality, and factorial structure of the THI-12.

STUDY SAMPLE

N = 618 patients suffering from subjective tinnitus who were to be screened to participate in a randomized, placebo-controlled, 16-week, longitudinal study.

RESULTS

The THI-12 can reliably diagnose tinnitus-related impairments and disabilities and assess changes over time. The test-retest coefficient for neighboured visits was r > 0.69, the internal consistency of the THI-12 total score was α ≤ 0.79 and α ≤ 0.89 at subsequent visits. Predictability of THI-12 total score and overall variance increased with successive measurements. The three-factorial structure allowed for evaluation of factors that affect aspects of patients' health-related quality of life.

CONCLUSIONS

The THI-12, with its three-factorial structure, is a simple, reliable, and valid instrument for the diagnosis and assessment of tinnitus and associated impairment over time.

A randomized, double-blind, placebo-controlled clinical trial to evaluate the efficacy and safety of neramexane in patients with moderate to severe subjective tinnitus

Background

Neramexane is a new substance that exhibits antagonistic properties at α₉α₁₀ cholinergic nicotinic receptors and N-methyl-D-aspartate receptors, suggesting potential efficacy in the treatment of tinnitus.

Methods

A total of 431 outpatients with moderate to severe subjective tinnitus (onset 3-18 months before screening) were assigned randomly to receive either placebo or neramexane mesylate (25 mg/day, 50 mg/day and 75 mg/day) for 16 weeks, with assessment at 4-week intervals. The primary (intention-to-treat) efficacy analysis was based on the change from baseline in Week 16 in the total score of the adapted German short version of the validated Tinnitus Handicap Inventory questionnaire (THI-12).

Results

Compared with placebo, the largest improvement was achieved in the 50 mg/d neramexane group, followed by the 75 mg/d neramexane group. This treatment difference did not reach statistical significance at the pre-defined endpoint in Week 16 (p = 0.098 for 50 mg/d; p = 0.289 for 75 mg/d neramexane), but consistent numerical superiority of both neramexane groups compared with placebo was observed. Four weeks after the end of treatment, THI-12 scores in the 50 mg/d group were significantly better than those of the controls. Secondary efficacy variables supported this trend, with p values of < 0.05 for the 50 mg/d neramexane group associated with the functional-communicational subscores of the THI-12 and the assessments of tinnitus annoyance and tinnitus impact on life as measured on an 11-point Likert-like scale. No relevant changes were observed for puretone threshold, for tinnitus pitch and loudness match, or for minimum masking levels. The 25 mg/d neramexane group did not differ from placebo. Neramexane was generally well tolerated and had no relevant influence on laboratory values, electrocardiography and vital signs. Dizziness was the most common adverse event and showed a clear dose-dependence.

Conclusions

This study demonstrated the safety and tolerability of neramexane treatment in patients with moderate to severe tinnitus. The primary efficacy variable showed a trend towards improvement of tinnitus suffering in the medium- and high-dose neramexane groups. This finding is in line with consistent beneficial effects observed in secondary assessment variables. These results allow appropriate dose selection for further studies.

Trial Registration

ClinicalTrials.gov NCT00405886

Simvastatin and Ginkgo biloba in the treatment of subacute tinnitus: a retrospective study of 94 patients

OBJECTIVES

Studies suggest that hypercholesterolemia promotes the development of inner ear disorders such as tinnitus. However, the underlying pathomechanisms are still not clearly defined.

METHODS

A retrospective study was performed to assess whether a reduction of serum cholesterol by 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors may result in a relief of subacute tinnitus. Remission rates of 58 patients were investigated after 4 months of treatment with simvastatin (40 mg). Results were compared to treatment with Ginkgo biloba (120 mg; n = 36) as control group. Differences between tinnitus score at the day of first treatment and after 4 months were used as main outcome measure.

RESULTS

After treatment with simvastatin or G biloba, tinnitus score decreased from 41.3 ± 10.4 to 37.4 ± 17.3 and from 44.7 ± 11.2 to 41.2 ± 8.7, respectively. However, independently of the treatment regimen, differences of tinnitus scores were considered not significant.

CONCLUSIONS

After administration of simvastatin over 4 months, this retrospective study has shown no significant efficacy in treatment of subacute tinnitus. For a more conclusive answer, further prospective, double-blind, and placebo-controlled studies with a larger number of patients are needed.

Perspectives on the pathophysiology and treatment of sudden idiopathic sensorineural hearing loss

BACKGROUND

Sudden, idiopathic sensorineural hearing loss is an acute dysfunction of the inner ear whose cause cannot be determined with the currently available methods of clinical diagnosis.

METHODS

This continuous medical education article is based on a selective review of the literature and on the revised S2 guidelines for acute sensorineural hearing loss of the Association of the Scientific Medical Societies in Germany (AWMF), which were issued on 28 January 2009.

RESULTS

Recent surveys in Germany suggest that the incidence of sudden, idiopathic sensorineural hearing loss may be as high as 300 per 100,000 persons per year. To distinguish this entity from acute hearing loss of other causes, special tests are necessary, including ear microscopy, pure-tone audiometry, and acoustic evoked response audiometry. No clinical trial of the highest evidence level has yet been published to document the efficacy of any type of treatment for sudden, idiopathic sensorineural hearing loss. Nonetheless, there is evidence from trials with lower levels of evidence, post-hoc analyses, and assessments of secondary endpoints of clinical trials indicating that plasma-expander therapy, the systemic and local (intratympanic) administration of cortisone, and the reduction of acutely elevated plasma fibrinogen levels may be beneficial.

CONCLUSION

Further clinical trials are needed to validate these preliminary results. Until clear data are available, the predicted benefit and risk of any proposed treatment for sudden, idiopathic sensorineural hearing loss should be discussed in detail with the patient before the treatment is begun.

WITHDRAWN: [Effects of atorvastatin on presbyacusis and tinnitus : A prospective, randomized, double-blind clinical trial.]

Ahead of Print article withdrawn by publisher

Effect of atorvastatin on progression of sensorineural hearing loss and tinnitus in the elderly: results of a prospective, randomized, double-blind clinical trial

OBJECTIVE

To test whether the 3-hydroxy-3-methylglutaryl- coenzyme A reductase inhibitor atorvastatin can slow down the progression of presbycusis.

PATIENTS

Fifty patients 60- to 75-years-old with presbycusis and moderately elevated serum cholesterol.

INTERVENTION(S)

In a double-blind design, patients were randomly assigned to treatment with either atorvastatin (40 mg/d orally) or placebo.

MAIN OUTCOME MEASURE(S)

Pure-tone audiometry and tinnitus evaluation at enrolment and after 7 and 13 months.

RESULTS

Development of hearing thresholds after 7 and 13 months showed no significant differences between the groups. Tinnitus score continuously improved in the atorvastatin group (34.8 at 7 and 27.6 at 13 mo), whereas it slightly deteriorated in the placebo group (24.8 at 7 and 26.8 at 13 mo). The effect on tinnitus was a tendency without statistic significance (p = 0.0833).

CONCLUSION

Atorvastatin had no effect on the development of hearing thresholds, but resulted in a trend toward a relief of tinnitus.

[Up to date: therapy of sudden hearing loss]

Sudden sensorineural hearing loss is thought to be of different origin. Disturbances of microcirculation, autoimmune pathology and viral infection are among the most likely causes. The shape of the puretone audiogram can be a useful clue to its origin. Following is a description of five different forms of sudden hearing loss, its suspected pathogenesis and different therapeutic strategies recommended for the treatment of sudden hearing loss.

[The incidence of sudden hearing loss is greater than previously assumed]

The global incidence of sudden hearing loss is quoted to be 5-20 new cases/100,000 inhabitants/year. In the opinion of the present authors, the data on which these figures are based, are too old, methodologically questionable and non-transferable. An analysis of data from the compulsory health insurance carriers in Baden-Württemberg and the Nordrhein district suggests that an appreciably higher incidence must be assumed for Germany. Statistical processing of the numerical data of all cost carriers is necessary if we are to obtain an accurate incidence for Germany.

[Synovial sarcoma of the hypopharynx - two case reports]

BACKGROUND

Synovial sarcoma is a rare soft tissue malignancy that most often occurs in the extremities of young adults. Approximately 3 % of these mesenchymal malignant tumors occur in the head and neck region. Up to now about 100 cases have been published.

PATIENTS

We report on two cases of a synovial sarcoma of the hypopharynx. In the first case the patient died 3.5 years after beginning of therapy including all therapeutical efforts (surgery, chemotherapy, radiotherapy). The second patient with a synovial sarcoma of his left hypopharynx and a distant metastasis in his 8th thoracic vertebral body is actually treated by neoadjuvant chemotherapy and included into a clinical study to optimize therapy of advanced soft tissue sarcomas. Further surgical treatment depends on the success of this therapeutic approach.

CONCLUSION

Despite multitherapeutic approaches over all 5-year survival rates for advanced synovial sarcomas of the head and neck have moderately improved in the recent decades and an ideal treatment has not yet surfaced. Modification of accepted treatment modalities is discussed and therapy options in controlled clinical studies are described.

[Acute diseases of the inner ear--are cardiovascular treatment strategies lacking?]

The underlying cause of acute functional disorders of the inner ear (sudden hearing loss) is usually not detectable with clinical diagnostic measures. It is assumed that functional disorders of the inner ear are merely symptoms and not a disease entity in itself. In particular regional perfusion disturbances, but also autoimmune phenomena, viral infections and micromechanical disorders of the cochlea are seen as pathogenetic principles in inner ear disturbances. Although numerous effective therapeutic options and prophylactic measures for such diseases as myocardial infarction and stroke are available to cardiovascular medicine, they have so far not been applied to the treatment of inner ear problems. Here there is a promising and wide field of options for such diseases that can be traced back to regional perfusion disorders.

Round Window Application of D-Methionine, Sodium Thiosulfate, Brain-Derived Neurotrophic Factor, and Fibroblast Growth Factor-2 in Cisplatin-Induced Ototoxicity

HYPOTHESIS

In this study we tested the effect of local administration of D-methionine, sodium thiosulfate, brain-derived neurotrophic factor, and fibroblast growth factor-2 on cisplatin ototoxicity in guinea pigs to the round window membrane.

BACKGROUND

Cisplatin is an important antineoplastic agent in the therapy of many malignancies. Its clinical utility is limited by severe side effects, including ototoxicity. Recent studies have shown protection against cisplatin ototoxicity in animal experiments by the systemic administration of D-methionine and sodium thiosulfate. Growth factors such as brain-derived neurotrophic factor and fibroblast growth factor-2 also have shown otoprotective effects in in vitro studies.

METHODS

Osmotic pumps (Alzet) were implanted unilaterally in 30 guinea pigs. Five groups of six animals received either D-methionine, sodium thiosulfate, fibroblast growth factor-2, brain-derived neurotrophic factor, or saline 0.9%. Cisplatin was administered intraperitoneally for 5 consecutive days. Distortion product otoacoustic emissions were recorded every day. The animals were killed on day 6, and their cochleae were removed and analyzed by transmission electron microscopy.

RESULTS

Compared with control animals, guinea pigs treated with D-methionine showed better otoacoustic emissions on days 3 and 4 (Mann-Whitney test, p < 0.05). The differences were not evident on days 5 and 6. Sodium thiosulfate, brain-derived neurotrophic factor, and fibroblast growth factor-2 showed no significant protective effect.

CONCLUSION

Local application to the round window membrane can be used as an effective treatment in the prevention of cisplatin toxicity. Local application may avoid systemic side effects and reduce the antineoplastic effects of cisplatin.

Behandlung des H�rsturzes durch Fibrinogen-LDL-Apherese

INTRODUCTION

Sudden sensorineural hearing loss (SSHL) is thought to be of various origins. Disturbances of microcirculation, autoimmune pathology and viral infection are among the most likely causes. Acute reduction of plasma fibrinogen and serum LDL positively influences hemorheology and endothelial function and might thus be an effective therapy for SSHL.

OBJECTIVE

To test the hypothesis that fibrinogen/LDL-apheresis is as effective or superior to conventional therapy with plasma expanders and prednisolone in the treatment of SSHL.

DESIGN

controlled, prospective, randomized, multicenter trial.

SETTING AND PATIENTS

201 patients were recruited from 01/2000 to 6/2001 at the University Clinics of Munich, Berlin, Hamburg and Bochum. Inclusion criteria was sudden sensorineural hearing loss of unknown origin within 6 days of onset.

INTERVENTIONS

Single fibrinogen/ LDL-apheresis infusion of prednisolone (250 mg, tapered by 25 mg daily), hydroxyethyl starch (500 ml, 6%) and pentoxifylin (400 mg/day).

MAIN OUTCOMES

Improvement of pure tone thresholds 48 h after onset of therapy.

RESULTS

Over all improvement of pure tone thresholds in the fibrinogen/ LDL-apheresis treated patients is slightly but not significantly better than in the standard therapy group. After 48 h, 50% speech perception in the fibrinogen/ LDL-apheresis group (21.6+/-20.1 dB) is significantly (p<0.034) better than in the standard group (29.3+/-29.4 dB). Patients with plasma fibrinogen levels of more than 295 mg/dl have a substantial and significantly (p<0.005) better improvement of speech perception (15.3+/-17.3 dB) than standard treated patients (6.1+/-10.4 dB).

CONCLUSIONS

Fibrinogen/LDLapheresis is at least equally effective compared to prednisolone treatment in sudden hearing loss. Selected patients with plasma fibrinogen of more than 295 mg/dl improve significantly better when treated with fibrinogen/LDLapheresis.

Prognostic implications of hemoglobin levels before and after surgery as well as before and after radiochemotherapy for head and neck tumors

Several studies have shown that tumor cells may develop resistance to radiotherapy, proliferating under hypoxic conditions. Following surgery, patients may develop low hemoglobin levels, which may cause low oxygen conditions. This retrospective analysis was undertaken to determine the impact of low hemoglobin levels in patients with head and neck tumors treated with combined-modality therapy (surgery and postoperative radiochemotherapy). We studied 120 patients with mostly advanced head and neck tumors (88% stage III/IV) who had undergone macroscopically complete resections of their primary tumors and lymph node metastases. At 20-277 days after surgery (median: 51.3 days), these patients received postoperative chemoradiotherapy (56.7 Gy of radiation over 28-49 days and cisplatin 6 mg/m(2) body surface area on radiation treatment days with a cumulative dose of 96 mg/m(2)). Normal hemoglobin levels were considered to be 12 g/dl for females and 13 g/dl for males. Decreased hemoglobin levels before or after surgery and before or after chemoradiotherapy were correlated with the prognosis. Preoperatively, 99 of 114 patients (87%) had normal levels of hemoglobin compared with only 20 of 107 patients (19%) postoperatively. At the onset of radiochemotherapy, the hemoglobin levels of 82 of 116 patients (71%) were within the normal range. After radiochemotherapy, however, 62 of 114 patients (54%) had normal hemoglobin levels. Univariate analysis (Kaplan-Meier method and log-rank test) showed that patients with decreased pre- or postoperative hemoglobin levels had significantly worse locoregional control ( P=0.032 and P=0.0001, respectively) and lower overall survival ( P=0.0013 and P=0.0002, respectively) than patients with normal hemoglobin levels. The 3-year locoregional control rates in patients with preoperative hemoglobin levels that were normal, were reduced by 1-2 g/dl or were reduced by more than 3 g/dl, respectively, were 78%, 55% and 50%. Correlated with normal and diminished postoperative hemoglobin levels, the 3-year locoregional control rates were 90%, 84% and 50%, respectively. There was no correlation between prognosis and hemoglobin level at the onset or after radiochemotherapy. On multivariate analysis, only the postoperative hemoglobin level remained a prognostic factor for locoregional control ( P=0.0241) and overall survival ( P=0.0080). We conclude that low postoperative hemoglobin levels resulting from blood loss may influence the efficacy of postoperative radiochemotherapy in patients with head and neck cancer. Early intervention to raise the postoperative hemoglobin level may result in better tumor control and overall survival after combined-modality therapy.

[Audimont--a scientific research expedition to Mount Cho Oyu in the Himalayas]

Even though hearing and vestibular disorders at high altitude have been reported since 1938, their reasons are still unknown. During the Audimont Research Expedition the risk for cochlear and vestibular sensory cells has been quantified by otoacoustic emissions and videonystagmography. Vestibular disorders could not be observed up to 7050 meters. However, the outer hair cells in the inner ear showed a reduction of emissions at increasing height. The pattern of the inner ear reply, depending on the altitude, complies with an increase of the perilymphatic pressure. As the perilymphatic space corresponds directly to the subarachnoid space, the limitation of hearing thus appears to be a direct consequence of raised intracranial pressure.

Fibrinogen and LDL apheresis in treatment of sudden hearing loss: a randomised multicentre trial

BACKGROUND

Sudden sensorineural hearing loss (SSHL) is thought to have many different origins, including disturbances of microcirculation, autoimmune pathology, and viral infection. We aimed to determine whether acute reduction of plasma fibrinogen and serum LDL is effective for treatment of SSHL of suspected vascular origin.

METHODS

Between January, 2000, and June, 2001, we recruited 201 patients with sudden hearing loss from four otorhinolaryngology clinics in Germany. Patients were randomly allocated to single fibrinogen/LDL apheresis or standard treatment (250 mg prednisolone reduced by 25 mg per day, 500 mL 6% hydroxyethyl starch, 400 mg pentoxifylline per day). The primary outcome was recovery of hearing as measured by pure-tone audiometry 48 h after the start of treatment. Secondary outcomes were recovery of hearing 6 weeks after treatment, improvement of speech audiometry, tinnitus, and frequency of side-effects. Analysis was done per protocol.

FINDINGS

Overall improvement of pure-tone thresholds was slightly but not significantly better in patients given apheresis than in those given standard treatment (difference 7.7, 95% CI -8.2 to 23.6). However, the mean sound level at which 50% of recorded digits were recognised was significantly lower after 48 h in the apheresis group (21.6 dB, SD 20.8) than in the standard group (29.3 dB, 29.4; p=0.034). After 6 weeks, the mean 50% speech perception was at 13.6 dB (SD 14.3) in the apheresis group and at 20.8 dB (25.4) in those on standard treatment (p=0.059). At 48 h, in patients with plasma fibrinogen concentrations of more than 295 mg/dL, speech perception was improved much more in those on apheresis (15.3 dB, 17.3) than in those on standard treatment (6.1 dB, 10.4; p=0.005).

INTERPRETATION

A single fibrinogen/LDL apheresis lasting for 2 h could be used as an alternative to conventional infusion treatment and prednisolone for 10 days. Patients with a plasma fibrinogen of more than 8.68 micromol/L improve much better when treated with apheresis, especially if serum LDL concentrations are also raised.

[Cochlear and vestibular risk at high altitude]

Exposure to lowered oxygen pressure at high altitude results in various physiological reactions. The most important response besides hyperventilation is the elevation of the oxygen transport capacity, which simply is achieved by plasma diuresis. Hemoconcentration however not only increases oxygen uptake but also raises blood viscosity, serum osmolality and impairs blood flow. Various observations have suggested that hearing and postural properties deteriorate under these conditions at high altitude. Studies in hypobaric chambers and our own data indicate that the elevated hematocrit levels and hypoxemia may impair the central nervous system functions, resulting in altered speech discrimination, directional hearing, and postural control. However, there is no evidence that cochlear and vestibular sensory cells are affected, whether by acute hypoxia, nor by elevated hematocrit levels up to 58 %. Even an greater increase in serum osmolality or an impaired osmoregulation may not interfere with the outer hair cell function resulting in threshold shift and hearing loss.

Hyperfibrinogenemia as a risk factor for sudden hearing loss

OBJECTIVE

To clarify predisposing conditions for vascular events.

SETTING

Vascular events, immunologic processes, and viral infections have to be considered as pathomechanisms for most cases of sudden hearing loss.

STUDY DESIGN

Hemorrheologic parameters were studied in 53 patients with sudden hearing loss within 5 days of the onset.

PATIENTS

A control group of 53 normal-hearing people was matched pairwise according to age and gender.

RESULTS

Fibrinogen levels were significantly higher in patients with sudden hearing loss (343 +/- 98 mg/dl) than in control subjects (303 +/- 69 mg/dl). Erythrocyte aggregation (27.3 +/- 5.6 a.u. versus 20.9 +/- 8.5 a.u.) and plasma viscosity (1.31 +/- 0.13 mPa/s versus 1.26 +/- 0.08 mPa/s) in patients with SHL were also significantly higher than in control subjects. No significant difference could be found in the parameters of clinical chemistry, hematology, and hemostasias investigated.

CONCLUSION

Because elevated plasma fibrinogen plays a major role in cardiovascular diseases such as myocardial infarction and stroke, it is possible that this plasma protein is also involved in the pathogenesis of sudden hearing loss of vascular origin. More research is still required to determine the value of measuring plasma fibrinogen levels in clinical practice and identifying hyperfibrinogenemia in sudden hearing loss.

[A patient with acoustic neuroma--The reason for the functional disorder of his inner ear?]

BACKGROUND

Acoustic neuroma is one of the classic causes of retrocochlear hearing disorders. Auditory brainstem response (ABR) testing with a sensitivity of about 90 % in the diagnosis of acoustic neuroma plays an important role as a screening method.

CASE REPORT

A patient suffering from an acute, unilateral sensorineural hearing loss with tinnitus recovered for a short period of time after being treated with low density lipoprotein (LDL-) apheresis improving hemorheology. Surprisingly, the reason for the sudden hearing loss was a tumor in the cerebellopontine angle with a maximum diameter of 2 cm, which was detected by magnetic resonance imaging (MRI). Auditory brainstem response testing (ABR), audiovestibular tests and other standard tests were negative concerning this diagnosis. There was no previous evidence for an acoustic neuroma in all investigations of cochlear disfunction except MRI.

CONCLUSIONS

The acoustic neuroma caused a compression of the labyrinthine artery in the inner auditory canal resulting in an acute unilateral hearing loss with tinnitus. Low Density Lipoprotein-apheresis was able to achieve a short term improvement of blood supply to the inner ear. Thus the compression of the labyrinthine artery caused by an acoustic neuroma could be compensated for the duration of about one week. Within this time the effect of LDL-apheresis decreased more and more. After a sudden unilateral hearing loss an acoustic neuroma must be ruled out even if the retrocochlear testing by ABR primarily shows no prolonged interpeak latency.

Heparin-Induced extracorporeal low-density lipoprotein precipitation apheresis: a new therapeutic concept in the treatment of sudden hearing loss

Vascular events, immunological processes, and viral infections have to be considered as pathomechanisms for most cases of sudden hearing loss (SHL). In order to clarify predisposing conditions for vascular events. hemorheological parameters have been studied in 53 patients suffering from SHL within 5 days of onset, along with a control group. The striking result was a significantly elevated level of plasma fibrinogen leading to a significantly increased erythrocyte aggregation and plasma viscosity. No significant difference could be found in all other parameters of clinical chemistry, hematology, and hemostasis. These results encouraged us to use heparin-induced extracorporeal low-density lipoprotein (LDL) precipitation (HELP) apheresis, which acutely and drastically reduces LDL. fibrinogen, and lipoprotein (a) in the treatment of patients suffering from sudden hearing loss and hyperfibrinogenemia or hypercholesterolemia. In a pilot study including 30 patients, we found a better recovery of hearing in the patients treated with a single HELP apheresis when compared to conventional treatment for 10 days with prednisolone and dextranes. Currently, we verify these results in a larger multicenter trial in patients regardless of their fibrinogen or LDL levels. In the future, there will be different specific treatments of sudden hearing loss based on the different pathomechanisms. The clinical impression and first controlled data make it likely that HELP apheresis is useful in the therapy of sudden hearing loss with suspected vascular origin.

Heparin-induced extracorporal low-density-lipoprotein precipitation (H.E.L.P.) to improve the recovery of hearing in patients with sudden idiopathic hearing loss

The pathogenesis of sudden hearing loss (SHL) is still not well understood. Possible causes include increased blood viscosity, microthrombosis or altered blood flow. Hypercholesterolemia, hyperfibrinogenemia and increased platelet aggregation are frequently observed in patients with SHL. The aim of this study was to investigate whether drastic lowering of plasma cholesterol and fibrinogen by selective extracorporal apheresis could have a beneficial effect on hearing recovery in these patients. Seven patients with SHL were treated with an extracorporal procedure removing fibrinogen and cholesterol from plasma. Six of the seven patients showed an immediate improvement in auditory thresholds following a single treatment of heparin-induced low-density lipoprotein precipitation. These findings indicate for the first time that acute and drastic removal of plasma fibrinogen and low-density lipoproteins may be an effective clinical method for the treatment of patients with SHL.

Clinical utility of LDL-apheresis in the treatment of sudden hearing loss: a prospective, randomized study

Although the pathogenesis of sudden hearing loss (SHL) is not as yet known, the clinical picture and the frequent association with vascular risk factors make an ischaemic event likely. This study aimed to assess the effect of an extracorporeal procedure (H.E.L.P.) in removing LDL-cholesterol, fibrinogen and lipoprotein (a) from the plasma, on the recovery of hearing SHL. This procedure using the HELP-system was compared with the usual standard treatment with prednisolone, dextranes and pentoxifyllin. We undertook a single centre, prospective, randomized study in which 18 patients were assigned to H.E.L.P.-apheresis and 9 patients were assigned to standard treatment (2:1 randomization). Audiometric and laboratory testing was performed at baseline, 24 h and 6 weeks after start of treatment. Primary endpoint was the improvement of the average pure-tone threshold between 0.125 and 8 kHz after 24 h. Twenty-four hours after H.E.L.P. treatment average pure-tone threshold recovered by 10.4 dB and by 26.4 dB after 6 weeks. The recovery of hearing of the standard treated patients was 5.8 dB and 16.8 dB after 24 h and 6 weeks respectively. LDL-cholesterol, fibrinogen and lipoprotein (a) were significantly reduced in the HELP treated patients compared with standard therapy, resulting in a significant improve in plasma viscosity, erythrocyte aggregation and resistance to oxidative stress of LDL particles. Our results suggest that the clinical outcome of SHL after a single extracorporeal LDL-apheresis is superior or at least equal to the more expensive standard treatment with prednisolone, dextranes and pentoxifyllin. Re-establishment of vascular endothelial function and improved blood rheology may be the underlying cause. These results must be confirmed in larger-scale trials.

Evaluation of the middle and inner ear structures: comparison of hybrid rendering, virtual endoscopy and axial 2D source images

Recent developments in 3D reconstructions can enhance the quality and diagnostic value of axial 2D image data sets with direct benefits for clinical practice. To show the possible advantages of a hybrid rendering method [color-coded 3D shaded-surface display (SSD)- and volume rendering method] with the possibility of virtual endoscopy we have specifically highlighted the use in relation to the middle and inner ear structures. We examined 12 patients with both normal findings and postoperative changes, using image data sets from high-resolution spiral computed tomography (HRSCT). The middle and inner ear was segmented using an interactive threshold interval density volume-growing method and visualized with a color-coded SSD rendering method. The temporal bone was visualized using a transparent volume rendering method. The 3D- and virtual reconstructions were compared with the axial 2D source images. The evaluated middle and inner ear structures could be seen in their complete form and correct topographical relationship, and the 3D- and virtual reconstructions indicated an improved representation and spatial orientation of these structures. A hybrid and virtual endoscopic method could add information and improve the value of imaging in the diagnosis and management of patients with middle or inner ear diseases making the understanding and interpretation of axial 2D CT image data sets easier. The introduction of an improved rendering algorithm aids radiological diagnostics, medical education, surgical planning, surgical training, and postoperative assessment.

[All sudden hearing losses are not alike. Away from infusion therapy?]

The number of patients requiring treatment for acute functional disorders of the inner ear has increased over the last decades. The diagnosis sudden loss of hearing is made when the cause of a precipitous hearing impairment cannot be determined with clinical diagnostic means. In the large majority of such cases, the pathogenesis is unclear, with vascular, viral and autoimmune processes most commonly being considered. Against this background, numerous polypragmatic therapeutic measures are employed. In general treatment of sudden loss of hearing employs a combination of several drugs with perfusion-promoting or anti-inflammatory effects. However, the efficacy of such an approach has not been established. The present article discusses a number of known ideas on the pathogenesis of this condition, together with the associated therapeutic strategies, and reports on the importance of nitrogen oxide (NO), which as recent studies appear to show, plays an important role in the physiology of the cochlea.

[Pseudoaneurysm of the lingual artery after tonsillectomy. A rare complication]

BACKGROUND

Tonsillectomy is one of the most common surgical procedures in otorhinolaryngology; however, life-threatening complications can occur in rare cases.

PATIENTS

We report about a seven-year-old girl who developed a pseudoaneurysm of the lingual artery following elective routine tonsillectomy.

RESULTS AND CONCLUSION

Initial ENT examination will reveal a painful cervical mass or unilateral palatal swelling that can easily be misinterpreted as a peritonsillar (or parapharyngeal) abscess. Computed tomography and angiography are indicated to confirm the diagnosis. Bleeding from a pseudoaneurysm of any branch of the external carotid artery represents a serious and life-threatening complication. Surgery is the treatment of choice.

Changes in serum osmolarity influence the function of outer hair cells

Fast motility of outer hair cells (OHC) is thought to be based on a hydromechanic principle. In vitro, the function of OHCs can be disturbed by a change in the osmolarity of the culture medium. Whether changes in the serum osmolarity in vivo can also interfere with OHC motility has not been investigated as yet. Serum osmolarity of New Zealand White rabbits (n = 18) was elevated by a continuous infusion of glucose 40%, decreased by an infusion of aqua dest, or kept constant by an infusion of saline. OHC function was monitored using distortion products of otoacoustic emissions (DPOAE). Input output curves were established between 2 and 5 kHz (geometric mean of f2) with primaries of levels between 35 and 55 dB SPL. Cochlear perfusion was measured using a fluorescence microsphere method. Elevation of the serum osmolarity from 306 +/- 17 mosm/l to 365 +/- 23 induced a decrease of DPOAE between 3 and 12 dB SPL. Cochlear blood flow increased from 0.11 +/- 0.09 to 0.15 +/- 0.10 ml/min/g. When decreasing the serum osmolarity from 303 +/- 9 to 281 +/- 8 mosm/l, only slight changes of the DPOAE could be verified. As in the control group, cochlear perfusion was almost unchanged. In the control group, neither serum osmolarity nor DPOAE changed. Comparable to findings in vitro, increasing the serum osmolarity can lead to a disturbance of OHC function. In patients suffering from sudden hearing loss. dehydration due to physical or mental stress is often observed. This new and promising pathophysiological concept needs further clinical evaluation.

[Exploratory analysis of risk factors of acute inner ear dysfunctions]

Aside from the clinical picture, the frequent occurrence of vascular risk factors favors a vascular pathogenesis of acute sensorineural hearing loss. However, the data on the association of vascular risk factors with sensorineural hearing loss are controversial. Achieving a sufficient number of patients and establishing a suitable control group is difficult. We analyzed the data of 393 patients suffering from acute sensorineural hearing loss. Risk factors, general, audiological, and laboratory parameters were investigated. Mean hearing loss and remission during 10 days of hospital treatment were calculated. The patient group was divided into patients with a certain risk factor and those without this risk factor, and mean remission and hearing loss were compared. Patients suffering from hyperlipidemia or hypotension had substantial and significantly higher mean hearing losses than patients not suffering from these diseases. Thrombosis, embolism, and hypertension were associated with a significantly worse remission of hearing loss. Repeated episodes of sensorineural hearing loss showed a significant worse remission, but less mean hearing loss before therapy. Smoking, diabetes mellitus, infections of the upper airways, and allergies had no influence on remission and mean hearing loss.

Hemoconcentration as a possible pathogenic factor of sudden hearing loss

Hemodilution is considered to be a useful therapy for sudden hearing loss by improving cochlear blood flow (COBF) as a result of decreasing viscosity of the whole blood. The purpose of this investigation was to evaluate whether hemoconcentration actually leads to a diminished COBF and impaired function of the cochlea to thus play a role in the pathogenesis of sudden hearing loss. Ten New Zealand White rabbits were anesthetized and ventilated. Cochlear function was evaluated by measuring distortion products of otoacoustic emissions (DPOAEs) at the beginning of each experiment and after 120 min. In the interim, each test animal's hematocrit was raised by an infusion of packed red cells. Control animals were not infused, so hematocrits were left unchanged. Reproducibility of DPOAE measurements were found to be dependent upon the stimulus level. Correlation coefficients were 0.83 for 65 dB SPL and 0.78 for 45 dB SPL. Although no changes in the absolute level of DPOAEs were observed after raising the hematocrit, correlation coefficients were diminished to 0.68 at 65 dB SPL and 0.58 at 45 dB SPL. Hemoconcentration caused no apparent changes in the cochlear function in our animals. Although these findings may reflect species differences, hemoconcentration might still be a factor causing sudden hearing loss in older, atherosclerotic patients.

[Hypercholesteremia and hyperfibrinogenemia in sudden deafness]

BACKGROUND

The pathogenesis of sudden hearing loss has not been elucidated as yet. Insufficient perfusion of the cochlea due to an increased blood viscosity, microthrombosis, or altered vasomotion are assumed. Hypercholesterolemia and hyperfibrinogenemia are frequently observed in patients with sudden sensorineural hearing loss. The aim of this study was to investigate the incidence of hypercholesterolemia and hyperfibrinogenemia in patients suffering from sudden hearing loss compared to normal controls. In an intervention study the impact of drastic lowering of plasma cholesterol and fibrinogen by a selective extracorporal apheresis was studied.

METHODS

In a case-control study of 23 patients suffering from sudden hearing loss, plasma cholesterol and fibrinogen levels as well as erythrocyte aggregation and plasma viscosity were determined. Seven sudden hearing loss patients from this group were treated with H.E.L.P. apheresis, an extracorporal procedure removing fibrinogen and idl-cholesterol from plasma.

RESULTS

Plasma fibrinogen and cholesterol levels were higher in sudden hearing loss patients, leading to significantly elevated values of erythrocyte aggregation and plasmaviscosity. Six out of the seven patients treated with a single H.E.L.P. apheresis immediately showed an improvement of auditory thresholds.

CONCLUSIONS

We conclude that hyperfibrinogenemia and hypercholesterolemia may contribute to the clinical event of sudden hearing loss. Our study shows for the first time that acute and drastic removal of plasma fibrinogen and low density lipoproteins can be an effective clinical tool in the treatment of patients with sudden hearing loss.

[Possibility for quantitative and frequency-specific assessment of auditory threshold with otoacoustic emissions]

BACKGROUND

Otoacoustic emissions can be used to study cochlear function in a non-invasive manner. They are an effective clinical tool for infant hearing screening. The purpose of this study was to determine their utility for a frequency-specific and quantitative estimation of the hearing threshold.

METHODS

Transiently evoked otoacoustic emissions (TEOAE) and distortion-product emissions (DPOAE) were recorded from 16 normal and 86 hearing impaired ears and correlated with their hearing threshold between 0.5 and 6.0 kHz.

RESULTS

The correlations of TEOAE and the hearing threshold ranged from 0.53 (0.5 kHz) to 0.69 (6.0 kHz), of the DPOAE from 0.51 (0.5 kHz) to 0.83 (6.0 kHz). Based on the optimal correlating OAE frequency we tried to predict the hearing threshold. We obtained 95% prediction intervals for TEOA between 19 dB (1.0 kHz) and 39 dB (4.0 and 6.0 kHz), for DPOAE between 21 dB (1.0) and 34 dB (3.0 and 4.0 kHz).

CONCLUSION

Despite their clinically irrelevant greater prediction intervals at the low frequencies, our results suggest that DPOAEs are generally more valuable for the frequency-specific estimation of the hearing threshold. Prediction intervals may improve the interpretation of OAEs.

Tissue oxygen measurement and 31P magnetic resonance spectroscopy in patients with muscle tension and fibromyalgia

Muscle tissue oxygen tension was measured by a polarographic oxygen fine-needle probe, and inorganic phosphate and creatine phosphate spectra were recorded using magnetic resonance spectroscopy in patients with chronic low back pain and in patients with fibromyalgia. Results were compared with healthy controls. The tissue oxygen tension was markedly higher in those with tense muscles than in normal subjects. Magnetic resonance spectra for inorganic phosphate were higher in patients demonstrating muscle contraction, and intracellular pH was shifted in the alkaline direction in cases with increased muscle tension. Results show that hypoxia is not the result of increased muscle tension, as was thought previously, but results from oversupply of oxygen demanded by the muscle, leading to increased capillary perfusion and rising oxygen tension.

Evaluation of TEOAE and DPOAE measurements for the assessment of auditory thresholds in sensorineural hearing loss

Transiently evoked otoacoustic emissions (TEOAE) and distortion product otoacoustic emissions (DPOAE) can be quantified concerning their amplitude and frequency. They are known to be diminished or absent in sensorineural hearing loss. It is therefore of interest how TEOAE and DPOAE correlate with the auditory threshold and whether the auditory threshold can be predicted by these variables. In a cross sectional study of 61 patients (102 ears) with sensorineural hearing loss, auditory threshold, tympanometry, stapedius reflexes, TEOAE and DPOAE were measured. Correlation coefficients of the hearing loss (0.5-6 kHz) and the amplitude of the distortion product 2f1-f2 (0.46 4 kHz) respectively TEOAE amplitude (1-4 kHz) were computed. TEOAE showed lower correlation coefficients and less frequency specificity than DPOAE. In order to increase the correlations with the auditory threshold we fitted a multivariate linear regression model with TEOAE and DPOAE simultaneously as predictors for the auditory threshold gaining 95% prediction intervals of 19-39 dB depending on the frequency investigated. By restricting the hearing loss to a maximum of 70 dB HL the 95% prediction interval of the auditory threshold could be decreased to 18-26 dB. Further improvements can be expected if the high inter- and intraindividual variability of TEOAE and particularly DPOAE measurements can be reduced. The results allow us to use TEOAE and DPOAE in addition to click-evoked brainstem audiometry in order to provide more frequency specific information about the hearing loss in newborns, which is of the utmost importance for an ideal fitting of hearing aids.

[A new method for measuring internal ear circulation using colored microspheres]

The pathogenesis of sudden hearing loss is as yet unknown. Vascular disturbances are thought to play a major role, but they cannot be diagnosed clinically. We have therefore developed an animal model which allows measurements of the cochlear blood flow (CBF) and function. For CBF measurements a new technique based on coloured microspheres was developed. New Zealand rabbits were anaesthetised, ventilated and blood pressure and heart frequency were continuously monitored. 6 x 10(6) microspheres of one colour were injected in the left ventricle; different colours are available and allow multiple measurements. The amount of microspheres trapped in the capillary bed of the cochlea depends on the regional blood flow. An arterial reference blood sample makes it possible to calculate absolute values of the regional blood flow in the cochlea. The amount of microspheres trapped in the cochlea was determined microscopically after dissecting, dissolving and filtrating the cochlea. Measurements of the CBF in a control group (5 rabbits, 10 inner ears) at the beginning and after 120 minutes were performed. Mean CBF was 3.8 +/- 1.1 microliters/min and 4.3 +/- 1.3 microliters/min. The coloured microsphere technique allows repeated measurements of the CBF with good reproducibility and an acceptable standard deviation. CBF can be measured in absolute values, which is of advantage for determining a lower limit of the CBF for the cochlea function.

Immunohistological studies of complement activation after xenogeneic perfusion of a working heart model

Transplantation of organs from one species to another leads to immediate hyperacute rejection. Activation of complement is one important factor involved in this process. Whether complement activation is induced by preformed natural antibodies (PNAbs) via the classical pathway or by an "activator surface" via the alternative pathway is unclear. In order to simulate the relevant clinical situation of animal donor/human recipient we perfused working porcine hearts ex vivo with human blood. This also offered the possibility to study the process of complement activation in a precisely defined system with human complement proteins. PNAb titer and complement lytic activity of the plasma were measured. Immunohistological stainings for IgG, IgM, C1q, C4, C3d, C5-9, factor B, and properdin were performed on tissue sections of the left ventricle. PNAb titer almost totally disappeared within the first 5 min of perfusion. Complement lytic activity of the classical pathway decreased similarly within the first 3 h of xenogeneic and autologous perfusion from 70% to 40%. More detailed immunohistological studies revealed positive staining for C3d on endothelium and myocardium of ex vivo perfused xenogeneic hearts. Complement-induced cytotoxicity was proven by the presence of C5-9 (membrane attack complex). However, hardly any C1q and C4 could be found in the ex vivo xenogeneic perfused hearts. Staining for factor B was positive and proved activation via the alternative pathway. Beyond that, the presence of properdin binding even indicated an upregulation of the alternative pathway C3 convertase.(ABSTRACT TRUNCATED AT 250 WORDS)

Evolutionary and immunological aspects of xenotransplantation

Immunological aspects in xenotransplantation are directly linked to evolutionary aspects. The immunological network with its high antigen specificity and species-specific interactions was developed to fight against the host's outside world including xenografts. The tremendous amount of reaction and mechanisms triggered by the performed natural antibody-endothelial cell reaction clearly indicates that only basic changes might overcome these problems. Even the introduction of transgenic donors might not be sufficient to modify more than one parameter, for example, complement activity. Total depletion of preformed natural antibodies is not compatible with normal life and the regulation of hormones and enzymes under xenogeneic conditions has just been discovered. Cellular mechanisms depend, as far as we know, on the delicate system of receptors, interleukins, and MHC antigens. From today's very early results we know that major changes exist already between closely related species. The investigation of xenogenic mechanisms has opened a totally new field of immunological interactions. Up to now there are no signs of solution to bridge clinically relevant times with xenogenic organs from widely divergent suitable donors with promising quality of life.

[Tissue pO2 measurement in taut back musculature (m. erector spinae)]

Measurements with polarographic needle probes in fibromyalgic muscles (mm. erectores spinae) revealed an elevated mean tissue-pO2. The total mean tissue-pO2 in the patient group was significantly higher than that in the control group. Greater pathological tension in fibromyalgic muscles increases the mean tissue-pO2. The distribution of local tissue-pO2 values was normal; there was no evidence of small hypoxic areas in the muscle. The elevated tissue-pO2 in fibromyalgic muscles could either be explained by an increase in local blood flow or by disturbance of oxygen-utilization of the muscle cells. The mean tissue-pO2 in patients treated with NSAD was lower than in patients without this treatment. Myogelosises (i.e., circumscript tautness in muscles, that, contrary to fibromyalgic muscles, do not relax under general anesthesia) showed low tissue-pO2 values and even hypoxia in the core. In myogelosises, pain could be hypoxic in nature. However, in fibromyalgic muscles no evidence for hypoxia or hypoxia-related pain could be found.