Frequent detection of Mycoplasma pneumoniae in Bell?s palsy

The cause of Bell's palsy (BP) remains unknown despite various hints to an infectious etiology. Mycoplasma pneumoniae is a common pathogen of the respiratory tract causing pharyngitis, tracheobronchitis or pneumonia. Neurological complications are the most frequent extrapulmonary manifestation. So far, only a few case reports suggested an association between cranial nerve palsy and M. pneumoniae infection. Patients with a BP who were admitted to the Department of Otorhinolaryngology or Neurology of the University of Wuerzburg between 2000 and 2002 were tested serologically for the presence of antibodies against Borrelia burgdorferi, herpes viruses (HSV-1/2, VZV) and M. pneumoniae. The diagnosis of mycoplasmal infection was made when at least one of the following criteria was met: a threefold rise or more in the titer of antibody of M. pneumoniae in paired sample or a microparticle agglutination assay (MAG) of > or =1:40 and the detection of IgA and/or IgM antibodies in the acute phase serum. Ninety-one consecutive patients could be included. Fifteen patients showed a reactivation of a VZV ( n=12) or of a HSV-1 ( n=3) infection. In six cases the immunoblot revealed specific antibody bands for B. burgdorferi. In 24 patients (26.4%) a seroconversion of M. pneumoniae could be detected. Only two patients complained of mild respiratory symptoms. According to our results, M. pneumoniae is frequently associated with Bell's palsy. Thus, a routine screening for this pathogen, even in the absence of respiratory symptoms, is necessary.

[Long term results after cochlear implantation in elderly patients]

BACKGROUND

Cochlear implantation has become the method of choice for the treatment of deaf patients. A better technology of stimulation opened a wider field of patients suitable for cochlear implantation. Aim of the present study was to evaluate to which extent senior patients benefit by cochlear implantation.

PATIENTS AND METHODS

36 patients between 65 and 85 years were tested by the Freiburger speech test for monosyllabic words and by the HSM sentence test with and without noise. The results were compared to those of younger implanted patients (16 - 64 years, n = 101).

RESULTS

The speech perception for monosyllabic words did not differ significantly between both groups. A maximum plateau in speech perception for monosyllabic words was reached after 2 years at 55 %. The HSM sentence test revealed significant differences in the increase of speech perception between senior and younger patients in the first post surgical year. After one year elderly patients reached the same perception score as younger patients with a maximum of approximately 80 % after 3 years. At a signal to noise ratio of 15 % younger patients achieved a maximal perception of 55 % after 1 year whereas senior patients needed 4 years to reach this level.

CONCLUSIONS

Senior patients benefited by cochlear implantation to the same extent as younger patients did. Senior patients gained a similar speech perception level as younger implanted patients although the elderly needed more time to reach the same scores. Nevertheless, cochlear implantation should not be denied due to age alone.

[Experimental investigations of CO2 laser application in middle ear ossicles]

BACKGROUND

During the last few years, several laser systems have been applied for procedures in middle ear surgery. In this study, we determined the technical parameters for the dissection of the middle ear ossicles with the CO(2) laser and analyzed the histological findings.

METHODS

The malleus necks of 16 human temporal bones were dissected under standardized conditions using a CO(2) laser with a power output between 35 and 55 kW/cm(2). The specimens were fixed and histological probes of 50- micro m thickness were prepared.

RESULTS

The laser outputs led to crater diameters from 0.14 to 0.55 mm. As an analogy between laser energy and thermal tissue destruction, three zones of thermal damage were differentiated: a cinder zone, a carbonization zone, and a zone of dehydration. The metrical dimensions of these zones did not show any correlation to the applied laser energy.

CONCLUSIONS

The data of this study show that commercially available CO(2) lasers are sufficient for a safe and effective partial resection of middle ear ossicles using a power output of 35 kW/cm(2).

Meningitis following cochlear implantation: pathomechanisms, clinical symptoms, conservative and surgical treatments

Pneumococcal otogenic meningitis is a rare postsurgical complication that can develop following stapedectomy or after cochlear implantation. The bacterial infection can be fatal in some instances. A recent increase in the incidence of otogenic meningitis among cochlear implant wearers is of concern. The majority of meningitis cases are associated with a 2-component electrode manufactured by one cochlear implant company. The device with the added 'positioner' component has been withdrawn from the market (FDA Public Health Web Notification: Cochlear Implant Recipients may be at Greater Risk for Meningitis, Updated: August 29, 2002, www.fda.gov/cdrh/safety/cochlear.html). Not all cases have been subsequent to otitis media and symptoms have developed from less than 24 h up to a few years after implantation. The purpose of this paper is to review and discuss the pathogenesis, pathology/bacteriology and to elaborate on some clinical features of otogenic meningitis in implanted children and adults. Essential aspects of surgery, electrode design, and cochleostomy seal are discussed. Conclusions are drawn from the available data and recommendations are made for good practice in cochlear implantation and follow-up.

Speech understanding in quiet and noise in bilateral users of the MED-EL COMBI 40/40+ cochlear implant system

OBJECTIVE

The purpose of the study was to investigate speech understanding in quiet and noise in subjects bilaterally implanted with multi-channel cochlear implants.

DESIGN

Nine adults bilaterally implanted with MED-EL implants were included in the study. The subjects were tested in three conditions: with both implants, with the right implant only, and with the left implant only. Speech tests included monosyllables in quiet and sentences in noise (10 dB signal to noise ratio). Speech was presented from the front, and noise was presented from either 90 degrees or 270 degrees azimuth.

RESULTS

All subjects reported benefit from bilateral stimulation. Speech scores for all subjects were higher with bilateral than with unilateral stimulation. The average score across subjects for sentence understanding was 31.1 percentage points higher with both cochlear implants compared with the cochlear implant ipsilateral to the noise, and 10.7 percentage points higher with both cochlear implants compared with the cochlear implant contralateral to the noise. The average score for recognition of monosyllabic words was 18.7 percentage points higher with both cochlear implants than with one cochlear implant. All of these differences in average scores were significant at the 5% level.

CONCLUSIONS

Bilateral cochlear implantation provides a significant benefit in speech understanding in both quiet and noise.

[The Würzburg questionnaire for assessing the quality of hearing in CI-children (WH-CIK)]

BACKGROUND

The goal of this study was to compare the auditory behaviour of bilaterally implanted children while using both CIs to their auditory behaviour during the time when they were using one CI.

METHODS

For this purpose a questionnaire looking at different aspects of hearing such as hearing in background noise, in complex listening situations and directional hearing was developed. The questionnaire was completed by the parents of 28 bilaterally implanted children. They were instructed to state their judgement on the behaviour of their children. The parents scaled their judgements using a method of extended category scaling similar to that applied in the loudness scaling with the Würzburg hearing field (WHF). Each of the five verbal categories was subdivided into 10 numerical subdivisions, so that the parents were able to express judgements lying between the different categories.

RESULTS

Eight out of eleven items showed that hearing with bilateral CIs was significantly better than with one CI (p < 0,003). The two items, which did not show a significant difference between the two conditions were those related to the interest in auditory rehabilitation and to aversion to noise.

CONCLUSIONS

The questionnaire has proven to be a useful instrument to assess the quality of hearing in children. The possibility of bilateral implantation should be considered during the decision process prior to implantation.

Clinical experience with the Vibrant Soundbridge implant device

OBJECTIVE

To evaluate the full degree and range of benefits provided by the Vibrant Soundbridge (VSB; Symphonix Devices, Inc., San Jose, CA, U.S.A.) and analyze pre-and postoperative results of audiologic tests.

STUDY DESIGN

Single-subject study with each subject serving as his or her own control.

SETTING

Multicenter clinical study conducted at 10 centers in Europe.

PATIENTS

47 patients who met the selection criteria for participation in the study.

INTERVENTIONS

Implantation of the VSB direct-drive middle ear hearing device.

MAIN OUTCOME MEASURES

Average change in unaided thresholds with the patient wearing headphones at each frequency pre-and postsurgery was measured. A mean threshold change less than 5 dB across all frequencies was considered clinically nonsignificant.

RESULTS

47 patients had successful surgery for implantation and fitting with the VSB device.

CONCLUSION

The VSB is a new middle ear implant device that can be used safely in the treatment of patients with moderate to severe sensorineural hearing loss.

Combined intra-operative monitoring of hearing by means of auditory brainstem responses (ABR) and transtympanic electrocochleography (ECochG) during surgery of intra- and extrameatal acoustic neurinomas

BACKGROUND

Although being established as a standard procedure in intra-operative monitoring in acoustic neurinoma surgery, auditory brainstem responses (ABR) represent a far-field technique bearing some technical limitations. This prospective study was designed to evaluate electrocochleography (ECochG) as a supplementary tool for hearing preservation.

METHOD

84 patients with unilateral intra-/extrameatal acoustic neurinomas (extrameatal diameter: 5-55 mm) preserving serviceable hearing, were operated on using a combined (neuro-/otosurgical) suboccipital approach. ECochG was recorded simultaneously to ABR following transtympanic insertion of a steel needle electrode into the promontory under otoscopic view.

FINDINGS

Serviceable hearing (Class 1-3 according to Gardner/Robertson) was preserved in 43 out of 84 patients (51.2%), of whom 40 showed both ECochG and ABR being preserved. All 24 patients with loss of both modalities became deaf. Hearing preservation was observed in 4 out of 12 patients with preserved ECochG but loss of ABR (waves III-V). The reverse was observed in 2 cases with postoperative deafness. While both ECochG and ABR amplitudes were significantly correlated with pre- and postoperative hearing, latencies of ECochG summating (SP) and action potential (AP) proved to be more reliable indicators for preserved hearing than ABR (peak I/III/V) latencies. The predictive value of baseline ABR amplitudes for postoperative hearing, however, was superior to ECochG parameters. Only in large neurinomas (extrameatal diameter: >2 cm) tumour size was found to be a significant predictor for the preservation of hearing. Apart from three cases with postoperative otoliquorrhea and one further case presenting with local bleeding within the external acoustic meatus, no side effects were observed.

CONCLUSIONS

In combination with ABR monitoring, ECochG proved to be a useful supplementary tool for hearing preservation in acoustic neurinoma surgery. It is particularly helpful during electrocautery and drilling, since no averaging is required. Special applications are: (1) small tumours with good serviceable hearing; (2) and/or a large intrameatal portion; (3) cases with lost or endangered contralateral hearing (e.g. bilateral acoustic neurinomas), when the preservation of poor or even non-functional hearing is desirable.

[Diagnosis, treatment and results of malignant skull base tumours]

BACKGROUND

Malignant tumours of the cranial base are rare and present usually in advanced tumour stage due to the lack of early clinical symptoms.

PATIENTS AND METHODS

Sixty patients with malignant tumours infiltrating the skull base were treated at the Department of Otorhinolaryngology Head and Neck Surgery, University of Würzburg between 1987 and 1999. Most of the tumours (n = 51) originated from the nose or paranasal sinuses, the epipharynx, the outer ear canal or the middle ear. Seven tumours were malignant brain tumours infiltrating the bony structures of the skull base or originated from the cranial base itself. Two patients suffered from metastases of an adenocarcinoma of the prostata. The histological diagnosis was confirmed in 53 patients preoperatively and in seven patients during tumour resection. Squamous cell carcinoma (n = 24), adenocarcinoma (n = 10) and sarcoma (n = 7) were the most common histologies found.

RESULTS

A radical en bloc resection of the tumour was only possible in 26 out of 60 cases. A surgical tumour reduction with postoperative radiation therapy was performed in seven patients as a palliative approach. Eight patients underwent a combined radio- and chemotherapy according to the histological diagnosis. Primary radiotherapy was the treatment of choice in eleven patients, where the tumours were located in the central area of the cranial base. Palliative radiotherapy or solely medical pain control were applied to eight patients who presented either with distant metastases or an advanced tumour growth. The mean postoperative survival following radical surgery was 48 months and after primary radiotherapy 27 months.

DISCUSSION

A statistical analysis of the results is not applicable due to the great variety of the disease concerning the histological diagnosis, the tumour size and the location as well as the small number of patients.

Intra-operative electromyographic monitoring of the lower cranial motor nerves (LCN IX-XII) in skull base surgery

The functional preservation of lower (motor) cranial nerves (LCN) is endangered during skull base surgery. Intra-operative EMG monitoring of the LCN IX-XII was investigated in 78 patients undergoing 80 operations on various skull base tumors with regard to technical feasibility and clinical efficacy. Ongoing 'spontaneous muscle activity' (SMA) and 'compound muscle action potentials' (CMAP) following supramaximal bipolar stimulation were intra-operatively recorded applying needle electrodes into the soft palate (CN IX: n=76), the vocal cord (CN X: n=72), the trapezius muscle (CN XI: n=18), and the tongue (CN XII: n=71). From 24/22/8 cases with LCN IX/X/XII deficits (despite monitoring) only 5/6/4 remained unchanged (3-6 months postoperative). An irreversible plegia of the LCN IX/X/XII occurred in three (1/1/1) patients. In 7/6/1 patients postoperative (3-6 months) LCN IX/X/XII function was better than preoperatively. In all patients accessory nerve function remained unchanged. 'Pathological' SMA of the LCN IX/X/XII occurred in 12/16/8 cases, but in only 6/5/3 cases corresponded to postoperative LCN deficits. Corresponding 'pathological' SMA patterns were found in 18/17/5 out of 24/22/8 cases with postoperative LCN IX/X/XII dysfunction. Reproducible CMAP of LCN IX/X/XI/XII could be recorded in 59/56/11/32 patients. Approximate 'normal' values were calculated and compared to (very few) data so far given in the literature. Electromyographic monitoring proved to be a safe tool for the intra-operative identification and localization of the LCN contributing to their anatomical and functional preservation. The predictive value of standard neurophysiological parameters for functional outcome, however, is limited.

[Detection of loudness recruitment in patients with retrocochlear lesions using the "Würzburger Hörfeld" loudness scaling]

BACKGROUND

The pathogenesis of hearing loss caused by cerebellopontine angle tumors such as acoustic neuromas is unknown. The lack of loudness recruitment is thought to be one of the features of retrocochlear hearing impairment. In contrast to conventional suprathreshold tests, the categorial loudness scaling using the "Würzburger Hörfeld" is a valuable tool to describe the individual perception of sound. The aim of the present study was to analyze the loudness growth rate in patients with acoustic neuroma.

PATIENTS AND METHOD

Pure tone and speech audiometry as well as auditory brainstem response and bilateral categorial loudness scaling were performed preoperatively in 54 patients with acoustic neuroma. Loudness scaling was done in free field switching off the contralateral ear by using an ear-plug.

RESULTS

An abnormal rapid loudness growth function was found in 38 of the 54 patients (70.4%) at least at one frequency on the tumor side. The contralateral side was effected only in 57.4% of the patients. The incidence of a recruitment depended on the frequency with a maximum at 4 kHz. The slope of the loudness function showed a tendency to increase with increasing hearing loss.

CONCLUSIONS

Loudness recruitment is not a rare phenomenon in patients with acoustic neuroma. The underlying cause (a preexisting hair cell damage, hair cell changes resulting from an obstruction of the cochlear blood supply or a disruption of the cochlear efferents) still remains unclear.

Organ culture of craniofacial primordia

Organ culture systems have proven extremely useful techniques in studies that investigate the process of normal and abnormal development. The explant of tissues into an organ culture system is one of the few techniques that maintains three-dimensional cellular interactions under conditions that simultaneously permit controlled experimental manipulation in vitro. In this article we outline a procedure for growing "faces" in culture. In this system, the facial primordia prepared from embryonic mice or chicks can be maintained in culture for up to 7--8 days. During this time, the facial primordia continue to grow, differentiate, fuse and develop into organized structures that closely resemble those observed in situ. The procedure is relatively simple, requiring only a stable substratum, culture medium, sufficient oxygenation and incubation of the organ system at 37 degrees C. The advantages and disadvantages of the procedure are presented, along with detailed methods to help troubleshoot some of the common pitfalls of organ culture systems.

Comparison of the TEMPO+ ear-level speech processor and the cis pro+ body-worn processor in adult MED-EL cochlear implant users

A study was conducted to compare the new MED-EL TEMPO+ ear-level speech processor with the CIS PRO+ body-worn processor in the COMBI 40/COMBI 40+ implant system. Speech tests were performed in 46 experienced subjects in two test sessions approximately 4 weeks apart. Subjects were switched over from the CIS PRO+ to the TEMPO+ in the first session and used only the TEMPO+ in the time between the two sessions. Speech tests included monosyllabic word tests and sentence tests via the telephone. An adaptive noise method was used to adjust each subject's scores to approximately 50%. Additionally, subjects had to complete a questionnaire based on their 4 weeks of experience with the TEMPO+. The speech test results showed a statistically significant improvement in the monosyllabic word scores with the TEMPO+. In addition, in the second session, subjects showed a significant improvement when using the telephone with the TEMPO+, indicating some learning in this task. In the questionnaire, the vast majority of subjects found that the TEMPO+ allows equal or better speech understanding and rated the sound quality of the TEMPO+ higher. All these objective and subjective results indicate the superiority of the TEMPO+ and are mainly attributed to a new coding strategy called CIS+ and its implementation in the TEMPO+. In other words, based on the results of this study, it appears that after switching over from the CIS PRO+ to the TEMPO+, subjects are able to maintain or even improve their own speech understanding capability.