PubMed Health⌕ Search

Biomedical subjects

J Helms

Publications and source records attributed to J Helms.

At least 37 records · Page 2Linked to original sources

[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.

Adenocarcinoma↗

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.

Acoustic Stimulation↗

[Inner ear depression after middle ear interventions].

BACKGROUND: Any type of otosurgical procedure involves the risk of inner ear damage. As middle ear surgery is also performed for functional reasons this risk should be taken into consideration. The aim of this study was to analyse the frequency and the nature of sensorineural hearing loss following chronic ear surgery. PATIENTS: A total of 3989 middle ear cases operated on between 1991 and February 1999 at the Department of Otorhinolaryngology, Head and Neck Surgery, University of Würzburg, Germany were studied retrospectively: 781 type I tympanoplasties, 2408 type III tympanoplasties and 800 cases of stapes surgery. The pre- and the postoperative audiograms in the frequency range between 500 and 8000 Hz were analysed and correlated to the different intraoperative findings. RESULTS: Sensorineural hearing loss occurred in a total of 1.3% of 2224 patients with normal preoperative bone conduction thresholds: 0.2% became deaf, 0.8% acquired a high tone loss at 4 kHz and in 0.3% patients also 2 kHz was affected. None of the documented intraoperative complications such as bleeding, unexpected opening of a semicircular canal, extensive manipulation at the ossicular chain or a gusher phenoma showed a relevant effect on postoperative bone conduction thresholds. The incidence of high tone loss was not increased in cases of extensive drilling of the temporal bone. An unexpected opening of the vestibulum led to a small, but statistically significant change in postoperative bone conduction thresholds. CONCLUSIONS: Our results demonstrated that the risk for sensorineural hearing loss caused by middle ear surgery is low. None of the analysed factors seems to be a relevant prognostic risk factor for postoperative inner ear depression.

Adolescent↗

["Vibrant Soundbridge" middle ear implant for auditory rehabilitation in sensory hearing loss. I. Clinical aspects, indications and initial results].

BACKGROUND: The adequate therapy for patients suffering from a sensory hearing loss consists of fitting electronic hearing devices. Conventional hearing aids, however, present with significant inherent drawbacks such as insufficient amplification in the high frequency range, problems with the ear mold (feed back, occlusion, external otitis), or distortion of sound with an "unnatural" hearing impression. METHODS: The partially implantable middle ear device Vibrant Soundbridge provides a sound wave conversion into mechanical vibrations at the middle ear ossicles using the Floating Mass Transducer (FMT). The audiological advantages are due to a direct moving force to the perilymph via incus and stapes. The Vibrant Soundbridge system is indicated in patients with a medium to severe symmetrical sensory hearing loss and a normal middle ear. Candidates need previous experience with conventional hearing aids without satisfactory results. RESULTS: The eight operated patients report a "natural" quality of sound and speech, a better hearing perception at high frequencies and the absence of feed back phenomena. Audiological evaluation and questionnair results support the patients subjective hearing impression. CONCLUSIONS: The Vibrant Soundbridge improves hearing quality in patients with sensory hearing loss. The hearing implant is indicated in particular in patients that are unable to wear conventional hearing aids.

Adult↗

[Universal hearing screening of newborn infants with the BERA-phone].

BACKGROUND: Unidentified and untreated early infant hearing loss leads to speech-language deficits as well as to cognitive, intellectual, emotional and psychosocial handicaps. Targeted hearing screening programs may miss approximately 50% of all hearing impaired children. METHODS: In an universal hearing screening program with a two stage protocol, 1349 newborns were examined using the CRESCENDO Newborn Hearing Screener according to Finkenzeller and a clinical ABR system operating with a time course step stimulus algorithm. RESULTS: Five newborns that failed the two stage screening protocol were diagnosed as hearing impaired so that therapy was initiated before the age of six months. The specificity of the method was 98.8%. The CRESCENDO method only required a short examination time and was easy to apply. CONCLUSIONS: Hearing screening programs using ABR offer advantages when compared to evoked otoacoustic emission testing. ABR threshold detection with the time course step stimulus algorithm is a quick and easy to apply method with high specificity that can be recommended for newborn hearing screening.

Algorithms↗

Quantitative parameters of intraoperative electromyography predict facial nerve outcomes for vestibular schwannoma surgery.

OBJECTIVE: Facial nerve monitoring is an established method that is routinely used during cerebellopontine angle tumor surgery. The aim of this study was to determine quantitative electromyographic (EMG) parameters that were predictive of facial nerve outcomes. METHODS: In 137 patients with intra-/extrameatal vestibular schwannomas, the most proximal (the exit from the brainstem) and distal (the fundus of the internal auditory canal) parts of the facial nerve were stimulated after total tumor removal. A quantitative analysis of absolute values and ratios (proximal/distal) of evoked EMG parameters (amplitude, latency, and duration) was performed, and parameters were correlated with postoperative (1 and 6 wk and 6 mo) facial nerve function (FNF). RESULTS: Absolute values of EMG amplitudes were statistically correlated with FNF (P < 0.05). Amplitude ratios (proximal/distal) demonstrated an even greater predictive power. The risk of exhibiting facial palsy 6 months after surgery increased from 1.6% (amplitude ratio of >0.8) to 75% (ratio of <0.1). For EMG latencies, only the ratios revealed a significant correlation with FNF. The latency ratio-dependent risk of facial palsy after 6 months increased from 2.9% (ratio of <1.05) to 33% (ratio of >1.35). The durations of the muscle responses were not significantly correlated with clinical outcomes. CONCLUSION: The predictive power of the amplitudes and latencies of electrically evoked muscle responses could be improved by calculating proximal/distal ratios. The proximal/distal amplitude ratio proved to be the most powerful parameter for intraoperative assessment of postoperative FNF.

Adult↗

Acoustic neuroma surgery as an interdisciplinary approach: a neurosurgical series of 508 patients.

OBJECTIVES: To evaluate an interdisciplinary concept (neurosurgery/ear, nose, and throat (ENT)) of treating acoustic neuromas with extrameatal extension via the retromastoidal approach. To analyse whether monitoring both facial nerve EMG and BAEP improved the functional outcome in acoustic neuroma surgery. METHODS: In a series of 508 patients consecutively operated on over a period of 7 years, functional outcome of the facial nerve was evaluated according to the House/Brackmann scale and hearing preservation was classified using the Gardner/Robertson system. RESULTS: Facial monitoring (396 of 508 operations) and continuous BAEP recording (229 of 399 cases with preserved hearing preoperatively) were performed routinely. With intraoperative monitoring, the rate of excellent/good facial nerve function (House/Brackmann I-II) was 88.7%. Good functional hearing (Gardner/Robertson 1-3) was preserved in 39.8%. CONCLUSION: Acoustic neuroma surgery via a retrosigmoidal approach is a safe and effective treatment for tumours with extrameatal extension. Functional results can be substantially improved by intraoperative monitoring. The interdisciplinary concept of surgery performed by ENT and neurosurgeons was particularly convincing as each pathoanatomical phase of the operation is performed by a surgeon best acquainted with the regional specialties.

Adolescent↗

[Selection of a cochlear implant and results of implantation].

BACKGROUND: The cochlear implant is the therapy of choice for completely deaf patients. With this concept speech communication can be restored or developed. METHODS: The selection of the implant system may depend on different factors. As long as speech competence is thought to be of highest importance, a fast stimulation strategy involving a state of the art cochlear implant that provides 1500 Hz for every single electrode is close to the optimum. Further parameters include deep insertion into the cochlea (normally 30 mm) and other technical details. RESULTS: With these conditions fulfilled, about 2/3 of the adult deaf patients will later be able to use a telephone. Children who received implants in due time and do not have other cerebral defects will be partly able to meet with the requirements of normal schools.

Adolescent↗

Technical developments in intra-operative monitoring for the preservation of cranial motor nerves and hearing in skull base surgery.

Although EMG recordings from mimic muscles have become the standard for intra-operative facial nerve monitoring, few data are available concerning other motor cranial nerves (MCN). Auditory brainstem responses (ABR) are a proven tool for intra-operative hearing preservation, but have their limitations, suggesting the application of supplementary methods. This paper describes new developments of MCN and cochlear nerve monitoring in skull base surgery. Up to 2 x 8 EMG channels were recorded after bipolar stimulation of MCN using concentric coaxial probes. A special software enabled event-dependent registrations of all signals exceeding a definable threshold level. Selective recordings from masticatory muscles (N.V) were obtained using rectangular Teflon-insulated needle electrodes. For oculomotor (Nn.III/ VI) nerve recordings bipolar needle electrodes were precisely placed by orbital ultrasound guidance. Lower cranial nerves were monitored inserting needle electrodes into the soft palate (N.IX), tongue (N.XII) and vocal muscles (N.X) during laryngoscopy using a special applicator. For ABR recordings, click stimuli (95 dB HL) were applied monaurally through insert earphones. Electrocochleography was simultaneously recorded as a near-field potential without averaging after promontory (transtympanic) electrode placement using otomicroscopy. Regarding the ABR biosignal, a characteristic response pattern was detected following bipolar electrical stimulation of the auditory nerve possibly useful for its intra-operative identification.

Cochlear Nerve↗