The use of the covered Wallstent for the palliative treatment of inoperable tracheobronchial cancers. A prospective, multicenter study

STUDY OBJECTIVE

To investigate the safety, efficacy, and tolerance of the covered Wallstent for the palliative treatment of inoperable tracheobronchial cancer.

DESIGN

An 8-month prospective study employing either a rigid bronchoscope or a flexible delivery system for prosthesis insertion.

SETTING

Multicentric setting involving four teaching hospitals in Switzerland and Germany.

PATIENTS

Forty patients (29 men, 11 women), average age of 62 years, presenting with an inoperable tracheobronchial cancer.

INTERVENTIONS

After partial airway recanalization with an Nd-YAG laser, the covered Wallstent was inserted 23 times using a rigid bronchoscope (Rigidstep device), and 27 times using a flexible delivery system (Telestep device) under fluoroscopic and endoscopic visualization.

RESULTS

Clinical and endoscopic examination at 1, 30, and 90 days showed improvement in the bronchial lumen and in the dyspnea index. No serious complication (death, perforation, hemorrhage, inability to remove an improperly placed prosthesis) was observed during surgery. Late complications included migration (12%), inflammatory granulations or tumor regrowth at the tip of the prosthesis (36%), and symptomatic retention of secretion (38%).

CONCLUSIONS

Compared with other tracheobronchial prostheses, notably the Dumon stent, the covered Wallstent presents the following advantages: insertion with visual guidance, treatment of extrinsic compressions and esophagobronchial fistulas, and little chance of migration when the prosthesis diameter is chosen correctly. The following disadvantages can be noted: high price; both repositioning and extraction of the released stent are more difficult, though certainly possible; and risk of granulations at the tips of the prosthesis and retention of secretions. Suggestions are made for potential improvements to the stent and insertion system that may result in a significant decrease in early and late complications.

Different aspects of hearing preservation in surgery of vestibular schwannoma in women and men

Pre-operative and postoperative auditory function was reviewed retrospectively in 98 patients with vestibular schwannomas. According to their hormonal status, women were categorized as "premenopausal" and "postmenopausal". Before surgery, 48% of the women (65% premenopausal) and 16% of the men presented with sudden hearing loss. The degree of auditory function before operation was similar for women and men. Preservation of pre-operative hearing was possible for 41% of the women (21% premenopausal) and 59% of the men. Further details of the surgery and the results of histopathological examination were also compared for women and men. Our results support substantial evidence that hearing preservation after surgery of vestibular schwannoma is easier to accomplish for men than for women. The finding of significantly more sudden hearing loss in premenopausal women may suggest a hormonal influence on tumour growth, which may also be partially responsible for the difference in hearing prognosis between women and men.

An Airway Wallstent for the treatment of tracheobronchial malignancies

BACKGROUND

The palliative effect of a new Airway Wallstent with a polyurethane covering was tested in patients with inoperable malignant lesions of the central airways.

METHODS

Thirty six stents were inserted in 27 patients with obstruction (n = 24) or fistulae (n = 3), 15 of whom later received radiotherapy. The degree of symptom relief was assessed 1, 30, and 90 days after stent insertion.

RESULTS

Stent deployment was successful in all patients. Significant improvements were observed one day after placement compared with before placement, with no change at 30 and 90 days, in dyspnoea index (mean (SD) 3.2 (0.7) before stent insertion compared with 1.8 (0.7) one day after insertion); Karnofsky index (32 (18) before insertion compared with 55 (15) one day after insertion); and obstruction of airway diameter (85 (11)% before insertion compared with 10 (12)% on day 1 after stent insertion). Stent-related complications needing later interventions included retained secretions (five patients), granuloma formation at ends of the stent (four patients), and stent migration (four patients). Over a median observation period of two months (range two days to 8.5 months) all stent coverings remained intact without delamination or tumour ingrowth.

CONCLUSIONS

The Airway Wallstent provided excellent palliation for malignant obstructions and fistulae of the central airways. Retention of secretions and granuloma formation at the ends of the stent warrant minor technical improvements.

[Multiple biopsy in diagnosis of laryngeal carcinoma]

BACKGROUND

The fate of patients suffering from laryngeal carcinoma is influenced strongly by the stage of the tumor at the time of diagnosis. This factor is also critical for preservation of the organ. It may be impossible to diagnose the tumor with the first biopsy even though the clinical and macroscopic aspect suggests a malignancy.

METHODS

In a retrospective study, we examined 468 patients with laryngeal carcinoma who were treated at the departments of otorhinolaryngology at the University of Basel (B) (198 patients from 1983-1992) or in Giessen (G) (270 from 1990-1995). The number of biopsies necessary to confirm the diagnosis was analysed and the follow-up of the patients was evaluated. Thirty of 32 negative histologic samples were reexamined.

RESULTS

Of 468 patients, 32 (7%, 27 [B] 14%; and 5 [C] 2%) required two to six biopsies to confirm the clinically suspected diagnosis: Twenty patients (designated as Group 1) were diagnosed within one to three months, and no patient showed a change of tumor stage within that time. Their first biopsies have to be considered as "nonrepresentative". Eight patients (Group 2) were diagnosed within four to 24 months and four patients (Group 3) more than 24 months after the first biopsy. Final treatment and outcome in patients from Group 1 was unchanged by the time delay in diagnosing the tumor. Seven of eight patients in Group 2 experienced an obvious progression of their tumor during the diagnostic period, which led to laryngectomy in several cases. In four patients, diagnosis was confirmed more than two years after the first biopsy. These were special cases such as development of cancer out of a papillomatosis or chronic laryngitis.

CONCLUSIONS

A time delay of three months in diagnosing cancer of the larynx does not have a significant influence on organ preservation and prognosis, even though especially in small tumors suspicion of cancer should lead to a new representative biopsy as fast as possible to preserve the larynx.

[Hearing handicap--an addition to audiometric hearing loss. Results of an exploratory study of auditory communication disorders in the elderly]

Hearing problems in elderly patients cannot be evaluated completely with conventional audiological tests in most cases. Two hundred and one subjects aged 60 years or more complaining of hearing problems were studied. The following tests were employed: pure-tone audiometry, the "Basler Satztest" (a German version of the SPIN-test assessing speech perception in noise), and a German version of a "Hearing Handicap Inventory for the Elderly" (HHIE). These latter versions were developed in our institution. An auditory handicap was found in one-third of subjects with mild hearing losses (PTA < 30 dB; n = 135) and in two-thirds of subjects with greater hearing losses (PTA > and = 30 dB; n = 65). The relatively weak correlations of the pure-tone audiogram (r = 0.49) or speech audiometry (r = 0.41) with HHIE indicate that more than 50% of the variance of the hearing handicap was due to non-audiologic factors. For this reason, we recommend that the handicap questionnaire be added to the audiometric evaluation.

Effect of otoacoustic emissions on just-noticeable differences for intensity in normally hearing subjects

Measurements of spontaneous and click-evoked otoacoustic emissions (OAEs) were used to classify listeners with normal hearing into one of two categories--those with spontaneous emissions (SOAEs) and high-level transiently evoked emissions (TEOAEs) in both ears (strong emissions) and those with no SOAEs and low-level TEOAEs in either ear (weak emissions). Just-noticeable differences (jnd's) in intensity for 1-kHz pure tones presented at either 60, 40, or 20 dB SL were determined for these two groups using a continuous pedestal technique. Mean jnd's for intensity for the two groups did not differ significantly. Intratest variability was compared and the group with strong emissions had significantly higher variability for presentation levels of 20 dB SL and lower variability at 60 dB SL. Additional testing of intensity jnd's was performed in individuals with strong emissions using pure tones 30 Hz lower than a targeted SOAE frequency. Large interindividual differences were present without a specific pattern. It is concluded that OAE activity level does not affect the mean jnd for intensity discrimination. Individuals with strong emissions have less variance when performing the test at higher levels and more variance for lower level stimuli than do individuals with weak emission characteristics. Because an ear's OAE characteristics can alter performance on psychoacoustic tasks, knowledge of such characteristics is desirable when psychoacoustic results are acquired and reported.

[3-year follow-up after endonasal microscopic paranasal sinus surgery in migraine and cluster headache]

BACKGROUND

Migraine and cluster headache can both be triggered by sensitive intranasal areas.

METHODS

Endoscopic nasal surgery was performed in 20 patients with chronic migraine without aura or cluster headaches that were refractory to other forms of treatment for a mean period of 18 years (range of 1-45 years). The selected patients showed clinical and radiographic evidence of contact between the middle turbinate and the nasal septum. All patients experienced immediate relief of pain following topical application of cocaine to the presumable triggering area. Five patients with cluster headache and 15 patients with migraine were treated.

RESULTS

All patients with cluster headache were free of symptoms after surgical intervention and for a mean follow-up period of three years. Six of the 15 patients with migraine were completely free of symptoms after a mean follow-up period of three years; five had improved more than 50% in the duration and frequency of their attacks. Treatment was unsuccessful in four patients.

CONCLUSION

This trial established a likely relationship between nasal trigger areas and cluster headache through the trigeminovascular system and a possible relationship to some type of migraine without aura.

[Reliability of the rapid Streptococcus A test]

The results of three second-generation immune assays for direct detection of group A streptococcus were compared in 65 patients with acute pharyngitis. The assays included Strep A Plus, (Abbott), Concise Strep A (Hybritech) and Cards Plus (Pacific Biotech). A standard culture was used as reference. Additionally a nucleic acid hybridization assay (Gen-Probe) was applied after enhanced broth culturing. The sensitivities and specificities of the three immunoassays were similar and showed that Strep A Plus had an 84.2% sensitivity and 88.9% specificity, Concise Strep A an 82.4% sensitivity and 92.3% specificity, and Cards Plus an 84.2% specificity and 90.7% sensitivity. The Concise Strep A had significantly more doubtful results in comparison with the two other rapid immune assays (9.7% versus 2.3%, P = 0.034. The standard culture and the DNA probe test gave the same results in 94% of cases. Clinical parameters were found to be unreliable for the diagnosis of group A streptococcal pharyngitis. However, findings show that when the rapid immune assay is positive, it is reasonable to start antibiotic treatment without performing a bacterial culture. In cases with a negative assay, management is best tailored to clinical symptoms and laboratory examinations.

[Transitory evoked otoacoustic emissions and distortion product emissions in disorders of middle ear ventilation]

Both the amplitude and power spectra of otoacoustic emissions are affected by the transfer properties of the middle ear. This prospective study examined the influence of eustachian tube dysfunction on transiently evoked otoacoustic emissions (TEOAEs) and distortion-product otoacoustic emissions (DPOAEs). In all, 18 ears were studied that exhibited negative middle ear pressures with or without middle ear fluid. Measurements were performed at the time of diagnosis during the recovery stage, and after the middle ear became normally ventilated. Findings showed that TEOAE and DPOAE levels increased while airbone gaps were reduced by an average of 8 dB after negative middle ear pressures returned from -400 daPa to a normal state. There was a tendency for negative middle ear pressure to affect DPOAEs more in the 1-kHz region than in higher frequencies. By contrast, TEOAEs and airbone gaps were more uniformly affected across the entire frequency range. These results for ears with eustachian tube dysfunction were somewhat different from those results of studies obtained in healthy ears tested during experimental changes in middle ear pressure.

[Computer-assisted surgery of the paranasal sinuses with an opto-electronic stereotaxic system]

BACKGROUND

A basic problem common to all systems for computer-assisted surgery (CAS) is the exact registration and referencing, that is, the transfer of preoperative image data to the intraoperative pathology. A system for computer-assisted ENT surgery should provide high precision as well as noninvasive registration and referencing. We present a system designed for such use in paranasal sinus surgery that is based on optical digitizing with several custom-made self-localizing surgical instruments.

METHODS AND RESULTS

The system tracks the correct alignment of the head during CT data acquisition and continuously throughout surgery. A transformation matrix and a plane equation of the CT scan are used to match points of the object space to the image space detecting fiducial markers on the CT scans by an automatic algorithm. For position measurements a special reference frame and surgical instruments were developed and equipped with infrared light-emitting diodes that could be detected in real time. Measurements for repositioning of the reference system in a model and during real operations demonstrated a mean error ranging from 0.69 to 1.01 mm and from 0.76 to 1.67 mm respectively. Clinical experience with the application of the system for 15 patients who underwent surgery for different paranasal sinus pathologies is reported.

CONCLUSIONS

Results suggest that the non-invasive reference system and the locatable surgical tools may be effective, accurate and useful for computer-assisted identification of intranasal structures. Such systems may contribute to further improvement of minimal invasive intranasal sinus surgery.

[Dizziness from a neuro-otological viewpoint]

The symptom of vertigo can be due to many different causes. Differential diagnosis will be discussed primarily from a neuro-otologic point of view. Vertigo can be thought of as a subjective disturbance of the integration of different sensory inputs. The history and subjective characterisation of vertigo often provide enough information for initial differential diagnosis and recommendation for a specific evaluation. The evaluation includes simple tests of posture and gait, tests of ocular motility, and examination of nystagmus. Instability and nystagmus towards a specific direction point to a vestibular disorder, especially if the nystagmus is suppressed by optical fixation. The most common causes of a vestibular disorder are benign paroxysmal positional vertigo (BPPV), a sudden vestibular loss (or vestibular neuritis), and Ménière's disease. These three diseases are discussed briefly.

[New aspects in surgery of the thyroid gland with intraoperative monitoring of the recurrent laryngeal nerve]

A method for electrophysiological monitoring of the recurrent laryngeal nerve during thyroid surgery is described. An electromyographic record from the muscles of the vocal folds is obtained using two fine needle electrodes. The electrodes are placed endoscopically. The nerve is identified by electrical stimulation, and the electromyographic activity is registered using a Nerve Integrity Monitor NIM-2 (Xomed-Treace). Our experience with this method in 43 patients is described. The safety of the integrity of the recurrent laryngeal nerve is increased using intraoperative monitoring. This has led to a modification of the operative concept in thyroid surgery. Electrophysiological monitoring is mandatory in surgery of large goitres, retrotracheal and substernal extension, for re-operations and malignant diseases of the thyroid gland.

Otoacoustic emissions: an approach for monitoring aminoglycoside-induced ototoxicity

Ototoxic drugs, such as aminoglycosides, affect outer hair cell integrity in the inner ear. Transiently evoked otoacoustic emission (TEOAE) characteristics are related to outer hair cell function and can be expected to reflect the influence of ototoxic agents. Transiently evoked otoacoustic emissions were measured during amikacin sulfate therapy in nine patients. The duration of treatment for individual patients ranged from 9 to 33 days. A reversible decrease of overall TEOAE level, occurring after a treatment period longer than 16 days, was found in the majority of patients. The monitoring of TEOAEs is proposed as a method for early identification and, as a result, prevention of aminoglycoside-induced ototoxicity.

Peripheral analysis of frequency in human ears revealed by tone burst evoked otoacoustic emissions

Otoacoustic emissions were evoked in the same ears with single tone bursts at 1, 2 and 3 kHz and with a complex stimulus consisting of a digital addition of the three tone bursts. Stimuli were presented at 75, 59 and 37 dB SPL to 28 ears of human subjects with normal hearing. The purpose was to determine if comparisons of responses to the complex stimulus with a posthoc addition of responses from single tone bursts could delineate features of cochlear frequency analysis of short-duration signals. For processing of the data, the results from the individual tone bursts were combined offline to form a composite response. This was then compared with the response obtained with the complex stimulus. Results revealed close correspondence between the spectra of the complex and composite responses in all ears despite interindividual differences in response morphology. Correlations between the complex and composite waveforms exceeded 80% for all stimulus levels. Subtractions of the two spectra revealed that the majority of the differences occurred at frequencies on the high-frequency slopes of the 1- and 2-kHz spectral peaks. This was due to a reduction in energy for the responses obtained with the complex stimulus. There was little variation between the two response types in the peak frequencies of their spectra, in the energy at frequencies on the lower frequency sides of the spectral peaks at 1 and 2 kHz, or in the spectral components at 3 kHz. Results reveal characteristics of the analysis of frequency in the preneural stages of cochlear processing.

Silicone stents in the management of inoperable tracheobronchial stenoses. Indications and limitations

BACKGROUND

Various stent models have been developed for the treatment of inoperable stenoses of the central airways caused by external compression. Increasing use is made of the silicone stents designed by Dumon. We tested their technical feasibility, tolerance, and long-term efficacy in relieving respiratory symptoms in patients referred for endoscopic palliation of malignant disease.

METHODS

All procedures were performed under general anesthesia with the use of the rigid bronchoscope. We inserted 38 stents in 31 patients (median age, 67 years; 25 men and 6 women) whose airways showed residual obstruction of > 50 percent of the lumen after laser resection of endobronchial tumor and/or mechanical dilatation of extrinsic compressions.

RESULTS

Stent placement and removal--where necessary--were easy in all patients, but five stents inserted in three patients with short (< or = 2.5 cm) and conical stenoses migrated, necessitating emergency removal. In 27 of the remaining 28 patients, stent tolerance was excellent; 1 proximal tracheal stent (< 1 cm below the vocal cords) had to be removed because of otalgia and dysphagia. One lethal hemoptysis occurred within hours after a repeated laser therapy and removal of an indwelling stent. No other serious complications occurred. Immediate and lasting relief of dyspnea and improvement in performance status (Karnofsky scale, activity index) was achieved in 90 percent (28/31) of patients (p < 0.01). The influence of adjuvant radiotherapy on local tumor recurrence and survival was analyzed in a subgroup of ten patients with stage IIIB squamous cell carcinoma with comparable performance status. Five did not undergo adjuvant radiotherapy (group A) and five did (group B). In group A, four of five stents were occluded by tumor recurrence above or below the stent after a median follow-up of 2 months; in group B, zero of five were occluded (p < 0.05) after 4 months. Median survival was 4 months in group A and 6 months in group B; the difference did not reach significance.

CONCLUSIONS

The silicone stents designed by Dumon are easily inserted and removed; they are also well tolerated and very efficacious in relieving respiratory symptoms caused by extrinsic airway compression. Short and conical stenoses present limitations for their use due to increased risk of migration. Combined treatment with laser resection, stent insertion, and subsequent radiotherapy is necessary to prevent local tumor recurrence and may improve survival.

[Sudden deafness]

Sensorineural hearing loss with rapid onset occurring without obvious reasons is considered a clinical entity called sudden hearing loss. Such hearing dysfunctions must be rated as severe handicaps, comparable to a sudden loss of vision. Neither the patient nor the physician should regard sudden deafness as a minor incident. An immediate and meticulous search for possible causes is mandatory. As a first step, an otoscopic examination should be carried out, and the hearing loss must be documented by an audiometric evaluation. Further steps of management will be tailored according to the results of these examinations. In some cases, immediate therapeutic measures must be taken to improve the patient's hearing loss. Therefore, an emergency referral of the patient to an otologist is to be recommended in all cases of sudden hearing loss.

Effects of atmospheric pressure variation on spontaneous, transiently evoked, and distortion product otoacoustic emissions in normal human ears

The effects of atmospheric pressure changes on the frequency and amplitude of spontaneous (SOAEs), transiently evoked (TEOAEs) and distortion product (DPOAEs) otoacoustic emissions in normally hearing humans were compared. The purpose was to determine if the transmission of each form of OAE was influenced differently by the middle ear. Sixty-one subjects were tested in a pressure chamber. Twenty-seven SOAEs with a frequency range between 535 to 4729 Hz from 21 subjects were examined. Transiently evoked OAEs were studied in 20 subjects using clicks and tone-bursts at 0.5, 1, 2, 3, and 4 kHz. Distortion-product OAEs were generated at seven geometric mean frequencies between 1 and 8 kHz in another 20 subjects. Spontaneous OAEs were examined by applying atmospheric pressure up to 9 kPa and down to -2.5 kPa, for the measurement of TEOAEs and DPOAEs the pressure was varied from 0 kPa up to 8 kPa. In spite of large interindividual differences, results suggest that the influence of pressure on the three OAEs is frequency specific. The frequency and amplitude change of SOAEs, the modification of the amplitude and spectra of TEOAEs, and the amplitude change of DPOAEs are more influenced by changes in middle ear pressure below 4 kHz than are OAEs in the range at 4 kHz and above.