Outcomes of Mastoidectomy With Antibiotic Catheter Irrigation for Patients With Draining Ventilation Tubes

OBJECTIVES

To evaluate the effectiveness of mastoidectomy with antibiotic catheter irrigation in patients with chronic tympanostomy tube otorrhea.

METHODS

A chart review of adult and pediatric patients with persistent tympanostomy tube otorrhea who had failed outpatient medical management and underwent mastoidectomy with placement of a temporary indwelling catheter for antibiotic instillation was performed. Patients were retrospectively followed for recurrent drainage after 2 months and outcomes were categorized as resolution (0-1 episodes of otorrhea or otitis media with effusion during follow-up), improvement (2-3 episodes), or continued episodic (>3 episodes).

RESULTS

There were 22 patients and 23 operated ears. Median age was 46 years (interquartile range, IQR = 29-65). The median duration of otorrhea from referral was 5.5 months (IQR = 2.8-12). Following surgery, 14 ears had resolution of drainage, 6 had improvement, and 3 had episodic. The observed percentage of resolved/improved ears (87%) was significant (P = .0005, 95% CI = 67.9%-95.5%). Median follow-up time was 25 months (IQR = 12-59). Pre and postoperative pure tone averages improved (difference of medians = -3.3 dB, P = .02) with no significant difference in word recognition scores (P = .68). Methicillin-resistant Staphylococcus aureus was the most common isolated microbe while no growth was most frequently noted on intraoperative cultures.

CONCLUSIONS

Mastoidectomy with antibiotic catheter irrigation may be an effective surgical strategy, and single stage alternative to intravenous antibiotics, for select patients with persistent tube otorrhea who have failed topical and oral antibiotics.

A Deep Learning Model for Automated Classification of Intraoperative Continuous EMG

Objective

Intraoperative neurophysiological monitoring (IONM) is the use of electrophysiological methods during certain high-risk surgeries to assess the functional integrity of nerves in real time and alert the surgeon to prevent damage. However, the efficiency of IONM in current practice is limited by latency of verbal communications, inter-rater variability, and the subjective manner in which electrophysiological signals are described.

Methods

In an attempt to address these shortcomings, we investigate automated classification of free-running electromyogram (EMG) waveforms during IONM. We propose a hybrid model with a convolutional neural network (CNN) component and a long short-term memory (LSTM) component to better capture complicated EMG patterns under conditions of both electrical noise and movement artifacts. Moreover, a preprocessing pipeline based on data normalization is used to handle classification of data from multiple subjects. To investigate model robustness, we also analyze models under different methods for processing of artifacts.

Results

Compared with several benchmark modeling methods, CNN-LSTM performs best in classification, achieving accuracy of 89.54% and sensitivity of 94.23% in cross-patient evaluation.

Conclusion

The CNN-LSTM model shows promise for automated classification of continuous EMG in IONM.

Significance

This technique has potential to improve surgical safety by reducing cognitive load and inter-rater variability.

The Role of Mastoidectomy in Draining Ventilation Tubes

OBJECTIVES

To discuss the indication for performing a mastoidectomy with catheter placement in patients with chronic tympanostomy tube otorrhea.

METHODS

The Medical Literature Analysis and Retrieval System Online was searched via PubMed for relevant articles using serous mastoiditis, mastoidectomy, chronic otorrhea, tube otorrhea, tympanostomy tubes, and biofilm as keywords.

RESULTS

Further understanding of the pathophysiology of otorrhea and the development of ototopical fluoroquinolones have made a draining tympanostomy tube more manageable. Nevertheless, chronic otorrhea refractory to an otolaryngologist's traditional treatment algorithm still occurs and may benefit from a mastoidectomy with antibiotic irrigation using a catheter in certain cases. We theorize that resolution of otorrhea results from this technique by decreasing the burden of diseased mucosa and providing a larger concentration or dose of antibiotic to the middle ear cleft through the antrum. High-resolution images of the technique and catheter placement are included in this review.

CONCLUSIONS

Despite being an uncommon management strategy, the literature suggests an indication for performing a mastoidectomy in a small percentage of patients with a chronically draining tympanostomy tube.

Long-term outcomes of cartilage-buttressed T-tube tympanoplasty for prolonged middle ear ventilation

OBJECTIVES/HYPOTHESIS

To report on the safety and efficacy of cartilage-buttressed T-tube tympanoplasty for long-term middle ear ventilation, specifically by examining duration of tube survival, as well as adverse events associated with prolonged middle ear intubation, including persistent tympanic membrane perforation.

STUDY DESIGN

Retrospective case series of patients undergoing cartilage-buttressed T-tube tympanoplasty between January 2005 and December 2016 in a tertiary-care neurotology private practice.

METHODS

Patients who underwent cartilage T-tube tympanoplasty with complete pre- and postoperative audiometric data and a minimum follow-up duration of 12 months were analyzed. T-tube survival and adverse events including persistent tympanic membrane perforation were recorded and compared to published data for other long-term middle ear ventilation techniques.

RESULTS

The study cohort included 72 cartilage-buttressed T-tube tympanoplasties in 68 patients. Median tube survival was 34 months (range, 2-131 months). Incidence of persistent tympanic membrane perforation (n = 1) was 1.4% CONCLUSIONS: Cartilage-buttressed T-tube tympanoplasty is a safe and effective means of accomplishing long-term middle ear ventilation with a considerably lower rate of persistent tympanic membrane perforation as compared to alternative methods of prolonged middle ear ventilation.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:203-208, 2019.

The Comparative Risks of Bacterial Contamination between a Venturi Atomizer and a Positive Displacement Atomizer

Introduction

This laboratory study determined the incidence of internal contamination of Venturi principle atomizers and positive displacement atomizers exposed to high external concentrations of Staphylococcal aureus (Staph).

Methods

Atomizer device nozzle tips were immersed into a Staph solution and 1 ml of spray was atomized via compressed wall air (Venturi) or hydraulic pump (positive displacement). The Venturi nozzle was then wiped with 70% isopropyl alcohol while the disposable positive displacement nozzle was replaced. After 30 minutes, 1 ml of atomized fluid was collected and cultured and the process was repeated. After sixteen uses the fluid remaining in the bottles was cultured. The Venturi atomizer also was subjected to a single use trial to determine the location of device contamination.

Results

Venturi atomizers sprays grew Staph in every case (144/144), while positive displacement atomizer sprays never grew contaminants (0/144; p < 0.0001). At the end of 16 uses, 7/9 of Venturi atomizers had Staph within their medication reservoirs while none (0/9; p = 0.002) existed in the positive displacement atomizers. After a single use of the Venturi atomizer, the medication reservoir, the air lumen and the medication lumen of the nozzle were all contaminated with Staph.

Conclusions

External bacterial contamination of the atomizer nozzle tip results in internal bacterial contamination of Venturi devices in as little as one use but not of positive displacement devices. These results warrant further investigation to determine whether a risk of cross-contamination exists in a clinical setting.

Hydroxyapatite cement cranioplasty following translabyrinthine approach: Long-term study of 369 cases

OBJECTIVE

To report the authors' experience with hydroxyapatite cement (HAC) cranioplasty and analyze the material's long-term safety and efficacy in repairing translabyrinthine skull-base defects by examining adverse events, specifically cerebrospinal fluid (CSF) leaks and surgical site infections.

STUDY DESIGN

Retrospective case-control study (primary study arm); prospective cross-sectional study of patients not examined within the last 5 years (secondary arm).

SETTING

tertiary-care neurotology private practice and academic practice (two centers).

METHODS

Hydroxyapatite cement implanted following translabyrinthine approach, with or without fat graft, was included. Combined approaches were excluded. Implant-associated adverse events were defined as 1) CSF leaks requiring reoperation or spinal drainage, and (2) infections requiring reoperation. Patients not examined within 5 years were interviewed by telephone to update their condition. Incidence of adverse events was compared to published data for translabyrinthine cranioplasty using fat graft alone. Implant survival analysis was performed.

RESULTS

The study cohort included 369 HAC implants in the same number of patients. There were seven CSF leaks and seven infections. Combined (n = 14) incidence of adverse events was 3.8% (2.09%, 6.28%). Compared to fat graft alone, the adverse events associated with HAC were fewer (P < 0.001). Up to 15 years (5,475 days), HAC cement maintained 95% adverse event-free survival. There were no cases of meningitis.

CONCLUSION

Cranioplasty using HAC with autologous fat following translabyrinthine skull-base surgery is safer and more effective than fat graft alone, up to 15 years after surgery.

LEVEL OF EVIDENCE

4. Laryngoscope, 127:2120-2125, 2017.

Fungal skull base osteomyelitis: Emerging microbial identification techniques

Culture-based pathogen identification in skull base osteomyelitis, particularly for fungi, is often inaccurate. We report the case of patient with fungal skull base osteomyelitis cured by sustained antifungal therapy after 16 months of debilitating illness. Due to medical complications, a strong clinical rationale was needed to justify long-term antifungal therapy. The offending fungus was identified by experimental molecular technology (Ibis T5000 universal biosensor); invasive fungal disease was corroborated by biochemical assays. Our discussion will help familiarize the otolaryngologist with existing biochemical and molecular diagnostics for invasive fungal disease. We encourage future investigators to study their application in cases of skull base osteomyelitis. Laryngoscope, 127:E5-E7, 2017.

Stapedectomy in Congenital Stapes Fixation: Are Hearing Outcomes Poorer?

OBJECTIVE: To evaluate outcomes of stapedectomy surgery for congenital stapes fixation.

STUDY DESIGN: Retrospective chart review.

METHODS: The charts of 463 stapedectomies performed by 1 surgeon from 1996 to 2003 were reviewed. Patients with a history of childhood hearing loss and operative findings consistent with congenital fixation of the stapes were included. Patients with a history of trauma or chronic otitis media and those with otosclerosis were excluded. Thirty-six patients underwent stapedectomy for congenital fixation. Revision cases and those with inadequate postoperative bone or air conduction data were excluded. Inclusion criteria were met for 25 patients. Operative findings and hearing outcomes were evaluated.

RESULTS: The study group was comprised of 25 stapedectomies. Closure of the air-bone gap to less than 10 dB was achieved in 48% of cases, and 80% had closure within 20 dB. A gap of more than 30 dB remained in 3 cases. There were 2 cases of sensorineural hearing loss with worsening of the bone conduction thresholds by 15 dB and 30 dB. There were no instances of perilymph gusher. In addition to an excluded case that was not reconstructed because of facial nerve position, 3 of the included patients were found to have a dehiscent facial nerve at surgery. There were no facial nerve injuries, and fixation of the malleus or incus was not found in any of the included patients. When hearing outcomes were compared with our results for otosclerosis over the same time period, rates of closure to within 10 dB and 20 dB were significantly worse in the congenital group.

CONCLUSION: Closure of the air-bone gap in this population differs from our results in stapedectomy done for otosclerosis. This difference likely reflects subtle anatomic variations in the congenital group that affect the effectiveness of the prosthesis. Despite the difference in results, stapedectomy for congenital fixation remains an effective method to achieve significant hearing improvement in the majority of patients.

EBM rating: B-3b

Differences in genotype and virulence among four multidrug-resistant Streptococcus pneumoniae isolates belonging to the PMEN1 clone

We report on the comparative genomics and characterization of the virulence phenotypes of four S. pneumoniae strains that belong to the multidrug resistant clone PMEN1 (Spain^23F ST81). Strains SV35-T23 and SV36-T3 were recovered in 1996 from the nasopharynx of patients at an AIDS hospice in New York. Strain SV36-T3 expressed capsule type 3 which is unusual for this clone and represents the product of an in vivo capsular switch event. A third PMEN1 isolate – PN4595-T23 – was recovered in 1996 from the nasopharynx of a child attending day care in Portugal, and a fourth strain – ATCC700669 – was originally isolated from a patient with pneumococcal disease in Spain in 1984. We compared the genomes among four PMEN1 strains and 47 previously sequenced pneumococcal isolates for gene possession differences and allelic variations within core genes. In contrast to the 47 strains – representing a variety of clonal types – the four PMEN1 strains grouped closely together, demonstrating high genomic conservation within this lineage relative to the rest of the species. In the four PMEN1 strains allelic and gene possession differences were clustered into 18 genomic regions including the capsule, the blp bacteriocins, erythromycin resistance, the MM1-2008 prophage and multiple cell wall anchored proteins. In spite of their genomic similarity, the high resolution chinchilla model was able to detect variations in virulence properties of the PMEN1 strains highlighting how small genic or allelic variation can lead to significant changes in pathogenicity and making this set of strains ideal for the identification of novel virulence determinants.

Ossicular chain reconstruction: Titanium versus plastipore

OBJECTIVE

To compare the complication rate and hearing results of a new, lightweight, titanium ossicular replacement prosthesis with Plastipore prostheses (Xomed, Jacksonville, FL).

STUDY DESIGN

Retrospective.

METHODS

Charts were reviewed for type of operation, type of prosthesis used, extrusion rate, prostheses failure rate, and hearing thresholds at multiple frequencies and at multiple follow-up points. The dependant variable for hearing results was the four-frequency average air-bone gap.

RESULTS

There were 84 patients undergoing tympanoplasty with the Plastipore prosthesis and 53 with the titanium. There was one extrusion in the titanium group. There was an additional single incidence of prosthesis failure in the titanium group. Overall hearing results were comparable with an air-bone gap average of 19.3 dB in the Plastipore group compared with the titanium group with an air-bone gap of 22.0 dB (P =.08). Sixty percent of patients had a postoperative air-bone gap of 20 dB or less in the Plastipore group. In the titanium group, 45.3% achieved a 20 dB or less postoperative air-bone gap. Plastipore had a lower air-bone gap than the titanium when a canal wall up operation was performed (17.8 vs. 23.9 dB) and tended toward a lower air-bone gap when a total ossicular prosthesis was needed (22 vs. 27 dB) (P <.07).

CONCLUSION

The titanium prosthesis is a new ossicular replacement prosthesis that provides excellent visualization during insertion and provides hearing results that are comparable with Plastipore. The Plastipore prosthesis performed better in canal wall up mastoidectomy situations and tended toward better performance when a total ossicular replacement prosthesis was needed.

Acoustic tumor observation and failure to follow-up

OBJECTIVE

To review the clinical course of patients undergoing observation for their acoustic tumor with evaluation of the incidence and contributing variables to failure to follow-up.

STUDY DESIGN

Case series with chart review and telephone interview.

SETTING

Single subspecialty practice.

SUBJECTS AND METHODS

One hundred twenty-two patients underwent an observation period after their unilateral acoustic tumor was diagnosed. Follow-up patterns were noted and multiple patient variables were analyzed to determine risk factors that contributed to risk of failing to keep prescribed follow-up. Telephone interviews and/or public record reviews were conducted to determine the reasons for failing to follow-up.

RESULTS

Fifty-two (42.6%) patients failed to keep prescribed follow-up. No preoperative patient or tumor variables were correlated with the risk of failure to follow-up. The investigators were able to contact and interview 20 patients to determine reasons for not keeping follow-up. Of these patients, nine (45%) electively chose not to follow-up, six (30%) did not appear to have a clear understanding of their diagnosis or treatment options despite adequate counseling, and five (25%) had medical problems that took precedence over the acoustic tumor. Very few patients elected to reschedule follow-up even after contact was made.

CONCLUSION

Failure to follow-up is a serious problem with acoustic tumor observation protocols. It is difficult to detect which patients are at risk for noncompliance. Patient noncompliance with observation protocols should be considered when determining the most appropriate treatment for each acoustic tumor patient.

An alternative treatment for facial nerve tumors: short-term results of radiotherapy

A review of medical records of patients undergoing radiotherapy for facial nerve tumors was undertaken to determine subsequent facial nerve results, hearing results, and tumor control. Two patients with facial nerve tumors received this treatment. Facial nerve function remains excellent in one patient and significantly improved in the other. Neither tumor demonstrated growth. Current philosophies of facial nerve schwannoma management attempt to balance tumor control with facial nerve function. Radiotherapy for these tumors appears to preserve short-term facial function and may be a viable alternative to surgical management.

Antibody reactivity to heat shock protein 70 and inner ear-specific proteins in patients with idiopathic sensorineural hearing loss

Deafness is attributable to autoimmunity in a subset of adult patients with sensorineural hearing loss (SNHL) of unknown aetiology. To determine the roles of self-antigens in the pathogenesis of idiopathic SNHL, we analysed antibody responses to the inner ear-specific proteins, cochlin and beta-tectorin as well as the non-specific heat shock protein 70 (HSP70). Recombinant cochlin and beta-tectorin proteins were used in a qualitative Western blot assay for the detection of antigen-specific IgG antibodies in 58 patients with idiopathic SNHL and 28 healthy blood donors. In the same study cohort, we also used a Western blot assay to assess IgG antibody responses to the recombinant human HSP70. Of the 58 patient samples analysed, 19 tested positive to the HSP70, eight to cochlin and one to beta-tectorin, giving a prevalence of 33, 14 and 2%, respectively. Only one patient sample was reactive for HSP70, cochlin and beta-tectorin, seven of the remaining eight cochlin IgG antibody-positive samples were monospecific. Thus, cochlin-specific antibodies were observed predominantly in HSP70 IgG-negative patients demonstrating an additive value for testing this antibody response in patients with idiopathic SNHL.

Combined Petrosal Approaches in the Management of Temporal Bone Meningiomas

OBJECTIVES

To evaluate the indications and outcomes of the combined petrosal approaches in the surgical management of temporal bone meningiomas.

STUDY DESIGN

Retrospective chart review.

SETTING

University teaching hospital.

PATIENTS

Adults with temporal bone meningiomas.

INTERVENTION(S)

Meningioma removal using a combined petrosal approach.

MAIN OUTCOME MEASURE(S)

Cranial nerve outcomes, complications, completeness of resection, and recurrence rates.

RESULTS

Forty-nine patients underwent surgical excision of a temporal bone meningioma between 1996 and 2004 at our institution. Nineteen of these patients required a combined petrosal approach for excision. The most common presenting complaints were balance disturbance, 11 (58%); hearing loss, 10 (53%); headache, 10 (53%); and tinnitus, 9 (47%). The most common tumor origin was of the petrous ridge (14; 74%). Average tumor size was 3.1 cm. Complete resection was possible in 17 (89%) patients. Upper cranial nerve (III-VI) function was improved in two (11%) patients and worsened in three (16%) patients. Lower cranial nerve (IX-XII) function improved in one (5%) patient and was worsened in one (5%) patient. Postoperative facial nerve function was Grades I to II in 16 (84%) patients and Grades III to IV in 1 (5%) patient at last follow-up. Hearing data were available in 14 patients. Of those patients, 11 (85%) had serviceable hearing after surgery. The most common surgical complication was a cerebrospinal fluid leak, with three (16%) incidences. There were no reported incidents of stroke, death, or meningitis in the cohort.

CONCLUSION

The use of the combined petrosal approach for temporal bone meningioma resection results in favorable outcomes for the patient. The incidence of complications is acceptably low, and cure rates are high.

Visually Enhanced Vestibulo-Ocular Reflex: A Diagnostic Tool for Migraine Vestibulopathy

OBJECTIVES

1) To compare the incidence of elevated visually enhanced vestibular-ocular reflex (VVOR) rotational gain during rotational chair testing in a normal control group versus a group of patients diagnosed with migraine vestibulopathy; 2) to discuss the possible application of VVOR gain during rotational chair testing for diagnosing migraine vestibulopathy.

STUDY DESIGN

Prospective normal control group and retrospective cohort comparison.

METHODS

1) Prospective rotational chair studies including VVOR in 20 normal control patients; 2) retrospective review of vestibular studies including VVOR in 100 consecutive patients with migraine vestibulopathy.

RESULTS

Twenty of the normal controls and 69 of the migraine vestibulopathy patients met all inclusion criteria. One of 20 (5%) normal control patients had elevated VVOR gain, whereas 49 of 69 (71%) of migraine vestibulopathy patients had elevated VVOR gain.

CONCLUSIONS

VVOR gain normal criteria were appropriate in 95% of our normal control test group. VVOR gain was more frequently elevated in migraine vestibulopathy patients than in the normal controls, and the difference was significant (P < .001). VVOR gain elevation was the most common vestibular test abnormality in this cohort of patients with migraine vestibulopathy. Because VVOR measures visual-vestibular interaction and its central connections, this parameter may be a useful diagnostic tool for migraine vestibulopathy in patients manifesting disequilibrium and motion sensitivity.

Reversible Peripheral Vestibulopathy: The Treatment of Superior Canal Dehiscence

OBJECTIVE

Superior canal dehiscence (SCD) is a recently described disorder that results from absence of bone over the superior semicircular canal. We have reviewed 30 cases of SCD found at our institution and report their presentation, workup, and response to therapy.

STUDY DESIGN

Retrospective chart review of all patients diagnosed with SCD from 1999 to 2004 at the University of Utah.

RESULTS

Thirty patients were identified with SCD. Patients presented with chronic disequilibrium (63%), Tullio's phenomenon (41%), pressure evoked vertigo (44%), hearing loss (30%), and pulsatile tinnitus (7%). ENG performed early in our series revealed abnormal nystagmus with sound presentation, Valsalva, or tympanogram; however, history and CT examination alone was used to identify this condition in most of our patients. Twenty-seven of the 30 patients had some symptoms related to SCD; the other 3 were found to have incidental SCD on CT examination. Of these patients, 14 had severe enough symptoms to warrant operative intervention. All, but one had resolution of their symptoms after completion of intervention.

CONCLUSIONS

Superior canal dehiscence is a highly treatable form of vestibulopathy once recognized. When patients present with typical symptoms, workup with CT is reliable and accurate. Surgical intervention results in reversal of symptoms in most cases with low morbidity.

EBM RATING

C-4.

Implantation of the ossified cochlea: management with the split electrode array

OBJECTIVES/HYPOTHESIS

To describe indications for, the surgical technique required, and the expected functional results of split electrode array cochlear implants.

STUDY DESIGN

Retrospective chart review.

METHODS

Data collected included etiology of deafness, radiographic findings, pre- and postoperative aided pure tone thresholds, and speech perception testing. Adult speech perception outcomes were measured using the Consonant Nucleus Consonant (CNC) monosyllable words and Hearing in Noise Test (HINT) in quiet/noise (+10 dB). The children were assessed using the Infants and Toddlers Meaningful Auditory Integration Scale.

RESULTS

Five patients were implanted with a split electrode array. This included two adults and three children. Both adults had preoperative binaural aided pure tone averages worse than 50 dB and scores of 0% on both HINT quiet and CNC words. The children had undetectable preoperative aided thresholds and scored an average 4/40 on the IT-MAIS. Postimplant, the average threshold gain was 38.5 dB in the adults and 81.5 dB in the children. One adult improved to score 51%/22% on HINT quiet/noise at 6 months and 72%/30% at 12 months. The other adult continued to score 0% on HINT at 12 months but claimed substantial subjective auditory improvement after the first year of device use. The children averaged 28/40 on the IT MAIS at 6 months after implantation. Forty-two of 48 implanted electrodes were functional.

CONCLUSIONS

The split electrode array is a useful alternative to traditional cochlear implants in treating deafened patients with cochlear ossification. Patients implanted with the split array show marked improvement in sound and speech perception.

Jugular Foramen Schwannomas: Diagnosis, Management, and Outcomes

OBJECTIVES/HYPOTHESIS

To describe the presentation, radiographic findings, and surgical management of seven patients who have been diagnosed and treated with jugular foramen schwannomas at the University of Utah.

STUDY DESIGN

Retrospective chart review.

METHODS

The charts of seven patients diagnosed with jugular foramen schwannomas were reviewed for presentation symptoms, radiographic findings, and physical examination findings. For the six who underwent surgical excision, the surgical procedure used, cranial nerve function results, audiometric results, perioperative complications, and other follow-up data are presented.

RESULTS

Seven patients were identified from ages 24 to 69 years. Six of the seven underwent surgical excision. Primary presentation symptoms included dizziness, hearing loss, dysphagia, diplopia, tongue paresis, and hoarseness. The choice of surgical approach was based on the size and location of the tumor. All patients had complete excision of their tumors. The nerve of origin included the glossopharyngeal, vagus, and spinal accessory nerves. Preoperative cranial nerve dysfunction continued postoperatively for lower cranial nerves but resolved in patients who were noted to have preoperative dysfunction of cranial nerve V and VI. The rate of new lower cranial nerve injury was 15% and was only seen in the cranial nerves that were determined to be the nerve of origin. In two cases, a temporary feeding tube was required. No recurrences have been noted to date.

CONCLUSIONS

Jugular foramen schwannomas can be successfully diagnosed preoperatively with computed tomography and magnetic resonance imaging. These tumors can be successfully managed with surgery and low morbidity.

Vestibular nerve section versus intratympanic gentamicin for Meniere's disease

OBJECTIVES/HYPOTHESIS

Vestibular nerve section and transtympanic gentamicin administration are procedures with proven efficacy in the treatment of vertigo associated with Meniere's disease refractory to medical management. Hearing loss is a known complication of each of these procedures; however, there has not been a report of hearing results of both treatments from a single institution.

STUDY DESIGN

Retrospective review.

METHODS

Review was made of 25 patients undergoing gentamicin injection and 39 patients undergoing vestibular nerve section for Meniere's disease. Rate of vertigo control and pretreatment and post-treatment pure-tone average values and speech discrimination scores were reported.

RESULTS

The mean preoperative pure-tone average for patients having vestibular nerve section was 47.2 dB, with a speech discrimination score of 75.4%. In these patients, the postoperative pure-tone average was 49.1 dB and the speech discrimination score was 75%. Patients undergoing gentamicin injection had a mean pretreatment pure-tone average of 55.9 dB and a speech discrimination score of 62%. The post-treatment pure-tone average and speech discrimination score for the gentamicin group were 68.8 dB and 49.3%, respectively. Five of 25 patients (20%) in the gentamicin treatment group and 1 of 39 (3%) in the vestibular nerve section treatment group had an increase in bone-conduction threshold greater than 30 dB. The amount of postprocedure hearing loss was significantly greater in the gentamicin treatment group (P =.006). Control of vertigo was good to excellent in 95% of the patients treated with vestibular nerve section and in 80% of the patients treated with gentamicin.

CONCLUSION

Although vestibular nerve section and transtympanic gentamicin are both acceptable treatment options for vertigo associated with Meniere's disease, gentamicin causes a higher level of hearing loss related to treatment and vestibular nerve section has higher vertigo control rates.

The comparative risks of bacterial contamination between a venturi atomizer and a positive displacement atomizer

INTRODUCTION

This laboratory study determined the incidence of internal contamination of Venturi principle atomizers and positive displacement atomizers exposed to high external concentrations of Staphylococcal aureus (Staph).

METHODS

Atomizer device nozzle tips were immersed into a Staph solution and I ml of spray was atomized via compressed wall air (Venturi) or hydraulic pump (positive displacement). The Venturi nozzle was then wiped with 70% isopropyl alcohol while the disposable positive displacement nozzle was replaced. After 30 minutes, 1 ml of atomized fluid was collected and cultured and the process was repeated. After sixteen uses the fluid remaining in the bottles was cultured. The Venturi atomizer also was subjected to a single use trial to determine the location of device contamination.

RESULTS

Venturi atomizers sprays grew Staph in every case (144/144), while positive displacement atomizer sprays never grew contaminants (0/144; p < 0.0001). At the end of 16 uses, 7/9 of Venturi atomizers had Staph within their medication reservoirs while none (0/9; p = 0.002) existed in the positive displacement atomizers. After a single use of the Venturi atomizer, the medication reservoir, the air lumen and the medication lumen of the nozzle were all contaminated with Staph.

CONCLUSIONS

External bacterial contamination of the atomizer nozzle tip results in internal bacterial contamination of Venturi devices in as little as one use but not of positive displacement devices. These results warrant further investigation to determine whether a risk of cross-contamination exists in a clinical setting.