Microbiome and Otic Quinolone Levels Following Tympanoplasty Assessed by Gelatin Sponge Analysis

OBJECTIVE

To determine if absorbable gelatin sponge (AGS) can be used to assess the posttympanoplasty microbiome and otic antibiotic exposure.

STUDY DESIGN

Prospective.

SETTING

Tertiary hospital.

METHODS

Patients undergoing tympanoplasty were prospectively enrolled. Intraoperatively, AGS was applied to the medial ear canal/tympanic membrane (TM) for 1 minute after canal incision, then saved for analysis. Ear canals were packed with AGS at the end of surgery. Otic ofloxacin was administered until the first postoperative visit, when AGS was collected. Microbial presence was assessed by culture. Ofloxacin levels were assessed by liquid-chromatography mass-spectrometry.

RESULTS

Fifty-three patients were included. AGS was collected in 92.9% of patients seen within 21 days compared to 70.8% of those seen at 22 to 35 days. At surgery, AGS yielded bacteria and fungi in 81% and 11%, respectively, including Staphylococcus species (55%) and Pseudomonas species (25%). Postoperatively, AGS yielded bacteria in 71% and fungi in 21% at the meatus, (staphylococci 57% and pseudomonas 25%). TM samples yielded bacteria in 69%, fungi in 6%, staphylococci in 53%, and pseudomonas in 19%. Ofloxacin concentration at the meatus was 248 μg/mL (95% confidence interval [CI]: 119-377) and at the TM was 126 μg/mL (95% CI: 58-194). Ofloxacin-resistant colonies were found in 75% of patients.

CONCLUSION

Analysis of AGS is a viable technique for noninvasively studying healing metrics posttympanoplasty, including the microbiome and otic antibiotic exposure. Despite exposure to a high concentration of quinolones, the tympanoplasty wound is far from sterile, which may impact healing outcomes.

Potential Toxicity of Boric Acid Powder Otic Insufflation

OBJECTIVE

Boric acid (BA) powder is commonly used to treat otologic conditions, such as mastoid bowl inflammation and chronic otitis externa. Exposure to 50 mg per day is thought to cause systemic toxicity in humans. Inflamed skin and mucosal surfaces readily absorb BA. The aim of this study was to measure the doses of BA commonly used in clinical otology and alert the otolaryngology community to BA's underappreciated potential source of systemic toxicity.

STUDY DESIGN

Prospective, controlled.

SETTING

Laboratory.

METHODS

BA dose administration was measured by weighing the BA generated by common insufflators: accordion bellows, House-Sheehy insufflator, DeVilbiss insufflator, and pneumatic powder blower. Manual insufflation was performed with 3 compressions of the bulb. The pneumatic blower was sprayed for 1 second. Measurements were repeated 10 times.

RESULTS

The DeVilbiss insufflator delivered the lowest mean BA dose, 6.1 mg (SD 3.4, range 2.1-13.7), followed by the House-Sheehy 8.9 mg (SD 8.4, range 1.6-27.8), the pneumatic blower 192.8 mg (SD 38.3, range 150.0-261.7), and the accordion, 284.1 mg (SD 215.0, range 37.8-730.8).

CONCLUSION

BA dose delivery is highly variable by insufflator type, and doses thought to cause systemic toxicity are commonly generated. Awareness of and further investigation into the potential toxicity of otic administration of BA seems warranted.

Tympanoplasty Healing Outcomes With Use of Postoperative Otic Quinolones

OBJECTIVE

Tympanoplasty usually results in tympanic membrane perforation (TMP) closure, but healing may be suboptimal (e.g., excess scarring). Factors that have been linked to impaired TM healing have become widely adopted (especially, postoperative use of quinolone ear drops). The aim of this study is to assess the frequency of suboptimal tympanoplasty healing with the use of otic quinolones postoperatively.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary care facility.

PATIENTS

One hundred patients undergoing tympanoplasty for TMP.

INTERVENTIONS

Tympanoplasty +/- canalplasty.

MAIN OUTCOME MEASURES

Healing complications (e.g., granulation tissue, TMP, myringitis, bone exposure, lateralization, anterior blunting, medial canal fibrosis, and canal stenosis) and hearing loss.

METHODS

Charts were reviewed for postoperative healing issues and hearing outcomes at 1 to 2 years postoperatively.

RESULTS

TMP closure was found in 93.2%, but 34.2% had healing issues at 1 to 2 years postoperatively, with 20.6% having adverse healing outcomes (perforation (6.9%), granulation tissue (6.9%), medial fibrosis (4.1%), and myringitis, bone exposure, and webbing (all 1.4%). Another 13.7% had notable postoperative issues, such as protracted otorrhea (11.0%), otitis externa (9.6%), otitis media (1.4%), and atelectasis (2.7%). No medical, surgical, or patient factors impacted outcomes. Average air-bone gap at 1 to 2 years did not differ between patients with and without healing issues and patients with other postoperative issues (p = 0.5).

CONCLUSIONS

Suboptimal healing is common after tympanoplasty. There may be significant opportunity to improve post-tympanoplasty healing beyond improving the TMP closure rate.

Cytotoxicity of Tetracyclines in Human Tympanic Membrane Fibroblasts

HYPOTHESIS

Tetracyclines are less cytotoxic to tympanic membrane (TM) fibroblasts than quinolones.

BACKGROUND

Use of quinolone ear drops after tympanostomy tube placement and for acute otitis externa has been linked to an increased risk of TM perforation. This has been verified in animal models. Cell culture studies have shown quinolones to be highly toxic to TM fibroblasts. Tetracyclines are a potential alternative to quinolones as they have been used to treat acute otitis externa and are thought to be nontoxic to the inner ear. We aimed to determine if tetracyclines are cytotoxic to TM fibroblasts.

METHODS

Human TM fibroblasts were treated with 1:10 dilutions of ofloxacin 0.3%, ciprofloxacin 0.3%, doxycycline 0.3 and 0.5%, minocycline 0.3 and 0.5%, tetracycline 0.3 and 0.5%, or dilute HCl (control), twice within 24 hours or four times within 48 hours. After 2 hours of treatment, cells were returned to growth media. Cells were observed with phase-contrast microscopy until cytotoxicity was measured.

RESULTS

Fibroblasts had lower survival with ciprofloxacin 0.3% and doxycycline 0.5% treatment compared with the control after 24 and 48 hours (all p < 0.0001). Fibroblasts treated with minocycline 0.5% had increased cell survival after 24 hours. Minocycline 0.3 and 0.5% showed increased TM fibroblast survival after 48 hours (all p < 0.0001). Phase-contrast images mirrored the cytotoxicity findings.

CONCLUSIONS

Tetracyclines are less toxic to cultured TM fibroblasts than ciprofloxacin. Fibroblast tetracycline toxicity is drug and dose specific. Minocycline shows the most promise for possible otic applications in which fibroblast toxicity is a concern.

Quinolone Ear Drops and Achilles Tendon Rupture

BACKGROUND

Delayed eardrum healing has been observed in the ear opposite to the ear treated with otic quinolones (OQ) in rats. Case reports describe tendinopathies after OQ treatment, suggesting adverse systemic effects.

METHODS

We studied patients aged 19 to 64 years with diagnosis of otitis externa or media in private insurance between 2005 and 2015. We compared OQ treatment against otic neomycin, oral amoxicillin, or azithromycin. Outcomes included Achilles tendon rupture (ATR), Achilles tendinitis (AT), and all-type tendon rupture (ATTR). We applied an active comparator, new-user design with 1-year look-back and ceased follow-up at initiation of systemic steroids or oral quinolones, external injury, hospitalization, and after 35 days. We used trimmed stabilized inverse probability of treatment weights to balance comparison groups in a survival framework. Negative outcomes (clavicle fractures or sports injuries) were examined to rule out differences from varied physical activity (unmeasured confounding).

RESULTS

We examined 1 501 009 treated otitis episodes. Hazard ratios (HR) for OQ exposure associated with ATR were 4.49 (95% confidence interval [CI], 1.83-11.02), AT 1.04 (95% CI, 0.73-1.50), and ATTR 1.71 (95% CI, 1.21-2.41). Weighted risk differences (RD) per 100 000 episodes for OQ exposure were ATR 7.80 (95% CI, 0.72-14.89), AT 1.01 (95% CI, -12.80 to 14.81), and ATTR 18.57 (95% CI, 3.60-33.53). Corresponding HRs for clavicle fractures and sports injuries were HR,1.71 (95% CI, 0.55-5.27) and HR,1.45 (95% CI, 0.64-3.30), suggesting limited residual confounding.

CONCLUSIONS

OQ exposure may lead to systemic consequences. Clinicians should consider this potential risk and counsel patients accordingly. Risk factors and mechanisms for this rare, adverse effect deserve further evaluation. Mechanistic and other clinical studies are warranted to corroborate this finding.

Watchful Waiting for Acute Otitis Media

BACKGROUND AND OBJECTIVES

Updated guidelines continue to support watchful waiting as an option for uncomplicated acute otitis media (AOM) and provide explicit diagnostic criteria. To determine treatment prevalence and associated determinants of watchful waiting for AOM in commercially insured pediatric patients.

METHODS

This was a retrospective cohort study using IBM Marketscan Commercial Claims Databases (2005 to 2019) of patients 1 to 12 years old with AOM, without otitis-related complications within 6 months prior, with no tympanostomy tubes, and no other infections around index diagnosis of AOM. We examined monthly antibiotic treatment prevalence (defined as pharmacy dispensing within 3 days of AOM diagnosis) and used multivariable logistic regression models to examine determinants of watchful waiting.

RESULTS

Among 2 176 617 AOM episodes, 77.8% were treated within 3 days. Whereas some clinical characteristics were moderate determinants for watchful waiting, clinician antibiotic prescribing volume and specialty were strong determinants. Low-volume antibiotic prescribers (≥80% of AOM episodes managed with watchful waiting) had 11.61 (95% confidence interval 10.66-12.64) higher odds of using watchful waiting for the index AOM episode than high-volume antibiotic prescribers (≥80% treated). Otolaryngologists were more likely to adopt watchful waiting (odds ratio 5.45, 95% CI 5.21-5.70) than pediatricians, whereas other specialties deferred more commonly to antibiotics.

CONCLUSIONS

Adoption of watchful waiting for management of uncomplicated, nonrecurrent AOM was limited and stagnant across the study period and driven by clinician rather than patient factors. Future work should assess motivators for prescribing and evaluate patient outcomes among clinicians who generally prefer versus reject watchful waiting approaches to guide clinical decision-making.

Triangulation of pharmacoepidemiology and laboratory science to tackle otic quinolone safety

Background

The scientific method requires studies with high internal and external validity. Though both are necessary, they do not go hand‐in‐hand: The more controlled a study is to enhance internal validity, the less applicable to real‐world clinical care, and vice versa. In the many instances where evidence from clinical trials is not available, scientific inference must rely on more extreme approaches on this spectrum, such as mechanistic (limited generalizability/strong bias control) and real‐world evidence (RWE) studies (higher generalizability/lesser bias control).

Objectives

Illustrate how triangulating mechanistic and RWE studies can enhance scientific inference by delivering the supporting evidence for both.

Methods

We describe our research on an unexpected and highly unlikely drug safety issue: the risk of tympanic membrane (TM) perforations resulting from otic quinolone therapy. Tightly controlled laboratory studies using cell culture and rodent models were complemented with pharmacoepidemiological studies of real‐world data to translate mechanistic findings and corroborate RWE.

Results

We present a cascade of mechanistic and RWE studies investigating fibroblast cytotoxicity, delayed healing of perforated TMs, and spontaneous TM perforations after otic quinolone exposure, all suggesting local tissue toxicity.

Conclusion

Triangulation of mechanistic and RWE studies allowed incremental progress toward robust evidence on otic quinolone toxicity.

Efficacy of Topical Epinephrine in Tympanoplasty

OBJECTIVES/HYPOTHESIS

To compare the hemostatic effects of commonly used concentrations of topical epinephrine in tympanoplasty.

STUDY DESIGN

Prospective, randomized, controlled clinical trial.

METHODS

Patients undergoing tympanoplasty were randomized to receive topical epinephrine at 1:1,000 or 1:10,000. With the investigators blinded, hemostasis was assessed with a modified Boezaart scale. Vasoconstriction was measured by laser Doppler. Blood pressure and pulse were tracked.

RESULTS

Thirty patients, 4 to 84 years old, were studied, with 15 patients per group. Boezaart scores dropped a mean of 67% and 62% with 1:1,000 and 1:10,000, respectively (P = .44). Capillary blood flow decreased a mean of 50.4% and 50.9% with 1:1,000 and 1:10,000, respectively (P = .95). The mean change in heart rate and mean arterial pressure after topical epinephrine exposure were -4.9 and -0.73 beats per minute (P = .15), and -0.60 and -0.73 mmHg (P = .96) for 1:1,000 and 1:10,000 respectively. No adverse events occurred in either group.

CONCLUSIONS

Topical epinephrine at 1:10,000 has hemostatic efficacy comparable to 1:1,000 in tympanoplasty. Although both concentrations appear safe, use of topical epinephrine 1:10,000 should be considered over 1:1,000 to minimize the potential for adverse events.

LEVEL OF EVIDENCE

2 Laryngoscope, 2021.

Association of US Food and Drug Administration Removal of Indications for Use of Oral Quinolones With Prescribing Trends

IMPORTANCE

In May 2016, due to concerns of the risks outweighing the benefits, the US Food and Drug Administration (FDA) removed systemic quinolones' indications for acute, uncomplicated urinary tract infection (uUTI), acute sinusitis (AS), and acute exacerbation of chronic obstructive pulmonary disease (AE-COPD). How the change influenced oral quinolone use is unknown.

OBJECTIVE

To assess the association of oral quinolone safety warnings and indication restrictions with use.

DESIGN, SETTING, AND PARTICIPANTS

This interrupted time series (January 2015-November 2018) analysis of the monthly prevalence of oral quinolone-treated infection episodes used a national sample of privately insured patients in outpatient care from the IBM MarketScan Database and included adults with antibiotic treatment of new uUTI, AS, or AE-COPD episodes, excluding patients with conditions that complicate infections, previous hospitalization, or other infections.

EXPOSURES

Time before and after May 2016 when the FDA mandated label changes.

MAIN OUTCOMES AND MEASURES

Monthly oral quinolone use prevalence by each condition before and after the label changes, overall and stratified by prescriber specialty.

RESULTS

In January 2015, quinolone prevalence among antibiotic-treated uUTI episodes (n = 652 235) was 41.6% (95% CI, 40.6%-42.5%); AS (n = 1 742 248) was 8.3% (95% CI, 7.9%-8.6%), and AE-COPD (n = 22 817) was 31.9% (95% CI, 30.3%-33.4%). Before the label changes, trends in monthly quinolone prevalence were nearly flat. The month of the label changes we noted an immediate reduction for uUTI (-7.2%; 95% CI, -8.6% to -5.8%); and to a lesser extent for AS (-1.2%; 95% CI, -1.5% to -0.9%) and AE-COPD (-2.6%; 95% CI, -4.1% to -1.1%), and continued monthly declines thereafter. Falsification tests confirmed an immediate decrease after the label change of quinolone use for uUTI but more obscured effects for AS and AE-COPD. Treatment shifted mostly to first-line (eg, nitrofurantoin in uUTI, amoxicillin in AS, macrolides in AE-COPD) and other second-line agents but use of not recommended antibiotics also increased (eg, tetracyclines in AE-COPD). Prescribing preferences varied, but significant reductions were seen across all prescriber specialties. At the end of the study period, quinolone was used for 19.2% of treated uUTIs, 2.9% of treated AS, and 14.6% of treated AE-COPD episodes.

CONCLUSIONS AND RELEVANCE

Label changes and their announcements was associated with an immediate reduction in oral quinolone use for uUTI and to a lesser extent for AS and AE-COPD. Quinolones continued to contribute a considerable proportion of treatments for uUTI and AE-COPD episodes at the end of the study period, pointing to opportunities for further improvement.

Prevalence of occult cochlear basal turn patency

BACKGROUND

Perilymph gusher (PLG) is a rare complication of otologic surgery attributed to a communication between the cochlea and the internal auditory canal (IAC). Subtle patency between the cochlear basal turn and IAC has recently been identified on computed tomography (CT) as a risk factor, specifically when the defect is > 0.75 mm.

OBJECTIVES

Investigate the prevalence of radiographic cochlear basal turn patency.

MATERIALS AND METHODS

Patients with CT of the temporal bones and inner ears interpreted as "normal" were included. An otologist and a radiologist independently reviewed CTs to measure radiographic dehiscence in an oblique plane along the interface of the cochlea and IAC. Known PLGs were excluded.

RESULTS

Two hundred and ten ears were included (88 conductive or mixed hearing loss, 62 sensorineural hearing loss, 41 audiometrically normal ears). 71 ears (33.8%) were radiographically patent. Mean defect width was 0.41 mm (0.15-0.7 mm). Defect width was not associated with type of hearing loss, age, or gender. No defects were wider than 0.75 mm.

CONCLUSIONS

Radiographic patency of the cochlear basal turn may be present in patients with hearing loss and normal hearing, but patency > 0.75 mm (i.e. risk for PLG) is rare.

Clinical Practice Guideline: Ménière's Disease Executive Summary

OBJECTIVE

Ménière's disease (MD) is a clinical condition defined by spontaneous vertigo attacks (each lasting 20 minutes to 12 hours) with documented low- to midfrequency sensorineural hearing loss in the affected ear before, during, or after one of the episodes of vertigo. It also presents with fluctuating aural symptoms (hearing loss, tinnitus, or ear fullness) in the affected ear. The underlying etiology of MD is not completely clear, yet it has been associated with inner ear fluid volume increases, culminating in episodic ear symptoms (vertigo, fluctuating hearing loss, tinnitus, and aural fullness). Physical examination findings are often unremarkable, and audiometric testing may or may not show low- to midfrequency sensorineural hearing loss. Imaging, if performed, is also typically normal. The goals of MD treatment are to prevent or reduce vertigo severity and frequency; relieve or prevent hearing loss, tinnitus, and aural fullness; and improve quality of life. Treatment approaches to MD are many, and approaches typically include modifications of lifestyle factors (eg, diet) and medical, surgical, or a combination of therapies.

PURPOSE

The primary purpose of this clinical practice guideline is to improve the quality of the diagnostic workup and treatment outcomes of MD. To achieve this purpose, the goals of this guideline are to use the best available published scientific and/or clinical evidence to enhance diagnostic accuracy and appropriate therapeutic interventions (medical and surgical) while reducing unindicated diagnostic testing and/or imaging.

Clinical Practice Guideline: Ménière's Disease

OBJECTIVE

Ménière's disease (MD) is a clinical condition defined by spontaneous vertigo attacks (each lasting 20 minutes to 12 hours) with documented low- to midfrequency sensorineural hearing loss in the affected ear before, during, or after one of the episodes of vertigo. It also presents with fluctuating aural symptoms (hearing loss, tinnitus, or ear fullness) in the affected ear. The underlying etiology of MD is not completely clear, yet it has been associated with inner ear fluid (endolymph) volume increases, culminating in episodic ear symptoms (vertigo, fluctuating hearing loss, tinnitus, and aural fullness). Physical examination findings are often unremarkable, and audiometric testing may or may not show low- to midfrequency sensorineural hearing loss. Conventional imaging, if performed, is also typically normal. The goals of MD treatment are to prevent or reduce vertigo severity and frequency; relieve or prevent hearing loss, tinnitus, and aural fullness; and improve quality of life. Treatment approaches to MD are many and typically include modifications of lifestyle factors (eg, diet) and medical, surgical, or a combination of therapies.

PURPOSE

The primary purpose of this clinical practice guideline is to improve the quality of the diagnostic workup and treatment outcomes of MD. To achieve this purpose, the goals of this guideline are to use the best available published scientific and/or clinical evidence to enhance diagnostic accuracy and appropriate therapeutic interventions (medical and surgical) while reducing unindicated diagnostic testing and/or imaging.

The Effects of Steroids on Survival of Mouse and Human Tympanic Membrane Fibroblasts

OBJECTIVE

Tympanic membrane (TM) fibroblast cytotoxicity of quinolone ear drops is enhanced by dexamethasone and fluocinolone. Hydrocortisone has not been evaluated. We aimed to assess the effects of these 3 steroids on mouse and human TM fibroblast survival.

STUDY DESIGN

In vitro.

SETTING

Academic laboratory.

SUBJECTS AND METHODS

Mouse and human TM fibroblasts were exposed to hydrocortisone, dexamethasone, or fluocinolone at concentrations in commercial ear drops (1%, 0.1%, or 0.025%, respectively) and at steroid potency equivalents (1%, 0.033%, or 0.0033%, respectively), or dilute ethanol (control), twice within 24 hours or 4 times within 48 hours for 2 hours each time. Cells were observed with phase-contrast microscopy until the cytotoxicity assay was performed.

RESULTS

Mouse and human TM fibroblasts treated with any of the steroids had lower survival after 24 and 48 hours compared to control (all P < .0001). After 24 hours, viability of mouse fibroblasts treated with the steroids was not different (P > .05), while treatment with hydrocortisone decreased human TM fibroblast viability (P < .0001). After 48 hours, at concentrations found in ear drops and at equivalent steroid potency, dexamethasone and fluocinolone had similar survival in mouse and human fibroblasts (all P > .05), but hydrocortisone had lower survival in both mouse (P = .02 and P < .0001) and human (P < .0001) fibroblasts. Phase-contrast images mirrored the cytotoxicity findings.

CONCLUSION

Steroids found in commercial ear drops reduce survival of mouse and human TM fibroblasts. Hydrocortisone appears to be more cytotoxic than the more potent steroids, dexamethasone and fluocinolone. These findings should be considered when assessing clinical outcomes of ototopical preparations.

Cytotoxicity of Ear Drop Excipients in Human and Mouse Tympanic Membrane Fibroblasts

Objective

Commercial ear drops contain ingredients reported to be inactive. We sought to evaluate such excipients for possible cytotoxicity on human and mouse tympanic membrane (TM) fibroblasts.

Study Design

Prospective, in vitro.

Setting

Tertiary academic center.

Subjects and Methods

Mouse and human TM fibroblasts were treated with 1:10 dilutions of benzalkonium chloride (BKC) 0.0025%, 0.006%, or 0.01%; benzyl alcohol 0.9%; polysorbate 80 (PSB) 2.5%; glycerin 2.4%; povidone 0.2%; or water (control), twice within 24 hours or 4 times within 48 hours, for 2 hours each time. Cells were placed back in growth media after the treatments. Cells were observed with phase-contrast microscopy until the cytotoxicity assay was performed.

Results

Mouse fibroblasts had lower survival in only the PSB-treated cells compared to the control ( P < .0001) after 24 hours. After 48 hours, PSB killed nearly all mouse fibroblasts ( P < .0001). BKC decreased fibroblast survival in a dose-dependent manner ( P < .001). In human TM fibroblasts, all excipients except povidone and benzyl alcohol after 24 hours and povidone after 48 hours reduced cell survival compared to control ( P = .012 to P < .0001). The cytotoxicity of BKC in human TM fibroblasts was also dose dependent (<.0001). PSB was less cytotoxic to human fibroblasts. Phase-contrast images mirrored the cytotoxicity findings.

Conclusion

Polysorbate 80 and benzalkonium chloride, at concentrations found in commercial ear drops, may be cytotoxic to human and mouse TM fibroblasts. “Inactive” ingredients may need to be considered when evaluating clinical outcomes with commercial ear drops.

Appropriateness of Otic Quinolone Use among Privately Insured US Patients

Objective

Considering emerging safety concerns involving otic quinolones, we assessed the extent of otic quinolone use for questionable indications.

Study Design

Descriptive cross-sectional study of a national sample of privately insured patients.

Setting

Outpatient encounters in the United States.

Subjects and Methods

Children and adults with outpatient pharmacy-dispensing claims for new prescriptions of otic or ophthalmic quinolones in 2017 were identified within the IBM MarketScan Commercial Claims & Encounters and the Medicare Supplemental Database. Each dispensing ≥30 days apart constituted a unique episode. Only claims with supporting ear-related diagnoses on outpatient encounters ±3 days of dispensing were considered. Ophthalmic drops were excluded if eye-related diagnoses were found ±30 days. Prescribing was classified as appropriate, questionable, or undetermined.

Results

We found 214,897 episodes in 200,270 patients. Adults were twice as likely as children to have otic treatment with questionable indications (6.2% vs 3.0%). Sensitivity analyses with broader time windows to ascertain diagnoses showed similar proportions of questionable use. Otalgia and cerumen impaction constituted 90% of questionable indications. Family physicians (6.8%) and internists (8.0%) had higher percentages of questionable use than other specialties.

Conclusion

Based on the demonstrated risks of quinolone ear drops, opportunities exist to decrease otic quinolone use, especially in adults.

Cochlear basal turn patency in unrecognized perilymph gushers

OBJECTIVES

Perilymph gusher (PLG), an uncommon complication of otologic surgery, has been attributed to communication between the cochlea and the internal auditory canal (IAC). Subtle osseous defects may be missed on routine review of computed tomography (CT). This study aimed to quantify cochlear basal turn patency not seen on axial CT in patients with PLG and compare those against patients without intraoperative PLG.

METHODS

Ears that underwent cochlear implantation or stapedotomy with preoperative helical CT that was interpreted as "normal" at a tertiary referral center. An otologist and a radiologist independently and in a blinded fashion measured the dimensions of cochlear basal turn patency on CT images in oblique plane and parasagittal planes along the interface of the cochlea and IAC fundus.

RESULTS

Sixty-one ears were reviewed, including 3 with surgically confirmed PLGs and 12 with apparent dehiscence without a PLG. Mean defect width with PLG was 0.83 mm (range 0.75-0.9 mm) and without PLG was 0.43 mm (range 0.3-0.65 mm, p = 0.011). A greater proportion of PLGs occurred in ears with defects (3 of 15) than in ears without (0 of 46, p = 0.013). Using a cutoff of 0.75 mm, a greater proportion of PLGs occurred with defect width >0.75 mm (3 of 3) than in defects <0.75 mm (0 of 12, p = 0.022).

CONCLUSIONS

CT dehiscence between the IAC and cochlear basal turn, particularly with a width > 0.75 mm, should be considered a risk for PLG with stapedotomy or cochlear implantation.

Prophylactic antibiotics in head and neck free flap surgery: A novel protocol put to the test

OBJECTIVE

Recent evidence supports the use of ampicillin-sulbactam as a favored choice for antibiotic prophylaxis following head and neck free flap reconstructive surgery. However, there is a paucity of evidence guiding the optimal duration of antibiotic prophylaxis. The aim of this study is to compare the infection rates of short courses of ampicillin-sulbactam versus extended courses of various antibiotics in head and neck free flap reconstructive surgery.

METHODS

This is a retrospective cohort study conducted from 2012 to 2017 at a tertiary academic center on 266 consecutive patients undergoing head and neck surgery with free flap reconstruction. The primary outcome measure was the rate of any infection within 30 days of surgery.

RESULTS

There were 149 patients who received antibiotic prophylaxis for an extended duration of at least seven days. 117 patients received a short course of antibiotics defined as 24 h for non-radiated patients and 72 h for radiated patients. Postoperative infections occurred in 45.9% of patients, of which 92.6% occurred at surgical sites. There was no significant difference in terms of postoperative infection rate between patients receiving an extended duration of antibiotics versus a short duration (p = 0.80). This held true for subgroups of surgical site infections (p = 0.38) and distant infections (p = 0.59 for pneumonia and p = 0.76 for UTI). Risk factors for infections were identified as hypothyroidism (p = 0.047) and clean contaminated wound classification (p = 0.0002).

CONCLUSION

Shorter duration of ampicillin-sulbactam prophylaxis in free flap reconstruction of head and neck defects does not negatively affect postoperative infection rates.

LEVEL OF EVIDENCE

Level 2b.

The Adenoid Microbiome in Recurrent Acute Otitis Media and Obstructive Sleep Apnea

OBJECTIVE

To compare the microbial flora of adenoids from patients with recurrent acute otitis media (AOM) and patients with obstructive sleep apnea (OSA).

MATERIALS AND METHODS

This study was prospective and controlled. Adenoids were obtained from children undergoing adenoidectomy for recurrent AOM (n=7) or OSA (n=13). Specimens were processed for total deoxyribonucleic acid (DNA) isolation. 16s DNA 454-pyrosequencing was performed on AOM (n=5) and OSA (n=5) specimens. All specimens were analyzed by real-time polymerase chain reaction for the quantification of the oral commensal bacteria, Streptococcus salivarius.

RESULTS

All adenoid specimens had evidence of microbes. Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus were among the dominant species in all samples. S. salivarius, Prevotella sp. and Terrahaemophilus aromaticivorans were more common on adenoids from OSA patients (p<0.05). Bradyrhizobium sp. was more common on adenoids from patients with recurrent AOM (p<0.05). The microbial profiles associated with recurrent AOM were different from, but overlapped with OSA. S. salivarius quantified by real-time PCR was not different between the two groups.

CONCLUSION

Microbes are present on all adenoid specimens, though the microbial profile differs between recurrent AOM and OSA. The clinical significance of these differences remains to be determined.

Efficacy of the mini-meatoplasty

OBJECTIVES

The lateral meatoplasty is a well-described technique for widening the lateral external auditory meatus. After bony canalplasty, the external auditory meatus may need to be enlarged to accommodate an expanded tympanic ring. In this study, we introduce a novel meatoplasty technique for use during canalplasty and describe its efficacy in widening the external auditory meatus.

METHODS

Patients undergoing at least 180-degree bony canalplasty and mini-meatoplasty at a tertiary care facility were enrolled. Meatus diameter was measured before and after mini-meatoplasty using Shea aural speculums and Hegar dilators.

RESULTS

Nineteen patients were enrolled. Mean preoperative speculum size was 6.1 mm (range 3.5-7.5 mm). All postoperative speculum sizes were 8 mm (P < .0001). Mean preoperative and postoperative Hegar dilator sizes were 10.6 mm (range 7-14 mm) and 16.2 mm (range 13-19 mm), respectively (P < .0001). The mean increase in aural speculum and Hegar dilator sizes were 1.9 mm (range 0.5-3.5 mm) and 5.7 mm (range 3-10 mm), respectively (P < .0001).

CONCLUSIONS

The mini-meatoplasty is a novel and effective technique for widening the external auditory meatus after bony canalplasty.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:1294-1298, 2020.

Efficacy of common reagents for killing ticks in the ear canal

Objective

To determine if widely available solutions can effectively kill ticks that may be found in the human ear canal.

Methods

This study was prospective, controlled and blinded animal study. Lone star ticks (Amblyomma americanum), both nymphal and adult, were submerged in one of four preparations (acetone, isopropyl alcohol 70%, ethanol 95%, or 4% lidocaine) in test tubes (n = 20 per group) for 20 minutes. Ticks were agitated by intermittent probing. Activity of the nymphal ticks was directly observed while those of the adult ticks was video‐recorded during the exposure period. Two blinded investigators viewed the videos of adult ticks and during the exposure period to determine the time until death (ie, movement cessation). Mortality was assessed immediately after exposure, and confirmed 24 and 48 hours after exposure.

Results

Acetone killed ticks most rapidly (nymph mean time = 185.1 s; adult mean time = 562.9 s). Isopropyl alcohol 70% (nymphs, 328.9 s; adults, 1128.4 s) and ethanol 95% (nymphs, 294 s; adults, 1129.4 s) took longer to kill the ticks. All ticks treated with 4% lidocaine survived. These differences were significant (nymphs, P < .0001; adults, P < .0001).

Conclusions

Acetone was the fastest acting and most effective reagent, followed by ethanol and isopropyl alcohol. These solutions may prove useful in otoacariasis with an intact tympanic membrane.

Level of Evidence

N/A

Risk of sudden sensorineural hearing loss in adults using phosphodiesterase type 5 inhibitors: Population-based cohort study

PURPOSE

The objective of the study was to determine the risk of sudden sensorineural hearing loss (SNHL) associated with use of phosphodiesterase type 5 (PDE5) inhibitors.

METHODS

We conducted a retrospective cohort study in the MarketScan Commercial Claims and Encounters Database including adult men who initiated a PDE5 inhibitor (n = 377,722) and 1,957,233 nonusers between 1998 and 2007. Periods of drug exposure were assessed on a weekly basis based on pharmacy billing records, assuming use of 1 dose per week (current use). Incident sudden SNHL was defined based on inpatient or outpatient visits with International Classification of Diseases, Ninth Revision, Clinical Modification codes 389.1x, 389.2x, or 388.2 plus ≥2 procedure codes for audiometric hearing testing within ±30 days of sudden SNHL diagnosis. We used age- and propensity score-adjusted Cox proportional hazards model to evaluate the risk of sudden SNHL during periods of current or recent use compared with that of nonuse. We conducted sensitivity analyses by varying the assumed drug utilization frequency and sudden SNHL case definition.

RESULTS

We evaluated 1233 sudden SNHL cases, resulting in an incidence of 4.35, 5.58, and 2.38 per 10,000 person-years for current, recent, and nonuse of PDE5 inhibitors, respectively. Compared with nonuse, the adjusted hazard ratio was 1.25 (1.01-1.55) for current use with a risk difference of 1.97 (1.12-2.82) per 10,000 person-years. For recent use, the adjusted hazard ratio was 1.60 (1.33-1.94) and risk difference was 3.19 (2.24-4.14). Estimates were consistent across the sensitivity analyses.

CONCLUSIONS

Use of PDE5 inhibitors is associated with a small but significantly increased risk of sudden SNHL.

Cytotoxicity of Ciprofloxacin and Steroids in Mouse Tympanic Membrane Fibroblasts

Objective

Ciprofloxacin, commonly given as eardrops, has been shown to adversely affect tympanic membrane fibroblasts. Dexamethasone potentiates this effect. A newly available eardrop contains ciprofloxacin and fluocinolone, a more potent steroid. We evaluated the cytotoxic effects of this preparation on mouse tympanic membrane fibroblasts.

Study Design

Prospective, in vitro.

Setting

Academic laboratory.

Subjects and Methods

In experiment 1, fibroblasts were exposed to 1:10 dilutions of commercially available 0.3% ofloxacin, 0.3% ciprofloxacin, 0.3% ciprofloxacin + 0.1% dexamethasone, 0.3% ciprofloxacin + 0.025% fluocinolone, or dilute hydrochloric acid (control), twice within 24 hours. In experiment 2, cells were also treated with the dilutions of the pure form of dexamethasone 0.1% or fluocinolone 0.025%, alone and in combination with ofloxacin or ciprofloxacin. Cells were exposed to the solutions for 2 hours each time and were placed back in growth media after the treatments. Cells were observed with phase-contrast microscope until the cytotoxicity assay was performed.

Results

Survival of fibroblasts treated with ofloxacin was not different from the control. Fibroblasts treated with ciprofloxacin, ciprofloxacin + dexamethasone, or ciprofloxacin + fluocinolone had much lower survival (all P < .0001). Cells treated with ciprofloxacin + fluocinolone had lower survival than ciprofloxacin ( P < .0001) and ciprofloxacin + dexamethasone ( P = .0001). Steroids alone also decreased fibroblast survival compared to control ( P < .0001). The combination of dexamethasone or fluocinolone with ciprofloxacin, but not ofloxacin, further decreased fibroblast survival ( P < .0001). Phase-contrast images mirrored the cytotoxicity findings.

Conclusion

Tympanic membrane fibroblast cytotoxicity of ciprofloxacin is potentiated by corticosteroids. This effect may be deleterious when treating a healing perforation but beneficial when treating granulation tissue on the tympanic membrane.

Safety and efficacy of ebselen for the prevention of noise-induced hearing loss: a randomised, double-blind, placebo-controlled, phase 2 trial

BACKGROUND

Noise-induced hearing loss is a leading cause of occupational and recreational injury and disease, and a major determinant of age-related hearing loss. No therapeutic agent has been approved for the prevention or treatment of this disorder. In animal models, glutathione peroxidase 1 (GPx1) activity is reduced after acute noise exposure. Ebselen, a novel GPx1 mimic, has been shown to reduce both temporary and permanent noise-induced hearing loss in preclinical studies. We assessed the safety and efficacy of ebselen for the prevention of noise-induced hearing loss in young adults in a phase 2 clinical trial.

METHODS

In this single-centre, randomised, double-blind, placebo-controlled phase 2 trial, healthy adults aged 18-31 years were randomly assigned (1:1:1:1) at the University of Florida (Gainsville, FL, USA) to receive ebselen 200 mg, 400 mg, or 600 mg, or placebo orally twice daily for 4 days, beginning 2 days before a calibrated sound challenge (4 h of pre-recorded music delivered by insert earphones). Randomisation was done with an allocation sequence generated by an independent third party. The primary outcome was mean temporary threshold shift (TTS) at 4 kHz measured 15 min after the calibrated sound challenge by pure tone audiometry; a reduction of 50% in an ebselen dose group compared with the placebo group was judged to be clinically relevant. All participants who received the calibrated sound challenge and at least one dose of study drug were included in the efficacy analysis. All randomly assigned patients were included in the safety analysis. This trial is registered with ClinicalTrials.gov, number NCT01444846.

FINDINGS

Between Jan 11, 2013, and March 24, 2014, 83 participants were enrolled and randomly assigned to receive ebselen 200 mg (n=22), 400 mg (n=20), or 600 mg (n=21), or placebo (n=20). Two participants in the 200 mg ebselen group were discontinued from the study before the calibrated sound challenge because they no longer met the inclusion criteria; these participants were excluded from the efficacy analysis. Mean TTS at 4 kHz was 1·32 dB (SE 0·91) in the 400 mg ebselen group compared with 4·07 dB (0·90) in the placebo group, representing a significant reduction of 68% (difference -2·75 dB, 95% CI -4·54 to -0·97; p=0·0025). Compared with placebo, TTS at 4 kHz was non-significantly reduced by 21% in the 200 mg ebselen group (3·23 dB [SE 0·91] vs 4·07 dB [0·90] in the placebo group; difference -0·84 dB, 95% CI -2·63 to 0·94; p=0·3542) and by 7% in the 600 mg ebselen group (3·81 dB [0·90] vs 4·07 dB [0·90] in the placebo group; difference -0·27, 95% CI -2·03 to 1·50; p=0·7659). Ebselen treatment was well tolerated across all doses and no significant differences were seen in any haematological, serum chemistry, or radiological assessments between the ebselen groups and the placebo group.

INTERPRETATION

Treatment with ebselen was safe and effective at a dose of 400 mg twice daily in preventing a noise-induced TTS. These data lend support to a role of GPx1 activity in acute noise-induced hearing loss.

FUNDING

Sound Pharmaceuticals.

Microflora of Retained Intracochlear Electrodes from Infected Cochlear Implants

Objectives Cochlear implant infections may be refractory to medical management and require device removal with subsequent reimplantation. During device removal, the intracochlear electrode array is commonly left in place to prevent obliteration of the cochlear lumen. If the electrode is colonized with pathogens, this risks contaminating the replacement implant. In this study, we compare the microorganisms detected on infected cochlear implants against those on the retained electrode using culture and microbial gene-sequencing techniques. Study Design Prospective single-cohort study. Setting Tertiary medical center. Subjects and Methods Six patients with refractory cochlear implant infections had the receiver-stimulator and extracochlear electrode removed to facilitate treatment of the infection. The intracochlear electrode was removed at (delayed) reimplantation. Implant specimens were analyzed by microbial culture and 16S DNA gene sequencing. Results Staphylococcus aureus was the organism most commonly identified. None of the 6 patients' intracochlear electrodes yielded microbes by culture. Two intracochlear electrodes revealed bacterial species, and 1 revealed fungal species by gene sequencing. There was no correlation between the microbes on the infected extracochlear implants and the retained intracochlear electrodes. All subjects underwent reimplantation after resolution of their infections. One of 6 subjects developed a second infection after reimplantation, with S aureus in the primary and secondary infections. Conclusions The intracochlear electrodes of infected cochlear implants carry a low microbial burden. Preserving intracochlear electrodes upon removal of infected cochlear implants appears to carry a low risk of contaminating a replacement cochlear implant.

Mitochondria-Targeted Antioxidant Mitoquinone Reduces Cisplatin-Induced Ototoxicity in Guinea Pigs

Objective To determine if mitoquinone (MitoQ) attenuates cisplatin-induced hearing loss in guinea pigs. Study Design Prospective and controlled animal study. Setting Academic, tertiary medical center. Subjects and Methods Guinea pigs were injected subcutaneously with either 5 mg/kg MitoQ (n = 9) or normal saline (control, n = 9) for 7 days and 1 hour before receiving a single dose of 10 mg/kg cisplatin. Auditory brainstem response thresholds were measured before MitoQ or saline administration and 3 to 4 days after cisplatin administration. Results Auditory brainstem response threshold shifts after cisplatin treatment were smaller by 28 to 47 dB in guinea pigs injected with MitoQ compared with those in the control group at all tested frequencies (4, 8, 16, and 24 kHz, P = .0002 to .04). Scanning electron microscopy of cochlear hair cells showed less outer hair cell loss and damage in the MitoQ group. Conclusion MitoQ reduced cisplatin-induced hearing loss in guinea pigs. MitoQ appears worthy of further investigation as a means of preventing cisplatin ototoxicity in humans.

Fetal Central Auditory System Metabolic Response to Cochlear Implant Stimulation

OBJECTIVES: The purpose of this study was to examine the effects of profound auditory deprivation and its treatment by cochlear implantation and stimulation on the metabolic activity of the central auditory system in fetal sheep.

METHODS: Six ovine fetuses at 85% to 90% gestation were bilaterally deafened by kanamycin perfusion and unilaterally implanted with cochlear electrode arrays. Half of the implanted animals were stimulated with an extrauterine sound processor, and half were not. Four animals served as hearing controls. One week postoperatively, central nervous system metabolic activity was evaluated in ambient laboratory noise by quantitative autoradiography using 14C-deoxyglucose.

RESULTS: Kanamycin perfusion deafened all treated animals as verified by auditory brainstem response and scanning electron microscopy. Glucose utilization in the inferior colliculus was markedly lower in deafened and unstimulated animals relative to hearing controls. Glucose utilization in implanted-stimulated animals was similar to normal controls.

CONCLUSIONS: Changes in central auditory system metabolic activity associated with congenital deafness may be minimized by prompt auditory habilitation.

Prevention of biofilm formation by polyquaternary polymer

OBJECTIVE

Biofilm formation has been linked to device-associated infections in otolaryngology. This study was conducted to determine if a microbicidal polyquaternary polymer, poly diallyl-dimethylammonium chloride (pDADMAC) could prevent biofilm development by pathogens that commonly cause implant infections, Staphylococcus aureus and Pseudomonas aeruginosa.

METHODS AND MATERIALS

This study was prospective and controlled in vitro microbiological study. Polyurethane tubes (20 per treatment) with and without a polyquaternary polymer coating were briefly exposed to plasma or saline, then to S. aureus or P. aeruginosa. Polyurethane tubes were incubated in growth media. After 4 days, antibiotics were added to kill planktonic bacteria. S. aureus or P. aeruginosa bacterial counts and scanning electron microscopy (SEM) were performed.

RESULTS

S. aureus biofilm counts were reduced by 8 logs on tubes with polyquaternary polymer coating compared to the control tubes, either with plasma (3.67E+01 ± 7.30E+01 vs 1.08E+09 ± 4.81E+08; P < 0.0001) or without plasma (3.70E+00 ± 1.10E+01 vs 6.50E+08 ± 2.79E+08; P < 0.0001). P. aeruginosa biofilm formation was also reduced on tubes with polyquaternary polymer, either with plasma (2.90E+07 ± 1.71E+07 vs 9.16E+08 ± 4.43E+08; P < 0.0001) or without plasma (2.50E+07 ± 9.54E+06 vs 3.35E+08 ± 2.18E+08; P < 0.001), but the reduction was only 1 log. On control tubes, plasma promoted S. aureus (1.08E+09 ± 4.81E+08 vs 6.05E+08 ± 2.79E+08; P < 0.0001) and P. aeruginosa (9.16E+08 ± 4.43E+08 vs 3.35E+08 ± 2.18E+08; P < 0.0001) bacterial counts but not on the tubes coated with polyquaternary polymer.

CONCLUSIONS

Incorporation of the microbicidal polyquaternary polymer, pDADMAC, into polyurethane dramatically inhibits S. aureus biofilm formation. Further research is warranted to evaluate the efficacy and safety of this technology in otolaryngologic implants.

Efficacy of antibiotic prophylaxis prior to tympanoplasty for contaminated cholesteatoma

OBJECTIVES

To evaluate the efficacy of combined antistaphylococcal and antipseudomonal preoperative antibiotics for preventing surgical site infections following tympanoplasty and mastoidectomy with contaminated cholesteatoma.

STUDY DESIGN

Retrospective chart review.

METHODS

Medical records of patients who underwent tympanoplasty ± mastoidectomy for cholesteatoma were reviewed. Only cases considered to have contaminated or dirty surgical fields were included. The primary outcome measure was occurrence of postoperative surgical site infections, perichondritis, pinna abscess, periotic cellulitis, or periotic abscess requiring systemic antibiotic therapy or surgical intervention.

RESULTS

The charts of 326 patients who underwent tympanoplasty ± mastoidectomy were reviewed. Of those, 195 met inclusion criteria. Preoperative antibiotics included clindamycin and ceftazidime or gentamicin. Patients treated with no perioperative antibiotics had a surgical site infection rate of 11%, and those treated with perioperative antibiotics had a rate of 1% (P = 0.02).

CONCLUSION

Administration of preoperative antibiotics to cover staphylococcal and pseudomonal species may prevent surgical site infections with tympanoplasty ± mastoidectomy for contaminated cholesteatoma.

LEVEL OF EVIDENCE

4. Laryngoscope, 126:2363-2366, 2016.

Dietary supplement comprised of β-carotene, vitamin C, vitamin E, and magnesium: failure to prevent music-induced temporary threshold shift

This study examined potential prevention of music-induced temporary threshold shift (TTS) in normal-hearing participants. A dietary supplement composed of β-carotene, vitamins C and E, and magnesium was assessed using a randomized, placebo-controlled, double-blind study design. Dosing began 3 days prior to the music exposure with the final dose consumed approximately 30-min pre-exposure. There were no group differences in post-exposure TTS or music-induced decreases in distortion product otoacoustic emission (DPOAE) amplitude. Transient tinnitus was more likely to be reported by the treatment group, but there were no group differences in perceived loudness or bothersomeness. All subjects were monitored until auditory function returned to pre-exposure levels. Taken together, this supplement had no effect on noise-induced changes in hearing. Recommendations for future clinical trials are discussed.

Preoperative antibiotic and steroid therapy and hearing loss caused by semicircular canal transection in pseudomonas otitis media

OBJECTIVE: The purpose of this experiment was to determine whether preoperative administration of antibiotics and corticosteroids can attenuate the severity of hearing loss (HL) with semicircular canal (SC) transection in a guinea pig model of Pseudomonas aeruginosa (PA) otitis media (OM).

STUDY DESIGN AND SETTING: Prospective and controlled.

METHODS: OM was induced in 64 pigmented guinea pigs by bilateral, transtympanic injection of PA. Two to 4 days later, 1 horizontal SC was randomly transected. In the 1st series, antibiotic therapy was initiated either immediately before or after surgery. In the 2nd series, all animals received preoperative antibiotics, and half received dexamethasone before surgery. Hearing was tested before and after surgery.

RESULTS: PA was recovered in all ears. SC transection was associated with significant HL. HL was better in animals given antibiotics preoperatively (clicks, 16 versus 32 dB, P = 0.0220). Addition of preoperative steroids did not significantly further reduce HL (7 versus 14 dB for clicks, P = 0.6919).

CONCLUSIONS: HL caused by SC transection in PA OM may be attenuated with preoperative antibiotic therapy in the guinea pig.

Opening plugged tympanostomy tubes: Effect of inner diameter and shaft length

OBJECTIVE: To determine whether tympanostomy tube (TT) inner diameter or shaft length impacts the rate of mucoid plug clearance.

STUDY DESIGN AND SETTING: Ex vivo model. Silicone TTs with different inner-diameters (ID) and shaft-length (SL) pairings (1.14 mm ID × 12 mm SL versus 1.14 mm ID × 1 mm SL; 1.14 mm ID × 4.8 mm SL versus 1.32 mm ID × 4.8 mm SL) were plugged with middle-ear mucus (n = 15 per group) and placed in a model ear chamber. Ofloxacin otic solution was instilled into the chamber to cover the plugged TT, and the time to clearance of each plug was recorded.

RESULTS: TTs with larger IDs ( P = 0.019) and greater SLs ( P = 0.033) cleared plugs more rapidly. However, the difference in the percentage of tubes that unplugged was not significant ( P = 0.151).

CONCLUSIONS: Rate of ex vivo TT plug clearance may be altered by changing TT ID and SL.

Biofilm formation in an in vitro model of cochlear implants with removable magnets

Background

Cochlear implant (CI) recesses, such as the removable magnet pocket, appear to harbor more biofilm than smooth surfaces. The aim of this study was to examine the impact of removable magnets on biofilm formation in an in vitro model.

Methods

Silastic models were constructed to represent CIs with and without a magnet pocket and with and without a titanium blank in the pocket. CIs were exposed to a culture of a biofilm forming strain of Staphylococcus aureus. Adherence of planktonic bacteria and biofilm formation were assessed with quantitative bacterial counts and scanning electron microscopy.

Results

Adherent bacterial counts were significantly higher in CI models with an empty magnet pocket ( P = 0.0097). Biofilm formation was significantly lower in CI models without a magnet pocket ( P = 0.0121).

Conclusions

CI magnet pockets harbor bacteria that can increase biofilm development in an in vitro model.

Hearing Loss with Semicircular Canal Transection and Pseudomonas Aeruginosa Otitis Media

OBJECTIVE: To determine if Pseudomonas aeruginosa (PA) otitis media (OM) increases the risk of sensorineural hearing loss (SNHL) with semicircular canal transection in the guinea pig model.

METHODS: PA was injected transtympanically into both middle ears of pigmented guinea pigs. Saline-injected animals served as controls. Two to 4 days after injection, one horizontal semicircular canal was transected and sealed. Hearing was tested using electrocochleography before and after transection.

RESULTS: PA-OM was induced in all PA-injected ears. Five days after semicircular canal transection, click-evoked thresholds were significantly elevated in ears with PA-OM ( P = 0.00009) but not in saline-injected ears ( P = 0.398).

CONCLUSION: Violation of the inner ear in the presence of PA-OM is associated with increased risk of SNHL in the guinea pig.

SIGNIFICANCE: Factors unique to PA infection may be responsible for SNHL with labyrinthine injury in humans with chronic otitis media.

Hearing loss and extent of labyrinthine injury in Pseudomonas otitis media

OBJECTIVES:

To determine if the severity of hearing loss due to semicircular canal transection (SCT) in Pseudomonas otitis media (POM) is a function of the extent of the labyrinthine injury.

METHODS:

POM was induced bilaterally in 45 guinea pigs. After 2 to 4 days, SCT was performed in one 1 on the horizontal canal, the superior canal, or both the horizontal and the superior canals. Auditory-evoked brainstem responses were measured before and after SCT.

RESULTS:

POM was induced bilaterally in all animals. Elevation of click thresholds was found in almost all SCT ears of all 3 groups; however, there were no significant differences between groups. Comparing the SCT ear to the contralateral, control ear, mean hearing losses in the horizontal, superior, and horizontal + superior SCT groups were 23 dB, 27 dB, and 24 dB, respectively.

CONCLUSIONS

Hearing loss does not correlate with extent of labyrinthine injury in POM in the guinea pig. EBM rating: B-2.

Opening Plugged Tympanostomy Tubes: Effect of Biofilm Formation

OBJECTIVES: To determine if the presence of a bacterial biofilm impacts the rate of clearing of mucoid plugs from tympanostomy tubes (TTs).

STUDY DESIGN AND SETTING: Ex vivo model. Stainless steel Reuter Bobbin TTs ( n = 18) were placed in growth medium with Pseudomonas aeruginosa and Streptococcus pneumoniae for 12 days to promote biofilm formation. Tympanostomy tubes ( n = 18) placed in growth medium, without bacteria, for 12 days served as controls. Biofilm formation was assessed by scanning electron microscopy. All TTs were filled with middle ear mucus and allowed to dry, thereby forming a plug. TTs were placed in a model ear chamber, covered with ofloxacin otic solution, and the time to clear each plug was recorded.

RESULTS: Biofilm formation was consistently encountered on TTs exposed to bacteria but in no TTs in the control group. There was a significant effect of the biofilm on plug clearance, favoring TTs without a biofilm ( P = 0.0333). Although there was no significant difference in the proportion of unplugged TTs ( P = 0.264), TTs with a biofilm did not clear plugs as rapidly as TTs without a biofilm ( P = 0.0416).

CONCLUSIONS: The presence of a biofilm may slow the time to clear mucoid TT plugs, but it does not seem to affect the overall proportion of TTs that are unplugged.

Cochlear Implant Magnet Displacement With Minor Head Trauma

Objectives:

Manufacturers have introduced cochlear implants (CIs) with removable magnets to allow for magnetic resonance imaging after placement. The purpose of this study was to describe magnet displacement as a new CI complication and to suggest apossible treatment option to prevent its recurrence.

Study Design:

Retrospective case series.

Methods:

The records of 3 young males who experienced CI magnet dislodgement were reviewed and compared against records from the institutional implant database.

Results:

Magnet displacement was observed only in young males (14% of male children) who received CI with removable magnets. This occurred 13-14 months after CI placement. Magnets were replaced under general anesthesia, and the scalp was bolstered with a dermal allograft. Recurrent magnet dislodgement was encountered in 1 patient, 6 months later.

Conclusions:

Magnet displacement may be a relatively common complication after minor head trauma in pediatric patients with certain CIs that have removable magnets.

Ciprofloxacin Decreases Collagen in Mouse Tympanic Membrane Fibroblasts

Objectives

To determine how collagen production by tympanic membrane fibroblasts is affected by ciprofloxacin at levels found in eardrops.

Study Design

Prospective, controlled, and blinded cell culture study.

Setting

Academic tertiary medical center.

Subjects

Cell culture of mouse fibroblasts.

Methods

A primary fibroblast culture was established from mouse tympanic membranes. Fibroblasts were cultured until they were 75% confluent, then treated with dilute hydrochloric acid (control) or ciprofloxacin (0.01% or 0.3%) for 24 or 72 hours for Western blotting and for 24 or 48 hours for cytotoxicity assay. Cells were observed with phase-contrast microscope. Western blotting was performed for collagen type 1 α1 (collagen 1A1) and α-tubulin.

Results

Fibroblasts treated with 0.01% and 0.3% ciprofloxacin for 24 hours had lower levels of collagen 1A1 ( P = .0005 and P < .0001, respectively) and α-tubulin (both P < .0001) than control fibroblasts. Collagen 1A1 and α-tubulin levels were lower in fibroblasts treated with 0.3% than with 0.01% ciprofloxacin ( P = .02 and P = .014). After 72 hours, 0.3% ciprofloxacin completely eliminated collagen 1A1 and α-tubulin ( P < .001). Cells treated with 0.01% ciprofloxacin for 72 hours also had lower collagen 1A1 ( P < .0001) and α-tubulin ( P = .005) as compared with the control. Seventy-two-hour incubation in 0.01% or 0.3% ciprofloxacin resulted in lower levels of collagen 1A1 ( P = .009 and P < .0001, respectively) and α-tubulin ( P = .007 and P < .0001, respectively) than 24-hour incubation. Cytotoxicity assay and phase-contrast microscopy mirrored these findings.

Conclusions

Treatment of tympanic membrane fibroblasts with 0.3% ciprofloxacin, as found in eardrops, reduces fibroblast viability and collagen and α-tubulin protein levels. These findings could explain tympanic membrane healing problems associated with quinolone eardrops.

Magnetic resonance imaging in a guinea pig model of inner ear decompression sickness and barotrauma

OBJECTIVES/HYPOTHESIS

Scuba diving may cause severe hearing loss and vertigo due to inner ear barotrauma and decompression sickness. These may be difficult to differentiate clinically. Decompression sickness requires costly and potentially dangerous hyperbaric therapy, whereas such treatment may worsen barotrauma. The objective of this study was to assess the potential utility of magnetic resonance imaging to identify and distinguish blood from air in the inner ear, manifestations of barotrauma and decompression sickness, using a guinea pig model.

STUDY DESIGN

Prospective animal trial.

METHODS

Magnetic resonance of the head was performed at 3 Tesla, pre- and postinjection of 2, 4, or 10 μL of air or blood through the round window into the perilymph. With this model, 2 μL has been shown to cause hearing loss. Images were reviewed by a neuroradiologist blinded to the treatment.

RESULTS

All 14 normal ears, five of seven blood- and five of seven air-injected ears, were correctly interpreted. Two blood- and one air-injected ear were interpreted as indeterminate. One air-injected ear was incorrectly interpreted as blood.

CONCLUSIONS

Magnetic resonance reliably distinguishes small volumes of air and blood in the guinea pig inner ear. Magnetic resonance should be evaluated for its utility in the diagnosis of inner ear barotrauma and decompression sickness in scuba divers.

LEVEL OF EVIDENCE

NA Laryngoscope, 126:2106-2109, 2016.