The Effectiveness of Salvage Hyperbaric Oxygen Therapy Following Combined Steroid Therapy for Refractory Sudden Sensorineural Hearing Loss

OBJECTIVE

Hyperbaric oxygen therapy (HBOT) is an accepted treatment option for sudden sensorineural hearing loss (SSNHL), but it is still recommended in combination with corticosteroids. We investigated the efficacy of salvage HBOT in refractory SSNHL that does not respond to corticosteroid combination therapy.

METHODS

Eighty-four patients were included, who had unilateral SSNHL with an improvement of pure-tone average (PTA) less than 10 dB after using intratympanic plus systemic corticosteroids (combined therapy) as the initial therapy. The control group (n = 66) received no further treatment, and the HBOT group (n = 18) received additional treatment with HBOT (10 sessions in total with 2.5 atmospheres absolute for 1 hour).

RESULTS

No differences in PTA or WDS were found between the 2 groups. However, the mean hearing gain in the HBOT group (16.8 ± 4.49 dB) was significantly higher than that in the control group (4.45 ± 1.03 dB) (P = .015). The proportion of patients with hearing recovery (hearing gain of 10 dB or more) after treatment was significantly higher in HBOT group (38.9%) than in the control group (10.6%).

CONCLUSIONS

In patients with refractory SSNHL after steroid combined therapy, salvage HBOT showed a significant effect on hearing gain and recovery rate.

Comparison of the 3D-Exoscope and Operating Microscope in Mastoidectomy

OBJECTIVES

The operating microscope (OM) commonly used in ear surgeries has several disadvantages, including a low depth of field, a narrow field of view, and unfavorable ergonomic characteristics. The exoscope (EX) was developed to overcome these disadvantages. Herein, we compared OM and EX during mastoidectomy and found out the feasibility of the EX.

STUDY DESIGN

Prospective randomized comparative study.

SETTING

Tertiary academic medical center.

PATIENTS

Patients who had mastoidectomy for chronic otitis media with or without cholesteatoma between January 2022 and April 2022.

INTERVENTION

Canal wall-up mastoidectomy (CWUM) or canal wall-down mastoidectomy (CWDM) using OM or EX without endoscope.

MAIN OUTCOME MEASURES

Operative setting time (the time between the end of general anesthesia and incision), operative time (from incision to suture), postoperative audiologic outcomes, perioperative complications, and the decision to switch from EX to OM.

RESULTS

Of 24 patients who were diagnosed with chronic otitis media or cholesteatoma, 12 each were randomly assigned to the OM or EX group. The mean operation time was 175 ± 26.5 minutes and 172 ± 34.6 minutes in the EX and OM group, respectively, which was not significantly different ( p = 0.843). The procedures in the EX group were successfully completed using a three-dimensional (3D)-EX without conversion to OM. All surgeries were completed without any complications. The postoperative difference in the air and bone conduction was 11.2 and 12.4 dB in the EX and OM groups, respectively, which was not significantly different ( p = 0.551).

CONCLUSIONS

EX is comparable to OM in terms of surgical time, complications, and audiologic outcomes following mastoidectomy. The EX system is a potential alternative to OM. However, further improvements are required to overcome some drawbacks (deterioration of image resolution at high magnification, requirement of an additional controller for refocusing).

Drop Attack Treated by Microvascular Decompression of the Superior Vestibular Nerve

We report a case of cochleovestibular neurovascular compressive syndrome (CVCS)-induced drop attack treated with microvascular decompression (MVD) of the superior vestibular nerve. This report discusses the merits of surgical intervention through a review of related literature. A 58-year-old woman was referred to our clinic with a chief complaint of intermittent, strong, right-sided tinnitus lasting for a few seconds immediately prior to drop attack. Magnetic resonance imaging (MRI) showed bilateral neurovascular contact between the anterior inferior cerebellar artery (AICA) and the vestibulocochlear nerve. Based on MRI findings, history of present illness, and response to anticonvulsants, CVCS was suspected, and surgical decompression on the right side was subsequently performed. The patient became asymptomatic immediately after the surgery, and the vestibular-evoked myogenic potentials were normalized. No recurrence was reported during a 1-year follow-up period.

Surgical technique for complicated preauricular sinus: Pilot study of double elliptical excision with coaptation suture

OBJECTIVES

Preauricular sinus (PAS) is a congenital anomaly that can progress to complicated cases with granulation tissue around the PAS area due to skin inflammation. Treatment involves incision and drainage or continuous dressing; however, surgical treatment may be necessary. We evaluated a surgical method for the effective treatment of complicated PAS.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 152 patients with PAS who were treated at a tertiary medical institution between September 2015 and June 2022. Data regarding age, sex, preoperative history related to PAS, a joint operation with a plastic surgeon, operation time, admission duration, follow-up duration, and postoperative complications were collected. The study population was divided into single-excision and double-excision with coaptation suture groups. The clinical characteristics were analyzed and compared between the two groups.

RESULTS

Surgical treatment for PAS was performed in 131 patients (166 ears) in the single-excision group and 21 patients (27 ears) in the double-excision group. The average age was 6.22 ± 4.06 years old, and the male-to-female ratio was similar in the single-excision group (M:F = 68:63) but higher for females in the double-excision group (M:F = 5:16) (p = 0.017). Joint surgeries with a plastic surgeon were more frequent in the double-excision group, and the operation time and admission duration were significantly longer. The preoperative history and postoperative complications (seven cases, 4.6 %) did not differ significantly between the two groups, although there was a higher percentage of complications in the double elliptical excision group.

CONCLUSIONS

Double excision with one or more coaptation sutures is an effective one-step method for complicated PAS with an acceptable aesthetic appearance of the scar, although it requires a longer operation time and admission duration for wound care. Further studies with larger and more diverse patient populations are needed to validate these findings.

Prospective Study of Nonsurgical Auricular Correction According to Timing of Treatment

BACKGROUND AND PURPOSE

Many studies recommend nonsurgical auricular correction during the early postnatal period, when cartilage plasticity is high; however, many patients are not eligible for the procedure. This study compared different timings of nonsurgical auricular correction to investigate benefit after the optimal period for correction.

METHODS

In this prospective study, 53 ears from 35 patients with congenital auricular anomaly were assigned to two groups according to age at correction: the "early-group" with correction within 2 weeks of birth and "late-group" with correction 8 weeks after birth. Aesthetic outcomes, caregiver satisfaction, detachment rates and mean device-wearing periods, were compared.

RESULTS

Thirty-one ears from 20 patients comprised the early-group, and 18 ears from 12 patients comprised the late-group. Mean time to treatment after birth was 9.09 days in the early-group and 134.7 days in the late-group. In the early-group, detachment occurred in 4/31 ears (12.9%), and in the late-group, detachment occurred in 12/18 ears (66.7%), which was statistically significant (p<0.01). The average period of applying devices was 4.7 ± 1.2 weeks in the early-group and 8.5 ± 4.1 weeks in the late-group, with a significantly longer treatment time in the late-group (p=0.001). The early-group had 87.1% "good" results vs. 55.6% in the late-group, with a statistically significant difference.

CONCLUSIONS

The correction period was shorter, detachment rate was lower, and treatment outcome was better in the early-group. However, successful correction was also present in the late-group, showing that the patients who have passed the optimum correction period should proceed after counselling.

Effects of Particulate Matter Exposure on the Eustachian Tube and Middle Ear Mucosa of Rats

OBJECTIVES

Particulate matter (PM) is a risk factor for various diseases. Recent studies have established an association between otitis media (OM) and PM exposure. To confirm this relationship, we developed a novel exposure model designed to control the concentration of PM, and we observed the effects of PM exposure on the Eustachian tube (ET) and middle ear mucosa of rats.

METHODS

Forty healthy, 10-week-old, male Sprague-Dawley rats were divided into 3-day, 7-day, 14-day exposure, and control groups (each, n=10). The rats were exposed to incense smoke as the PM source for 3 hours per day. After exposure, bilateral ETs and mastoid bullae were harvested, and histopathological findings were compared using microscopy and transmission electron microscopy (TEM). The expression levels of interleukin (IL)-1β, IL-6, tumor necrosis factor-α, and vascular endothelial growth factor (VEGF) in the middle ear mucosa of each group were compared using real-time reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

In the ET mucosa of the exposure group, the goblet cell count significantly increased after PM exposure (P=0.032). In the middle ear mucosa, subepithelial space thickening, increased angio-capillary tissue, and inflammatory cell infiltration were observed. Moreover, the thickness of the middle ear mucosa in the exposure groups increased compared to the control group (P<0.01). The TEM findings showed PM particles on the surface of the ET and middle ear mucosa, and RT-PCR revealed that messenger RNA (mRNA) expression of IL-1β significantly increased in the 3-day and 7-day exposure groups compared to the control group (P=0.035). VEGF expression significantly increased in the 7-day exposure group compared to the control and 3-day exposure groups (P<0.01).

CONCLUSION

The ET and middle ear mucosa of rats showed histopathologic changes after acute exposure to PM that directly reached the ET and middle ear mucosa. Therefore, acute exposure to PM may play a role in the development of OM.

Differences in the metabolomic profile of the human palatine tonsil between pediatrics and adults

Palatine tonsils (PT) are B cell-predominant lymphoid organs that provide primary immune responses to airborne and dietary pathogens. Numerous histopathological and immunological studies have been conducted on PT, yet no investigations have been conducted on its metabolic profile. We performed high-resolution magic angle spinning nuclear magnetic resonance spectroscopy-based metabolic profiling in 35 pediatric and 28 adult human palatine tonsillar tissue samples. A total of 36 metabolites were identified, and the levels of 10 metabolites were significantly different depending on age. Among them, partial correlation analysis shows that glucose levels increased with age, whereas glycine, phosphocholine, phosphoethanolamine, and ascorbate levels decreased with age. We confirmed the decrease in immunometabolic activity in adults through metabolomic analysis, which had been anticipated from previous histological and immunological studies on the PT. These results improve our understanding of metabolic changes in the PT with aging and serve as a basis for future tonsil-related metabolomic studies.

Outcomes of Endoscopic Congenital Cholesteatoma Removal in South Korea

Importance

Transcanal endoscopic ear surgery (TEES) provides minimally invasive transcanal access to the middle ear and improves middle ear visibility during cholesteatoma resection. However, the literature on outcomes following TEES alone for the removal of congenital cholesteatoma (CC) is lacking and limited to small series.

Objective

To assess outcomes of TEES for CC limited to the middle ear and/or mastoid antrum and to explore the risk factors associated with recidivism (ie, recurrent and/or residual cholesteatoma).

Design, Setting, and Participants

This cohort study evaluated retrospective, multicenter data for 271 children with CC who underwent TEES at 9 tertiary referral hospitals in South Korea between January 1, 2013, and December 31, 2021, and had a follow-up of at least 6 months after surgery.

Main Outcomes and Measures

Outcomes included the incidence of residual cholesteatoma and audiometric data after TEES. A multivariable analysis using Cox proportional hazards regression models was used to assess associations between cholesteatoma characteristics and recidivism, with hazard ratios (HRs) and 95% CIs reported.

Results

Of the 271 patients (mean [SD] age, 3.5 [2.9] years; 194 [71.6%] boys, 77 [28.4%] girls), 190 had Potsic stage I CC (70.1%), 21 (7.7%) had stage II, 57 (21.0%) had stage III, and 3 (1.1%) had stage IV. Thirty-six patients (13.3%) with residual cholesteatoma were found, including 15 (7.9%) with Potsic stage I, 3 (14.3%) with stage II, and 18 (31.6%) with stage III. In the multivariable analysis, invasion of the malleus (HR, 2.257; 95% CI, 1.074-4.743) and posterosuperior quadrant location (HR, 3.078; 95% CI, 1.540-6.151) were associated with the incidence of recidivism. Overall, hearing loss (>25 dB on auditory behavioral test or >30 dB of auditory evoked responses) decreased from 24.4% to 17.7% after TEES.

Conclusions and Relevance

This cohort study involved the largest known population to date of CC removed by TEES. The findings suggest that TEES may be feasible and effective for the removal of CC limited to the middle ear and/or mastoid antrum in children.

Outcomes of endoscopic tympanoplasty for large perforations: a multicenter retrospective study in South Korea

Objectives

Endoscopic tympanoplasty (ET) provides minimally invasive transcanal access to the middle ear and improves middle ear visibility for the treatment of tympanic membrane (TM) perforation. However, literature on surgical outcomes for large TM perforations is lacking and limited to small series. This study aimed to evaluate the clinical benefits of ET for large TM perforations.

Methods

This retrospective cohort study was conducted in nine tertiary referral hospitals in South Korea where 252 patients who underwent ET as a primary surgery from September 2019 to August 2021 were included. Outcome measures included graft success rate and pre- and postoperative audiometric data.

Results

Of 239 patients, graft success rate of ET for large or subtotal perforations was 86.2% (206 patients), while graft failure rate was 13.8% (33 patients). The graft failure rate directly correlated with the use of surgical techniques, including overlay and medial and lateral underlay tympanoplasty (P=0.027). Sex, laterality, etiology, site and size of perforation, operation time, and graft materials did not vary significantly between the graft success and failure groups (P > 0.05). The mean air-bone gap improved significantly (graft success group; 10.0 ± 0.6 dB and graft failure group; 7.7 ± 0.3 dB, P < 0.001) in both groups. However, ABG improvement did not significantly differ between the groups. Analysis of covariance (ANCOVA) revealed that postoperative 500Hz bone conduction threshold was improved after successful ET (adjusted coefficient, -11.351; 95% CI, -21.491,-1.212; P=0.028).

Conclusion

This study involved the largest population to date, of large TM perforations treated by ET. The study findings suggest that ET is feasible and effective in treating large TM perforations.

The Optimized Protocol of Hyperbaric Oxygen Therapy For Sudden Sensorineural Hearing Loss

OBJECTIVE

This study aimed to determine the optimal protocol of hyperbaric oxygen therapy (HBOT) according to various treatment settings for sudden sensorineural hearing loss (SSNHL).

METHODS

A 112 patients with SSNHL were enrolled in this prospective study. All patients were treated with systemic steroid therapy, intratympanic steroid therapy, and HBOT. According to the pressure and duration of HBOT (10 sessions in total), the patients were divided into three groups: group 1, 2.5 atmospheres absolute (ATA) for 1 h; group 2, 2.5 ATA for 2 h; and group 3, 1.5 ATA for 1 h. The pure-tone average (PTA), word discrimination score (WDS), and mean gain were compared.

RESULTS

A total of 105 patients completed the 3-month follow-up, and 6 patients were excluded. Differences among groups were found in PTA, WDS, and mean gain. In the post-hoc analysis, group 3 had significantly lower WDS and mean gain than groups 1 and 2; however, group 2 showed no significant differences from group 1. The proportion of patients with hearing recovery after treatment was significantly higher in group 1 (57.6%) and group 2 (58.8%) than in group 3 (31.3%).

CONCLUSIONS

When HBOT (10 sessions) was combined with corticosteroids as the initial therapy for SSNHL, a higher pressure (1.5 ATA vs. 2.5 ATA) provided better treatment results; however, increasing the duration (1 h vs. 2 h) under 2.5 ATA did not result in a significant difference. Therefore, HBOT for SSNHL may be performed at 2.5 ATA for 1 h in 10 sessions. Laryngoscope, 133:383-388, 2023.

Auricular Reconstruction for Bilateral Auricular Deformity Caused by Relapsing Polychondritis

This case report describes a woman in her early 20s who presented to the hospital with an acquired auricular deformity after an ear piercing and was diagnosed with recurrent polychondritis that required total auricular reconstruction.

Clinical features and prognosis of severe-to-profound sudden sensorineural hearing loss

PURPOSE

Sudden sensorineural hearing loss (SSNHL) is an otologic emergency. Despite multiple efforts to clarify the factors affecting the prognosis of severe-to-profound SSNHL, various studies showed inconsistent results and lack of clinical significance. Therefore, we examined the clinical features and outcomes of severe-to-profound SSNHL.

MATERIALS AND METHODS

We included patients who experienced SSNHL between 2018 and 2021 and were diagnosed according to the American Academy of Otolaryngology-Head and Neck Surgery criteria; hearing loss over 70 dB on initial pure tone audiometry (PTA) was used to define severe-to-profound SSNHL. We retrospectively examine the demographic, laboratory, radiologic, and audiometric data of SSNHL patients. We also evaluated the final hearing gain of these patients by assessing their PTA findings and word-recognition scores.

RESULTS

Of the 178 patients, 94 (52.81%) and 84 (47.19%) showed profound (>90 dB) and severe (>70 to 90 dB) hearing loss, respectively. The presence of vertigo and hypertension differed significantly between the severe and profound groups (p < 0.001 and p = 0.012, respectively), as did the initial serum creatinine level (p = 0.043). Recovery in PTA showed a reliable correlation with the interval between onset and treatment in the severe group and periventricular white-matter findings in the profound group (p < 0.001 and p = 0.011, respectively). The presence of hypertension was related to recovery of low tone (p = 0.023 for 250 Hz; p = 0.034 for 500 Hz), while glycated hemoglobin level was related to recovery of high tone in the severe group (p = 0.049 for 4000 Hz; p = 0.047 for 8000 Hz).

CONCLUSIONS

Severe-to-profound SSNHL showed poor prognosis for hearing gain. The interval from onset to treatment was a significant prognostic factor for severe SSNHL, while the presence of vertigo, estimated glomerular filtration rate, and periventricular white-matter findings were significant prognostic factors for profound SSNHL.

Device failure caused by the dissociation of floating mass transducer in Vibrant SoundBridge®

BACKGROUND

Vibrant SoundBridge® (VSB), a semi-implantable middle ear device, is one of the treatment options for patients with mild-to-severe sensorineural hearing loss or mixed hearing loss. Herein, we report delayed device failure after VSB surgery in two patients.

CASE PRESENTATION

In both cases, a revision surgery was performed for the removal of the device; dissociation of the floating mass transducer (FMT) and coupler was noticed in one patient, and dissociation of the FMT-coupler complex from the short process of the incus in the other. In Case 1, the vibration-like sounds disappeared after the surgery. In Case 2, wearing bilateral hearing aids improved hearing after removal surgery, but complaints regarding speech discrimination persisted. Both cases show the importance of not loosening the connectivity between the FMT, coupler, and short process of the incus during VSB surgery.

CONCLUSIONS

To our knowledge, there has been no report of dissociation from the short process of the incus or the dissociation between an FMT and the coupler.

A multicenter, randomized, active-controlled, clinical trial study to evaluate the efficacy and safety of navigation guided balloon Eustachian tuboplasty

To assess the safety and efficacy of navigation-guided balloon Eustachian tuboplasty (BET) compared to medical management (MM) alone in patients with chronic Eustachian tube dilatory dysfunction (ETD). This is a prospective, multicenter, 1:1 parallel-group, randomized controlled trial (RCT). It aims to assess the efficacy of navigation-guided BET compared to MM alone in patients with chronic ETD. The primary outcome measure was an improvement in the Eustachian tube dysfunction questionnaire (ETDQ)-7 score at the 6-week follow-up compared with baseline. Secondary outcome measures included changes in the signs and symptoms during the follow-up, changes in the score for each subcategory of ETDQ-7, type of tympanometry, pure tone audiometry, and the availability of a positive modified Valsalva maneuver. Navigation-guided BET was safely performed in all patients. A total of 38 ears of 31 patients (19 ears of 16 patients in the BET group and 19 ears of 15 patients in the control group) completed the planned treatment and 6 weeks of follow-up. More patients in the BET group (1.99 ± 0.85) had less symptomatic dysfunction than in the control group (3.40 ± 1.29) at 6 weeks post-procedure (P = 0.001). More patients experienced tympanogram improvement in the BET group at 6 weeks compared to the control group (36.5% vs. 15.8%) with a positive modified Valsalva maneuver (36.6% vs. 15.8%, P = 0.014). Additionally, air–bone gap change was significantly decreased in the BET group compared to the control group at the 6-week follow-up visit (P = 0.037). This prospective, multicenter, RCT study suggests that navigation-guided BET is a safe and superior treatment option compared to MM alone in patients with chronic ETD.

Effects of cigarette smoke on Haemophilus influenzae-induced otitis media in a rat model

Exposure to cigarette smoke (CS) is a factor that could delay or worsen the recovery of otitis media (OM) by causing inflammatory swelling of the Eustachian tube (ET). However, despite the suggested relationship, little is known about the association between OM and CS. Therefore, we aimed to evaluate the effects of CS on the development, progression, and recovery of OM, as well as the histological and molecular changes caused by CS exposure, by using a rat model of OM infected with non-typeable Haemophilus influenzae (NTHi). Eighty Sprague-Dawley rats with normal middle ears (MEs) were divided into four groups (n = 20 rats/group): control, CS, OM, and CS + OM. The CS and CS + OM groups were exposed to CS for 2 weeks. The inflammatory reaction to NTHi was more intense and lasted longer in the CS + OM group than in the other groups. Goblet cell proliferation and mucus secretion in the ET were more significant in the CS and CS + OM groups than in the other groups. These findings suggested that because CS directly affects the ET and ME mucosa, bacterial OM can become more severe and may resolve more slowly in the presence of CS exposure rather than in its absence.

Comparison of Medial Underlay and Lateral Underlay Endoscopic Type I Tympanoplasty for Anterior Perforations of the Tympanic Membrane

OBJECTIVES

To compare the outcomes of medial and lateral underlay endoscopic type I tympanoplasty for anterior tympanic membrane (TM) perforations.

STUDY DESIGN

Retrospective chart review.

SETTING

Tertiary care academic referral center.

PATIENTS

Patients who were diagnosed with either chronic otitis media with dry and stable anterior TM perforations or traumatic anterior TM perforations and underwent endoscopic type I tympanoplasty between 2017 and 2019.

INTERVENTIONS

Medial or lateral underlay type I endoscopic tympanoplasty.

MAIN OUTCOME MEASURES

Patient demographics, size, and location of TM perforation, graft success rate, and hearing outcome.

RESULTS

Of the 170 patients, 68 and 102 patients underwent the medial and lateral underlay techniques, respectively. Patient demographics were not significantly different between groups, except the middle ear mucosa status. Graft success rates were significantly different between groups regardless of the perforation size (85.3 and 95.1%, p < 0.001). The lateral underlay group had a significantly better outcome (p < 0.001) when anterior superior quadrant TM perforation was included than the medial underlay group (p = 0.552). Hearing outcomes did not significantly differ between groups, but a significant audiological improvement was observed in both groups (p < 0.05).

CONCLUSION

Lateral underlay type I endoscopic tympanoplasty can be challenging as it requires dissection of the malleus. However, the lateral underlay group had a high graft success rate without sensorineural hearing loss in the repair of anterior TM perforations. Thus, lateral underlay type I endoscopic tympanoplasty should be considered for repairing anterior TM perforations, especially when the anterior superior quadrant is involved.

The Clinical Value of Periventricular White Matter Hyperintensity on MRI in Sudden Sensorineural Hearing Loss

OBJECTIVES

To assess the clinical value of periventricular white matter hyperintensity (PWMH) found on brain magnetic resonance imaging (MRI) in patients with sudden sensorineural hearing loss (SSNHL).

METHODS

In this prospective study, 115 patients who were diagnosed with SSNHL aged between 55 and 75 years were analyzed. All subjects underwent brain MRI and were divided into a PWMH and control groups, depending on the presence of PWMH on MRI. PWMH was subdivided into 3 groups according to severity. Pure-tone average results and hearing gain were compared between the 2 groups before treatment and 2 months after treatment. Hearing improvement was assessed using Sigel's criteria.

RESULTS

A total of 106 patients (43 in the PWMH group and 63 in the control group) finally completed the 2-month follow-up. Average hearing gain in the PWMH group was significantly higher than in the control group (34.8 ± 20.3 and 25.9 ± 20.3, respectively, P = .029). PWMH score 1 showed significantly better hearing levels and hearing gain compared to PWMH score 3 and the control group. Multivariate analysis revealed that younger age, better initial hearing level, and the presence of PVWM score 1 were associated with good recovery.

CONCLUSIONS

The presence of PWMH score 1 on brain MRI in patients with SSNHL was associated with better treatment response and was a good prognostic factor in a multivariate analysis while the hearing recovery in more severe PWMH (scores 2, 3) was not different from the control group.

A longitudinal study of changes of congenital auricular deformity regarding self-correction

This study aimed to investigate the factors associated with congenital auricular deformities and evaluate the long-term frequency of their self-correction. Ninety newborns were enrolled in the study, and data were collected within 2 weeks after birth and at 1 year. The shape of the auricle was classified into seven categories using a digital image. At 2 weeks after birth, several birth-related factors were evaluated in the auricular deformity and normal groups. At 1 year after birth, the images of auricles were compared with the images at birth, and the changes in the auricle shape were investigated. Congenital auricular deformities were observed in 139 out of 180 ears, and the major type noted was helix rim deformity (47 ears), followed by normal ears (41 ears), and cup ears (33 ears). Male sex was found to have a statistically significant association with the occurrence of auricular deformity. In the longitudinal study, among 43 neonates (86 ears) followed-up 12 months later, the self-correction rate was approximately 50%. The normal auricle and prominent ear increased, helix rim deformity and cup ear decreased significantly. The prognosis of deformity varied depending on the type of deformity. Considering the low self-correction rate in the prominent and cup ears, newborns with these deformities might be recommended to undergo management such as auricle molding technique, as required.

Mammalian Cochlear Hair Cell Imaging Using Optical Coherence Tomography (OCT): A Preliminary Study

OBJECTIVES

This study aimed to investigate the feasibility of using optical coherence tomography (OCT) to provide information about cochlear microanatomy at a cellular level, specifically of cochlear hair cells in mammals.

MATERIALS AND METHODS

A total of 10 Sprague-Dawley rats were divided into 2 experimental groups for comparing the arrangement of normal and damaged hair cells. Postnatal day 3 Sprague-Dawley rats were used to test the swept-source OCT system, and the images recorded were compared with fluorescence microscope images.

RESULTS

Intracochlear structures (the inner hair cells, outer hair cells, and auditory nerve fibers) were clearly visualized at the individual cellular level.

CONCLUSION

These images reflect the ability of OCT to provide images of the inner hair cells, outer hair cells, and auditory nerve fibers (ex vivo). OCT is a promising technology, and these findings could be used to encourage research in the area of cochlear microstructure imaging in the future.

Comparative study of endoscopic and microscopic tympanoplasty performed by a single experienced surgeon

PURPOSE

The use of endoscopes in otologic procedures has been increasing worldwide. This study aimed to compare the efficacy of microscopic tympanoplasty (MT) and endoscopic tympanoplasty (ET) for tympanic membrane and middle ear surgery.

MATERIALS AND METHODS

We retrospectively analyzed 81 patients who underwent MT (n = 44) and ET (n = 37) for chronic otitis media with tympanic membrane perforation performed by a single surgeon between January 2013 and September 2019. The hearing outcomes, graft success rate, complications, operation time and hospital stay, and cost-effectiveness were recorded and compared between groups. Hearing outcomes were determined by pure tone audiometry. Cost-effectiveness was determined by the operation cost and total cost.

RESULTS

There was no significant difference between the MT and ET groups regarding demographic characteristics, with the exception of the male:female ratio. There was no significant difference in the pre- and postoperative air conduction, bone conduction thresholds, and air-bone gap values between the two groups, but a significant audiologic improvement was observed in both groups (p < 0.05). In terms of recurrence of tympanic membrane perforation, postoperative otorrhea, and discomfort symptoms, there was no significant difference between groups (p > 0.05). The operation time and hospital stay were shorter in the ET group than in the MT group (p < 0.05). There were no significant differences in operation cost between the two groups (p > 0.05), but the total cost was significantly lower in the ET group than the MT group (p < 0.05).

CONCLUSION

ET is as safe and medically efficacious as conventional MT, shortens the operation time and hospital stay, and is cost-effective.

The usefulness of Valsalva computed tomography as an assessment tool for the Eustachian tube

PURPOSE

To determine the usefulness of 'computed tomography (CT) with Valsalva maneuver (VM)' (Valsalva CT) for localizing lesions of the eustachian tube (ET) and identifying characteristics of ET dysfunction (ETD).

MATERIALS AND METHODS

In this case-control study, 12, 17, and 25 patients with obstructive ETD (OETD), patulous eustachian tube (PET), and conductive hearing loss (control), respectively, underwent Valsalva CT in the supine position. The visualized length to total length ratio of the cartilaginous ET (VTRET) with and without VM were compared in the three groups. In the OETD group, obstructed areas of the ET were identified on multiplanar reconstructed images.

RESULTS

VTRET without VM in the PET group was significantly higher than that in the control and OETD groups (p-values, 0.003 and 0.007, respectively). However, there was no significant difference between the control and OETD groups (p = 0.053). VTRET with VM in the PET group was significantly higher than that in the other two groups (p < 0.001), whereas that in the control group was significantly higher than that in the OETD group (p < 0.001). In the OETD group, the obstructed area was clearly identified, and there were one, one, six, and eight patients in the isthmus; bony portion and isthmus; bony portion, isthmus, and cartilaginous portion; and isthmus and cartilaginous portion subgroups, respectively.

CONCLUSION

Valsalva CT is particularly valuable as a visualization assessment tool for identifying obstructed areas in the OETD. It may help future research of disease-specific mechanical characteristics of the ET on controlling pressure variables.

Navigation-Assisted Balloon Eustachian Tuboplasty for Eustachian Tube Dilatory Dysfunction

Objectives.

Balloon Eustachian tuboplasty (BET) is a novel treatment method for Eustachian tube dilatory dysfunction (ETD). However, surgeons cannot identify the insertion depth of the catheter during BET, resulting in potential risks such as internal carotid artery (ICA) injury. Therefore, we developed an image-guided navigation balloon catheter to identify the insertion depth of the catheter and to establish awareness of the proximity of the ICA. This study aimed to evaluate the technical feasibility of this image-guided navigation balloon catheter system in patients with ETD.

Methods.

Twenty-nine patients (38 ears; nine bilateral; 21 right ears, and 17 left ears) diagnosed with ETD were assessed. All patients who showed no improvement despite medical therapy with topical steroids, anti-reflux medication, and the Valsalva maneuver for a minimum of 6 weeks received image-guided navigation-assisted BET. The 7-item Eustachian Tube Dysfunction Questionnaire (ETDQ-7) score and Valsalva maneuver were used to evaluate patients’ symptoms preoperatively and at the postoperative follow-up.

Results.

Image-guided navigation-assisted BET was safely performed in all patients. The mean total ETDQ-7 score was 25.4±7.1 preoperatively, 17.5±6.2 at 1 month, and 15.2±7.0 at 6 months (P<0.001). In total, a Valsalva maneuver was possible for 28 of 38 ears (73.7%) at the time of the patient’s final visit at 6 months post-procedure.

Conclusion.

Image-guided navigation balloon catheters are a potentially valuable tool in patients with ETD. Their use is also technically feasible and safe when performing BET to treat ETD.

Clinicoradiologic Characteristics of Temporal Bone Meningioma: Multicenter Retrospective Analysis

OBJECTIVES/HYPOTHESIS

Meningioma is a neoplasm arising from cells related to the arachnoid villi. The aim of the present study was to explore the clinical and radiological characteristics of temporal bone meningioma (TBM) in a multicenter cohort.

STUDY DESIGN

Retrospective cohort study.

METHODS

Thirteen patients diagnosed with TBM at eight medical institutes between 1998 and 2018 were retrospectively enrolled. The clinical procedures, symptoms, signs, and images that led to the diagnosis of TBM were investigated for all patients.

RESULTS

The most common symptom at the initial visit was hearing loss (n = 12/13, 92.3%). All patients exhibited unilateral TBMs with varied symptom durations (1-60 months). Four patients presented masses occupying the external auditory canal; the tympanic membrane (TM) could not be evaluated. The other nine patients did not show TM perforation despite the presence of inflammatory signs. The majority of patients exhibited unilateral conductive or mixed hearing loss. A retrospective review of temporal bone computed tomography (TBCT) images revealed findings suggestive of a tumor in all patients. However, three patients had been misdiagnosed with chronic otitis media and were subjected to tympanomastoidectomy (n = 3/7, 42.9%). TBCT findings that suggested TBM included diffuse trabecular hyperostosis in the middle and posterior cranial fossae and widening and destruction of the temporal bone in the jugular bulb area.

CONCLUSIONS

TBM should be suspected if patients exhibit persistent inflammatory symptoms or signs involving intact TM or unilateral conductive or mixed hearing loss with trabecular hyperostosis or destruction of the temporal bone on computed tomography images.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:173-178, 2021.

Extratympanic Observation of Middle and Inner Ear Structures in Rodents Using Optical Coherence Tomography

Objectives

This study aimed to investigate whether optical coherence tomography (OCT) provides useful information about the microstructures of the middle and inner ear via extratympanic approach and thereby could be utilized as an alternative diagnostic technology in ear imaging.

Methods

Five rats and mice were included, and the swept-source OCT system was applied to confirm the extent of visibility of the middle and inner ear and measure the length or thickness of the microstructures in the ear. The cochlea was subsequently dissected following OCT and histologically evaluated to compare with the OCT images.

Results

The middle ear microstructures such as ossicles, stapedial artery and oval window through the tympanic membrane with the OCT could be confirmed in both rats and mice. It was also possible to obtain the inner ear images such as each compartment of the cochlea in the mice, but the bone covering bulla needed to be removed to visualize the inner ear structures in the rats which had thicker bulla. The bony thickness covering the cochlea could be measured, which showed no significant differences between OCT and histologic image at all turns of cochlea.

Conclusion

OCT has been shown a promising technology to assess real-time middle and inner ear microstructures noninvasively with a high-resolution in the animal model. Therefore, OCT could be utilized to provide additional diagnostic information about the diseases of the middle and inner ear.

Acellular Dermal Matrix Mistaken as Recurrence of Malignancy Following Surgery on Positron Emission Tomography/Computed Tomography: A Case Report

OBJECTIVES

To report a rare clinical presentation of an acellular dermal matrix (ADM) used during lateral temporal bone resection mimicking recurrence of cancer of external auditory canal (EAC) on positron emission tomography/computed tomography (PET/CT) 9 months after surgery.

METHODS

Case report and literature review.

RESULTS

A 71-year-old woman underwent lateral temporal bone resection 9 months earlier for management of squamous cell carcinoma of the EAC. She exhibited recurrence of the tumor on ¹⁸F-FDG PET/CT with an intense uptake value (SUV_max 12.8) at the operated site. Exploration was conducted as the location of the lesion was unfavorable to perform biopsy. However, histopathologic evaluation revealed that the lesion was the ADM implanted during surgery.

CONCLUSIONS

Care should be taken when using an ADM during malignant tumor surgery if the site of surgery is not conducive for fine needle aspiration or biopsy.

Management of Acquired Cholesteatoma Associated With Patulous Eustachian Tube and Habitual Sniffing

OBJECTIVES

To investigate the effect of surgical treatment with eustachian tube (ET) catheter insertion in patients with acquired cholesteatoma associated with patulous eustachian tube (PET) and habitual sniffing.

METHODS

Nine ears of nine patients (two men and seven women; age, 20 to 65 years; average, 37.9±12.0 years) of acquired cholesteatoma associated with PET and habitual sniffing who underwent cholesteatoma surgery with simultaneous additional ET catheter insertion were examined in this study. Successful treatment was defined as stoppage of sniffing, a relief of a PET handicap inventory-10 (PHI-10), an improvement of autophony grade and no cholesteatoma recurrence.

RESULTS

ET catheter insertion was performed in all ears. Follow-up duration ranged from 16 to 37 months (average, 25.4 months). Cases consisted of nine pars flaccida type (100%). All patients obtained relief from aural symptoms and stopped sniffing. Postoperative PHI-10 scores were significantly lower than preoperative scores (P<0.001). During an average follow-up of 25.4 months, no cholesteatoma recurrence has occurred to date. One patient developed otitis media with effusion (OME) post-catheterization; OME resolved spontaneously without treatment. Four patients had a consecutive ET catheter insertion on the other side to resolve PET-related aural symptoms.

CONCLUSION

In case of acquired cholesteatoma with PET and habitual sniffing, ET catheter insertion performed simultaneously with cholesteatoma surgery could help reduce aural symptoms and stop sniffing. Moreover, the procedure might help in preventing cholesteatoma recurrence.

Comparison of Two Different Treatment Protocols Using Systemic and Intratympanic Steroids with and without Hyperbaric Oxygen Therapy in Patients with Severe to Profound Idiopathic Sudden Sensorineural Hearing Loss: A Randomized Controlled Trial

Objectives: This study aimed to investigate the efficacy of simultaneous steroid and hyperbaric oxygen therapy (HBOT) in patients with severe to profound idiopathic sudden sensorineural hearing loss (ISSNHL), which has a poor prognosis. Methods: Sixty patients diagnosed with severe to profound ISSNHL (≥70 dB HL) were randomly divided into two groups in a prospective controlled trial: an oral steroid + intratympanic steroid injection (ITSI) group (control group) and an oral steroid + ITSI + HBOT group (study group). Pure-tone audiometry (PTA) results and word discrimination scores (WDS) were compared between the two groups before treatment and 10 days and 1, 2, and 3 months after treatment. Hearing improvement was assessed using the modified American Academy of Otolaryngology-Head and Neck Surgery criteria. Analyses were by both intention to treat and per protocol. Results: A total of 58 patients completed the 3-month follow-up, and 2 patients in the study group were excluded due to follow-up loss in the per-protocol analysis. In the intention-to-treat and per-protocol analyses, the study group showed significantly better hearing levels than did the control group at 500 Hz (p < 0.05) 1 month after treatment and at 1 kHz (p < 0.05) 3 months after treatment. However, the average PTA values and PTA at 2, 4, and 8 kHz showed no significant difference. WDS improvement was significantly higher in the study group compared to the control group 3 months after treatment by both per-protocol (66.4 ± 13.3 and 56.7 ± 19.1%, respectively; p = 0.029) and intention-to-treat analyses (65.9 ± 14.1 and 56.7 ± 19.1%, respectively; p = 0.035). The sum of complete and partial hearing recovery for the study group was significantly higher than that for the control group by per-protocol analysis (60.7 vs. 33.3%; p = 0.037) and intention-to-treat analysis (60.0 vs. 33.3%; p = 0.038). Conclusion: These results demonstrate that the addition of HBOT to steroid combination therapy does not improve the average PTA values in severe to profound ISSNHL; however, it was associated with a better outcome at 500 Hz 1 month after treatment and, at 1 kHz, WDS 3 months after treatment. The sum of complete and partial hearing recovery was significantly higher for the study group than for the control group.

Application of endoscopy in otology: Changes over the last 8years in Korean Otological Society

OBJECTIVES

Despite the worldwide availability of endoscope in otology, it still has not replaced the microscopic surgery as it has for nose surgery. In 2008, we administered a questionnaire on the preference of using otoscopes in Korea. In light of the worldwide availability of endoscopic ear surgery, we have now conducted a more detailed survey to determine if this preference has changed over 8years.

SUBJECTS AND METHODS

A questionnaire consisting of 10 questions was used to survey members of the Korean Otological Society who were actively performing middle ear surgery. The responses to this questionnaire were compared to those from 2008. The study also determined the preference for endoscope use based on the surgeon's experience.

RESULTS

The mean surgical experience of the otologists was 12.7years. Endoscopy for tympanoplasty and tympanomastoidectomy increased over a period of 8years. In the outpatient clinic, the use of endoscopy also increased; over 8-year period, it surpassed the microscope as the most preferred diagnostic tool in the outpatient clinic. Greater than half of the operating rooms were equipped with endoscopic sets; however, only 4.5% of otologists acknowledged having endoscopic instruments.

CONCLUSION

Endoscopy for surgery and in outpatient clinic assessment increased in otology in Korea; however, endoscopes have consistently been used as an adjuvant to the microscope to improve visualization of the tympanic cavity rather than as a tool for totally endoscopic ear surgery.

Multiple Dural Arteriovenous Fistulas Presenting as Pulsatile Tinnitus Treated with External Manual Compression

Dural arteriovenous fistula (DAVF) have been treated by transarterial or transvenous embolization, surgery, and radiosurgery. Besides these treatment options, the external compression technique is a non-invasive, low-cost form of treatment. This article reports that a 60-year-old man with DAVF between multiple arterial branches and transverse/sigmoid sinus was treated by repeated external manual compression method.

Clinical and audiological characteristics of 1000Hz audiometric notch patients

PURPOSE

Among the hearing loss patients, we can confirm that the hearing loss of the specific frequency decreases, such as the 2000Hz notch in otosclerosis and the 4000Hz notch (c5-dip) in noise-induced hearing loss. The 1000Hz notch (c3-dip), however, is rarely studied. We fortuitously encountered a group of patients with a 1kHz hearing loss and report it with a review of the literature.

METHODS

Otological history, audiogram, diagnosis, occupation, and history of noise exposure were reviewed from charts and telephone interview, and compared between c3-dip and c5-dip patients (n=98).

RESULTS

Thirty-one patients (mean age: 46.2years) demonstrated 1kHz hearing loss; these included 11 males. The pure-tone threshold was 37.97dB at 1kHz and the average threshold was 22.38dB at other frequencies. In the c3-dip group, tinnitus was the most common complaint, while sudden sensorineural hearing loss and idiopathic tinnitus (n=8 each) were the most common diagnoses. Female patients and unilateral cases were more common in the c3-dip than in the c5-dip group, and ear fullness was more common in the c3-dip group than in the c5-dip group. The duration of occupation-related noise exposure was longer in the c5 group, and head or ear trauma was more frequent in the c3-dip group.

CONCLUSION

We have defined a new clinical entity of 1kHz hearing loss in patients, defined as the c3-dip, which was clinically and audiologically distinct from the c5-dip. Further study is needed to clarify this new entity of hearing loss.

Sample-to-answer on molecular diagnosis of bacterial infection using integrated lab--on--a--disc

Sepsis by bacterial infection causes high mortality in patients in intensive care unit (ICU). Rapid identification of bacterial infection is essential to ensure early appropriate administration of antibiotics to save lives of patients, yet the present benchtop molecular diagnosis is time-consuming and labor-intensive, which limits the treatment efficiency especially when the number of samples to be tested is extensive. Therefore, we hereby report a microfluidic platform lab-on-a-disc (LOAD) to provide a sample-to-answer solution. Our LOAD customized design of microfluidic channels allows automation to mimic sequential analytical steps in benchtop environment. It relies on a simple but controllable centrifugation force for the actuation of samples and reagents. Our LOAD system performs three major functions, namely DNA extraction, isothermal DNA amplification and real-time signal detection, in a predefined sequence. The disc is self-contained for conducting sample heating with chemical lysis buffer and silica microbeads are employed for DNA extraction from clinical specimens. Molecular diagnosis of specific target bacteria DNA sequences is then performed using a real-time loop-mediated isothermal amplification (RT-LAMP) with SYTO-9 as the signal reporter. Our LOAD system capable of bacterial identification of Mycobacterium tuberculosis (TB) and Acinetobacter baumanii (Ab) with the detection limits 103cfu/mL TB in sputum and 102cfu/mL Ab in blood within 2h after sample loading. The reported LOAD based on an integrated approach should address the growing needs for rapid point-of-care medical diagnosis in ICU.

Endoscopic autologous cartilage injection for the patulous eustachian tube

Patulous eustachian tube (PET) can have a significant negative impact on a patient's quality of life. Several methods of surgical management can be an option to treat PET, and our objective is to evaluate the safety and efficacy of autologous cartilage injection in patients with PET. Thirty-three ears of twenty-five patients with chronic PET refractory to conservative treatment were enrolled to this study. Autologous tragal cartilage was harvested, and chopped into fine pieces to allow its injection using a 1 cc Bruening syringe. Endoscopic cartilage injection was performed submucosally into the anterior (0.5 mL) and posterior aspects (0.5 mL) of the nasopharyngeal ET under local anesthesia in an operating room. Patients were evaluated postoperatively by nasal endoscopy and by interview to document symptoms. Successful treatment was defined as complete relief or significant improvement plus satisfaction with treatment. The only complication that occurred was temporary otitis media with effusion in one ear. Inferior turbinate reduction was performed in three ears with accompanying nasal septal deviation or turbinate hypertrophy to allow better nasopharyngeal ET visualization. After autologous cartilage injection, the successful treatment rate, as determined by subjective autophony symptoms, was 69.7% (23/33). The average follow-up period was 25.2 months. Autologous cartilage injection is a minimally invasive technique that has been used by the authors to successfully treat patulous eustachian tube. The described procedure was found to provide a good overall success rate without long-term complications.

Dysregulated Serum MiRNA Profile and Promising Biomarkers in Dengue-infected Patients

OBJECTIVES

Pathological biomarkers and mechanisms of dengue infection are poorly understood. We investigated a new serum biomarker using miRNAs and performed further correlation analysis in dengue-infected patients.

METHODS

Expression levels of broad-spectrum miRNAs in serum samples from three patients with dengue virus type 1 (DENV-1) and three healthy volunteers were separately analyzed using miRNA PCR arrays. The expressions of the five selected miRNAs were verified by qRT-PCR in the sera of 40 DENV-1 patients and compared with those from 32 healthy controls. Receiver operating characteristic (ROC) curve and correlation analyses were performed to evaluate the potential of these miRNAs for the diagnosis of dengue infection.

RESULTS

MiRNA PCR arrays revealed that 41 miRNAs were upregulated, whereas 12 miRNAs were down-regulated in the sera of DENV-1 patients compared with those in healthy controls. Among these miRNAs, qRT-PCR validation showed that serum hsa-miR-21-5p, hsa-miR-590-5p, hsa-miR-188-5p, and hsa-miR-152-3p were upregulated, whereas hsa-miR-146a-5p was down-regulated in dengue-infected patients compared with healthy controls. ROC curves showed serum hsa-miR-21-5p and hsa-miR-146a-5p could distinguish dengue-infected patients with preferable sensitivity and specificity. Correlation analysis indicated that expression levels of serum hsa-miR-21-5p and hsa-miR-146a-5p were negative and positively correlated with the number of white blood cells and neutrophils, respectively. Functional analysis of target proteins of these miRNAs in silico indicated their involvement in inflammation and cell proliferation.

CONCLUSION

Dengue-infected patients have a broad "fingerprint" profile with dysregulated serum miRNAs. Among these miRNAs, serum hsa-miR-21-5p, hsa-miR-146a-5p, hsa-miR-590-5p, hsa-miR-188-5p, and hsa-miR-152-3p were identified as promising serum indicators for dengue infection.

Trans-tympanic catheter insertion for treatment of patulous eustachian tube

OBJECTIVES

To evaluate the safety and therapeutic efficacy of trans-tympanic catheter insertion (TCI) in patients with refractory patulous eustachian tube (PET).

METHODS

TCI was attempted in thirty-six ears of twenty-nine patients with chronic PET refractory to conservative treatment. The catheter was inserted under local anesthesia in an operating room through the bony orifice of the eustachian tube (ET) to occlude the isthmus of the tube via a myringotomy site on the tympanic membrane. Patients were evaluated postoperatively by nasal endoscopy and by interview to document symptoms. Successful treatment was defined as complete relief or significant improvement plus satisfaction with treatment. Patients had no concurrent disease and did not undergo any additional surgical procedure.

RESULTS

TCI was performed in all except one ear, in which it failed because of an abnormally narrow tympanic ET orifice. Follow-up durations ranged from 6 to 37 months, with an average of 19.3 months. Successful treatment of subjective autophony was achieved in twenty-nine (82.4%) of the thirty-five ears. Ventilation tube (VT) placement was performed in the two ears because of otitis media with effusion (OME) after TCI. In one ear, the inserted catheter was finally removed due to additional unilateral mastoiditis after VT extrusion.

CONCLUSION

TCI seems to be a minimally invasive and was used successfully to treat PET. The procedure had a good overall success rate and complications were rare in the long-term.

A non-PCR SPR platform using RNase H to detect MicroRNA 29a-3p from throat swabs of human subjects with influenza A virus H1N1 infection

As in all RNA viruses, influenza viruses change and mutate constantly because their RNA polymerase has no proofreading ability. This poses a serious threat to public health nowadays. In addition, traditional pathogen-based detection methods may not be able to report an infection from an unknown type or a subtype of virus if its nucleotide sequence is not known. Because of these factors, targeting host microRNA signatures may be an alternative to classify infections and distinguish types of pathogens as microRNAs are produced in humans shortly after infection. Although this approach is in its infant stage, there is an urgent need to develop a rapid reporter assay for microRNA for disease control and prevention. As a proof of concept, we report herein for the first time a non-PCR MARS (MicroRNA-RNase-SPR) assay to detect the microRNA miR-29a-3p from human subjects infected with influenza virus H1N1 by surface plasmon resonance (SPR). In our MARS assay, RNase H is employed to specifically hydrolyze the RNA probes immobilized on the gold surface where they hybridize with its cognate target cDNAs miR-29a-3p, where it was formed from reverse transcription with mature miR-29a-3p specific stem-looped primers. After the digestion of the RNA probe by RNase H, the intact cDNA was released from the RNA-DNA hybrid and bound to a new RNA probe for another enzymatic reaction cycle to amplify signals. With assay optimization, the detection limit of our MARS assay for miR-29a-3p was found to be 1 nM, and this new assay could be completed within 1 hour without thermal cycling. This non-PCR assay with high selectivity for mature microRNA provides a new platform for rapid disease diagnosis, quarantine and disease control.

Recurrent benign myoepithelioma of the auricle

Myoepithelioma, a generally benign tumor comprised of myoepithlial cells, is an uncommon salivary gland tumor. Myoepithelioma originates primarily in the parotid gland, but several isolated cases have been described. Although myoepithelioma has a benign nature, but there is a potential risk of malignant change and recurrence in case of incomplete resection. We acknowledge that benign myoepithelioma originating from the auricle has not been reported in the English literature. We present a rare case of 27-year-old female who had recurrent benign myoepithelioma originating from the auricle and already had been given twice operations at the other clinic.

Dysregulated Serum MicroRNA Expression Profile and Potential Biomarkers in Hepatitis C Virus-infected Patients

OBJECTIVES

Circulating microRNAs (miRNAs) play critical roles in pathogen-host interactions. Aberrant miRNA expression profiles might have specific characteristics for virus strains, and could serve as noninvasive biomarkers for screening and diagnosing infectious diseases. In this study, we aimed to find new potential miRNA biomarkers of hepatitis C virus (HCV) infection.

METHODS

Expression levels of broad-spectrum miRNAs in serum samples from 10 patients with HCV viremia and 10 healthy volunteers were analyzed using miRNA PCR arrays. Subsequently, the differential expression of four selected miRNAs (miR-122, miR-134, miR-424-3p, and miR-629-5p) was verified by qRT-PCR in the serum of 39 patients compared with that in 29 healthy controls. Receiver operating characteristic (ROC) curve analysis was performed to evaluate their potential for the diagnosis of HCV infection.

RESULTS

miRNA PCR array assays revealed differential expression of 106 miRNAs in sera of HCV patients compared with that in healthy controls. Serum hsa-miR-122, miR-134, miR-424-3p, and miR-629-5p were well identified. The ROC curves showed that miR-122, miR-134, miR-424-3p, and miR-629-5p could distinguish HCV patients with preferable sensitivity and specificity. In addition, Correlation analysis indicated serum miR-122 expression was positive correlation with ALT/AST levels. Functional analysis of target proteins of these miRNAs indicated the involvement of viral replication, inflammation, and cell proliferation.

CONCLUSION

HCV patients have a broad 'fingerprint' profile with dysregulated serum miRNAs compared with that in healthy controls. Among these, serum hsa-miR-122, miR-134, miR-424-3p, and miR-629-5p are identified as promising indication factors of the serum miRNA profile of HCV infection. Particularly, miR-122 could be one of serum biomarkers for early pathological process of HCV. However, more miRNA biomarkers and biological functions of these miRNAs require further investigation.

The Essential Component in DNA-Based Information Storage System: Robust Error-Tolerating Module

The size of digital data is ever increasing and is expected to grow to 40,000 EB by 2020, yet the estimated global information storage capacity in 2011 is <300 EB, indicating that most of the data are transient. DNA, as a very stable nano-molecule, is an ideal massive storage device for long-term data archive. The two most notable illustrations are from Church et al. and Goldman et al., whose approaches are well-optimized for most sequencing platforms - short synthesized DNA fragments without homopolymer. Here, we suggested improvements on error handling methodology that could enable the integration of DNA-based computational process, e.g., algorithms based on self-assembly of DNA. As a proof of concept, a picture of size 438 bytes was encoded to DNA with low-density parity-check error-correction code. We salvaged a significant portion of sequencing reads with mutations generated during DNA synthesis and sequencing and successfully reconstructed the entire picture. A modular-based programing framework - DNAcodec with an eXtensible Markup Language-based data format was also introduced. Our experiments demonstrated the practicability of long DNA message recovery with high error tolerance, which opens the field to biocomputing and synthetic biology.

Calcium hydroxylapatite injection for the patulous Eustachian tube

The function of the E-tube is to adjust the balance of both sides of the ear drum. The patulous Eustachian tube (PET) is a rare disease and a benign condition. So, most of the doctors ignored this disease. But, patients with PET suffer from ear fullness, autophony, hearing their own breathing, and etc. Many treatment methods have been introduced and injection is also one way of treating the disease. We introduce an injection technique for the treatment of PET using calcium hydroxylapatitie (Radiesse®).

Extratympanic observation of middle ear structure using a refractive index matching material (glycerol) and an infrared camera

High-resolution computed tomography has been used mainly in the diagnosis of middle ear disease, such as high-jugular bulb, congenital cholesteatoma, and ossicular disruption. However, certain diagnoses are confirmed through exploratory tympanotomy. There are few noninvasive methods available to observe the middle ear. The purpose of this study was to investigate the effect of glycerol as a refractive index matching material and an infrared (IR) camera system for extratympanic observation. 30% glycerol was used as a refractive index matching material in five fresh cadavers. Each material was divided into four subgroups; GN (glycerol no) group, GO (glycerol out) group, GI (glycerol in) group, and GB (glycerol both) group. A printed letter and middle ear structures on the inside tympanic membrane were observed using a visible and IR ray camera system. In the GB group, there were marked a transilluminated letter or an ossicle on the inside tympanic membrane. In particular, a footplate of stapes was even transilluminated using the IR camera system in the GB group. This method can be useful in the diagnosis of diseases of the middle ear if it is clinically applied through further studies.

The reversed internal magnet of cochlear implant after magnetic resonance imaging

Cochlear implants (CI) have now become a standard method of treating severe to profound hearing loss. Recently, the number of patients with CI has been rapidly increasing as the big benefits of CI become more widely known. Magnetic resonance imaging (MRI) has also become a routine diagnostic imaging modality, used in the diagnosis of common conditions, including stroke, back pain, and headache. We report our recent experience with a case in which internal magnet of the cochlear implant was reversed after 1.5-T lumbar spine MRI. This complication is managed successfully by reversing the orientation of the external magnet in the head coil.

An aptamer-based bio-barcode assay with isothermal recombinase polymerase amplification for cytochrome-c detection and anti-cancer drug screening

Based on a recently reported ultra-sensitive bio-barcode (BBC) assay, we have developed an aptamer-based bio-barcode (ABC) alternative to detect a cell death marker cytochrome-c (Cyto-c) and its subsequent application to screen anti-cancer drugs. Aptamer is a short single-stranded DNA selected from a synthetic DNA library by virtue of its high binding affinity and specificity to its target based on its unique 3D structure from the nucleotide sequence after folding. In the BBC assay, an antigen (Ag) in analytes is captured by a micro-magnetic particle (MMP) coated with capturing antibodies (Abs). Gold nanoparticles (NPs) with another recognition Ab against the same target and hundreds of identical DNA molecules of known sequence are subsequently added to allow the formation of sandwich structures ([MMP-Ab1]-Ag-[Ab2-NP-DNA]). After isolating the sandwiches by a magnetic field, the DNAs hybridized to their complementary DNAs covalently bound on the NPs are released from the sandwiches after heating. Acting as an Ag identification tag, these bio-barcode DNAs with known DNA sequence are then amplified by polymerase chain reaction (PCR) and detected by fluorescence. In our ABC assay, we employed a Cyto-c-specific aptamer to substitute both the recognition Ab and barcode DNAs on the NPs in the BBC assay; and a novel isothermal recombinase polymerase amplification for the time-consuming PCR. The detection limit of our ABC assay for the Cyto-c was found to be 10 ng/mL and this new assay can be completed within 3h. Several potential anti-cancer drugs have been tested in vitro for their efficacy to kill liver cancer with or without multi-drug resistance.