Endoscopic hydro-mastoidectomy, in which mastoidectomy is performed underwater, can be employed during transcanal endoscopic ear surgery for cholesteatoma removal. It was hypothesised that endoscopic hydro-mastoidectomy might take less time than endoscopic non-underwater mastoidectomy because the endoscope does not need to be removed for cleaning.

This study compared the mastoidectomy and total operative durations between the endoscopic hydro-mastoidectomy (n = 25) and endoscopic non-underwater drilling (control, n = 8) groups. Moreover, it compared the size of resected areas of the external auditory canal between the two groups.

The mastoidectomy time of the endoscopic hydro-mastoidectomy group was significantly shorter than that of the control group (p < 0.01). The total operative time did not differ significantly between the endoscopic hydro-mastoidectomy and control groups (p = 0.17). The resected area was significantly larger in the endoscopic hydro-mastoidectomy group than in the control group (p < 0.05).

Endoscopic hydro-mastoidectomy enables more extensive bone resection within a shorter period.

Three-dimensional endoscopes provide a stereoscopic view of the operating field, facilitating depth perception compared to two-dimensional systems, but are not yet widely accepted. Existing research addresses performance and preference, but there are no studies that quantify anatomical orientation in endoscopic ear surgery.

Participants (n = 70) were randomised in starting with either the two-dimensional or three-dimensional endoscope system to perform one of two tasks: anatomical orientation using a labelled three-dimensional printed silicone model of the middle ear, or simulated endoscopic skills. Scores and time to task completion were recorded, as well as self-reported difficulty, confidence and preference.

Novice surgeons scored significantly higher in a test of anatomical orientation using three-dimensional compared to two-dimensional endoscopy (p < 0.001), with no significant difference in the speed of simulated endoscopic skills task completion. For both tasks, there was lower self-reported difficulty and increased confidence when using the three-dimensional endoscope. Participants preferred three-dimensional over two-dimensional endoscopy for both tasks.

The findings demonstrate the superiority of three-dimensional endoscopy in anatomical orientation, specific to endoscopic ear surgery, with statistically indistinguishable performance in a skills task using a simulated trainer.

To examine the effects of mastoid and middle-ear volume on the anatomical and functional success of type 1 tympanoplasty in paediatric patients.

This study included 45 paediatric patients who underwent type 1 cartilage tympanoplasty. Patients’ demographic data, pre- and post-operative audiological evaluation results, and post-operative graft status were evaluated. Middle-ear and mastoid cavity volumes were calculated (in cubic centimetres) using temporal bone high-resolution computed tomography. Middle-ear and mastoid cavity volume values were compared between patients with and without post-operative anatomical and functional success.

Anatomical success was achieved in 82.2 per cent of patients (n = 37), and functional success in 68.9 per cent (n = 31). When anatomical success and failure groups were compared, a statistically significant difference was found in mean mastoid volume (p = 0.037), while there was no significant difference in relation to mean middle-ear volume (p = 0.827). The comparison of functional success and failure groups revealed no significant difference in mean mastoid volume (p = 0.492) or middle-ear volume (p = 0.941).

The study showed that mastoid pneumatisation volume affects surgical success in paediatric tympanoplasty.

Advice to patients following grommet insertion and waterproofing can vary from clinician to clinician. A laboratory based experiment was performed to determine at what depth water contamination would occur through various grommet tubes.

A novel experimental ear model was developed using an artificial tympanic membrane and ventilation tubes. Water contamination was identified using an effervescent solid that reacts when in contact with water. Measures of dispersion were used to describe the results.

The average depth of water contamination was: 19.64 mm (range = 11–33 mm, standard deviation = 5.55 mm) using a Shepard grommet; 20.84 mm (range = 18–26 mm, standard deviation = 1.97 mm) with a titanium grommet; and 21.36 mm (range = 18–33 mm, standard deviation = 3.03 mm) using a T-tube. Water contamination was possible at depths of 11–33 mm. The average pressure at water effervescent activation was 0.20 kPa.

Submersion underwater at any depth with grommets is likely to lead to middle-ear contamination. These findings are concordant with clinical studies.

This study aimed to analyse if there were any associations between patulous Eustachian tube occurrence and climatic factors and seasonality.

The correlation between the monthly average number of patients diagnosed with patulous Eustachian tube and climatic factors in Seoul, Korea, from January 2010 to December 2016, was statistically analysed using national data sets.

The relative risk for patulous Eustachian tube occurrence according to season was significantly higher in summer and autumn, and lower in winter than in spring (relative risk (95 per cent confidence interval): 1.334 (1.267–1.404), 1.219 (1.157–1.285) and 0.889 (0.840–0.941) for summer, autumn and winter, respectively). Temperature, atmospheric pressure and relative humidity had a moderate positive (r = 0.648), negative (r = –0.601) and positive (r = 0.492) correlation with the number of patulous Eustachian tube cases, respectively.

The number of patulous Eustachian tube cases was highest in summer and increased in proportion to changes in temperature and humidity, which could be due to physiological changes caused by climatic factors or diet trends.

This study aimed to compare the necessary scutum defect for transmeatal visualisation of middle-ear landmarks between an endoscopic and microscopic approach.

Human cadaveric heads were used. In group 1, middle-ear landmarks were visualised by endoscope (group 1 endoscopic approach) and subsequently by microscope (group 1 microscopic approach following endoscopy). In group 2, landmarks were visualised solely microscopically (group 2 microscopic approach). The amount of resected bone was evaluated via computed tomography scans.

In the group 1 endoscopic approach, a median of 6.84 mm3 bone was resected. No statistically significant difference (Mann–Whitney U test, p = 0.163, U = 49.000) was found between the group 1 microscopic approach following endoscopy (median 17.84 mm3) and the group 2 microscopic approach (median 20.08 mm3), so these were combined. The difference between the group 1 endoscopic approach and the group 1 microscopic approach following endoscopy plus group 2 microscopic approach (median 18.16 mm3) was statistically significant (Mann–Whitney U test, p < 0.001, U = 18.000).

This study showed that endoscopic transmeatal visualisation of middle-ear landmarks preserves more of the bony scutum than a microscopic transmeatal approach.

This study aimed to evaluate the clinical features and outcomes of patients with middle-ear granulation pathologies associated with attic retractions.

The clinical records of adult patients with middle-ear granulation pathologies and attic retractions confirmed via computed tomography and surgical exploration between January 2012 and January 2019 were retrospectively reviewed.

A total of 59 patients were included. Endoscopic examination showed a normal pars tensa but retraction of the pars flaccida in all patients. No granulation tissue or debris were observed. Low-pitched tinnitus was the principal complaint of 55 patients (100 per cent), followed by ear fullness (14 patients, 23.7 per cent). Of the 59 patients, 52 patients (88.1 per cent) underwent canal wall up mastoidectomy and 7 patients (11.9 per cent) underwent endoscopic endaural atticoantrotomy. No ossicular chain destruction was evident. All patients were followed up for 12 months. Tinnitus disappeared completely in 48 patients (81.4 per cent), improved significantly in 9 patients (15.3 per cent) and improved mildly in 2 patients (3.3 per cent).

A granulation tissue pathology should be considered when a patient complains of low-pitched tinnitus and exhibits retraction of the pars flaccida. Computed tomography and surgical exploration should be scheduled.

This study aimed to compare the outcomes of ventilation tube insertion and balloon Eustachian tuboplasty as a first line treatment for otitis media with effusion in children.

This was a retrospective evaluation of 62 children, 30 cases that underwent balloon Eustachian tuboplasty (group 1) and 32 cases that underwent ventilation tube insertion (group 2), from July 2016 to April 2018.

The pre-operative air–bone gap of patients who underwent balloon Eustachian tuboplasty was 15–35 dB (mean: 27.6 ± 8.2 dB). The mean pre-operative air–bone gap decreased to 9.6 dB after a mean of 14.4 months (p < 0.05). The air–bone gap decreased from 25.6 dB to 17.6 dB in the ventilation tube group. There was a significant improvement in the air–bone gap values in both groups; however, this decrease was significantly higher in the balloon Eustachian tuboplasty group (p = 0.043).

Balloon Eustachian tuboplasty may be an effective and safe method for use as a first-line treatment of otitis media with effusion in children.

Patulous Eustachian tube appears to be caused by a concave defect in the anterolateral wall of the tubal valve of the Eustachian tube. This study aimed to compare the clinical features of patulous Eustachian tube patients with or without a defect in the anterolateral wall of the tubal valve.

Sixty-six patients with a patulous Eustachian tube completed a questionnaire, which was evaluated alongside endoscopic findings of the tympanic membrane, nasal cavity and Eustachian tube orifice.

Females were more frequently diagnosed with a patulous Eustachian tube, but the valve defect was more common in males (p = 0.007). The ratio of patulous Eustachian tube patients with or without defects in the anterolateral wall of the tubal valve was 1.6:1. Weight loss in the previous six months and being refractory to conservative management were significantly associated with the defect (p = 0.035 and 0.037, respectively). Symptom severity was significantly higher in patients with the defect.

Patulous Eustachian tube patients without a defect in the anterolateral wall of the tubal valve can be non-surgically treated more often than those with the defect. Identification of the defect could assist in making treatment decisions for patulous Eustachian tube patients.

Rate of learning is often cited as a deterrent in the use of endoscopic ear surgery. This study investigated the learning curves of novice surgeons performing simulated ear surgery using either an endoscope or a microscope.

A prospective multi-site clinical research study was conducted. Seventy-two medical students were randomly allocated to the endoscope or microscope group, and performed 10 myringotomy and ventilation tube insertions. Trial times were used to produce learning curves. From these, slope (learning rate) and asymptote (optimal proficiency) were ascertained.

There was no significant difference between the learning curves (p = 0.41). The learning rate value was 68.62 for the microscope group and 78.71 for the endoscope group. The optimal proficiency (seconds) was 32.83 for the microscope group and 27.87 for the endoscope group.

The absence of a significant difference shows that the learning rates of each technique are statistically indistinguishable. This suggests that surgeons are not justified when citing ‘steep learning curve’ in arguments against the use of endoscopes in middle-ear surgery.

Understanding the pattern of middle-ear cholesteatoma becomes pertinent with the rise of endoscopic surgery as surgeons decide on the optimal approach to visualise and extirpate disease. With modifications to the Telmesani attic–tympanum–mastoid staging system, this study aimed to evaluate the commonest patterns of middle-ear cholesteatoma and their implications for surgical approach.

A retrospective study was conducted in a single tertiary institution in Singapore. All patients undergoing cholesteatoma surgery between January 2012 and June 2015 were included. Staging of cholesteatoma was based on clinical assessment corroborated by radiological findings.

Out of the 55 ears included, 98.2 per cent had cholesteatoma involving the attic. The disease extended into the mastoid antrum and beyond in 43 cases (78.2 per cent). The facial recess and/or sinus tympanum was affected in 26 cases (47.3 per cent).

The majority of cholesteatoma cases present with extensive attic disease and significant mastoid involvement. In these cases, endoscopes may be best suited to adjunctive rather than exclusive use in surgery.

This study sought to compare disease recidivism rates between canal wall up mastoidectomy and a canal wall down with obliteration technique.

Patients undergoing primary cholesteatoma surgery at our institution over a five-year period (2013–2017) using the aforementioned techniques were eligible for inclusion in the study. Rates of discharge and disease recidivism were analysed using chi-square statistics.

A total of 104 ears (98 patients) were included. The mean follow-up period was 30 months (range, 12–52 months). A canal wall down with mastoid obliteration technique was performed in 55 cases and a canal wall up approach was performed in 49 cases. Disease recidivism rates were 7.3 per cent and 16.3 per cent in the canal wall down with mastoid obliteration and canal wall up groups respectively (p = 0.02), whilst discharge rates were similar (7.3 per cent and 10.2 per cent respectively).

Our direct comparative data suggest that canal wall down mastoidectomy with obliteration is superior to a canal wall up technique in primary cholesteatoma surgery, providing a lower recidivism rate combined with a low post-operative ear discharge rate.

Detection and valid measurements of distortion product otoacoustic emissions are not influenced by cochlear status alone, but also by middle-ear status. There is a need to understand the use of ultra-high frequency distortion product otoacoustic emissions in cases of abnormal distortion product otoacoustic emission findings for conventional frequencies related to the middle-ear condition.

The present study investigated distortion product otoacoustic emission input–output functions in conventional and ultra-high frequencies in: 37 adults with chronic suppurative otitis media (clinical group) and 37 adults with normal hearing sensitivity (control group).

There were significant reductions in distortion product otoacoustic emission amplitude and mean signal-to-noise ratio in the clinical group compared to the control group, especially for conventional frequencies.

There was a significant reduction in the rate of ears with measurable distortion product otoacoustic emissions in the clinical group, especially for conventional frequencies. The effect of chronic suppurative otitis media was more pronounced in the conventional frequency range compared to the smaller effect seen in the ultra-high frequency range.

This case report presents a middle-ear osteoma mimicking otosclerosis that was located at the promontory. The osteoma was successfully excised using an endoscopic transcanal approach without any complication.

A 21-year-old man presented with a 4-year history of progressive conductive hearing loss (47 dB with a 30-dB air–bone gap) with intermittent tinnitus of recent onset in his right ear. Endoscopic transcanal middle-ear exploration showed that an osteoma located on the promontory was restricting the mobility of the stapes by affecting the anterior crus of the stapes. After transcanal resection of the osteoma, pure tone audiometry improved to 23 dB with a 5-dB air–bone gap. Tinnitus resolved spontaneously without any additional treatment.

Promontory osteomas, a rare and usually asymptomatic clinical entity, should be taken into consideration in the differential diagnosis in patients with progressive conductive hearing loss and tinnitus with intact stapedial reflexes and normal otoscopic findings.

To assess the effect of topical betahistine on Eustachian tube function in subjectively abnormal subjects in a hyperbaric chamber.

Active and passive Eustachian tube function was examined using tympanometry in a pressure chamber.

Active Eustachian tube function was tested against the negative middle ear pressure induced by increasing the chamber pressure to +3 kPa. One voluntary swallow decreased middle-ear pressure by a mean of 1.36 kPa. Passive Eustachian tube function was tested by measuring spontaneous Eustachian tube openings as the chamber pressure dropped from +10 kPa to ambient. Four distinct patterns of Eustachian tube behaviour were seen, three of which indicated Eustachian tube dysfunction. Betahistine had no positive effect on Eustachian tube opening, although previous animal studies had suggested a beneficial effect.

Topical betahistine had no effect on Eustachian tube function. Combining a hyperbaric chamber with tympanometry proved ideal for evaluating Eustachian tube function.

In order to remove a cholesteatoma in the mastoid under transcanal endoscopic ear surgery, it is necessary to perform transcanal endoscopic mastoidectomy. Bone dust and blood, however, obscure the surgical field. A novel endoscopic hydro-mastoidectomy technique was developed, in which the operator performs the mastoidectomy ‘underwater’ using a lens cleaning system that provides saline perfusion in the surgical space.

A curved round coarse diamond bur is attached to an otological drill. A lens cleaning sheath is fitted to the endoscope. The surgeon controls the infusion of saline solution by stepping on a footswitch of the power console.

Endoscopic hydro-mastoidectomy washes out bone dust and blood from the surgical field, improving the surgical view during mastoidectomy. Additionally, the operator can easily control the flow of saline perfusion.

This technique provides a clear surgical view by washing out bone dust and blood from the surgical area. The setup for endoscopic hydro-mastoidectomy technique is easy and the operator needs only to buy sheaths if they already own the power console, as many otological and rhinological surgeons do.

To recount experience with cerebrospinal fluid otorrhoea and temporal bone meningoencephalocele repair in a tertiary care hospital.

A retrospective review was conducted of 16 cerebrospinal fluid otorrhoea and meningoencephalic herniation patients managed surgically from 1991 to 2016.

Aetiology was: congenital (n = 3), post-traumatic (n = 2), spontaneous (n = 1) or post-mastoidectomy (n = 10). Surgical repair was undertaken by combined middle cranial fossa and transmastoid approach in 3 patients, transmastoid approach in 2, oval window plugging in 1, and subtotal petrosectomy with middle-ear obliteration in 10. All patients had successful long-term outcomes, except one, who experienced recurrence after primary stage oval window plugging, but has been recurrence-free after second-stage subtotal petrosectomy with middle-ear obliteration.

Dural injury or exposure in mastoidectomy may lead to cerebrospinal fluid otorrhoea or meningoencephalic herniation years later. Congenital, spontaneous and traumatic temporal bone defects may present similarly. Middle cranial fossa dural repair, transmastoid multilayer closure and subtotal petrosectomy with middle-ear obliteration were successful procedures. Subtotal petrosectomy with middle-ear obliteration offers advantages over middle cranial fossa dural repair alone; soft tissue closure is more robust and is preferred in situations where hearing preservation is not a priority.

Surgery for chronic suppurative otitis media performed in low- and middle-income countries creates specific challenges. This paper describes the equipment and a variety of techniques that we find best suited to these conditions. These have been used over many years in remote areas of Nepal.

Extensive chronic suppurative otitis media is frequently encountered, with limited pre-operative investigation or treatment possible. Techniques learnt in better-resourced settings with good follow up need to be modified. The paper describes surgical methods suitable for resource-poor conditions, with rationales. These include methods of tympanoplasty for subtotal wet perforations, hearing reconstruction in wet ears and open cavities, large aural polyps, and canal wall down mastoidectomy with cavity obliteration. Various types of autologous ossiculoplasty are described in detail for use in the absence of prostheses. The following topics are discussed: decision-making for surgery on wet or best hearing ears, children, bilateral surgery, working with local anaesthesia, and obtaining adequate consent in this environment.

To investigate the evidence for balloon dilatation of the eustachian tube using a transtympanic approach.

A systematic search of several databases was conducted (using the search terms ‘dilation’ or ‘dilatation’, and ‘balloon’ and ‘eustachian tube’). Only studies that used a transtympanic approach for the procedure were included. These studies were then assessed for risk of bias.

Three studies were included. Each of these studies was a limited case series, with two performed on human subjects and one on human cadavers. Results of safety and efficacy are conflicting. There is a high risk of bias overall.

At present, there is a very narrow evidence base for transtympanic balloon dilatation of the eustachian tube. There are a number of advantages and disadvantages of the technique. Previously identified and theoretical safety concerns will need to be addressed thoroughly in future studies prior to wider clinical use.

A systematic review was performed to evaluate the role and effectiveness of head bandages after routine elective middle-ear surgery.

Studies that compared the effectiveness of head bandage use after elective middle-ear surgery (e.g. myringoplasty, mastoidectomy and cochlear implantation) were identified using the following databases: Ovid Medline and Embase, the Ebsco collections, the Cochrane Library, PubMed, and Google Scholar. An initial search identified 71 articles. All titles and abstracts were reviewed. Thirteen relevant articles were inspected in more detail; of these, only five met the inclusion criteria. These included three randomised, controlled trials, one retrospective case series and one literature review.

The three randomised, controlled trials (level of evidence 1b) showed no statistically significant differences in post-operative outcomes (in terms of complications) associated with head bandage use in middle-ear surgery. This finding was supported by the retrospective case series involving patients undergoing cochlear implantation.

Current available evidence shows no advantage of head bandage use after middle-ear surgery. Head bandages may not be required after routine, uncomplicated middle-ear surgery.