Non-explosive blast injury of the ear

Incidence and Epidemiology of Traumatic Tympanic Membrane Rupture: A National Trauma Data Bank Analysis

The incidence of traumatic tympanic membrane rupture (TTMR) has increased over recent decades. The association of certain external injury causes and bone fracture patterns with TTMR is anecdotal. It has been suggested that a diagnosis of TTMR may be missed during the acute trauma admission. The authors sought to evaluate the incidence of TTMR according to external injury cause and evaluate the association of skull fracture patterns with TTMR using a national trauma database. A cross-sectional analysis of trauma encounters was conducted using the National Trauma Data Bank (NTDB) from 2008 to 2015. Demographic and injury data were abstracted. Poisson regression was used to determine the incidence rate ratios of tympanic membrane rupture by external injury cause and logistic regression was used to estimate odds ratios (OR) of TTMR by skull fracture type. A total of 8214 patients were identified with TTMR during acute admission. The majority were on average 30 years old, 76% male, 71% White, had a mean Injury Severity Score of 14, and 42% were admitted to level I centers. The incidence rate ratio was only higher in lightning related injuries [5.262; 95% confidence interval (CI): 4.194-6.602] when using those caused by explosives as a reference. Basilar skull (OR: 12.95; 95% CI: 12.095-12.866) and cranial vault (OR: 2.938; 95% CI: 2.647-3.260) fractures were most associated with TTMR. The high incidence TTMR in association with certain external causes of injury and types of skull fractures should drive screening in the acute setting in order to increase detection and reduce morbidity from missed injuries.

[Hearing dynamics in acute traumatic perforation of the tympanic membrane after application of blood plasma enriched with platelet growth factors]

OBJECTIVE

The article considers the possibility of treating patients with acute traumatic perforation of the eardrum with a single application of blood plasma enriched with platelet-derived growth factors in the perforation area. As a result of the studies, it was found that the acceleration of its closure and the restoration of hearing.

MATERIAL AND METHODS

The study included 43 patients with unilateral acute PBP of various etiologies (Table 1). Patients were divided into 2 groups - the main - 24 patients (10 men and 14 women), the average age - 30±9.7 years and the control - 19 patients (9 men and 10 women), the average age - 26.5±6.37 years. The compared groups did not reliably differ in age, gender, frequency and severity of hearing impairment.

RESULTS

Analyzing the results, we can confidently talk about the beneficial effect of blood plasma enriched in platelet-derived growth factors on the speed, completeness of closure of traumatic perforation of the eardrum and the dynamics of restoration of auditory function. The use of blood plasma enriched with platelet growth factors led to a regular reduction in the time and increase in the frequency of cases of early closure of perforated eardrum, as well as improvement and restoration of auditory function according to the results of tonal threshold audiometry and otoacoustic emission in dynamics.

CONCLUSION

Being generally available even in outpatient practice, the method of a single application of blood plasma enriched with platelet growth factors in the area of perforation of the tympanic membrane can significantly accelerate the healing process of the tympanic membrane, while improving the quality of life of the patient.

Audiological characteristics of the contralateral ear in patients with unilateral physical non-explosive ear trauma

Objectives

To document the frequency of occurrence and types of symptoms experienced in the contralateral ear in patients with unilateral physical non-explosive (UPN) ear trauma and to compare the audiometric and tympanometric parameters between asymptomatic and symptomatic contralateral ears.

Design

Prospective analytical clinical study Setting: Specialized (Ear, Nose, and Throat) clinic of a tertiary health institution. Participants: Patients with UPN ear trauma who presented within the first week of the incident. Main outcome measures: Otologic symptoms in the contralateral ear in UPN ear trauma.

Results

Eighteen out of 53 patients (34.0%) experienced symptoms in the contralateral ear. The symptoms were tinnitus in 77.8% (14/18), hearing loss in 66.7% (12/18), and ear blockage in 27.8% (5/18). There was hearing loss in 38/53 (71.7%) of contralateral ears. Hearing loss type and PTAv at the low frequencies were not significantly different (p=0.142), but other audiometric parameters were significantly different between asymptomatic and symptomatic contralateral ears (p<0.05 in all). Type C tympanogram was more prominent in the symptomatic contralateral ear. There was a statistically-significant difference in the type of tympanogram between the two categories of patients (p=0.018). There was no difference in acoustic reflex between the two categories of patients (p=0.095).

Conclusions

The contralateral ear may be affected in up to one-third of patients with UPN ear trauma, and experience otologic symptoms similar to those of the traumatized ears. Audiologic and audiometric parameters were abnormal in most of the contralateral ears. The two ears must be assessed thoroughly in cases of UPN ear trauma.

Blast-Induced Cholesteatomas After Spontaneous Tympanic Membrane Healing

OBJECTIVES

To characterize blast-induced cholesteatomas (BIC) in terms of symptoms, presentation, and location within the middle ear cleft (MEC).

DESIGN

A search for all English language articles in "MEDLINE" via "PubMed" and "Google Scholar" was conducted.

RESULTS

A total of 67 ears with BIC were included. Fifty-eight ears in which the traumatic perforation failed to spontaneously close were excluded, leaving seven case reports (eight patients, nine ears) for statistical analysis. Time between blast exposure to spontaneous tympanic membrane (TM) closure was 16 days to 10 months. Time between blast exposure and cholesteatoma diagnosis was 5 months to 4 years. The cholesteatomas were diagnosed due to symptoms in two ears, as asymptomatic finding on physical examination in one ear and as asymptomatic finding in axial imaging in three ears.

CONCLUSIONS

BICs can develop behind intact tympanic membrane or along with TM perforation. Based on the current review, when a TM perforation and spontaneous healing were documented, after blast exposure, MRI scan is an integral component of the follow-up. The optimal timing for MRI performance after blast exposure, is yet to be identified.

Efficacy of EGF and Gelatin Sponge for Traumatic Tympanic Membrane Perforations: A Randomized Controlled Study

OBJECTIVE

To compare the outcomes of epidermal growth factor (EGF) and gelatin sponge patch treatments for traumatic tympanic membrane perforations.

STUDY DESIGN

Prospective, randomized, controlled.

SETTING

University-affiliated teaching hospital.

SUBJECTS AND METHODS

In total, 141 perforations encompassing >50% of the eardrum were randomly divided into 3 groups: EGF (n = 47), gelatin sponge patch (n = 47), and observation (n = 47). The edges of the perforations were not approximated. The closure rate, mean closure time, and infection rate were evaluated at 6 months and the related factors analyzed.

RESULTS

A total of 135 perforations were analyzed. At 6 months, the closure rates were 97.8%, 86.7%, and 82.2% in the EGF, gelatin sponge patch, and spontaneous healing groups, respectively (P = .054). The mean ± SD closure time was 11.12 ± 4.60, 13.67 ± 5.37, and 25.65 ± 13.32 days in the EGF, gelatin sponge patch, and spontaneous healing groups, respectively (P < .001). In addition, the presence of infection was not significantly associated with rate of closure in any group.

CONCLUSIONS

As compared with spontaneous healing, daily application of EGF and gelatin sponge patching reduced the closure time of traumatic tympanic membrane perforations. EGF treatment had a higher closure rate and shorter closure time but resulted in otorrhea. By contrast, gelatin sponge patches did not improve the closure rate or cause otorrhea but required repeated patch removal and reapplication. Thus, the appropriate treatment should be selected according to patient need.

Application of Platelet Rich Fibrin Matrix to Repair Traumatic Tympanic Membrane Perforations: A Pilot Study

Trauma in the form of instrumentation, slap, blast, accident, and sporting injury can result in tympanic membrane (TM) perforations which spontaneously recover in 53-94%. The closure rates of TM perforation due to above causes do not vary greatly; however, some otolaryngologists prefer to perform immediate microsurgical procedures to accelerate the recovery process. Our aim is to study the efficacy of Trichloroacetic acid (TCA) Chemical Cauterization (50%) and Platelet rich fibrin (PRF) Plug Myringoplasty technique in healing traumatic tympanic membrane perforations. To evaluate the preoperative and postoperative hearing outcome from the procedure and compare them. Study design is prospective study. A pilot study was carried out amongst selected 25 patients with central perforations in the Department of ENT, for duration of 2 years from July 13 to July 15. All 25 patients underwent PTA assessment & TCA (50%) and Autologous PRF Plug Myringoplasty technique done and follow up to 6 months postoperatively. The success rate traumatic tympanic membrane closure was found to be 92%. Pre- and post-operative hearing assessments of each patient were done & showed statistically significant air-bone gap closure with success rate of 88% (p < 0.05). From this study, the closure rate in traumatic tympanic membrane perforation by TCA (50%) and PRF Plug Myringoplasty technique was 92% with statistically significant hearing improvement (88%). This technique can be recommended as a time and cost effective office based procedure for treatment of traumatic tympanic membrane perforations.

The effects of fibroblast growth factor-2 delivered via a Gelfoam patch on the regeneration of myringosclerotic traumatic eardrum perforations lying close to the malleus

OBJECTIVE

We evaluated the effects of fibroblast growth factor-2 (FGF-2) delivered via a Gelfoam patch on the regeneration of myringosclerotic traumatic tympanic membrane perforations (TMPs) lying close to the malleus.

STUDY DESIGN

A prospective, randomized, controlled clinical study.

SETTING

A university-affiliated teaching hospital.

SUBJECTS AND METHODS

We prospectively analyzed, in a randomized manner, the outcomes of treatment for traumatic TMPs constituting >25% of the tympanic membrane. The closure rates, closure times, and otorrhea rates were compared among patients treated via FGF-2-containing Gelfoam patches, Gelfoam patches alone, and observation only.

RESULTS

We analyzed data from 138 patients. The perforation closure rates in the FGF-2 plus Gelfoam patch, Gelfoam patch, and observation alone groups were 97.9, 89.8, and 70.7%, respectively. Both the FGF-2 plus Gelfoam and Gelfoam alone groups exhibited significantly higher closure rates than the observational group (both p<0.05).The mean closure times were 15.7±5.1, 24.8±4.9, and 35.7±9.2days in the FGF-2 plus Gelfoam patch, Gelfoam patch alone, and observation alone groups, respectively. The FGF-2 plus Gelfoam patch group exhibited a significantly shorter closure time than the Gelfoam patch alone and observation alone groups (p<0.05). The incidences of purulent otorrhea were 14.6, 6.1, and 4.9% in the FGF-2 plus Gelfoam patch, Gelfoam patch alone, and observation alone groups, respectively. Surprisingly, 7 of 7 (100.0%) perforations associated with purulent otorrhea completely closed in the FGF-2 plus Gelfoam patch group; however, no such perforation healed in either the Gelfoam alone or observation alone group.

CONCLUSIONS

FGF-2 plus Gelfoam patching significantly shortened the closure time compared to observation and Gelfoam patching alone, and it significantly improved the closure rate (compared to observation alone) of myringosclerotic perforations lying close the malleus. FGF-2 plus Gelfoam patching is a valuable, minimally invasive alternative treatment that may be readily applied to outpatient settings.

Assessment and spontaneous healing outcomes of traumatic eardrum perforation with bleeding

OBJECTIVE

This study investigated the influence of the degree of bleeding from the remnant eardrum on the spontaneous healing of human traumatic tympanic membrane perforations (TMPs).

STUDY DESIGN

A case series with chart review.

SETTING

A tertiary university hospital.

MATERIALS AND METHODS

The clinical records of traumatic TMP patients who met the case selection criteria were retrieved and categorized into two groups based on the documented degree of bleeding from the remnant eardrum: with and without bleeding. The demographic data and spontaneous healing outcomes (i.e., healing rate and duration) of these two TMP types were analyzed using the chi-squared test or t-test.

RESULTS

One-hundred and eighty-eight cases met the inclusion criteria and were analyzed. Of these, 58.5% had perforations without bleeding and the remaining 41.5% had perforations with bleeding. The overall closure rate at the end of the 3-month follow-up period was 90.9% for perforations without bleeding and 96.2% for perforations with bleeding; the difference was not statistically significant (P>0.05). However, the average closure time differed significantly between the two groups (P<0.05): 29.4±3.7days for perforations without bleeding and 20.6±9.2days for perforations with bleeding. The closure rate was significantly different between the groups (62 vs. 15.6%, P<0.01) within 2weeks for medium-sized perforations. In total, 11 (39.3%) large-sized perforations achieved complete closure in the group with bleeding, while none of the large-sized perforations closed in the group without bleeding within 2weeks. The closure rate of medium-sized perforations was not significantly different (79.2 vs. 92%, P>0.05) between the groups without and with bleeding within 4weeks, while the closure rate of large-sized perforations was significantly different between the groups without and with bleeding (27.2 vs. 75%, P=0.0).

CONCLUSION

This study shows that traumatic TMPs with bleeding significantly shortened the closure time compared to TMPs without bleeding. This finding indicates a significant correlation between the prognosis of traumatic TMPs and the degree of eardrum bleeding: severe bleeding from and a hematoma in the remnant eardrum appear to be good signs.

Use of a platelet-rich fibrin membrane to repair traumatic tympanic membrane perforations: a comparative study

OBJECTIVES

(1) To evaluate the effects of a platelet-rich fibrin (PRF) membrane in the repair of traumatic tympanic membrane (TM) perforations; and (2) to compare the use of a PRF membrane with the paper patch technique with regard to recovery rates, healing time, and correction of the mean air-bone gap.

METHODS

A randomized, prospective analysis was performed for 60 patients who were treated for traumatic TM perforations using one of the two methods. Closure rate, speed of healing, and hearing gain were compared between the PRF (Group 1) and paper patch (Group 2) groups.

RESULTS

Closure was obtained in 28 (93%) perforations in Group 1 and 25 (83%) perforations in Group 2 (p > 0.05). On day 10, full closure of the TM was observed in 24 (80%) patients in Group 1 and 16 (53%) patients in Group 2 (p < 0.05). The improvement in the mean air-bone gap was 14.1 dB in Group 1 and 12.4 dB in Group 2 on post-operative day 45 (p < 0.05).

CONCLUSIONS

In comparison with the paper patch method, PRF, a new method, provided more rapid healing with more successful audiological results, and with no requirement for a second procedure.

Risk factors affecting human traumatic tympanic membrane perforation regeneration therapy using fibroblast growth factor-2

OBJECTIVE

The use of growth factors to achieve closure of human traumatic tympanic membrane perforations (TMPs) has recently been demonstrated. However, pretreatment factors affecting healing outcomes have seldom been discussed. The objective of this study was to evaluate pretreatment factors contributing to the success or failure of healing of TMPs using fibroblast growth factor-2 (FGF-2).

DESIGN AND PARTICIPANTS

A retrospective cohort study of 99 patients (43 males, 56 females) with traumatic TMPs who were observed for at least 6 months after FGF-2 treatment between March 2011 and December 2012. Eleven factors considered likely to affect the outcome of perforation closure were evaluated statistically using univariate and multivariate logistic regression analysis.

INTERVENTIONS

Each traumatic TMP was treated by direct application of FGF-2.

MAIN OUTCOME MEASURES

Complete closure versus failure to close.

RESULTS

In total, 99 patients were analyzed. The total closure rate was 92/99 (92.9%) at 6 months; the mean closure time was 10.59 ±  6.81 days. The closure rate did not significantly differ between perforations with or without inverted edges (100.0% vs. 91.4%, p = 0.087), among different size groups (p = 0.768), or among different periods of exposure to injury (p = 0.051). However, the closure rate was significantly different between the high- and low-dose FGF-2 groups (85.0% vs. 98.3%, p = 0.010) and between perforations where the umbo or malleus was or was not involved in perforation (85.4% vs. 98.3%, p = 0.012). Additionally, univariate logistic regression analysis tests showed that it was difficult to achieve healing of these perforations with a history of chronic otitis media or residual TM calcification (p = 0.006), the umbo or malleus was involved in perforation (p = 0.038), and with a high dose of FGF-2 (p = 0.035) compared with control groups. Multivariate logistic regression analysis showed that only a history of chronic otitis media and residual TM calcification and perforation close to the umbo or malleus were associated with non-healing of the TM perforation (p = 0.03 and p = 0.017, respectively) with relative risk factors.

CONCLUSIONS

Direct application of FGF-2 can be used in all traumatic TMPs, the size of the perforation and inverted edges did not affect the closure rate, and the most beneficial dose was sufficient to keep the residual eardrum environment moist, but without adding liquid. Additionally, multivariate logistic regression analysis revealed that a large perforation was not a major risk factor for nonhealing of TM perforations. However, a history of chronic otitis media, residual TM calcification and involvement of the umbo or malleus in perforation were significant risk factors.

Ear trauma in orlu, Nigeria: a five-year review

To review the presentation, types and aetiology of ear trauma and various factors affecting ear trauma in our patients over a 5 year period. All patients treated for ear trauma over a 5 year period were studied using their clinical records. Data extracted were analysed using SPSS version 11 software. The results were presented in simple descriptive and tabular forms. Forty-one patients, 18(43.90%) males and 23(56.10%) females were studied, ages 12-43 years, average 26.3 + 5 years. Blows/Slaps (65.85%) from assault was the commonest aetiology while bleeding from the ear (73.17%), hearing loss (70.73%) and tympanic membrane perforation (68.29%) were the most frequent presentations. Ear trauma is common and mostly affects the tympanic membrane. Sudden increase in canal pressure from blows/slaps was the major mechanism of injury. Management outcome was good except for few late presenters with compilations.

Traumatic tympanic membrane perforations: a study of etiology and factors affecting outcome

OBJECTIVE

The purposes of this study were to determine the factors involved in the spontaneous healing and to profile the various etiologies of traumatic tympanic membrane (TM) perforation.

METHODS

A retrospective review was performed on 729 cases of traumatic TM perforation diagnosed in the emergency department and outpatient clinic from January 2007 to March 2011.

RESULTS

A total 641 patients with traumatic TM perforations were enrolled in the study. The group consisted of 320 male and 321 female patients with a mean age of 33.6 years (3-79 years). The types of trauma included compression injury (554 patients), blast injury (55 patients), and instrumental injury (32 patients). The causes of conflict by a slap or a fist were spouse or lover (52%), parents and sibling (3%), school teachers (4%), schoolmate (12%), state police and prisoner (7%), and blow against the ear during street fight (22%). Of the 641, 137 were lost during follow-up; of the remaining 504, perforations closed spontaneously in 451 (89%), within a mean of 27.4 days. Wet perforations with bloody or watery discharge significantly improved the healing rate (P < .01) and shortened the average perforation closure time (P < .01), as compared with dry perforations. Although the perforation that involved malleus or umbo damage did not significantly affect the healing rate (P > .05), a significantly prolonged closure time (41.6 vs 23.8 days) was observed as compared with no damage. However, the curled edges did not also affect the outcome of spontaneous healing; the healing rate was 91% and 88% (P > .05), and the average closure time was 28.1 and 26.7 days (P > .05), respectively, for with and without curler edges. By perforation size, the overall healing rate was 92% and 54% (P < .01), and the average closure time was 22.8 and 47.3 days (P < .01), respectively, for small and larger perforations. Moreover, 7 patients had neomembrane formation on follow-up, 2 developed cholesteatoma, 1 developed tympanosclerosis, and 1 developed facial paralysis.

CONCLUSION

In our experience, domestic violence and street fight were the most common causes of the traumatic TM perforation. Traumatic TM perforations have excellent prognosis. However, preexisting tympanosclerosis and the perforation that involved malleus or umbo damage could lengthen the healing time of perforation, Wet perforations with bloody or watery discharge accelerate the healing, but the curled edges did not affect the outcome of spontaneous healing.

A randomised controlled trial comparing spontaneous healing, gelfoam patching and edge-approximation plus gelfoam patching in traumatic tympanic membrane perforation with inverted or everted edges

OBJECTIVE

To compare the outcome of patients with dry traumatic tympanic membrane perforation after spontaneous healing and gelfoam patching with or without perforation edge approximation.

DESIGN

Prospective clinical study.

SETTING

University-affiliated teaching hospital.

PARTICIPANTS

Ninety-one patients with acute dry traumatic tympanic membrane perforation inverted or everted edges were recruited. They were randomly allocated to three groups: spontaneous healing (n=31), gelfoam patching (n=30) and edge-approximation plus gelfoam patching (n=30). Otoscopy and tympanometry were performed before the treatment and at follow-up visits.

MAIN OUTCOME MEASURES

  Healing rate, healing time, ear infection rate and morphological changes during healing process.

RESULTS

The overall healing rate was 85% in the spontaneous healing group, lower than that in the two gelfoam patching groups (97%), but the difference failed to reach a statistical significance (P>0.05). The average healing time was 30 ± 10.1 days in the spontaneous healing group, significantly longer (P<0.01) than that in the other two groups (16 ± 5.6 and 18 ± 4.7 days, respectively). Middle ear infection rate did not differ significantly (7%, 3% and 3%, respectively). Spontaneous healing resulted in formation of scabs at the perforation edges, which was effectively prevented by gelfoam patching.

CONCLUSIONS

Gelfoam patching may facilitate healing of traumatically perforated tympanic membrane. Approximation of folded perforation edges is not necessary in gelfoam patching.

Middle Ear Injury through the External Auditory Canal: A Review of 44 Cases

We performed a retrospective review of 44 patients with middle ear injury incurred through the external auditory canal. Twenty-two of the 44 patients had presented to our center within 1 month of their injury (early group), and 22 presented later (delayed group); the mean interval from the time of the trauma to presentation was 6 days in the early group and 7 years in the delayed group. The causes of injury were penetrating trauma (70% of cases), thermal insults (20%), and explosive and nonexplosive blasts (9%). Purulent otorrhea, cholesteatoma, and ossicular discontinuity were more common in the delayed group. Otologic surgery was required in 9 early-group patients (41%) and in all 22 delayed-group patients (100%). Two patients in the early group developed a dead ear. The mean pure-tone averages (PTAs) at presentation were 30.7 and 52.2 dB in the early and delayed groups, respectively; after management, the corresponding mean PTAs were 21.0 and 42.5 dB. The respective mean air-bone gaps in the two groups were 14.6 and 28.2 dB at presentation and 8.0 and 17.2 dB after management. We conclude that middle ear injury incurred as a result of trauma sustained through the external auditory canal is associated with considerable morbidity. Patients who present in a delayed fashion have significantly poorer hearing at presentation and after management. Patients who do not develop a dead ear generally derive benefit from reconstruction of the middle ear sound-conduction mechanism.

Ear problems in swimmers

Acute diffuse otitis externa (swimmer's ear), otomycosis, exostoses, traumatic eardrum perforation, middle ear infection, and barotraumas of the inner ear are common problems in swimmers and people engaged in aqua activities. The most common ear problem in swimmers is acute diffuse otitis externa, with Pseudomonas aeruginosa being the most common pathogen. The symptoms are itching, otalgia, otorrhea, and conductive hearing loss. The treatment includes frequent cleansing of the ear canal, pain control, oral or topical medications, acidification of the ear canal, and control of predisposing factors. Swimming in polluted waters and ear-canal cleaning with cotton-tip applicators should be avoided. Exostoses are usually seen in people who swim in cold water and present with symptoms of accumulated debris, otorrhea and conductive hearing loss. The treatment for exostoses is transmeatal surgical removal of the tumors. Traumatic eardrum perforations may occur during water skiing or scuba diving and present with symptoms of hearing loss, otalgia, otorrhea, tinnitus and vertigo. Tympanoplasty might be needed if the perforations do not heal spontaneously. Patients with chronic otitis media with active drainage should avoid swimming, while patients who have undergone mastoidectomy and who have no cavity problems may swim. For children with ventilation tubes, surface swimming is safe in a clean, chlorinated swimming pool. Sudden sensorineural hearing loss and some degree of vertigo may occur after diving because of rupture of the round or oval window membrane.

Patterns of hearing loss in non-explosive blast injury of the ear

A prospective study of hearing loss in 120 cases with non-explosive blast injury of the ear, gathered over a six-year period, is presented. Thirty-three (27.5 per cent) patients had normal hearing, 57 (47.5 per cent) conductive hearing loss, 29 (24.2 per cent) mixed loss and one (0.8 per cent) had pure sensorineural loss. The severity of conductive hearing loss correlated with the size of the eardrum perforation; only a marginal difference was found between water and air pressure injuries, with respect to this type of hearing loss. Of all locations, perforations involving the posterior-inferior quadrant of the eardrum were associated with the largest air-bone gap. Audiometric assessment revealed that none of the patients suffered ossicular chain damage. Three patterns of sensorineural hearing loss were identified: a dip at a single frequency, two separate dips, and abnormality of bone conduction in several adjacent high frequencies. Involvement of several frequencies was associated with a more severe hearing loss than a dip in a single frequency. Healing of the perforation was always accompanied by closure of the air-bone gap, while the recovery of the sensorineural hearing loss was less favourable.

Extended high-frequency audiometry in traumatic tympanic membrane perforations

Air- and bone-conduction audiometry in the frequency ranges 0.125-18 kHz and 0.25-16 kHz respectively were performed in 38 patients with unilateral traumatic tympanic membrane perforation. Sensorineural threshold elevation was found in 16 ears. In nine of these this was permanent and in four restricted to the frequency range > 8 kHz. Both sensorineural threshold elevation and tinnitus (n = 16) diminished with time. A temporary, mean 5 dB, bone-conduction threshold elevation > or = 8 kHz was seen in 26 ears before spontaneous tympanic membrane closure. Closure resulted in a 7-20 dB improvement of air-conduction thresholds in the 0.125-18 kHz range, somewhat less in the upper than in the lower frequencies. A 3 dB mean final conductive hearing loss > 8 kHz was found in these 26 ears approximately 5 months after injury, probably due to scars in the pars tensa at the site of the former perforations. Thirty-seven of 38 perforations had healed at final follow-up examination.

Acoustic trauma caused by lightning

Lesions produced by exposure to noise are frequent in everyday life. Injuries may be found in all systems of the human body, from the digestive to the endocrine, from the cardiovascular to the nervous system. Many organs may be damaged, the ear being one of them. It is known that noise produced by factories, airports, musical instruments and even toys can cause auditory loss. Noises in nature can also cause acoustic trauma. This report is the case history of acoustic trauma caused by lightning. The patient was studied with CAT scan, electroencephalogram, and brain mapping, impedance audiometry with tympanogram and acoustic reflex, audiometry and evoked otoacoustics emissions: distortion products and transients.