Tympanic Membrane Perforation

Definition and epidemiology

A tympanic membrane perforation is a break in the integrity of the eardrum, in other words a hole in it. Perforations fall into two broad groups. Traumatic perforations follow objects pushed into the canal, sudden pressure changes such as a slap or a nearby blast, diving and water sports, barotrauma, head injury, and procedures such as ear syringing. Infective perforations occur when pus building up in acute otitis media ruptures the drum; a hole that fails to heal and keeps discharging is the central feature of chronic otitis media. By position, a central perforation, with a rim of drum all around it, is distinguished from a marginal perforation that reaches the bony ring (annulus); size is described as a percentage of the drum surface or by the number of quadrants involved.

In United States emergency departments, 61.2% of traumatic perforations are caused by objects inserted into the ear canal, cotton buds being the leading culprit, and roughly two thirds of patients are under 18 (Carniol et al., 2018). In a study of 1003 ears with chronic perforations, 63.5% showed no sign of previous retraction; in these ears 99% of perforations were central and the mean perforation area was 18.5% of the drum surface (Selaimen et al., 2022).

Symptoms and signs

The typical picture of a traumatic perforation is sudden earache (otalgia), reduced hearing and bloody discharge (otorrhoea), sometimes with tinnitus (Harvie et al., 2024). The pain usually eases quickly. In acute otitis media, by contrast, severe pain suddenly settles when the drum ruptures and purulent discharge follows. A chronic perforation is usually painless; people mainly report recurrent discharge, often after water gets into the ear or after a cold, and a variable degree of hearing loss.

Otoscopy assesses the site, size and edges of the hole and, where visible, the middle ear mucosa. A fresh traumatic perforation has ragged, blood-stained edges, whereas a chronic one has a smooth, rounded margin. A marginal site, skin growing in from the edge or white keratin debris should raise concern about cholesteatoma. After an injury, vertigo, facial palsy, lateralisation of the tuning fork to the good ear or severe hearing loss are red flags for inner ear or ossicular damage and call for early ENT assessment (Harvie et al., 2024).

Causes and risk factors

The eardrum is thin and flexible. Cotton buds, hairpins, combs and similar objects can puncture it directly; in emergency department data cotton buds are the leading cause in every age group except 13-36 years, where water-related injuries come first (Carniol et al., 2018). An open-handed slap over the ear and a nearby explosion send a sudden pressure wave down the canal, and diving and water sports are well-recognised causes (Harvie et al., 2024). Procedures such as syringing or removal of a foreign body or wax can also perforate the drum.

In infective perforation, pressure from pus in the middle ear and inflammatory thinning of the drum cause it to rupture. The hole often closes once the infection settles; if it does not and infections keep recurring, chronic otitis media develops. In the 1003-ear series, ears with signs of previous retraction had larger perforations (mean area 41.4% versus 18.5%), a wider mean air-bone gap (29.2 dB versus 23.9 dB) and more often an abnormal opposite ear (66% versus 28%). The authors suggested that in this group the perforation may be the end result of long-standing retraction (Selaimen et al., 2022), a process described under adhesive otitis media and retraction pockets.

Audiological and clinical assessment

The diagnosis is made by otoscopy or otomicroscopy. Syringing is avoided after a traumatic perforation because it can carry infection into the middle ear (Harvie et al., 2024). Audiological assessment documents the degree and type of loss, looks for ossicular or inner ear damage and tracks recovery.

• Pure-tone audiometry: a mild conductive loss with normal bone conduction is expected. In 62 perforated ears without other middle ear disease, the air-bone gap was largest at low frequencies, narrowed as frequency rose and grew with perforation size. Ears with a middle ear and mastoid air volume of 4.3 ml or less had gaps on average 10-20 dB wider, and anterior and posterior perforations did not differ significantly (Mehta et al., 2006).
• An unexpectedly large air-bone gap: if the loss is too large to be explained by the size of the hole, an additional problem such as ossicular discontinuity or fixation is sought (ossicular chain discontinuity). A drop in bone-conduction thresholds may mean that the injury has reached the inner ear; bone conduction should be confirmed with appropriate masking.
• Tympanometry: with no intact membrane the trace is flat (type B), and because the middle ear and mastoid air space are added to the measured volume, the ear canal volume is larger than expected for age. In 334 children aged 6 weeks to 6.7 years, an equivalent ear canal volume of 1.0 cm³ or more identified a perforation with the lowest error rate, with some overlap below the age of 4 (Shanks et al., 1992). With a very small hole, or swollen or fluid-filled middle ear mucosa, the volume may not be clearly raised.
• Acoustic reflexes: no reflex can be recorded with the probe in the perforated ear, which must be borne in mind when reading the reflex pattern.
• OAEs: responses may be reduced or absent because of the conductive component, so their absence says little about cochlear function on its own.
• Follow-up audiogram: audiometry about three months after a traumatic perforation is recommended to confirm recovery (Harvie et al., 2024).

When a tympanogram is flat, the volume reading is decisive; the table below summarises the three possibilities. In the differential diagnosis, a deep retraction pocket or an atelectatic drum can look like a hole on otoscopy, but the volume is normal because the membrane is intact. A perforation that keeps discharging, smells offensive or is marginal should prompt exclusion of cholesteatoma.

Treatment and audiological rehabilitation

Most traumatic perforations close on their own. In Denmark, 97% of 137 traumatic perforations managed by watchful waiting closed, 81% of them within three months; size was the only significant determinant of healing time, and holes smaller than a quarter of the drum were very likely to close within 3-4 weeks (Jellinge et al., 2015). In another study, 72% of perforations smaller than a quarter of the drum healed within a month, against 25% of larger ones (Harvie et al., 2024). In a Turkish series of 80 patients, the closure rate was 81.6% with spontaneous healing and 95.2% with paper patching in the first week, a difference that was not statistically significant (Hanege et al., 2018).

During follow-up the ear is kept dry, using a cotton ball coated in petroleum jelly in the shower and a silicone earplug for bathing and swimming. If discharge becomes purulent the doctor may start topical treatment, and potentially ototoxic drops are avoided when the drum is perforated. Referral to ENT is needed if the perforation persists at three months, if discharge continues despite two weeks of topical treatment, or if there is severe hearing loss, vertigo or facial weakness (Harvie et al., 2024). The choice of medicine and procedure rests with the doctor.

A persistent or chronic perforation is repaired by tympanoplasty; repair of the drum alone is called type I tympanoplasty or myringoplasty, usually with temporalis fascia or cartilage as the graft. A meta-analysis of 214 studies and 26,097 patients found a closure rate of 86.6% at 12 months. Failure was 5.8% more frequent in children than in adults, perforations smaller than half the drum closed 6.1% more often, and cartilage improved closure by 2.8% compared with fascia, while a dry ear at surgery, the site of the perforation within the pars tensa and the surgical approach made no significant difference (Tan et al., 2016). A meta-analysis of 2609 paediatric cases from 45 studies reported a closure rate of 83.4%; larger perforations and an abnormal opposite ear were linked to failure, and age had no significant effect (Hardman et al., 2015).

Accurate, properly masked bone-conduction thresholds before and after surgery provide the baseline for judging any hearing gain. If no surgery is planned or the hole does not close and the loss is troublesome, a hearing aid can be fitted. An occluding earmould raises humidity and may trigger discharge, so a widely vented or open fitting is preferred; with persistent discharge, bone conduction implants can be considered with the surgeon. If an ear impression is needed with a perforated drum, the canal block must be placed carefully so that impression material cannot reach the middle ear.

Impact on quality of life and advice

As most traumatic perforations close within weeks, long-term effects are usually limited; the main concern meanwhile is keeping water out of the ear. With a chronic perforation, swimming, bathing and water sports need planning, and water entering the ear can set off episodes of discharge. For children, participation in school swimming lessons is arranged on medical advice. A mild unilateral conductive loss can make listening harder in noise and when the speaker is on the affected side; in class, sitting with the better ear towards the teacher helps.

Practical advice: do not clean your ears with cotton buds, hairpins or similar objects. Until the hole has closed, use a cotton ball with petroleum jelly in the shower and a silicone plug for swimming, and do not use ear drops your doctor has not prescribed. Wear hearing protection where there is a risk of blasts or loud noise. A slap over the ear can cause serious injury; after such an injury, do not skip a hearing check. If you plan to dive or spend long periods in water, ask your doctor first. After surgery, follow your surgeon’s schedule for check-up audiograms and water precautions.