For many divers, the ocean's depths hold both mystery and wonder.

But within that beauty lies a physical danger often underestimated: barotrauma to the ears.

This pressure-related injury doesn't just cause temporary discomfort — it can lead to serious and sometimes irreversible damage if not understood and managed properly. Today's letter delves deeper into the anatomy, mechanisms, and evolving treatments of ear barotrauma in divers, supported by expert insight and up-to-date science.

Understanding Barotrauma: When Pressure Turns Against the Body

Barotrauma refers to tissue injury caused by a pressure difference between an air-filled space in the body and the surrounding environment. For divers, the middle ear is particularly vulnerable. As descent begins, external pressure increases rapidly. If the diver fails to equalize this pressure through the Eustachian tube, negative pressure builds inside the middle ear, pulling on the eardrum and potentially leading to inflammation, rupture, or hemorrhage.

This specific form of injury — middle ear barotrauma (MEB) — is the most common diving-related medical issue. According to a 2023 clinical review published in Undersea and Hyperbaric Medicine Journal, up to 40% of novice divers report symptoms of ear barotrauma during their initial training dives.

The Mechanics of Injury: From Fluid Shift to Rupture

The most immediate effect of unequal pressure is discomfort or pain. However, more severe outcomes occur with deeper dives or repeated exposure. When the pressure differential exceeds 5 psi, small capillaries within the middle ear can rupture, leading to serious, known as hemotympanum. If pressure continues to build without successful equalization, tympanic membrane perforation can occur, allowing water to enter the middle ear and severely impacting hearing and balance.

Dr. Elise Tanaka, an otolaryngologist specializing in dive medicine, notes: "The eardrum is not as resilient as many assume. Even a shallow dive with improper equalization can create enough force to tear the membrane or disrupt the ossicular chain."

Inner Ear Involvement: When Symptoms Turn Severe

Though less common, inner ear barotrauma (IEB) represents a more serious condition. It usually results from forceful Valsalva maneuvers during descent or ascent, leading to perilymph fistulas or damage to the cochlear and vestibular structures. Symptoms may include sudden sensorineural hearing loss, tinnitus, vertigo, or imbalance — often occurring without pain.

Unlike MEB, inner ear barotrauma demands urgent evaluation, ideally with audiometry and high-resolution MRI to rule out other neurological causes. Early surgical repair may be indicated if perilymph leakage is suspected, although conservative treatment using steroids and rest remains standard for mild cases.

Diagnosing Ear Barotrauma: Not All Damage Is Visible

Physical examination with otoscopy remains the frontline tool, but early barotrauma can be subtle. Physicians should look for retracted eardrums, fluid levels, or ecchymosis behind the tympanic membrane. In more advanced cases, tympanometry and pure-tone audiometry can document conductive hearing loss due to fluid or perforation. For inner ear involvement, videonystagmography (VNG) and vestibular testing are essential.

Modern diagnostic algorithms now also incorporate patient-reported outcomes, as many divers may downplay symptoms. Educating divers to report even transient symptoms like muffled hearing or popping sounds is crucial in preventing progression.

Prevention: Skill, Education, and Equipment Matter

Preventing barotrauma isn't just about luck — it's about knowledge and habit. Proper equalization techniques, such as the Frenzel maneuver or Toynbee method, can be more effective and gentler than Valsalva. Divers should avoid descending while congested, as sinus inflammation can obstruct the Eustachian tubes.

Using vented ear plugs and diving slowly during descent are recommended, especially for new divers. Dive instructors should emphasize ear safety as part of foundational training, not just as an afterthought. Additionally, advancements in underwater communication masks and smart dive computers are being explored for real-time pressure feedback, allowing divers to better manage their exposure and depth adjustments.

Treatment and Recovery: Healing Time and Hearing Preservation

The majority of middle ear barotrauma cases resolve spontaneously within 7–10 days, provided there's no infection or repeated exposure. Decongestants, nasal corticosteroids, and avoidance of diving until full recovery are commonly prescribed. Antibiotic drops may be indicated if water enters the middle ear through a perforation.

For persistent perforations or ossicular disruption, tympanoplasty or ossiculoplasty may be necessary. In inner ear injuries, hearing loss may be permanent if not addressed quickly, especially within the first 72 hours. Steroid therapy and vestibular rehabilitation can aid recovery but require specialist oversight.

Barotrauma may be invisible, but for divers, its consequences can echo long after surfacing. With greater awareness, precise diagnosis, and evidence-based prevention, ear injuries need not be a routine hazard of underwater exploration. By understanding the delicate interplay of pressure and anatomy, divers and clinicians alike can ensure that the thrill of the deep does not come at the cost of hearing or balance.