Gregg and Bass 8 reported an EAE prevalence of 3% when examining excavated skulls from inland North American populations, whereas Kennedy 9 showed a 30% prevalence among civilizations known to frequently engage in cold-water activities. Several anthropological studies have tested the cold-water hypothesis by looking at various prehistoric populations. 2, 3 With few exceptions, previous clinical studies 1, 4 - 7 concentrated on the treatment outcomes and consequently were unable to estimate the prevalence of the disorder among persons at risk. 1 Although the cause of EAE has not been firmly established, it has nevertheless been clinically accepted that cold-water exposure is the initiation factor for temporal bone growth. New bone growth along the upper edges of the tympanic bone is believed to be the source of these diffuse hyperostotic elevations. They are recognized by otoscopic examination and characterized by 1 or more broad-based elevated lesions that protrude into the external auditory canal. Finally, the lesions seemed to affect all external auditory canal quadrants equally.Ĭonclusion A positive association exists between the amount of time individuals spend surfing and the presence and severity of exostoses of the external auditory canal.ĮXTERNAL auditory exostoses (EAE) are common in individuals who frequently participate in aquatic activities. In contrast, of surfers with severe exostoses, 82.4% had surfed for more than 10 years. Of surfers with no exostoses, 61.1% had surfed for 10 years or less. In comparison, in the group that had surfed for longer than 20 years, only 9.1% had normal auditory canals and 16.2% were severely affected. Of individuals who had surfed for 10 years or less, 44.7% had normal ear canals and only 6% had severely obstructed auditory canals. Of 441 ears with exostoses, 54.2% were mild, 23.6% were moderate, and 22.2% were severe.
Results There was a 73.5% overall prevalence of external auditory exostoses and a 19.2% overall prevalence of osteomas in the group studied. Grades of normal, mild, moderate, and severe corresponded to 100%, 99% to 66%, 65% to 33%, and less than 33% effective patent surface area, respectively. A simple grading system was devised, based on the degree of external auditory canal stenosis. Main Outcome Measures Questionnaires focusing on surfing habits (number of years, geographic region, and number of days per year of surfing) were correlated with otoscopic findings.
Patients Three hundred seven avid surfers (93.5% males and 6.5% females age distributions: 11.2% were ≤20, 67.9% were 21 to 40, 17.5% were 41 to 50, and 3.3% were >50 years). Objective To determine (1) the prevalence of external auditory exostoses in a population of surfers and (2) the relationship between the length of time spent surfing and the prevalence, severity, and location of the exostoses.ĭesign Cross-sectional epidemiological study. Shared Decision Making and Communication.Scientific Discovery and the Future of Medicine.Health Care Economics, Insurance, Payment.Clinical Implications of Basic Neuroscience.Challenges in Clinical Electrocardiography.