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Categorization of PLF used in Japan.
| Category 1: linked to trauma, middle and inner ear diseases, middle, and/or inner ear surgeries Category 2: linked to barotrauma caused by antecedent events of external origin (such as flying or diving) Category 3: linked to barotrauma caused by antecedent events of internal origin (such as straining, sneezing, or coughing) Category 4: has no apparent antecedent event |
