Terson’s syndrome: an important differential diagnosis of subarachnoid hemorrhage

1. Santa Casa de Montes Claros, Montes Claros, MG, Brazil. 2. Universidade Federal do Triângulo Mineiro (UFTM), Uberaba, MG, Brazil. Mailing address: Dr. Dimitrius Nikolaos Jaconi Stamoulis. Departamento de Radiologia e Diagnóstico por Imagem – UFTM. Avenida Getúlio Guaritá, 130, Nossa Senhora da Abadia. Uberaba, MG, Brazil, 38025-250. E-mail: dimitriusss@hotmail. com. Known triggers include acute exacerbation of asthma and situations requiring the Valsava maneuver. The combination of spontaneous pneumomediastinum and pneumorrhachis is extremely rare. Possible causes of pneumorrhachis include use of the drug ecstasy, abscesses, asthma attacks, coughing fits, violent vomiting, epidural anesthesia, lumbar puncture, and thoracic or vertebral surgery or trauma. In extremely rare cases, meningitis or pneumocephalus can occur. Pneumorrhachis typically occurs directly, when atmospheric air reaches the epidural space by means of a needle or a penetrating wound from the spine, although it can occur indirectly, as in bronchial asthma. In the case of bronchial asthma, air from the rupture of a peripheral pulmonary alveolus leaks into the pulmonary perivascular interstitium and follows the path of least resistance of the mediastinum to the fascia of the neck. Due to the absence of fascial barriers, air crosses the neural foramen and deposits in the epidural space. In either situation, pneumorrhachis is usually asymptomatic and disappears spontaneously within a few weeks. Whereas CT allows direct visualization of the presence of air in the affected compartment(s), X-rays can reveal signs typical of pneumomediastinum, produced when the air leaving the mediastinum delineates the normal anatomical structures. Such signs include subcutaneous emphysema, the “sail sign” of the thymus, pneumopericardium, the “ring-around-the-artery” sign, the “continuous diaphragm” sign, and the “double bronchial wall” sign. REFERENCES