Superficial Temporal Artery Aneurysm in a Helicopter Pilot Operating at High Altitude

BACKGROUND: Spontaneous aneurysm of the superficial temporal artery in a helicopter pilot while operating in the extreme cold climatic conditions of a very high altitude area led to a thorough search for etiological possibilities related to this case.CASE REPORT: A 38-yr-old military helicopter pilot, while flying at altitudes ranging from 4500 m to 6000 m (15,000 to 20,000 ft) reported with an acute onset of a subcutaneous swelling on his left temple. History and clinical profile did not suggest any traumatic, hematologic, or vasculitic etiology. His inflammatory markers, anti-nuclear antibody, anti-neutrophil cytoplasmic antibodies, complement levels, and whole-body PET scan did not suggest any evidence of vasculitis. Presence of any other intracranial aneurysms was also ruled out. He underwent curative excision biopsy, which showed perivascular inflammation. He was diagnosed as a case of left superficial temporal artery aneurysm. The recovery period was uneventful and the follow-up color Doppler flow imaging of the temporal artery and acute phase reactants was normal.DISCUSSION: Spontaneous aneurysms involving the superficial temporal artery is a very rare diagnosis. Occurrence of such an aneurysm in a young pilot without any identifiable predisposing factors led the authors to hypothesize a possible etiological combination of environmental and mechanical factors along with aviation stresses with the likely compounding role of the helmet. Management and aeromedical aspects of this unique case are discussed in this paper.Sekhar BM, Sheoran S, Routh D, Sharma S.