Abstract
Dear Editor,
We thank Dr. Lipman and his colleagues for his letter (Lipman et al., 2019).
My group and I pioneered the use of ultrasound in the field [first reporting on pulmonary, optic nerve sheath ultrasonography (ONSU) and inferior vena cava assays at altitude] to understand the pathophysiology of acute exposure to hypobaric hypoxia better. Given that we have used ultrasound to test hypotheses in populations, we can only be mystified when it is suggested that we have “overstated the utility of ultrasound for AMS [acute mountain sickness] management.” To be clear, we have great faith in the utility of ultrasound as a tool to elucidate fundamental central nervous system (CNS) pathophysiology in populations. We do not believe ONSU has any meaningful utility in the diagnosis or management of AMS for the individual patient.
We are pleased that the critical findings of our original 2009 ONSD study, the largest to date (N = 287), have been replicated. We are gratified that our pulmonary thoracic work has proven to be a portent, used globally for research and field care—but we remain agnostic about ultrasound except as it serves as a tool of discovery.
Our group's goal is to explore innovative techniques (not limited to ultrasonography, near infrared spectroscopy, advanced magnetic resonance imaging techniques, elastography, mitochondrial studies, discovery of novel CNS biomarkers, network analysis, etc.) to develop a syndromic diagnosis consisting of subjective and objective findings that better define the gross and molecular etiology of acute CNS pathophysiology caused by exposure to hypobaric hypoxia, a prospective diagnosis we call “high altitude cerebral illness” (HACI).
We are as welcoming of new collaborators as we are of new technologies.