1. Neuroimaging findings of Dive-related Decompression Sickness in Brain and Spine
Yeang Chng, Emmanuil Smorodinsky, Stellios Karnezis
Department of Radiology, University of California Los Angeles, Los Angeles, CA, United States, David Geffen School of Medicine at UCLA
Control #: 2866 Poster #: EE-42
Imaging Findings
MRI brain was remarkable for bilateral confluent subcortical white matter T2/FLAIR hyperintensity, predominantly in the perirolandic region, with subtle associated cortical restricted diffusion relative to normal brain (Figure 1). No hemorrhage or mass effect was seen.
MRI of the cervical and thoracic spine demonstrated patchy, long segment cervical and thoracic cord T2 hyperintensities predominantly involving the dorsal columns without cord expansion or hemorrhage (Figure 2).
Additionally, an air filled cavity containing T1 and T2 hyperintense fluid with layering areas of T2 hypointensity consistent with blood products was noted in the right upper lung apex (Figure 3), suggestive of a barotrauma related pneumatocele(5).
Summary
DCS occurs in divers during rapid ascent from depth, when dissolved nitrogen bubbles are released in tissues and blood stream more rapidly than can be safely eliminated through diffusion and perfusion processes, resulting in tissue damage (1). Clinically, DCS may be classified into mild forms (DCS I) and more severe, often life threatening form (DCS II), commonly affecting the brain, spinal cord, inner ear, and lungs (1). We demonstrate a case of type II DCS with a characteristic constellation of MR imaging findings in both the brain and spinal cord. The signal abnormalities in the perirolandic regions have been reported to be partially reversible in divers and high-altitude pilots (1,2). The spinal cord lesions, which preferentially affect white matter within the dorsal cord, have been attributed to higher regional fat content as a reservoir for dissolved nitrogen under pressure versus venous congestion/infarction (3,4). No hemorrhagic changes were seen, which has been associated with improved prognosis (1).
References
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Purpose
Demonstration of characteristic imaging findings associated with decompression sickness in both the spinal cord and brain in the same patient.
Case Report
We present a case of acute Type II decompression sickness (DCS) in a 22 year old female with bilateral upper and lower extremity weakness after scuba diving to a maximum depth of 107 ft for 22 minutes on air, with marked alteration of consciousness at 18 ft safety stop. The patient subsequently received hyperbaric chamber therapy and was airlifted to our institution with MRI performed ~10 hours subsequent to the incident. 1
Figure1. Bilateral confluent subcortical white matter T2 (D) and FLAIR (C) hyperintensity predominantly in the perirolandic region with subtle associated cortical restricted diffusion (A and B).
Figure 2. Sagittal and axial T2 images of the cervical (A and B) and thoracic (C and D) spine demonstrated patchy, long segment cervical and thoracic cord T2 hyperintensities predominantly involving the dorsal columns without cord expansion or hemorrhage.
Disclosures
The authors have no financial disclosures.
Figure 3. In the right lung apex, T1 (A) and T2 (B) images demonstrate air filled cavity containing T1 and T2 hyperintense fluid with layering areas of T2 hypointensity consistent with blood products, suggestive of a barotrauma related pneumatocele.