A 15-year-old man presented with stupor following a motorcycle traffic accident. The patient was diagnosed with a traumatic left carotid cavernous fistula (CCF) with pseudoaneurysm of the left internal carotid artery. Brain magnetic resonance imaging (MRI) showed transiently restricted diffusion in the left centrum semiovale white matter and lower temporo-occipital area extending to the splenium of the corpus callosum, with high signal intensity on diffusion-weighted imaging. On the 35th day of admission, the patient had complete neurological recovery and a follow-up brain MRI revealed complete resolution of the lesions in the left centrum semiovale and splenium of the corpus callosum. These clinical and radiological features are highly suggestive of complete reversal of diffusion restriction after successful embolization of traumatic CCF.
Accidents, Traffic ; Adolescent ; Aneurysm, False ; Brain ; Carotid Artery, Internal ; Corpus Callosum ; Diffusion* ; Fistula* ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Motorcycles ; Stupor ; White Matter

The expansion of allergen-specific CD4⁺ T cells is a critical step in inducing airway inflammation during allergic asthma. Such clonal expansion of T cells is initiated through the interaction between allergen-bearing dendritic cells and allergen-specific naïve T cells in the draining lymph nodes. Whether such T cell clonal expansion also occurs in the lung, the primary organ encountering inhaled allergens, remains unclear. Compared with wild-type mice, we found similar frequencies of CD4⁺ T cells in the lung of lymph node-deficient Rorgt(gfp/gfp) mice after repeated exposure to inhaled allergens. In addition, we observed an evident population of CD4⁺ T cells that underwent clonal expansion in the lung of allergen-challenged mice treated with an S1P antagonist FTY720 in an in vivo proliferation study with CFSE-labeled OT-II T cells. Moreover, the expansion of allergen-specific CD4⁺ T cells was significantly enhanced in the lungs of Rorgt(gfp/gfp) mice in comparison to that of wild-type mice. These results together demonstrate that the clonal expansion of allergen-specific CD4⁺ T cells occurs in the absence of the lymph nodes, indicating that the lung can act as a primary site of the clonal expansion of CD4⁺ T cells in response to inhaled allergens.
Allergens ; Animals ; Asthma ; Dendritic Cells ; Fingolimod Hydrochloride ; Inflammation ; Lung* ; Lymph Nodes* ; Mice ; T-Lymphocytes