Diffusion Tensor Imaging Detects Acute and Subacute Changes in Corpus Callosum in Blast-Induced Traumatic Brain Injury.

There is a critical need for understanding the progression of neuropathology in blast-induced traumatic brain injury using valid animal models to develop diagnostic approaches. In the present study, we used diffusion imaging and magnetic resonance (MR) morphometry to characterize axonal injury in white matter structures of the rat brain following a blast applied via blast tube to one side of the brain. Diffusion tensor imaging was performed on acute and subacute phases of pathology from which fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity were calculated for corpus callosum (CC), cingulum bundle, and fimbria. Ventricular volume and CC thickness were measured. Blast-injured rats showed temporally varying bilateral changes in diffusion metrics indicating persistent axonal pathology. Diffusion changes in the CC suggested vasogenic edema secondary to axonal injury in the acute phase. Axonal pathology persisted in the subacute phase marked by cytotoxic edema and demyelination which was confirmed by ultrastructural analysis. The evolution of pathology followed a different pattern in the cingulum bundle: axonal injury and demyelination in the acute phase followed by cytotoxic edema in the subacute phase. Spatially, structures close to midline were most affected. Changes in the genu were greater than in the body and splenium; the caudal cingulum bundle was more affected than the rostral cingulum. Thinning of CC and ventriculomegaly were greater only in the acute phase. Our results reveal the persistent nature of blast-induced axonal pathology and suggest that diffusion imaging may have potential for detecting the temporal evolution of blast injury.

Women Physicians and the Suffrage Movement.

Women physicians have a long history of advocacy, dating to the 19th century women's suffrage movement. As history recounts the work of the suffragists, many women physicians bear mention. Some were leaders on the national scene, and others led suffrage efforts in their own state. In this article, we provide a snapshot of 7 prominent suffragists who were also physicians: Mary Edwards Walker, Mary Putnam Jacobi, Esther Pohl Lovejoy, Marie Equi, Mattie E. Coleman, Cora Smith Eaton, and Caroline E. Spencer. In sharing their stories, we hope to better understand some of the challenges and struggles of the suffrage movement and how their advocacy paved the way not only for women's voting rights but also the role of women physicians as advocates for change.