Principal Component Analysis of Diffusion Tensor Images to Determine White Matter Injury Patterns Underlying Postconcussive Headache.

BACKGROUND AND PURPOSE: Principal component analysis, a data-reduction algorithm, generates a set of principal components that are independent, linear combinations of the original dataset. Our study sought to use principal component analysis of fractional anisotropy maps to identify white matter injury patterns that correlate with posttraumatic headache after mild traumatic brain injury. MATERIALS AND METHODS: Diffusion tensor imaging and neurocognitive testing with the Immediate Post-Concussion Assessment and Cognitive Test were performed in 40 patients with mild traumatic brain injury and 24 without posttraumatic headache. Principal component analysis of coregistered fractional anisotropy maps was performed. Regression analysis of the major principal components was used to identify those correlated with posttraumatic headache. Finally, each principal component that correlated with posttraumatic headache was screened against other postconcussive symptoms and demographic factors. RESULTS: Principal component 4 (mean, 7.1 ± 10.3) correlated with the presence of posttraumatic headache in mild traumatic brain injury (odds ratio per SD, 2.32; 95% CI, 1.29-4.67; P = .01). Decreasing principal component 4 corresponded with decreased fractional anisotropy in the midsplenium and increased fractional anisotropy in the genu of the corpus callosum. Principal component 4 identified patients with posttraumatic headache with an area under the receiver operating characteristic curve of 0.73 and uniquely correlated with posttraumatic headache and no other postconcussive symptom or demographic factors. CONCLUSIONS: Principal component analysis can be an effective data-mining method to identify white matter injury patterns on DTI that correlate with clinically relevant symptoms in mild traumatic brain injury. A pattern of reduced fractional anisotropy in the splenium and increased fractional anisotropy in the genu of the corpus callosum identified by principal component analysis can help identify patients at risk for posttraumatic headache after mild traumatic brain injury

Assessing Postconcussive Reaction Time Using Transport-Based Morphometry of Diffusion Tensor Images.

BACKGROUND AND PURPOSE: Cognitive deficits are among the most commonly reported post-concussive symptoms, yet the underlying microstructural injury is poorly understood. Our aim was to discover white matter injury underlying reaction time in mild traumatic brain injury DTI by applying transport-based morphometry. MATERIALS AND METHODS: In this retrospective study, we performed DTI on 64 postconcussive patients (10-28 years of age; 69% male, 31% female) between January 2006 and March 2013. We measured the reaction time percentile by using Immediate Post-Concussion Assessment and Cognitive Testing. Using the 3D transport-based morphometry technique we developed, we mined fractional anisotropy maps to extract the common microstructural injury associated with reaction time percentile in an automated manner. Permutation testing established statistical significance of the extracted injuries. We visualized the physical substrate responsible for reaction time through inverse transport-based morphometry transformation. RESULTS: The direction in the transport space most correlated with reaction time was significant after correcting for covariates of age, sex, and time from injury (Pearson CONCLUSIONS: Transport-based morphometry discovers complex white matter injury underlying postconcussive reaction time in an automated manner. The potential influences of edema and axonal loss are visualized in the visual-spatial interpretation and response-selection pathways. Transport-based morphometry can bridge the gap between brain microstructure and function in diseases in which the structural basis is unknown

Severe pigmented keratitis caused by Cladorrhinum bulbillosum

We report a case of severe pigmented keratitis with poor prognosis, caused by Cladorrhinum bulbillosum . Antifungal treatment with topical natamycin and fluconazole eye drops and oral tablet fluconazole failed to heal the ulcer and resulted in perforation. The causative fungus, C. bulbillosum, was identified on the basis of its typical microscopic features and 98% sequence homology to ex-type isolate CBS 304.90 (accession no. FM955448). The results of an in vitro antifungal susceptibility test indicated that the isolate was susceptible to natamycin, amphotericin B, fluconazole and itraconazole. The present case is the third case of keratitis and the second case of human keratitis. Compromised immunity due to liver cirrhosis could lead to a failed prognosis even when the fungal isolate is highly susceptible to antifungal treatment

Zebrafish twist2/dermo1 regulates scale shape and scale organization during skin development and regeneration

Scales are skin appendages in fishes that evolutionarily predate feathers in birds and hair in mammals. Zebrafish scales are dermal in origin and develop during metamorphosis. Understanding regulation of scale development in zebrafish offers an exciting possibility of unraveling how the mechanisms of skin appendage formation evolved in lower vertebrates and whether these mechanisms remained conserved in birds and mammals. Here we have investigated the expression and function of twist 2/dermo1 gene - known for its function in feather and hair formation - in scale development and regeneration. We show that of the four zebrafish twist paralogues, twist2/dermo1 and twist3 are expressed in the scale forming cells during scale development. Their expression is also upregulated during scale regeneration. Our knockout analysis reveals that twist2/dermo1 gene functions in the maintenance of the scale shape and organization during development as well as regeneration. We further show that the expression of twist2/dermo1 and twist3 is regulated by Wnt signaling. Our results demonstrate that the function of twist2/dermo1 in skin appendage formation, presumably under regulation of Wnt signaling, originated during evolution of basal vertebrates

sj-docx-1-han-10.1177_15589447231184894 – Supplemental material for Computed Tomography–Based Templating of Proximal Ulna Intramedullary Screw Fixation

Supplemental material, sj-docx-1-han-10.1177_15589447231184894 for Computed Tomography–Based Templating of Proximal Ulna Intramedullary Screw Fixation by Nitin Goyal, Dominic Coutinho, Anish Ghodadra, Mark E. Baratz and Robert A. Kaufmann in HAND</p

sj-jpg-2-han-10.1177_15589447231184894 – Supplemental material for Computed Tomography–Based Templating of Proximal Ulna Intramedullary Screw Fixation

Supplemental material, sj-jpg-2-han-10.1177_15589447231184894 for Computed Tomography–Based Templating of Proximal Ulna Intramedullary Screw Fixation by Nitin Goyal, Dominic Coutinho, Anish Ghodadra, Mark E. Baratz and Robert A. Kaufmann in HAND</p