776 research outputs found

    \u3cem\u3eEx Vivo\u3c/em\u3e Diffusion Tensor Imaging of Spinal Cord Injury in Rats of Varying Degrees of Severity

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    The aim of this study was to characterize magnetic resonance diffusion tensor imaging (DTI) in proximal regions of the spinal cord following a thoracic spinal cord injury (SCI). Sprague–Dawley rats (n = 40) were administered a control, mild, moderate, or severe contusion injury at the T8 vertebral level. Six direction diffusion weighted images (DWIs) were collected ex vivo along the length of the spinal cord, with an echo/repetition time of 31.6 ms/14 sec and b = 500 sec/mm2. Diffusion metrics were correlated to hindlimb motor function. Significant differences were found for whole cord region of interest (ROI) drawings for fractional anisotropy (FA), mean diffusivity (MD), longitudinal diffusion coefficient (LD), and radial diffusion coefficient (RD) at each of the cervical levels ( p \u3c 0.01). Motor function correlated with MD in the cervical segments of the spinal cord (r2 = 0.80). The diffusivity of water significantly decreased throughout ‘‘uninjured’’ portions of the spinal cord following a contusion injury ( p \u3c 0.05). Diffusivity metrics were found to be altered following SCI in both white and gray matter regions. Injury severity was associated with diffusion changes over the entire length of the cord. This study demonstrates that DTI is sensitive to SCI in regions remote from injury, suggesting that the diffusion metrics may be used as a biomarker for severity of injury

    Diffusion Imaging in the Rat Cervical Spinal Cord

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    Magnetic resonance imaging (MRI) is the state of the art approach for assessing the status of the spinal cord noninvasively, and can be used as a diagnostic and prognostic tool in cases of disease or injury. Diffusion weighted imaging (DWI), is sensitive to the thermal motion of water molecules and allows for inferences of tissue microstructure. This report describes a protocol to acquire and analyze DWI of the rat cervical spinal cord on a small-bore animal system. It demonstrates an imaging setup for the live anesthetized animal and recommends a DWI acquisition protocol for high-quality imaging, which includes stabilization of the cord and control of respiratory motion. Measurements with diffusion weighting along different directions and magnitudes (b-values) are used. Finally, several mathematical models of the resulting signal are used to derive maps of the diffusion processes within the spinal cord tissue that provide insight into the normal cord and can be used to monitor injury or disease processes noninvasively. The video component of this article can be found at http://www.jove.com/video/52390/ Introduction Magneti

    Severity of Spinal Cord Injury Influences Diffusion Tensor Imaging of the Brain

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    Background: The purpose of this study was to determine whether DTI changes in the brain induced by a thoracic spinal cord injury are sensitive to varying severity of spinal contusion in rats. Methods: A control, mild, moderate, or severe contusion injury was administered over the eighth thoracic vertebral level in 32 Sprague-Dawley rats. At 11 weeks postinjury, ex vivo DTI of the brain was performed on a 9.4T Bruker scanner using a pulsed gradient spin-echo sequence. Results: Mean water diffusion in the internal capsule regions of the brain and pyramid locations of the brainstem were correlated with motor function (r2 = 0.55). Additionally, there were significant differences between injury severity groups for mean diffusivity and fractional anisotropy at regions associated with the corticospinal tract (P = 0.05). Conclusion: These results indicate that DTI is sensitive to changes in brain tissue as a consequence of thoracic SCI

    Clinical Correlates of High Cervical Fractional Anisotropy in Acute Cervical Spinal Cord Injury

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    Objective: Fractional anisotropy (FA) of the high cervical cord (C1-C2), rostral to the injury site, correlates with upper limb function in patients with chronic cervical spinal cord injury (SCI). In acute cervical SCI, this relationship has not been investigated. The objective of this study was to identify functional correlates of FA of the high cervical cord in a series of patients with acute cervical SCI. Methods: Traumatic cervical SCI patients who underwent presurgical cervical spine diffusion tensor imaging at our institution were reviewed for this study. FA of the whole cord as well as the lateralcorticospinal tracts (CSTs) was calculated on axial images from C1-C2. Upper limb motor (C5-T1) and sensory (C2-T1) function scores were extracted from the admission American Spinal Injury Association (ASIA) examinations. Correlation analysis for FA with ASIA examinations was performed using a Pearson correlation. Results: Twelve subjects (9 men, 3 women; mean age 54.7 ± 4.0 years) underwent cervical spine diffusion tensor imaging at a mean duration of 3.6 ± 0.9 days postinjury. No patient had cord compression or intramedullary T2-weighted hyperintensities within the C1-C2 segments. FA correlated with upper limb motor score (whole cord: r = 0.59, P = .04; CST: 0.67, P = .01) and the ASIA grade (whole cord: r = 0.61, P = .03; CST: r = 0.71, P = .009). No correlation was found between FA and sensory scores. Conclusions: FA of the whole cervical cord as well as the CST, rostral to the injury site, is associated with preserved upper limb motor function as well as superior ASIA grades after acute cervical SCI. FA of the high cervical cord is a potential biomarker of neural injury after acute cervical SCI

    Robotic-Assisted Systems for Spinal Surgery

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    Robotic-assisted spinal surgery is in its infancy. It aims to improve the accuracy of screw placement, lower the risk of surgical complications, and reduce radiation exposure to the patient and the surgical team. The present chapter attempts to provide an overview of the evolution of robotic-assisted spinal surgery and highlights different commercially available spine robotic systems in present use. The review concludes with future applications of robotics in spinal surgery

    The common and uncommon cestodal infestation encountered in routine histopathological practice from a semi-urban population in south India and their public health importance.

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    Parasites are encountered uncommonly in routine histopathologic practice. Among them, cestodes form a major bulk. Cysticercosis heads the list forming the bulk of cases followed by Hydatidosis and Sparganosis. Microscopic identification of inflammation with surrounding reactions along with other morphological features forms the mainstay of diagnosis of parasitic diseases on histopathology. Identification of the parasites on histopathological examination would reduce the cost-diagnosis ratio avoiding expensive serological investigation

    Diffusion Tensor Imaging Correlates with Short-Term Myelopathy Outcome in Patients with Cervical Spondylotic Myelopathy

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    Objective To determine if spinal cord diffusion tensor imaging indexes correlate with short-term clinical outcome in patients undergoing elective cervical spine surgery for cervical spondylotic myelopathy (CSM). Methods A prospective consecutive cohort study was performed in patients undergoing elective cervical spine surgery for CSM. After obtaining informed consent, patients with CSM underwent preoperative T2-weighted magnetic resonance imaging and diffusion tensor imaging of the cervical spine. Fractional anisotropy (FA) values at the level of maximum cord compression and at the noncompressed C1-2 level were calculated on axial images. We recorded the modified Japanese Orthopaedic Association (mJOA) scale, Neck Disability Index, and Short Form-36 physical functioning subscale scores for all patients preoperatively and 3 months postoperatively. Statistical analysis was performed to identify correlations between FA and clinical outcome scores. Results The study included 27 patients (mean age 54.5 years ± 1.9, 12 men). The mean postoperative changes in mJOA scale, Neck Disability Index, and Short Form-36 physical functioning subscale scores were 0.9 ± 0.3, −6.0 ± 1.9, and 3.4 ± 1.9. The mean FA at the level of maximum compression was significantly lower than the mean FA at the C1-2 level (0.5 vs. 0.55, P = 0.01). FA was significantly correlated with change in mJOA scale score (Pearson r = −0.42, P = 0.02). FA was significantly correlated with the preoperative mJOA scale score (Pearson r = 0.65, P \u3c 0.001). Conclusions Preoperative FA at the level of maximum cord compression significantly correlates with the 3-month change in mJOA scale score among patients with CSM. FA was also significantly associated with preoperative mJOA scale score and is a potential biomarker for spinal cord dysfunction in CSM

    Serum calcium 125 level in normotensive and pre-eclamptic pregnancies in a tertiary care hospital

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    Background: Preeclampsia is one main reason for high-risk pregnancy. Among the disorders in hypertension, preeclampsia develops in antenatal period and it is defined by high blood pressure of more than 140/90 mmHg and arteriolar vasoconstriction, both of which lower uteroplacental perfusion and ultimately lead to placental hypoxia. The objectives of this study was (a) to estimate CA125 level in normotensive and pre eclamptic pregnancies; and (b) to predict severity of pre-eclampsia with CA125 levels with cut off value of CA125 level as 23.7 IU/ml. Methods: This two year cross sectional study was conducted on all antenatal mothers bestween 20 -40 weeks gestational age getting admitted RLJH and research centre Tamaka (January 2021-December 2022), for the period of 2 years who fulfilled inclusion and exclusion criteria. Detailed clinical history along with antenatal examination was done. For each study subject the blood pressure was recorded. Complete blood picture was done and CA125 levels were done of the study subjects. Results: Mean CA125 among normal subjects was 24.24±13.71 IU/ml and Mean CA125 among pre-eclampsia subjects was 30.61±15.69 IU/ml. There was a statistical significance found between two groups with respect to CA125. Conclusions: In pre-eclampsia, CA125 was increased more compared to normotensive group. This indicates the importance in estimation of CA125 level in preeclampsia. The same has been determined with significant p value

    Optimizing Filter-Probe Diffusion Weighting in the Rat Spinal Cord for Human Translation

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    Diffusion tensor imaging (DTI) is a promising biomarker of spinal cord injury (SCI). In the acute aftermath, DTI in SCI animal models consistently demonstrates high sensitivity and prognostic performance, yet translation of DTI to acute human SCI has been limited. In addition to technical challenges, interpretation of the resulting metrics is ambiguous, with contributions in the acute setting from both axonal injury and edema. Novel diffusion MRI acquisition strategies such as double diffusion encoding (DDE) have recently enabled detection of features not available with DTI or similar methods. In this work, we perform a systematic optimization of DDE using simulations and an in vivo rat model of SCI and subsequently implement the protocol to the healthy human spinal cord. First, two complementary DDE approaches were evaluated using an orientationally invariant or a filter-probe diffusion encoding approach. While the two methods were similar in their ability to detect acute SCI, the filter-probe DDE approach had greater predictive power for functional outcomes. Next, the filter-probe DDE was compared to an analogous single diffusion encoding (SDE) approach, with the results indicating that in the spinal cord, SDE provides similar contrast with improved signal to noise. In the SCI rat model, the filter-probe SDE scheme was coupled with a reduced field of view (rFOV) excitation, and the results demonstrate high quality maps of the spinal cord without contamination from edema and cerebrospinal fluid, thereby providing high sensitivity to injury severity. The optimized protocol was demonstrated in the healthy human spinal cord using the commercially-available diffusion MRI sequence with modifications only to the diffusion encoding directions. Maps of axial diffusivity devoid of CSF partial volume effects were obtained in a clinically feasible imaging time with a straightforward analysis and variability comparable to axial diffusivity derived from DTI. Overall, the results and optimizations describe a protocol that mitigates several difficulties with DTI of the spinal cord. Detection of acute axonal damage in the injured or diseased spinal cord will benefit the optimized filter-probe diffusion MRI protocol outlined here

    Breastfeeding Practices and Dietary Diversity among Infants and Young Children in Rural and Urban-Slum Populations in India: An Observational Study

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    Background: Nutritional exposures and growth in early life are linked to immediate and also to long term health outcomes. Objective: To assess infant and young child feeding (IYCF) practices using WHO-UNICEF defined indicators in rural and urban-slum populations in India. Methods: A community-based, cross-sectional study was conducted in mothers and infants up to age 24 months. Data on socio-demographics, birth history, feeding practices (WHO-UNICEF IYCF indicators), maternal weight, height, and infant’s weight, length, mid-arm, and head circumferences were collected. Results: Five hundred and two (252 rural and 250 urban-slum) mother-infant dyads were studied. Proportions of IYCF indicators in rural and urban-slum infants were: Early initiation of breastfeeding 71 and 64%; Exclusive breastfeeding under six months, 59 and 25%; Minimum acceptable diet 11 and 27% respectively. Consumption of animal-source food (other than dairy products) and vitamin-A rich fruits and vegetables was below 15%. Cesarean section [aOR, 95% CI: 2.94 (1.53, 5.65)], hospitalization of newborn [aOR, 95% CI: 6.21 (2.95, 13.16)], pre-lacteal feeding [aOR, 95% CI: 3.38 (1.77, 6.45)], needing help in breastfeeding [aOR, 95% CI: 2.15 (1.04, 4.17)], and male gender [aOR, 95% CI: 2.13 (1.15, 4.25); p<0.05 for all] were associated with delayed initiation of breastfeeding, whereas lower monthly household income [aOR, 95% CI: 2.62 (1.10, 6.25)], and younger age [aOR, 95% CI: 1.24 (1.11, 1.38); p<0.05 for both] were associated with poor dietary diversity. Conclusions: Education of optimum IYCF practices, targeting early initiation of breastfeeding, increasing meal frequency and intake of vitamin-A rich and animal-source foods need urgent attention
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