Return to Work Within Four Months of Grade 3 Diffuse Axonal Injury

Neuroprognostication following diffuse axonal injury (DAI) has historically relied on neuroimaging techniques with lower spatial resolution and contrast than techniques currently available in clinical practice. Since the initial studies of DAI classification and prognosis in the 1980s and 1990s, advances in neuroimaging have improved detection of brainstem microbleeds, a hallmark feature of Grade 3 DAI that has traditionally been associated with poor neurologic outcome. Here, we report clinical and radiologic data from two patients with severe traumatic brain injury and grade 3 DAI who recovered functional independence and returned to work within 4 months of injury. Importantly, both patients were scanned using 3 Tesla MRI protocols that included susceptibility-weighted imaging (SWI), a technique that provides enhanced sensitivity for detecting brainstem microbleeds. These observations highlight the importance of developing approaches to DAI classification and prognosis that better align with contemporary neuroimaging capabilities.

An Anatomic Study of the Sural Nerve Using 3-Tesla MRI: A Comparison to Cadaveric Data With Surgical Applications

Background: The sural nerve (SN) is a sensory cutaneous nerve that is at risk of iatrogenic injury during surgery at the lateral ankle. Prior anatomic studies of the SN are limited primarily to cadaveric studies with small sample sizes. Our study analyzed a large cohort of magnetic resonance images (MRIs) of the ankle to obtain a more generalizable, in vivo sample of distal SN course. Methods: A total of 204 3-tesla MRI studies of the ankle were analyzed. Three reviewers measured the distance from the SN to various landmarks including the distal tip of the lateral malleolus (DTLM) and the lateral border of the Achilles tendon (LBA). Results: Mean vertical distance from SN to DTLM was 2.2 cm (range, 0.9-3.6 cm). Mean horizontal distance from SN to DTLM and to LBA at the level of DTLM was 1.7 cm (range, 0.8-3.0 cm) and 1.9 cm (range, 1.0-2.9 cm), respectively. Mean horizontal distance from SN to LBA at the level of superior Achilles tendon insertion onto the calcaneus (SAI) was 2.6 cm (range, 1.4-3.7 cm), and mean horizontal distance from SN to LBA at 5 cm above SAI was 0.9 cm (range, 0.4-1.8 cm). Conclusion: The variation in SN course observed in our study allowed us to propose “safe zones” for several surgical approaches including the extensile lateral approach to the calcaneus (ELAC), the sinus tarsi approach (STA), the direct lateral approach to the lateral malleolus (DLA), and the posterolateral approach to the ankle (PLA), which we hope will minimize iatrogenic injury to the SN. Level of Evidence: Level IV, case series.

Disseminated Glioneuronal Tumor: A rare presentation in children

Gliomas, though most common pediatric central nervous system tumor, can manifest as disseminated glio-neuronal tumor, a rare variant in children. Clinical presentation depends on its location, type and age of child. We are presenting 8 years old male child with fever, projectile vomiting and severe headache which woke him up from deep sleep for 1 month. He had positive meningeal signs and raised intracranial tension with cerebrospinal fluid picture suggestive of partially treated meningitis. There was no improvement even on adequate duration of intravenous antibiotics and had appearance of new onset false localizing signs, MRI brain showed features of cryptococcal meningitis for which India ink staining was negative. As clinical picture was unlike of meningitis, repeat 3 tesla MRI brain was done. Expert neuro-radiologist’s opinion was in favor of disseminated glio-neuronal tumor which was confirmed on histopathological examination. Child underwent laminectomy in TATA memorial hospital and advised palliative care. Child succumbed at home within 6 months of illness.

Investigation of cortical thickness and volume during spontaneous attacks of migraine without aura: a 3-Tesla MRI study

Background Structural imaging has revealed changes in cortical thickness in migraine patients compared to healthy controls is reported, but presence of dynamic cortical and subcortical changes during migraine attack versus inter-ictal phase is unknown. The aim of the present study was to investigate possible changes in cortical thickness during spontaneous migraine attacks. We hypothesized that pain-related cortical area would be affected during the attack compared to an inter-ictal phase. Methods Twenty-five patients with migraine without aura underwent three-dimensional T1-weighted imaging on a 3-Tesla MRI scanner during spontaneous and untreated migraine attacks. Subsequently, 20 patients were scanned in the inter-ictal phase, while 5 patients did not show up for the inter-ictal scan. Four patients were excluded from the analysis because of bilateral migraine pain and another one patient was excluded due to technical error in the imaging. Longitudinal image processing was done using FreeSurfer. Repeated measures ANOVA was used for statistical analysis and to control for multiple comparison the level of significance was set at p = 0.025. Results In a total of 15 patients, we found reduced cortical thickness of the precentral (p = 0.023), pericalcarine (p = 0.024), and temporal pole (p = 0.017) cortices during the attack compared to the inter-ictal phase. Cortical volume was reduced in prefrontal (p = 0.018) and pericalcarine (p = 0.017) cortices. Hippocampus volume was increased during attack (p = 0.007). We found no correlations between the pain side or any other clinical parameters and the reduced cortical size. Conclusion Spontaneous migraine attacks are accompanied by transient reduced cortical thickness and volume in pain-related areas. The findings constitute a fingerprint of acute pain in migraine patients, which can be used as a possible biomarker to predict antimigraine treatment effect in future studies. Trial registration The study was registered at ClinicalTrials.gov (NCT02202486).

Habitual side-specific loading leads to structural, mechanical and compositional changes in the patellar tendon of young and senior life-long male athletes

Effects of life-long physical activity on tendon function have been investigated in cross-sectional studies, but these are at risk of "survivorship" bias. Here, we investigate if life-long side-specific loading is associated with greater cross-sectional area (CSA), mechanical properties, cell density (DNA content) and collagen cross-link composition of the male human patellar tendon (PT), in vivo. Nine seniors and six young male life-long elite badminton players and fencers were included. CSA of the PT obtained by 3-tesla MRI, and ultrasonography-based bilateral PT mechanics were assessed. Collagen fibril characteristics, enzymatic cross-links, non-enzymatic glycation (autofluorescence), collagen and DNA content were measured biochemically in PT biopsies. The elite athletes had a ≥15% side-to-side difference in maximal knee extensor strength, reflecting chronic unilateral sport-specific loading patterns. The PT CSA was greater on the lead extremity compared with the non-lead extremity (17 %, p=0.0001). Furthermore, greater tendon stiffness (18 %, p=0.0404) together with lower tendon stress (22 %, p=0.0005) and tendon strain (18 %, p=0.0433) were observed on the lead extremity. No effects were demonstrated from side-to-side for glycation, enzymatic cross-link, collagen, and DNA content (50%, p=0.1160). Moreover, tendon fibril density was 87±28 fibrils/μm2 on the lead extremity and 68±26 fibrils/μm2 on the non-lead extremity (28%, p=0.0544). Tendon fibril diameter was 86±14 nm on the lead extremity and 94±14 nm on the non-lead extremity (-9%, p=0.1076). These novel data suggest that life-long side-specific loading in males yields greater patellar tendon size and stiffness possibly with concomitant greater fibril density but without changes of collagen cross-link composition.

White Matter Hyperintensity Volume and Location: Associations With WM Microstructure, Brain Iron, and Cerebral Perfusion

Cerebral white matter hyperintensities (WMHs) represent macrostructural brain damage associated with various etiologies. However, the relative contributions of various etiologies to WMH volume, as assessed via different neuroimaging measures, is not well-understood. Here, we explored associations between three potential early markers of white matter hyperintensity volume. Specifically, the unique variance in total and regional WMH volumes accounted for by white matter microstructure, brain iron concentration and cerebral blood flow (CBF) was assessed. Regional volumes explored were periventricular and deep regions. Eighty healthy older adults (ages 60–86) were scanned at 3 Tesla MRI using fluid-attenuated inversion recovery, diffusion tensor imaging (DTI), multi-echo gradient-recalled echo and pseudo-continuous arterial spin labeling sequences. In a stepwise regression model, DTI-based radial diffusivity accounted for significant variance in total WMH volume (adjusted R2 change = 0.136). In contrast, iron concentration (adjusted R2 change = 0.043) and CBF (adjusted R2 change = 0.027) made more modest improvements to the variance accounted for in total WMH volume. However, there was an interaction between iron concentration and location on WMH volume such that iron concentration predicted deep (p = 0.034) but not periventricular (p = 0.414) WMH volume. Our results suggest that WM microstructure may be a better predictor of WMH volume than either brain iron or CBF but also draws attention to the possibility that some early WMH markers may be location-specific.