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Purpose Quantitative susceptibility mapping (QSM) is influenced by iron as well as myelin, which makes interpretation of pathologic changes challenging. Concurrent acquisition of MR sequences that are sensitive to axonal/myelin integrity, such as diffusion tensor imaging (DTI), may provide context for interpreting quantitative susceptibility (QS) signal. The purpose of our study was to investigate alterations in normal-appearing white matter (NAWM) in multiple sclerosis (MS) using QSM in conjunction with DTI. Methods Twenty relapsing–remitting MS patients and 20 age-matched healthy controls (HC) were recruited for this prospective study. QS, radial diffusivity (RD), fractional anisotropy (FA), and R2* maps within the whole brain as well as individual tracts were generated for comparison between NAWM and HC white matter (HCWM). Results MS lesions demonstrated significant differences in QS, FA, RD, and R2* compared to HCWM (p < 0.03). These metrics did not show a significant difference between whole-brain NAWM and HCWM. Among NAWM tracts, the cingulate gyri demonstrated significantly decreased QS compared to HCWM (p = 0.004). The forceps major showed significant differences in FA and RD without corresponding changes in QS (p < 0.01). Conclusion We found discordant changes in QSM and DTI metrics within the cingulate gyri and forceps major. This may potentially reflect the influence of paramagnetic substrates such as iron, which could be decreased along these NAWM tracts. Our results point to the potential role of QSM as a unique biomarker, although additional validation studies are needed.

Foreign bodies contribute to more than half a million emergency department visits each year. 1 Grill-cleaning wire brush bristle is an infrequently identified foreign body with less than 25 published cases. 2 Grill-cleaning brushes are common consumer products. Their thin malleable bristles can break off easily and may be difficult to identify when stuck on food. 3 The sharp metallic bristles can embed into the tissues, making direct and radiographic visualization difficult. We present 2 recent cases and review prior cases of wire brush bristles in the head/neck region available on PubMed with a focus on the diagnostic approach.

There are several methods for long head of the biceps (LHB) tenodesis, yet the optimal option is still debatable. Here we introduce a technique for arthroscopic suprapectoral biceps tenodesis with an all-suture anchor, the transtendinous biceps tenodesis technique. The LHB tenodesis is performed by using the Y-Knot anchor (1.3-mm). A standard suprapectoral approach is used for the tenodesis. A 1.3-mm drill bit is used to drill through the midportion of the biceps tendon and underlying bone to make a pilot hole. Next, the Y-Knot anchor is passed through the tendon and anchored on the underlying bone. A wrapping suture technique is then used to wrap around, tension, and secure the LHB tendon with the aid of a shuttling polydioxanone suture. The construct is fixed by tying down both suture limbs in a nonsliding fashion. This Technical Note describes an alternative method for all-arthroscopic suprapectoral biceps tenodesis using an all-suture anchor with a small diameter to minimize trauma to the tendon.

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ObjectivesTenotomy and tenodesis of the long head of biceps tendon are effective pain-relieving treatments. However, there is no consensus on the functional outcome after these surgical procedures. We hypothesized that there would be no difference in ambulation parameters after recovery from the surgery between rats that underwent tenotomy versus tenodesis procedures.MethodsTwenty-four New Zealand rats were used and randomly divided into three groups. Each group received one of the following surgeries: tenotomy, tenodesis, and sham operation. A video-based walking track system was applied for gait analysis at day −1, 1, 3, 5, 7, 14 and 21 for each rat. Temporal and spatial parameters were obtained, and asymmetric index was calculated for each parameter.ResultsCompared to the tenotomy and sham-operated groups, the rats in the tenodesis group had shorter stance phase, longer swing time, longer step length, smaller paw length, smaller intermediary toe-spread length, smaller toe-spread length, and larger foot angle right after the tenodesis procedure. After day 14, all parameters were equivalent to those of the sham-operated group. At the end of the study, there were no functional changes found in tenotomy and tenodesis groups compared with the sham-operated group and preoperative status.ConclusionTransient functional alterations in temporal and spatial parameters are found after tenotomy and tenodesis in a rat model. The functional changes in the tenodesis group existed for a longer period than in tenotomy group; however, and all parameters showed no significant differences when compared with the sham group at the conclusion of the study.

A 30-year-old male presented with left facial pain and numbness. Initial MRI demonstrated an enhancing mass involving the left trigeminal nerve. Follow-up imaging showed interval growth with erosion of the sphenoid body. Surgical resection was performed and immunohistochemistry staining was consistent with an atypical teratoid/rhabdoid tumor. Awareness of this entity and its imaging features such as diffusion restriction, intratumoral hemorrhage, and bony destruction, can help guide confirmatory diagnostic testing and appropriate therapy.