Impaired oxygen and cellular metabolism is a hallmark of ischaemic injury in acute stroke. Magnetic resonance spectroscopic imaging (MRSI) has long been recognized as a potentially powerful tool for non-invasive metabolic imaging. Nonetheless, long acquisition time, poor spatial resolution, and narrow coverage have limited its clinical application. Here we investigated the feasibility and potential clinical utility of rapid, high spatial resolution, near whole-brain 3D metabolic imaging based on a novel MRSI technology. In an 8-min scan, we simultaneously obtained 3D maps of N-acetylaspartate and lactate at a nominal spatial resolution of 2.0 × 3.0 × 3.0 mm3 with near whole-brain coverage from a cohort of 18 patients with acute ischaemic stroke. Serial structural and perfusion MRI was used to define detailed spatial maps of tissue-level outcomes against which high-resolution metabolic changes were evaluated. Within hypoperfused tissue, the lactate signal was higher in areas that ultimately infarcted compared with those that recovered (P < 0.0001). Both lactate (P < 0.0001) and N-acetylaspartate (P < 0.001) differed between infarcted and other regions. Within the areas of diffusion-weighted abnormality, lactate was lower where recovery was observed compared with elsewhere (P < 0.001). This feasibility study supports further investigation of fast high-resolution MRSI in acute stroke.

Bilateral sensorineural deafness and unilateral cochlear ossification have rarely been described in patients with chronic myeloid leukemia (CML). A 21-year-old man presented to a hospital with right-sided sudden hearing loss and tinnitus. He was diagnosed with CML. Five days later, sudden hearing loss appeared in the other ear. Abnormality of the right-sided inner ear structure was revealed by preoperative magnetic resonance imaging; honeycomb-like cochlear ossification was observed during cochlear implant surgery in the right ear. The patient’s auditory performance exhibited significant improvement after bilateral cochlear implantation in our hospital. Hematological disorders must be considered in patients with sensorineural hearing loss. Cochlear implantation is feasible in patients with CML who exhibit sensorineural deafness, but cochlear ossification should be carefully evaluated by means of preoperative imaging examinations.

Background Neurometabolite concentrations provide a direct index of infarction progression in stroke. However, their relationship with stroke onset time remains unclear. Purpose To assess the temporal dynamics of N‐acetylaspartate (NAA), creatine, choline, and lactate and estimate their value in predicting early (<6 hours) vs. late (6–24 hours) hyperacute stroke groups. Study Type Cross‐sectional cohort. Population A total of 73 ischemic stroke patients scanned at 1.8–302.5 hours after symptom onset, including 25 patients with follow‐up scans. Field Strength/Sequence A 3 T/magnetization‐prepared rapid acquisition gradient echo sequence for anatomical imaging, diffusion‐weighted imaging and fluid‐attenuated inversion recovery imaging for lesion delineation, and 3D MR spectroscopic imaging (MRSI) for neurometabolic mapping. Assessment Patients were divided into hyperacute (0–24 hours), acute (24 hours to 1 week), and subacute (1–2 weeks) groups, and into early (<6 hours) and late (6–24 hours) hyperacute groups. Bayesian logistic regression was used to compare classification performance between early and late hyperacute groups by using different combinations of neurometabolites as inputs. Statistical Tests Linear mixed effects modeling was applied for group‐wise comparisons between NAA, creatine, choline, and lactate. Pearson's correlation analysis was used for neurometabolites vs. time. P < 0.05 was considered statistically significant. Results Lesional NAA and creatine were significantly lower in subacute than in acute stroke. The main effects of time were shown on NAA (F = 14.321) and creatine (F = 12.261). NAA was significantly lower in late than early hyperacute patients, and was inversely related to time from symptom onset across both groups (r = −0.440). The decrease of NAA and increase of lactate were correlated with lesion volume (NAA: r = −0.472; lactate: r = 0.366) in hyperacute stroke. Discrimination was improved by combining NAA, creatine, and choline signals (area under the curve [AUC] = 0.90). Data Conclusion High‐resolution 3D MRSI effectively assessed the neurometabolite changes and discriminated early and late hyperacute stroke lesions. Evidence Level 1. Technical Efficacy Stage 2.

Spontaneous unilateral quadriceps tendon rupture is an uncommon injury that is generally associated with chronic kidney disease and metabolic disorders. The current case involved a 50-year-old man with a painful right knee that he was unable to extend as a result of minor trauma sustained in an accident. Physical examination combined with radiographic and ultrasonographic investigations led to a diagnosis of quadriceps tendon rupture of the right knee. The patient had a 7-year history of hemodialysis for treatment of chronic kidney disease, leading to secondary hyperparathyroidism. He underwent successful tendon repair surgery, and his right knee was immobilized with splints for 6 weeks postoperatively. He gradually resumed full weight bearing and then normal walking.

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