Anti-Hu-Associated Autoimmune Limbic Encephalitis in a Patient with PD-1 Inhibitor-Responsive Myxoid Chondrosarcoma.

Autoimmune encephalitis is an uncommon complication of immune checkpoint inhibitor therapy. This article reports a case of fatal anti-Hu-associated autoimmune limbic encephalitis presenting within 8 weeks following anti-PD1 therapy in a patient with myxoid chondrosarcoma and pre-existing anti-Hu antibodies. Although tumor reduction occurred in response to PD-1 inhibitor therapy, the patient had a rapidly progressive decline in neurologic function despite initial stabilization with immunosuppression. Considering the increasing use of immune checkpoint inhibitors for the treatment of various malignancies, an increase in the occurrence of neurologic adverse events is likely, requiring prompt intervention and enhanced pharmacovigilance in malignancies associated with onconeuronal antibodies.

Contrast-enhanced 3-dimensional SPACE versus MP-RAGE for the detection of brain metastases: considerations with a 32-channel head coil.

PURPOSE: The aim of this study was to compare the detection of brain metastases at 3 T using a 32-channel head coil with 2 different 3-dimensional (3D) contrast-enhanced sequences, a T1-weighted fast spin-echo-based (SPACE; sampling perfection with application-optimized contrasts using different flip angle evolutions) sequence and a conventional magnetization-prepared rapid gradient-echo (MP-RAGE) sequence. MATERIALS AND METHODS: Seventeen patients with 161 brain metastases were examined prospectively using both SPACE and MP-RAGE sequences on a 3-T magnetic resonance system. Eight healthy volunteers were similarly examined for determination of signal-to-noise ratio (SNR) values. Parameters were adjusted to equalize acquisition times between the sequences (3 minutes and 30 seconds). The order in which sequences were performed was randomized. Two blinded board-certified neuroradiologists evaluated the number of detectable metastatic lesions with each sequence relative to a criterion standard reading conducted at the Gamma Knife facility by a neuroradiologist with access to all clinical and imaging data. RESULTS: In the volunteer assessment with SPACE and MP-RAGE, SNR (10.3 ± 0.8 vs 7.7 ± 0.7) and contrast-to-noise ratio (0.8 ± 0.2 vs 0.5 ± 0.1) were statistically significantly greater with the SPACE sequence (P < 0.05). Overall, lesion detection was markedly improved with the SPACE sequence (99.1% of lesions for reader 1 and 96.3% of lesions for reader 2) compared with the MP-RAGE sequence (73.6% of lesions for reader 1 and 68.5% of lesions for reader 2; P < 0.01). CONCLUSIONS: A 3D T1-weighted fast spin echo sequence (SPACE) improves detection of metastatic lesions relative to 3D T1-weighted gradient-echo-based scan (MP-RAGE) imaging when implemented with a 32-channel head coil at identical scan acquisition times (3 minutes and 30 seconds).

Percutaneous sacroplasty: long-axis injection technique.

OBJECTIVE: Sacroplasty, or the injection of percutaneous polymethyl methacrylate into a sacral insufficiency fracture, has been previously described using needle placement in the short axis of the sacrum. We describe a new technique of needle placement along the long axis of the sacrum. CONCLUSION: This approach is easier to perform and results in improved cement distribution along the length of the sacral ala.