PDF(Pubmed)
Abstract：
Diagnosing recent small subcortical infarcts (RSSIs) via early computed tomography (CT) remains challenging. This study aimed to assess CT attenuation values (Hounsfield Units (HU)) and net water uptake (NWU) in RSSI and explore a postprocessing algorithm\'s potential to enhance thalamic RSSI detection. We examined non-contrast CT (NCCT) data from patients with confirmed thalamic RSSI on diffusion-weighted magnetic resonance imaging (DW-MRI) between January 2010 and October 2017. Co-registered DW-MRI and NCCT images enabled HU and NWU quantification in the infarct area compared to unaffected contralateral tissue. Results were categorized based on symptom onset to NCCT timing. Postprocessing using window optimization and frequency-selective non-linear blending (FSNLB) was applied, with interpretations by three blinded Neuroradiologists. The study included 34 patients (median age 70 years [IQR 63-76], 14 women). RSSI exhibited significantly reduced mean CT attenuation compared to unaffected thalamus (29.6 HU (±3.1) vs. 33.3 HU (±2.6); p < 0.01). Mean NWU in the infarct area increased from 6.4% (±7.2) at 0-6 h to 16.6% (±8.7) at 24-36 h post-symptom onset. Postprocessed NCCT using these HU values improved sensitivity for RSSI detection from 32% in unprocessed CT to 41% in FSNLB-optimized CT, with specificities ranging from 86% to 95%. In conclusion, CT attenuation values and NWU are discernible in thalamic RSSI up to 36 h post-symptom onset. Postprocessing techniques, particularly window optimization and FSNLB, moderately enhance RSSI detection.
摘要：
通过早期计算机断层扫描（CT）诊断最近的小皮质下梗塞（RSSIs）仍然具有挑战性。本研究旨在评估RSSI中的CT衰减值（Hounsfield单位（HU））和净吸水（NWU），并探索后处理算法增强丘脑RSSI检测的潜力。我们检查了2010年1月至2017年10月在弥散加权磁共振成像（DW-MRI）上确认丘脑RSSI的患者的非对比CT（NCCT）数据。与未受影响的对侧组织相比，共同配准的DW-MRI和NCCT图像可对梗死区域进行HU和NWU定量。根据症状发作到NCCT时机对结果进行分类。使用窗口优化和频率选择性非线性混合（FSNLB）进行后处理，由三位盲目的神经放射学家解释。该研究包括34例患者（中位年龄70岁[IQR63-76]，14名妇女）。与未受影响的丘脑相比，RSSI显示出平均CT衰减显着降低（29.6HU（±3.1）与33.3HU(±2.6);p<0.01)。梗死区的平均NWU从症状发作后0-6小时的6.4％（±7.2）增加到24-36小时的16.6％（±8.7）。使用这些HU值的后处理NCCT将RSSI检测的灵敏度从未处理CT的32%提高到FSNLB优化CT的41%,特异性范围从86%到95%。总之,症状发作后36小时，丘脑RSSI中的CT衰减值和NWU是可辨别的。后处理技术，特别是窗口优化和FSNLB，适度增强RSSI检测。
