Ukmar Maja, Degrassi Ferruccio, Pozzi Mucelli Roberta Antea, Neri Francesca, Mucelli Fabio Pozzi, Cova Maria Assunta
UCO di Radiologia Dipartimento di Scienze Mediche Chirurgiche e Tecnologiche, Università degli Studi di Trieste Ospedale di Cattinare (ASUITS), Trieste, Italy.
Br J Radiol. 2017 Apr;90(1072):20150472. doi: 10.1259/bjr.20150472.
To evaluate the accuracy of perfusion CT (pCT) in the definition of the infarcted core and the penumbra, comparing the data obtained from the evaluation of parametric maps [cerebral blood volume (CBV), cerebral blood flow (CBF) and mean transit time (MTT)] with software-generated colour maps.
A retrospective analysis was performed to identify patients with suspected acute ischaemic strokes and who had undergone unenhanced CT and pCT carried out within 4.5 h from the onset of the symptoms. A qualitative evaluation of the CBV, CBF and MTT maps was performed, followed by an analysis of the colour maps automatically generated by the software.
26 patients were identified, but a direct CT follow-up was performed only on 19 patients after 24-48 h. In the qualitative analysis, 14 patients showed perfusion abnormalities. Specifically, 29 perfusion deficit areas were detected, of which 15 areas suggested the penumbra and the remaining 14 areas suggested the infarct. As for automatically software-generated maps, 12 patients showed perfusion abnormalities. 25 perfusion deficit areas were identified, 15 areas of which suggested the penumbra and the other 10 areas the infarct. The McNemar's test showed no statistically significant difference between the two methods of evaluation in highlighting infarcted areas proved later at CT follow-up.
We demonstrated how pCT provides good diagnostic accuracy in the identification of acute ischaemic lesions. The limits of identification of the lesions mainly lie at the pons level and in the basal ganglia area. Qualitative analysis has proven to be more efficient in identification of perfusion lesions in comparison with software-generated maps. However, software-generated maps have proven to be very useful in the emergency setting. Advances in knowledge: The use of CT perfusion is requested in increasingly more patients in order to optimize the treatment, thanks also to the technological evolution of CT, which now allows a whole-brain study. The need for performing CT perfusion study also in the emergency setting could represent a problem for physicians who are not used to interpreting the parametric maps (CBV, MTT etc.). The software-generated maps could be of value in these settings, helping the less expert physician in the differentiation between different areas.
通过比较从参数图[脑血容量（CBV）、脑血流量（CBF）和平均通过时间（MTT）]评估中获得的数据与软件生成的彩色图，评估灌注CT（pCT）在梗死核心和半暗带定义中的准确性。
进行回顾性分析，以确定疑似急性缺血性卒中且在症状发作后4.5小时内接受了平扫CT和pCT检查的患者。对CBV、CBF和MTT图进行定性评估，随后分析软件自动生成的彩色图。
共确定了26例患者，但仅对19例患者在24 - 48小时后进行了直接CT随访。在定性分析中，14例患者显示灌注异常。具体而言，检测到29个灌注缺损区域，其中15个区域提示为半暗带，其余14个区域提示为梗死灶。对于软件自动生成的图，12例患者显示灌注异常。确定了25个灌注缺损区域，其中15个区域提示为半暗带，另外10个区域提示为梗死灶。McNemar检验显示，在突出CT随访后期证实的梗死区域方面，两种评估方法之间无统计学显著差异。
我们证明了pCT在识别急性缺血性病变方面具有良好的诊断准确性。病变识别的局限性主要在于脑桥水平和基底节区。与软件生成的图相比，定性分析在识别灌注病变方面已被证明更有效。然而，软件生成的图在急诊情况下已被证明非常有用。知识进展：由于CT技术的发展，现在可以进行全脑研究，越来越多的患者需要使用CT灌注来优化治疗。对于不习惯解读参数图（CBV、MTT等）的医生来说，在急诊情况下进行CT灌注研究可能是一个问题。软件生成的图在这些情况下可能有价值，有助于经验较少的医生区分不同区域。
