（閱讀筆記）Rapid與兩大廠商CTP軟體預測比較

• Material and Methods
• • Study Design and Patient Cohort
  • CTP image Acquisiton
  • CTP Image Postprocessing and Analysis
• 其他

by HPC_ZY

期刊論文《Comparison of Perfusion CT Software to Predict the Final Infarct Volume After Thrombectomy》閱讀筆記。

Material and Methods

Study Design and Patient Cohort

data were analyzed from patients who were admitted to our clinic between March 2009 and December 2013 and who met the following inclusion criteria:

(1) acute ischemic stroke,

(2) initial noncontrast-enhanced computed tomography (NCCT), CT angiography to confrm occlusion of the internal carotid artery terminus or the middle cerebral artery and CTP

(3) MT performed

(4) follow-up NCCT or magnetic resonance imaging (MRI) between days 1 and 8.

（1） 急性缺血性中風；

（2） 初始非接觸增強計算機斷層掃描（NCCT），頸内動脈終末或大腦中動脈閉塞的CT血管造影及CTP檢查；

（3） 執行的MT；

（4） 随訪第1天至第8天的NCCT或磁共振成像（MRI）。

CTP image Acquisiton

All CT scans were performed using a 64-slice CT scanner equipped with a 40-mm wide detector (Brilliance 64, Philips Medical Systems, Best, The Netherlands). The imaging parameters for CTP were 80 kVp, 150 mAs, and 32×1.25 mm detector collimation and a scan duration of 60 s. After cerebral NCCT, CTP was conducted with the toggling table technique, allowing an extended coverage of the brain of 80 mm. A scan delay of 3 s was applied after injecting 60 mL (flow rate 5 mL/s) of iodinated contrast agent (350 mg I/mL Imeron 350, Bracco Imaging, Ravensburg, Germany).

CTP的成像參數為80kvp，150mas，32×1.25mm探測器準直，掃描時間為60s。注射60毫升（流速5毫升/秒）碘造影劑（350毫克/毫升）後，掃描延遲3秒。

CTP Image Postprocessing and Analysis

1. Brain CT Perfusion Package (Philips）

   The CTP parameters relative MTT and CBV distinguish the hypoperfusion and the ischemic core. Hypoperfusion is defned as a relative MTT >145% compared with the contralateral hemisphere. Ischemic core is also defned as a relative MTT >145% but has a CBV of <2.0 mL/100 g.[6,25]

   CTP參數相對MTT和CBV可區分低灌注和缺血核心。與對側半球相比，低灌注被定義為相對MTT>145%。缺血核心被定義為相對MTT>145%且CBV<2.0ml/100g.
2. Syngo Volume Perfusion CT Neuro (Siemens)

   CTP is performed using threshold values for relative CBF and relative CBV given by the vendor to distinguish between ischemic core (CBV <1.2 mL/100 mL) and hypoperfusion (CBF <35.1 mL/100 mL per minute).[19,27,28]

   使用相對CBF和相對CBV門檻值進行CTP參數計算，以區分缺血核心（CBV<1.2 mL/100 mL）和低灌注（CBF<35.1 mL/100 mL/min）。
3. RAPID (iSchemaView)

   Ischemic core is diagnosed if the relative CBF is <30% of that in normal tissue.8 Hypoperfusion is distinguished from minimally hypoperfused tissue if the T max delay is >6 s

   rCBF小于正常組織的30%，則診斷為缺血核心。果Tmax延遲大于6 s，則為缺血區。

值得注意的是，不同廠商判定缺血區和梗死區的标準是不一樣的。難怪之前在Philips，Siemens的灌注圖裡都沒看到Tmax。

其他

[1] Austein F, Riedel C, Kerby T, et al. Comparison of perfusion CT software to predict the final infarct volume after thrombectomy[J]. Stroke, 2016, 47(9): 2311-2317.

[28] Abels B, Klotz E, Tomandl B F, et al. Perfusion CT in acute ischemic stroke: a qualitative and quantitative comparison of deconvolution and maximum slope approach[J]. American Journal of Neuroradiology, 2010, 31(9): 1690-1698.