1. Icahn School of Medicine Mount Sinai Hospital
eP-121
CT Perfusion to Predict Complete Recanalization in Patients with Acute Ischemic Stroke (AIS)
Mesha Martinez, MD; James Knitter, MS; Daniel Brown, MD; Reade De Leacy, MD; Johanna Fifi, MD; Kambiz Nael, MD
Icahn School of Medicine Mount Sinai Hospital

2. No Disclosures

3. PURPOSE
Identify CT perfusion parameters that can predict complete recanalization in patients with AIS who undergo mechanical thrombectomy

4. BACKGROUND Complete recanalization Perfusion Imaging
main goal of endovascular stroke therapy1,2
important determinant of clinical recovery1,2
Perfusion Imaging
Increasingly used in many centers world wide before endovascular intervention
Various parameters have been shown to predict infarct core3, outcomes and prognosis in AIS patients4, risk of hemorrhagic conversion5 and status of collateral circulation6

5. MATERIAL AND METHODS RETROSPECTIVE STUDY INCLUSION CRITERIA
Presented with AIS to the Mount Sinai healthcare system in
Baseline CT perfusion (CTP)
Conventional angiogram within 24 hours
EXCLUSION CRITERIA
Nondiagnostic quality of CTP
Infarctions in the distribution of the anterior and posterior cerebral arteries

6. MATERIALS AND METHODS CON’T
CT PERFUSION
CT perfusion data was processed with Bayesian* probabilistic method
*Advantages of Bayesian:
Minimizes effects of oscillation and overfitting (SVD)
Less sensitive to noise/low SNR
Higher resistance against dispersion (tracer delay)
Arterial transit delay, cerebral blood volume and cerebral blood flow maps were generated and processed with the following thresholds
THRESHOLDS
Delayed Perfusion (2 sec)
Hypoperfusion (2 sec – 6 sec)
Critical Hypoperfusion (>6 sec)

7. MATERIALS AND METHOD CON’T
Volume of delayed perfusion (Vol-ATD2sec)
Volume of hypoperfusion (Vol-ATD 2sec-6sec)
Volume of critical hypoperfusion (Vol-ATD6sec)
CBV and CBF corresponding to each of the above volumes
ATD > 2s
CBV
ATD > 6s
2s < ATD <6s

8. MATERIALS AND METHODS CON’T
CONVENTIONAL ANGIOGRAM
Two Neurointerventionalists (one neurology trained and the other radiology trained) reviewed the conventional angiograms of each patient and determined the grade of recanalization assigning them a TICI score

9. MATERIALS AND METHODS CON’T
STATISTICAL ANALYSIS
Repeated measures ANOVA and receiver operating curve analyses were performed to determine CTP biomarkers optimal for predicating complete recanalization

10. RESULTS OUR SAMPLE POPULATION # Male 4 Female 7 % Administered IV TPA36
Baseline NIHSS score >16 56
Complete Recanalization 64
TOTAL PATIENTS: 11
MEAN AGE:
(RANGE) 72
(48-85) %
Male
Female
Administered IV TPA
Baseline NIHSS score >
Complete Recanalization
58%
TOTAL PATIENTS: 11
MEAN AGE:
(RANGE)

11. RESULTS CON’T SUMMATIVE TABLE Recanalized TICI Recanalized
Not Recanalized
Mean
(mL) SD
Mean (mL)
P- value
Delayed Perfusion volume
ATD > 2s
68.3
42.8
71.6
44.4
0.9
Hypoperfusion
2s < ATD <6s
9.7
6.5
53.4
26.5
0.011
Critical Hypoperfusion
ATD > 6s
3.3
12.8
22.3
17.7
0.06
CBF x Hypoperfusion volume
CBF x 2s < ATD <6s
47.2
23.2
7.2
1.2
0.012
CBF 1
0.3
0.6
0.4

12. CBF x Hypoperfusion ROC
RESULTS CON’T
CBF x Hypoperfusion ROC
Threshold > 26.4
Sensitivity
86%
Specificity
100%
TRUE POSTIVE RATE
(SENSITIVITY)
AUC: 0.96
FALSE POSITIVE RATE
(1-SPECIFICITY)

13. CONCLUSIONS
Hypoperfused tissue volume defined as ADT 6-2 sec and its corresponding cerebral blood flow
are pre-procedural CT parameters that can predict complete recanalization in patients with AIS after mechanical thrombectomy

14. REFERENCES
1) Wintermark, Max, et al. "Acute stroke imaging research roadmap II." Stroke 44.9 (2013):
2) Zaidat, Osama O., et al. "Thrombolytic therapy of acute ischemic stroke: correlation of angiographic recanalization with clinical outcome." American journal of neuroradiology 26.4 (2005):
3) Campbell, Bruce CV, et al. "Cerebral blood flow is the optimal CT perfusion parameter for assessing infarct core." Stroke 42.12 (2011):
4) van Seeters, Tom, et al. "Prediction of outcome in patients with suspected acute ischaemic stroke with CT perfusion and CT angiography: the Dutch acute stroke trial (DUST) study protocol." BMC neurology 14.1 (2014): 1.
5) Jain, A. R., et al. "Association of CT perfusion parameters with hemorrhagic transformation in acute ischemic stroke." American Journal of Neuroradiology 34.10 (2013):
6) Nael, Kambiz, et al. "MR Perfusion to Determine the Status of Collaterals in Patients With Acute Ischemic Stroke: Look Beyond Perfusion Time-maps." Stroke 47.Suppl 1 (2016): A61-A61.