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Published on: September 25, 2016
Impact of flat-panel detector CT distal occlusion tracker (DOT) sign on early neurological deterioration after
Valentina Tudisco1,2, Michele Romoli3, Francesca Giannini2
1Stroke Unit, Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy.
Insights
The distal occlusion tracker (DOT) sign on CT scans after mechanical thrombectomy can predict early neurological deterioration in stroke patients. This imaging marker helps identify patients at higher risk for adverse outcomes.
Area of Science:
- Neurology
- Radiology
- Interventional Neurology
Background:
- Early neurological deterioration (END) is a significant complication following mechanical thrombectomy (MT) for acute ischemic stroke, even after successful recanalization.
- Identifying predictors of END is crucial for improving patient outcomes and treatment strategies.
Purpose of the Study:
- To prospectively assess the distal occlusion tracker (DOT) sign on flat-panel detector CT (FPDCT) immediately after MT.
- To determine if the DOT sign can predict early neurological deterioration (END) and identify distal embolization or incomplete microvascular reperfusion.
Main Methods:
- Prospective multicentre observational study of anterior circulation stroke patients treated with MT.
- Post-procedural FPDCT used to assess the DOT sign.
- Primary outcome: END. Secondary outcomes: 3-month functional outcome, 24-hour ASPECTS, and hemorrhagic complications.
- Logistic regression used to evaluate associations between the DOT sign and clinical-radiological variables.
Main Results:
- The DOT sign was present in 31% of cases and associated with higher rates of END (25% vs 12.8%, p=0.003).
- DOT sign presence correlated with lower recanalization success (79.3% vs 91.1%, p<0.001) and cortical hyperattenuation.
- Independent predictors of END included the DOT sign (aOR=2.07, p=0.040), cardioembolic aetiology, baseline NIHSS, FPDCT ASPECTS, and unsuccessful reperfusion.
Conclusions:
- The DOT sign is a practical post-thrombectomy imaging marker for predicting END.
- Integrating DOT sign assessment aids in stratifying tissue-at-risk and END risk.
- This marker can inform patient selection for adjunctive intra-arterial medications.
Background:
A relevant proportion of patients experience early neurological deterioration (END) despite technically successful recanalisation for acute ischaemic stroke. We prospectively assessed the distal occlusion tracker (DOT) sign, detectable on flat-panel detector CT (FPDCT) immediately after mechanical thrombectomy (MT), to identify distal embolisation or incomplete microvascular reperfusion associated with END.
Methods:
Our prospective multicentre observational study included consecutive patients with anterior circulation stroke treated with MT between January 2022 and December 2023 at two large comprehensive stroke centres. Post-procedural FPDCT was used to assess the presence of the DOT sign. The primary outcome was END. Secondary outcomes included 3 month functional outcome, 24 hour Alberta Stroke Program Early CT Score (ASPECTS) and haemorrhagic complications. Associations between the DOT sign and clinical-radiological variables, including Thrombolysis in Cerebral Infarction recanalization score (TICI), were evaluated through univariate and multivariate logistic regression.
Results:
The DOT sign was present in 31% of cases and was associated with higher rates of END (25% vs 12.8%, p=0.003), lower recanalisation success (79.3% vs 91.1%, p<0.001) and greater prevalence of cortical hyperattenuation. On multivariate analysis, independent predictors of END included the DOT sign (aOR=2.07, p=0.040), cardioembolic aetiology, baseline National Institutes of Health Stroke Scale, FPDCT ASPECTS and unsuccessful reperfusion. The DOT sign led to reclassification of half of TICI 3 cases to lower grades. No significant difference in symptomatic intracranial haemorrhage was observed between groups.
Conclusions:
The DOT sign is a practical post-thrombectomy imaging marker helping in the prediction of END. Integrating the DOT sign assessment may help in the stratification of tissues at risk and risk of END, adding to the selection of patients for adjunctive intra-arterial medications.
