The dense basilar artery as a sign of basilar territory infarction

Three-month and long-term outcomes and their predictors in acute basilar artery occlusion treated with intra-arterial thrombolysis

BACKGROUND AND PURPOSE

Intra-arterial thrombolysis can be used for treatment of basilar artery occlusion. Predictors of outcome before initiation of treatment are of special interest.

METHODS

From 1992 to 2010, we treated 106 consecutive patients with basilar artery occlusion with intra-arterial thrombolysis. Baseline characteristics, treatment, clinical course, and 3-month and long-term outcomes (≥12 months) were assessed. Outcome parameters were vessel recanalization after treatment, complications, modified Rankin scale (mRS) score, and mortality after 3 months and in the long-term.

RESULTS

At 3 months, clinical outcome was good (mRS score, 0-2) in 33.0% of the patients and moderate (mRS score, 3) in 11.3%. Mortality was 40.6%. Partial or complete recanalization was achieved in 69.8% of the patients, and symptomatic intracranial hemorrhage occurred in 1 patient (0.9%). Between 3-month and long-term follow-up, 22 survivors (40.8%) showed clinical improvement of at least 1 point on the mRS score, 29 (53.7%) were functionally unchanged, and 3 (5.7%) showed functional worsening (P<0.0001). Multivariate analysis identified diabetes as a predictor of poor vessel recanalization (P=0.028). Low baseline National Institutes of Health Stroke Scale score was identified as a predictor of good or moderate clinical outcome (P<0.0001) and survival (P=0.001) at 3 months, and younger age was identified as an additional predictor of survival (P=0.012). For prediction of long-term clinical outcome, age was also an independent predictor (P=0.018).

CONCLUSIONS

In our series, intra-arterial thrombolysis as treatment of basilar artery occlusion was safe. National Institutes of Health Stroke Scale score at admission and age were identified as predictors of outcome, and these predictors should be considered for treatment allocation in future randomized trials.

The Hyperdense Cerebral Artery Sign on Head CT Scan

The hyperdense artery sign on noncontrast head CT is thought to be one of the earliest and most useful signs of intra-arterial clot and probable (clinical) stroke. It should be evaluated in the context of the clinical scenario. Rigorous criteria should be applied in order to reduce potential false positives. The hyperdense middle cerebral artery sign is the most studied version and correlates with patient outcome. Our data suggest that the density on noncontrast head CT is not likely to universally represent in situ clot.

Clinical and radiological predictors of recanalisation and outcome of 40 patients with acute basilar artery occlusion treated with intra-arterial thrombolysis

OBJECTIVE

To define predictors of recanalisation and clinical outcome of patients with acute basilar artery occlusions treated with local intra-arterial thrombolysis (IAT).

METHODS

Vascular risk factors, severity of the neurological deficit graded by the National Institutes of Health stroke scale (NIHSS), and radiological findings were recorded at presentation. Outcome was measured using the modified Rankin scale (mRS) three months later and categorised as favourable (mRS 0-2), poor (mRS 3-5), or death (mRS 6).

RESULTS

40 patients were studied. Median NIHSS on admission was 18. Mean time from symptom onset to treatment was 5.5 hours (range 2.3 to 11). Outcome was favourable in 14 patients (35%) and poor in nine (23%); 17 (42%) died. There were two symptomatic cerebral haemorrhages (5%). Recanalisation of the basilar artery was achieved in 32 patients (80%); it was complete (TIMI grade 3) in 20% and partial (TIMI grade 2) in 60%. In multivariate logistic regression analysis, low NIHSS score on admission (p = 0.002) and vessel recanalisation (p = 0.005) were independent predictors of favourable outcome. Recanalisation occurred more often with treatment within six hours of symptom onset (p = 0.003) and when admission computed tomography showed a hyperdense basilar artery sign (p = 0.007). In a univariate model, quadriplegia (p = 0.002) and coma (p = 0.004) were associated with a poor outcome or death.

CONCLUSIONS

Low baseline NIHSS on admission and recanalisation of basilar artery occlusions predict a favourable outcome after intra-arterial thrombolysis. Early initiation of IAT and the presence of a hyperdense basilar artery sign on CT were associated with a higher likelihood of recanalisation.

Intra-arterial thrombolysis for vertebrobasilar circulation ischemia

Acute basilar artery occlusion is usually associated with a poor prognosis despite therapy with antiplatelet and anticoagulant agents. The natural history of this disorder should be fully understood before clinicians make decisions on therapy. Recent advances in angiography technique and the use of newer mobile microcatheters have made intra-arterial thrombolysis therapy feasible. There have been several small, uncontrolled series of intra-arterial thrombolysis in basilar artery occlusion with promising results.

Basilar artery occlusion and the dense artery sign in the newborn

A child with basilar artery occlusion in the neonatal period is reported. The occlusion was documented by unenhanced computed tomography performed in the neonatal period demonstrating a "dense" artery at the tip of the basilar artery. The pattern of cerebral damage on MRI scan at 10 years of age confirmed the site of the vascular occlusion. The evidence suggests that embolization was the operating pathogenic mechanism of cerebral vascular occlusion. Neonatal arterial thrombosis involving the carotid circulation has been well documented and may be due to many pathological factors including direct trauma to the carotid artery and embolization from remote sites. Thrombosis of the vertebral artery in the neonate is only rarely reported and only in association with significant cervical trauma. A second child with a similar pattern of cerebral injury demonstrated on neuroimaging is described suggesting that this event may be more common than recognized. The clinical features of basilar artery occlusion as seen in the adult are not apparent in the neonate. Recognition of the neuroimaging characteristics seen in this condition may help to provide the clinician with a reasonable pathogenetic explanation for unexplained cerebral injury.

Dense middle cerebral artery computed tomography sign: confirmation by magnetic resonance (MR) imaging and MR angiography

In acute ischaemic stroke, the dense middle cerebral artery sign on computed tomography indicates occlusion of the middle cerebral artery. A case is described in which the sign was confirmed by magnetic resonance (MR) imaging and MR angiography.