Vertebrobasilar thrombosis: diagnosis, management, and the use of intra-arterial thrombolytics

DWI Reversibility after Intra-Arterial Thrombolysis. A Case Report and Literature Review

We report our case and review the literature on reversal DWI lesions, ADC thresholds and correlation between DWI lesion and outcome measured with clinical scales. A 30-years old woman was admitted to our hospital 18 hours after stroke onset. Considering the absence of alterations on CT and the worsening of symptomatology, the patient underwent MRI, which showed a slightly hyperintense signal in FLAIR images in the left portion of the pons and midbrain and a more evident bilateral DWI hyperintensity of the pons. The patient was treated with mechanical and pharmacological intra-arterial thrombolysis. The patient showed a rapid improvement of symptoms. Two weeks after the treatment her clinical conditions were characterized by a residual right hemiparesis and complete recovery of right motility, respiratory and swallowing difficulties. MR examination demonstrated a slight signal alteration of the pons left hemiportion and a disappearance of the mesencephalic signal alteration and of the right portion of the pons. DWI lesions represent irreversibly damaged tissue but new evidence suggests that DWI lesions may be reversible, especially with reperfusion, by now well demonstrated in animal models. Therefore acute DWI lesions probably contain not only irreversibly injured tissue but also parts of the penumbra. The debate on the capability of ADC maps to discriminate irreversibly from reversibly damaged tissue is a matter of controversy. ADC values in human stoke are not an independent indicator of tissue viability. The use of thresholds may improve reproducibility but not validity.

Neurological complications and aspects of basilar artery occlusive disease

A recent case of basilar artery occlusion (BAO) in a 62-year-old woman is presented, along with a review of the literature on the clinical aspects of the disorder and treatment options. Therapeutic modalities such as intravenous and intra-arterial thrombolysis may significantly improve outcomes for patients with this disease.

Intra-arterial thrombolysis in basilar artery occlusion and recent haemorrhagic stroke due to arteriovenous malformation

We report the case of a young patient suffering from a severe ischaemic stroke due to basilar artery occlusion occurring during selective digital subtraction angiography. This examination was performed in order to assess an arteriovenous malformation in posterior cerebral artery territory responsible for haemorrhagic stroke occurring 17 days before. Intra-arterial thrombolysis with urokinase was performed and basilar artery recanalization was obtained 8 h after stroke onset. Despite the severe neurological impairment, the prolonged symptoms of ischaemia and the high bleeding risk due to the recent cerebral haemorrhage in the same vascular territory involved in thrombolysis, the treatment determined a very favourable clinical outcome.

The acute cerebrovascular event: surgical and other interventional therapies

Over the next decade, more early and aggressive treatments will become available for acute stroke. As EPs have been forced to push their skills and knowledge significantly further with the advent of time-sensitive interventions for myocardial ischemia, a similar sophistication will undoubtedly emerge in the management of acute stroke. Certain components of the neurological examination will likely assume a new significance and, as with the renewed focus on the nature of ST segment change on the ECG in ACS, there will be new attention to early imaging findings in stroke. Although it is unclear whether the balance of future advances in treatment will come from the world of neurosurgery, neurology, or interventional radiology, the EP is relatively assured to play a central role in their implementation.

Early false-negative diffusion-weighted imaging in brainstem infarction

It has been well established that acute ischemic lesions can be identified with diffusion-weighted imaging before they are detected on computed axial tomography or conventional magnetic resonance imaging sequences. Previous studies examining the sensitivity and specificity of diffusion-weighted imaging for acute stroke have dealt primarily with cortical stroke. Only limited information is available on the accuracy and temporal evolution of findings on diffusion-weighted imaging in patients with brainstem infarction. We present a case of lateral medullary infarction with false-negative diffusion-weighted imaging 16 hours after symptom onset and a brief review of the literature on the utility of diffusion-weighted imaging in early detection of brainstem stroke. Cases with false-negative initial imaging are increasingly more commonly reported in the literature, with initial images being obtained from 0.5 to over 24 hours after symptom onset. This delay in radiographic confirmation of brainstem stroke emphasizes the continuing need for accurate clinical diagnoses, especially in the early hours after symptom onset, when thrombolysis remains a treatment option. Delays in diagnosis and initiation of treatment of brainstem stroke may increase the associated morbidity and mortality.

Basilar artery thrombosis

Basilar artery thrombosis is an infrequent but important neurological emergency requiring early diagnosis and treatment. Of particular relevance to emergency medicine is the recognition and consideration of the unusual signs that may be present in an often previously well patient. It is therefore crucial to expedite investigations, confirm the diagnosis and commence life-saving treatment through the early involvement of a number of disciplines including neurology, radiology and intensive care. This paper confirms the use of magnetic resonance imaging and angiography as the preferred investigative mode and microcatheter directed intra-arterial thrombolysis as the treatment strategy of choice.

Factors affecting survival rates for acute vertebrobasilar artery occlusions treated with intra-arterial thrombolytic therapy: a meta-analytical approach

OBJECTIVE

To determine whether recanalization, coma at presentation, or clot location in the basilar artery influences the relative mortality risk after intra-arterial thrombolytic therapy for acute vertebrobasilar artery occlusions.

METHODS

Studies were identified using the MEDLINE database for January 1987 to November 1997. Series were included if they involved 10 or more patients with basilar or vertebrobasilar artery occlusions, used urokinase and/or recombinant tissue plasminogen activator, and were written in English. A fixed-effect meta-analysis approach was used to estimate the risk of death with the aforementioned risk factors. Each study was weighted according to sample size. Relative risks were calculated with 95% confidence intervals.

RESULTS

As calculated from peer-reviewed published data, the relative mortality risk for patients for whom recanalization was attempted but not achieved was 2.34 (95% confidence interval, 1.48-3.71; n = 126). Coma at presentation was associated with a relative mortality risk of 1.95 (95% confidence interval, 1.26-2.99; n = 145). Clot locations in the distal one-third of the basilar artery were shown to favor survival, compared with clots located in the proximal and/or middle portions of the basilar artery (relative risk, 0.52; 95% confidence interval, 0.31-0.86; n = 126).

CONCLUSION

The combined data suggest that coma at presentation has an independent and adverse effect on survival rates. Complete recanalization, distal clot location, and responsiveness at the time of presentation are statistically significant factors for increased patient survival rates.