The Usefulness of 3D-CT Angiography as a Screening Tool for Vascular Abnormalities in Spontaneous ICH Patients

Computed tomography angiography or magnetic resonance angiography for detection of intracranial vascular malformations in patients with intracerebral haemorrhage

BACKGROUND

Intracranial vascular malformations (brain or pial/dural arteriovenous malformations/fistulae, and aneurysms) are the leading cause of intracerebral haemorrhage (ICH) in young adults. Early identification of the intracranial vascular malformation may improve outcome if treatment can prevent ICH recurrence. Catheter intra-arterial digital subtraction angiography (IADSA) is considered the reference standard for the detection an intracranial vascular malformation as the cause of ICH. Computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are less invasive than IADSA and may be as accurate for identifying some causes of ICH.

OBJECTIVES

To evaluate the diagnostic test accuracy of CTA and MRA versus IADSA for the detection of intracranial vascular malformations as a cause of ICH.

SEARCH METHODS

We searched MEDLINE (1948 to August 2013), EMBASE (1980 to August 2013), MEDION (August 2013), the Database of Abstracts of Reviews of Effects (DARE; August 2013), the Health Technology Assessment Database (HTA; August 2013), ClinicalTrials.gov (August 2013), and WHO ICTRP (International Clinical Trials Register Portfolio; August 2013). We also performed a cited reference search for forward tracking of relevant articles on Google Scholar (http://scholar.google.com/), screened bibliographies, and contacted authors to identify additional studies.

SELECTION CRITERIA

We selected studies reporting data that could be used to construct contingency tables that compared CTA or MRA, or both, with IADSA in the same patients for the detection of intracranial vascular malformations following ICH.

DATA COLLECTION AND ANALYSIS

Two authors (CBJ and RA-SS) independently extracted data on study characteristics and measures of test accuracy. Two authors (CBJ and PMW) independently extracted data on test characteristics. We obtained data restricted to the subgroup undergoing IADSA in studies using multiple reference standards. We combined data using the bivariate model. We generated forest plots of the sensitivity and specificity of CTA and MRA and created a summary receiver operating characteristic plot.

MAIN RESULTS

Eleven studies (n = 927 participants) met our inclusion criteria. Eight studies compared CTA with IADSA (n = 526) and three studies compared MRA with IADSA (n = 401). Methodological quality varied considerably among studies, with partial verification bias in 7/11 (64%) and retrospective designs in 5/10 (50%). In studies of CTA, the pooled estimate of sensitivity was 0.95 (95% confidence interval (CI) 0.90 to 0.97) and specificity was 0.99 (95% CI 0.95 to 1.00). The results remained robust in a sensitivity analysis in which only studies evaluating adult patients (≥ 16 years of age) were included. In studies of MRA, the pooled estimate of sensitivity was 0.98 (95% CI 0.80 to 1.00) and specificity was 0.99 (95% CI 0.97 to 1.00). An indirect comparison of CTA and MRA using a bivariate model incorporating test type as one of the parameters failed to reveal a statistically significant difference in sensitivity or specificity between the two imaging modalities (P value = 0.6).

AUTHORS' CONCLUSIONS

CTA and MRA appear to have good sensitivity and specificity following ICH for the detection of intracranial vascular malformations, although several of the included studies had methodological shortcomings (retrospective designs and partial verification bias in particular) that may have increased apparent test accuracy.

Vascular imaging adds value in investigation of basal ganglia hemorrhage

The risk of basal ganglia hemorrhage (BGH) increases in patients of older age and with hypertension. Current guidelines do not recommend routine vascular imaging. However, a proportion of patients with BGH have underlying vascular abnormalities, and these patients may require a different treatment approach. We aimed to assess the proportion of underlying vascular abnormalities in patients with BGH. In this retrospective study, we included all patients who presented with BGH between January 2007 and December 2009 at a single institution. The following data were collected: patient demographics, vascular risk factors, medications, volume of hematoma, CT scans, CT angiogram, magnetic resonance angiography and digital subtraction angiography. We determined the proportion of underlying vascular abnormalities and correlated these findings with risk factors for BGH. A total of 113 consecutive patients with BGH were identified, and vascular imaging was performed in 61. The median age was 62 years and 48 (78.7%) of these patients were male. Forty-two (68.9%) of 61 patients had hypertension. Positive vascular imaging findings were identified in eight of 61 patients (13.1%): three intracranial aneurysms, three cavernous malformations, one Moyamoya disease and one arteriovenous malformation. There were no significant associations between demographic features, vascular risk factors and the hematoma volume between patients with positive and negative vascular imaging. Specifically, an underlying vascular abnormality was not associated with age (≥ 60 years, 6/36 patients had an underlying vascular abnormality, compared with 2/25 patients< 60 years; p=not significant [n.s.]). There was no relationship with hypertension (5/42 hypertensive patients and 3/19 normotensive patients (n.s.) had an underlying vascular abnormality). We concluded that there is a significant proportion of relevant underlying vascular abnormalities in patients with BGH. This likelihood is not predicted by risk factors such as hypertension and age. These findings indicate the importance of vascular imaging in patients with BGH who are not neurologically devastated.