High sensitivity and specificity of 4D-CTA in the detection of cranial arteriovenous shunts

Abstract

PurposeIn a prospective cohort study, we evaluated the diagnostic accuracy of time-resolved CT angiography (4D-CTA) compared to digital subtraction angiography (DSA) for detecting cranial arteriovenous shunts.Material and methodsPatients were enrolled if a DSA had been ordered querying either a dural arteriovenous fistula (dAVF) or a cerebral arteriovenous malformation (bAVM). After enrolment, both a DSA and a 4D-CTA were performed. Both studies were evaluated using a standardized form. If a dAVF or bAVM was found, its classification, angioarchitectural details, and treatment options were recorded.ResultsNinety-eight patients were enrolled and 76 full datasets were acquired. DSA demonstrated a shunting lesion in 28 out of 76 cases (prevalence 37%). 4D-CTA demonstrated all but two of these lesions (sensitivity of 93%) and produced one false positive (specificity of 98%). These numbers yielded a positive predictive value (PPV) of 96% and a negative predictive value (NPV) of 96%. Significant doubt regarding the 4D-CTA diagnosis was reported in 6.6% of all cases and both false-negative 4D-CTA results were characterized by such doubt.Conclusions4D-CTA has very high sensitivity and specificity for the detection of intracranial arteriovenous shunts. Based on these results, 4D-CTA may replace DSA imaging as a first modality in the diagnostic workup in a large number of patients suspected of a cranial dAVF or bAVM, especially if there is no doubt regarding the 4D-CTA diagnosis.Key Points • 4D-CTA was shown to have a high diagnostic accuracy and is an appropriate, less invasive replacement for DSA as a diagnostic tool for cranial arteriovenous shunts in the majority of suspected cases. • Doubt regarding the 4D-CTA result should prompt additional DSA imaging, as it is associated with false negatives. • False-positive 4D-CTA results are rare, but do exist.

Evaluation of cerebral arteriovenous shunts: a comparison of parallel imaging time-of-flight magnetic resonance angiography (TOF-MRA) and compressed sensing TOF-MRA to digital subtraction angiography

“…However, this invasive technique carries a risk of neurological complications and adverse reactions associated with the contrast agent as well as the exposure to ionizing radiation during the procedure. Various non-or less-invasive imaging techniques have thus been applied to the evaluation of AVS [12][13][14][15][16][17][18][19][20][21][22]. Time-of-flight (TOF)-MRA has been the most widely used of these in clinical practice.…”

Current perspectives and trends in the treatment of brain arteriovenous malformations: a review and bibliometric analysis

“…Multiple studies have demonstrated that 4D-CTA possesses comparable or even superior capabilities to DSA in assessing the main feeding arteries, draining veins, and tumor nest size, with a higher detection rate for microcerebellar AVMs (diameter < 1 cm) compared to DSA ( 53 , 54 ). Furthermore, it exhibits enhanced diagnostic accuracy in detecting cranial arteriovenous shunts ( 55 ). However, given the current technology’s imperfections and the limited scope of related research to small series and case reports, 4D-CTA is currently considered an adjunctive tool to conventional non-invasive diagnostic techniques.…”

Is four-dimensional CT angiography as effective as digital subtraction angiography in the detection of the underlying causes of intracerebral haemorrhage: a systematic review

“…More recent studies have demonstrated an improvement in the diagnostic accuracy of CTA (3D-CTA and 4D-CTA) techniques for detecting underlying vascular abnormalities [5,9,15,19]. The improvement in 4D-CTA combines the traditional 3D-CTA with the 4th dimension of time to create a stereoscopic image continuously displaying blood vessels within the short interval of time taken for one investigation.…”

“…4D- CTA provides a large data set of images and thorough review of all images may help to reduce false-negative cases. For future studies, it would be prudent to assess inter-rater reliability to avoid the introduction of any potential errors that may be producing the observed variability [19]. The level of training for reading 4D-CTA scans should also be standardised across centres to reduce any potential discrepancies, particularly in nonspecialist district general hospitals.…”