Diagnostic accuracy of CEMRA and CTA do not differ significantly in patients with subarachnoid haemorrhage


A study, led by Willem van Zwam, Maastricht University Medical Centre, Maastricht, The Netherlands, published ahead of print in the eJournal of the European Society of Minimally Invasive Neurological Therapy (EJMINT) investigated whether contrast enhanced magnetic resonance angiography (CEMRA) could be an alternative in diagnosing intracranial aneurysms in patients presenting with subarachnoid haemorrhage compared with computed tomographic angiography (CTA).

In a previous study CEMRA was compared with time-of-flight magnetic resonance angiography (TOF MRA) with digital subtraction angiography (DSA). All aneurysms were detected better by CEMRA than TOF MRA. However, according to van Zwam et al there was a “Lack of data about the comparative accuracy of CEMRA and CTA.” Therefore, the authors aimed to assess the accuracy of CEMRA in comparison to CTA for patients with subarchnoid haemorrhage (SAH) in detecting intracranial aneurysms.

The Patients, adults presenting with non-traumatic SAH diagnosed by CT or lumbar puncture 2004–2006 were included. In the study, 189 patients (of which 75 were included in the study) underwent CTA for detection of possible cerebral aneurysms and within 48 hours of CTA patients underwent CEMRA before endovascular or surgical treatment.

According to the authors, the quality of the images was rated good in 62.7% (47/75) of patient’s images by observer one and 72% (54/75) by observer two for CTA and 82.7% (62/75) by observer one and 86.7% (65/75) by observer two for CEMRA. The results show that in the study population 50.8% (33/65) of the aneurysms were smaller than 5mm and 18.5% (12/65) were smaller than 3mm. The observer’s sensitivities for detection were slightly better with CEMRA than CTA; however the difference was not significant.

According to the results CEMRA does not appear to be superior to CTA in the detection of intracranial aneurysms. “With the recent developments in CT techniques it is unlikely that CEMRA will be better in detecting intracranial aneurysms at this moment or in the near future, and therefore CTA is still the preferred diagnostic modality in patients with a subarachnoid haemorrhage,” van Zwam added.