Federico D'Orazio, Presenter: Nothing to Disclose

Alessandra Splendiani MD, Abstract Co-Author: Nothing to Disclose

Aldo Victor Giordano, Abstract Co-Author: Nothing to Disclose

Sergio Carducci, Abstract Co-Author: Nothing to Disclose

Massimo Gallucci MD, Abstract Co-Author: Nothing to Disclose

Carlo Masciocchi MD, Abstract Co-Author: Nothing to Disclose

To evaluate the diagnostic potentials of ECG­-gated CT angiography (CTA) in identifying a sub-population of unbroken aneurysms with higher rupture risk, and the rupture site when studying ruptured intracranial aneurysms.

In the period between January 2012 and December 2013, 70 ECG­-gated CTA were performed using a 320 row­ detector CT scanner,in as many patients with cerebral aneurysms both broken and not. Scan protocol was designed as follows: first scan without contrast media: FOV=160mm/120KV/300mA/Rot.Time=0,35s/Collimation=0,5mm; second scan, with contrast enhancement and superimposable on the first to obtain further bone subtraction, had duration of one heart beat between an R­-R interval and was acquired co-registering the patient's ECG. The subtracted volume was reconstructed with a step interval of 5%, obtaining 20 volumes per each contrast scan. An MPR and 3D rendering of the aneurysms could then be observed in motion during the whole R-­R interval. The sites where abnormal/not synchronized movement of the aneurysmal wall were found, were subsequently compared with its intra-operative observation during neurosurgical treatment, which was filmed.

Among the aneurysms studied, 55 belonged to the anterior circulation and 15 to the posterior one. We found abnormal or not synchronized movement in part of the aneurysmal wall in 15% of the unbroken intracranial aneurysms; similar findings were found in about 45% of the broken aneurysms studied in emergency before surgical treatment, and in that case it always matched with the cleavage site highlighted during surgery.

ECG­-gated CTA is a promising add to the study of intracranial aneurysms. It can help in identifying a subpopulation of intracranial aneurysms with higher risk of rupture or directly demonstrate the site of rupture before surgical treatment. This information can be useful when planning both their endovascular and surgical treatment.

When in an ECG-gated intracranial CTA a not-synchronous movement of part of the aneurysmal wall is observed, this may correspond (in the case of a ruptured aneurysm) to the rupture site, or may actually correspond (in an aneurysm with higher risk of rupture) to the region of higher weakening of its wall.

D'Orazio, F, Splendiani, A, Giordano, A, Carducci, S, Gallucci, M, Masciocchi, C, ECG­-Gated CT Angiography of Intracranial Aneurysms (Broken and Not) Using 320 Row ­Detector CT Scanner: Identification of Higher­ Risk Aneurysms and Rupture Site before Surgery..  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045648.html