OBJECTIVE: MR vessel wall imaging (VWI) is increasingly performed in clinical settings to support treatment decision-making regarding intracranial aneurysms. Aneurysm wall enhancement after contrast agent injection is expected to be related to aneurysm instability and rupture status. However, the authors hypothesize that slow-flow artifacts mimic aneurysm wall enhancement. Therefore, in this phantom study they assess the effect of slow flow on wall-like enhancement by using different MR VWI techniques. METHODS: The authors developed an MR-compatible aneurysm phantom model, which was connected to a pump to enable pulsatile inflow conditions. For VWI, 3D turbo spin echo sequences-both with and without motion-sensitized driven equilibrium (MSDE) and delay alternating with nutation for tailored excitation (DANTE) preparation pulses-were performed using a 3-T MR scanner. VWI was acquired both before and after Gd contrast agent administration by using two different pulsatile inflow conditions (2.5 ml/sec peak flow at 77 and 48 beats per minute). The intraluminal signal intensity along the aneurysm wall was analyzed to assess the performance of slow-flow suppression. RESULTS: The authors observed wall-like enhancement after contrast agent injection, especially in low pump rate settings. Preparation pulses, in particular the DANTE technique, improved the performance of slow-flow suppression. CONCLUSIONS: Near-wall slow flow mimics wall enhancement in VWI protocols. Therefore, VWI should be carefully interpreted. Preparation pulses improve slow-flow suppression, and therefore the authors encourage further development and clinical implementation of these techniques.
OBJECTIVE: MR vessel wall imaging (VWI) is increasingly performed in clinical settings to support treatment decision-making regarding intracranial aneurysms. Aneurysm wall enhancement after contrast agent injection is expected to be related to aneurysm instability and rupture status. However, the authors hypothesize that slow-flow artifacts mimic aneurysm wall enhancement. Therefore, in this phantom study they assess the effect of slow flow on wall-like enhancement by using different MR VWI techniques. METHODS: The authors developed an MR-compatible aneurysm phantom model, which was connected to a pump to enable pulsatile inflow conditions. For VWI, 3D turbo spin echo sequences-both with and without motion-sensitized driven equilibrium (MSDE) and delay alternating with nutation for tailored excitation (DANTE) preparation pulses-were performed using a 3-T MR scanner. VWI was acquired both before and after Gd contrast agent administration by using two different pulsatile inflow conditions (2.5 ml/sec peak flow at 77 and 48 beats per minute). The intraluminal signal intensity along the aneurysm wall was analyzed to assess the performance of slow-flow suppression. RESULTS: The authors observed wall-like enhancement after contrast agent injection, especially in low pump rate settings. Preparation pulses, in particular the DANTE technique, improved the performance of slow-flow suppression. CONCLUSIONS: Near-wall slow flow mimics wall enhancement in VWI protocols. Therefore, VWI should be carefully interpreted. Preparation pulses improve slow-flow suppression, and therefore the authors encourage further development and clinical implementation of these techniques.
Authors: Raghav R Mattay; Jose F Saucedo; Vance T Lehman; Jiayu Xiao; Emmanuel C Obusez; Scott B Raymond; Zhaoyang Fan; Jae W Song Journal: Semin Ultrasound CT MR Date: 2021-08-01 Impact factor: 1.641
Authors: B Sannananja; C Zhu; C G Colip; A Somasundaram; M Ibrahim; T Khrisat; M Mossa-Basha Journal: AJNR Am J Neuroradiol Date: 2022-05-26 Impact factor: 4.966
Authors: Naomi Larsen; Charlotte Flüh; Sylvia Saalfeld; Samuel Voß; Georg Hille; David Trick; Fritz Wodarg; Michael Synowitz; Olav Jansen; Philipp Berg Journal: Neuroradiology Date: 2020-07-17 Impact factor: 2.804
Authors: Ashrita Raghuram; Alberto Varon; Jorge A Roa; Daizo Ishii; Yongjun Lu; Madhavan L Raghavan; Chaorong Wu; Vincent A Magnotta; David M Hasan; Timothy R Koscik; Edgar A Samaniego Journal: Sci Rep Date: 2021-09-15 Impact factor: 4.379