Scholarlink

Purpose <p>Digital subtraction angiography (DSA) is the gold standard for evaluating outcomes after flow diverter (FD) stent placement, though its invasive nature presents limitations. Time-of-flight magnetic resonance angiography (TOF-MRA) is commonly used as a&#xa0;non-invasive alternative; however, it is susceptible to artifacts related to magnetic susceptibility and phase dispersion. Recently, Pointwise Encoding Time Reduction with Radial Acquisition (PETRA)-MRA, which employs an ultra-short echo time technique, has emerged as a&#xa0;promising option for post-endovascular imaging. This study aimed to quantitatively assess and compare the signal properties of PETRA-MRA and TOF-MRA in patients following FD treatment, in order to minimize observer-dependent variability.</p> Methods <p>A&#xa0;retrospective review was conducted on patients treated with a&#xa0;Pipeline Flex with Shield Technology stent for internal carotid artery aneurysms between April 2021 and March 2024. All patients underwent both TOF-MRA and PETRA-MRA scans on the day after treatment, using a&#xa0;3‑T MRI system. Signal intensities were evaluated in the FD, contralateral internal carotid artery (ICA), aneurysm, and background across three slices for each patient. For aneurysm analysis, the slice with the largest visible aneurysm diameter was selected. Contrast-to-noise ratios (CNR) were computed in relation to the background signal, and signal intensity ratios (SIR) were calculated with reference to the contralateral ICA. These metrics were then compared between TOF-MRA and PETRA-MRA.</p> Results <p>The analysis included 21&#xa0;patients (mean age 60.2 years; 14&#xa0;female), with 7 (33%) receiving additional coiling. The average aneurysm diameter was 9.2 ± 5.6 mm. PETRA-MRA yielded significantly higher CNR values for both the FD (3.80 ± 1.21) and aneurysm (8.04 ± 5.79) compared with TOF-MRA (FD 2.51 ± 0.95, <i>p</i> &lt; 0.001; aneurysm 3.92 ± 2.41, <i>p</i> = 0.001). Similarly, SIR values were notably greater with PETRA-MRA for the FD (0.44 ± 0.07 vs. 0.35 ± 0.08, <i>p</i> &lt; 0.001) and the aneurysm (0.95 ± 0.19 vs. 0.62 ± 0.23, <i>p</i> &lt; 0.001).</p> Conclusions <p>Compared to TOF-MRA, PETRA-MRA provided higher CNR and SIR in the evaluation of both FD and aneurysm visualization. These findings indicate that PETRA-MRA is a&#xa0;promising noninvasive technique for early postprocedural assessment after FD treatment.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Quantitative Assessment of Signal Intensity in PETRA-MRA Vs. TOF-MRA After Flow Diverter Stent Placement

  • 期刊论文

  • 发表日期：

    2026年1月8日

查看全文
  • Yosuke Ishii,
  • Toshihiko Hayashi,
  • Haruna Furuya,
  • So Akutsu,
  • Aya Namba,
  • Shigeru Nemoto

摘要

Purpose

Digital subtraction angiography (DSA) is the gold standard for evaluating outcomes after flow diverter (FD) stent placement, though its invasive nature presents limitations. Time-of-flight magnetic resonance angiography (TOF-MRA) is commonly used as a non-invasive alternative; however, it is susceptible to artifacts related to magnetic susceptibility and phase dispersion. Recently, Pointwise Encoding Time Reduction with Radial Acquisition (PETRA)-MRA, which employs an ultra-short echo time technique, has emerged as a promising option for post-endovascular imaging. This study aimed to quantitatively assess and compare the signal properties of PETRA-MRA and TOF-MRA in patients following FD treatment, in order to minimize observer-dependent variability.

Methods

A retrospective review was conducted on patients treated with a Pipeline Flex with Shield Technology stent for internal carotid artery aneurysms between April 2021 and March 2024. All patients underwent both TOF-MRA and PETRA-MRA scans on the day after treatment, using a 3‑T MRI system. Signal intensities were evaluated in the FD, contralateral internal carotid artery (ICA), aneurysm, and background across three slices for each patient. For aneurysm analysis, the slice with the largest visible aneurysm diameter was selected. Contrast-to-noise ratios (CNR) were computed in relation to the background signal, and signal intensity ratios (SIR) were calculated with reference to the contralateral ICA. These metrics were then compared between TOF-MRA and PETRA-MRA.

Results

The analysis included 21 patients (mean age 60.2 years; 14 female), with 7 (33%) receiving additional coiling. The average aneurysm diameter was 9.2 ± 5.6 mm. PETRA-MRA yielded significantly higher CNR values for both the FD (3.80 ± 1.21) and aneurysm (8.04 ± 5.79) compared with TOF-MRA (FD 2.51 ± 0.95, p < 0.001; aneurysm 3.92 ± 2.41, p = 0.001). Similarly, SIR values were notably greater with PETRA-MRA for the FD (0.44 ± 0.07 vs. 0.35 ± 0.08, p < 0.001) and the aneurysm (0.95 ± 0.19 vs. 0.62 ± 0.23, p < 0.001).

Conclusions

Compared to TOF-MRA, PETRA-MRA provided higher CNR and SIR in the evaluation of both FD and aneurysm visualization. These findings indicate that PETRA-MRA is a promising noninvasive technique for early postprocedural assessment after FD treatment.