PT  - JOURNAL ARTICLE
AU  - Zhang, Qianqian
AU  - Shao, Qiuji
AU  - Chang, Kaitao
AU  - Sheng, Zhiyuan
AU  - Zhang, Hongyun
AU  - Chen, Yi
AU  - He, Ying-Kun
AU  - Li, Tianxiao
AU  - Li, Li
TI  - A Proposed Grading Scale Based on Radiographic Imaging for Wall Apposition to Estimate Neurological Complications after Flow Diverter Treatment
AID  - 10.3174/ajnr.A8785
DP  - 2025 Apr 10
TA  - American Journal of Neuroradiology
PG  - ajnr.A8785
4099  - http://www.ajnr.org/content/early/2025/04/10/ajnr.A8785.short
4100  - http://www.ajnr.org/content/early/2025/04/10/ajnr.A8785.full
AB  - BACKGROUND AND PURPOSE: The evaluation of wall apposition following flow diverter (FD) treatment remains poorly defined. This study aims to establish a radiographic grading scale for wall apposition after FD deployment and to investigate its association with FD-related neurological complications.MATERIALS AND METHODS: This retrospective study included patients treated with the Pipeline Embolization Device (PED). A wall apposition grading scale (Grades I–IV) was developed based on radiographic imaging, incorporating anatomical location and the degree of malapposition: Grade I, perfect wall apposition; Grade II, mild malapposition; Grade III, moderate malapposition; and Grade IV, severe malapposition. Cases were categorized into two groups: complete wall apposition (Grade I) and malapposition (Grades II–IV). The association between malapposition and neurological complications was further analyzed.RESULTS: A total of 197 PED cases were included. Incomplete wall apposition was observed in 29 cases (14.7%), while 168 cases (85.3%) demonstrated complete wall apposition (Grade I). In the malapposition group, 13 cases (6.6%) were classified as Grade II, 11 cases (5.6%) as Grade III, and 5 cases (2.5%) as Grade IV. FD-related perioperative and follow-up neurological complications occurred in 10.3% and 13.8% of the malapposition group, respectively, compared to 1.8% and 1.2% in the complete wall apposition group (P<0.05). Multivariate logistic regression analysis identified malapposition as an independent risk factor for FD-related neurological complications (P<0.05). The Cochran-Armitage test revealed a significant trend of increasing neurological complications with worsening malapposition from Grade II to IV (P<0.05).CONCLUSIONS: The proposed grading scale is a feasible and practical tool for assessing wall apposition following FD treatment. Neurological complications are significantly more likely in cases with moderate to severe malapposition (Grades III and IV).ABBREVIATIONS: FD = flow diverter; PED = Pipeline Embolization Device; 2D DSA = two-dimensional digital subtraction angiography; OCT = optical coherence tomography; TIA = transient ischemic attack; IQR = interquartile range.