Value of CT in targeted CT-guided epidural blood patching: Predictors for successful epidural punctures

• Published in: Journal of neuroradiology 2024-03, Vol.51 (2), p.204-209
• Main Authors: Chen, Ya-Che, Yang, Fu-Chi, Huang, Guo-Shu, Chang, Wei-Chou, Hsu, Yi-Chih
• Format: Article
• Language: English
• Subjects: Epidural puncture; Low-CSF-pressure headache; Spontaneous intracranial hypotension; Targeted CT-guided epidural blood patching
• ISSN: 0150-9861
• DOI: 10.1016/j.neurad.2023.09.006

Differentiating epidural from intrathecal punctures before computed tomography (CT)-guided epidural blood patching (EBP) is subjective, relying on operator experience. This study aimed to investigate CT findings for epidural and intrathecal punctures and identify reliable predictors for successful epidural punctures before targeted CT-guided EBP. We included 65 patients with low-cerebrospinal fluid (CSF)-pressure headache receiving targeted CT-guided EBP between January 2021 and October 2022 in this retrospective study. We analyzed clinical data, technical information, and CT features before EBP. Fisher's exact test was used for discrete variables, while Mann–Whitney U test was used for continuous variables. Positive (PLR) and negative likelihood ratios (NLR) were calculated to identify predictors for confirming epidural punctures. We confirmed 43 patients as epidural punctures and 22 patients as intrathecal punctures. Before contrast injection, epidural fat at the needle tip in the epidural group was higher than the intrathecal group (37.2 % [16/43] vs. 4.5 % [1/22], p = 0.006). After contrast injection, the “contrast-needle tip connection” sign was mostly observed in the epidural group than the intrathecal group (95.3 % [41/43] vs. 9.1 % [2/22], p < 0.001). Additionally, the epidural group had significantly higher boomerang-shaped contrast morphology than the intrathecal group (65.1 % [28/43] vs. 9.1 % [2/22], p < 0.001). The “contrast-needle tip connection” sign had the highest PLR (10.49) and lowest NLR (0.05). Identifying epidural fat at the needle tip, “contrast-needle tip connection” sign, and boomerang-shaped contrast morphology on CT scans are useful for confirming proper placement of the needle tip within the epidural space. [Display omitted] •Epidural blood patching (EBP) is effective for spontaneous intracranial hypotension (SIH).•Computed tomography (CT)-guided EBP can achieve targeted epidural punctures.•Differentiating between epidural and intrathecal punctures before targeted CT-guided EBP may be challenging.•Visible epidural fat at needle tip and boomerang-shaped contrast morphology are specific signs for confirming epidural punctures.•The “contrast-needle tip connection” sign is a reliable predictor for successful epidural punctures.