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

Ya-Che Chen; Fu-Chi Yang; Guo-Shu Huang; Wei-Chou Chang; Yi-Chih Hsu

doi:10.1016/j.neurad.2023.09.006

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

J Neuroradiol. 2024 Mar;51(2):204-209. doi: 10.1016/j.neurad.2023.09.006. Epub 2023 Sep 26.

Authors

Ya-Che Chen¹, Fu-Chi Yang², Guo-Shu Huang³, Wei-Chou Chang¹, Yi-Chih Hsu⁴

Affiliations

¹ Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, No. 325, Sec. 2, Chenggong Rd., Neihu Dist. 114, Taipei, Taiwan.
² Department of Neurology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
³ Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, No. 325, Sec. 2, Chenggong Rd., Neihu Dist. 114, Taipei, Taiwan; Department of Medical Research, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
⁴ Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, No. 325, Sec. 2, Chenggong Rd., Neihu Dist. 114, Taipei, Taiwan. Electronic address: doc31578@gmail.com.

PMID: 37758171
DOI: 10.1016/j.neurad.2023.09.006

Abstract

Background and purpose: 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.

Materials and methods: 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.

Results: 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).

Conclusion: 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.

Keywords: Epidural puncture; Low-CSF-pressure headache; Spontaneous intracranial hypotension; Targeted CT-guided epidural blood patching.

MeSH terms

Blood Patch, Epidural* / methods
Headache
Humans
Punctures*
Retrospective Studies
Tomography, X-Ray Computed