Cross-sectional CT Assessment of the Extent of Injectate Spread at CT Fluoroscopy-guided Cervical Epidural Interlaminar Steroid Injections.


Background Previous studies analyzed contrast agent spread during cervical interlaminar epidural steroid injections (CILESIs) by using planar fluoroscopy and reported wide variance of the rate of spread to the ventral epidural space (VES). Cross-sectional CT allows for direct viewing of contrast agent in the VES, providing improved spread assessment and thereby informing needle placement decisions when targeting pain generators. Purpose To determine the extent of injectate spread at CT fluoroscopy-guided CILESI, with particular attention to the VES and bilateral neuroforamina, by using cross-sectional CT. Materials and Methods This study reviewed 83 consecutive CT fluoroscopy-guided CILESIs at which a postprocedural cervical spine CT was performed (June 2016 to December 2017). All procedures used the same injectate (2 mL corticosteroid, 3 mL contrast agent). Postprocedural CT scans were reviewed for the presence of contrast within the VES, dorsal epidural space, ipsilateral neuroforamen, and contralateral neuroforamen in every cervical interlaminar level. Descriptive data are presented as frequencies or means. McNemar tests or hierarchical logistic models were used to assess associations between covariates and contrast agent spread to particular locations. Results The study cohort included 73 individual patients (59% women; 43 of 73) (mean patient age, 57.6 years ± 11.5 [standard deviation]). Mean number of levels of cranial spread were 0.6 level for VES, 1.9 levels for contralateral neuroforamen, 2.1 levels for ipsilateral neuroforamen, and 3 levels for dorsal epidural space. No VES spread in any level was found with 35% (29 of 83) of injections. VES spread was more likely to occur in the level of needle placement (43%; 36 of 83) than in other interlaminar levels (19.5%; 97 of 498; P < .001). Spread was more likely to occur in the neuroforamen ipsilateral to the needle approach compared with contralateral (P < .001). Conclusion Cervical interlaminar epidural steroid injections have injectate spreads with a mean of less than one level cranially in the ventral epidural space (VES) and approximately two levels in the neuroforamen. VES spread occurs more frequently at the level of needle placement and within the ipsilateral neuroforamen. © RSNA, 2019.






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Publication Info

Amrhein, Timothy J, Erol Bozdogan, Sunit Vekaria, Prasad Patel, Reginald Lerebours, Sheng Luo and Peter G Kranz (2019). Cross-sectional CT Assessment of the Extent of Injectate Spread at CT Fluoroscopy-guided Cervical Epidural Interlaminar Steroid Injections. Radiology. p. 182795. 10.1148/radiol.2019182795 Retrieved from

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Timothy James Amrhein

Associate Professor of Radiology

Dr. Amrhein is an Associate Professor in the Department of Radiology at Duke University Medical Center where he also serves as the Director of Spine Intervention. He completed residency training in Diagnostic Radiology at Duke, where he served as chief resident, and stayed to complete a Neuroradiology fellowship.


Reginald (Gino) Lerebours

Biostatistician II

Education: Masters Degree, Biostatistics. Harvard University. 2017
Bachelors Degree, Statistics. North Carolina State University. 2015

Overview:  Gino currently collaborates with researchers, residents, and clinicians in the Departments of Surgery, Radiology and Infectious Diseases. His main research interests and experience are in statistical programming, data management, statistical modeling, statistical consulting and statistical education.


Sheng Luo

Professor of Biostatistics & Bioinformatics

Peter George Kranz

Associate Professor of Radiology

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