Image Guidance and Contrast in Spinal Injections
Most spinal injections in pain medicine are done with fluoroscopy, a live X-ray that shows the needle and the bones of the spine in real time. Before medication is injected, a small amount of contrast dye is often injected to show where the fluid goes. The goal is to confirm that the needle is where it should be and is not in a blood vessel, in the spinal fluid space, or in the wrong tissue.
When a spinal injection goes wrong, the saved images are often some of the most important records. They can show a great deal, but they also have limits. This article explains how image guidance and contrast are used for safety, and how a physician reads them when care is reviewed.
Why image guidance matters
Without imaging, a needle's position near the spine is estimated from feel and surface landmarks. With fluoroscopy, the physician can confirm the level, the side, and the needle's depth. Contrast then shows the pattern of spread. Spread in the epidural space looks different from spread in the spinal fluid, in a blood vessel, or in muscle.
The 2015 consensus safeguards for epidural steroid injections, developed by a multidisciplinary working group with the U.S. Food and Drug Administration's Safe Use Initiative and 13 specialty societies (Rathmell and colleagues, Anesthesiology, 2015), include the use of radiographic guidance among their clinical considerations for transforaminal and interlaminar injections. A 2026 review Dr. Urits co-authored on transforaminal injections (Hasoon and colleagues, Orthopedic Reviews) states that careful review of imaging beforehand, fluoroscopic guidance, contrast injection, and preferential use of nonparticulate steroid remain essential regardless of the approach used.
Views: seeing depth as well as position
A straight-on (front-to-back) view shows side-to-side position but not depth. Depth views, such as the lateral view and the contralateral oblique view, show how far the needle has advanced toward the spinal canal.
Dr. Urits is the author of Diagrammatic Analysis of Subarachnoid Contrast Spread in the Contralateral Oblique View: A Technical Report (Pain Management Case Reports, 2018), which addresses how contrast in the spinal fluid space appears in that view. He also co-authored a survey of spinal cord stimulator lead placement practices (Gill and colleagues, Anesthesiology and Pain Medicine, 2022). In that survey, 45% of respondents "always used" the lateral view and 15% "always used" the contralateral oblique view for lead insertion, while 65% used the contralateral oblique view with varying frequency. The authors concluded that a depth view was always used by only 45% to 60% of respondents and that the contralateral oblique view had been rapidly adopted.
Practice patterns like these help show what reasonable physicians were doing at the time. They do not, by themselves, set the standard of care.
What contrast can reveal
- Intravascular spread. Contrast that quickly washes away or outlines a vessel suggests the needle is in a vein or artery. Injecting medication there can be dangerous, especially with particulate steroid near arteries that supply the spinal cord or brain.
- Intrathecal spread. Contrast in the spinal fluid space suggests the dura has been punctured. Injecting a large dose of local anesthetic there can cause a high or total spinal block.
- Epidural spread. A typical epidural pattern supports correct placement.
- Spread outside the target. Contrast in muscle or other tissue may mean the needle needs repositioning.
Contrast also has limits. A brief intravascular flow can be missed, especially with a single static image. Some physicians use live or digital subtraction imaging to improve detection in higher-risk injections. Patients with contrast allergies may need an alternative plan, which should be documented.
Beyond injections: other image-guided procedures
Image guidance is also central to procedures such as kyphoplasty and spinal cord stimulator placement. Dr. Urits is the author of Epidural Cement Leakage During Kyphoplasty Leading to Radiculopathy (Pain Management Case Reports, 2019), a case report describing how cement leaking into the epidural space caused nerve root symptoms.
What saved images can and cannot show
Saved images are a snapshot. A case review should recognize what they do and do not prove.
- They can show the level, the side, final needle position, and contrast pattern at the moment each image was saved.
- They may not show what happened between saved images, how long contrast was observed, whether live fluoroscopy was used, or the needle position at the moment the medication was injected.
- Missing images may mean images were not saved, were not exported, or were lost. The complete imaging file, including metadata such as timestamps and radiation dose reports, can fill some gaps.
An expert should compare the images with the procedure note. If the note says contrast confirmed epidural spread, do the images show it? If the note mentions repositioning, is that visible?
Standard-of-care questions an expert asks
- Was fluoroscopy or another appropriate image guidance used?
- Were appropriate views obtained, including a depth view where relevant?
- Was contrast injected before the medication, and was the pattern interpreted correctly?
- Was the plan adjusted when contrast showed vascular or intrathecal spread?
- Were images saved, and does the procedure note match them?
- Were contrast allergies identified and addressed?
Records that usually matter
- The complete saved fluoroscopic image set, with metadata and timestamps
- The procedure note describing views, contrast, and any repositioning
- Pre-procedure MRI or CT used for planning
- Allergy history and any premedication
- Facility imaging and radiation safety policies on the date of care
Key takeaways
- Fluoroscopy and contrast are central safety tools in spinal injections.
- Depth views and contrast patterns help detect misplaced, intravascular, or intrathecal needle position.
- Saved images are valuable records, but they are only snapshots.
- The analysis compares images, the procedure note, and published guidance in effect at the time.
References
- Rathmell JP, Benzon HT, Dreyfuss P, et al. Safeguards to prevent neurologic complications after epidural steroid injections: consensus opinions from a multidisciplinary working group and national organizations. Anesthesiology. 2015;122(5):974-984. Abstract: https://pubmed.ncbi.nlm.nih.gov/25668411/
- Hasoon J, Robinson CL, Yazdi C, Urits I, Kaye AD. The Infraneural Approach to Lumbar Transforaminal Epidural Steroid Injections: A Practical Review for Trainees and Interventionalists. Orthop Rev (Pavia). 2026;18:166794. Abstract: https://pubmed.ncbi.nlm.nih.gov/42631325/
- Urits I. Diagrammatic Analysis of Subarachnoid Contrast Spread in the Contralateral Oblique View: A Technical Report. Pain Management Case Reports. 2018. doi:10.36076/pmcr.2018/2/141. DOI: https://doi.org/10.36076/pmcr.2018/2/141 (not indexed in PubMed)
- Gill J, Kohan L, Hasoon J, et al. Contralateral and Lateral Views: Analysis of the Technical Aspects of Spinal Cord Stimulator Lead Insertion. Anesth Pain Med. 2022;12(1):e123357. Abstract: https://pubmed.ncbi.nlm.nih.gov/35433387/
- Urits I. Epidural Cement Leakage During Kyphoplasty Leading to Radiculopathy. Pain Management Case Reports. 2019. doi:10.36076/pmcr.2019/3/191. DOI: https://doi.org/10.36076/pmcr.2019/3/191 (not indexed in PubMed)
Related: Interventional Procedure Complication Cases
Educational information only. Not legal or medical advice.
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