Contrast flow characteristics in the cervical epidural space: an analysis of cervical epidurograms

Comparative analysis of contrast distribution in cervical epidural steroid injections utilizing a modified paramedian interlaminar approach with varied needle tip positions: A randomized controlled trial

BACKGROUND

Recent advancements in cervical interlaminar epidural steroid injections have given rise to the modified paramedian interlaminar (mPIL) approach. The objective of this study was to perform an analysis of the contrast spread pattern within the cervical epidural space, taking into account different needle tip positions in the mPIL approach.

METHODS

A total of 48 patients were included in the study and randomly assigned to either the medial or lateral group based on the needle tip's position in the anterior-posterior view. The primary outcome measured was the contrast flow under fluoroscopic visualization. As a secondary outcome, we analyzed the location of the needle tip position in both lateral and contralateral oblique views. Clinical effectiveness was assessed by measuring pain intensity and functional disability post-procedure.

RESULTS

Significant disparities were noted in the ventral distribution of contrast between the medial and lateral groups. In the lateral images, needle tips in the lateral group were positioned more ventrally compared to those in the medial group. Both groups exhibited statistically significant improvements in neck and radicular pain, as well as functional status, 4 weeks after treatment, with no significant differences between them.

CONCLUSIONS

Our results suggest that the ventral dispersion of contrast material during cervical interlaminar epidural steroid injections using the mPIL approach may vary depending on the needle tip location.

Ultrasound: A novel alternative technique for cervical epidural space visualization-A pilot study

Background

Neuraxial ultrasound (US), a newer modality, can be used for neuraxial imaging, helping in visualizing and aiding in epidural space catheterization. The aim of this study was to evaluate the efficacy of the US for cervical epidural access and to determine the failure rate and complication associated with this technique.

Methods

A prospective single-arm pilot study was conducted on 21 participants. The neuraxial US image quality assessment by Ultrasound Visibility Score (UVS), epidural space depth measurement by US and by conventional loss of resistance (LOR) technique, and post-procedure epidural catheter confirmation by real-time US were the study parameters. Any procedural complications or failure rate were recorded. The Kolmogorov-Smirnov test, paired-samples t-test, and Chi-square test were used for the statistical comparison.

Results

The pre-procedural UVS by the transverse interlaminar view (x/21) was 2.81 ± 1.94 and by the oblique paramedian sagittal view was 16.66 ± 2.39 with UVS being best in the paramedian oblique sagittal view (P- value < 0.05). The comparison of depth of the epidural space identified by USG and that by the LOR technique was statistically insignificant (P = 0.83). The average puncture attempts were 1.1 ± 0.3. Post-procedure US epidural catheter confirmation score (x/3) was 1.44 ± 0.44 with either epidural space expansion or microbubbles seen or both.

Conclusion

The pilot study has successfully demonstrated the implication of US for visualizing and aiding in epidural space catheterization. Also, the failure rate and procedural complications were drastically minimized with the help of US as compared to the traditional blind technique.

Prediction of the Cervical Epidural Space Depth from the Skin Using Cervical X-Ray, During Cervical Epidural Block with Paramedian Approach

Objective

The purpose of this study is to compare the actual needle depth measured during cervical epidural block (CEB) with the predicted needle depth measured through a cervical flexion x-ray image at the paramedian approach.

Methods

The study was conducted based on the medical records of patients who underwent CEB at the pain clinic of Haeundae Paik Hospital. The actual needle distance (AD) was recorded after each successful CEB. The distance from the spinolaminar line to the skin, predicted median depth (PMD), was measured using lateral x-ray images. The medial to lateral distance (MLD), which is the distance from the midline of the spine to the needle insertion point, was measured using anteroposterior (AP) x-rays. The predicted paramedian depth (PPD) was calculated using the Pythagorean formula. The PMD represents the expected depth of the median approach, while the PPD represents the expected depth of the paramedian approach. The PMD, PPD, and AD were compared with each other.

Results

Concordance correlation coefficient (CCC) and Bland-Altman analysis were obtained for PMD and PPD. The CCC value of PMD was measured as 0.829, and the CCC value of PPD was measured as 0.830. In the Bland-Altman analysis, PPD was measured at -0.13 ± 8.37 mm, and PMD was measured at 1.29 ± 8.38 mm.

Conclusion

When performing CEB through the paramedian approach, the depth can be predicted using a cervical flexion x-ray. At this time, the PMD can also be used to predict the depth during the paramedian approach.

Interventional Pain Procedures: A Narrative Review Focusing on Safety and Complications. Part 1 Injections for Spinal Pain

In recent years, there has been a considerable increase in the number of image-guided interventional procedures performed for the management of acute and chronic pain. Concomitantly, there has also been an increase in the complication rate related to these procedures. The aim of this narrative review is to summarize the primary complications associated with commonly performed image-guided (fluoroscopic- or ultrasound-guided) interventional procedures. We conclude that although complications from interventional pain procedures can be mitigated to a certain degree, they cannot be eliminated altogether. In order to avoid adverse events, patient safety should be given considerable attention and physicians should be constantly aware of the possibility of developing complications.

An open-label non-inferiority randomized trail comparing the effectiveness and safety of ultrasound-guided selective cervical nerve root block and fluoroscopy-guided cervical transforaminal epidural block for cervical radiculopathy

OBJECT

To compare therapeutic efficacy and safety of ultrasound (US)-guided selective nerve root block (SNRB) and fluoroscopy (FL)-guided transforaminal epidural steroid injection (TFESI) for cervical spine radiculopathy (CSR).

METHOD

156 patients with CSR randomly received US-guided SNRB verified by FL or FL-guided TFESI. We hypothesised that the accuracy rate of contrast dispersion into epidural or intervertebral foraminal space in the US group was not inferior to that in the FL group with a margin of clinical unimportance of -15%. Pain intensity assessed by Numeric Rating Scales (NRS) and functional disability estimated by neck disability index (NDI) were compared before treatment, at 1, 3 and 6 months after the intervention. Puncture time and complication frequencies were also reported.

RESULTS

88.7% and 90.3% accuracy ratings were respectively achieved in the US and FL groups with a treatment difference of -1.6% (95%CI: -9.7%, 6.6%) revealing that the lower limit was above the non-inferiority margin. Both NRS and NDI scores illustrated improvements at 1, 3 and 6 months after intervention with no statistically significant differences between the two groups (all p > .05). Additionally, shorter administration duration was observed in the US group (p < .001). No severe complications were observed in both group.

CONCLUSION

Compared with the FL group, the US group provided a non-inferior accuracy rate of epidural/foraminal contrast pattern. For the treatment of CSR, the US technique provided similar pain relief and functional improvements while facilitating distinguishing critical vessels adjacent to the foramen and requiring a shorter procedure duration without exposure to radiation. Therefore, it was an attractive alternative to the conventional FL method.Key messagesWe conducted a prospective, open-label, randomised and non-inferiority clinical trial to estimate a hypothesis that the precisely accurate delivery through ultrasound (US)-guided cervical selective nerve root block (SNRB) was non-inferior to that using FL-guided transforaminal epidural steroid injection. Additionally, US-guided SNRB was as effective as FL-guided TFESI in the treatment effect on pain relief and function improvements. Notably, the US technique might be an alternative to the conventional FL method due to the ability to prevent inadvertent vascular puncture (VP) and intravascular injection (IVI) with a shorter administration time and absence of radiation exposure.

Evaluation of Contrast Flow Patterns with Cervical Interlaminar Epidural Injection: Comparison of Midline and Paramedian Approaches

Background and objectives: The purpose of this study was to compare and to analyze contrast spread patterns between the paramedian and midline approaches to cervical interlaminar epidural injection (CIEI). Materials and Methods: We retrospectively enrolled 84 CIEI cases that had been performed for unilateral cervical spinal pain from April 2019 to April 2020. After 3 mL of contrast had been injected into the epidural space, fluoroscopic images were obtained. The CIEI was divided into a midline (Group M, n = 42) and a paramedian (Group P, n = 42) approach by anteroposterior imaging. The P Group was classified into a more medial (Group Pm, n = 26) and a more lateral (Group Pl, n = 16) group. Using ImageJ on an anteroposterior image, we assessed the grayscale brightness ratio of the ipsilateral or contralateral side of the vertebral body as well as the intervertebral disc space one level just above the needle location. We identified the dispersion of contrast into the ventral epidural space. Results: The grayscale brightness ratio was significantly higher in Group P than in Group M (p < 0.001). The incidence of ventral epidural spread in Group M was 57.1% versus 88.1% in Group P, which was significantly different (p = 0.001). Conclusions: The fluoroscopic CIEI finding in the paramedian approach predominantly showed an excellent delivery of the injectate to the ipsilateral side in comparison to the contralateral side. This showed a greater advantage in delivery toward ventral epidural space as compared to the midline approach.

Complications of Fluoroscopically Guided Cervical Interlaminar Epidural Steroid Injections

PURPOSE OF REVIEW

Cervical interlaminar epidural steroid injection is a common intervention in the management of cervical radiculitis. Given the large number of injections done annually, it is important to assess the potential complications associated with this procedure.

RECENT FINDINGS

Based on current published studies, the overall complication rate varies. The vast majority are minor complications. However, this review also identified potentially catastrophic complications following cervical interlaminar epidural steroid injections. Based upon our review, cervical epidural steroid injection is considered a safe intervention. Nevertheless, catastrophic complications such as spinal cord injuries from needle placement, infections, and epidural hematoma can occur. It is prudent to take appropriate measures to minimize these complications.

A Randomized Comparative Trial of Targeted Steroid Injection via Epidural Catheter vs Standard Transforaminal Epidural Injection for the Treatment of Unilateral Cervical Radicular Pain: Six-Month Results

Objectives

Compare the effectiveness of catheter-directed cervical interlaminar epidural steroid injection (C-CIESI) with triamcinolone to cervical transforaminal steroid injection (CTFESI) with dexamethasone for the treatment of refractory unilateral radicular pain.

Design

Prospective, randomized, comparative trial.

Methods

Primary outcome: proportion of participants with ≥50% numeric rating scale pain score reduction from baseline “dominant pain” (the greater of arm vs neck) at one month postinjection. Secondary outcomes: ≥30% Neck Disability Index (NDI-5) reduction and Patient Global Impression of Change (PGIC) response indicating “much improved” or “very much improved.”

Results

One hundred twenty participants (55.6% females, 52.3 ± 12.5 years of age, BMI 28.2 ± 6.5 kg/m2), were enrolled. The proportions of participants who experienced ≥50% pain reduction at one, three, and six months were 68.5% (95% CI = 54.9–79.5%), 59.3% (95% CI = 45.7–71.6%), and 60.8% (95% CI = 46.7–73.2%), respectively, in the C-CIESI group compared with 49.1% (95% CI = 36.4–62.0%), 46.4% (95% CI = 33.8–59.6%), and 51.9% (95% CI = 38.4–65.2%), respectively, in the CTFESI group. The between-group difference at one month was significant (P = 0.038). The proportions of participants who experienced a ≥30% NDI-5 score improvement were 64.0% (95% CI = 49.8–76.1%) and 54.9% (95% CI = 41.1–68.0%) in the C-CIESI and CTFESI groups (P = 0.352). Participants reported similar PGIC improvement in both groups: At six months, 53.2% (95% CI 38.9–67.1%) and 54.5% (95% CI = 39.7–68.7%) of the C-CIESI and CTFESI groups reported being “much improved” or “very much improved,” respectively (P = 0.897).

Conclusions

Both C-CIESI with triamcinolone and CTFESI with dexamethasone are effective in reducing pain and disability associated with refractory unilateral cervical radiculopathy in a substantial proportion of participants for at least six months.

Effect of low-dose lidocaine on objective upper extremity strength and immediate pain relief following cervical interlaminar epidural injections: a double-blinded randomized controlled trial

Background

Low-dose lidocaine is a common diluent for analgesia following cervical interlaminar epidural steroid injection (CIESI). Concerns with this practice exist. A single-arm cohort reported that 20% of patients develop postprocedural upper extremity weakness when using lidocaine as a diluent. Furthermore, a high-cervical spinal block with unintended intrathecal or subdural administration is possible.

Objective

Determine if low-dose lidocaine as a diluent during CIESI causes clinically meaningful (1) upper extremity weakness and (2) immediate pain relief when compared with saline.

Design

Double-blinded randomized control trial.

Methods

Patients with cervical radicular pain scheduled for CIESI were enrolled. Participants received lidocaine (CIESI-L) or saline (CIESI-S) as a diluent for the epidural injectate. Myotomal strength was measured with dynamometry before and between 20 and 30 min after CIESI. Pre-pain and post-pain scores were obtained. Primary and secondary outcomes were post-CIESI weakness of ≥20% (minimal clinically important difference (MCID)) in >1 myotome and ≥50% pain reduction on the numerical scale.

Results

120 participants (64 females (53%), mean age, 56 (SD 13.7) years) completed the study and were analyzed (CIESI-L n=60; CIESI-S n=60). There was no significant between-group difference in the proportion of participants with postprocedural weakness, CIESI-L 41.7% (95% CI, 29.8% to 54.5%), CIESL-S 50% (95% CI, 37.5% to 62.5%). Between-group comparison showed no significant difference in pain reduction, relative risk 1.53 (95% CI, 0.82 to 2.86).

Conclusion

Low-dose lidocaine as a diluent in CIESI does not significantly increase the risk of post-CIESI myotomal weakness when compared with saline, but also does not substantially increase the likelihood of immediate, meaningful pain relief.

Trial registration details

ClinicalTrials.gov (NCT03127137); December 26, 2017.

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.

Dispersal Pattern of Injectate After Cervical Epidural Steroid Injection Evaluated With Magnetic Resonance Imaging

STUDY DESIGN

Prospective, nonrandomized, clinical study.

OBJECTIVE

Epidural steroid injections (ESIs) are an important diagnostic and treatment modality for spine pathology. The success of these injections has been attributed to the anatomic location reached by the injectate. This study evaluates injectate dispersal patterns after cervical interlaminar ESI using magnetic resonance imaging (MRI).

METHODS

Patients between the ages of 18 and 85 years with cervical radiculopathy were identified. After obtaining consent for study participation, a gadolinium-enhanced cervical ESI was administered via an interlaminar approach under fluoroscopic guidance. Study participants underwent a cervical spine MRI within 15 minutes of administering the injection. Craniocaudal dispersal and the presence or absence of circumferential dispersal was assessed.

RESULTS

The injectate dispersed a mean of 8.11 cm in the cranial direction, 6.63 cm in the caudal direction, and 360° circumferentially. No adverse events related to the ESI were reported.

CONCLUSIONS

Fluoroscopy-guided cervical interlaminar ESI resulted in nearly uniform circumferential dispersal within the epidural space with multilevel migration in the cranial and caudal directions. MRI is a safe and accurate tool to evaluate spinal injectate dispersal.

Safe Use of Epidural Corticosteroid Injections: Recommendations of the WIP Benelux Work Group

BACKGROUND

Epidural corticosteroid injections are used frequently worldwide in the treatment of radicular pain. Concerns have arisen involving rare major neurologic injuries after this treatment. Recommendations to prevent these complications have been published, but local implementation is not always feasible due to local circumstances, necessitating local recommendations based on literature review.

METHODS

A work group of 4 stakeholder pain societies in Belgium, The Netherlands, and Luxembourg (Benelux) has reviewed the literature involving neurological complications after epidural corticosteroid injections and possible safety measures to prevent these major neurologic injuries.

RESULTS

Twenty-six considerations and recommendations were selected by the work group. These involve the use of imaging, injection equipment particulate and nonparticulate corticosteroids, epidural approach, and maximal volume to be injected.

CONCLUSION

Raising awareness about possible neurological complications and adoption of safety measures recommended by the work group aim at reducing the risks for these devastating events.

Preliminary study on contrast flow analysis of thoracic transforaminal epidural block

Background

The thoracic transforaminal epidural block (TTFEB) is usually performed to treat herpes zoster or postherpetic neuralgia (PHN). Especially, multiple segmental involvements and approximate contrast medium spread range, according to volume, help to choose the proper drug volume in the transforaminal epidural block. This study investigated the contrast medium spread patterns of 1-ml to 3-ml TTFEBs.

Methods

A total of 26 patients with herpes zoster or PHN were enrolled in this study. All participants received 1 ml, 2 ml, or 3 ml of contrast medium. Results were divided into Groups A, B and C based on the volume (1, 2, or 3 ml), with n = 26 for each group. After the injection of contrast medium, the spread levels were estimated in both the lateral and anteroposterior (AP) images using fluoroscopy.

Results

The cephalad spread of contrast medium in the lateral image as expressed by the median (interquartile range) was 2.00 levels (1.00-2.00) for Group A, 2.50 (2.00-3.00) for Group B, and 3.00 (2.00-4.00) for Group C. The caudal spread level of contrast medium was 1.00 (1.00-2.00) for Group A, 2.00 (2.00-3.00) for Group B, and 2.00 (2.00-3.00) for Group C. There was ventral and dorsal spread of the 3-ml contrast medium injection in 88% (23/26) of cases in the lateral image.

Conclusions

Injection of 3 ml of contrast medium through the foramina spread 6 levels in a cephalocaudal direction. Spread patterns revealed a cephalad preference. TTFEB resulted in dorsal and ventral spread in a high percentage of cases. This procedure may be useful for transferring drugs to the dorsal and ventral roots.

Safety of Epidural Corticosteroid Injections

BACKGROUND AND OBJECTIVE

Epidural corticosteroid injections (ESIs) have been used for several decades and now represent the most common intervention performed for the management of back pain with a radicular component. However, several reports have presented devastating complications and adverse effects, which fuelled concerns over the risk versus clinical effectiveness. The authors offer a comprehensive review of the available literature and analyse the data derived from studies and case reports.

METHODS

Studies were identified by searching PubMed MEDLINE, Ovid MEDLINE, EMBASE, Scopus, Google Scholar and the Cochrane Library to retrieve all available relevant articles. Publications from the last 20 years (September 1994 to September 2014) were considered for further analysis. Studies selected were English-language original articles publishing results on complications related to the technique used for cervical and lumbar ESIs. The studies had to specify the approach used for injection. All studies that did not fulfil these eligibility criteria were excluded from further analysis.

RESULTS

Overall, the available literature supports the view that serious complications following injections of corticosteroid suspensions into the cervical and lumbar epidural space are uncommon, but if they occur they can be devastating.

CONCLUSIONS

The true incidence of such complications remains unclear. Direct vascular injury and/or administration of injectates intra-arterially represent a major concern and could account for the vast majority of the adverse events reported. Accurate placement of the needle, use of a non-particulate corticosteroid, live fluoroscopy, digital subtraction angiography, and familiarisation of the operator with contrast patterns on fluoroscopy should minimise these risks. The available literature has several limitations including incomplete documentation, unreported data and inherent bias. Large registries and well-structured observational studies are needed to determine the true incidence of adverse events and address the safety concerns.

Fluoroscopically Guided Epidural Injections of the Cervical and Lumbar Spine

Advances in imaging and the development of injection techniques have enabled spinal intervention to become an important tool in managing chronic spinal pain. Epidural steroid injection (ESI) is one of the most widely used spinal interventions; it directly delivers drugs into the epidural space to relieve pain originating from degenerative spine disorders-central canal stenoses and neural foraminal stenoses-or disk herniations. Knowledge of the normal anatomy of the epidural space is essential to perform an effective and safe ESI and to recognize possible complications. Although computed tomographic (CT) or combined CT-fluoroscopic guidance has been increasingly used in ESI, conventional fluoroscopic guidance is generally performed. In ESI, drugs are delivered into the epidural space by interlaminar or transforaminal routes in the cervical spine or by interlaminar, transforaminal, or caudal routes in the lumbar spine. Epidurography is usually performed before drug delivery to verify the proper position of the needle in the epidural space. A small amount of contrast agent is injected with fluoroscopic guidance. Familiarity with the findings on a typical "true" epidurogram (demonstrating correct needle placement in the epidural space) permits proper performance of ESI. Findings on "false" epidurograms (demonstrating incorrect needle placement) include muscular staining and evidence of intravascular injection, inadvertent facet joint injection, dural puncture, subdural injection, and intraneural or intradiscal injection. ^©RSNA, 2016 An earlier incorrect version of this article appeared online. This article was corrected on December 22, 2016.

Optimal volume of injectate for fluoroscopy-guided cervical interlaminar epidural injection in patients with neck and upper extremity pain

There is no study of optimal volume of contrast medium to use in cervical interlaminar epidural injections (CIEIs) for appropriate spread to target lesions. To determine optimal volume of contrast medium to use in CIEIs. We analyzed the records of 80 patients who had undergone CIEIs. Patients were divided into 3 groups according to the amount of contrast: 3, 4.5, and 6 mL. The spread of medium to the target level was analyzed. Numerical rating scale data were also analyzed. The dye had spread to a point above the target level in 15 (78.9%), 22 (84.6%), and 32 (91.4%) patients in groups 1 to 3, respectively. The dye reached both sides in 14 (73.7%), 18 (69.2%), and 23 (65.7%) patients, and reached the ventral epidural space in 15 (78.9%), 22 (84.6%), and 30 (85.7%) patients, respectively. There were no significant differences of contrast spread among the groups. There were no significant differences in the numerical rating scale scores among the groups during the 3 months. When performing CIEIs, 3 mL medication is sufficient volume for the treatment of neck and upper-extremity pain induced by lower cervical degenerative disease.

Reliability and Accuracy of MRI Laminar Angle Measurements to Determine Intra-Procedural Contralateral Oblique View Angle for Cervical or Thoracic Interlaminar Epidural Steroid Injections

BACKGROUND AND OBJECTIVE

Contralateral oblique (CLO) angle view has been a useful addition to standard views in fluoroscopically guided interlaminar epidural injections. Determination of the appropriate CLO angle is paramount in the usefulness of this technique. Using MRI laminar angle measurements as a pre-procedural guide for the intra-procedural fluoroscopic CLO angle has been proposed. The purpose of this study was to help determine if using axial MRI laminar measurements prior to a cervical or thoracic epidural steroid injection would be useful in predicting the appropriate fluoroscopic CLO angle.

STUDY DESIGN

A retrospective review was performed for patients who underwent cervical or thoracic interlaminar injections. In the performance of interlaminar injections, the authors had routinely determined the true fluoroscopic contra-lateral oblique angle after epidural access was confirmed, for use during any potential future injections. The fluoroscopic CLO angle measurements were obtained from a chart review and compared blindly to each patient's MRI axial laminar angle measurements.

RESULTS

34 injections were included. Inter-rater reliability comparing the two authors' MRI angle measurements was considered fair, ICC = 0.395. Accuracy was only 57% comparing MRI laminar angle measurements to within five degrees of the true fluoroscopic CLO angle as determined during the injection procedure. Accuracy by ICC showed only fair agreement, 0.47 and 0.22, for the two authors.

CONCLUSIONS

The findings of this study indicate fair inter-rater reliability in manual measurements of laminar angle on axial MRI images. MRI laminar angle measurements do not appear to be highly accurate in determining the appropriate fluoroscopic CLO angle.

Safeguards to Prevent Neurologic Complications after Epidural Steroid Injections

Background:

Epidural corticosteroid injections are a common treatment for radicular pain caused by intervertebral disc herniations, spinal stenosis, and other disorders. Although rare, catastrophic neurologic injuries, including stroke and spinal cord injury, have occurred with these injections.

Methods:

A collaboration was undertaken between the U.S. Food and Drug Administration Safe Use Initiative, an expert multidisciplinary working group, and 13 specialty stakeholder societies. The goal of this collaboration was to review the existing evidence regarding neurologic complications associated with epidural corticosteroid injections and produce consensus procedural clinical considerations aimed at enhancing the safety of these injections. U.S. Food and Drug Administration Safe Use Initiative representatives helped convene and facilitate meetings without actively participating in the deliberations or decision-making process.

Results:

Seventeen clinical considerations aimed at improving safety were produced by the stakeholder societies. Specific clinical considerations for performing transforaminal and interlaminar injections, including the use of nonparticulate steroid, anatomic considerations, and use of radiographic guidance are given along with the existing scientific evidence for each clinical consideration.

Conclusion:

Adherence to specific recommended practices when performing epidural corticosteroid injections should lead to a reduction in the incidence of neurologic injuries.

Epidural steroid injections: an updated review on recent trends in safety and complications

SUMMARY 

Epidural steroid injections (ESIs), which can provide significant but temporary pain relief in well-selected patients, are the most commonly performed procedure in pain management. The anatomy of the epidural space provides a framework for understanding risks associated with ESIs, a topic relevant to both patients and physicians in interventional pain, surgery and primary care. Safety considerations of epidural steroids include drug preparation and myriad physiological effects stemming from steroid exposure. Although major complications associated with ESI occur rarely, potentially catastrophic events resulting from infectious, hematologic and neurologic morbidity may lead to permanent injury. The safety profile of ESIs may improve with development and dissemination of sound injection technique, safer compounds manufactured in a sterile manner and deficient of thromboembolic potential and the application of existing technology.

Cervical radicular pain: the role of interlaminar and transforaminal epidural injections

Chronic neck pain and cervical radicular pain are relatively common in the adult population. Treatment for chronic radicular pain recalcitrant to conservative management includes surgical management as well as interventional techniques with epidural injections utilizing either an interlaminar approach or transforaminal approach. Although there have been multiple systematic reviews and randomized clinical trials of cervical interlaminar epidural injections, the literature is sparse in reference to cervical transforaminal epidural injections. Overall, there is good evidence for the effectiveness of cervical interlaminar epidural injections in managing cervical disc herniation and fair evidence in managing central spinal stenosis and postsurgery syndrome. The evidence is poor, however, for cervical transforaminal epidural injections. Complications with cervical interlaminar epidural injections are rare, but more commonly occur with transforaminal epidural injections and can be fatal. Emerging concepts in pain include further randomized trials; proper placebo design; focus on control design (either active control or placebo control); and appropriate methodologic quality assessment and evidence synthesis.

Two-year follow-up results of fluoroscopic cervical epidural injections in chronic axial or discogenic neck pain: a randomized, double-blind, controlled trial

STUDY DESIGN

A randomized, double-blind, active-controlled trial.

OBJECTIVE

To assess the effectiveness of cervical interlaminar epidural injections of local anesthetic with or without steroids for the management of axial or discogenic pain in patients without disc herniation, radiculitis, or facet joint pain.

SUMMARY OF BACKGROUND DATA

Cervical discogenic pain without disc herniation is a common cause of suffering and disability in the adult population. Once conservative management has failed and facet joint pain has been excluded, cervical epidural injections may be considered as a management tool. Despite a paucity of evidence, cervical epidural injections are one of the most commonly performed nonsurgical interventions in the management of chronic axial or disc-related neck pain.

METHODS

One hundred and twenty patients without disc herniation or radiculitis and negative for facet joint pain as determined by means of controlled diagnostic medial branch blocks were randomly assigned to one of the 2 treatment groups. Group I patients received cervical interlaminar epidural injections of local anesthetic (lidocaine 0.5%, 5 mL), whereas Group II patients received 0.5% lidocaine, 4 mL, mixed with 1 mL or 6 mg of nonparticulate betamethasone. The primary outcome measure was ≥ 50% improvement in pain and function. Outcome assessments included numeric rating scale (NRS), Neck Disability Index (NDI), opioid intake, employment, and changes in weight.

RESULTS

Significant pain relief and functional improvement (≥ 50%) was present at the end of 2 years in 73% of patients receiving local anesthetic only and 70% receiving local anesthetic with steroids. In the successful group of patients, however, defined as consistent relief with 2 initial injections of at least 3 weeks, significant improvement was illustrated in 78% in the local anesthetic group and 75% in the local anesthetic with steroid group at the end of 2 years. The results reported at the one-year follow-up were sustained at the 2-year follow-up.

CONCLUSIONS

Cervical interlaminar epidural injections with or without steroids may provide significant improvement in pain and functioning in patients with chronic discogenic or axial pain that is function-limiting and not related to facet joint pain.

Cervical epidural steroid injections for the treatment of cervical spinal (neck) pain

Cervical epidural steroid injections (CESI) are an accepted treatment for neck pain with a radicular component, and may be accomplished by using either transforaminal (CTFESI) or interlaminar (CILESI) approaches. CESIs are routinely performed using real-time fluoroscopic-guidance in conjunction with the injection of water soluble, iodine-based contrast media to enhance visualization of intravascular injections. Digital subtraction angiography (DSA) imaging is an adjuvant to fluoroscopic methods for visualizing blood vessels while performing spinal injections. However, as with any neuraxial procedure, various complications associated with CESIs have been reported. Complications are directly associated with the technical procedures of CESIs. Particulate steroids may have a prolonged duration of action but non-particulate steroids are safer for CESIs. Blunt-beveled needles are less likely than sharp-beveled needles to penetrate blood vessels to cause bleeding complications during CTFESI procedures. Small doses of local anesthetics appear to be safe and assist in identifying intravascular injections previously overlooked by conventional techniques.

Cervical spinal cord injection of epidural corticosteroids: comprehensive longitudinal study including multiparametric magnetic resonance imaging

Despite widespread use, the efficacy of epidural corticosteroid injections (ESI) for osteoarthritis-associated neck or radicular pain remains uncertain, so even rare serious complications enter into discussions about use. However, various factors impede investigation and publication of serious adverse events. To that end, we developed new magnetic resonance imaging (MRI) techniques for spinal cord white matter quantification and used the best available physiological tests to characterize a cervical spinal cord lesion caused by inadvertent intramedullary injection of Depo-Medrol. A 29-year-old woman with mild cervical osteoarthritis had 2 years of headache and neck pain (concussion and whiplash) after 2 minor motor vehicle accidents. During C5-6 ESI, she developed new left-sided motor and sensory symptoms, and MRI demonstrated a new left dorsal spinal cord cavity. Mild left-sided motor and sensory symptoms have persisted for more than 2.5 years, during which time we performed serial neurological examinations, standard electrodiagnostics, somatosensory evoked potentials, and transcranial measurement of corticospinal central motor conduction time (CMCT). We used 3-Tesla MRI with a 32-channel coil developed for high-resolution cervical spinal cord structural imaging, diffusion tensor imaging (DTI), and magnetization transfer (MT). T(2)(∗)-weighted signal and DTI and MT metrics showed delayed spread of the lesion across 4 vertebral levels rostrally, consistent with Wallerian degeneration within the ascending left dorsal columns. However, only CMCT metrics detected objective correlates of her left hemiparesis and bilateral hyperreflexia. DTI and MT metrics may better distinguish between post-traumatic demyelination and axonal degeneration than conventional MRI. These tests should be considered to better characterize similar spinal cord injuries.

An alternative approach to needle placement in cervicothoracic epidural injections

The use of fluoroscopy guidance together with the loss of resistance technique during epidural injections has been advocated lately; moreover, epidural injections in the absence of fluoroscopic guidance have a high rate of inaccurate needle-tip placement during the injections. However, the approach to the lower cervical and upper thoracic epidural space may be challenging due to its obscure lateral fluoroscopic views from overlying normal tissue structures. In this case, we report an alternative oblique C-arm fluoroscopy guided view approach to supplement the standard anterior-posterior and lateral fluoroscopic views to facilitate successful needle placement and precise anatomical localization of the epidural space.

CT fluoroscopy-guided cervical interlaminar steroid injections: safety, technique, and radiation dose parameters

BACKGROUND AND PURPOSE

Cervical epidural steroid injections are approached with trepidation because of concerns over safety, including direct spinal cord injury. CT fluoroscopy is an alternative to conventional fluoroscopy that could potentially help reduce the risk of injury by providing improved localization of the needle tip. We sought to determine rates of technical success and risk of complications in our initial cohort of patients treated with cervical interlaminar ESI performed under CTF guidance.

MATERIALS AND METHODS

In this retrospective case series, we reviewed procedural details and CTF images of 53 consecutive cervical interlaminar ESIs performed on 50 patients over a period of 8 months. Rates of technical success, incidence of complications, procedure times, and factors that influence radiation exposure were examined.

RESULTS

No symptomatic procedural complications were observed. A single case of intrathecal contrast injection was observed, from which the patient was asymptomatic. The remaining injections were all technically successful. Injections were performed at every cervical level, as high as C1-C2. Total procedure times averaged less than 20 minutes. Average CT fluoroscopic time was 24 seconds and median tube current was 70 mA.

CONCLUSIONS

CTF-guided cervical interlaminar ESI can be performed at all levels in the cervical spine with a low rate of procedural complications. Short total procedure times, CT-fluoroscopy times, and reduced tube current make this procedure a practical alternative to cervical ESI performed under conventional fluoroscopy.

The "swimmer's view" as alternative when lateral view is inadequate during interlaminar cervical epidural steroid injections

OBJECTIVE

To present a technique that better visualizes the needle during interlaminar cervical epidural steroid injection (ICESI) in patients where the lateral view is inadequate.

DESIGN

Case report.

SETTING

Private group practice.

SUBJECT

A 57-year-old morbidly obese male presenting for ICESI for left neck and upper limb pain after a motor vehicle accident. Magnetic resonance imaging revealed left C6-7 herniated nucleus pulposis and C4-5 osteophytic disc-ridge complex. Electrodiagnostic evaluation revealed activity consistent with a left C7 radiculopathy.

INTERVENTION

Left C7-T1 ICESI. Needle was obscured in the lateral view by the patient's shoulders. Needle was made visible by positioning the patient for Swimmer's view.

RESULTS

Full resolution of symptoms without associated complications.

CONCLUSIONS

Grave complications have been associated with ICESI necessitating impeccable and systematic technique with substantial knowledge of anatomy. Although injection at lower levels is advocated for safety concerns, the needle during lateral view may be obscured by the shoulders in some patients. The "Swimmer's View" position may be attempted when lateral view is insufficient to visualize needle during ICESI.

Fluoroscopically guided cervical interlaminar epidural injections using the midline approach: an analysis of epidurography contrast patterns

BACKGROUND

The purpose of this study was to evaluate epidurography contrast patterns in fluoroscopically guided cervical interlaminar epidural injections using the midline approach.

METHODS

All epidural injections were performed at the C6-7 level in the prone position. Epidurography was performed using a fixed amount of iotrolan 240 mg I/mL (1, 2, 3 mL).

RESULTS

The rate of ventral epidural spread was 56.7% in Group A (1 mL), 90% in Group B (2 mL), and 93.3% in Group C (3 mL).

CONCLUSIONS

Two milliliters of contrast solution can provide optimal dispersion of contrast in a ventral and longitudinal spread.

Cervical epidural steroid injections in the management of cervical radiculitis: interlaminar versus transforaminal. A review

There has been recent concern regarding the safety of cervical epidural steroid injections. The decision to proceed with treatment requires balancing the risk and benefits. This article is an in depth review of the efficacy, complications, and technique of both interlaminar and transforaminal cervical epidural steroid injections in the management of cervical radiculitis.

Variants in the structure and topography of the superior margin of the epidural space of the human spinal cord

Variants in the structure of the upper margin of the epidural space at sites of transition from the dura mater of the spinal cord to the dura mater of the brain were studied. Stereoepidurographic (88 observations) and corrosion studies (49 observations) identified four levels for the position of the upper margin of the anterior section (intracranially located, lower edge of the occipital bone, bodies of C1 and C2) along with five levels for the posterior section (occipital bone, occipital bone-arch of C1, C1, C1-C2, C2) of the epidural space. Variants on the shape of the upper margin of the anterior (falciform, oval, and dentate in the frontal plane; pointed, flexed spurs, pointed slits, and olive-shaped in the sagittal plane) and posterior (collar-shaped, oval, and bidentate forks with prongs of equal length and forks with prongs of unequal lengths) sections of the epidural space arose as a result of asymmetry in the attachment of the upper sections of the sac of the dura mater of the spinal cord to the walls of the vertebral canal. Weak areas of the upper wall of the epidural space (sites of transition from the dura mater of the spinal cord to the dura mater of the brain, paravasal capsule of the vertebral artery, the area of the first intervertebral foramen) were seen.

Complications of interlaminar cervical epidural steroid injections: a review of the literature

STUDY DESIGN

A comprehensive literature review.

OBJECTIVES

To review and critically evaluate the past literature focusing on incidence and clinical presentation of complications associated with interlaminar cervical epidural steroid injection (ICESI). The overall goal is to guide the direction of future research and improve clinical care by increasing awareness of complications, their presentations, and management.

SUMMARY OF BACKGROUND DATA

Although ICESI is considered a relatively safe procedure, a number of minor and major complications have been reported across the literature. Thus far, reports of complications are limited to retrospective studies, case reports, and data extrapolated from lumbar and thoracic procedures. As a result, the past literature has been of limited value with regard to facilitating both clinical care and future research efforts.

METHODS

Medical databases were searched for studies of ICESI. The bibliographies of these papers were then searched as well. Papers focusing on cervical techniques that did not involve injection into the epidural space were discarded, as were studies of thoracic and lumbar spine injections. Reports of complications associated with ICESI were further subdivided into major and minor categories.

RESULTS

The reported rate of complications associated with ICESI varied between 0 and 16.8%.

CONCLUSION

There are significant limitations in the available literature discussing the complications associated with ICESI, but they strongly suggest that ICESI is a relatively safe procedure. Numerous potential adverse reactions have been associated with ICESI, with the vast majority being minor and transient in nature. However, serious complications may also result and may be technique related. Injectionists should be aware of the clinical presentations, rates, potential consequences, and appropriate techniques to avoid these complications. More studies are needed with specific focus on cervical complication rates, standardization of injection techniques, and differentiation between complications and poor efficacy. In addition, the use of a prospective randomized blinded controlled design would be beneficial.