Use of gadolinium chelate to confirm epidural needle placement in patients with an iodinated contrast reaction

Lead migration and postdural puncture headache following spinal cord stimulator placement in patient with cough: a case report

Introduction and importance

Spinal cord stimulator (SCS) implantation has become a well-validated treatment for refractory chronic back pain. While generally safe, complications such as lead migration and postdural puncture headache (PDPH) can arise. Recognizing these hardware and biologic complications is crucial to improving outcomes and guiding management strategies.

Case presentation

A middle-aged male with chronic nocturnal cough underwent successful percutaneous SCS trial placement under fluoroscopic guidance. Adequate pain coverage was confirmed, and he was discharged home. The following day, he returned with a positional headache, nausea, and imaging-confirmed lead migration. PDPH was suspected. At the time of presentation, a chest X-ray revealed possible lead migration, and the patient had also reported a chronic dry cough that had worsened the evening of the procedure. Management included removal of the leads and an epidural blood patch, leading to complete symptom resolution.

Clinical discussion

Nocturnal coughing is hypothesized to have caused mechanical stress on the SCS leads, resulting in caudal migration. Lead migration is one of the most common SCS complications, with rates of 2.1-27%. Additionally, PDPH, though rare (~0.81% per lead placed), often requires an epidural blood patch for effective resolution. In this case, the displaced leads may have exacerbated an underlying dural tear, highlighting a novel interplay between hardware and biological complications.

Conclusion

This is the first documented case at our academic center of concurrent lead migration and PDPH following SCS placement. Our findings suggest that chronic coughing may represent an unrecognized risk factor for lead migration and PDPH. Providers should address unresolved coughing prior to SCS implantation and consider improved anchoring techniques to minimize risks.

Are gadolinium-based contrast media safe alternatives to iodinated contrast agents for the safe performance of spinal injection procedures?

This FactFinder presents a brief summary of the evidence regarding the safety of gadolinium-based contrast media (GBCM) for spinal interventions.

The contralateral oblique fluoroscopic view is associated with a lower incidence of postdural puncture headache in patients undergoing percutaneous spinal cord stimulation

BACKGROUND

Spinal cord stimulation (SCS) is a minimally invasive therapy that is increasingly used to treat refractory neuropathic pain. Although this technique has a low incidence of serious long-term adverse sequelae, the risk of complications such as inadvertent dural puncture remains.

OBJECTIVES

The goal of this article was to determine the impact of the contralateral oblique (CLO) fluoroscopic view incidence of postdural puncture headache (PDPH) during spinal cord stimulator implantation as compared to lateral fluoroscopic view.

METHODS

This was a single academic institution retrospective analysis of electronic medical records spanning an approximate 20-year time period. Operative and postoperative notes were reviewed for details on dural puncture, including technique and spinal level of access, the development of a PDPH, and subsequent management.

RESULTS

Over nearly two decades, a total of 1637 leads inserted resulted in 5 PDPH that were refractory to conservative measures but responded to epidural blood patch without long-term complications. The incidence of PDPH per lead insertion utilizing loss of resistance and lateral fluoroscopic guidance was 0.8% (4/489). However, adoption of CLO guidance was associated with a lower rate of PDPH at 0.08% (1/1148), p < 0.02.

CONCLUSIONS

The incorporation of the CLO view to guide epidural needle placement can decrease the odds of a PDPH during percutaneous SCS procedures. This study further provides real-world data supporting the potential enhanced accuracy of epidural needle placement in order to avoid unintentional puncture or trauma to deeper spinal anatomic structures.

Dural Puncture During Spinal Cord Stimulator Lead Insertion: Analysis of Practice Patterns

BACKGROUND

Spinal cord stimulation (SCS) is an important modality for intractable pain not amenable to less conservative measures. During percutaneous SCS lead insertion, a critical step is safe access to the epidural space, which can be complicated by a dural puncture.

OBJECTIVES

In this review, we present and analyze the practices patterns in the event of a dural puncture during a SCS trial or implantation.

METHODS

We conducted a survey of the practice patterns regarding spinal cord stimulation therapy. The survey was administered to members of the Spine Intervention Society and American Society of Regional Anesthesia specifically inquiring decision making in case of inadvertent dural puncture during spinal cord stimulator lead insertion.

RESULTS

A maximum of 193 responded to a question regarding dural punctures while performing a SCS trial and 180 responded to a question regarding dural punctures while performing a SCS implantation. If performing a SCS trial and a dural puncture occurs, a majority of physicians chose to continue the procedure at a different level (56.99%), followed by abandoning the procedure (27.98%), continuing at the same level (10.36%), or choosing another option (4.66%). Similarly, if performing a permanent implantation and a dural puncture occurs, most physicians chose to continue the procedure at a different level (61.67%), followed by abandoning the procedure (21.67%), continuing at the same level (10.56%), or choosing another option (6.11%).

CONCLUSIONS

Whereas the goals of the procedure would support abandoning the trial but continuing with the permanent in case of inadvertent dural puncture, we found that decision choices were minimally influenced by whether the dural puncture occurred during the trial or the permanent implant. The majority chose to continue with the procedure at a different level while close to a quarter chose to abandon the procedure. This article sets a time stamp in practice patterns from March 20, 2020 to June 26, 2020. These results are based on contemporary SCS practices as demonstrated by this cohort, rendering the options of abandoning or continuing after dural puncture as reasonable methods. Though more data is needed to provide a consensus, providers can now see how others manage dural punctures during SCS procedures.

An Operator's Experience of the Loss-of-Resistance Technique in Epidural Injections: An Observational Study

Objective

A successful interlaminar epidural injection relies on correct epidural space needle placement. Most interlaminar epidural steroid injection (ESI) procedures are performed with a blind technique known as loss-of-resistance (LOR) without an imaging guide. This study aims to evaluate the success rate of the LOR technique in interlaminar epidural steroid injection under fluoroscopic control.

Materials and Methods

Patients who underwent interlaminar ESI owing to a history of at least 3 months of chronic low back and leg pain not responding to medications and physical therapies were included in an observational trial. Participants' age was between 27 and 88 years, and they had an American Society of Anesthesiologists physical status of I-III. The patients were placed in a prone position, and a Tuohy needle was introduced at the level of the L5-S1 interlaminar foramen using fluoroscopic image with an anteroposterior view. A lateral view was obtained when the LOR was felt. The procedures that achieved epidural spread by contrast agent in the first attempt were deemed successful. Those that did not and those that had false positive LOR were regarded as unsuccessful.

Results

Interlaminar ESİ was administered to 150 patients. The procedure's success and failure rates were 76% (114 patients) and 24% (36 patients), respectively. A total of 58.3% (21 patients) of patients who underwent an unsuccessful procedure had a false LOR, whereas 41.6% (15 patients) of the same group exhibited other causes. Sex, age, and body mass index (BMI) showed no statistical significance in terms of procedural success. There were statistically significant differences in the distance between the skin and the epidural space according to the body mass index groups.

Conclusion

The LOR technique identified the epidural space in most epidural procedures. However, in some cases, LOR was shown to be inadequate. Therefore, we suggest that the LOR technique must be supported by imaging such as fluoroscopy during epidural injections.

Spinal Injections for Pain Management

Image-guided spinal injection is commonly performed in symptomatic patients to decrease pain severity, confirm the pain generator, and delay or avoid surgery. This article focuses on the radiologist as spine interventionist and addresses the following four topics relevant to the radiologist who performs corticosteroid injections for pain management: (a) the rationale behind corticosteroid injection, (b) the interaction with patients, (c) the role of imaging in procedural selection and planning, and (d) the pearls and pitfalls of fluoroscopically guided injections. Factors that contribute to the success of a pain management service include communication skills and risk mitigation. A critical factor is the correlation of clinical symptoms with magnetic resonance (MR) imaging findings. Radiologists can leverage their training in MR image interpretation to distinguish active pain generators in the spine from incidental abnormalities. Knowledge of fluoroscopic anatomy and patterns of contrast material flow guide the planning and execution of safe and effective needle placement. ^© RSNA, 2016 Online supplemental material is available for this article.

Relative Conspicuity of Gadolinium-Based Contrast Agents in Interventional Pain Procedures

Objective

To assess the relative radiographic conspicuity of gadolinium-based contrast agents (GBCAs) that may be used in spinal injection procedures when iodine-based contrast agents are contraindicated.

Methods

Eight GBCAs and three iodinated agents of varying iodine concentrations were radiographed under conditions representative of lumbar spinal injections at four kilovoltage peak (kVp) values. Radiographic contrast of each agent was measured as the percent pixel value difference with respect to background.

Results

Gadobutrol (Gadovist, 1 mM/mL) had the highest radiographic contrast among the gadolinium agents tested. Measured radiographic contrast correlated with the molar concentration of gadolinium. Gadobutrol radiographic contrast lies between the contrast of iohexol concentrations of 240 and 140 mgI/mL. All agents have decreasing contrast as kVp increases, but GBCAs decrease less than iodine-based agents.

Conclusions

Gadobutrol is the GBCA with the greatest conspicuity for use in spinal injection procedures. It also has the highest molar concentration of gadolinium, and potential neural toxicity from intrathecal delivery must be considered.

What is the evidence? The issue of verifying correct needle position during epidural anaesthesia in dogs

OBJECTIVES

To review the methods for verifying the needle position while performing epidural anaesthesia in dogs, and to discuss the advantages, disadvantages, usefulness and reliability of each technique in the experimental and clinical research setting.

DATABASES USED

PubMed, Scopus, Google Scholar and the Basel University Library online catalogues; the latter, which was provided by the University of Berne, were used as databases. The results were filtered manually based on the titles and abstracts in order to narrow the field.

CONCLUSIONS

Besides some drawbacks, including the potential side effects of contrast medium injection, which may limit its routine use in clinical patients, epidurography should still be regarded as one of the most reliable techniques to verify needle position in dogs. Ultrasonography, electrical nerve stimulation, loss of resistance and the hanging drop technique are regarded as less invasive than epidurography and, for this reason, their use may be more applicable to clinical patients. However, these methods have been described in only a few published reports, all of which involved a limited number of dogs. Finally, the detection of epidural pressure waves has been investigated more extensively in dogs, and the findings of these studies suggest that this technique may be used to verify epidural needle placement for experimental and clinical research, on condition that all the negative subjects are excluded from the study.

The Incidence and Management of Postdural Puncture Headache in Patients Undergoing Percutaneous Lead Placement for Spinal Cord Stimulation

BACKGROUND

Spinal cord stimulation (SCS) is rapidly expanding therapy for the treatment of refractory neuropathic pain. Although technical issues such as battery life and lead migration have been well studied and improved, little is known about the incidence and management of inadvertent dural puncture and consequent headache.

OBJECTIVES

The goals of this article were to determine the incidence of postdural puncture headache (PDPH) per lead insertion at the various regions of the spine and to detail the use of conservative management and epidural blood patch (EBP). Long-term outcomes are reviewed to validate treatment modalities employed.

METHODS

Retrospective analysis of electronic medical records identified by patient implant registry and current procedural terminology data for nearly a 13-year time interval. Operative and postoperative notes were reviewed for details on dural puncture, access technique and spinal level, the development of a PDPH, and the treatment employed with particularly emphasis on the use of (EBP).

RESULTS

A total of 745 leads inserted resulted in 6 PDPH that were refractory to conservative measures but responded to EBP without long-term complications. The overall incidence of PDPH per lead insertion was 0.81%. Leads placed anterograde in the thoracolumbar (T11-L3) and Cervicothoracic (C7-T5) regions resulted in an incidence of PDPH per lead of 0.63% and 1.1%, respectively, while 5.9% occurred with lumbar retrograde approach, and none with caudal.

CONCLUSIONS

Dural puncture during SCS device placement and can result in a PDPH that is severe and refractory to conservative modes of therapy. Even in the presence of hardware, EBP performed with meticulous aseptic technique was found to be safe and efficacious.

Contralateral Oblique View Is Superior to the Lateral View for Lumbar Epidural Access

OBJECTIVE

The purpose of this study was to perform a comparative analysis of the contralateral oblique (CLO) view and the lateral view for lumbar interlaminar epidural access.

DESIGN

After the epidural space was accessed, fluoroscopic images at eight different angles (antero-posterior view, multiple CLO, and lateral view) were prospectively obtained. Visualization and location of needle tip relative to bony landmarks were analyzed. The epidural location of the needle was subsequently confirmed by contrast injection and analysis in multiple views.

RESULTS

Visualization of the needle tip and the relevant radiologic landmarks was superior in the CLO view. The needle tip location in the epidural space was most consistent at a CLO angle of 45°.

CONCLUSION

This study shows that the CLO view for lumbar interlaminar epidural access offers clear advantages over the lateral view on many clinically important grounds: the needle tip visualization is better, the important radiological landmarks are better visualized, and the needle tip when placed in the epidural space presents a more precise relationship to these landmarks. All of these differences were highly significant. Thus, when using this view, the needle may be directly placed in very close vicinity to the epidural space and true loss of resistance expected soon thereafter. In addition, this view provides the ability to plot the cranio-caudad needle trajectory. The combination of these factors is likely to improve the ease and efficiency of epidural access. The crisp visualization of the final moments of epidural access could also translate to improved safety and accuracy. In light of this, it is suggested that a CLO view at 45° be considered the preferred view for gauging needle depth during interlaminar lumbar epidural access.

MR epidurography: distribution of injectate at caudal epidural injection

OBJECTIVE

To (a) evaluate the feasibility of MR epidurography (MRE) and (b) assess the distribution of injectate using two different volumes at caudal epidural steroid injection.

MATERIALS AND METHODS

Twenty patients who were referred with symptomatic low back pain for caudal epidural steroid injection were assigned to have either 10 ml (9/20) or 20 ml (11/20) of injectate administered. Gadolinium was included in the injection. The patients proceeded to MRI where sagittal and coronal T1-weighted fat-saturated sequences were acquired and reviewed in the mid-sagittal and right and left parasagittal views at the level of the exit foramina.

RESULTS

Gadolinium was observed at or above the L3/4 disc level in all 11 patients who received 20 ml (100 %), compared with only five of nine patients who received 10 ml (56 %). Injectate was seen to the L4 nerve root level in all 11 patients who received 20 ml (100 %) but only four out of nine patients who received 10 ml (44 %), not even reaching the L5 nerve root level in four further of these nine patients (44 %). Overall, there was a trend to visualize gadolinium at higher levels of the epidural space with higher volumes injected.

CONCLUSIONS

Firstly, MR epidurography is a safe technique that allows excellent visualization of the distribution of gadolinium in the epidural space following injection via the caudal hiatus. Secondly, a volume of 10 ml is unlikely to treat L5/S1 disease in almost half of patients at caudal epidural steroid injection and at least 20 ml of injectate is likely required for any medication to reach the desired level.

Magnetic resonance neurography-guided nerve blocks for the diagnosis and treatment of chronic pelvic pain syndrome

Magnetic resonance (MR) neurography - guided nerve blocks and injections describe a techniques for selective percutaneous drug delivery, in which limited MR neurography and interventional MR imaging are used jointly to map and target specific pelvic nerves or muscles, navigate needles to the target, visualize the injected drug and detect spread to confounding structures. The procedures described, specifically include nerve blocks of the obturator nerve, lateral femoral cutaneous nerve, pudendal nerve, posterior femoral cutaneous nerve, sciatic nerve, ganglion impar, sacral spinal nerve, and injection into the piriformis muscle.

High-resolution magnetic resonance-guided posterior femoral cutaneous nerve blocks

OBJECTIVE

To assess the feasibility, technical success, and effectiveness of high-resolution magnetic resonance (MR)-guided posterior femoral cutaneous nerve (PFCN) blocks.

MATERIALS AND METHODS

A retrospective analysis of 12 posterior femoral cutaneous nerve blocks in 8 patients [6 (75%) female, 2 (25%) male; mean age, 47 years; range, 42-84 years] with chronic perineal pain suggesting PFCN neuropathy was performed. Procedures were performed with a clinical wide-bore 1.5-T MR imaging system. High-resolution MR imaging was utilized for visualization and targeting of the PFCN. Commercially available, MR-compatible 20-G needles were used for drug delivery. Variables assessed were technical success (defined as injectant surrounding the targeted PFCN on post-intervention MR images) effectiveness, (defined as post-interventional regional anesthesia of the target area innervation downstream from the posterior femoral cutaneous nerve block), rate of complications, and length of procedure time.

RESULTS

MR-guided PFCN injections were technically successful in 12/12 cases (100%) with uniform perineural distribution of the injectant. All blocks were effective and resulted in post-interventional regional anesthesia of the expected areas (12/12, 100%). No complications occurred during the procedure or during follow-up. The average total procedure time was 45 min (30-70) min.

CONCLUSIONS

Our initial results demonstrate that this technique of selective MR-guided PFCN blocks is feasible and suggest high technical success and effectiveness. Larger studies are needed to confirm our initial results.

Magnetic resonance imaging-guided spine injections

Magnetic resonance (MR)-guided spine injections describe techniques for selective spine injection procedures, in which MR imaging is used to visualize spinal targets and needle placement, monitor the injected drugs, and detect spread to potentially confounding nearby structures. The introduction of clinical high-field wide-bore MR imaging systems has increased the practicability and availability of MR-guided spine injections. The use of 1.5-T field strength, modern coils, and parallel imaging technology increases the MR signal, which can be utilized for faster temporal image acquisition, higher image resolution, better image contrast, or combinations thereof. Magnetic resonance imaging guidance provides excellent osseous and soft-tissue detail of spinal structures and is well suited to avoid radiation exposure. In this article, we discuss the technical background of interventional MR imaging, review the literature, and illustrate interventional MR imaging techniques of commonly performed spinal injection procedures, including sacroiliac joint injections, lumbar facet joint injections, selective spinal nerve root infiltration, and percutaneous drug delivery to the lumbar sympathetic nerves.

Spinal injection procedures: a review of concepts, controversies, and complications

The field of spinal injection procedures is growing at a tremendous rate. Many disciplines are involved, including radiology, anesthesiology, orthopedics, physiatry and rehabilitation medicine, as well as other specialties. However, there remains tremendous variability in the assessment of patients receiving these therapies, methods for evaluation of outcome, and in the understanding of where these procedures belong in the triaging of those who require surgery. In this article, we attempt to highlight the biologic concepts on which these therapies are based, controversies that have arisen with their increasing use, and a description of complications that have been reported.