Cervical foraminal steroid injections under CT guidance: retrospective study of in situ contrast aspects in a serial of 248 cases

Venous congestion as a central mechanism of radiculopathies

Compression of roots/nerves can disrupt some of their functions, but does not necessarily cause pain. This is illustrated by the frequency of nearly asymptomatic spinal stenosis or disc herniations. In fact, pain of radiculopathies (and nerve entrapments) may mostly be the consequence of intraneural oedema induced by microscopical venous stasis around roots/spinal ganglia (or nerves) not or poorly shown by imaging. This narrative review first lists arguments for a role of congestion of vasa-nervorum in the pathophysiology of radiculopathies, including those induced by disc herniation and spinal stenosis, but also other sources of overpressures in spinal venous plexuses (pregnancy, vena cava atresia and thrombosis, portal hypertension, epidural varices, arterio-venous fistula, vertebral hemangioma or hemangioblastoma). It also details sources of venous congestion around nerves outside the spine, from pelvis (May-Thurner syndrome, Nut-cracker syndrome) to buttocks (superior and inferior gluteal veins), and even thighs and legs. A better recognition of a preeminent role of venous congestion in radiculopathies, plexopathies, and nerve entrapments, should have major consequences: (i) discard the dogma that compression is mandatory to induce root/nerve suffering, since root/nerve adherences in two locations can impair blood flow in vasa-nervorum through root/nerve stretching; (ii) implementation of sensitive techniques to visualise impingement of blood flow around or within roots and nerves; (iii) better prevention of roots/nerves adherence, or arachnoiditis induced by extravascular fibrin deposition secondary to venous stasis.; (iv) optimizing treatments dampening clot formation and/or extravascular fibrin leakage in the intradural/peridural spaces, or around roots/nerves, like guided injection of tissue plasminogen activator.

Spinal Cord Injury by Direct Damage During CT-Guided C7 Transforaminal Epidural Steroid Injection

Cervical transforaminal epidural steroid injection (TFESI) under the guidance of computed tomography (CT) can offer great anatomical resolution and precise needle placement in the axial plane. However, some complications, including blood pressure surge, allergic reactions, vasovagal syncope, and cerebral infarct, have been reported after CT-guided cervical TFESI. We report the first case of iatrogenic spinal cord injury during a CT-guided cervical TFESI. A 67-year-old woman, upon receiving TFESI on Lt. C7, experienced an electrical shock-like sensation throughout the body. The patient complained of weakness in the left upper and lower extremities (manual muscle testing grade: 2-4) and neuropathic pain (numeric rating scale: 9) in the left upper and lower extremities. Cervical magnetic resonance imaging (MRI) performed 9 days after TFESI showed a high T2 signal at the left side of the spinal cord from levels C5 to C7, and an electrophysiological study performed 14 days after TFESI revealed corresponding findings with cervical MRI. Three months after finishing treatment with a high dose of intravenous methylprednisolone, the patient's motor weakness improved, but it did not recover fully.

Safety of CT-guided cervical nerve root corticosteroid injections

INTRODUCTION

Computed tomography-guided cervical nerve root corticosteroid injections are a commonly performed procedure for cervical radiculopathy. There have been major complications such as spinal cord infarction and posterior circulation stroke reported mostly with X-ray fluoroscopic-guided methods, however, there is relatively little data on the safety of newer CT-guided methods. The purpose of this study was to identify any major complications and evaluate the rate of minor complications from CT-guided cervical nerve root corticosteroid injections performed in a tertiary public hospital.

METHODS

Four hundred and three CT-guided cervical nerve root injection procedures were identified over a period from July 2015 to January 2018 using the radiology information system (RIS) and data collected about the technique and any immediate complications. Patient follow-up and delayed complications were then reviewed, either via outpatient clinic records or telephone consultation.

RESULTS

Two hundred and eighty-six procedures were performed by radiology registrars or fellows, and 117 by radiologists, most commonly via an anterolateral approach and injecting 4 mg (in 1 mL) of dexamethasone. Follow-up data were obtained for all 403 procedures and identified 16 minor complications, but no major neurovascular complications.

CONCLUSION

The overall recorded rate of minor complications with CT-guided nerve root injection was 4.0% with no major neurovascular complications, suggesting that CT-guided transforaminal cervical corticosteroid injection is a safe procedure.

Comparison of three CT-guided epidural steroid injection approaches in 104 patients with cervical radicular pain: transforaminal anterolateral, posterolateral, and transfacet indirect

INTRODUCTION

The treatment of persistent cervical radicular pain (CRP) by CT-guided epidural steroid injections (CTESI) by a transforaminal anterolateral (TFA) approach is associated with rare but serious complications. Two recently described transforaminal posterolateral (TFP) and transfacet indirect (TFT) approaches may be safer options, but have not been extensively evaluated. We compared the efficacy of three CTESI approaches (TFA, TFP, and TFT) in the treatment of persistent CRP (>6 weeks).

METHODS

Patients were prospectively assessed for pain using the visual analog scale (VAS) and for functional disability by the Neck Disability Index (NDI) before treatment, then 6 weeks and 6 months after CTESI.

RESULTS

A total of 104 patients were included (n = 30 TFA, n = 36 TFP, and n = 38 TFT approaches). Each group was found to have a statistically significant improvement at 6 weeks (median VAS values: 7 (2-9) at D0 and 2 (3-6) at 6 weeks p < 0.01; median NDI values: 38 (24-50) at D0 and 29 (18-42) at 6 weeks (p < 0.01)), and at 6 months (median VAS values: 7 (2-9) at D0 and 4 (2-6) at 6 months (p < 0.01); median NDI values: 38 (24-50) at D0 and 28 (13-40) at 6 months (p < 0.01)). No significant difference was observed in the decrease in VAS and NDI scores among the three approaches at 6 weeks (p = 0.635 and p = 0.54 for VAS and NDI respectively) or 6 months (p = 0.704 and p = 0.315 for VAS and NDI respectively). No major complications were noted.

CONCLUSION

The results of CTESI using the TFP or TFT approach are similar to those for TFA in the treatment of persistent CRP and could be a safer option.

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.