MR-guided facet joint injection therapy using an open 1.0-T MRI system: an outcome study

Predictors of Outcomes After Lumbar Intra-Articular Facet Joint Injections and Medial Branch Blocks: A Scoping Review

STUDY DESIGN

A scoping review.

OBJECTIVE

We aimed to identify and describe the factors associated with the patient-reported response after lumbar intra-articular facet joint (FJ) injections or medial branch blocks (MBBs).

SUMMARY OF BACKGROUND DATA

FJ osteoarthritis is among the most common causes of chronic low back pain. Management often includes FJ intra-articular injection and MBBs (which may be followed by radiofrequency ablation of the nerves innervating these joints). However, the success of these approaches is variable, prompting interest in identifying patient characteristics (imaging features, clinical signs, and among others) associated with response to these types of facet injections.

MATERIALS AND METHODS

We performed a literature search on factors associated with patient-reported outcomes after lumbar FJ intra-articular injections or MBBs for patients with low back pain published in English or Spanish between 2000 and 2023. We excluded duplicate papers that did not describe factors associated with outcomes or those describing other interventions. We collected data on the association of these factors with patient-reported outcomes.

RESULTS

Thirty-seven studies met the inclusion criteria and were analyzed. These studies evaluated factors, such as age, depression, and single photon emission computed tomography (SPECT), and among variables. Age and imaging findings of facet arthropathy were the most frequently described factors. Imaging findings of FJ arthropathy and positive SPECT were often associated with positive results after intra-articular FJ injections or MBBs. In contrast, younger age and smoking were frequently associated with less favorable clinical outcomes.

CONCLUSION

Numerous factors were considered in the 37 studies included in this review. Imaging findings of facet arthropathy, duration of pain, and positive SPECT were consistently associated with favorable results after facet interventions.

Grading Systems of Lumbar Facet Joint Inflammatory Changes on Magnetic Resonance Imaging: A Scoping Review

STUDY DESIGN

A scoping review.

OBJECTIVE

We aimed to identify and characterize grading systems of the inflammatory features of the lumbar facet joints (FJs) noted on magnetic resonance imaging and summarize their reliability.

SUMMARY OF BACKGROUND DATA

Chronic low back pain is one of the most common causes of disability worldwide and is frequently accompanied by FJ osteoarthritis. Inflammatory changes in the lumbar FJs are commonly noted in imaging studies of patients with FJ osteoarthritis and low back pain. Several grading systems for these inflammatory changes have been developed. However, these grading system's features and reliability have yet to be reviewed.

MATERIALS AND METHODS

We performed a literature search of studies reporting grading systems for FJ inflammatory changes published in English or Spanish between 1985 and 2022. We collected data on reported interreader reliability measures of each grading system. Finally, we compared the features of inflammation described by each system.

RESULTS

Six studies met the inclusion criteria and were used in our analysis. Features commonly graded in these systems are the hyperintensity signal noted within the FJ, bone marrow edema, and the extent of the soft-tissue edema surrounding the FJs. We found that the interreader reliability measures ranged from 0.56 to 0.96.

CONCLUSIONS

Only 6 studies have reported methods for documenting inflammation in the FJs. Studies varied in the precise tissues and phenomena included in the grading systems. However, the systems were generally reliable. Future studies should document the reliability of these methods when independent investigators are not involved in developing the classification schemes. Further work might combine one or more of these measures to establish a standard and reliable grading system for inflammatory changes in the FJs, including signal intensity within the joint, bone marrow edema, and soft-tissue inflammation.

MR-guided lumbar facet radiofrequency denervation for treatment of patients with chronic low back pain in an open 1.0 Tesla MRI system

Background

To evaluate the feasibility, safety and efficacy of magnetic resonance imaging (MRI)-guided lumbar facet joint radiofrequency denervation (FRD) in patients with chronic low back pain.

Methods

The study consisted of two parts. First, a preclinical analysis using an ex vivo animal model was performed to define optimal technical parameters for ablation. Then, 17 patients with chronic lumbar facet joint pain syndrome were prospectively included and underwent MRI-guided FRD in an open 1.0-Tesla MRI. We analyzed technical feasibility and complications as well as clinical outcome in terms of subjective pain assessed on a numerical visual analogue scale (VAS) before and after 1 week/6 months after FRD. Clinical assessment was complemented by measurement of paravertebral muscle volume and fat content before the intervention and at 6-month follow-up.

Results

All interventions were technically successful without major complications. Initial VAS scores (median: 8, IQR: 1, range: 6-9, CI: 7.14-8.04) decreased significantly both after one week (median: 4, IQR: 5, range: 0-7, CI: 1.9-4.69, P=0.003) and after 6 months (median: 1, IQR: 6, range: 0-7, CI: 1.06-4.23, P<0.001). Mean multifidus muscle volume increased significantly in the patient population (from 366.8±130.8 cm³ before to 435.4±146.7 cm³ after FRD, P=0.031).

Conclusions

This proof of principle study shows MRI-guided FRD in an open 1.0-Tesla MRI system to be a potential therapy option for patients with chronic low back pain.

Prognostic factors in low back pain individuals undergoing steroid and anaesthetic intra-articular facet joint infiltration: a protocol for a prospective, longitudinal, cohort study

INTRODUCTION

Lumbar pain of facet origin is a common problem worldwide. For those patients not responding to traditional treatment, one approach may be intra-articular infiltration of corticoid and anaesthetic. However, despite the increasing demand for this procedure, no consensus exists regarding its therapeutic value. The selection of eligible participants may be a determining factor since only those with an inflammatory process will benefit from the use of corticosteroids. This study aims to identify differences in disability, pain and quality of life scores in individuals with and without facet joint inflammation who were diagnosed using MRI.

METHOD AND ANALYSIS

This prospective cohort will include individuals older than 18 years with a clinical diagnosis of facet syndrome who underwent intra-articular infiltration. Changes in scores of pain, disability and quality of life questionnaires at 1, 3, 6 and 12 months of follow-up compared with baseline will be analysed. An MRI examination performed before infiltration will help to distinguish between exposed (with inflammation) and non-exposed (non-inflammation) groups with facet syndrome. The primary outcome will be the disability questionnaire (Roland Morris), and the secondary outcomes will be the score questionnaires for pain (Visual Analogue Scale), quality of life (EuroQol Quality of Life Questionnaire) and disability (Oswestry).

ETHICS AND DISSEMINATION

The Internal Review Board approved this study, which started only after the approval number (5291417.0.0000.0071) was received. All recruited participants will receive a verbal explanation about the purpose of the study, and their decision to participate will be free and voluntary. All participants enrolled in the study will provide a signed informed consent form including confidentiality terms. The results obtained in this study will be presented at national and international conferences and published in peer-reviewed scientific journals to disseminate the knowledge.

TRIALS REGISTRATION NUMBER

NCT03304730; Pre-results.

Deformable image registration for radiation therapy: principle, methods, applications and evaluation

Background: Deformable image registration (DIR) is increasingly used in the field of radiation therapy (RT) to account for anatomical deformations. The aims of this paper are to describe the main applications of DIR in RT and discuss current DIR evaluation methods. Methods: Articles on DIR published from January 2000 to October 2018 were extracted from PubMed and Science Direct. Our search was restricted to articles that report data obtained from humans, were written in English, and address DIR methods for RT. A total of 207 articles were selected from among 2506 identified in the search process. Results: At planning, DIR is used for organ delineation using atlas-based segmentation, deformation-based planning target volume definition, functional planning and magnetic resonance imaging-based dose calculation. In image-guided RT, DIR is used for contour propagation and dose calculation on per-treatment imaging. DIR is also used to determine the accumulated dose from fraction to fraction in external beam RT and brachytherapy, both for dose reporting and adaptive RT. In the case of re-irradiation, DIR can be used to estimate the cumulated dose of the two irradiations. Finally, DIR can be used to predict toxicity in voxel-wise population analysis. However, the evaluation of DIR remains an open issue, especially when dealing with complex cases such as the disappearance of matter. To quantify DIR uncertainties, most evaluation methods are limited to geometry-based metrics. Software companies have now integrated DIR tools into treatment planning systems for clinical use, such as contour propagation and fraction dose accumulation. Conclusions: DIR is increasingly important in RT applications, from planning to toxicity prediction. DIR is routinely used to reduce the workload of contour propagation. However, its use for complex dosimetric applications must be carefully evaluated by combining quantitative and qualitative analyses.

Real-time fusion-imaging in low back pain: a new navigation system for facet joint injections

AIMS AND OBJECTIVES

The aim of the current study is to present our experience in lumbar spine interventional procedures performed with a newly developed multimodal echo-navigator (EcoNav) and to evaluate short-term clinical outcomes of a series of patients affected by facet joint disease (FJD) treated with steroid and anaesthetic injection under fusion-imaging guidance, compared to a cohort of patients that received the same treatment under computed tomography (CT) guidance.

METHODS

Sixty-five consecutive patients (34 females; mean age 68.3 ± 12.8 years) with a clinical diagnosis of non-radicular low back pain lasting for more than 6-weeks and magnetic resonance (MR) or CT confirmed FJD were enrolled for image-guided FJI. Twenty-eight patients underwent FJI with fusion-guided technique, while CT-guided procedures were performed in the other cases. Clinical and procedural data were recorded and compared at a mean follow-up of 6.1 ± 2.0 months.

RESULTS

A significant improvement in clinical parameters was observed for both fusion-guided and CT-guided group. Comparing both groups, no statistically significant difference could be detected neither at baseline conditions nor during the follow-up period. No significant periprocedural complication occurred in both groups. A satisfaction rate of 92.3 and 81.1% was reported for fusion-guided and CT-guided group, respectively.

CONCLUSION

EcoNav fusion-imaging system represents a safe, feasible, effective and reproducible guidance option in FJD infiltration procedures, also avoiding use of ionising radiations.

Tailored interactive sequences for continuous MR-image-guided freehand biopsies of different organs in an open system at 1.0 tesla (T) - Initial experience

OBJECTIVES

To assess the feasibility, image quality, and accuracy of freehand biopsies of liver, bone, muscle, vertebral disc, soft tissue, and other lesions using balanced steady-state free precession (SSFP, balanced fast field echo: bFFE), spoiled and nonspoiled gradient echo (FFE), and turbo spin echo (TSE) sequences for interactive continuous navigation in an open magnetic resonance imaging (MRI) system at 1.0 tesla (T).

METHODS

Twenty-six MR-guided biopsies (five liver, five bone, four muscle, four vertebral disc, one lung, one kidney, one suprarenal gland, and five soft or other tissue) were performed in 23 patients in a 1.0-T open magnetic resonance (MR) scanner (Panorama HFO, Philips Healthcare, Best, the Netherlands). A total of 42 samples were obtained. Depending on lesion size and location, 14-18-gauge MR-compatible biopsy sets with a length of 100 or 200 mm (Somatex Medical, Teltow, Germany), 14-18-gauge MR-compatible semiautomatic biopsy guns with a length of 100 or 150 mm (Invivo, Schwerin, Germany), or 11-gauge MR-compatible bone marrow biopsy needles with a length of 100 mm (Somatex Medical, Teltow, Germany) were employed.

RESULTS

All lesions were visible with continuous interactive imaging. Our initial results indicate that bFFE is particularly suitable for fast-moving organs (pulmonary, paracardial); moving organs are targeted better with T1-weighted (T1W) TSE, T1W FFE (liver) or T2-weighted (T2W) TSE (complicated cysts, adrenal glands), and static organs are successfully approached with proton density (PD) (spine) or T1W TSE (peripheral bones, musculoskeletal system). No adverse events related to the use of MRI were obtained. No complications occurred according to the Society of Interventional Radiology (SIR) clinical practice guidelines.

CONCLUSION

Applying tailored interactive dynamic imaging sequences for continuous navigation to liver, bone, muscle, vertebral disc, soft tissue, and other lesions can improve the feasibility, image quality, and interventional accuracy of freehand MR-guided biopsies and may hence reduce the risk of complications.

In vivo feasibility of real-time MR-US fusion imaging lumbar facet joint injections

OBJECTIVES

Traditionally, facet joint injections (FJI) are performed under fluoroscopic or computed tomography (CT) guidance, mainly due to the deep anatomical location and the presence of bony landmarks. Fusion imaging technology, which couples the ultrasound scan with the corresponding CT or magnetic resonance (MR) image obtained from the diagnostic examination and reformatted in real time according to the ultrasound scanning plane, allows to combine the panoramic view and the elevated anatomical detail of MR or CT with the ease of use of ultrasound without patient exposure to ionizing radiation.

METHODS

Thirty eight patients (24 females; mean age ± SD: 64 ± 9 years) received MR fusion-assisted ultrasound-guided FJI of 1 ml of a mixture of local anaesthetic and corticosteroid using a ultrasound machine (Logiq E9, GE Healthcare) equipped with a GPS-enhanced fusion imaging technology which couples real-time B-mode images with those of the previous recent diagnostic MR examination. Low-dose CT needle positioning confirmation was performed in the first 28 patients. Patients' pain was recorded using a visual analogue scale (VAS), at baseline and at 2, 4 and 8 weeks.

RESULTS

All fusion imaging-guided injections were performed successfully. Out of 112, 96 FJI had optimal intra-articular needle positioning (accuracy: 85.7%). Patients VAS significantly decreases after the procedure with no differences among who received CT needle positioning control and who did not receive it. No major complications were observed.

CONCLUSIONS

Ultrasound needle guidance with MR fusion assistance allows for safe and effective injection of degenerative facet joint disease.

Facet tropism: possible role in the pathology of lumbar disc herniation in adolescents

OBJECTIVE The role of facet tropism (FT) in lumbar disc herniation (LDH) is ambiguous. The present study aimed to investigate the association between FT and LDH in adolescents. METHODS This study included 65 adolescents with LDH with 1- or 2-level LDH, or both. Facet angles were measured with MRI. FT was defined as asymmetry of 10° between the left and right side. The same levels of 30 healthy persons who had no lumbar lesions were used as controls. Statistical analysis was performed using the chi-square test. RESULTS FT was identified in 16 of 39 patients with LDH in L4-5 and in 3 of 30 controls (p = 0.006, OR 6.261, 95% CI 1.619-24.217). It was also identified in 12 of 27 patients with LDH in L5-S1 and in 4 of 30 controls (p = 0.017, OR 5.200, 95% CI 1.420-19.039). One patient had LDH in both L4-5 and L5-S1. CONCLUSIONS FT is associated with LDH in both L4-5 and L5-S1 levels in adolescents.

Irregular Alteration of Facet Orientation in Lumbar Segments: Possible Role in Pathology of Lumbar Disc Herniation in Adolescents

BACKGROUND

The role of the overall structural feature of facet joint in the development of lumbar disc herniation (LDH) is unclear. The present study aimed to investigate the role of irregular alteration of facet orientation (IAFO) in low lumbar segments in the pathology of LDH in adolescents.

METHODS

Sixty-five adolescents with LDH were included in the study. Facet angles were measured in magnetic resonance imaging. The IAFO was defined as the irregular orientation of the included facet joints angle, which was regularly increased from L3 to S1 in the normal group, including small-large-small (SLS) type, large-small-large (LSL) type, and large-small-smaller (LSS) type. Thirty normal adolescents without lumbar lesions were selected into the control group. Statistical analysis was performed using χ(2) test.

RESULTS

IAFO was observed in 20 of 65 subjects in LDH group compared with 3 of 30 in the control group [P = 0.038; OR=4 (1.086, 14.735)]. The SLS type was observed in 14 patients, and the LSL type was found in 6 patients, compared with 2 and 1, respectively, in the control group, no LSS type was found in the two groups. There were 8 subjects with IAFO of SLS style herniated in L5/S1 level compared with 6 subjects in L4/5. There was 1subject with IAFO of LSL style herniated in L5/S1 level compared with 5 subjects in L4/5.

CONCLUSIONS

The findings of this study suggest that the IAFO in the lumbar spine was associated with lumbar disc herniation in adolescents.