Percutaneous injection of radiopaque gelified ethanol for the treatment of lumbar and cervical intervertebral disk herniations: experience and clinical outcome in 80 patients

Abstract

Background and purpose: Chemonucleolysis represents a minimally invasive percutaneous technique characterized by an intradiskal injection of materials under fluoroscopic or CT guidance. Recently, a substance based on radiopaque gelified ethanol has been introduced. The purpose of this study was to describe the indications, procedure, safety, and efficacy of radiopaque gelified ethanol in the percutaneous treatment of cervical and lumbar disk herniations.

Materials and methods: Between September 2010 and August 2013, 80 patients (32 women and 48 men; age range, 18-75 years) were treated for 107 lumbar disk herniations (L2-L3, n = 1; L3-L4, n = 15; L4-L5, n = 53; and L5-S1, n = 38) and 9 cervical disk herniations (C4-C5, n = 2; C5-C6, n = 2; C6-C7, n = 3; and C7-D1, n = 2) by percutaneous intradiskal injection of radiopaque gelified ethanol under fluoroscopic guidance. Thirty-six patients underwent a simultaneous treatment of 2 disk herniations. Patient symptoms were resistant to conservative therapy, with little or no pain relief after 4-6 weeks of physical therapy and drugs. All patients were evaluated by the Visual Analog Scale and the Oswestry Disability Index.

Results: Sixty-two of 73 (85%) patients with lumbar disk herniations and 6/7 (83%) patients with cervical disk herniations obtained significant symptom improvement, with a Visual Analog Scale reduction of at least 4 points and an Oswestry Disability Index reduction of at least 40%. Leakage of radiopaque gelified ethanol in the surrounding tissues occurred in 19 patients, however without any clinical side effects.

Conclusions: In our experience, percutaneous intradiskal injection of radiopaque gelified ethanol is safe and effective in reducing the period of recovery from disabling symptoms.

© 2015 by American Journal of Neuroradiology.

Figures

Fig 1.

Progressive intervertebral disk filling of RGE. Real-time fluoroscopic images showing RGE inside the nucleus pulposus and in the herniated disk (arrows). Tungsten allows proper visualization of the material, including monitoring of possible leakage.

Fig 2.

VAS scores recorded before and after percutaneous intradiskal injection of RGE. The left panel displays the boxplot of the data. Before treatment, the VAS scores were mostly concentrated on the upper values of the scale (median = 7; 25th percentile = 7; 75th percentile = 8); therefore, this distribution was negatively skewed (skewness = −0.29). The distribution of the VAS scores in the posttreatment survey (median = 3; 25th percentile = 2; 75th percentile = 4) became positively skewed (skewness = 0.91). No outliers were identified. The reduction of 4 points in the median of the VAS scores between pre- and posttreatment was significant for the nonparametric Wilcoxon matched-pairs signed rank test (W = −3076; P < .0001). The barplots in the right panel show the means and SDs of the data. The decrease of the means of the VAS scores from 7.16 ± 0.79 to 3.61 ± 1.72 was significant under the paired t test with 78 df (t = 17.61; P < .0001).

Fig 3.

ODI scores recorded before and after percutaneous intradiskal injection of RGE. The index is expressed in percentage points and ranges from 0% to 100%. The lower limit corresponds to the absence of disability; the upper limit, to the maximum degree of disability (patients are bed-bound). The left panel displays the boxplot of the data. Before treatment, the distribution of ODI scores (median = 48%; 25th percentile = 42%; 75th percentile = 58%) was slightly negatively skewed (skewness = −0.05), and it became positively skewed (skewness = 1.21) in the posttreatment survey (median = 14%; 25th percentile = 10%; 75th percentile = 18%). No outliers were identified. Between the pre- and posttreatment periods, the medians of the VAS scores dropped by 34 percentage points. This decline was significant for the nonparametric Wilcoxon matched-pairs signed rank test (W = −3076; P < .0001). The barplots in the right panel show the means and SDs of the data. The decrease of the mean of the ODI scores from 47.85 ± 9.05 to 17.47 ± 14.41 was significant with the paired t test with 78 df (t = 17.71, P < .0001).

Fig 4.

Treatment of a very large extruded LDH in a 58-year-old woman with left sciatica (VAS = 8). A, In a preoperative MR imaging study, sagittal and axial T2 sequences show a large uncontained and partially migrated disk herniation at L5–S1 (median left posterolateral), with considerable root involvement (white arrow). B, CT control shows the optimal distribution of RGE in a disk herniation without leakage (black arrow). The patient did not have significant symptoms (VAS = 3). C, MR imaging study obtained 6 months later shows complete dehydration and retraction of disk herniation. The patient was completely asymptomatic (VAS = 0).

Fig 5.

Treatment of a CDH in a 45-year-old woman with left brachialgia (VAS = 7). A, T2-weighted sagittal and T2*-weighted axial MR images show a C4–C5 left posterolateral disk herniation. Note also other asymptomatic disk bulging at the C3–C4, C5–C6, and C6–C7 levels. Anteroposterior radiograph (B) and CT axial image (C) obtained at the end of the procedure confirm the proper distribution of RGE in the treated disk, especially in the herniated portion (arrows).