Combined vertebroplasty and pedicle screw insertion for vertebral consolidation: feasibility and technical considerations

PURPOSE

To assess the feasibility and technical accuracy of performing pedicular screw placement combined with vertebroplasty in the radiological setting.

METHODS

Patients who underwent combined vertebroplasty and pedicle screw insertion under combined computed tomography and fluoroscopic guidance in 4 interventional radiology centers from 2018 to 2023 were retrospectively assessed. Patient demographics, vertebral lesion type, and procedural data were analyzed. Strict intra-pedicular screw positioning was considered as technical success. Pain score was assessed according to the Visual Analogue Scale before the procedure and in the 1-month follow-up consultation.

RESULTS

Fifty-seven patients (38 men and 19 women) with a mean age of 72.8 (SD = 11.4) years underwent a vertebroplasty associated with pedicular screw insertion for the treatment of traumatic fractures (29 patients) and neoplastic disease (28 patients). Screw placement accuracy assessed by post-procedure CT scan was 95.7% (89/93 inserted screws). A total of 93 pedicle screw placements (36 bi-pedicular and 21 unipedicular) in 32 lumbar, 22 thoracic, and 3 cervical levels were analyzed. Mean reported procedure time was 48.8 (SD = 14.7) min and average injected cement volume was 4.4 (SD = 0.9) mL. A mean VAS score decrease of 5 points was observed at 1-month follow-up (7.7, SD = 1.3 versus 2.7, SD = 1.7), p < .001.

CONCLUSION

Combining a vertebroplasty and pedicle screw insertion is technically viable in the radiological setting, with a high screw positioning accuracy of 95.7%.

Safety and efficacy of cryoablation of Soft-Tissue tumors

OBJECTIVES

To assess the safety and efficacy of percutaneous cryoablation (CA) of soft-tissue tumors (desmoid tumors (DT), vascular malformations (VM), and abdominal wall endometriosis (AWE)).

METHODS

This systematic review of studies published before January 2024 encompassed a detailed analysis of CA techniques and technical aspects for the treatment of soft-tissue tumors. Data concerning CA efficacy, complication rates, and other relevant metrics was extracted and included for analysis.

RESULTS

The analysis included 27 studies totaling 554 CA procedures. For DT (13 studies, 393 sessions), CA showed an average pain reduction of 79 ± 17% (range: 57-100) and a lesion volume decrease of 71.5 ± 9.8% (range: 44-97). VM (4 studies, 58 sessions) had a 100% technical success rate and an average pain reduction of 72 ± 25% (range: 63-85). The average pain reduction for AWE (6 studies, 103 sessions) was 82 ± 13% (range: 62-100). Overall, the complication rate for CA was low, with minor adverse events (AE) in about 20% of patients and major events in less than 5% of patients.

CONCLUSION

Showing substantial efficacy in pain reduction and lesion volume decrease, as well as low incidence of severe AE, CA presents as a highly effective and safe alternative for the treatment of soft-tissue tumors.

ADVANCES IN KNOWLEDGE

CA is effective and safe in treating soft-tissue tumors, particularly DT, VM, and AWE.

Interventional Oncology: 2024 Update

Interventional Oncology (IO) stands at the forefront of transformative cancer care, leveraging advanced imaging technologies and innovative interventions. This narrative review explores recent developments within IO, highlighting its potential impact facilitated by artificial intelligence (AI), personalized medicine and imaging innovations. The integration of AI in IO holds promise for accelerating tumour detection and characterization, guiding treatment strategies and refining predictive models. Imaging modalities, including functional MRI, PET and cone beam CT are reshaping imaging and precision. Navigation, fusion imaging, augmented reality and robotics have the potential to revolutionize procedural guidance and offer unparalleled accuracy. New developments are observed in embolization and ablative therapies. The pivotal role of genomics in treatment planning, targeted therapies and biomarkers for treatment response prediction underscore the personalization of IO. Quality of life assessment, minimizing side effects and long-term survivorship care emphasize patient-centred outcomes after IO treatment. The evolving landscape of IO training programs, simulation technologies and workforce competence ensures the field's adaptability. Despite barriers to adoption, synergy between interventional radiologists' proficiency and technological advancements hold promise in cancer care.

Review of craniofacial pain syndromes involving the greater occipital nerve: relevant anatomy, clinical findings, and interventional management

Craniofacial pain syndromes exhibit a high prevalence in the general population, with a subset of patients developing chronic pain that significantly impacts their quality of life and results in substantial disabilities. Anatomical and functional assessments of the greater occipital nerve (GON) have unveiled its implication in numerous craniofacial pain syndromes, notably through the trigeminal-cervical convergence complex. The pathophysiological involvement of the greater occipital nerve in craniofacial pain syndromes, coupled with its accessibility, designates it as the primary target for various interventional procedures in managing craniofacial pain syndromes. This educational review aims to describe multiple craniofacial pain syndromes, elucidate the role of GON in their pathophysiology, detail the relevant anatomy of the greater occipital nerve (including specific intervention sites), highlight the role of imaging in diagnosing craniofacial pain syndromes, and discuss various interventional procedures such as nerve infiltration, ablation, neuromodulation techniques, and surgeries. Imaging is essential in managing these patients, whether for diagnostic or therapeutic purposes. The utilization of image guidance has demonstrated an enhancement in reproducibility, as well as technical and clinical outcomes of interventional procedures. Studies have shown that interventional management of craniofacial pain is effective in treating occipital neuralgia, cervicogenic headaches, cluster headaches, trigeminal neuralgia, and chronic migraines, with a reported efficacy of 60-90% over a duration of 1-9 months. Repeated infiltrations, neuromodulation, or ablation may prove effective in selected cases. Therefore, reassessment of treatment response and efficacy during follow-up is imperative to guide further management and explore alternative treatment options. Optimal utilization of imaging, interventional techniques, and a multidisciplinary team, including radiologists, will ensure maximum benefit for these patients.

Vertebroplasty versus bracing in acute vertebral compression fractures: A prospective randomized trial

BACKGROUND

The treatment of stable vertebral compression fractures remains controversial.

OBJECTIVE

To compare the efficacy of vertebroplasty and bracing for acute vertebral compression fractures.

METHODS

We conducted a prospective, randomized, non-blinded, single-center study. Adult participants were randomized to undergo vertebroplasty or bracing. Both groups were stratified by age. The primary outcome was functional disability (Roland-Morris disability questionnaire [RMDQ]). Secondary outcomes were pain intensity (Visual Analogue Scale [VAS]), and change in vertebral body height and kyphosis angle. Outcomes were assessed on day 2, and 1, 3 and 6 months after treatment.

RESULTS

Ninety-nine people were included, 51 in the vertebroplasty group and 48 in the brace group. Treatment was performed within 2 weeks of the trauma. On day 2 post-treatment, pain was lower in the vertebroplasty group (mean [SD] 2.3 [1.5] versus 3.4 [2.1], p = 0.004) but the difference was no longer significant at 6 months. Functional disability was significantly lower in the vertebroplasty than brace group at all time-points (RMDQ score 7.5 [5.7] vs 11.4 [5.3], p<0.001 at 1 month). At 6 months, the increase in kyphosis angle was smaller in the vertebroplasty than the brace group (+1.5°versus +4°, p<0.001).

CONCLUSION

In people with acute vertebral compression fractures, the immediate effect of vertebroplasty was greater than that of bracing on pain and function, and for restoring sagittal balance. At 6 months, the superiority of vertebroplasty decreased, except for the maintenance of sagittal balance.

DATABASE REGISTRATION

ClinicalTrials.gov number, NCT01643395.

Tumor or not a tumor: Pitfalls and differential diagnosis in neuro-oncology

The majority of intracranial expansive lesions are tumors. However, a wide range of lesions can mimic neoplastic pathology. Differentiating pseudotumoral lesions from brain tumors is crucial to patient management. This article describes the most common intracranial pseudotumors, with a focus on the imaging features that serve as clues to detect pseudotumors.

Automated Quantification of Brain Lesion Volume From Post-trauma MR Diffusion-Weighted Images

Objectives

Determining the volume of brain lesions after trauma is challenging. Manual delineation is observer-dependent and time-consuming and cannot therefore be used in routine practice. The study aimed to evaluate the feasibility of an automated atlas-based quantification procedure (AQP) based on the detection of abnormal mean diffusivity (MD) values computed from diffusion-weighted MR images.

Methods

The performance of AQP was measured against manual delineation consensus by independent raters in two series of experiments based on: (i) realistic trauma phantoms (n = 5) where low and high MD values were assigned to healthy brain images according to the intensity, form and location of lesion observed in real TBI cases; (ii) severe TBI patients (n = 12 patients) who underwent MR imaging within 10 days after injury.

Results

In realistic TBI phantoms, no statistical differences in Dice similarity coefficient, precision and brain lesion volumes were found between AQP, the rater consensus and the ground truth lesion delineations. Similar findings were obtained when comparing AQP and manual annotations for TBI patients. The intra-class correlation coefficient between AQP and manual delineation was 0.70 in realistic phantoms and 0.92 in TBI patients. The volume of brain lesions detected in TBI patients was 59 ml (19–84 ml) (median; 25–75th centiles).

Conclusions

Our results support the feasibility of using an automated quantification procedure to determine, with similar accuracy to manual delineation, the volume of low and high MD brain lesions after trauma, and thus allow the determination of the type and volume of edematous brain lesions. This approach had comparable performance with manual delineation by a panel of experts. It will be tested in a large cohort of patients enrolled in the multicenter OxyTC trial (NCT02754063).

Assessment of Apparent Diffusion Coefficients and SUVs as Predicators of Histological Differentiation in Anal Squamous Cell Carcinoma

AIM

The study aims to assess minimal apparent diffusion coefficient (ADCmin) and SUVmax as predictors of histological differentiation in patients with anal squamous cell carcinoma (ASCC) and to determine cutoff values for each histopathological tumor grade.

PATIENTS AND METHODS

A retrospective study of 41 ASCC patients (14 males, 27 females; mean age, 65 ± 13 years) staged with FDG PET/CT and MRI (mean scan time interval, 21 ± 11 days). SUVmax and ADCmin values were measured and compared with histopathological tumor grading obtained from biopsy.

RESULTS

The mean size and tumor volume were 3 ± 2 cm and 16.5 ± 27.3 cm3, respectively. The mean ADCmin values for well-, moderately, and poorly differentiated ASCC were 935 ± 179, 896 ± 123, and 637 ± 114, respectively. The mean SUVmax for well-, moderately, and poorly differentiated ASCC were 6.9 ± 1.8, 11.5 ± 4.1, and 13.4 ± 2.6, respectively. The difference in mean ADCmin values between poorly and moderately/well-differentiated tumors was statistically significant, whereas this was not significant between moderately and well-differentiated tumors. Differences in SUVmax values were statistically significant between poorly/moderately and well-differentiated tumors, whereas there was no statistical significance between poorly and moderately differentiated tumors. By combining the 2 modalities using cutoff values of 675 × 10-6 mm2·s-1 for ADCmin and 8.5 for SUVmax, it was possible to differentiate the tumor categories with a sensitivity, specificity, positive predictive value, and negative predictive value, respectively, of 84.6%, 96.4%, 91.7%, and 93.1% for well-differentiated ASCC, 76.5%, 87.5%, 81.3%, and 84% for moderately, and 90.9%, 89.3%, 76.9%, and 96.2% for poorly differentiated ASCC, respectively.

CONCLUSIONS

ADCmin and SUVmax values correlated with the degree of differentiation in ASCC and can be used as predictors of tumor grading and aggressiveness. Combined ADCmin and SUVmax cutoff values can therefore be used for early patient risk stratification and treatment decision making.

Bipolar Radiofrequency Ablation of Painful Spinal Bone Metastases Performed under Local Anesthesia: Feasibility Regarding Patient's Experience and Pain Outcome

Background and objectives: To assess the pain relief of bipolar RFA combined or not with vertebroplasty in patients with painful vertebral metastases and to evaluate the feasibility and tolerance of the RFA procedure performed under local anesthesia. Materials and Methods: 25 patients (18 men, 7 women, mean age: 60.X y.o) with refractory painful vertebral metastasis were consecutively included between 2012 and 2019. A total of 29 radiofrequency ablation (RFA) procedures were performed under CT guidance, local anesthesia and nitrous oxide inhalation, including 16 procedures combined with vertebroplasty for bone consolidation purposes. Pain efficacy was clinically evaluated using the visual analogue scale (VAS) at day 1, 1 month, 3 months, 6 months and 12 months, and the tolerance of the procedure was evaluated. Results: Procedure tolerance was graded as either not painful or tolerable in 97% of cases. Follow-up postprocedure mean VAS score decrease was 74% at day 1: 6.6 (p < 0.001), 79% at 1 month: 6.6 (p < 0.001), 79% at 3 months: 6.5 (p < 0.001), 77% at 6 months, and 79% at 12 months: 6.6 (p < 0.001). Conclusions: Bipolar RFA, with or without combined vertebroplasty, appears to be an effective and reliable technique for the treatment of refractory vertebral metastases in patients in the palliative care setting. It is a feasible procedure under local anesthesia which is well tolerated by patients therefore allowing to broaden the indications of such procedures. Field of study: interventional radiology.

Male Sex Is Associated With Cervical Artery Dissection in Patients With Fibromuscular Dysplasia

Background Cervical artery dissection (CeAD) is a frequent manifestation of fibromuscular dysplasia (FMD). However, risk factors for CeAD are unknown. We investigated factors associated with CeAD in the ARCADIA (Assessment of Renal and Cervical Artery Dysplasia) registry. Methods and Results The ARCADIA registry includes women or men aged ≥18 years, with a diagnosis of renal, cervical, or intracranial artery FMD, who were prospectively recruited at 16 university hospitals in France and Belgium. Diagnosis of acute or past CeAD at inclusion was established on imaging according to standard diagnostic criteria. Associations between potential determinants and CeAD were assessed by logistic regression analyses. Among 469 patients (75 men) with FMD, 65 (13.9%) had CeAD. Patients with CeAD were younger, more likely to be men, have a history of migraine, and less likely to have a history of hypertension than patients without CeAD. In the multivariable analysis, male sex (odds ratio [OR], 2.66; 95% CI, 1.34-5.25), history of migraine (OR, 1.90; 95% CI, 1.06-3.39), age ≥50 years (OR, 0.41; 95% CI, 0.23-0.73), history of hypertension (OR, 0.35; 95% CI, 0.20-0.64), and involvement of ≥3 vascular beds (OR, 2.49; 95% CI, 1.15-5.40) were significantly associated with CeAD. To validate the association between CeAD and sex, we performed a systematic review. We collected additional data on sex from 2 published studies and unpublished data from the US Registry for Fibromuscular Dysplasia and the European/International FMD Registry. In the pooled analysis (289 CeAD, 1933 patients), male sex was significantly associated with CeAD (OR, 2.04; 95% CI, 1.41-2.95; I²=0%). Conclusions In patients with FMD, male sex and multisite involvement are associated with CeAD, in addition to other previously known risk factors. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02884141.

Trans-isthmic pars interarticularis screw fixation under CT and fluoroscopic guidance: technical success and clinical outcome in patients with symptomatic low-grade lumbar isthmic lysis

OBJECTIVES

To assess the technical success of trans-isthmic screw fixation with simultaneous CT and fluoroscopic guidance in patients with symptomatic low-grade isthmic spondylolisthesis.

METHODS

Fifty patients (28 women and 22 men; mean age ± standard deviation: 50 years ± 18.9) presenting with symptomatic low back pain with isthmic spondylolisthesis refractory to medical management were treated by means of trans-isthmic pars interarticularis percutaneous screw fixation. The procedure was performed under local anesthesia with double CT and fluoroscopic guidance. Primary outcome was technical success of the procedure, which was assessed with a post-procedure CT using the same success criteria as surgical screw placement with regard to entry point, trajectory, and screw tip. Secondary outcome was pain decrease assessed by the Visual Analog Scale (VAS).

RESULTS

Ninety-nine procedures were performed in 50 patients and 99 screws were inserted. Postoperative CT assessment showed satisfactory screw placement in 96 cases, reflecting a technical success rate of 96.9%. No complications occurred during or after the procedure. Pain assessment showed a pain decrease of VAS score from a median of 7 (min 5, max 10; MAD 1.4) to 2 (p < 0.0001) (min 0, max 7, MAD 1.7) with a mean follow-up of 39 months.

CONCLUSION

Trans-isthmic screw fixation performed under CT and fluoroscopic guidance presents a high technical success and appears as a safe procedure and effective procedure in patients with symptomatic low-grade isthmic lysis.

KEY POINTS

• Trans-isthmic pars interarticularis percutaneous screw insertion is feasible under double CT and fluoroscopic guidance by a radiologist with a high technical success. • This technique can be performed under local anesthesia only. • In patients with chronic low back pain, isthmic screwing allows long-term pain improvement.

Lumbar medial branch cryoneurolysis under ultrasound guidance: initial report of five cases

AIMS

To assess the feasibility and preliminary results of ultrasound guided medial branch cryoneurolysis in the management of facet joint syndrome.

MATERIAL AND METHODS

Between March 2017 and August 2017, a total of 20 patients underwent medial branch blocks, 12 of which were positive. Five patients chose to participate in the study and 8 medial branch cryoneurolysis were performed. The primary endpoint of the study was the feasibility of the procedure. The secondary endpoint was the efficacy on pain assessed over the following year after the procedure.

RESULTS

Technical feasibility of cryoneurolysis under ultrasound guidance was 100%. Accurate needle positioning at the accurate target in the angle between the posterior aspect of the transverse process and the lateral aspect of the facet joint was achieved in all cases. Needle progression could be depicted with US guidance in all cases. Mean pre-procedural Visual Analogue Scale and Oswestry disability Index scores were 6.8 (range 5-8) and 20.6 (range 12- 31), respectively. Follow up showed a decrease of Visual Analogue Scale score at one month (1.75, range 0-7), and at three months (1.75 range 0-3), Mean self-reported improvement at 6 months was 76% (60- 100%) and 77% at 12 months (50-100%). We report one case of failure at one month. No complications were noted during or after the procedure.

CONCLUSION

Our findings suggest that ultrasound is a valid imaging modality to perform lumbar medial branch cryoneurolysis. Initial results show that cryoneurolysis under ultrasound guidance appears as a safe and effective procedure in patients suffering for facet joint pain.

Facial nerve tractography: A new tool for the detection of perineural spread in parotid cancers

OBJECTIVES

To determine whether facial nerve MR tractography is useful in detecting PeriNeural Spread in parotid cancers.

METHODS

Forty-five participants were enrolled. Thirty patients with surgically managed parotid tumors (15 malignant, 15 benign) were compared with 15 healthy volunteers. All of them had undergone 3T-MRI with diffusion acquisition and post-processing constrained spherical deconvolution-based tractography. Parameters of diffusion-weighted sequences were b-value 1,000 s/mm², 32 directions. Two radiologists performed a blinded visual reading of tractographic maps and graded the facial nerve average pathlength and fractional anisotropy (FA). We also compared diagnostic accuracy of tractography with morphological MRI sequences to detect PeriNeural Spread. Non-parametric methods were used.

RESULTS

Average pathlength was significantly higher in cases with PeriNeural Spread (39.86 mm [Quartile1: 36.27; Quartile3: 51.19]) versus cases without (16.23 mm [12.90; 24.90]), p<0.001. The threshold above which there was a significant association with PeriNeural Spread was set at 27.36 mm (Se: 100%; Sp: 84%; AUC: 0.96, 95% CI 0.904-1). There were no significant differences in FA between groups. Tractography map visual analyses directly displayed PeriNeural Spread in distal neural ramifications with sensitivity of 75%, versus 50% using morphological sequences.

CONCLUSIONS

Tractography could be used to identify facial nerve PeriNeural Spread by parotid cancers.

KEY POINTS

• Tractography could detect facial nerve PeriNeural Spread in parotid cancers. • The average pathlength parameter is increased in case of PeriNeural Spread. • Tractography could map PeriNeural Spread more precisely than conventional imaging.

Dual Site Pudendal Nerve Infiltration: More than Just a Diagnostic Test?

Background: Pudendal neuralgia (PN) is a very painful and often disabling condition in which pudendal nerve blocks play an important role in both the diagnosis and management of PN. Some previous reports have advocated the use of pudendal nerve infiltration (PNI) as a diagnostic test only. Objective: We aim to assess the outcomes of patients with typical refractory PN who underwent dual site computed tomography (CT)-guided pudendal nerve infiltration. Study Design: A bicentric, retrospective cohort analysis. Setting: An academic practice. Methods: Between 2002 and 2016, 385 PNIs were performed in 195 patients in the 2 units. Only patients suffering from typical clinical PN were included, and only the first infiltration in each patient was considered for analysis. Therefore, 95 patients who underwent 155 procedures were assessed. Pain was assessed using a visual analog scale (0–10) and self-reported estimated improvement (SRI), expressed as a percentage. Efficacy of the procedure was assessed at 1, 3, and 6 months after procedure follow-up, and clinical success was defined as a 50% decrease of the VAS score. All procedures were performed under CT guidance and on an outpatient basis. Dual site infiltration was performed in each case at both the ischial spine and intra-Alcock’s canal sites using a mixture of fast- and slow-acting anesthetic (1 mL lidocaine hydrochloride 1% and 2 mL ropivacaine chlorhydrate) along with a half dose of 1.5 mL of cortivazol (3.75 mg). Results: Clinical success at one month post-procedure was present in 63.2% of patients (60/95) with a mean VAS score of 2.07 (P < 0.05) and a mean SRI of 71%. At 3 months follow-up, clinical success was still present in 50.5% of patients (48/95) with a mean VAS score of 2.90/10 (P < 0.05) and a mean SRI of 62.3%. At 6 months follow-up, the efficacy rate decreased to 25.2% with a mean VAS score of 3.2/10 and SRI of 60%. Limitations: The retrospective aspect of the study is a limitation, as well as the lack of a control group. Conclusion: Dual site PNI under CT guidance may offer significant mid-term pain relief to a majority of patients suffering from typical refractory PN. Key words: Pudendal nerve, neuralgia, block, Alcock, CT, guidance

Dual Site Pudendal Nerve Infiltration: More than Just a Diagnostic Test?

BACKGROUND

Pudendal neuralgia (PN) is a very painful and often disabling condition in which pudendal nerve blocks play an important role in both the diagnosis and management of PN. Some previous reports have advocated the use of pudendal nerve infiltration (PNI) as a diagnostic test only.

OBJECTIVE

We aim to assess the outcomes of patients with typical refractory PN who underwent dual site computed tomography (CT)-guided pudendal nerve infiltration.

STUDY DESIGN

A bicentric, retrospective cohort analysis.

SETTING

An academic practice.

METHODS

Between 2002 and 2016, 385 PNIs were performed in 195 patients in the 2 units. Only patients suffering from typical clinical PN were included, and only the first infiltration in each patient was considered for analysis. Therefore, 95 patients who underwent 155 procedures were assessed. Pain was assessed using a visual analog scale (0-10) and self-reported estimated improvement (SRI), expressed as a percentage. Efficacy of the procedure was assessed at 1, 3, and 6 months after procedure follow-up, and clinical success was defined as a 50% decrease of the VAS score. All procedures were performed under CT guidance and on an outpatient basis. Dual site infiltration was performed in each case at both the ischial spine and intra-Alcock's canal sites using a mixture of fast- and slow-acting anesthetic (1 mL lidocaine hydrochloride 1% and 2 mL ropivacaine chlorhydrate) along with a half dose of 1.5 mL of cortivazol (3.75 mg).

RESULTS

Clinical success at one month post-procedure was present in 63.2% of patients (60/95) with a mean VAS score of 2.07 (P < 0.05) and a mean SRI of 71%. At 3 months follow-up, clinical success was still present in 50.5% of patients (48/95) with a mean VAS score of 2.90/10 (P < 0.05) and a mean SRI of 62.3%. At 6 months follow-up, the efficacy rate decreased to 25.2% with a mean VAS score of 3.2/10 and SRI of 60%.

LIMITATIONS

The retrospective aspect of the study is a limitation, as well as the lack of a control group.

CONCLUSION

Dual site PNI under CT guidance may offer significant mid-term pain relief to a majority of patients suffering from typical refractory PN.

KEY WORDS

Pudendal nerve, neuralgia, block, Alcock, CT, guidance.

Erratum to: Greater occipital nerve infiltration under MR guidance: Feasibility study and preliminary results

The original version of this article, published on 12 July 2017, unfortunately contained mistakes. The following corrections have therefore been made in the original.

Greater occipital nerve MR tractography: Feasibility and anatomical considerations

BACKGROUND AND PURPOSE

To assess the feasibility of greater occipital nerve (GON) tractography using a fully automated tractography technique on the whole-neck volume, in comparison with anatomical knowledge.

METHODS

Healthy subjects were consecutively included in this study if they had no history or symptoms of headache or brain disorder. A 3T MRI scanner with a 32 channel head coil was used. The following parameters for Diffusion Weighed (DWI) were used: b value of 1000 s/mm², 32 directions, acquired voxel size: 2 mm isotropic. High-Order tractography with the Constrained Spherical Deconvolution (CSD) model was generated. Track-Weighted Imaging (TWI) maps were generated with MRTrix. Two radiologists performed blind evaluations of the GON pathways on TWI maps.

RESULTS

A total of 20 healthy subjects were included (12 males and eight females, mean age 53.8 years old). In comparison with anatomical atlas, GON complete visualization (from C1-C2 origin to muscular emergence) was possible in 18 out of 20 healthy subjects. In two cases, GON was not visible in the cervical spine foramen.

CONCLUSION

Tractography through TWI is a feasible technique to accurately depict GON. This technique may appear as a promising technique for therapeutic management of patients with occipital neuralgia.

Is brain angio-MRI useful in infective endocarditis management?

In infective endocarditis (IE), brain magnetic resonance imaging (MRI) is helpful to diagnose clinically silent neurological events. We assessed the usefulness of systematic early brain MRI in IE diagnosis and medico-surgical management. Over a period of 1 year, all patients admitted in one of the three hospitals participating in and fulfilling the Duke criteria for definite or possible IE underwent cerebral MRI within 7 days of IE suspicion. Eight panels of experts analyzed the records a posteriori. For each case, one record with and one record without the MRI results were randomly assigned to two panels, which determined the theoretical diagnosis and treatment. Paired comparisons were performed using a symmetry test. Thirty-seven brain MRIs were performed within a median of 5 days after inclusion. MRI was pathological in 26 patients (70 %), showing 62 % microischemia and 58 % microbleeds. The expert advice did not differ significantly between the two evaluations (with or without the MRI results). The therapeutic strategies determined diverged in five cases (13.5 %). Diagnosis differed in two cases (5.4 %), with an upgrading of diagnosis from possible to definite IE using MRI results. Early brain MRI did not significantly affect the IE diagnosis and medico-surgical treatment plan. These results suggest that systematic use of early brain MRI is irrelevant in IE. Further studies are necessary to define whether MRI is mandatory in IE management within a multidisciplinary approach, with particular attention paid to better timing and the subset of patients in whom this imaging examination could be beneficial.

Ultrasound-Guided Intermediate Site Greater Occipital Nerve Infiltration: A Technical Feasibility Study

BACKGROUND

Two studies recently reported that computed tomography (CT) guided infiltration of the greater occipital nerve at its intermediate site allows a high efficacy rate with long-lasting pain relief following procedure in occipital neuralgia and in various craniofacial pain syndromes.

OBJECTIVE

The purpose of our study was to evaluate the technical feasibility and safety of ultrasound-guided intermediate site greater occipital nerve infiltration.

STUDY DESIGN

Retrospective study.

SETTING

This study was conducted at the imaging department of a 1,409 bed university hospital.

METHODS

Local institutional review board approval was obtained and written consent was waived. In this retrospective study, 12 patients suffering from refractory occipital neuralgia or craniofacial pain syndromes were included between April and October 2014. They underwent a total of 21 ultrasound-guided infiltrations. Infiltration of the greater occipital nerve was performed at the intermediate site of the greater occipital nerve, at its first bend between obliqus capitis inferior and semispinalis capitis muscles with local anestetics and cortivazol. Technical success was defined as satisfactory diffusion of added iodinated contrast media in the fatty space between these muscles depicted on control CT scan. We also reported first data of immediate block test efficacy and initial clinical efficacy at 7 days, one month, and 3 months, defined by a decrease of at least 50% of visual analog scale (VAS) scores.

RESULTS

Technical success rate was 95.24%. Patients suffered from right unilateral occipital neuralgia in 3 cases, left unilateral occipital neuralgia in 2 cases, bilateral occipital neuralgia in 2 cases, migraine in one case, cervicogenic headache in one case, tension-type headache in 2 cases, and cluster headache in one case. Block test efficacy was found in 93.3% (14/15) cases. Clinical efficacy was found in 80% of cases at 7 days, in 66.7% of cases at one month and in 60% of cases at 3 months. No major complications were noted.

LIMITATIONS

Some of the limitations of our study include that it represents a single institution. The low number of infiltrations included in this study, for this guidance procedure, is another bias.

CONCLUSIONS

This ultrasound-guided infiltration technique appears to be feasible, safe, non-ionizing, and fast when targeting the greater occipital nerve in its intermediate portion. This imaging guidance modality should be used in routine clinical practice.

KEY WORDS

Greater occipital nerve, infiltration, ultrasound guidance, corticosteroids, occipital neuralgia, craniofacial pain syndrome.

Value of brain MRI in infective endocarditis: a narrative literature review

The nervous system is frequently involved in patients with infective endocarditis (IE). A systematic review of the literature was realized in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). This study sought to systematically evaluate the published evidence of the contribution of brain magnetic resonance imaging (MRI) in IE. The aim was to identify studies presenting the incidence and type of MRI brain lesions in IE. Fifteen relevant studies were isolated using the Medline, Embase, and Cochrane databases. Most of them were observational studies with a small number of patients. MRI studies demonstrated a wide variety and high frequency of cerebral lesions, around 80 % of which were mostly clinically occult. This review shows MRI’s superiority compared to brain computed tomography (CT) for the diagnosis of neurologic complications. Recent developments of sensitive MRI sequences can detect microinfarction and cerebral microhemorrhages. However, the clinical significance of these microhemorrhages, also called cerebral microbleeds (CMBs), remains uncertain. Because some MRI neurological lesions are a distinctive IE feature, they can have a broader involvement in diagnosis and therapeutic decisions. Even if cerebral MRI offers new perspectives for better IE management, there is not enough scientific proof to recommend it in current guidelines. The literature remains incomplete regarding the impact of MRI on concerted decision-making. The long-term prognosis of CMBs has not been evaluated to date and requires further studies. Today, brain MRI can be used on a case-by-case basis based on a clinician’s appraisal.

The brain signature of paracetamol in healthy volunteers: a double-blind randomized trial

BACKGROUND

Paracetamol's (APAP) mechanism of action suggests the implication of supraspinal structures but no neuroimaging study has been performed in humans.

METHODS AND RESULTS

This randomized, double-blind, crossover, placebo-controlled trial in 17 healthy volunteers (NCT01562704) aimed to evaluate how APAP modulates pain-evoked functional magnetic resonance imaging signals. We used behavioral measures and functional magnetic resonance imaging to investigate the response to experimental thermal stimuli with APAP or placebo administration. Region-of-interest analysis revealed that activity in response to noxious stimulation diminished with APAP compared to placebo in prefrontal cortices, insula, thalami, anterior cingulate cortex, and periaqueductal gray matter.

CONCLUSION

These findings suggest an inhibitory effect of APAP on spinothalamic tracts leading to a decreased activation of higher structures, and a top-down influence on descending inhibition. Further binding and connectivity studies are needed to evaluate how APAP modulates pain, especially in the context of repeated administration to patients with pain.

Fibromuscular dysplasia: what the radiologist should know: a pictorial review

Abstract

Fibromuscular dysplasia (FMD) is an idiopathic, segmentary, non-inflammatory and non-atherosclerotic disease that can affect all layers of both small- and medium-calibre arteries. The prevalence of FMD is estimated between 4 and 6 % in the renal arteries and between 0.3 and 3 % in the cervico-encephalic arteries. FMD most frequently affects the renal, carotid and vertebral arteries, but it can theoretically affect any artery. Radiologists play an important role in the diagnosis of FMD, and good knowledge of FMD’s signs will certainly help reduce the delay between the first symptoms and diagnosis. The common string-of-beads aspect is well known, but less common presentations also have to be considered. These less common imaging findings include vascular loops, fusiform vascular ectasia, arterial dissection, aneurysm and subarachnoid haemorrhage. These radiologic presentations should be known by radiologists in order to diagnose possible FMD, particularly when present in young females or when associated with personal or familial hypertension, to reduce the delay between the onset of the first symptom and the final diagnosis. The patients have to be referred to specialised FMD centres for dedicated management.

Teaching Points

• Fibromuscular dysplasia is not a rare disease.

• Radiologists should recognise less common presentations to orient specific management.

• Vascular loops, fusiform vascular ectasia and a “string-of-beads” aspect are typical presentations.

• Arterial dissection, aneurysm and subarachnoid haemorrhage are less typical radiologic presentations.

Microwave thermal ablation of spinal metastatic bone tumors

PURPOSE

To assess feasibility, safety, and efficacy of microwave ablation of spinal metastatic bone tumors.

MATERIALS AND METHODS

Retrospective study of 17 patients with 20 spinal metastatic tumors treated with microwave ablation under computed tomographic guidance between March 2011 and August 2013 was performed. Ablations were performed under local anesthesia and nitrous oxide ventilation. Lesions were lumbar (n = 10), sacral (n = 7), and thoracic (n = 3) in location. Primary neoplastic sites were lung (n = 9), prostate (n = 4), kidney (n = 6), and uterus (n = 1). Adjunct cementoplasty was performed in nine cases, and a temperature-monitoring device was used in four cases. Procedure effectiveness was evaluated by visual analog scale (VAS) during a 6-month follow-up. Patient medical records were reviewed, and demographic and clinical data, tumor characteristics, and information on pain were assessed.

RESULTS

Mean ablation time was 4.4 minutes ± 2.7 (range, 1-8 min), with an average of 3.8 cycles per ablation at 60 W (range, 30-70 W). The preprocedure mean VAS score was 7.4 ± 1.2 (range, 6-9). Pain relief was achieved in all but one patient. Follow-up VAS scores were as follows: day 0, 1.3 ± 1.8 (P < .001); day 7, 1.6 ± 1.7 (P < .001); month 1, 1.9 ± 1.6 (P < .001); month 3, 2.2 ± 1.5 (P < .001); and month 6, 2.3 ± 1.4 (P < .01). No complications were noted.

CONCLUSIONS

Microwave ablation appears to be feasible, safe, and an effective treatment of painful refractory spinal metastases and may be considered as a potential alternative percutaneous technique in the management of spinal metastases.

Treatment of painful extraspinal bone metastases with percutaneous bipolar radiofrequency under local anesthesia: feasibility and efficacy in twenty-eight cases

PURPOSE

To retrospectively assess the feasibility and efficacy of bipolar radiofrequency ablation (RFA) of extraspinal osseous neoplasms performed under local anesthesia.

METHODS AND MATERIALS

Twenty-eight patients (21 males, 7 females; mean age, 61.2 years) underwent RFA under local anesthesia between 2005 and 2012. All included patients suffered from painful osseous metastases refractory to previous medication; all presented with end-stage neoplasms. RFA was performed under computed tomography (CT) guidance with bipolar radiofrequency probes. All procedures were performed under local anesthesia (lidocaine-ropivacaine) and nitrous oxide ventilation. Intravenous injection of paracetamol was performed throughout the procedure with or without intravenous injection of nalbuphin. Tolerance of procedure was recorded. Pain efficacy was evaluated on visual anologue scale (VAS) scores at day 7, 1 month, and at 6 months after the procedure.

RESULTS

Technical success rate was 100%. The procedure was considered not painful in 4 cases and tolerable in 20 cases. Average procedural time was 23.1 minutes. Mean VAS score prior to RFA was 8.1/10. Significant decrease of pain was noted at day 7 (3.3/10, p<0.001, n=27), 1 month (3.8/10, p<0.001, n=27), and 6 months (4.5/10, p<0.001, n=13). No complications were noted.

CONCLUSION

Bipolar RFA of osseous metastases is a safe and effective treatment for refractory bone metastases. Its feasibility under local anesthesia should broaden the indications.

Biomechanical properties of the calcaneal tendon in vivo assessed by transient shear wave elastography

OBJECTIVE

The purpose of this study is to assess the elastic and anisotropic properties of normal calcaneal tendon in vivo by transient shear wave elastography (SWE).

MATERIALS AND METHODS

This study was approved by our institutional ethics committee. Eighty healthy subjects over 18 years of age were prospectively included. Data on the patients' height, weight, sporting activities, and take-off foot were assessed. The thickness, width, and cross-sectional area of the calcaneal tendons were measured. The shear wave propagation velocity (Vmean) was measured by three radiologists on axial and sagittal SWE images at four different degrees of ankle flexion, enabling to calculate elasticity modulus (Emean), and relative anisotropy coefficient (A) values.

RESULTS

In complete plantar flexion, Vmean was 6.8 ± 1.4 m.s(-1) and 5.1 ± 0.8 m.s(-1), respectively, on the sagittal and axial SWE image, resulting in an elastographic anisotropy A of 0.24 ± 0.16. The best interobserver correlation coefficient of Emean and Vmean was 0.43 and 0.46, respectively, in the sagittal SWE for complete plantar flexion. Vmean and Emean significantly increase when the tendon is stretched by ankle dorsiflexion. The maximal values in sagittal SWE were Vmean = 16.1 ± 0.7 m.s(-1), Emean = 779.5 ± 57.1kPa and A = 0.63 ± 0.07.

CONCLUSIONS

SWE allows the elastic properties of the calcaneal tendon to be evaluated quantitatively in vivo, but interobserver reproducibility is questionable. It confirms the tendinous elastographic anisotropy and stiffness augmentation of stretched tendon.

Preoperative imaging in the planning of deep inferior epigastric artery perforator flap surgery

Breast reconstruction with adipocutaneous free flap from the abdominal wall combines the benefits of abdominoplasty to those of a prosthesis-free breast reconstruction. The deep inferior epigastric artery perforator (DIEP) flap is supplied by intramuscular perforators from the deep inferior epigastric artery (DIEA). It consists of the dissection of perforating branches of the DIEA within the rectus abdominis muscle, thus sparing both muscle and fascia. Preoperative imaging in the planning of DIEP flap surgery has been shown to facilitate faster and safer surgery. This review article aims to discuss advantages and drawbacks of current imaging modalities for mapping the course of perforating vessels in the planning of DIEP flap surgery, and to present state-of-the-art imaging techniques.

CT-guided stellate ganglion blockade vs. radiofrequency neurolysis in the management of refractory type I complex regional pain syndrome of the upper limb

OBJECTIVE

To describe and evaluate the feasibility and efficacy of CT-guided radiofrequency neurolysis (RFN) vs. local blockade of the stellate ganglion in the management of chronic refractory type I complex regional pain syndrome (CRPS) of the upper limb.

METHODS

Sixty-seven patients were included in this retrospective study between 2000 and 2011. All suffered from chronic upper limb type I CRPS refractory to conventional pain therapies. Thirty-three patients underwent stellate ganglion blockade and 34 benefited from radiofrequency neurolysis of the stellate ganglion. CT guidance was used in both groups. The procedure was considered effective when pain relief was ≥50 %, lasting for at least 2 years.

RESULTS

Thirty-nine women (58.2 %) and 28 men (41.8 %) with a mean age of 49.5 years were included in the study. Univariate analysis performed on the blockade and RFN groups showed a significantly (P < 0.0001) higher success rate in the RFN group (67.6 %, 23/34) compared with the blockade group (21.2 %, 7/33) with an odds ratio of 7.76.

CONCLUSION

CT-guided radiofrequency neurolysis of the stellate ganglion is a safe and successful treatment of chronic refractory type I CRPS of the upper limb. It appears to be more effective than stellate ganglion blockade.

KEY POINTS

• Complex regional pain syndrome is painful, disabling and often refractory to treatment. • Sixty-seven percent of patients had lasting pain relief (2 years) after radiofrequency neurolysis. • Retrospective study showed a significantly higher success rate for radiofrequency neurolysis. • CT guidance is mandatory for a successful and safe procedure.