Redundant nerve roots on magnetic resonance imaging can predict ongoing denervation in patients with lumbar spinal stenosis.

INTRODUCTION/AIMS: Redundant nerve roots (RNRs) are abnormally elongated and tortuous nerve roots that develop secondary to degenerative spinal stenosis. RNRs have been associated with poorer clinical outcomes after decompression surgery; however, studies on their clinical characteristics are limited. This study aimed to investigate the association between RNRs and denervation potentials, that is, abnormal spontaneous activity (ASA), on electromyography. METHODS: We retrospectively reviewed data of patients who underwent an electrodiagnostic study of the lower extremities between January 2020 and March 2023. Of these, patients with lumbar central spinal stenosis, as seen on magnetic resonance imaging, were included. We analyzed clinical and imaging data, including presence of ASA, and compared them according to the presence of RNRs. Multivariable logistic regression analysis was employed to identify factors associated with development of ASA. RESULTS: Among the 2003 patients screened, 193 were included in the study. RNRs were associated with advanced age (p < .001), longer symptom duration (p = .009), smaller cross-sectional area of the dural sac at the stenotic level (p < .001), and higher frequency of ASA (p < .001). Higher probability of ASA was correlated with greater RNR severity (p < .001). In the multivariable logistic regression analysis, ASA occurrence was associated with smaller cross-sectional area, multiple stenotic sites, and severe-grade RNRs. DISCUSSION: The presence of RNRs, particularly severe-grade RNRs, was identified as a significant risk factor for the development of ASA on electromyography. This finding may aid physicians in estimating the prognosis of patients with central spinal stenosis.

Evaluation of Fluoroscopically Guided Transforaminal Selective Nerve Root Sleeve Injections for Lumbar Spinal Stenosis With Radiculopathy Utilizing Patient Reported Outcome Measurement Information System as an Outcome Measure.

OBJECTIVE: To evaluate the therapeutic effect of transforaminal selective nerve root sleeve injections (TFSNRIs) in a specific subset of patients with clinical symptoms and presentation consistent with spinal stenosis. DESIGN: Retrospective review. SETTING: Tertiary academic spine center. PARTICIPANTS: A total of 176 patients with radicular leg pain with or without low back pain as well as ≥3 clinical features of spinal stenosis and corroborative radiographic features of spinal stenosis on lumbar spine magnetic resonance imaging without confounding spinal pathology (N=176). INTERVENTIONS: Fluoroscopically guided transforaminal selective nerve root sleeve injections. MAIN OUTCOME MEASURES: Patient Reported Outcome Measurement Information System (PROMIS) Physical Function (PF) v1.2/v2.0, Pain Interference (PI) v1.1, and PROMIS (D) v1.0 were collected at baseline and post-procedure short term (<3-months) and long-term (6-12 month) follow-up. Statistical analysis comparing baseline and postprocedural PROMIS scores was performed. Differences were compared with previously established minimal clinically important differences in the spine population. RESULTS: For patients with spinal stenosis treated with TFSNRI, no statistically significant improvement was observed short- and long-term follow-up in PROMIS PF (P=.97, .77) and PROMIS Depression (P=.86, .85) scores. At short-term follow-up, PROMIS PI scores did significantly improve (P=.01) but the average difference of pre- and post-procedure scores did not reach clinical significance. No significant difference in PROMIS PI was noted at long-term follow-up (.75). CONCLUSIONS: Although a statistically significant difference was observed for improvement in pain, in this retrospective study, TFSNRI did not provide clinically significant improvement in patients' function, pain, or depression for lumbar spinal stenosis at short- and long-term follow-up.

Neurosarcoidosis involving cervical nerve root with unusual MRI findings: a case report and systematic literature review.

BACKGROUND: Neurosarcoidosis is rare, and among its manifestations, nerve root involvement has been reported in only a few cases. Therefore, magnetic resonance imaging (MRI) findings of neurosarcoidosis, particularly those involving nerve roots, are scarce in the literature. METHODS: We presented the case of neurosarcoidosis involving cervical nerve roots and cranial nerves, alongside a systematic literature review. RESULTS: A 28-year-old female suddenly developed right facial numbness as well as left upper extremity and left hand pain. Initial brain and spine MRI showed a bulging mass of T2 iso-to-high signal intensity in the left Meckel's cave/trigeminal nerve, as well as diffuse enlargement of the right C6 and C7 nerve roots. Follow-up MRI at 2 months revealed a reduction in the size of the initial lesion and the appearance of new similar lesions on the contralateral side (right Meckel's cave, left C3-C8 nerve roots). In particular, the lesions involving the nerve roots demonstrated central enlargement along the nerve roots, without involvement of the adjacent spinal cord. All these lesions exhibited enhancement, leading to the differentiation between sarcoidosis and lymphoma. Sarcoidosis was subsequently confirmed through biopsy of a hilar lymph node. CONCLUSIONS: This report presents a distinctive MRI feature of neurosarcoidosis involving spinal nerve roots, representing the first of its kind, and describes the evolution of MRI findings throughout the clinical course.

Validation of the Root Analysis Score for C5 Viability in Patients With Pan-Brachial Plexus Injury.

PURPOSE: Pan-brachial plexus injury patients present a reconstructive challenge. The root analysis score, developed from parsimonious multivariable modeling of 311 pan-brachial plexus injury patients, determines the probability of having a viable C5 nerve based on four categories: positive C5 Tinel test, intact C5 nerve on computed tomography myelogram, lack of hemidiaphragmatic elevation, and absence of midcervical paraspinal fibrillations. METHODS: Root analysis scores were calculated for a separate cohort of patients with pan-brachial plexus injuries. Scores were validated by the presence or absence of a graftable C5 root, based on supraclavicular exploration and intraoperative electrophysiologic testing. Receiver operating characteristic curve, accuracy, and concordance statistic of the scores were calculated. Patients were divided into three root analysis score cohorts: less than 50 (low), 50-75 (average), and 75-100 points (high) based on dividing the score into quartiles and combining the lowest two. The probability, sensitivity, and specificity of each cohort having an available C5 nerve were based on the intraoperative assessment. RESULTS: Eighty patients (mean age, 33.1 years; 15 women and 65 men) were included. Thirty-one patients (39%) had a viable C5 nerve. The root analysis calculator had an overall accuracy of 82.5%, a receiver operating characteristic of 0.87, and a concordance statistic of 0.87, demonstrating high overall predictive value; 6.5% of patients with a score of less than 50 (94% sensitivity and 43% specificity), 16.1% of patients with a score of 50-75 (94% sensitivity and 67% specificity), and 77.4% of patients with a score of 75-100 (77% sensitivity and 90% specificity) had a graftable C5 nerve. CONCLUSIONS: The root analysis score demonstrated high accuracy and predictive power for a viable C5 nerve. In patients with a score of less than 50, the necessity of supraclavicular root exploration should balance patient factors, presentation timing, and concomitant injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnosis II.

Primary neurolymphomatosis diagnosed by spinal nerve root biopsy.

Primary neurolymphomatosis is the direct infiltration of lymphomatous neoplastic cells into nerve roots and/or peripheral nerves. A 67-year-old man had a 24-month history of progressive and severe left lower limb neuropathic pain, ipsilateral ankle dorsiflexion weakness and gait disturbance. Gadolinium-enhanced MRI showed thickening and enhancement of the cauda equina, L5, S1 and S2 nerve roots. 18Fluorodeoxyglucose positron emission tomography showed concordant hypermetabolism. L5 nerve root biopsy confirmed diffuse large B-cell lymphoma. One cycle of rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) chemotherapy resulted in remission, but this was not sustained. Primary neurolymphomatosis is rare and diagnostically challenging, and often the diagnosis is delayed. While biopsy is the gold standard for diagnosis, neuroimaging helps to characterise lesions and to determine the feasibility of biopsy.

Further case of enlarged spinal nerve roots in KRAS-related Noonan syndrome.

Noonan syndrome (NS) belongs to RASopathies, a family of disorders caused by unregulated signaling through the RAS-MAPK pathway. Herein, we report on an individual with molecularly confirmed diagnosis of NS showing asymptomatic enlarged spinal nerve roots, which are distinctive features of neurofibromatosis type 1. To date, a total of 16 patients with neurogenic tumors resembling neurofibromas/schwannomas and a molecularly confirmed diagnosis of a non-NF1 RASopathy have been reported, adding this further feature shared among RASopathies.

Anterior lumbosacral polyradiculoneuropathy following intrathecal methotrexate administration: a case report and literature update.

INTRODUCTION: We describe a case of intrathecal methotrexate toxicity and perform a literature review of existing cases. CASE PRESENTATION: A 23-year-old man who received diagnosis of acute lymphoblastic leukemia and started chemotherapy according to the LAL1913 protocol underwent CNS prophylaxis with intrathecal methotrexate. About 1 month after, he developed a flaccid paraparesis. CSF analysis showed albumin/cytological dissociation. Spinal MRI showed thickening of the ventral roots of the cauda equina with contrast enhancement. Nerve conduction studies showed severe lower limb motor axonal neuropathy. Needle examination showed acute denervation involving L3-S1 roots. Methotrexate was stopped, and the patient was treated with intravenous immunoglobulins, followed by high-dose intravenous methylprednisolone, with a gradual improvement. Three months later, the spine MRI was normal. Electrophysiological and imaging findings were indicative of pure motor L3-S1 polyradiculopathy. DISCUSSION: Literature review of existing cases confirm the relatively selective involvement of lumbosacral ventral roots in intrathecal methotrexate toxicity. Pathophysiologic mechanisms suggest either a direct toxicity with localized folate deficiency or an immune-mediated mechanism, the latter consistent, in our patient, with the albumin/cytological dissociation and response to immunomodulatory treatments. Pure motor polyradiculopathy of the lower limbs is rare but predictable complication of intrathecal methotrexate, which can benefit from early withdrawal and immunomodulatory treatments.

Applicative value of T2 mapping in evaluating lumbosacral nerve root injury induced by lumbosacral disc herniation.

BACKGROUND: To alleviate the damage caused by nerve root entrapment mediated by lumbosacral disc herniation (LDH), an imaging method that allows quantitative evaluation of the lumbosacral nerve injury is necessary. PURPOSE: To investigate the diagnostic value of magnetic resonance (MR) T2 mapping in nerve root injury caused by LDH. MATERIAL AND METHODS: A total of 70 patients with unilateral sciatic nerve pain and 35 healthy volunteers were divided into three groups: LDH with nerve root entrapment; LDH without nerve root entrapment; and 35 healthy volunteers. All participants underwent 3.0-T MR with T1-weighted (T1W) imaging, T2-weighted (T2W) imaging, and T2-mapping images. T2 was measured and observed with the left and right nerve roots of the L4-S1 segments in healthy volunteers; the differences between the three groups were compared. T2 and the relaxation rate of nerve root injury were analyzed. RESULTS: T2 showed significant differences among the three groups (F = 89.494; P = 0.000), receiver operating characteristic curve revealed that the T2 relaxation threshold was 79 ms, the area under curve (AUC) area was 0.86, sensitivity was 0.77, and specificity was 0.74; the T2 relaxation rate was 1.06, the AUC area was 0.88, sensitivity was 0.74, and specificity was 0.85. CONCLUSION: T2 mapping could quantitatively evaluate the nerve root injury with lumbar disc degeneration. Hence, it can be used for the clinical evaluation of nerve root entrapment caused by LDH.

Additional benefit of ultrasonography to evaluate nerve root condition of degenerative cervical spine disease.

STUDY DESIGN: A cross-sectional explanatory study. OBJECTIVES: To clarify the nerve root condition and the association between nerve root cross-sectional area (CA) on ultrasonography (US) and other examinations such as MRI or compound muscle action potentials (CMAPs) in degenerative cervical spine diseases. SETTING: A university hospital in Japan. METHODS: Fifty-one patients diagnosed with proximal cervical spondylotic amyotrophy (CSA) (13 patients), cervical radiculopathy of C5 or C6 nerve root (CR) (26 patients), or cervical spondylotic myelopathy (CSM) (12 patients), and twenty-nine healthy volunteers were included in this study. Neurological findings, US findings and CMAPs of deltoid and biceps muscles of all participants were evaluated. In addition, CSA, CR, and CSM patients underwent MRI. RESULTS: A significant correlation was not observed between CA and CMAP amplitude or foraminal diameter on MRI (P > 0.05). In the US examination, the C6 CA of the affected side of the CR group was significantly larger than that of both the normal side and the other groups (P < 0.001). The C5 CA of the affected side of the CSA group clearly showed a bimodal distribution: enlarged and small CA groups. In the CMAP findings, CSA cases respectively showed the lower amplitude of deltoid and bicep CMAPs on both the normal and the affected side (P ≦ 0.01). CSM and healthy volunteers were nearly identical in CA and CMAPs. CONCLUSION: Utilizing US in addition to NCS and MRI can contribute towards an evaluation of the nerve root condition of degenerative cervical spine disease. SPONSORSHIP: no sponsorship.

Intraneural hemangioma of spinal nerve roots: a Case Report and literature review.

Intraneural hemangiomas are rare benign neoplasms. We report the case of a 53­year­old female with a hemangioma in a spinal nerve root. The patient presented with muscular atropy of the right arm wihout obvious predisposing factors one year ago. MRI demonstrated a heterogeneously enhanced lesion adjacent to the right C4/5 intervertebral foramen. The lesion was considered to be a schwannoma preoperatively. Histologically, the lesion was abundant with intervening malformed vascular mass lined by simple squamous epithelial cells, and CD31 was positively stained at these epithelial cells by immunohistochemistry. The patient underwent microsurgical resection and recovered without complications.

Cervical nerve root variant: report of two cases under the cervical endoscopy and review of clinical literature.

BACKGROUND: We know of five cases of cervical nerve root variants that have been reported, all of which were found during posterior cervical surgery. We reported two cases of cervical nerve root variants. One had two anomalous branches of the C7 root, is the other had a C5, C6 nerve root communication branch. CASE DESCRIPTION: A 62-year-old female presented with neck and right upper extremity pain, accompanied by hypaesthesia in her right forearm for 4 months. Preoperative X-ray film, magnetic resonance imaging (MRI) and computed tomography (CT) scan demonstrated C6-7 uncovertebral joint hyperplasia and foraminal stenosis. She underwent posterior cervical endoscopic foraminoplasty. The right C7 nerve root was observed to have two anomalous branches originated from a proximal trunk. After the surgery, the symptoms resolved. A 54-year-old female presented with radiating pain and numbness in her right arm and hand for 4 months. Preoperative MRI showed a C5/6 intervertebral disc herniation. She had hypaesthesia in radial side of her right arm and 1st-3rd fingers. Posterior cervical endoscopic foraminalplasty was performed for the patient. After decompression of the bony wall of the posterior nerve root canal, a 2-mm thick communicating nerve was observed emerging from the dura with the C6 nerve root and exiting to the caudal level. After the surgery, the symptoms resolved immediately. CONCLUSIONS: Cervical nerve root variant may be more apparent on edoscopic approaches to the cervical foraminae than at open surgery.

A comparative study of the anatomy and MRI images of the lumbar foraminal ligaments at the L1-L5 levels.

PURPOSE: The purpose of this study was to evaluate the ability of MRI images to reveal foraminal ligaments at levels L1-L5 by comparing the results with those of anatomical studies. METHODS: Eighty lumbar foramina were studied. First, the best MRI scanning parameters were selected, and the transverse and sagittal axes of each lumbar foramina were scanned to identify and record the ligament-like structures in each lumbar foramen. Then, the cadaveric specimens were anatomically studied, and all ligament structures in the lumbar foramina were retained. The number, morphology and distribution of ligaments under anatomical and MRI scanning were observed. Histological staining of the dissected ligament structures was performed to confirm that they were ligamentous tissues. Finally, the accuracy of ligament recognition in MRI images was statistically analyzed. RESULTS: A total of 233 foraminal ligaments were identified in 80 lumbar intervertebral foramina through cadaveric anatomy. The radiating ligaments (176, 75.5%) were found to be attached from the nerve root to the surrounding osseous structures, while the transforaminal ligaments (57, 24.5%) traversed the intervertebral foramina without any connection to the nerve roots. A total of 42 transforaminal ligament signals and 100 radiating ligament signals were detected in the MRI images of the 80 intervertebral foramina. CONCLUSION: The MRI can identify the lumbar foraminal ligament, and the recognition rate of the transforaminal ligament is higher than that of the radiating ligament. This study provides a new method for the clinical diagnosis of the relationship between the lumbar foraminal ligament and radicular pain.

Spinal Nerve Roots Abnormalities on MRI in a Child with SURF1 Mitochondrial Disease.

Variants in SURF1, encoding an assembly factor of mitochondrial respiratory chain complex IV, cause Leigh syndrome (LS) and Charcot-Marie-Tooth type 4K in children and young adolescents. Magnetic resonance imaging (MRI) appearance of enlarged nerve roots with postcontrastographic enhancement is a distinctive feature of hypertrophic neuropathy caused by onion-bulb formation and it has rarely been described in mitochondrial diseases (MDs). Spinal nerve roots abnormalities on MRI are novel findings in LS associated with variants in SURF1. Here we report detailed neuroradiological and neurophysiologic findings in a child with LS and demyelinating neuropathy SURF1-related. Our case underlines the potential contributive role of spinal neuroimaging together with neurophysiological examination to identify the full spectrum of patterns in MDs. It remains to elucidate if these observations remain peculiar of SURF1 variants or potentially detectable in other MDs with peripheral nervous system involvement.

Ultrasonographic evaluation reveals thinning of cervical nerve roots and peripheral nerves in spinal and bulbar muscular atrophy.

BACKGROUND: Ultrasonography (US) is a noninvasive and patient-friendly tool for the evaluation of peripheral nerves. In motor neuron diseases, amyotrophic lateral sclerosis (ALS) has been reported to show the atrophy of peripheral nerves on US. However, the US findings are still unclear in spinal and bulbar muscular atrophy (SBMA), an adult-onset lower motor neuron disease caused by an abnormal CAG repeat expansion in the androgen receptor gene. METHODS: We prospectively recruited and evaluated 11 patients with genetically confirmed SBMA and 9 patients with ALS diagnosed according to the revised El Escorial ALS criteria or the Awaji electrodiagnostic criteria. The C5-C7 cervical nerve roots and the median and ulnar nerves were evaluated ultrasonographically. RESULTS: The cross-sectional areas (CSAs) of the C6 and C7 nerve roots, the median nerve in the upper arm and forearm, and the ulnar nerve in the upper arm were smaller in patients with SBMA than those in patients with ALS (p < 0.05), whereas the CSAs of the C5 nerve root and the ulnar nerve in the forearm were not smaller. CONCLUSIONS: US showed that the peripheral nerves in patients with SBMA were thinner than those in patients with ALS despite similar degrees of weakness and motor neuron loss. Possible causes include additional sensory nerve involvement and longer disease duration in patients with SBMA than those in patients with ALS.

Spinal cord tethering after selective dorsal rhizotomy below the conus medullaris.

BACKGROUND: Two techniques for selective dorsal rhizotomy (SDR) involve stimulating and sectioning nerve rootlets either below the conus medullaris or above the entrances to their respective dural root sleeves. In general, both techniques lead to sustained improvements in lower extremity spasticity with low complication rates. To our knowledge, spinal cord tethering has not been previously reported as a complication of SDR using either technique. METHODS: We review the presentation, treatment, and outcome of two patients who developed symptomatic spinal cord tethering after SDR below the conus. RESULTS: A 4-year-old male and a 6-year-old female each with a history of spastic diparetic cerebral palsy underwent L1-L2 osteoplastic laminectomy and SDR below the conus. Both surgeries went well with no known complications. Both patients initially did well, with marked improvement in their tone and gait. There were no significant immediate postoperative bowel or bladder problems. The male patient presented 10 months after surgery with new-onset urinary incontinence. A urological evaluation was performed but no imaging was performed. He re-presented 8 months later with worsened urinary incontinence, new fecal incontinence, and worsened gait. An MRI showed signs of tethering, including a holocord syrinx. He underwent two untethering surgeries as well syrinx fenestration, and although his gait improved, it remained worse than it had been several months after surgery. The incontinence did not improve. The second patient also developed urinary incontinence a year after SDR. Due to our experience with the first patient, we obtained an MRI immediately and found evidence of tethering. She underwent untethering and her incontinence improved. CONCLUSION: We report two cases of spinal cord tethering after SDR below the conus, a previously unreported complication. It is important to realize that this complication can occur after SDR.

Nerve root morphological and functional changes after degenerative cervical myelopathy surgery: preliminary study using ultrasound and electrophysiology.

STUDY DESIGN: A prospective observational study. OBJECTIVES: To depict morphological and functional changes in the cervical nerve roots before and after spinal cord decompression surgery for degenerative cervical myelopathy (DCM). SETTING: A general hospital in Japan. METHODS: Thirteen DCM patients who underwent posterior spinal cord decompression surgery, laminoplasty or laminectomy, were included in this study. The neural foramen shown on MRI and the cross-sectional area (CSA) of the nerve roots on ultrasound were used to evaluate the C5 and C6 nerve roots. The compound muscle action potentials (CMAPs) of deltoid and biceps muscle were also recorded. RESULTS: All patients showed sensorimotor functional improvement without the postoperative C5 palsy after surgery. Foraminal stenosis and preoperative CSA of the nerve root: C4/5 foramen and C5 nerve root, C5/6 foramen and C6 nerve root, had no significant correlation (P = 0.53 and 0.08). CSA of the C5 nerve root displayed no significant change before and after surgery (P = 0.2), however, that of the C6 nerve root reduced significantly after surgery (P = 0.038). The amplitude of the deltoid and biceps CMAPs displayed no significant change before and after surgery (P = 0.05 and 0.05). CONCLUSION: The C6 nerve root CSA change was observed after spinal cord decompression surgery with functional recovery. However, deltoid and biceps CMAPs amplitude showed no significant change. Independent CSA changes on ultrasound might be useful when conducting a functional evaluation of the postoperative nerve root. SPONSORSHIP: The Grant of Japan Orthopaedics and Traumatology Research Foundation No. 395.

Advanced MRI imaging of nerve roots in lumbar radiculopathy due to discoradicular conflict: DWI, DTI, and T2 mapping with clinical and neurophysiological correlations.

PURPOSE: To evaluate the lumbar nerve root alterations in patients with lumbar disc herniation sciatica using advanced multimodality MRI sequences and the correlations with clinical and neurophysiological findings. MATERIAL AND METHODS: We prospectively evaluated 45 patients suffering from unilateral lumbar radiculopathy due to disco radicular conflict. All patients underwent MRI examinations using a standard MRI protocol and additional advanced MRI sequences (DWI, DTI, and T2 mapping sequences). Relative metrics of ADC, FA, and T2 relaxation times were recorded by placing ROIs at the pre-, foraminal, and post-foraminal level, either at the affected side or the contralateral side, used as control. All patients were also submitted to electromyography testing, recording the spontaneous activity, voluntary activity, F wave amplitude, latency, and motor evoked potentials (MEP) amplitude and latency, both at the level of the tibialis anterior and the gastrocnemius. Clinical features (diseases duration, pain, sensitivity, strength, osteotendinous reflexes) were also recorded. RESULTS: Among clinical features, we found a positive correlation of pain intensity with ADC values of the lumbar nerve roots. The presence of spontaneous activity was correlated with lower ADC values of the affected lumbar nerve root. F wave and MEP latency were correlated with decreased FA values at the foraminal level and increased values at the post-foraminal level. The same neurophysiological measures correlated positively with pre-foraminal T2 mapping values and negatively with post-foraminal T2 mapping values. Increased T2 mapping values at the foraminal level were correlated with disease duration. CONCLUSIONS: Evaluation of lumbar nerve roots using advanced MRI sequences may provide useful clinical information in patients with lumbar radiculopathy, potentially indicating active inflammation/myelinic damage (DTI, T2 mapping) and axonal damage/chronicity (DWI).

Predicting Healthy C5 Spinal Nerve Stumps Eligible for Grafting with MRI, Tinel Test, and Rhomboid Electromyography: A Retrospective Study of 295 Consecutive Brachial Plexus Surgeries.

Background MRI, Tinel test, and rhomboid electromyography (EMG) can be used to predict whether C5 spinal nerve stumps are healthy and eligible for grafting in acute adult brachial plexus injuries, but their comparative diagnostic efficacies have not been evaluated. Purpose To compare diagnostic performances of MRI, Tinel test, and rhomboid EMG in predicting healthy C5 spinal nerve stumps that are eligible for grafting. Materials and Methods This retrospective study included consecutive adult patients with acute brachial plexus injury who underwent microreconstructions between January 2008 and December 2018. Healthy C5 spinal nerve stumps eligible for grafting with preceding normal intradural nerve rootlets were diagnosed by an experienced neuroradiologist using an avulsion severity score system based on fast imaging employing steady-state acquisition or FIESTA neurography, which separates intradural nerve rootlets into normal, partial mild, severe, and complete avulsions. Tinel test and rhomboid EMG results were assessed by an experienced nerve surgeon and neurologist, respectively. The accuracy, sensitivity, and specificity of the three tests were compared using microdissection as the reference standard. P < .05 was considered to indicate a significant difference. Results A total of 251 patients (mean age, 31 years ± 13 [standard deviation]; 217 men) with brachial plexus injuries who had -undergone MRI (n = 251), Tinel test (n = 235), rhomboid EMG (n = 181) and MRI, Tinel test, and EMG (n = 172) were -included. Accuracy, sensitivity, and specificity, respectively, in predicting healthy C5 spinal nerve stumps eligible for grafting were 93% (233 of 251), 84% (58 of 69), and 96% (175 of 182) for MRI; 59% (139 of 235), 56% (37 of 66), and 60% (102 of 169) for Tinel test; and 39% (71 of 181), 85% (43 of 50), and 21% (28 of 131) for rhomboid EMG. MRI (area under the receiver operating characteristic curve [AUC], 0.90; P < .001) -outperformed MRI and Tinel test (AUC, 0.74), Tinel test (AUC, 0.59), and rhomboid EMG (AUC, 0.53). Conclusion MRI performed best in the prediction of healthy graftable C5 spinal nerve stumps in acute adult brachial plexus injuries. © RSNA, 2021 Online supplemental material is available for this article.

Cross-sectional area reference values for peripheral nerve ultrasound in adults: A systematic review and meta-analysis-Part III: Cervical nerve roots and vagal nerve.

BACKGROUND AND PURPOSE: Measurement of the cross-sectional area (CSA) of cervical nerve roots using ultrasound is useful in the evaluation of inflammatory polyneuropathies, and measurement of CSA of the vagal nerve might give information about involvement of the autonomic nervous system. We performed a systematic review and meta-analysis of published CSA reference values for cervical nerve roots and vagal nerve. METHODS: We included available-to-date nerve ultrasound studies on healthy adults and provide meta-analysis for CSA of the following nerves: cervical nerve roots C5, C6, and C7 as well as vagal nerve in the carotid sheath at the carotid bifurcation level. We report regression and correlation analyses for age, gender, height, weight, and geographic continent. RESULTS: We included 11 studies with 885 healthy volunteers (mean age = 42.7 years) and 3149 examined nerve sites. Calculated mean pooled CSA of C5 root was 5.6 mm2 (95% confidence interval [CI] = 4.6-6.7 mm2 , n = 911), of C6 root was 8.8 mm2 (95% CI = 7.4-10.3 mm2 , n = 909), of C7 root was 9.5 mm2 (95% CI = 8.0-10.9 mm2 , n = 909), and of vagal nerve was 2.2 mm2 (95% CI = 1.5-2.9 mm2 , n = 420). No heterogeneity was found across studies for any site. Subgroup analysis revealed no significant effects of age, gender, height, weight, and geographic continent on CSA for any of these nerve sites. CONCLUSIONS: We provide the first meta-analysis on CSA reference values for the cervical nerve roots and the vagal nerve, with no heterogeneity of reported CSA values at all nerve sites. Our data facilitate the goal of an international standardized evaluation protocol.

US-Guided Transforaminal Cervical Nerve Root Block: A Novel Lateral in-Plane Approach.

OBJECTIVE: The aim of the present study was to investigate the effectiveness and safety of a novel lateral in-plane approach for ultrasound-guided transforaminal cervical nerve root block (US-guided TF-CNRB) in the treatment of cervical radiculopathic pain. DESIGN: The design of the present study consisted of an institutional, retrospective case series. SETTING: The present study was conducted at a university hospital. SUBJECTS: Thirty-two patients with cervical radiculopathy who were resistant to conservative therapies and regular US-guided CNRB were included as participants. METHODS: The included patients were treated with US-guided TF-CNRB. During the treatments, using real-time fluoroscopy, we monitored the spreading patterns of a contrast medium and double confirmed the positions of needle tips. Pain numeric rating scales (NRS) and symptom relief grades were determined via telephone interviews at one, four, and 12 weeks after the procedures. RESULTS: US-guided TF-CNRB was performed at the C5 level in six patients, the C6 level in 18 patients, and the C7 level in eight patients. Compared with NRS at baseline, pain scores decreased throughout the observation period. Symptom relief rates of US-guided TF-CNRB at one, four, and 12 weeks were 72%, 69%, and 63%, respectively. Venous blood was aspirated during the procedures in two patients, and the needle tips were corrected. No intravascular injections or neurologic injuries were observed. CONCLUSION: US-guided TF-CNRB produced circumferential spreading around the involved cervical nerve root and showed significant clinical effectiveness in patients resistant to regular US-guided CNRB.