Ultrasound Nerve Research Articles

Phrenic Nerve Sonography Alterations in Patients with ALS: Insight with Clinical and Neurophysiological Findings

Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder, and although the diagnosis is primarily based on clinical criteria, ENMG, as the “gold standard”, does not always show detectable changes. Therefore, our study suggests that alterations in echogenicity and heterogeneity of the phrenic nerve (PN) may serve as potential additional diagnostic tools for ALS. Methods: Our study included 32 patients in the ALS group and 64 individuals in the control group. Each participant underwent an interview and completed questionnaires to collect clinical and demographic data, including age, gender, height, body mass index (BMI), hip and waist circumference, duration of illness, ALS-FRS-R score, comorbidities, and medication use. Ultrasound examinations of the PN were performed by two authors using a high-resolution “Philips EPIQ 7” ultrasound machine equipped with a linear 4–18 MHz transducer. The ALS group participants underwent PN sonography and conduction examinations, arterial blood gas (ABG) analysis, respiratory function tests (RFT), and electroneuromyography (ENMG). Results: The study demonstrated that the phrenic nerve is significantly smaller on both sides in patients with ALS compared to the control group (p < 0.01). Changes in the homogeneity and echogenicity of the PN were also observed on both sides. On the right side, 43.8% of the nerves showed heterogeneity, 40.6% were isoechoic, and 21.9% were hyperechoic. On the left side, 59.4% of the nerves exhibited heterogeneity, 34.4% were isoechoic, and 28.1% were hyperechoic. Moreover, sonography on both sides showed significant correlation with ALS-FRS-R, COMPASS-31, and ENMG results. Conclusions: Our study highlights the importance of phrenic nerve ultrasound as a promising supplementary diagnostic tool for ALS. The significant differences in phrenic nerve size, echogenicity, and homogeneity between patients with ALS and the control group demonstrate that ultrasound imaging can detect morphological changes in the phrenic nerve. Incorporating phrenic nerve ultrasound into routine diagnostic protocols could improve early detection, enhance disease monitoring, and offer a more comprehensive understanding of the neurodegenerative processes in ALS.

Lower limb nerve ultrasound: A four-way comparison of acquired and inherited axonopathy, inherited neuronopathy and healthy controls.

In a recent study, we showed that nerve ultrasound of the upper limbs could distinguish inherited sensory neuronopathy from inherited axonopathy; surprisingly, no differences were found in the lower limb nerves. In this study, we compared lower limb nerve ultrasound measurements in inherited neuronopathy, inherited axonopathy, and acquired axonopathy. Tibial and sural nerve ultrasound cross-sectional areas (CSAs) of 34 healthy controls were retrospectively compared with those of three patient groups: 17 with cerebellar ataxia with neuronopathy and vestibular areflexia syndrome (CANVAS), 18 with Charcot-Marie-Tooth type 2 (CMT2), and 18 with acquired length-dependent sensorimotor axonal neuropathy, using ANOVA with post-hoc Tukey honestly significance difference (HSD) (significance level set at p < .05). The nerve CSAs of CANVAS and CMT2 patients were not significantly different. Both the tibial and the sural nerve CSAs were significantly smaller in CANVAS and CMT2 compared with the acquired axonal neuropathy group. Tibial nerve CSAs of CANVAS and CMT2 were significantly smaller than controls. Tibial and sural nerve CSAs of the acquired axonal neuropathy group were also significantly larger than the controls'. Ultrasound of the lower limb nerves distinguished inherited from acquired axonopathy with the nerve size respectively reduced and increased in these two groups. This has potential implication for the differential diagnosis of these diseases in clinical practice.

Nerve ultrasound in CANVAS-spectrum disease: Reduced nerve size distinguishes genetically confirmed CANVAS from other axonal polyneuropathies.

Ultrasound nerve cross-sectional area (CSA) of patients affected with axonal neuropathy usually shows normal value. Cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) seems to represent an exception, showing smaller CSA, but previous reports did not test for biallelic RFC1 gene repeat expansions. We compared nerve CSA from CANVAS patients (tested positive for biallelic RFC1 gene repeat expansions) with the CSA from a group of patients with chronic idiopathic axonal polyneuropathy (CIAP) who tested negative for RFC1 gene repeat expansions, hereditary axonal neuropathy (Charcot-Marie-Tooth type 2, CMT2), and Friedreich ataxia (FRDA). We enrolled 15 CANVAS patients (eight men, mean age 66.3 ± 11.5 years, mean disease duration 9.3 ± 4.1 years), affected with sensory axonal neuronopathy. Controls consisted of 13 CIAP (mean age 68.5 ± 12.8 years, seven men), seven CMT2 (mean age 47.9 ± 18.1 years, four men), 12 FRDA (mean age 33.7 ± 8.8, five men). Nerve ultrasound was performed at median, ulnar, sciatic, sural, and tibial nerves and brachial plexus, bilaterally. The nerve CSA from CANVAS patients was significantly smaller than the one from the other cohorts at several sites with significant and high accuracy at Receiver-operating characteristic (ROC) curve analyses. RFC1 AAGGG pentanucleotide expansion, disease duration, and disability did not correlate with CSA at any site, after Bonferroni correction. Decreased sonographic nerve sizes, in arms and legs, in patients with sensory neuropathy and normal motor conduction studies could point to CANVAS-spectrum disease and help guide appropriate genetic testing.

Assessing the severity of carpal tunnel syndrome during physical examination by measuring two-point discrimination: Post-hoc analysis of prospectively collected data

IntroductionCarpal tunnel syndrome (CTS) commonly presents after distal radius fractures. Assessing its degree of severity is essential to therapeutic decision-making - i.e. operative vs. conservative treatment. The role of the two-point discrimination (2PD) has not yet been evaluated as a potential indicator of severity during physical examination. Therefore, in our cross-sectional study, we aimed to find a correlation between 2PD values and disease severity, based on the gold-standard electromyography and electroneurography (EMG-ENG) and ultrasonography findings. MethodsWe conducted a post-hoc analysis of prospectively assessed CTS patients for 2PD values. We analyzed the correlation between 2PD and EMG-ENG measurement results, patient characteristics, nerve ultrasonography, and relevant CTS questionnaires. CTS severity was determined by EMG-ENG results. The Pearson correlation was calculated between variables. ResultsThe study included 81 patients. The three pre-determined EMG-ENG severity categories showed a significant correlation between both 2PD values and 2PD severity categories (r= 0.29 [0.07–0.48] and r= 0.26 [0.03–0.45]). Distal sensory latency and conduction velocity values correlated significantly with 2PD categories. However, the correlation coefficients (r= 0.25 [0.02–0.46] and r=-0.24 [-0.37–0.07]) were low. The 2PD severity categories showed no significant correlation with the severity assessed by nerve ultrasound (r=-0.07 [-0.38–0.25]). The 2PD values showed a significant correlation between the values of the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire (r= 0.3 [0.06–0.51]). We concluded that the best cut-off value for differentiating severe from non-severe CTS was at the 9.5 mm 2PD cut-off value (sensitivity = 0.65 [0.45–0.81], specificity = 0.71[0.58–0.82], AUC = 0.71 [0.59–0.83]). ConclusionThere is a significant correlation between 2PD values and the severity of carpal tunnel syndrome as determined by EMG-ENG; however, they are not interchangeable. Based on the results of our study, we propose that measuring two-point discrimination may be a quick and easy, reliable and cost-effective screening method to assess the severity of carpal tunnel syndrome following distal radius fractures.

Nerve sonography to detect intraneural microvascularity in patients with peripheral neuropathy

ObjectiveWe assessed microvessel flow within peripheral nerves using nerve sonography in patients with peripheral neuropathy. MethodsThis study included consecutive patients with peripheral neuropathy who were admitted to our hospital. The patients were divided into two groups: inflammatory neuropathies for immune-mediated neuropathies, such as Guillain − Barré syndrome and chronic inflammatory demyelinating polyneuropathy, and the rest were defined as non-inflammatory neuropathies. We assessed nerve size and intraneural blood flow at four sites on each median and ulnar nerve. Blood flow was evaluated using color Doppler imaging, advanced dynamic flow (ADF), and superb microvascular imaging (SMI) techniques. ResultsThirty-nine patients (median age, 60.0 years; 20 male) were enrolled in this study. An increase in intraneural blood flow was observed in five patients when evaluated by color Doppler, five patients by ADF, and 13 patients by SMI. An overall analysis of the three methods showed that intraneural blood flow was significantly higher in patients with inflammatory neuropathy than in those with non-inflammatory neuropathy (54.2% vs. 0%, p = 0.0005). ConclusionsIntraneural hypervascularization is more frequent in patients with inflammatory neuropathy than in those with non-inflammatory neuropathy. SignificanceEvaluation of microvessel flow within peripheral nerves may contribute to the diagnosis of peripheral neuropathy.

Diagnostic Accuracy of Optic Nerve Sheath Diameter Using Ultrasonography for Raised Intracranial Pressure in Pediatric Patients - A Systematic Review and Meta-Analysis

PurposeDetecting increased intracranial pressure early in pediatric patients is essential, as early initiation of therapy prevents morbidity and mortality. The objective of this study was to determine the diagnostic accuracy of the ONSD measured via ultrasound for the prediction of increased intracranial pressure. MethodsFour databases, namely, PubMed, EMBASE, Scopus & CINAHL, were searched for this systematic review and meta-analysis. The study's predefined inclusion criteria considered diagnostic accuracy, cross-sectional, prospective observational, and retrospective studies with a focus on children with elevated intracranial pressure from causes such as traumatic brain injury and cerebral edema, the diagnostic accuracy of the optic nerve sheath diameter measured using ultrasound was assessed. The primary outcome measures included sensitivity, specificity. The study included invasive monitoring (EVD) and noninvasive measures as the gold standards for increased intracranial pressure. Two authors extracted and reviewed the data. Baseline data, outcome measures, and diagnostic accuracy data were extracted. ResultsTwenty-five studies with 1,591 patients and 3,143 ONSD measurements via ultrasound were analyzed. The pooled sensitivity and specificity of the ONSD measured via ultrasound for the prediction of increased intracranial pressure were 92% (86–96%) and 89% (77–96%), respectively. The pooled positive and negative likelihood ratios were 8.6 and 0.08, respectively. Conclusion and RelevanceOptic nerve ultrasonography stands out as a precise and valuable diagnostic tool applicable across diverse patient populations and clinical scenarios. We recommend routine ocular ultrasound for optic nerve sheath diameter measurement in pediatric patients to increase the accuracy of diagnosing increased intracranial pressure.

A comparative study of ultrasonography versus peripheral nerve stimulator-guided obturator nerve block for transurethral resection of bladder tumor under spinal anesthesia

Background: Transurethral resection of bladder tumor (TURBT) is usually done spinal anesthesia but it does not prevent the obturator reflex leading to bladder perforation, bleeding, or incompletely resection of resection of the tumor which could be prevented by obturator nerve block (ONB) in TURBT. Aims and Objectives: The aim of our study is to compare the effectiveness of ONB by peripheral nerve stimulator (PNS) and ultrasonography (USG) in TURBT and also compare morbidity between USG- and PNS-guided ONB in TURBT under spinal anesthesia. Materials and Methods: Sixty patients were randomly divided into two groups. Group (1) patients had a PNS-guided ONB and Group (2) patients had ONB-guided ONB. The presence or absence of adductor muscles reflexes was recorded. Bladder perforation and bleeding during surgery were also recorded. Results: A success rate of 90% was achieved in the Group (2) compared to 66% in Group (1) which was clinically significant with P=0.049. Complete bladder perforation was detected in four patients in Group (1) whereas no perforation was observed in Group (2). Bleeding was observed in both groups but severe bleeding was present in five patients in Group (1) and required a blood transfusion. Conclusion: We concluded that USG-guided ONB is more efficient and safer as compared to PNS-guided ONB.

Experimental Analysis of Echogenic Signals Appearing in Optic Nerve Ultrasound.

Experimental Analysis of Echogenic Signals Appearing in Optic Nerve Ultrasound.

Nerve enlargement in patients with Noonan syndrome: A retrospective cohort study.

Noonan syndrome (NS) is an autosomal dominant condition characterized by facial dysmorphism, congenital heart disease, development delay, growth retardation and lymphatic disease. It is caused by germline pathogenic variants in genes encoding proteins in the Ras/mitogen-activated protein kinase signaling pathway. Nerve enlargement is not generally considered as a feature of NS, although some cases have been reported. High-resolution nerve ultrasound enables detailed anatomical assessment of peripheral nerves and can show enlarged nerves. This retrospective cohort study aims to describe the sonographic findings of patients with NS performed during a 1-year time period. Data on the degree of enlargement, the relation to increasing age, pain in extremities, genotype on the gene level and clinical features were collected. Twenty-nine of 93 patients visiting the NS Center of Expertise of the Radboud University Medical Center Nijmegen underwent high-resolution ultrasound. In 24 patients (83%) nerve enlargement was found. Most of them experienced pain. We observed a weak correlation with increasing age and the degree of nerve enlargement but no association with pain, genotype at the gene level or clinical features. This study shows that patients with NS have a high predisposition for sonographic nerve enlargement and that the majority experience pain.

CLINICAL AND INSTRUMENTAL PREDICTORS OF THE EFFICIENCY OF CONSERVATIVE AND OPERATIVE TREATMENT OF MEDIAN NERVE NEUROPATHY IN THE CARPAL TUNNEL

Introduction. Clinical and instrumental predictors of the efficiency of conservative and surgical treatment of median nerve neuropathy in the carpal tunnel still remain a topical issue. Aim. To identify clinical and instrumental predictors of clinical outcomes and patients’ satisfaction after conservative and surgical treatment of carpal tunnel syndrome. Materials and methods. Analysis of clinical outcomes and patients’ satisfaction in 93 cases with carpal tunnel syndrome: the first group included 49 patients (68 wrists) after conservative and the second group included 44 patients (50 wrists) after surgical treatment. To identify predictors of the efficiency of treatment, analyzed the following clinical-instrumental values: patients’ age, duration of the disease, discriminative sensation, pain intensity according to VAS, values of DASH, BCTQ, CTS scales, clinical stage by Hi-Ob scale, electromyography severity grade according to Bland J.D., nerve conduction study and sonography results. Results. The nerve conduction study and clinical examinations data (discriminative sensation, clinical stage, duration of the disease, BCTQ and DASH values) show reliable effects on clinical outcomes and patients’ satisfaction after conservative treatment. The sensory nerve action potential amplitude and electromyography severity grade have the highest prognostic accuracy (91.4% and 84.5% respectively) for poor (unsatisfactory) result. For surgical treatment, identified results of nerve conduction study, sonography, and patients' age show reliable effects on clinical outcomes and patients’ satisfaction. The values of the highest prognostic accuracy for poor (unsatisfactory) result were nerve deformity index established by sonography (77.8%) and thenar compound muscle action potential amplitude – by nerve conduction study (78.7%). Conclusions. We identified clinical-instrumental predictors of clinical outcomes and patients’ satisfaction after conservative and surgical treatment of carpal tunnel syndrome. Specific results of instrumental examination demonstrated excellent diagnostic quality and the highest prognostic accuracy.

Neurological features of Hansen disease: a retrospective, multicenter cohort study

To elucidate the neurological features of Hansen disease. The medical records of patients with confirmed Hansen disease transferred from the neurology department were reviewed, and all medical and neurological manifestations of Hansen disease were assessed. Eleven patients with confirmed Hansen disease, 10 with newly detected Hansen disease and 1 with relapsed Hansen disease, who visited neurology departments were enrolled. The newly detected patients with Hansen disease were classified as having lepromatous leprosy (LL, n = 1), borderline lepromatous leprosy (BL, n = 2), borderline leprosy (BB, n = 2), borderline tuberculoid leprosy (BT, n = 1), tuberculoid leprosy (TT, n = 2), or pure neural leprosy (PNL, n = 2). All of the patients with confirmed Hansen were diagnosed with peripheral neuropathy (100.00%, 11/11). The symptoms and signs presented were mainly limb numbness (100.00%, 11/11), sensory and motor dysfunction (100.00%, 11/11), decreased muscle strength (90.90%, 10/11), and skin lesions (81.81%, 9/11). Nerve morphological features in nerve ultrasonography (US) included peripheral nerve asymmetry and segmental thickening (100.00%, 9/9). For neuro-electrophysiology feature, the frequency of no response of sensory nerves was significantly higher than those of motor nerves [(51.21% 42/82) vs (24.70%, 21/85)(P = 0.0183*)] by electrodiagnostic (EDX) studies. Nerve histological features in nerve biopsy analysis included demyelination (100.00%, 5/5) and axonal damage (60.00%, 3/5). In addition to confirmed diagnoses by acid-fast bacteria (AFB) staining (54.54%, 6/11) and skin pathology analysis (100.00%, 8/8), serology and molecular technology were positive in 36.36% (4/11) and 100.00% (11/11) of confirmed patients of Hansen disease, respectively. It is not uncommon for patients of Hansen disease to visit neurology departments due to peripheral neuropathy. The main pathological features of affected nerves are demyelination and axonal damage. The combination of nerve US, EDX studies, nerve biopsy, and serological and molecular tests can improve the diagnosis of Hansen disease.

Cubital Tunnel Syndrome Due to Intraneural Ganglion Cysts of the Ulnar Nerve With Joint-Cyst Connection at the Elbow

BACKGROUND AND OBJECTIVES: The unifying articular theory suggests that intraneural ganglion cysts in the cubital tunnel arise from the elbow joint and are connected to the ulnar nerve through an articular branch. This study aimed to report our clinical experience with these cysts and our surgical findings and outcomes. METHODS: We retrospectively analyzed 13 patients who underwent surgery for cubital tunnel syndrome caused by an intraneural ganglion cyst of the ulnar nerve. Clinical symptoms, physical examination findings, nerve conduction testing electromyography, plain radiography, and ultrasonography were evaluated before and after surgery. MRI was performed in 2 patients. Cyst decompression, disconnection of the articular branch, and ulnar nerve transposition were performed in all. RESULTS: The mean follow-up was 29 months. After surgery, local elbow pain and Tinel sign disappeared in all patients, and the average Numerical Rating Scale dropped from 3.7 (2-5) to 0 (0-0). Two-point discrimination testing was normal (&lt;5.0 mm) in 12 patients. Wartenberg sign and “claw hand” deformity became negative, and muscle function and motor nerve conduction velocity were improved in 12 patients. The Medical Research Council muscle strength grade was M4 or M5 in the flexor carpi ulnaris, flexor digitorum profundus of the 4th and 5th digits, and first dorsal interosseous muscle in 12 patients. Postoperative spontaneous potentials including fibrillation and sharp waves, and motor unit recruitment in the first dorsal interosseous muscle were obviously improved. A cystic articular branch was confirmed during surgery in all patients. No cyst recurred clinically or on follow-up ultrasonography. CONCLUSION: The unifying articular theory of intraneural ganglion cysts applies to those located in the ulnar nerve at the elbow. Surgical disconnection of the articular nerve branch from the ulnar nerve eliminated the pathway for cyst recurrence and achieved good long-term outcomes.

The usefulness of ultrasonography for the early diagnosis of polyneuropathy in patients with type II diabetes mellitus

Background: Diabetic neuropathies, affecting over 50% of diabetes patients, present varied forms of polyneuropathy impacting somatic and autonomic nerves. Clinical assessments, laboratory findings, and nerve conduction studies (NCSs) aid in precise diagnosis, while recent technological advances highlight ultrasonography (US) as a promising, cost-effective diagnostic tool. Aims and Objectives: This study aims to assess the efficacy of US in early polyneuropathy diagnosis in type II diabetes, exploring its potential as an alternative to NCS. Materials and Methods: In this prospective observational study, we enrolled 30 adult patients with type II non-controlled diabetes and 30 age-matched controls, comprising 15 controlled diabetic patients and 15 normal individuals. The comprehensive assessments encompassed history-taking for diabetes duration, hypertension, and diabetic complications, along with clinical examinations and investigations involving nerve electrophysiology and US on one upper limb based on patient complaints. Results: Significant increases in the cross-sectional area (CSA) of the median nerve were observed in diabetic peripheral neuropathy groups compared to controls, with a P&lt;0.001. Similarly, at the level behind the medial epicondyle, the ulnar nerve CSA exhibited a significant increase in the diabetic peripheral neuropathy group (11.7 mm2) compared to controls (6.7 mm2) with a P&lt;0.002. In addition, a significant difference in cross-sectional values was found in the median nerve proximal to the carpal tunnel between the two groups (P&lt;0.05). In contrast, no significant differences were observed at other sites. Regarding the relationship between sonography and NCSs, NCSs showed higher sensitivity, but sonography demonstrated comparable specificity in evaluating diabetic peripheral neuropathy. Conclusion: Peripheral nerve US in the upper limb can be a valuable diagnostic tool for identifying and diagnosing diabetic peripheral neuropathy.

Characteristics of Patients with Clinical Signs and Symptoms of Carpal Tunnel Syndrome but Negative Diagnostic Testing.

Carpal tunnel syndrome (CTS) is a clinical diagnosis involving numerous confirmatory diagnostic tools, including patient questionnaires, ultrasound (US), and electrodiagnostic studies (EDX.) Patients may experience clinical symptoms of CTS with false negative diagnostic testing. The purpose of this study was to identify characteristics of patients with clinical symptoms of CTS with negative diagnostic testing. An existing database of 295 hands containing the six-item CTS-6, US of the median nerve, and EDX was queried. Patients with symptoms of carpal tunnel scoring 12.5 or higher on CTS-6 were sorted into those with all positive testing or negative testing. In 60 patients, 103 hands had both positive US and EDX and a CTS-6 of 12.5 or higher. Twenty-nine hands in 25 patients had a CTS-6 of 12.5 or higher and both negative ultrasound and EDX. There was a significantly younger average age of 43 (P = 0.007) and lower average BMI of 28 (P < 0.0001) of patients in the negative diagnostic study group, compared with the average age of 53, and a body mass index (BMI) of 34 in the positive diagnostic study. In this series, patients with symptoms of carpal tunnel syndrome and negative diagnostic studies were on average younger and had a lower BMI. These patients may warrant more careful consideration of CTS clinical diagnosis and counseling regarding a higher risk of false-negative confirmatory testing. Further studies are needed to determine possible effects of age and BMI on electrodiagnostic studies and ultrasound testing in CTS.

A rare case with atypical findings: schwannoma of the radial nerve

A 53-year-old male complained of weakness in the dorsum of the 5-4-3rd fingers of the right hand. The musculus extensor digitorum communis was heavy and the musculus extensor indices proprius was light involved in the needle electroneuromyography study. Radial nerve ultrasonography showed a mass(schwannoma) which located on the radial nerve course after the lateral epicondyle at the elbow level. In conclusion, we should consider radial nerve schwannoma in patients with radial nerve injury and when there is an atypical involvement of the muscles innervated by the radial nerve, we should utilize ultrasonography for evaluation.

Diagnostic value of lower extremity ultrasonographic nerve enlargement for differentiating demyelinating Charcot-Marie-Tooth disease from chronic inflammatory demyelinating polyneuropathy

Background and purposeWe previously reported that nerve enlargement assessment by nerve ultrasonography of the intermediate upper limb is applicable for distinguishing demyelinating Charcot-Marie-Tooth disease (CMT) from chronic inflammatory demyelinating polyneuropathy (CIDP). However, differences in the severity and distribution patterns of lower extremity nerve enlargement have not been established for either disease. Therefore, we examined the utility of lower extremity nerve ultrasonography for differentiating between CMT and CIDP. MethodsTwelve patients with demyelinating CMT and 17 patients with CIDP were evaluated. The median, ulnar, tibial, and fibular nerves were evaluated in three regions: the distal upper extremity, intermediate upper extremity, and lower extremity. Of the 14 selected screening sites, the number of sites that exhibited nerve enlargement (enlargement site number, ESN) in each region was determined. ResultsThe screening ESNs in the intermediate region and lower extremities were greater in patients with demyelinating CMT than in patients with CIDP and greater than the ESN in the distal region (p = 0.010, p = 0.001, and p = 0.101, respectively). The ESNs in the intermediate region and lower extremities significantly differed among patients with typical CIDP, CIDP variants, and demyelinating CMT (p = 0.084 and p < 0.001). Among the 14 selected screening sites, the combined upper and lower extremity ESNs exhibited the highest AUC (0.92; p < 0.001). ConclusionsCombining the upper and lower extremities for ultrasonographic nerve measurement more accurately distinguishes CIDP from demyelinating CMT.

Ultrasound of the Ulnar Nerve: A Pictorial Review: Part 2: Pathological Ultrasound Findings.

This is the second part of a two-part article in which we focus on the ultrasound (US) appearance of the pathological ulnar nerve (UN) and its main branches. Findings in a wide range of our pathological cases are presented with high-resolution US images obtained with the latest-generation US machines and transducers.

Electrophysiological studies versus high-resolution nerve ultrasound in diagnosis of Guillain–Barré syndrome

Abstract Background Guillain–Barré syndrome (GBS) is polyneuropathy characterized by inflammation and immune-mediated processes that is classified into many subtypes based on electrophysiological and pathological criteria. The diagnosis of GBS can be confirmed using electrophysiological studies. However, electrophysiological studies may be normal when carried out early within 1 week in the course of the disease (Berciano et al. in J Neurol 264:221–236, 2017). One of the most useful imaging modalities for peripheral nerve diseases is ultrasonography (US). Nerve US in combination with electrophysiological studies provides an appropriate method in evaluating diseased peripheral nerves. This study aimed to enhance the reliability of early GBS diagnosis by correlating the findings of electrophysiological studies and nerve ultrasound. The nerve conduction studies (NCSs) in 37 GBS patients and 37 controls combined with cross-sectional area (CSA) assessment with US within the first 3 days of onset of symptoms and on day 14 after disease onset were evaluated. Results At presentation, patients and controls did not differ significantly in NCS parameters (p ≥ 0.05) except for a significantly longer F-wave minimum latency in the median, ulnar, and tibial nerves in patients (p &lt; 0.001). While on day 14 all NCS parameters differed significantly in patients in comparison to controls (p &lt; 0.001) with exception of the sural nerve parameters (p ≥ 0.05). Except for the sural nerve (p ≥ 0.05), all the examined nerves' CSAs were considerably higher in patients at presentation and on day 14 in comparison to the controls (p &lt; 0.001). The subtypes of Guillain–Barré syndrome either demyelinating, axonal or mixed axonal and demyelinating did not significantly differ regarding the CSAs of all the examined nerves either at presentation or on day 14 (p &gt; 0.05). Conclusion Electrophysiological results in GBS are crucial in diagnosing the disease and understanding its pathophysiology, but serial NCSs are required. Ultrasound shows structural aspects of the nerve, so ultrasonography is a reliable tool which can be used in diagnosis and follow-up of early GBS. As a result, combining the two investigations has a complementary effect in the diagnosis and prognosis of GBS.

Neuromuscular ultrasound in combination with nerve conduction studies helps identify inflammatory motor neuropathies from lower motor neuron syndromes.

Identifying patients with inflammatory motor neuropathies (IMNs) is warranted since effective treatments are available and the prognosis of these patients differs from that of amyotrophic lateral sclerosis patients. Between January 2019 and May 2022, 102 consecutive treatment-naïve lower motor neuron syndrome (LMNS) patients were recruited; these patients were suspected of having multifocal motor neuropathy, pure motor chronic inflammatory demyelinating polyneuropathy or amyotrophic lateral sclerosis with initial lower motor neuron presentation. Neuromuscular ultrasound (US) and nerve conduction studies (NCSs) were conducted at baseline. Relevant diagnostic investigations were performed if clinically warranted. The proposed US evidence of IMN was as follows: (i) nerve enlargement at ≥1 of the predetermined sites or (ii) absence of high intensity fasciculations in predefined muscle groups. Final diagnoses were made by experienced physicians after a prolonged follow-up period (≥12 months). IMN patients were defined as LMNS patients who experienced convincing improvements in response to immunotherapies. IMN patients without electrodiagnostic demyelinating features were diagnosed with treatment-responsive LMNS (TR-LMNS). In total, 16 patients were classified as IMN, including nine chronic inflammatory demyelinating polyneuropathy/multifocal motor neuropathy patients and seven TR-LMNS patients. Six TR-LMNS patients were identified by neuromuscular US. The sensitivity and specificity of NCSs, nerve US and muscle US were 56.3% and 100%, 43.8% and 90.7% and 68.8% and 97.7%, respectively. When these three modalities were combined, the sensitivity and specificity were 93.8% and 88.4%, respectively. Neuromuscular US studies are supplementary modalities to NCSs, and the combined use of these techniques might improve the identification of IMNs in LMNS patients.

Progress in the nerve ultrasound of inflammatory peripheral neuropathies

Objective: In recent years, high-resolution nerve ultrasound has been increasingly used as a complementary tool to nerve conduction studies in the diagnosis of peripheral neuropathies. Inflammatory peripheral neuropathies include a heterogeneous group of neuropathies mainly including chronic inflammatory demyelinating polyneuropathies (CIDP), multifocal motor neuropathy (MMN), systemic vasculitic neuropathy (SVN), and Guillain-Barre syndrome (GBS). We describe the ultrasonic characteristics of different inflammatory neuropathies.&#x0D; Data sources and study selection: The MEDLINE database was searched to find studies on nerve sonography in inflammatory peripheral neuropathies. Reported studies up to December 2022 were included in this review.&#x0D; Results: In neuropathies, the changes in ultrasound include enlarged nerve size, nerve echo-intensity, fascicle diameter and vascularity. Most CIDP patients have moderately enlarged CSA, some have dramatically enlarged CSA, and few have CSA within the normal range. Since the enlargement patterns are different, ultrasound is useful to help differentiate CIDP from CMT1. In follow-ups after immune treatment, nerve CSAs in CIDP could decrease, increase, or remain unchanged. Regional enlargement next to normal segments predominated in MMN. Nerve enlargement and hyper vascularization were found in vasculitic neuropathy. In GBS patients, there were enlarged peripheral nerve and nerve roots, which became normal at follow-up.&#x0D; Conclusions: High-resolution nerve ultrasound is complementary to the diagnosis of inflammatory peripheral neuropathies. CSA enlargement and its distribution are the most useful and quantifiable parameters in the evaluation of peripheral nerves. For patients suspected to have inflammatory neuropathies, we advise measuring the CSA of several pre-determined sites in the median, ulnar nerve, C5-8 cervical roots, and brachial plexus.