Outcomes after robotic thymectomy in nonthymomatous versus thymomatous patients with acetylcholine-receptor-antibody-associated myasthenia gravis.

The aim of this study was to investigate the surgical and long-term neurological outcomes of patients with acetylcholine-receptor-antibody-associated myasthenia gravis (AChR-MG) who underwent robotic thymectomy (RATS). We retrospectively analyzed the clinical-pathological data of all patients with AChR-MG who underwent RATS using the DaVinci® Robotic System at the MUMC+ between April 2004 and December 2018. Follow-up data were collected from 60 referring Dutch hospitals. In total, 230 myasthenic patients including 76 patients with a thymoma (33.0%) were enrolled in this study. Mean follow-up time, procedure time and hospitalization were, respectively 65.7 ± 43.1 months, 111±52.5 min and 3.3 ± 2.2 days. Thymomatous patients had significantly more frequently and more severe complications than nonthymomatous patients (18.4% vs. 3.9%, p<0.001). Follow up data was available in 71.7% of the included patients. The Myasthenia Gravis Foundation of America postintervention score showed any kind of improvement of MG-symptoms after RATS in 82.4% of the patients. Complete stable remission (CSR) or pharmacological remission (PR) of MG was observed in 8.4% and 39.4% of the patients, respectively. Mean time till CSR/PR remission after thymectomy was 26.2 ± 29.2 months. No statistical difference was found in remission or improvement in MGFA scale between thymomatous and nonthymomatous patients. RATS is safe and feasible in patients with MG. The majority of the patients (82.4%) improved after thymectomy. CSR and PR were observed in 8.4% and 39.4% of the patients, respectively, with a mean of 26.2 months after thymectomy. Thymomatous patients had more frequently and more severe complications compared to nonthymomatous patients.

Dutch injection versus surgery trial in patients with carpal tunnel syndrome (DISTRICTS): protocol of a randomised controlled trial comparing two treatment strategies.

INTRODUCTION: Carpal tunnel syndrome (CTS) is the most common peripheral neuropathy. The optimal treatment strategy is still unknown. The objective of the Dutch Injection versus Surgery TRIal in patients with CTS (DISTRICTS) is to investigate if initial surgery of CTS results in a better clinical outcome and is more cost-effective when compared with initial treatment with corticosteroid injection. METHODS AND ANALYSIS: The DISTRICTS is an ongoing multicenter, open-label randomised controlled trial. Participants with CTS are randomised to treatment with surgery or with a corticosteroid injection. If needed, any additional treatments after this first treatment are allowed and these are not dictated by the study protocol. The primary outcome is the difference between the groups in the proportion of participants recovered at 18 months. Recovery is defined as having no or mild symptoms as measured with the 6-item carpal tunnel symptoms scale. Secondary outcome measurements are among others: time to recovery, hand function, patient satisfaction, quality of life, additional treatments, adverse events, and use of care and health-related costs. ETHICS AND DISSEMINATION: The study was approved by the Medical Ethical Committee of the Amsterdam University Medical Centers (study number 2017-171). Study results will be disseminated in peer-reviewed journals and conferences. TRIAL REGISTRATION NUMBER: ISRCTN Registry: 13164336.

Expert consensus on the combined investigation of carpal tunnel syndrome with electrodiagnostic tests and neuromuscular ultrasound.

Expert consensus was sought to guide clinicians on the use of electrodiagnostic tests (EDX) and neuromuscular ultrasound (NMUS) in the investigation of suspected carpal tunnel syndrome (CTS). Consensus was achieved using the Delphi method via three consecutive anonymised surveys of 15 experts and was defined as rating agreement ≥ 80%. The panel agreed that combining EDX and NMUS is more informative than using each modality alone. NMUS adds value in patients with clinically suspected CTS with non-localizing or normal EDX, atypical EDX, failed CTS surgery, polyneuropathy, and CTS suspected to be secondary to structural pathology. The median nerve cross-sectional area should be measured at the site of maximal nerve enlargement, and the nerve should be scanned from mid-forearm to the palm. The group also identified those situations where the wrist-to-forearm area ratio and longitudinal scans of the median nerve should also be obtained. EDX should always be performed to quantify CTS severity and in individuals over age 70. This document is an initial step to guide clinicians on the combined investigation of CTS using EDX and NMUS, to be updated regularly with the emergence of new research.

Evidence-based guideline: Neuromuscular ultrasound for the diagnosis of ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: The purpose of this literature review is to develop an evidence-based guideline for the use of neuromuscular ultrasound in the diagnosis of ulnar neuropathy at the elbow (UNE). The proposed research question was: "In patients with suspected UNE, does ulnar nerve enlargement as measured with ultrasound accurately identify those patients with UNE?" METHODS: A systematic review and meta-analysis was performed, and studies were classified according to American Academy of Neurology criteria for rating articles for diagnostic accuracy. RESULTS: Based on Class I evidence in four studies, it is probable that neuromuscular ultrasound measurement of the ulnar nerve at the elbow, either of diameter or cross-sectional area (CSA), is accurate for the diagnosis of UNE. RECOMMENDATION: For patients with symptoms and signs suggestive of ulnar neuropathy, clinicians should offer ultrasonographic measurement of ulnar nerve cross-sectional area or diameter to confirm the diagnosis and localize the site of compression (Level B).

Expert consensus on the combined investigation of ulnar neuropathy at the elbow using electrodiagnostic tests and nerve ultrasound.

The addition of ultrasound (US) to electrodiagnostic (EDX) tests can significantly enhance the accuracy of testing for ulnar neuropathy at the elbow (UNE). We aimed to obtain expert consensus to guide clinicians on the combined use of EDX and US in UNE investigation. Consensus was achieved using the Delphi method. Two consecutive anonymised questionnaires were submitted to 15 experts, who were asked to choose their level of agreement with each statement. Consensus was pre-defined as ≥ 80% rating agreement. The experts concluded that all investigations of UNE should include both nerve conduction studies and US. There was consensus that US should include cross-sectional area measurement and assessment of nerve mobility at the elbow, and that the entire ulnar nerve should be imaged. This study defined expert opinion on the 'core' techniques that should be used routinely in the UNE investigation using EDX and US. Areas with lack of consensus highlighted some controversial issues in the current use of these diagnostic modalities and the need for future research. This document is an initial step to guide clinicians on the combined investigation of UNE using EDX and US, to be regularly updated as new research emerges.

Wrist Circumference-Dependent Upper Limit of Normal for the Cross-Sectional Area Is Superior Over a Fixed Cut-Off Value in Confirming the Clinical Diagnosis of Carpal Tunnel Syndrome.

Introduction: In confirming the clinical diagnosis of carpal tunnel syndrome (CTS), ultrasonography (US) is the recommended first diagnostic test in The Netherlands. One of the most important parameters for an abnormal US result is an increase of the CSA of the median nerve at the carpal tunnel inlet. An earlier study showed that a wrist-circumference dependent cut-off for the upper limit of normal of this CSA might be superior to a fixed cut-off of 11 mm2. In this study we compared three ultrasonography (US) parameters in three large Dutch hospitals. Methods: Patients with a clinical suspicion of CTS and with reasonable exclusion of other causes of their symptoms were prospectively included. A total number of 175 patients were analysed. The primary goal was to compare the number of wrists with an abnormal US result while using a fixed cut-off of 11 mm2 (FC), a wrist circumference-dependent cut-off (y = 0.88 * x-4, where y = ULN and x = wrist circumference in centimetres; abbreviated as WDC), and an intraneural flow related cut-off (IFC). Results: The WDC considered more US examinations to be abnormal (55.4%) than the FC (50.3%) did, as well as the IFC (46.9%), with a statistically significant difference of p = 0.035 and p = 0.001, respectively. The WDC detected 12 abnormal median nerves while the FC did not, and 18 while the IFC did not. The wrist circumference of the patients of these subgroups turned out to be significantly smaller (p < 0.001) when compared with the rest of the group. Conclusion: According to these study results, the wrist-circumference dependent cut-off value for the CSA of the median nerve at the wrist appears to have a higher sensitivity than either a fixed cut-off value of 11 mm2 or cut-off values based on intraneural flow, and may add most value in patients with a smaller wrist circumference.

In situ decompression vs conservative treatment for mild ulnar neuropathy at the elbow.

INTRODUCTION: The best treatment strategy for mild ulnar neuropathy at the elbow (UNE) is not known, due to lack of trials comparing surgery vs conservative treatment. METHODS: We recruited patients with clinical symptoms and signs of mild UNE and an electrophysiologically or sonographically confirmed diagnosis. Patients were randomly allocated to either in situ decompression or conservative treatment. The primary outcome was the proportion of patients with subjective symptom improvement at short-term (3 months) and long-term (6-12 months) follow-up. RESULTS: One hundred seventeen patients were included: 56 and 61 patients were allocated to surgery and conservative treatment, respectively. A larger proportion of surgically treated patients showed improvement at short-term follow-up (85% vs 50%; odds ratio, 5.6; P < .001), but no differences were observed at long-term follow-up. DISCUSSION: In situ decompression for mild UNE may result in faster relief of symptoms when compared with conservative treatment, but at long-term follow-up no differences were observed.

[Carpal tunnel syndrome: a clinical diagnosis]. / Carpaletunnelsyndroom, een klinische diagnose.

Carpal tunnel syndrome (CTS) is a clinical syndrome diagnosis. There is no universal reference test for diagnosing CTS. In case of a clinical presentation consistent with the typical characteristics of CTS, the diagnosis can be made without additional examinations. In that case, the physician may immediately proceed with a discussion of treatment options with the patient, using the CTS consultation card. Use of clinical provocation tests, questionnaires and hand diagrams is not advised due to their limited diagnostic value. Additional examinations are indicated when a patient does not have all typical characteristics of CTS or when in doubt about the diagnosis. If available, nerve ultrasonography is the test of preference but nerve conduction tests are a good alternative. From the perspective of quality of care, patient-friendliness and efficiency, it is recommended to make arrangements between primary and secondary care about the care process for patients suspected of having CTS.

A novel points system to predict the prognosis of ulnar neuropathy at the elbow.

INTRODUCTION: In this study we aimed to identify prognostic factors of ulnar neuropathy at the elbow (UNE) and developed a scoring system to establish the prognosis. METHODS: We collected baseline clinical, electrophysiologic, and ultrasonographic data from 2 cohorts. The outcomes for all patients were determined on follow-up. Prognostic factors were determined using single and multiple variable analyses. A points system was developed to determine the risk for an unfavorable outcome. RESULTS: Of the 220 patients with UNE 178 (81%) could be re-evaluated. Four variables were retained in the prediction model for a points system. An unfavorable outcome was associated with right-sided UNE, more severe weakness of the abductor digiti minimi (ADM), and more pronounced ulnar nerve thickening. A compound muscle action potential amplitude reduction across the elbow of ≥16% (particularly if ≥ 50%) was associated with a more favorable outcome. CONCLUSION: Outcome in UNE may be predicted by scoring 4 parameters. Muscle Nerve 55: 698-705, 2017.

Doppler sonography for the diagnosis of carpal tunnel syndrome: a critical review.

INTRODUCTION: Doppler sonography may detect increased intraneural blood flow of the median nerve in carpal tunnel syndrome (CTS). The purpose of this review is to critically evaluate the literature about the diagnostic value of increased intraneural flow detected by sonography in CTS Methods: Systematic review of studies published between 1985 and 2013. RESULTS: The 7 studies we found had considerable differences in study design and had methodological shortcomings. Doppler sonography had a median sensitivity of 72% (range, 41-95%) and a median specificity of 88% (range, 71-100%). Most studies could not compare the diagnostic value of sonography to that of electrophysiological studies, because the latter were often used as a reference test. CONCLUSIONS: Increased intraneural flow detected by Doppler sonography may be a promising diagnostic test for CTS, but further studies are needed before it can be implemented in clinical practice.

Sonographic incidence of ulnar nerve (sub)luxation and its associated clinical and electrodiagnostic characteristics.

INTRODUCTION: The aim of this study was to assess the presence of (sub)luxation of the ulnar nerve in patients with ulnar neuropathy at the elbow (UNE) compared with healthy controls (HC). We assessed its clinical patterns, electrodiagnostic, and sonographic characteristics. METHODS: Using high-resolution sonography, we studied the incidence of (sub)luxation in a cohort of 342 patients and 70 HC. RESULTS: Subluxation occurred in 14% and luxation in 6.7% of the UNE patients versus 5.7% and 5.7%, respectively, in HC (no significant differences). Pain at the elbow occurred more often in patients with (sub)luxation (P = 0.007). Electrodiagnostic and sonographic findings did not differ between patients with or without (sub)luxation. CONCLUSIONS: The incidence of ulnar nerve (sub)luxation between patients with UNE and HC does not differ. UNE patients with (sub)luxation do not have specific clinical or electrodiagnostic findings, apart from experiencing pain at the elbow more often.

Which ultrasonographic measure has the upper hand in ulnar neuropathy at the elbow?

OBJECTIVE: To compare the diagnostic accuracy of ultrasonographic ulnar nerve diameter, cross-sectional area (CSA) and swelling ratio measurement in ulnar neuropathy at the elbow (UNE). METHODS: Ultrasonographic diameter, CSA, and swelling ratio measurements were compared with a reference standard including clinical examination, electrophysiological studies, and follow-up in a prospective cohort of patients. All patients in whom a diagnosis of UNE was considered were eligible for the study. Reference values for ultrasonography were obtained in 73 healthy volunteers. RESULTS: Of 191 patients, 137 had UNE or probable UNE, while 54 had another condition and these were analysed as patient controls. Patients with UNE had a larger ulnar nerve diameter, CSA and swelling ratio than healthy controls and patient controls (p < 0.01). The diagnostic accuracies of these different measurements were comparable with a specificity of 78-87%, a positive predictive value of 87-90%, a sensitivity of 42-61% and negative predictive value of 37-44%. ROC-analysis for these measurements showed an area under the curve of 0.75-0.77. CONCLUSION: Ultrasonographic measurements of ulnar nerve diameter, CSA and swelling ratio have comparable diagnostic value, which was lower than reported previously. SIGNIFICANCE: Ultrasonographic ulnar nerve diameter, CSA and swelling ratio measurements are equally useful in diagnosing UNE.

Prognostic factors in carpal tunnel syndrome treated with a corticosteroid injection.

INTRODUCTION: Symptoms often return in patients with carpal tunnel syndrome (CTS) who are treated with a local corticosteroid injection. We aimed to determine prognostic factors for a successful long-term outcome. METHODS: We prospectively followed 113 patients who received an injection for CTS. Clinical, electrophysiological, and ultrasonographic tests were done at baseline, and clinical outcome was evaluated after 1, 3, 6, and 12 months. The primary outcome measure for success was no need for additional treatment (e.g., surgery) within 1 year. RESULTS: After 1 month, most patients improved, but after 12 months 67.4% had surgery. Patients with a successful outcome had a lower median nerve ultrasonographic cross-sectional area (CSA) at the pisiform bone, a lower swelling ratio, and a lower symptom severity score. CONCLUSIONS: Less pronounced median nerve swelling measured by ultrasonography may indicate a less severe stage of CTS, which is more likely to respond to treatment with a corticosteroid injection.

Ultrasonography in ulnar neuropathy at the elbow: a critical review.

INTRODUCTION: Ultrasonography of the ulnar nerve has been recommended as a useful additional test in ulnar neuropathy at the elbow (UNE). METHODS: We searched the literature and systemically reviewed all clinical trials in UNE. We also looked for articles about the normal sonoanatomy and specific causes of UNE. RESULTS: Seven of 14 clinical trials in UNE were suitable for further analysis. Ultrasonographic ulnar nerve size measurement appears to be a test with good diagnostic accuracy. The most frequently reported abnormality was an increased cross-sectional area of the ulnar nerve at the elbow. However, several studies had methodological flaws. In addition, the ultrasonographic techniques and study designs differed among the studies. There were a few other uncontrolled studies about the underlying causes of UNE. DISCUSSION: The role of ultrasonography in UNE seems promising but could not be firmly established. More prospective studies are needed, and we make several recommendations for further research.

Short-segment nerve conduction studies in ulnar neuropathy at the elbow.

The aim of the study was to assess the diagnostic value of short-segment nerve conduction studies (NCS) at 2-cm intervals from 4 cm above to 4 cm below the medial epicondyle in a large group of patients with ulnar neuropathy at the elbow (UNE). Furthermore, we wanted to compare electrodiagnostic and clinical findings. We evaluated 73 arms in 70 patients with UNE and observed the following abnormalities on short-segment NCS: focal conduction block (CB) in 1, focal CB with increased latency change in 34, and increased latency change alone in 25. Short-segment NCS had an additional localizing value in 28 arms of the 37 patients (76%) with motor conduction velocity (MCV) slowing across the elbow only or with nonlocalizing electrodiagnostic findings. The lesion was located above the elbow in 32 arms (53%), at the epicondyle in 16 arms (27%), and below the epicondyle in 12 (20%) of the 60 arms with focal CB or increased latency change on short-segment NCS. Patients with CB on routine and short-segment NCS had muscle weakness significantly more often than patients without CB. Thus, short-segment NCS are useful in localizing the lesion in patients with UNE and CB on routine NCS and have additional diagnostic value in patients with MCV slowing across the elbow or with nonlocalizing signs on routine nerve conduction studies. We recommend its use in all patients in whom UNE is suspected.

Clinical, electrodiagnostic, and sonographic studies in ulnar neuropathy at the elbow.

The aim of this study was to determine possible correlations between the clinical characteristics, electrophysiological features, and sonographic ulnar-nerve diameter in patients with ulnar neuropathy at the elbow (UNE). We prospectively performed clinical, electrodiagnostic, and sonographic studies in 102 patients having either purely sensory signs (35%) or sensorimotor signs (65%) of UNE. Nerve conduction studies had a sensitivity of 78%, and the addition of sonography increased this to 98%. The diagnostic value of both tests was not different among cases with and without motor deficit. Motor studies with recording from the abductor digiti minimi and first dorsal interosseous muscles were equally sensitive for the detection of conduction block or velocity slowing across the elbow, but the combination yielded more positive cases than when only one study was performed. There were modest negative correlations between the electrodiagnostic parameters and the sonographic ulnar-nerve diameter. Electrodiagnostically and sonographically, there were no significant differences between clinically pure sensory and mixed sensorimotor cases of UNE, except for electrodiagnostic findings suggesting loss of motor axons in cases with motor signs. Almost half the patients with only sensory signs had electromyographic evidence of motor axonal loss. We conclude that, although UNE is clinically heterogeneous, the electrophysiological and sonographic findings are fairly consistent despite the clinical manifestations.

Bilateral intraneural perineurioma presenting as ulnar neuropathy at the elbow.

We describe a 36-year-old woman with progressive bilateral ulnar neuropathy. Sonographic and magnetic resonance imaging studies revealed extensive focal ulnar nerve enlargement at the elbow. Histological studies gave evidence of an intraneural perineurioma. Because intraneural perineurioma usually appears as a single mass lesion at sites other than typical entrapment sites, this mode of presentation is unusual. We discuss the nature of this benign tumor and the differential diagnosis of nerve enlargement. Knowledge of possible causes of nerve thickening is crucial when performing imaging in patients with neuropathies.