Fascicular Involvement of the Median Nerve Trunk in the Upper Arm: Manifestation as Anterior Interosseous Nerve Syndrome With Unique Imaging Features.

Selective fascicular involvement of the median nerve trunk above the elbow leading to anterior interosseous nerve (AIN) syndrome is a rare form of peripheral neuropathy. This condition has recently garnered increased attention within the medical community owing to advancements in imaging techniques and a growing number of reported cases. In this article, we explore the topographical anatomy of the median nerve trunk and the clinical features associated with AIN palsy. Our focus extends to unique manifestations captured through MRI and ultrasonography (US) studies, highlighting noteworthy findings, such as nerve fascicle swelling, incomplete constrictions, hourglass-like constrictions, and torsions, particularly in the posterior/posteromedial region of the median nerve. Surgical observations have further enhanced the understanding of this complex neuropathic condition. High-resolution MRI not only reveals denervation changes in the AIN and median nerve territories but also illuminates these alterations without the presence of compressing structures. The pivotal roles of high-resolution MRI and US in diagnosing this condition and guiding the formulation of an optimal treatment strategy are emphasized.

Concurrent spinal and brain imaging with optically pumped magnetometers.

BACKGROUND: The spinal cord and its interactions with the brain are fundamental for movement control and somatosensation. However, brain and spinal electrophysiology in humans have largely been treated as distinct enterprises, in part due to the relative inaccessibility of the spinal cord. Consequently, there is a dearth of knowledge on human spinal electrophysiology, including the multiple pathologies that affect the spinal cord as well as the brain. NEW METHOD: Here we exploit recent advances in the development of wearable optically pumped magnetometers (OPMs) which can be flexibly arranged to provide coverage of both the spinal cord and the brain in relatively unconstrained environments. This system for magnetospinoencephalography (MSEG) measures both spinal and cortical signals simultaneously by employing custom-made scanning casts. RESULTS: We evidence the utility of such a system by recording spinal and cortical evoked responses to median nerve stimulation at the wrist. MSEG revealed early (10 - 15 ms) and late (>20 ms) responses at the spinal cord, in addition to typical cortical evoked responses (i.e., N20). COMPARISON WITH EXISTING METHODS: Early spinal evoked responses detected were in line with conventional somatosensory evoked potential recordings. CONCLUSION: This MSEG system demonstrates the novel ability for concurrent non-invasive millisecond imaging of brain and spinal cord.

Lipofibromatous Hamartoma of the Median Nerve - A Rare Condition in the Hand.

Lipofibromatous hamartoma (LFH) of the median nerve is a rare condition in the hand and often remains asymptomatic for a significant period. MRI imaging can reveal unique tumour characteristics; however, the definitive diagnosis is confirmed through a tissue biopsy. In this report, a 38-year-old male presented with a gradually growing mass on his right hand. Physical examination revealed a large soft tissue mass extending from the thenar area to the wrist, causing compression of the median nerve. MRI confirmed the presence of a distinct soft tissue mass on the volar side of the hand. The mass was excised along with a fascicle and confirmed by histological examination. One year after surgery, sensation has improved, but weakness remains and opponensplasty was offered to the patient. Although the treatment strategy of LFH of the median nerve remains controversial, delayed treatment can result in severe compressive neuropathy and irreversible nerve damage. Level of Evidence: Level V (Therapeutic).

[MR neurography reveals fascicular constriction of the median nerve in a patient with neuralgic amyotrophy].

Diagnosing neuralgic amyotrophy can be challenging in clinical practice. Here, we report the case of a 37-years old Japanese woman who suddenly developed neuropathic pain in the right upper limb after influenza vaccination. The pain, especially at night, was severe and unrelenting, which disturbed her sleep. However, X-ray and MRI did not reveal any fractures or muscle injuries, and brain MRI did not reveal any abnormalities. During neurological consultation, she was in a posture of flexion at the elbow and adduction at the shoulder. Manual muscle testing suggested weakness of the flexor pollicis longus, pronator quadratus, flexor carpi radialis (FCR), and pronator teres (PT), while the flexor digitorum profundus was intact. Medical history and neurological examination suggested neuralgic amyotrophy, particularly anterior interosseous nerve syndrome (AINS) with PT/FCR involvement. Innervation patterns on muscle MRI were compatible with the clinical findings. Conservative treatment with pain medication and oral corticosteroids relieved the pain to minimum discomfort, whereas weakness remained for approximately 3 months. For surgical exploration, lesions above the elbow and fascicles of the median nerve before branching to the PT/FCR were indicated on neurological examinations; thus, we performed high-resolution imaging to detect possible pathognomonic fascicular constrictions. While fascicular constrictions were not evident on ultrasonography, MR neurography indicated fascicular constriction proximal to the elbow joint line, of which the medial topographical regions of the median nerve were abnormally enlarged and showed marked hyperintensity on short-tau inversion recovery. In patients with AINS, when spontaneous regeneration cannot be expected, timely surgical exploration should be considered for a good outcome. In our case, MR neurography was a useful modality for assessing fascicular constrictions when the imaging protocols were appropriately optimized based on clinical assessment.

Time-varying changes in median nerve deformation and position in response to quantified pinch and grip forces.

The ability of the median nerve (MN) to adapt in response to altered carpal tunnel conditions is important to mitigate compressive stress on the nerve. We assessed changes in MN deformation and position throughout the entire time course of hand force exertions. Fourteen right-handed participants ramped up force from 0% to 50% of maximal voluntary force (MVF) before ramping force back down in three different hand force exertion tasks (pulp pinch, chuck pinch, power grip). Pinch and grip forces were measured with a digital dynamometer, which were time synchronized with transverse carpal tunnel images obtained via ultrasound. Ultrasound images were extracted in 10% increments between 0% and 50% MVF while ramping force up (loading phase) and down (unloading phase). MN deformation and position relative to the flexor digitorum superficialis tendon of the long finger were assessed in concert. During loading, the nerve became more circular while displacing dorsally and ulnarly. These changes primarily occurred at the beginning of the hand force exertions while ramping force up from 0% to 20%, with very little change between 20% and 50% MVF. Interestingly, deformation and position changes during loading were not completely reversed during unloading while ramping force down. These findings indicate an initial reorganization of carpal tunnel structures. Mirrored changes in nerve deformation and position may also reflect strain-related characteristics of adjoining subsynovial connective tissue. Regardless, time-varying changes in nerve deformation and position appear to be an important accommodative mechanism in the healthy carpal tunnel in response to gripping and pinching tasks.

Subjective and Objective Differences in Patients with Unilateral and Bilateral Carpal Tunnel Syndrome and the Role of Obesity in Syndrome Severity.

BACKGROUND: It remains unclear whether physiologic differences exist in musculoskeletal ultrasound nerve measurements when comparing bilateral and unilateral carpal tunnel syndrome (CTS) patients. Similarly, the influence of body mass index on CTS severity is not well characterized. METHODS: Unilateral and bilateral CTS patients were seen from October of 2014 to February of 2021. Obese and nonobese CTS patients were compared. Median nerve cross-sectional area (CSA), Boston Carpal Tunnel Syndrome Questionnaire (BCTSQ), and six-item Carpal Tunnel Symptom Score (CTS-6) measures were obtained. Nerve conduction studies recorded distal motor latency (DML) and distal sensory latency (DSL). Statistical analysis used Wilcoxon signed rank testing for paired continuous variables, Mann-Whitney U testing for nonpaired continuous variables, and chi-square testing for continuous variables, with a significance level of P < 0.05. RESULTS: A total of 109 (218 nerves) bilateral and 112 (112 nerves) unilateral CTS patients were reviewed. Bilateral patients had larger median nerve CSAs on their more symptomatic side, when defined by BCTSQ score ( P < 0.0001), CTS-6 score ( P < 0.0001), DML ( P < 0.0001), and DSL ( P < 0.01). Bilateral patients also had higher symptom severity scale ( P < 0.01) and DSL ( P < 0.001) outcomes compared with unilateral patients. Obese patients had higher median nerve CSA ( P < 0.01), prolonged DML, and prolonged DSL ( P < 0.0001) values despite similar CTS severity (BCTSQ and CTS-6). CONCLUSIONS: Ultrasound identifies the more symptomatic side in bilateral patients, which correlates with increasing severity (NCS and BCTSQ). Obesity increases median nerve CSA and prolongs nerve conduction studies without influencing CTS severity. This information can be used when considering which diagnostic test to order for CTS.

Identifying anatomic landmarks and median nerve characteristics for the analysis of persistent carpal tunnel syndrome using magnetic resonance imaging (MRI).

OBJECTIVE: Carpal tunnel syndrome (CTS) is the most common nerve entrapment neuropathy in the USA. In this study, we define anatomical landmarks to assess symptomatic and asymptomatic cohorts with persistent CTS using MRI imaging. MATERIALS AND METHODS: Distal vs proximal incomplete release was determined using the distal most aspect of the hook of hamate and the distal wrist crease. An incomplete release showed the transverse carpal ligament (TCL) intact at either boundary. Twenty-one patients with persistent CTS were analyzed for incomplete release, median nerve enlargement and T2 signal hyperintensity, and flattening ratio using postoperative wrist MRI. These findings were compared to a ten-patient asymptomatic persistent CTS control group. Fisher's exact and a Student's two-tailed t-tests were used to determine statistical significance. RESULTS: In the symptomatic persistent CTS group, 13 (61.9%) incomplete releases were identified, 5 (38.5%) incomplete distally, and 1 (7.7%) incomplete proximally. There was no statistical significance in the rate of incomplete releases when compared to the asymptomatic group (p = 1.00). T2 signal hyperintensity and enlargement at the site of release showed no statistical significance, (p = 0.319 and p = 0.999, respectively). The mean flattening ratio at the site of release in the symptomatic group (2.45 ± 0.7) was statistically significant compared to the asymptomatic group (1.48 ± 0.46), (p = 0.007). CONCLUSION: Utilizing the established landmarks, the full length of the TCL can be assessed via MRI. Additionally, evaluation of the median nerve flattening ratio at the level of the incomplete release may be utilized as an aid to the clinical management of persistent CTS.

Utility of shear wave elastography for diagnosing carpal tunnel syndrome with psoriatic arthritis.

BACKGROUND: Carpal tunnel syndrome (CTS) is a type of peripheral entrapment neuropathy and common for the patients with psoriatic arthritis (PsA). Shear wave elastography (SWE) is a new ultrasonography technique that can be used for diagnosing CTS, but not studied in PsA patients. AIMS: The aim of this study to measure the stiffness of median nerve and hand muscles by quantitative SWE to identify whether SWE can be used for diagnosing CTS in patients with PsA or not. METHODS: To diagnose CTS, all patients had electrodiagnostic study. The stiffness values of the median nerve, abductor pollicis brevis, and abductor digiti minimi were determined using SWE. Muscle stiffness ratio was also calculated. RESULTS: Consideration is given to 48 patients with PsA (93 wrists) and 29 healthy volunteers (57 wrists). Median nerve stiffness was found to be significantly higher, and abductor pollicis brevis' stiffness and muscle stiffness ratio were significantly lower in PsA patients' wrists compared to control group (p = 0.002, p < 0.001, p = 0.001, respectively) and in CTS wrists compared to others (p < 0.001, p < 0.001, p = 0.001, respectively). Receiver operating characteristic analysis identified 28.2 kPA as the median nerve stiffness cut-off point for differentiating CTS in PsA patients (p = 0.001). CONCLUSIONS: We found that SWE has a good diagnostic value for CTS with PsA patients; hence, we can conclude that SWE could diagnose CTS in PsA patients.

Assessment of the carpal tunnel and associated neural structures with superb microvascular imaging: a scoping review.

INTRODUCTION: Superb microvascular imaging (SMI) is an advanced ultrasound technique that portrays microcirculation. Its clinical applications have been studied in various diseases, including carpal tunnel syndrome (CTS) i.e. the most common entrapment neuropathy. This scoping review explores the role of SMI in diagnosing CTS or the assessment of relevant neural structures. METHODS: We conducted a comprehensive search of electronic databases (PubMed, Embase and Web of Science) up to 26 September 2023. Two independent authors conducted the literature search, quality assessment, and data extraction. RESULTS: This review includes seven studies comprising 385 wrists. SMI consistently revealed increased intraneural vascularity in the median nerves of patients with CTS compared to healthy individuals. While SMI demonstrated higher sensitivity than traditional Doppler methods for detecting CTS, its specificity was somewhat lower. Combining SMI with B-mode ultrasound appears to enhance the diagnostic accuracy for CTS. However, the relationship between SMI findings and CTS severity remains unclear. CONCLUSIONS: This review highlighted the ability of SMI to provide detailed vascular structures in both healthy wrists and those with CTS. Additional research is crucial to determine the typical SMI findings of the carpal tunnel and within that context, tailor more precise diagnostic/therapeutic applications for the CTS population.

Volume Effect of Nerve Hydrodissection for Carpal Tunnel Syndrome: A Prospective, Randomized, and Single-Blind Study.

OBJECTIVES: This study compared ultrasound-guided nerve hydrodissection (HD) outcomes using two commonly used injectate volumes (10 and 5 mL) of normal saline to explore if there is a volume effect of HD for patients with moderate carpal tunnel syndrome (CTS). METHODS: Twenty-four participants were randomly assigned to treatment with HD using ultrasound-guidance and either 10 mL or 5 mL of normal saline (HD-10 and HD-5 groups respectively). Our primary outcome measures were the change scores of the two subscales of the Boston Carpal Tunnel Syndrome Questionnaire: The Symptom Severity Scale (SSS) and Functional Status Scale (FSS). We conducted a one-way repeated analysis of variance for 3 time points (4, 12, and 24 weeks) for both SSS and FSS, respectively, for change scores from time 0, and percentage change from time 0. RESULTS: All participants (n = 12 per group) completed the study. From 0 to 24 weeks the HD-10 group outperformed the HD-5 group for improvement in SSS (median ± IQR; -0.8 ± 0.4 versus -0.5 ± 0.5; P = .024) and FSS scores (mean ± SD; -0.8 ± 0.2 versus -0.5 ± 0.5; P = .011). The HD-10 group improvement in FSS subtest significantly exceeded the MCID percentage-change-based threshold of 27% (34%; P = .039). CONCLUSIONS: Despite the limitations of small study size, a largely inert injectate, and a single injection approach, these findings in favor of the 10 mL group suggest that the volume used for ultrasound-guided HD in moderate CTS matters, and a higher volume is more effective.

Elevated intraneural vascularization of the median nerve proximal to the arteriovenous fistula in hemodialysis patients suspected of carpal tunnel syndrome: A case series.

Patients with end-stage kidney disease may require creation of an arteriovenous fistula in order to receive hemodialysis treatment. The creation may result in several complications, including carpal tunnel syndrome. Early diagnosis and treatment are essential to relieve symptoms, prevent permanent nerve damage, and improve quality of life. However, the sensory and motor disturbances resembling carpal tunnel syndrome could be related to other etiologies than external compression of the median nerve underneath the transverse ligament. This case report presents eight patients with a radiocephalic arteriovenous fistula, who all had symptoms of carpal tunnel syndrome. Ultrasonographic examination showed a segmental intraneural hypervascularization of a large vessel inside the median nerve proximal to the wrist and arteriovenous fistula anastomosis with garland-like course as well as multiple flow velocities. The neurophysiological findings showed a significant decreased velocity in the ipsilateral forearm to the arteriovenous fistula.

[Analysis of the echographic parameters described in the study of carpal tunnel syndrome: A systematic review]. / Análisis de los parámetros ecográficos descritos en el estudio del síndrome del túnel del carpo. Una revisión sistemática.

Carpal tunnel syndrome (CTS) is the most common entrapment mononeuropathy; the diagnosis is established by electrodiagnostic tests with until 34% of false positives/negatives. We present the following systematic review which objective is to analyze the most recent literature related to the ultrasound parameters described to study CTS. We selected studies that evaluated ultrasound parameters in patients with clinical suspicion following the Cochrane manual's recommendations. We include systematic reviews, meta-analyses, case-control studies and diagnostic tests, evaluating retrospective studies and bibliographic reviews with proper methodological quality. Articles published between 2005 and 2019. We included eight articles (two systematic reviews/meta-analyses, two case-control studies, one diagnostic test study, two literature reviews, and one retrospective). The parameters analyzed were cross-sectional area, wrist-forearm index, entry-exit index, thinning range, palmar bowing of the flexor retinaculum, and vascularity/mobility. Current evidence allows us to affirm that ultrasound is useful in screening for CTS.

Nerve sonography in the diagnostic evaluation of primary and secondary carpal tunnel syndrome in rheumatoid arthritis.

BACKGROUND AND PURPOSE: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy and extra-articular manifestation of rheumatoid arthritis (RA). However, in patients with RA, it is not always possible to clinically distinguish an actual CTS from other RA-based complaints. METHODS: We evaluated the diagnostic role of nerve ultrasound (NUS) as supportive tool in the diagnostic process of CTS in patients with RA and tried to provide etiological clarification in cases of secondary CTS. Fifty-eight patients with RA and clinical suspicion of CTS were enrolled. All patients underwent a standardized clinical-neurological, electrophysiological (nerve conduction studies [NCS]), and NUS examination and completed the Boston CTS Questionnaire (BCTQ). RESULTS: In 96 of 116 hands examined, a clinical suspicion of CTS was documented. In 43 of 96 (44.8%) CTS-positive hands, the diagnosis was primarily confirmed by NCS, whereas in another 16 of 96 (30.2%) hands, the diagnosis could only be verified by NUS, leading to a diagnosis of CTS in 59 of 116 (50.8%) hands. In 19 of 59 (32.3%) CTS-positive hands, tenosynovial hypertrophy was observed, and in 7 of 59 (11.8%), a cystic mass was identified as the underlying cause of secondary CTS. A good correlation between NCS and NUS findings was documented, but no significant correlation was found between NCS, NUS, and clinical findings/BCTQ. CONCLUSIONS: In people with RA, a diagnosis of CTS purely on a clinical basis is nonspecific and should be supported by NCS and/or NUS. NUS markedly facilitates the diagnosis of CTS in these patients and enables differentiation between primary and secondary causes.

Transformer-Based Automated Segmentation of the Median Nerve in Ultrasound Videos of Wrist-to-Elbow Region.

Segmenting the median nerve is essential for identifying nerve entrapment syndromes, guiding surgical planning and interventions, and furthering understanding of nerve anatomy. This study aims to develop an automated tool that can assist clinicians in localizing and segmenting the median nerve from the wrist, mid-forearm, and elbow in ultrasound videos. This is the first fully automated single deep learning model for accurate segmentation of the median nerve from the wrist to the elbow in ultrasound videos, along with the computation of the cross-sectional area (CSA) of the nerve. The visual transformer architecture, which was originally proposed to detect and classify 41 classes in YouTube videos, was modified to predict the median nerve in every frame of ultrasound videos. This is achieved by modifying the bounding box sequence matching block of the visual transformer. The median nerve segmentation is a binary class prediction, and the entire bipartite matching sequence is eliminated, enabling a direct comparison of the prediction with expert annotation in a frame-by-frame fashion. Model training, validation, and testing were performed on a dataset comprising ultrasound videos collected from 100 subjects, which were partitioned into 80, ten, and ten subjects, respectively. The proposed model was compared with U-Net, U-Net++, Siam U-Net, Attention U-Net, LSTM U-Net, and Trans U-Net. The proposed transformer-based model effectively leveraged the temporal and spatial information present in ultrasound video frames and efficiently segmented the median nerve with an average dice similarity coefficient (DSC) of approximately 94% at the wrist and 84% in the entire forearm region.

One-Stop Automated Diagnostic System for Carpal Tunnel Syndrome in Ultrasound Images Using Deep Learning.

OBJECTIVE: Ultrasound (US) examination has unique advantages in diagnosing carpal tunnel syndrome (CTS), although identification of the median nerve (MN) and diagnosis of CTS depend heavily on the expertise of examiners. In the aim of alleviating this problem, we developed a one-stop automated CTS diagnosis system (OSA-CTSD) and evaluated its effectiveness as a computer-aided diagnostic tool. METHODS: We combined real-time MN delineation, accurate biometric measurements and explainable CTS diagnosis into a unified framework, called OSA-CTSD. We then collected a total of 32,301 static images from US videos of 90 normal wrists and 40 CTS wrists for evaluation using a simplified scanning protocol. RESULTS: The proposed model exhibited better segmentation and measurement performance than competing methods, with a Hausdorff distance (95th percentile) score of 7.21 px, average symmetric surface distance score of 2.64 px, Dice score of 85.78% and intersection over union score of 76.00%. In the reader study, it exhibited performance comparable to the average performance of experienced radiologists in classifying CTS and outperformed inexperienced radiologists in terms of classification metrics (e.g., accuracy score 3.59% higher and F1 score 5.85% higher). CONCLUSION: Diagnostic performance of the OSA-CTSD was promising, with the advantages of real-time delineation, automation and clinical interpretability. The application of such a tool not only reduces reliance on the expertise of examiners but also can help to promote future standardization of the CTS diagnostic process, benefiting both patients and radiologists.

Evaluation of ultrasound as diagnostic tool in patients with clinical features suggestive of carpal tunnel syndrome in comparison to nerve conduction studies: Study protocol for a diagnostic testing study.

BACKGROUND: Carpal Tunnel Syndrome (CTS) is the most common compressive neuropathy, accounting for 90% of all neuropathies. Its prevalence ranges from 3.8%-7.8% in the population. The gold standard for its diagnosis is the neurophysiological study (85% sensitivity and 95% specificity), with the disadvantage of being invasive, complex and expensive, which means an increase in cost and time for the diagnosis of the disease. The main objective of this diagnostic test evaluation study is to investigate the value of ultrasound in the diagnosis of CTS, and among the secondary objectives, to establish the ultrasound parameters that are predictors of CTS in comparison with neurophysiological studies, attempting to standardize a protocol and reference values that determine the presence or absence of CTS. METHODS: Prospective, cross-sectional study. The reference test with which we compared the ultrasound is the neurophysiological test (NPT). Patients will come consecutively from the Neurophysiology Department of the Virgen Macarena Hospital, with clinical suspicion of CTS and fulfilling the inclusion/exclusion criteria. To calculate the sample size (EPIDAT program) we proposed a sensitivity of 78% and specificity of 87% with a confidence level of 95%, requiring 438 patients (264 NPT positive, 174 NPT negative). We followed an ultrasound study protocol that included the ultrasound variables: cross-sectional area at the entrance and exit of the tunnel, range of nerve thinning, wrist-forearm index, flexor retinaculum bulging, power Doppler uptake and the existence of adjacent wrists or masses. We propose a timeline for the study to be performed between 2020 and 2023. Finally, we propose a cost-effectiveness analysis. DISCUSSION: Ultrasound not only allows to objectify the alterations of the median nerve but also the underlying pathological mechanisms in CTS. A multitude of ultrasound parameters have been described that should be regarded in syndrome's study, among which we included the cross-sectional area, the range of nerve thinning, the wrist-forearm index, flexor retinaculum bulging, power Doppler uptake and assessment of anatomical alterations. The use of ultrasound as a diagnostic tool in CTS has many advantages for both doctors and the patients, as it is a non-invasive, convenient, and fast tool increasingly accessible to professionals. TRIAL REGISTRATION: Trials registry number: NCT05556278.

The sono-elastography evaluation of the immediate effects of neurodynamic mobilization technique on median nerve stiffness in patients with carpal tunnel syndrome.

OBJECTIVES: The stiffness of median nerve increases in carpal tunnel syndrome (CTS) even at mild stage of syndrome which could be regarded as a diagnostic criterion. The aim of this study was to evaluate the immediate effects of neurodynamic technique on median nerve stiffness and cross-sectional area (CSA) at wrist and elbow in individuals with CTS. MATERIAL AND METHODS: It was a quasi-experimental study. Twenty patients were recruited for this study. They were included if aged 18-65 years and diagnosed with CTS based on electrodiagnostic and clinical findings. The exclusion criteria were previous surgeries at wrist or elbow. Patients were assessed by shear wave sono-elastography before and immediately after one session of neurodynamic mobilization technique (NDM). The primary outcome measure was the stiffness of the median nerve at wrist and the secondary outcomes were nerve stiffness at elbow and CSA of nerve at wrist and elbow. RESULTS: Median nerve stiffness and CSA decreased significantly at wrist immediately after a session of NDM. These parameters also decreased at elbow but were not statistically significant. CONCLUSION: One session of NDM reduced the stiffness and CSA of median nerve at wrist in patients with CTS as detected by sono-elastography verifying that sono-elastography is able to quickly detect the immediate biomechanical changes of the median nerve.

Effects of high-intensity laser therapy on pain, functional status, hand grip strength, and median nerve cross-sectional area by ultrasonography in patients with carpal tunnel syndrome.

The aim of this study was to evaluate the effects of high intensity laser therapy (HILT) on pain, functional status, hand grip strength, and median nerve cross-sectional area by ultrasonography in patients with carpal tunnel syndrome. Sixty patients who were diagnosed with carpal tunnel syndrome were included in the study. The patients observed during the research were randomly divided into two groups with 30 patients in each group. Splint+ exercise and HILT (pulsed mode with a power of 8.0 W and energy density of 8 J/cm2 for 1.40 minutes for every 25 cm2, continuous mode with a power of 3.0 W and energy density of 80 J/cm2 for 11 minutes for each 25 cm2; total 10 sessions 5 days a week) were applied for 2 weeks for the first group, and splint+exercise and sham laser treatment were applied for 2 weeks for the second group. Randomization was undertaken with the assistance of a computer-generated random number table before beginning the treatment processes. The patients were evaluated with the determined scales before the treatment, at the end of the treatment, and at the 3rd month. Hydraulic hand dynamometer was used to measure hand grip strength, visual analog scale (VAS) for pain, Boston CTS Questionnaire to assess function, and ultrasonography to measure median nerve cross-sectional area. The impact of time on the change in VAS levels was found to be of statistical significance within each group of patients (p<0.001), but between-group comparisons did not yield significant results (p<0.454). The effects of time on variations in Boston CTS Questionnaire scores were found to have been of statistical significance for both groups (p<0.001), but significance was not subsequently observed when the results of the two groups were compared on a between-group basis (p=0.226 and p=0.973 for the FSS and SSS, respectively). While time had a statistically significant effect on the change in hand grip strength for both groups (p=0.000), between-group comparisons statistical significance finding in favor of HILT was found in the early period (p=0.012). The time-group association patterns of the groups showed significant difference (p=0.025). While time had a statistically significant effect on the changes in the median cross-sectional areas of the nerve for the patients of both treatment groups (p<0.001), between-group comparisons yielded no findings of statistical significance (p=0.438). The time-group relationship patterns of the groups were found to reflect statistical significance (p=0.001). In conclusion, the results of the research presented here have confirmed that hand grip strength may increase and the median nerve's cross-sectional area may decrease upon the application of high-intensity laser for individuals experiencing CTS. However, this effect was demonstrated here only in the short-term and the evidence was not maintained through the course of follow-up of a longer duration.

Comparison of the Mean Cross-sectional Area of the Median Nerve between Pregnant and Non-Pregnant Women Using Ultrasonography in a Tertiary Level Hospital, Nepal.

Background The median nerve is subjected to compression in the carpal tunnel giving rise to a constellation of symptoms known as carpal tunnel syndrome. It is the most frequent form of peripheral entrapment neuropathies and is most prevalent in the middle age females. The most common cause of this syndrome is idiopathic. One of the known secondary causes is pregnancy. Objective To compare the mean cross sectional area of median nerve using ultrasound in pregnant and non-pregnant females at carpal tunnel inlet and its variations with different trimesters. Method The study was conducted during a period of one year (October 2014 to September 2015). A total of 204 participants were evaluated among which 102 were nonpregnant and 102 were pregnant. Among the 102 pregnant participants, 34 females each were in the first, second, and third trimesters. A convenience sampling technique was used for the selection of the participants. The mean cross-sectional area of the median nerve was calculated in both of these groups in both hands by using the direct method. The mean cross-sectional area of non-pregnant female was used as the reference value to which that of pregnant female were compared. Data obtained were compiled and analyzed using Statistical Package for Social Sciences Version 16. Result The overall mean cross-sectional area of the median nerve in non-pregnant females was 6.76 ± 1.05 mm2 and in pregnant females was 6.84 ± 1.09 mm. No statistically significant difference was noted in the mean cross-sectional area of the median nerve in either hand in both pregnant and non-pregnant females. No statistically significant difference was noted in the overall mean cross-sectional area between the non-pregnant and pregnant females. There was no significant difference in the mean cross-sectional area within the different trimesters in both hands on intergroup comparisons. Conclusion Ultrasound examination of the median nerve and measurement of its crosssectional area is a useful diagnostic tool in the evaluation of carpal tunnel syndrome. Ultrasound has the advantage of easy availability, low cost, quick scan time, able to scan a long segment of nerve and examine the structures in both static and dynamic states. Besides, it also helps in the identification of various anatomic variants and pathologies within or adjacent to carpal tunnel.

Diagnostic utility of anteroposterior measurements of the median nerve on sagittal ultrasonographic images and their correlation with clinical findings in carpal tunnel syndrome.

PURPOSE: To investigate the efficacy of sagittal ultrasonography of the median nerve in diagnosing carpal tunnel syndrome (CTS). METHODS: Seventy-six hands with idiopathic CTS and 80 hands of asymptomatic subjects were included. All patients with CTS underwent ultrasonographic examination, electrodiagnostic testing, and CTS-6 assessment. In the sagittal ultrasonographic examination, the maximum and minimum median nerve diameters (MNDs) were measured at the proximal and distal ends of the carpal tunnel, respectively. The median nerve stenosis rate (MNSR) was computed as (1 - minimum MND/maximum MND) × 100 (%). The cross-sectional area (CSA) of the median nerve at the level of the pisiform was measured. RESULTS: In the sagittal ultrasonographic examination, the mean maximum MNDs were 0.252 cm and 0.202 cm, mean minimum MNDs were 0.145 cm and 0.165 cm, and mean MNSRs were 41.83% and 17.35% in the CTS and control groups, respectively; the mean maximum MND and MNSR were considerably larger in the CTS group. The maximum MND and MNSR were correlated with the electrodiagnostic testing results and CTS-6 score. The MNSR with a cut-off value of 34.0% had a higher sensitivity and specificity than the CSA in diagnosing CTS. CONCLUSIONS: Sagittal ultrasonographic examination is useful in diagnosing CTS.