多灶性运动神经病周围神经超声特征

目的 观察多灶性运动神经病（MMN）患者周围神经的超声特征。方法 纳入8例MMN患者（MMN组）及18名健康志愿者（对照组）,观察MMN超声特征,并与肌电图诊断结果对比,比较组间周围神经横截面积（CSA）的差异。结果 超声与肌电图共检查8例MMN患者的96条周围神经,诊断周围神经异常率分别为32.29%（31/96）及31.25%（30/96）,均以正中神经（68.75% vs 56.25%）及尺神经（50.00% vs 56.25%）异常为主。超声及肌电图对其中73条（73/96,76.04%）的诊断结果一致,超声表现包括神经增粗、回声减低、束状结构消失及外膜回声增强。MMN组双侧正中神经、双侧尺神经及左侧腓总神经CSA明显大于对照组（P均<0.05）,其余神经CSA组间差异均无统计学意义（P均>0.05）。结论 MMN超声异常多见于上肢正中神经及尺神经,与肌电图检查结果结合可为临床诊断MMN提供更多信息。     

超声诊断糖尿病周围神经病变

目的 探讨超声在糖尿病周围神经病变(DPN)诊断中的应用价值。方法 收集我院DPN患者40例(DPN组),选取正常对照30名(正常对照组),观察两组坐骨神经、腓总神经、胫神经的连续性和神经内部回声,测量并比较两组神经的前后径(D₁)和横径(D₂),并计算横截面积(CSA)。结果 正常对照组神经纵断面声像图呈束条状高或中等回声,内含多数平行、被高回声分开断续的线状低回声;横断面呈圆形、卵圆形高回声,其内分布细点状低回声。DPN组表现为受累神经肿大、增粗,内部回声减低,神经内平行线状结构消失。DPN组坐骨神经、腓总神经、胫神经的D₁、D₂、CSA均较正常对照组明显增加,差异均有统计学意义(P均<0.01)。结论 超声能够清晰显示DPN患者受累神经结构、位置以及病变范围,对DPN有较高的诊断价值,并可指导临床选择治疗和手术方案。     

Peripheral Nerve Ultrasound in Small Fiber Polyneuropathy

Routine nerve conduction studies are normal in patients with small fiber neuropathy (SFN), and a definitive diagnosis is based on skin biopsy revealing reduced intra-epidermal nerve fiber density (IENFD). In large fiber polyneuropathy, ultrasound (US) parameters indicate enlargement in cross-sectional area (CSA). This study was aimed at determining if similar changes in large fibers on US are apparent in patients with SFN. Twenty-five patients with SFN diagnosed by reduced IENFD and 25 age- and body mass index (BMI)-matched healthy controls underwent US studies of sural and superficial peroneal sensory nerves. The mean CSA of the sural nerve in SFN patients was 3.2 ± 0.8 mm², and in controls, 2.7 ± 0.6 mm² (p < 0.0070), and this was independent of sex. There was no difference in the thickness-to-width ratio or echogenicity of the nerves. US of the sural nerve in patients diagnosed with small fiber neuropathy reveals an enlarged cross-sectional area similar to that in large fiber polyneuropathy.     

Neuromuscular sonography detects changes in muscle echotexture and nerve diameter in ICU patients within 24 h

PurposeDuring an ICU stay, changes in muscles and nerves occur that is accessible via neuromuscular sonography.Methods17 patients recruited from the neurological and neurosurgical ICU (six women; 66 ± 3 years) and 7 healthy controls (three women, 75 ± 3 years) were included. Muscle sonography (rectus abdominis, biceps, rectus femoris and tibialis anterior muscles) using gray-scale values (GSVs), and nerve ultrasound (peroneal, tibial and sural nerves) analyzing the cross-sectional area (CSA) were performed on days 1 (t1), 3 (t2), 5 (t3), 8 (t4), and 16 (t5) after admission.ResultsTime course analysis revealed that GSVs were significantly higher within the patient group for all of the investigated muscles (rectus abdominis: F = 7.536; p = 0.011; biceps: F = 14.761; p = 0.001; rectus femoris: F = 9.455; p = 0.005; tibialis anterior: F = 7.282; p = 0.012). The higher GSVs were already visible at t1 or, at the latest, at t2 (tibialis anterior muscles). CSA was enlarged in all of the investigated nerves in the patient group (peroneal nerve: F = 7.129; p = 0.014; tibial nerve: F = 28.976, p < 0.001; sural nerve: F = 13.051; p = 0.001). The changes were visible very early (tibial nerve: t1; peroneal nerve: t2). The CSA of the motor nerves showed an association with the ventilation time and days within the ICU (t1 through t4; p < 0.05).DiscussionWe detected very early changes in the muscles and nerves of ICU-patients. Nerve CSA might be a useful parameter to identify patients who are at risk for difficult weaning. Therefore our observations might be severity signs of neuromuscular suffering for the most severe patients.     

High resolution ultrasound in subclinical diabetic neuropathy: A potential screening tool

IntroductionDetection of subclinical neuropathy can aid in triage, timely intervention and dedicated care to reduce disease progression and morbidity. High resolution sonography has emerged as a promising technique for evaluation of peripheral nerves. The aim of the present study was to assess the utility of high resolution sonography in screening diabetic patients for subclinical neuropathy.MethodsA total of 70 adult patients with type 2 diabetes mellitus and 30 controls were enrolled; those with clinical features of neuropathy constituted the diabetic polyneuropathy group and those without symptoms/normal nerve conduction the non-diabetic polyneuropathy group. After institutional ethical committee approval and informed consent, high resolution sonography was performed by two musculoskeletal radiologists. Nerves studied were median (elbow and wrist), ulnar (cubital tunnel and Guyon’s canal), common peroneal (fibular head) and posterior tibial nerve (medial malleolus).The size (cross sectional area), shape, echogenicity and morphology of nerve were assessed and compared between the groups.ResultsThe mean cross sectional area of all nerves was significantly higher both in diabetic polyneuropathy and non-diabetic polyneuropathy group compared to controls (p value < .001). Common peroneal nerve cross sectional area of 4.5 mm² had the highest sensitivity (93%) and specificity (86%) for detecting nerve changes in the non-diabetic polyneuropathy group. The nerves were more rounded, hypoechoic and had an altered morphology in both study groups.ConclusionPresence of sonographic nerve changes in asymptomatic diabetics depicted that morphological alterations in nerves precede clinical symptoms. High resolution sonography detected nerve changes with a good accuracy, and thus, can be a potential screening tool for detection of subclinical diabetic polyneuropathy.     

Ultrasonography of peripheral nerves.

With recent improvements in ultrasound (US) imaging equipment and refinements in scanning technique, an increasing number of peripheral nerves and related pathologic conditions can be identified. US imaging can support clinical and electrophysiologic testing for detection of nerve abnormalities caused by trauma, tumors, and a variety of nonneoplastic conditions, including entrapment neuropathies. This article addresses the normal US appearance of peripheral nerves and discusses the potential role of US nerve imaging in specific clinical settings. A series of US images of diverse pathologic processes involving peripheral nerves is presented.     

Physiological Localization by Sensory and Motor Inching Studies and Structural Abnormalities Detected by Ultrasonographic Changes in Carpal Tunnel Syndrome

ObjectiveTo study mild to moderate carpal tunnel syndrome (CTS), compare median nerve entrapment sites detected by electrophysiological inching studies with ultrasonographic abnormalities of cross-sectional area (CSA), and correlate focal points of conduction delays detected by sensory and motor inching recorded from the third digit and second lumbrical muscle.DesignAnalytic cross-sectional study.SettingDepartment of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital, Bangkok, Thailand.ParticipantsHands from 10 participants without CTS (n=15) and hands with mild to moderate CTS from 29 participants (n=40) were selected by convenience sampling (N=55).InterventionsNot applicable.Main Outcome MeasuresCorrelation of electrophysiological entrapment site localization by inching study with anatomic entrapment site detected by ultrasound (US).ResultsIn all 40 hands tested, a sharply localized latency was found to increase across a 1-cm segment, most commonly 2-3 cm distal to the distal wrist crease for both sensory and motor studies, showing a good match between the 2 with Pearson correlation coefficient value (r=0.72). US revealed a narrowing CSA of the median nerve at 1-2 cm distal to the distal wrist crease.ConclusionsThis study showed a high correlation for focal point conduction delay detected by sensory and motor nerve conduction study. Recording from the second lumbricalis facilitated motor inching along the straight course of the nerve instead of the arcuate recurrent branch innervating the abductor pollicis brevis, the muscle traditionally used. US examination also revealed a localized narrowing of the median nerve CSA at 1-2 cm distal to the distal wrist crease, a possible site for anatomic entrapment. The most enlarged CSA was seen at the distal wrist crease, a level corresponding to the inlet of the carpal tunnel.     

胰腺实性假乳头状瘤的超声及超声造影表现

目的 探讨胰腺实性假乳头状瘤的超声及超声造影表现.方法 分析20例经手术病理证实的胰腺实性假乳头状瘤的超声表现,对其中4例的超声造影表现进行探讨.结果 胰腺实性假乳头状瘤多发生于年轻女性.肿瘤体积较大,边界清晰,多数有包膜.病变呈囊实混合或呈实性肿块.少数病例可见较粗大钙化.肿瘤可发生于胰腺的任何部位,但以胰头多见.4例造影病例于动脉相肿物边缘均可见包膜样环状等增强.其中3例动脉相肿瘤内部呈不均匀低增强伴无增强区,静脉相造影剂消退呈明显低增强;1例动脉相肿瘤内部无明显增强,病理示肿瘤组织绝大部分坏死.结论 胰腺实性假乳头状瘤有其特征性的超声和超声造影表现,超声造影能更准确地反映其组织学特征.     

IVU后CT扫描对小儿先天输尿管畸形的诊断价值

目的探讨IVU/CT诊断小儿先天输尿管畸形的价值.方法 49例疑诊输尿管畸形患儿,行头低位腹部无加压静脉尿路造影,造影后20 min行CT扫描,观察IVU和IVU/CT显示肾脏、尿路及输尿管病变,并与手术结果对照.结果①16侧肾脏IVU不显影,IVU/CT示重度肾积水,其中UPJ 8侧,UVJ 4侧,发育不良重肾2侧,膀胱输尿管返流2侧;②IVU/CT 39侧积水肾实质密度(130.5±29.8) Hu,正常肾实质密度(82.4±19.0) Hu,二者存在显著差异 (P<0.05);③IVU、IVU/CT对39例UPJ、15例UVJ和15例重复肾输尿管畸形的诊断符合率分别为78.8%和 97.0% (P>0.05)、53.3%和100%(P<0.05)、40.0%和93.3% (P<0.001).结论 IVU/CT相当于肾脏CT增强延迟扫描,可不依赖肾功能丧失程度显示输尿管畸形;IVU/CT对输尿管末端梗阻和重复肾输尿管畸形的诊断具有重要价值.     

Inter-Rater,Intra-Rater,and Inter-Machine Reliability of Quantitative Ultrasound Measurements of the Patellar Tendon

The use of ultrasound (US) to perform quantitative measurements of musculoskeletal tissues requires accurate and reliable measurements between investigators and ultrasound machines. The objective of this study was to evaluate inter-rater and intra-rater reliability of patellar tendon measurements between providers with different levels of US experience and inter-machine reliability of US machines. Sixteen subjects without a history of knee pain were evaluated with US examinations of the patellar tendon. Each tendon was scanned independently by two investigators using two different ultrasound machines. Tendon length and cross-sectional area (CSA) were obtained, and examiners were blinded to each other's results. Tendon length was measured using a validated system involving surface markers and calipers, and CSA was measured using each machine's measuring software. Intra-class correlation coefficients (ICCs) were used to determine reliability of measurements between observers, where ICC > 0.75 was considered good and ICC > 0.9 was considered excellent. Inter-rater reliability between sonographers was excellent and revealed an ICC of 0.90 to 0.92 for patellar tendon CSA and an ICC of 0.96 for tendon length. ICC for intra-rater reliability of tendon CSA was also generally excellent, with ICC between 0.87 and 0.96. Inter-machine reliability was excellent, with ICC of 0.91–0.98 for tendon CSA and 0.96–0.98 for tendon length. Bland–Altman plots were constructed to measure validity and demonstrated a mean difference between sonographers of 0.03 mm² for CSA measurements and 0.2 mm for tendon length. Using well-defined scanning protocols, a novice and an experienced musculoskeletal sonographer attained high levels of inter-rater agreement, with similarly excellent results for intra-rater and inter-machine reliability. To our knowledge, this study is the first to report inter-machine reliability in the setting of quantitative musculoskeletal ultrasound.     

Effects of Local Warming on the Peripheral Vein Cross-Sectional Area in Children Under Sedation

PurposePeripheral venous catheterization is challenging in small children. The local warming technique has been used to increase the peripheral vein cross-sectional area (CSA) and improve the success rate. However, there is limited evidence on the effect of local warming on venous CSA in children under sedation.DesignA pilot randomized controlled trial.MethodsEligible children aged 1 to 4 years undergoing ambulatory surgery were enrolled. At the bedside in the ambulatory surgery center, they were routinely sedated with 1 mcg/kg of intranasal dexmedetomidine. Through a computer allocation program, children were randomized into either a control group or a local warming group. Cephalic vein and basilic vein at 1 cm proximal to cubital fossa were scanned with ultrasound to measure venous CSA. Children in the control group received no intervention; those in the local warming group had a prepared hot pack of ~40°C applied to the target area on the arm for 5 minutes. A second ultrasound measurement was undertaken in both groups.FindingsA total of 35 from 40 children were analyzed. Cephalic vein CSA and basilic vein CSA increased significantly vs the first measurement within the local warming group (P < .05 for both) but not in the control group (P > .05 for both). Cephalic vein CSA was significantly different between groups at the second measurement (P < .05) but not at the first measurement (P > .05). Basilic vein CSA was significantly different between groups neither at the first measurement nor at the second measurement (P > .05 for both). The application of local warming resulted in an average of 34% increase (from 4.1 to 5.5 mm²) in cephalic vein CSA and an average of 21% increase (from 4.8 to 5.8 mm²) in basilic vein CSA.ConclusionsThe application of local warming induced mild venodilation in cephalic vein with an increase in CSA by 34% and had little venodilation effect on the basilic vein with an increase in CSA by only 21%.     

Ultrasound Parameters Other Than the Direct Measurement of Ulnar Nerve Size for Diagnosing Cubital Tunnel Syndrome: A Systemic Review and Meta-analysis

ObjectiveTo investigate the diagnostic performance of available ultrasound (US) parameters, other than the direct measurements of ulnar nerve size, that is, cross-sectional area (CSA) and diameter, for diagnosing cubital tunnel syndrome (CuTS).Data SourcesDatabases, including PubMed and Embase, were searched from the earliest record of CuTS US to April 24, 2018.Study SelectionPublished studies (N=13) comparing US parameters of ulnar nerves between patients with CuTS and patients without CuTS were included.Data ExtractionStudy design, participants’ demographics, diagnostic references of CuTS, and US parameters other than the direct measurements of the ulnar nerve size were retrieved from the included studies.Data SynthesisThis systematic review comprised 663 CuTS patients and 543 patients without CuTS. The pooled nerve swelling ratio in the CuTS group was significantly larger than that of the controls. The mean between-group differences of CSA_{Max or ME}/CSA_arm, CSA_{Max or ME}/CSA_forearm and CSA_{Max or ME}/CSA_wrist were 1.03 (95% confidence interval [CI], 0.77-1.29), 1.38 (95% CI, 0.93-1.82), and 0.83 (95% CI, 0.56-1.11), respectively. Regarding the swelling ratio of CSA_{Max or ME} /CSA_arm, the pooled sensitivity and specificity available from the 3 included studies were 0.67 (95% CI, 0.59-0.74) and 0.81 (95% CI, 0.75-0.86), respectively. Similarly, for the swelling ratio of CSA_{Max or ME}/CSA_forearm, the pooled sensitivity and specificity were 0.62 (95% CI, 0.54-0.69) and 0.86 (95% CI, 0.81-0.90), respectively. Other US parameters identified in this review included nerve-flattening ratio (maximum diameter/minimum diameter), nerve-to-tunnel ratio (ulnar nerve CSA/cubital tunnel CSA), nerve echogenicity, and intraneural vascularity, all of which were reported in a minority of included articles.ConclusionsDespite the insufficient number of pertinent studies to prove its superiority to other US measurements, the ulnar nerve-swelling ratio can be a complementary tool for diagnosing CuTS. The presence of intraneural vascularity, increased flattening ratio, and enlarged intraneural hypoechoic fraction also seem to be potential US indicators for CuTS diagnosis, which need to be validated with more prospective studies.     

Sonographic measurement of the normal suprascapular nerve and omohyoid muscle

The aim of this study was to obtain normative ultrasonography (US) data on the suprascapular nerve (SSN) and omohyoid muscle (OM) in the lateral cervical region. The SSN and OM are known to be related throughout the nerve's course, yet little imaging data exists on these structures at areas more proximal than the suprascapular foramen. US data from a convenience sample of 33 asymptomatic subjects between 21 and 42 years of age were collected. Cross sectional area (CSA) of the SSN, distances from the OM to the SSN, and long-axis diameter of the OM at three reference points were obtained. The mean CSA of the SSN at both its origin and over the first rib was 1.9 mm² and at the distal clavicle was 2.0 mm². The mean distance of the OM to the SSN at these locations was 7.6 mm, 4.2 mm and 2.8 mm respectively. The mean long axis diameter of the OM was 2.4 mm at the SSN origin, 3.4 mm at the first rib, and 4.1 mm at the distal clavicle. We present US data from asymptomatic subjects on the SSN and OM. Our results show that the SSN nerve CSA is consistent throughout the nerves proximal course. Furthermore, the OM and SSN tend to approximate as they course distally. Future studies with larger samples will better characterize the normal sonoanatomy of these structures between genders and across different ages.     

Structural abnormalities of the trigeminal root revealed by diffusion tensor imaging in patients with trigeminal neuralgia caused by neurovascular compression: a prospective, double-blind, controlled study

Because diffusion tensor imaging (DTI) is able to assess tissue integrity, we used diffusion to detect abnormalities in trigeminal nerves (TGN) in patients with trigeminal neuralgia (TN) caused by neurovascular compression (NVC). We also studied anatomical TGN parameters (cross-sectional area [CSA] and volume [V]). Using DTI sequencing in a 3-T magnetic resonance imaging (MRI) scanner, we measured the fraction of anisotropy (FA) and the apparent diffusion coefficient (ADC) of TGN in 10 patients selected as candidates to have microvascular decompression (MVD) for TN, and 6 normal control subjects. We compared data between the affected nerves of TN (ipsilateral TN), unaffected nerves of TN (contralateral TN), and both nerves in normal subjects (controls), and correlated these data with CSA and V. The FA of the ipsilateral TN (0.37 ± 0.08) was significantly lower (P < .05) compared with the contralateral TN (0.48 ± 0.08) and control values (0.52 ± 0.04). The ADC of ipsilateral TN (5.6 ± 0.89 mm²/s) was significantly higher (P < .05) compared with the contralateral TN (4.26 ± 0.59 mm²/s) and control values (3.84 ± 0.43 mm²/s). Ipsilateral TN had less V and CSA compared with contralateral TN and control values (P < .05). The Spearman correlation coefficient showed a strong positive correlation between loss of FA and loss of V (r = 0.7576) and loss of CSA (r = 0.9273) of affected nerves. The Spearman correlation coefficient showed a strong negative correlation between increase in ADC and loss of V (r = −0.7173) and loss of CSA (r = −0.7416) in affected nerves. DTI revealed alteration in the FA and ADC values of the affected TGN. These alterations were correlated with atrophic changes in patients with TN caused by NVC.     

The value of sonographic quantitative parameters in the diagnosis of carpal tunnel syndrome in the Vietnamese population

ObjectiveTo examine the value of ultrasound (US) in the diagnosis of carpal tunnel syndrome (CTS) in the Vietnamese population.MethodsThis prospective cross-sectional study involved 42 wrists of 25 patients with idiopathic CTS evaluated by US. In addition, 38 wrists of 22 healthy volunteers were included as the control group.ResultsSignificant differences in the median nerve cross-sectional area (CSA) at different levels were found between patients with CTS and controls. Using a cut-off value of 9.5 mm² for the median nerve CSA at the pisiform (p-CSA), US had a sensitivity and specificity of 95.2% and 97.4%, respectively, for the diagnosis of CTS. Area under the curve analysis revealed a sensitivity and specificity of 100% and 95.4%, respectively, for the prediction of severe CTS using a p-CSA of >15.5 mm².ConclusionsThe median nerve CSA is a highly accurate parameter in the diagnosis of CTS. We recommend using a p-CSA of >9.5 mm² as a diagnostic criterion for CTS and a p-CSA of >15.5 mm² as a marker for severe CTS in the Vietnamese population.Research Registry number: 7261     

B-Mode Ultrasonography Is a Reliable and Valid Alternative to Magnetic Resonance Imaging for Measuring Patellar Tendon Cross-Sectional Area

This study investigated the validity and reliability of measuring patellar tendon (PT) cross-sectional area (CSA) using magnetic resonance imaging (MRI) and ultrasound (US) imaging. Nineteen healthy participants (10 women, 9 men) participated in three imaging sessions of the PT, once via MRI and twice via US, with image acquisition conducted by two raters, one experienced (rater 2) and one inexperienced (rater 1). All PT segmentations were analyzed by both raters. The validity of US-derived estimates of PT CSA against MRI estimates was analyzed using linear regression. Within-day reliability of US and MRI measurements and between-day reliability of US measurements were quantified using typical error (TE) and intra-class correlation coefficients (ICC_3,1). There was good agreement between US- and MRI-derived estimations of PT CSA (standard errors of the estimate of 3.3 mm² for rater 1 and 2.6 mm² for rater 2; Pearson's r = 0.97 and 0.98 for raters 1 and 2, respectively). Within-session reliability for estimations of total PT CSA from US and MRI were excellent (ICC_3,1 >0.95, coefficient of variation [CV] <4.1%, TE = 1.3–3.6 mm². Between-day reliability for US was excellent (ICC_3,1 >0.97, CV <2.7%, TE = 1.6–2.3 mm²), with little difference between raters. These findings suggest that MRI and US both provide reliable estimates of PT CSA and that US can provide a valid measure of PT CSA.     

Tai Chi with mental imagery theory improves soleus H-reflex and nerve conduction velocity in patients with type 2 diabetes

ObjectivesDiabetes is a disease that leads to damage to the peripheral nerves which may eventually cause balance instability. The purpose of this study was to determine the effect of 8 weeks of Tai Chi (TC) training combined with mental imagery (MI) on soleus H-reflex and nerve conduction velocity (NCV) of the sural and superficial peroneal nerves in people with diabetes.DesignsQuasi-experimental, one group pretest-posttest design.SettingHuman Research Laboratory.InterventionsA series of Yang style of Tai Chi classes with mental imagery, one hour, two sessions per week for 8 weeks was done.Main outcome measuresThe Activities-specific Balance Confidence (ABC) Scale, Functional Reach Test (FRT), and One Leg Standing Test (OLS) were measured as functional data. Hoffman reflex (H-reflex), and sural and superficial peroneal NCV were measured as main outcomes.ResultsAll functional outcomes measures were significantly improved after the intervention (p < 0.01). In the H-reflex, there was a significant increase in amplitude (μV) after completing 8 weeks of TC exercise (p = 0.02). In the sural nerve, the velocity (p = 0.01), amplitude (p = 0.01), and latency (p = 0.01) were significantly improved between pre and post-test. In the superficial peroneal nerve, significant improvements were observed in (p = 0.02) and latency (p = 0.01), but not in amplitude (μV) (p > 0.05).ConclusionsCombining TC intervention with MI theory showed an improvement in the H-reflex and NCV tests, which suggests improved balance and walking stability.     

Can Ultrasound of the Tibial Nerve Detect Diabetic Peripheral Neuropathy?: A cross-sectional study

OBJECTIVE

Peripheral nerve imaging by portable ultrasound (US) may serve as a noninvasive and lower-cost alternative to nerve conduction studies (NCS) for diagnosis and staging of diabetic sensorimotor polyneuropathy (DSP). We aimed to examine the association between the size of the posterior tibial nerve (PTN) and the presence and severity of DSP.

RESEARCH DESIGN AND METHODS

We performed a cross-sectional study of 98 consecutive diabetic patients classified by NCS as subjects with DSP or control subjects. Severity was determined using the Toronto Clinical Neuropathy Score. A masked expert sonographer measured the cross-sectional area (CSA) of the PTN at 1, 3, and 5 cm proximal to the medial malleolus.

RESULTS

Fifty-five patients had DSP. The mean CSA of the PTN in DSP compared with control subjects at distances of 1 (23.03 vs. 17.72 mm²; P = 0.004), 3 (22.59 vs. 17.69 mm²; P < 0.0001), and 5 cm (22.05 vs. 17.25 mm²; P = 0.0005) proximal to the medial malleolus was significantly larger. Although the area under the curve (AUC) for CSA measurements at all three anatomical levels was similar, the CSA measured at 3 cm above the medial malleolus had an optimal threshold value for identification of DSP (19.01 mm²) with a sensitivity of 0.69 and a specificity of 0.77 by AUC analysis.

CONCLUSIONS

This large study of diabetic patients confirms that the CSA of the PTN is larger in patients with DSP than in control subjects, and US is a promising point-of-care screening tool for DSP.Ultrasound (US) for nerve imaging is increasingly used by various medical specialties for both diagnostic and therapeutic purposes (1,2). Modern US machines permit real-time, point-of-care imaging of nerves and their surrounding structures with high fidelity and without patient discomfort or radiation exposure. One promising application of US technology of interest to internists, anesthesiologists, and surgeons may be its ability to rapidly and reliably identify peripheral neuropathy, which traditionally requires resource-intensive nerve conduction studies (NCS) for formal diagnosis (3,4). Preliminary data signal a direct relationship that is independent of BMI, age, height, or weight between the presence of diabetic neuropathy and a greater cross-sectional area (CSA) of peripheral nerves as visualized by US (5,6). However, these previously published studies are limited by small sample sizes and cannot offer predictive values for US as a diagnostic test (6–8). In this larger observational study, we aimed to determine whether US can reliably detect the presence and severity of diabetic sensorimotor polyneuropathy (DSP). We hypothesized that the CSA of the posterior tibial nerve (PTN) as measured by US is higher in diabetic patients with DSP compared with diabetic patients without DSP.     

Penetrating injuries to the nerves of the lower extremity: principles of diagnosis and treatment

Background. Lower extremity nerve injuries caused by wounds are often not noticed immediately after trauma. The purpose of this article was to analyze the localization of penetrating injuries to the nerves, the mechanism and extent of the lesions, and the microsurgical techniques used. The diagnostic and therapeutic basics in penetrating injuries of lower extremity nerves are also described. Material and methods. The clinical material consisted of 67 patients treated surgically for penetrating injuries of lower extremity nerves. Results. In our material we observed penetrating injuries to the common peroneal nerve (41 cases), tibial nerve (9 cases), sciatic nerve (6 cases), combined common peroneal and tibial nerves (8 cases), and miscellaneous (foot injuries, 3 cases). The mechanism of injury included 51 cases of neurotmesis (primary injuries) and 16 cases of nerve compression (secondary injuries). In 5 cases, lesions of the major vessels and common peroneal and tibial nerves were observed. Conclusions. Penetrating injuries to the common peroneal nerve are the most frequent lesions of the peripheral nervous system within the lower limbs. The early detailed inspection of wounds, especially those localized in areas posing a particular threat to peripheral nerves, is an essential part of surgical treatment.     

Sural nerve conduction studies and late responses in children undergoing hemodialysis

Physiologic evidence of peripheral neuropathy has been described previously in children undergoing hemodialysis. In order to detect early or subclinical evidence of peripheral neuropathy, several newer electrophysiologic techniques, including latencies of late responses (H reflex and F response) and sural nerve sensory studies, were evaluated in addition to routine motor and sensory conduction in 17 randomly selected children (mean age 14.2 years) undergoing hemodialysis (12 of whom had no clinical evidence of peripheral neuropathy) and 20 age-matched normal control subjects. Conventional motor and sensory conduction studies of median and ulnar nerves and motor conduction of peroneal and tibial nerves showed abnormalities of motor conduction in 5 (29%) and abnormalities of sensory conduction in 2 (12%). Sural nerve sensory potentials were abnormal in 10 (59%) patients. Late response were significantly abnormal in 10 (59%) patients, 5 (29%) of whom had normal routine motor conduction studies in the same nerve distribution. The abnormalities of late responses and motor and sensory conduction were more evident in lower limbs. Studies of late responses and sural sensory conduction provide a method of detecting subclinical neuropathy in this patient population at a time when results of conventional motor and sensory conduction tests are within normal limits. Effects of dialysis may then be followed quantitatively in patients whose neuropathy would otherwise be undetectable.