Jun-Sik Yoon

INTRODUCTION: The aims of this study were to identify factors affecting the measurement of nerve cross-sectional area (CSA) and to establish normal reference values for nerve ultrasonography of the upper extremity. METHODS: Ninety-seven age-matched, healthy individuals were enrolled. Ultrasonographic tests were performed by tracing nerves from the axilla to the distal arm. CSA was measured at the following locations: median nerve (carpal tunnel inlet, forearm, antecubital fossa, midhumerus); uln

High-resolution ultrasound can demonstrate focal nerve enlargement in entrapment neuropathies. We hypothesized that a ratio between the nerve cross-sectional area at the site of maximal enlargement and at an unaffected site may improve diagnostic accuracy in ulnar neuropathy at the elbow (UNE), when compared to a single measurement at the site of maximal enlargement. Ultrasound was used to measure the cross-sectional area of the ulnar nerve at three sites in 30 normal, healthy controls and 26 in

Although it entails a radiation hazard risk, the use of fluoroscopy during caudal epidural steroid injection has increased to help place the medication more accurately and allowed physicians to maximize the procedure's therapeutic success rate. To investigate the feasibility of using real-time high resolution ultrasonography for guiding the epidural needle into the caudal epidural space and to confirm any vascular intake of medication, we performed color Doppler ultrasonography while medication

INTRODUCTION: The aim of this study was to determine normal reference values for cross-sectional area (CSA) and the correlation between demographic factors and CSA in the cervical roots and brachial plexus trunks using ultrasonography. METHODS: Ninety-five age-matched healthy individuals were studied. Ultrasonographic tests were performed via nerve tracing from the cervical root to the brachial plexus trunk. The CSA of each nerve was measured in the C5-8 ventral roots and brachial plexus (trunk

INTRODUCTION: The aim of this study was to improve our understanding of the pathophysiology of carpal tunnel syndrome (CTS) and to highlight the ultrasonographic cross-sectional area (CSA) ratio as a tool for assessing outcomes by investigating postoperative changes. METHODS: Twenty-four individuals with CTS were evaluated using the Boston questionnaire, nerve conduction studies, and ultrasound, preoperatively and at 3 weeks and 3 months postoperatively. RESULTS: Improved symptom scores, decreas

The cubital tunnel is the most common site of ulnar nerve entrapment. Previous ultrasound studies have demonstrated enlargement of the ulnar nerve in cubital tunnel syndrome but did not report on the cubital tunnel itself. Twenty-two individuals with cubital tunnel syndrome were evaluated with nerve conduction studies and ultrasound. The ultrasound measurement that most strongly correlated with conduction velocity was the ratio of ulnar nerve to cubital tunnel cross-sectional area with the elbow

OBJECTIVE: Ultrasound-guided cervical nerve root block (US-CRB) is considered a safe and effective method for the treatment of radicular pain. However, previous studies on the spreading pattern of injected solution in US-CRB have reported conflicting results. The aim of this study was to investigate the spreading pattern in relation to injection volume. DESIGN: An institutional, prospective case series. SETTING: A university hospital. SUBJECTS: Fifty-three patients diagnosed with mono-radiculopa

OBJECTIVES: The aim of this study was to measure the degree of movement of the ulnar nerve in the cubital tunnel using sonography in patients with ulnar neuropathy at the elbow compared to a healthy control group. METHODS: We examined the ulnar nerve in the cubital tunnel using sonography with the elbow extended and then flexed in 26 patients with ulnar neuropathy and 13 control participants. The distance from the ulnar nerve to the skin, medial epicondyle, and tip of olecranon at the inlet of t

BACKGROUND: In case of focal neuropathy, the muscle fibers innervated by the corresponding nerves are replaced with fat or fibrous tissue due to denervation, which results in increased echo intensity (EI) on ultrasonography. EI analysis can be conducted quantitatively using gray scale analysis. Mean value of pixel brightness of muscle image defined as EI. However, the accuracy achieved by using this parameter alone to differentiate between normal and abnormal muscles is limited. Recently, attemp

INTRODUCTION: Ulnar nerve displacement at the elbow causes overestimation of nerve conduction velocity. We hypothesized that this overestimation may cause false-negative results when the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM) diagnostic criteria are used. METHODS: We investigated 9 cases of ulnar neuropathy at the elbow, all having ulnar nerve displacement confirmed by ultrasonography and meeting none or just one of the AANEM criteria with distance measureme

This study shows that transverse median nerve movements decreased during grip using US and correlated negatively with CTS severity. Muscle Nerve, 2016 Muscle Nerve 54: -, 2016 Muscle Nerve 54: 738-742, 2016.

INTRODUCTION: The purpose of this study was to investigate the usefulness of the echogenicity (EI) ratio of the thenar to hypothenar muscle measured using ultrasonography in assessing the severity of carpal tunnel syndrome (CTS). METHODS: Fifty-nine hands of 30 patients electrodiagnostically confirmed as having CTS were classified into 3 subgroups (mild, moderate, and severe). The EI of the thenar and hypothenar muscles was measured with ultrasonography, and the EI ratio was calculated in the pa