Thoracic outlet syndrome in 3T MR neurography-fibrous bands causing discernible lesions of the lower brachial plexus.

OBJECTIVES: To investigate whether targeted magnetic resonance neurography (MRN) of the brachial plexus can visualise fibrous bands compressing the brachial plexus and directly detect injury in plexus nerve fascicles. METHODS: High-resolution MRN was employed in 30 patients with clinical suspicion of either true neurogenic thoracic outlet syndrome (TOS) or non-specific TOS. The protocol for the brachial plexus included a SPACE (3D turbo spin echo with variable flip angle) STIR (short tau inversion recovery), a sagittal-oblique T2-weighted (T2W) SPAIR (spectral adiabatic inversion recovery) and a 3D PDW (proton density weighted) SPACE. Images were evaluated for anatomical anomalies compressing the brachial plexus and for abnormal T2W signal within plexus elements. Patients with abnormal MR imaging findings underwent surgical exploration. RESULTS: Seven out of 30 patients were identified with unambiguous morphological correlates of TOS. These were verified by surgical exploration. Correlates included fibrous bands (n = 5) and pseudarthrosis or synostosis of ribs (n = 2). Increased T2W signal was detected within compressed plexus portion (C8 spinal nerve, inferior trunk, or medial cord) and confirmed the diagnosis. CONCLUSIONS: The clinical suspicion of TOS can be diagnostically confirmed by MRN. Entrapment of plexus structures by subtle anatomical anomalies such as fibrous bands can be visualised and relevant compression can be confirmed by increased T2W signal of compromised plexus elements. KEY POINTS: • MR neurography (MRN) can aid the diagnosis of thoracic outlet syndrome (TOS). • Identifiable causes of TOS in MRN include fibrous bands and bony anomalies. • Increased T2W signal within brachial plexus elements indicate relevant nerve compression. • High positive predictive value allows confident and targeted indication for surgery.

Endothelin-1 concentration in plasma is increased after jogging but decreased after cycling in healthy men.

Endothelin-1 plays an important role as a paracrine factor in the regulation of regional blood flow. Plasma levels may represent the net result of spill-over from local stimulation/release and elimination of endothelin-1. In order to compare changes in the concentration of endothelin-1 in the plasma of subjects performing different types of sports exercises we measured immunoreactive endothelin-1 in healthy volunteers ( n=20) performing in random order jogging on a treadmill and cycling on a bicycle ergometer, for 30 min each. Plasma immunoreactive endothelin-1 increased significantly after jogging (2.13+/-0.8 pg/ml versus 2.6+/-0.8 pg/ml, before and after exercise, respectively, P<0.03), whereas it decreased after cycling (2.45+/-0.76 pg/ml versus 2.25+/-0.9 pg/ml, before and after exercise, respectively, P<0.03). We suggest that microtraumatizing effects on the endothelial lining are more pronounced during jogging than during cycling, resulting in a greater increase in plasma endothelin-1, which is too high to be immediately eliminated by the lung despite exercise-induced enhanced pulmonary perfusion. In contrast, similarly enhanced lung perfusion together with a relatively lower stimulation of endothelin-1 compared with jogging, may explain the net decrease in plasma after cycling.

[Muscle ultrasound in neuromuscular diseases]. / Muskelsonographie bei neuromuskulären Erkrankungen.

Imaging modalities are the only noninvasive methods that provide morphological information on skeletal muscles. In neuromuscular diseases, electrodiagnostic investigations are routinely employed in the diagnostic process, although they only deliver functional information. Thus, imaging and electro-diagnostic methods are not in competition, but complement each other. Each method has its specific indications. The technique and diagnostic value of muscle ultrasound in neuromuscular diseases are presented in this review.

Creatine monohydrate in DM2/PROMM: a double-blind placebo-controlled clinical study. Proximal myotonic myopathy.

The efficacy and safety of creatine monohydrate (Cr) in patients with myotonic dystrophy type 2/proximal myotonic myopathy were studied in a small placebo-controlled double-blind trial. Twenty patients received either Cr or placebo for 3 months. After 3 months, there were no significant differences of muscle strength as assessed by hand-held dynamometry, testing of maximum grip strength, Medical Research Council scoring, and the Neuromuscular Symptom Score between the two groups. Some measures indicated trends toward mild improvement with Cr. Myalgia improved in two patients.