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case of multifocal motor neuropathy that highlighted the complementary role of ultrasonography. A 40-year-old man presented with a 2-year history of progressive left-sided weakness without sensory symptoms. A nerve conduction study revealed partial conduction block in two nerves. Anti-GM1 antibody was negative and other labora- tory studies, unremarkable. Ultrasonography showed focal nerve enlargement of the right median nerve at the forearm and left ulnar nerve at the elbow. His weakness improved com- pletely after intravenous immune globulin. Ultrasonography revealed focal enlarge- ment of the median and ulnar nerves. Cross-sectional areas of the right and left median nerves at the wrist were normal, as were those of the left median nerve at the forearm, the right and left median nerves at the upper arm, and the right ulnar nerve at the elbow. However, cross-sectional areas of the right median nerve at the forearm and In sex-matched controls (37 cases; 75 hands, n=39 female, n=6 male), mean distal cross-sectional area was 0.79 ± 0.13 cm 2 (0.59 to 0.11 cm 2 ) and 0.77 ± 0.1 cm 2 (0.53 to 0.1 cm 2 ) in the right and left median nerves, respectively. Mean cross-sectional area of participants was significantly higher than in controls. Nerve conduction studies in 27 participants revealed absent evoked motor response in four individuals (n=3 right, n=1 left). In 24 cases, mean distal motor latency and com- pound muscle action potential of the right median nerve was 5.8 ± 1.4 (4.2 to 11.4) s and 8.65 ± 3.0 (3.3 to 10.3) mV, respectively. On the left (26 cases), it was 5.5 ± 1.8 (3.3 to 10.3) s and 8.3 ± 3.7 (0.6 to 15.8) mV, respectively. Median nerve sensory nerve action potentials were absent in 16 participants (n=10 bilateral, n=4 right, n=2 left). Mean sensory latencies were 4.5 ± 2.4 (2.5 to 12) s and 3.4 ± 0.7 (2 to 4) s in the right (n=13) and left (n=14) sides, respectively. Corresponding mean sensory amplitudes were: ƒ ƒ Right 7.2 ± 5.3 (1.5 to 23) mV ƒ ƒ Left: 9.9 ± 5.9 (2.3 to 22.1) mV Conduction velocities were: ƒ ƒ Right 35.6 ± 11 (11.7 to 58) m/s ƒ ƒ Left 43.7 ± 13 (22.2 to 68.6) m/s

the left ulnar nerve were increased at 15.2 mm 2 and 11.1 mm 2 , respectively. Cross-sectional area of the right and left median nerves at the upper arm was normal. Cross-sectional area of the right and left ulnar nerves at the wrist was normal. Cross-sectional area of the right ulnar nerve at the elbow was normal (3.5 mm 2 ), but of the left ulnar nerve, increased at 11.1 mm 2 . Dr. Im Suk explained that multifocal motor neuropathy is treatable, and its differen- tiation from lower motor neuron disease is crucial. Evidence of conduction block or positive immune globulin M anti-GM1 is considered an important diagnostic marker. Some individuals with atypical multifocal motor neuropathy, however, exhibit no detectable conduction block nor anti-GM1 antibodies. Dr. Im Suk concluded that ultrasonography can be valuable in supporting the diagno- sis of multifocal motor neuropathy. www.practiceupdate.com/c/70783 MRI in 19 individuals showed mean distal cross-sectional area of the right median nerve of 1.55 ± 0.49 (range 1 to 2.7) cm 2 and left median nerve, 1.57 ± 0.4 (range 1 to 2.7) cm 2 . Dr. Nalini noted, “Ultrasound of the nerves is an emerging, painless, easily accessi- ble, affordable, and sensitive modality to study peripheral as well as proximal nerves to understand their involvement in carpal tunnel syndrome. Particularly in this disorder, if we need objective follow-up assessment of any specific therapy, ultra- sonography may be used repeatedly. These features of ultrasonography and its great utility in entrapment neuropathies prompted us to take up this study, also to obtain data in normal controls for com- parison and correlation. We plan to utilize ultrasonography to assess all our cases of carpal tunnel syndrome.” Dr. Nalini emphasized the importance of ultrasonography as a sensitive, cheaper, and effective alternate to MRI to confirm carpal tunnel syndrome. Cross-sectional area of the proximal median nerve may be used to predict severity of carpal tunnel syndrome. Moreover, mean and inlet cross-sectional area may be valid and easy-to-acquire parameters for routine clinical use in con- firming carpal tunnel syndrome. www.practiceupdate.com/c/70789

conduction block is the hallmark of the disorder. With early diagnosis and treatment with intravenous immune globulins, multifocal motor neuropathy is treatable, at least during the first years of disease. The rarity of multifocal motor neuropathy has limited the number of studies of clin- ical features and response to long-term treatment. Dr. Oberreiter concluded that the preva- lence of multifocal motor neuropathy in Austria is similar to the few reports from other countries. The present results cor- roborate previous results in terms of clinical, electrophysiological, and laboratory fea- tures of multifocal motor neuropathy. Intravenous immune globulins continue to be the most effective treatment for mul- tifocal motor neuropathy. In most cases, however, deterioration occurs over the long term. Jung Im Suk, MD, of the Catholic University of Daegu, School of Medicine in Daegu, South Korea, and colleagues described a All participants voiced sensory complaints. A total of nine patients (30%) also suffered from motor deficits. Sensitivity of Tinel sign/Phalen’s maneuver was 40% and 63.3%, respectively. Using ultrasonogra- phy, cross-sectional area at the pisiform bone level was >0.1 cm 2 . at presentation was 41.6 ± 10.5 (27 to 61) years. Clinically, 28 (93.3%) suffered from bilateral carpal tunnel syndrome (n=4 symmetrical, n=24 asymmetrical) and 2 exhibited unilateral involvement. The duration of illness varied from 2 months to 8 years.

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