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C D Reimers

Publications and source records attributed to C D Reimers.

At least 19 recordsLinked to original sources
PubMed2004

[Detection of fasciculations and other types of muscular hyperkinesias with ultrasound].

Muscular hyperkinesias can be visualized by means of ultrasound (US): Ultrasonographic detection of fasciculations has been best evaluated. However, so-called ripplings, myoclonias and choreatic hyperkinesias as well as tremores can also be visualized by US. Muscular US has proven as a precise imaging technique for the detection of fasciculations. Fasciculations are brief, localized muscle twitches, usually lasting for 0.2 - 0.5 seconds. Some myoklonias may present similar in US, others present with a longer duration. In addition, muscle US allows a very easy and reliable detection of tremor frequency. This article reviews the present ultrasonographic facilities in the detection of muscular hyperkinesias and gives future perspectives.

Fasciculation↗
PubMed2003

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.

Adult↗
PubMed2002

[Muscle ultrasound in neuromuscular diseases].

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.

Adult↗
PubMed2001

Selective thigh muscle atrophy in trans-tibial amputees: an ultrasonographic study.

In trans-tibial amputees, PTB (patellar tendon bearing) prostheses provide almost physiological mobility of the knee joint in the sagittal plane. Nevertheless, there are characteristic adaptations of the knee joint muscles. Myosonography is a suitable method for depicting muscle atrophy and hypertrophy due to muscle dysfunction. The present study was intended to assess anatomical alterations of thigh muscles in trans-tibial amputees wearing a PTB prothesis. Thicknesses and cross-sectional areas of the quadriceps femoris, sartorius, gracilis, semitendinosus and biceps femoris muscles were determined ultrasonographically on both limbs in 17 amputees with a PTB prothesis. The gait was analysed using an optoelectronical system, force plates and surface electromyography of the vastus lateralis and biceps femoris muscles. Quadriceps femoris and sartorius muscles of the amputated extremity exhibited significant atrophy compared with the contralateral limb (reduction of muscle thickness ranged between 11.7% and 30.4%), whereas the gracilis and hamstring muscles were not significantly affected. Even the quadriceps femoris muscle of the non-amputated limb showed a slight atrophy compared with a reference group. Increased echointensities were found predominantly in the quadriceps muscle on the amputated leg. During gait, electromyographical activity within the amputated limb was reduced in the vastus lateralis and increased in the biceps femoris muscle. Even long-term adaptation to PTB prostheses results in characteristic deviation from normal gait. Atrophy occurs in the ventral thigh muscles, predominantly on the amputated leg, whereas the dorsal thigh muscles are hardly affected, probably due to compensatory hyperactivity.

Adolescent↗
PubMed2000

Proximal myotonic myopathy: evidence for anticipation in families with linkage to chromosome 3q.

OBJECTIVE: To investigate anticipation in proximal myotonic myopathy (PROMM). BACKGROUND: PROMM is a recently described autosomal dominantly inherited disorder similar to but distinct from myotonic dystrophy (DM). DM belongs to the group of inherited disorders with anticipation caused by an unstable trinucleotide repeat expansion. In PROMM, no mutation has been identified, although PROMM has recently been mapped to a gene locus on chromosome 3q. METHODS: We investigated 10 German families with the PROMM phenotype and linkage to chromosome 3q. We based our analysis of anticipation on the age of disease onset. Anticipation was assumed if the offspring had first symptoms earlier in life than his or her affected parent. For statistical analysis Independence Estimating Equations (IEE) and a Monte-Carlo bootstrap were used. RESULTS: In 27 affected living parent-offspring pairs from these 10 families, the mean difference of disease onset was 18.8 years with either statistical analysis (p < 10-14 and p < 10-15). The mean disease onset interval in years was greater in father-offspring as compared to the mother-offspring pairs (p < 0.05; IEE). CONCLUSION: Our findings suggest the occurrence of anticipation in parent-offspring pairs from families with the PROMM phenotype and linkage to chromosome 3q. The different disease onset intervals in mother-offspring and father-offspring pairs could indicate a mild parent-of-origin effect. These observations are compatible with the suggestion that PROMM, like DM, may be a trinucleotide repeat associated disorder. In contrast to DM, anticipation in PROMM is milder, a congenital form does not seem to occur, and fertility does not appear to be affected.

Adolescent↗
PubMed2000

Exploration of motor cortex excitability in a diabetic patient with hemiballism-hemichorea.

Hemiballism-hemichorea in older patients with hyperglycemia, associated with high signal intensity in the contralateral striatum on T1-weighted magnetic resonance scans, is now an accepted clinical entity. We present an additional patient with this disorder. Using transcranial magnetic stimulation, we show that intracortical inhibition in the motor cortex contralateral to hemiballism-hemichorea is increased. This finding is discussed in the context of current models of basal ganglia-thalamo-cortical connectivity.

Aged↗
PubMed2000

Imaging in myology: a neurologist's perspective.

A bewildering array of neuromuscular diseases exist, but the number of tools to test for these is relatively small. Fortunately, much of the information that is needed for day-to-day diagnosis and management is readily obtained using conventional techniques. It is indisputable, however, that the information that is gained from imaging tests advances a physician's comprehensive understanding of the patient's condition, its severity, and the prognosis. In many ways, ultrasound is an adequate provider of this information. In key uses, magnetic resonance imaging (MRI) provides information that is otherwise unobtainable. This article summarizes some of the issues that a myologist is confronted with and how imaging aids in the situation.

Diagnostic Imaging↗
PubMed2000

Boxing and running lead to a rise in serum levels of S-100B protein.

Permanent neurological dysfunction is the primary medical concern of boxing. Recently it was reported that patients presenting elevated levels of the glial protein S-100B in serum after minor head injuries are more prone to develop neuropsychological deficits than patients with lower levels of S-100B protein. We assessed this protein before and after amateur boxing competitions (n = 10) and sparring bouts (n = 15). In several control groups, we investigated S-100B levels of participants before and after a 25 km race (n = 11), jogging (10 km, n = 12), short-term running (n = 12), and heading footballs (n = 12). There was an increase in S-100B protein after boxing and the running disciplines but not after ergometer cycling or soft heading of footballs. The increase in S-100B protein concentrations due to competitive boxing and after the 25 km race was significantly higher than that after performing other disciplines (p < 0.001). There was no significant difference between the increases caused by sparring and the running disciplines (p = 0.21). The number and severity of the strikes to the head correlated significantly with the increase in the S-100B protein levels. Levels of S-100B protein known to be associated with neuropsychological deficits were not reached in our study. In professional boxing, much higher levels are to be expected and would be worthy of investigation.

Adolescent↗
PubMed2000

Motor cortex fatigue in sports measured by transcranial magnetic double stimulation.

PURPOSE: Besides peripheral mechanisms, central fatigue is an important factor limiting the performance of exhausting exercise in sport. The mechanisms responsible are still in discussion. Using noninvasive transcranial magnetic stimulation (TMS) in a double-pulse technique, we sought to assess fatigue of the motor cortex after exhaustive anaerobic strain. METHODS: 23 male subjects (22-52 yr) taking part in the study were requested to accomplish as many pull-ups as possible until exhaustion. The amount of physical lifting work was recorded. Before and immediately after the task, intracortical inhibition (ICI) and facilitation (ICF) were measured by a conditioned-test double-pulse TMS method for the right brachioradialis (BR) and abductor pollicis brevis muscle (APB). RESULTS: After exercise, ICF was significantly reduced in the BR but not in the APB. ICI was not altered. Changes tended to normalize within 8 min after the task. The amount of lifting work accomplished showed significant correlation to the values of ICF reduction (r = 0.73). Moreover, the baseline values of ICF before exercise were also significantly correlated to the lifting work (r = 0.63). CONCLUSIONS: Because double-pulse TMS gives access to the motor cortex independently of spinal or peripheral mechanisms, reduced ICF reflects decreased excitability of interneuronal circuits within the motor cortex. We suggest that ICF measures motor cortex fatigue after exhausting strain specifically for the muscles performing the task. Gamma-aminobutyric acid (GABA)-ergic neurotransmission is possibly involved in the mechanisms mediating central fatigue. Double-pulse TMS may be a useful tool in the control of training in sports as well as in the detection of pathological central fatigue in overreaching and in the prevention of overtraining.

Adult↗
PubMed1999

Linkage of proximal myotonic myopathy to chromosome 3q.

We performed genetic linkage analysis in nine German proximal myotonic myopathy (PROMM) families using DNA-markers D3S1541 and D3S1589 from the region of the recently discovered gene locus of myotonic dystrophy type 2 (DM2) on chromosome 3q. Two-point analysis supplied an lod score of 5.9. We conclude that a gene causing PROMM is located on chromosome 3q. PROMM and DM2 may be allelic disorders or may be caused by closely linked genes.

Chromosome Mapping↗
PubMed1999

Outpatient coronary stenting: femoral approach with vascular sealing.

Miniaturized devices and pressures for increased patient convenience and lowered cost have shortened length of stay for coronary interventions. A cohort of 60 patients was recruited to assess the feasibility of outpatient stenting with vascular sealing. Patients with stable and unstable angina or myocardial infarction > 24 hours were considered for this strategy. Mean time to hemostasis, ambulation and discharge were 6.1, 256 and 296 minutes, respectively, for the 6F group, and 11.0, 351 and 489 minutes for the 7 to 8F group. No acute procedural complications occurred, and there were no ischemic complications at 24 hours or 1 month. There was 1 pseudoaneurysm requiring surgical correction, but no other access site requiring treatment. The cost saved using the 6F approach is estimated at $478 and using the 8F approach, $437. Outpatient stenting using vascular sealing is feasible and safe, and may lead to significant nationwide cost reductions in the range of $40,000,000 yearly.

Ambulatory Care↗
PubMed1999

Riluzole does not have an acute effect on motor thresholds and the intracortical excitability in amyotrophic lateral sclerosis.

Intracortical excitability in amyotrophic lateral sclerosis (ALS) is impaired. The effectiveness of the glutamate antagonist riluzole (Rilutek, Rhône-Poulenc Rorer) in ALS has been shown in clinical studies. In healthy subjects it modifies intracortical excitability in a frequently used double-stimulus paradigm of transcranial magnetic stimulation (TMS). Under riluzole intracortical inhibition is enhanced in healthy individuals, although not always significantly, whereas intracortical facilitation has been described as reduced [10, 11]. We wanted to find out whether riluzole affects and potentially rebalances impaired intracortical excitability in ALS. We, therefore, enrolled 13 patients with clinically and electromyographically confirmed ALS into this study. Five patients had to be excluded because motor thresholds were too high to get reliable motor evoked potentials (MEPs). In the remaining 8 patients, mean age was 59.9 +/- 11.9 years (+/- standard deviation) and mean symptom duration 9.6 +/- 2.5 months. Intracortical excitability was assessed before and 1.5 hours after the first intake of a loading dose of 100 mg of riluzole using a conventional paired-pulse TMS paradigm with interstimulus intervals (ISI) ranging from 1-30 ms and intensities adjusted to yield MEPs of 1.0 mV for test pulses and of 90% active motor threshold for conditioning pulses. Patients' baseline results were compared to those of 9 age-matched, healthy control subjects. Before drug intake, motor thresholds did not differ between groups, but there was significantly less intracortical inhibition in the ALS patient group. Riluzole intake did not significantly alter motor thresholds or intracortical excitability in the ALS patients. We conclude that riluzole does not immediately influence intracortical excitability in ALS. Our results are in contrast to the findings of Stefan et al (1998) [14] where a partial normalization of intracortical inhibition in ALS was observed after at least 5 days of drug intake. The difference between that study and our result may indicate a delayed onset of riluzole's influence on intracortical excitability.

Aged↗
PubMed1999

Ultrasound of radial, ulnar, median, and sciatic nerves in healthy subjects and patients with hereditary motor and sensory neuropathies.

This study was conducted to evaluate the capability of ultrasonography to visualize extremity nerves. Fifty healthy women and men and 10 patients suffering with hereditary motor and sensory neuropathy (HMSN) were examined. The radial nerve lateral to the humerus, ulnar nerve distal to the cubital tunnel, median nerve in the middle of the forearm and proximal to the palmar crease, sciatic nerve in the middle of the thigh and tibial and common peroneal nerves just distal to their bifurcation, were investigated, employing a 7.5-MHz electronic linear-array transducer. In healthy subjects, the median, ulnar and radial nerves could be identified in all cases, the sciatic nerve in 37 cases, the tibial and peroneal nerves in 10 cases. The median values of thicknesses were about 3 mm for arm nerves and 6 to 7 mm for the sciatic nerve. Nerve sizes did not correlate with subjects' height, weight or age. In the majority of the patients, arm and sciatic nerves were also visible. Thicknesses were normal in 34, increased in 11 and decreased in six of 51 nerves. In conclusion, ultrasonography allows reliable imaging of the major arm nerves and, occasionally, facilitates visualization of the sciatic, tibial and peroneal nerves in healthy subjects. Nerve size and structure did not differ significantly between patients with HMSN and healthy subjects.

Adolescent↗
PubMed1999

Continuous wave Doppler ultrasound for evaluation of vasomotor tone of the radial artery.

OBJECTIVE: At present, the sympathetic skin response (SSR) is the only routinely employed technique for evaluating the autonomic function of peripheral nerves. The present study was conducted in order to compare SSR to continuous wave Doppler (CWD) of the radial artery in both healthy control subjects and patients with lower brachial plexus lesions. METHODS: Both methods were performed in 50 healthy volunteers (aged 23 to 70 years; mean age and standard deviation, 39.6+/-14.3 years) and six patients presenting with severe lesions of the lower brachial plexus (aged 22 to 60 years; mean age, 37.6+/-16.0 years). RESULTS: In each control subject, a SSR could be evoked with a mean latency of 1.2+/-0.2 s and a mean amplitude of 2.9+/-1.5 mV. In 45 healthy subjects, CWD revealed both a reduction of systolic, diastolic, and mean peak blood flow velocity after electrical (ES) and acoustic (AS) stimulation as well as after inspiratory cough (IC). The mean latencies to the decrease in flow velocity decrease amounted to 1.8+/-0.7, 2.0+/-0.7, and 1. 4+/-0.4 s, respectively. The resistance (Pourcelot) index increased significantly. CWD failed to show changes of blood flow velocity in five healthy subjects due to high sympathetic tone (no baseline diastolic blood flow) or instability of blood flow caused by respiration. In patients with lower brachial plexus lesions, SSR was diminished and changes in blood flow could not be observed on the affected side. CONCLUSION: CWD sonography allows easy quantitative assessment of arteriolar tone in healthy subjects and patients with autonomic nerve lesions of the limbs.

Acoustic Stimulation↗
PubMed1999

Quantitative ultrasonography in focal neuropathies as compared to clinical and EMG findings.

OBJECTIVE: The aim of this study was to assess the diagnostic value of muscle ultrasonography in focal neuropathies. SUBJECTS AND METHODS: 100 patients suffering from unilateral symptoms or signs on the extremities indicating injuries of nerve roots, plexus, or peripheral nerves were prospectively examined by manual muscle testing (MMT), electromyography (EMG), and quantitative muscle ultrasonography. Muscle thickness and echointensity (gray scale analysis) were measured and compared to the results from 28 control subjects. RESULTS: Ultrasonography was as sensitive as MMT and EMG in detecting muscle involvement. Ultrasonography and EMG were complementary. In 27% of 85 paretic muscles, only one of both techniques revealed pathological findings. Increased echointensity was seen in 82%, atrophy in 31% of pathological muscles. Earliest ultrasonographic abnormalities and pathological spontaneous activity in EMG appeared 10 days after the injury. The inter-observer agreement of ultrasonography was slightly, but significantly lower than that of EMG. CONCLUSION: Muscle ultrasound can visualize anatomical abnormalities such as muscle atrophy and mesenchymal abnormalities in lesions of nerve roots, plexus, and peripheral nerve lesions.

Adolescent↗
PubMed1999

Lesion development in Marburg's type of acute multiple sclerosis: from inflammation to demyelination.

We report a patient who suffered from acute inflammatory CNS demyelination and underwent two consecutive diagnostic stereotactic brain biopsies during the early disease course. The first lesion was drawn 33 days after the onset of disseminated neurological symptoms. Macrophages and T lymphocytes diffusely infiltrated small vessel walls and the white matter. mRNA for tumor necrosis factor alpha (TNFalpha) and inducible nitric oxide synthase (iNOS) was abundantly expressed. Myelin sheaths were entirely preserved. The second biopsy 76 days later showed confluent demyelinating lesions with a diffuse infiltration of macrophages that were positive for myelin debris, activation markers and TNFalpha and iNOS mRNA. IgG and C9neo deposits were found along myelin sheaths. The patient had received intravenous immunoglobulins (IVIG) prior to biopsy. Findings from this single patient affirm that demyelination follows the migration of inflammatory cells from the circulation into the white matter with subsequent inflammation and demyelination. Inflammation alone may be sufficient to cause significant clinical deficits without demyelination. Inflammatory mediators such as TNFalpha and NO are involved at very early stages in the pathogenetic process. IVIG treatment may lead to the deposition of immunoglobulins and to the activation of the complement cascade, but the clinical relevance of this particular finding remains uncertain.

Acute Disease↗