[The method of axonal stimulation (AS) for jitter evaluation in the diagnosis of neuromuscular transmission disorders]. / Metoda stymulacji aksonalnej do oceny jitteru w diagnostyce zaburzen transmisji nerwowo-miesniowej.

The results of jitter measurements in 15 patients with myasthenia gravis and 10 control group persons are presented using single fiber emg (SFEMG) method during weak voluntary activation and intramuscular AS. The method of AS is described, advantages of its use in evaluation of neuromuscular transmission disorders, some limitations and technical traps that the investigator encounters are presented. Jitter values obtained by both methods are compared and existing differences are discussed taking into account two variants of jitter origin.

Muscular fatigability in mitochondrial myopathies. An electrophysiological study.

A frequent occurrence of ophthalmoplegia and muscle fatigability in mitochondrial myopathy (MAM) often makes its differential diagnosis from myasthenia rather difficult. Neuromuscular transmission was investigated in 9 patients with MAM, presenting marked fatigability. The aim of the study was to see whether there were any other causes of muscle fatigability in addition to the metabolic factors. Classical electrostimulation as well as the SFEMG, which is very sensitive in detecting neuromuscular transmission disorders, were used. The findings were far from uniform: we found normal neuromuscular transmission in 5 cases, in 3 patients we observed slight abnormalities of neuromuscular transmission, in 1 case neuromuscular transmission disturbances seemed to be of neurogenic origin. Our results allow an assumption that the causes of muscle fatigability in MAM are of a much more complex nature than it has been anticipated. They might depend not only on the metabolic disorders within the muscle fibre itself but also on the impaired function of the peripheral nerve or of the neuromuscular junction. All the mechanisms combined may also play a role, though in individual patients the contribution of particular factors responsible may vary.

[Facilitation phenomenon in electrophysiological diagnosis of myasthenia gravis]. / Zjawisko torowania w elektrofizjolo-gicznej diagnostyce miastenii.

A group of 10 patients with atypical result of repetitive stimulation was selected out of the patients examined in our EMG Laboratory. The diagnosis of myasthenia was clinically confirmed. In all those 10 patients no essential amplitude decrement was found on stimulation, so the electrophysiological confirmation of the diagnosis was lacking. On repetitive stimulation (3 Hz) all increment of the response was observed and also post-tetanic facilitation was present. In SFEMG moderate neuromuscular transmission disturbances were found in those patients. It suggests that, sometimes, facilitation may reflect disturbed neuromuscular transmission even despite the absence of the typical amplitude decrement.

Disintegration of the motor unit in post-polio syndrome. Part II. Electrophysiological findings in patients with post-polio syndrome.

The aim of the study is to investigate the motor unit abnormalities in late postpolio muscular atrophy (PPMA) as compared to those found in patients who had polio 20-30 years prior to examination without any new clinical signs. The quantitative concentric needle EMG and a single fiber EMG techniques were employed. Spontaneous activity, the parameters of individual motor units potentials (MUP), number of complex potentials and their stability, jitter and blocking as well as fiber density (FD) have been evaluated. In PPMA patients (5 subjects) we found in newly weakened muscles: spontaneous activity, high percentage of complex potentials, increased jitter, increased FD. The EMG findings in muscles previously affected but without any signs of progression have been similar. In the patients with stable nonprogressing postpolio muscle atrophy (12) all MUP-s parameters indicated changes similar to PPMA but less marked in initially affected muscle with complete or incomplete recovery as well as sometimes in initially clinically unaffected muscles. These findings suggest that the signs of ongoing reinnervation processes persist many years after polio and that PPMA occurring later in life represents disintegration of the previously reinnervated motor units. It is still unclear whether this disintegration depends on decompensation by different factors of fully reinnervated motor units or whether most of the motor units after polio never regained a stable reinnervation.

Disintegration of the motor unit in post-polio syndrome. Part I. Electrophysiological findings in patients after poliomyelitis.

CN EMG and SF EMG were performed in 12 patients many years after acute poliomyelitis, without symptoms of post-polio syndrome. In 19 muscles with clinical symptoms and in 11 clinically normal muscles chronic neurogenic changes of a similar degree were observed. Fibre density was increased in both groups of muscles. In muscles with clinical symptoms complexes of single fibres with increased jitter and blocking were more frequent than in muscles without clinical manifestations. It seems that the reinnervation after acute polio is a continuing process and thus complete stabilization and integration of the motor unit cannot be achieved.

[A trial of cronassial use in late postpoliomyelitis syndrome]. / Próba stosowania Cronassialu w póznym zespole postpolio.

The results are presented of treatment with gangliosides (Cronassial) in 5 patients with late postpoliomyelitis syndrome. Clinical and electrophysiological examination were done before and after three months of treatment. Only subjective improvement was found. A year-long follow-up failed to fluid progression of the signs and symptoms that, formerly, were progressing slowly. It seems that Cronassial administration (in larger doses and for a longer time) is justified in patients with peripheral motor neuron lesion.

[Reactivity of periodontal vessels in children with insulin-dependent diabetes]. / Reaktywnosc naczyn przyzebia u dzieci z cukrzyca insulinozalezna.

The morphological changes of capillaries and small vessels in diabetes are preceded by functional disturbances. The purpose of the work was assessment of the reactivity of parodontal vessels in children with insulin-dependent diabetes. The study was done in 50 children with this diabetes aged 7 to 17 years, and 45 healthy controls (without parodontal changes). The photoplethysmographic method was used. Nitroglycerine test of Böhme was carried out estimating the pattern of the so called inclination time before and after sublingual nitroglycerine administration. The capillaries of the diabetic children reacted more strongly to nitroglycerin than those of controls. It is concluded that children with diabetes of recent onset have functional vascular disturbances in the parodontium. Photoplethysmography is a simple non-invasive method useful in the assessment of early vascular disturbances in the parodontium of children.

Pseudoselectivity of the neuromuscular block in ocular myasthenia: a SFEMG study.

The patients with pure ocular myasthenia presenting no signs of neuromuscular transmission defect on classical supramaximal repetitive stimulation were studied using SFMG method. Only those patients were selected to the study in whom the diagnosis of the ocular myasthenia was confirmed by the clinical criteria arranged so as to exclude ophthalmoplegia of the other nature. The series comprises 20 patients in whom the results of the supramaximal repetitive stimulation with the recording from the proximal muscles and with the evaluation of posttetanic phenomena were normal. SFEMG examination was performed in the clinically intact EDC muscle and in 17 patients an elongated jitter, sometimes with blocking was found. Among those three patients with normal results two were in full clinical remission, so there was only one patient presenting the symptoms of ocular myasthenia in whom the neuromuscular transmission defect was absent in the EDC. The results justify an admission that the neuromuscular block in ocular myasthenia is only apparently selective; in fact it concerns all the muscles with a different severity and may be detected if properly sensitive diagnostic methods are applied.

[Atypical clinical image of myopathy with abnormal mitochondria (MAM) in our cases]. / Nietypowy obraz kliniczny miopatii mitochondrialnej (MAM) na podstawie przypadków wlasnych.

Two peculiar cases of mitochondrial myopathy are presented. In the first case the diagnostic difficulties are discussed stressing especially the differentiation of the myopathy from myasthenia. In the second cases polyneuropathy signs were evident, which is extremely rare in this myopathy.

[Post-poliomyelitis syndrome. Description of 2 cases]. / Zespól postpolio--na podstawie dwóch przypadków.

The authors describe two cases of slowly progressing damage of the peripheral motor neuron which developed in the patients several tens of years following typical acute poliomyelitis anterior in childhood. The clinical features of these cases and the results of electrophysiological investigations are reported in detail. In the light of these cases and a literature review the authors discuss the clinical findings, course, electrophysiological, virological and immunological investigations, and hypotheses concerning the pathological mechanism of the postpoliomyelitis syndrome.

[Favorable results of the treatment of the hyperkalemic form of periodic paralysis with salbutamol]. / Pomyslne wyniki leczenia salbutamolem hyperkalemicznej postaci porazenia okresowego.

Two cases of hyperkalaemic periodic paralysis with myotonic symptoms were treated successfully with salbutamol. The methods of managing the hyperkalaemic form of periodic paralysis are discussed in brief.

Do true remissions in myasthenia really exist? An electrophysiological study.

To answer the question whether true remissions in myasthenia gravis occurred, 20 patients were studied with a history of evident, typical myasthenia but in full clinical remission. Two control groups served as a comparison: one of 10 healthy volunteers and the other of 10 patients with generalized, presently active myasthenia. In 17 of the 20 patients in remission single-fibre EMG (SFEMG) abnormalities were found, indicating some subclinical disturbances of neuromuscular transmission (in 3 cases the results were overtly pathological, in 11 cases moderately pathological, and in 3 cases slightly pathological). The abnormalities found in the remission group were much less distinct than those in the group with clinically symptomatic myasthenia. A case illustrates these findings: a man in full remission following thymoma extirpation in whom the SFEMG revealed subclinical disturbances of the neuromuscular transmission. Three weeks later a full clinical relapse occurred. The results obtained suggest that in the majority of patients the remissions are only apparently complete. A pathological jitter in a patient in remission calls for special attention: the patient must be spared any immunological stimuli such as vaccination, injections of sera, infections etc.; no drugs can be given which may increase the neuromuscular block; an immunosuppressive course of treatment should be considered; prognosis should be reconsidered.

[Evaluation of treatment of myasthenia with thymectomy (author's transl)]. / Appréciation du traitement de la myasthénie par la thymectomie.

The paper describes the effectiveness of treatment of myasthenia with thymectomy in 136 patients operated on, observed in hospital and 107 examined by questionnaire on late results after 10 years. Exclusive of myasthenia with thymoma, cures were obtained in 26.4%, marked improvement in 19.6%, moderate improvement in 21.4%, improved motor strength in 27.1%, and deterioration was observed in 3.8%. The assessment was based mainly on the amount of cholinergic drugs taken. Early mortality rate was 2,4%, and late mortality 1,9%. Relation of postoperative complications/respiratory and crisis of both kinds to mortality and intraoperative pleural injury also surgical approach and anatomic variants of the thymus were discussed. An influence of the number of proliferating centers on prognosis in myasthenia after thymectomy was nor demonstrated. Thymectomy in a generally accepted and most effective method of treatment in myasthenia.