Cranial nerve vascular compression syndromes of the trigeminal, facial and vago-glossopharyngeal nerves: comparative anatomical study of the central myelin portion and transitional zone; correlations with incidences of corresponding hyperactive dysfunctional syndromes.

OBJECTIVE: The aim of this study was to evaluate the anatomy of the central myelin portion and the central myelin-peripheral myelin transitional zone of the trigeminal, facial, glossopharyngeal and vagus nerves from fresh cadavers. The aim was also to investigate the relationship between the length and volume of the central myelin portion of these nerves with the incidences of the corresponding cranial dysfunctional syndromes caused by their compression to provide some more insights for a better understanding of mechanisms. METHODS: The trigeminal, facial, glossopharyngeal and vagus nerves from six fresh cadavers were examined. The length of these nerves from the brainstem to the foramen that they exit were measured. Longitudinal sections were stained and photographed to make measurements. The diameters of the nerves where they exit/enter from/to brainstem, the diameters where the transitional zone begins, the distances to the most distal part of transitional zone from brainstem and depths of the transitional zones were measured. Most importantly, the volume of the central myelin portion of the nerves was calculated. Correlation between length and volume of the central myelin portion of these nerves and the incidences of the corresponding hyperactive dysfunctional syndromes as reported in the literature were studied. RESULTS: The distance of the most distal part of the transitional zone from the brainstem was 4.19 ± 0.81 mm for the trigeminal nerve, 2.86 ± 1.19 mm for the facial nerve, 1.51 ± 0.39 mm for the glossopharyngeal nerve, and 1.63 ± 1.15 mm for the vagus nerve. The volume of central myelin portion was 24.54 ± 9.82 mm(3) in trigeminal nerve; 4.43 ± 2.55 mm(3) in facial nerve; 1.55 ± 1.08 mm(3) in glossopharyngeal nerve; 2.56 ± 1.32 mm(3) in vagus nerve. Correlations (p < 0.001) have been found between the length or volume of central myelin portions of the trigeminal, facial, glossopharyngeal and vagus nerves and incidences of the corresponding diseases. CONCLUSION: At present it is rather well-established that primary trigeminal neuralgia, hemifacial spasm and vago-glossopharyngeal neuralgia have as one of the main causes a vascular compression. The strong correlations found between the lengths and volumes of the central myelin portions of the nerves and the incidences of the corresponding diseases is a plea for the role played by this anatomical region in the mechanism of these diseases.

Swallowing therapy--a prospective study on patients with neurogenic dysphagia due to unilateral paresis of the vagal nerve, Avellis' syndrome, Wallenberg's syndrome, posterior fossa tumours and cerebellar hemorrhage.

BACKGROUND: No studies exist dealing with the outcome of dysphagic patients with posterior fossa (IV. ventricle) tumours (PFT) or cerebellar hemorrhage (CH), and the outcome of patients with Wallenberg's syndrome (WS) after functional swallowing therapy (FST) has so far not been studied in detail. Patients and methods. 208 patients with neurogenic dysphagia (ND) who were consecutively admitted for functional swallowing therapy (FST) over a 3 year period to our hospital were examined clinically, by use of a videofluoroscopic swallowing study (VFSS) and/or fibreoptic evaluation of swallowing (FEES). The most frequent etiology was stroke (48%), followed by CNS tumours (13%). In the present study we defined three groups. Group 1 comprised 8 patients with PFT or CH. Group 2 consisted of 27 patients with WS, which was the leading cause among patients with non-hemispheric stroke. Since in WS a vagal nerve paresis due to affection of the Nucleus ambiguus occurs, 8 patients with Avellis' syndrome or unilateral paresis of the vagal nerve served as controls and were defined as group 3. Findings. In the three groups, functional feeding status showed significant improvement after FST comprising methods of restitution, compensation and adaptation, each of which were applied in more than 80% of patients. Outcome was, however, significantly worse in group 1 as compared to group 2 and in group 2 as compared to group 3. Dysfunction of the upper esophageal sphincter and reflex triggering were significantly more severely disturbed in groups 1 and 2 as compared to group 3. Group 1 showed significantly more severe disturbances of the oral phase as compared to groups 2 and 3. After FST, more than 50% (5/8) of group 1 and 30% (8/27) of WS patients (group 2) were dependent on tube feeding, whereas all patients of group 3 were full-oral feeders. Interpretation. This is the first study dealing with the outcome of dysphagic patients with PFT or CH. Based on our results it can be assumed that in these patients pressure is exerted on both dorsomedial central pattern generators (DMCPGs) for swallowing in a posterior-anterior direction. Due to the importance of the DMCPGs for swallowing, bilateral (and often MRI-invisible) lesions seem to be very harmful. For a better understanding of the pathomechanism responsible for ND in patients with PFT or CH, modern imaging methods such as proton magnetic resonance spectroscopy should be used for studying metabolic changes in the dorsal medulla in the future. Since the outcome of patients with WS with regard to dependence of tube feeding was not associated with the site or size of the lesion, it may due to the individual asymmetry of the swallowing-dominant forebrain hemisphere - depend on the side of the medullary infarction.

Vagal paraganglioma: the Jefferson experience.

Vagal paraganglioma is a rare tumor of neural crest origin. Although the literature is in agreement with regard to epidemiology, diagnosis, and tumor biology, there is some controversy over treatment modalities for these patients. We performed a nonrandomized retrospective study in a large single-institution series of patients (n = 19) in whom vagal paraganglioma was diagnosed. General statistics included age, male/female ratio, tumor size, and duration of follow-up. Other variables such as signs and symptoms at presentation, family history, multicentricity, metastatic disease, and secretion of catecholamines were included. CT scan, MRI, and angiography were used in combination for diagnostic purposes as well as for treatment planning. Preoperative embolization was performed in 5 of the more recently treated patients. Current issues regarding the use of preoperative embolization and choice of surgical approach were analyzed. In this article the possibility and sequela of vagus nerve-sparing procedures will be presented. Operative complications and postoperative morbidity related to cranial neuropathies will be discussed. The rationale for performing adjunct procedures, including cricopharyngeal myotomy and vocal fold medialization, to facilitate the rehabilitation of patients with postoperative cranial nerve deficits will be given. Our findings and recommendations will be compared with currently accepted treatment protocols in conjunction with a review of the literature.

Vagal impairment in elderly Chagas disease patients: a population-based study (the Bambuí study).

BACKGROUND: Chagas disease (ChD) will become predominantly a disease of the elderly, as a consequence of the effectiveness of control measures in many Latin American countries. The effects of the disease in old age have received little attention. We investigated the effects of ageing in the association between cardiac vagal impairment, a typical feature of ChD, and chronic Trypanosoma cruzi infection. METHODS: The study sample of this cross-sectional study consists of 1014 subjects ≥ 60 years old (mean age = 68.3; SD = 6.9) residing in Bambuí City (Southeast Brazil). ECG was recorded and one-breath sinus arrhythmia test was performed. Maximal expiratory over the minimal inspiratory (E:I) ratio and heart rate variability (HRV) measurements were calculated. Ordinal logistic regression was used to assess the relation between vagal indexes and chronic T. cruzi infection. RESULTS: The prevalence of T. cruzi infection was 32.0% and of major ECG abnormalities, 43.4%. Among individuals aged 60-69 years, T. cruzi infection was significantly and independently associated with reduced SDNN (OR 0.38; 95% CI 0.27-0.53), RMSSD (OR 0.48; 0.34-0.67) and EI: ratio (OR 0.45; 95% CI 0.33-0.63). Among individuals aged >70 years, no significant odds ratios were found in either the unadjusted or the adjusted analysis. The presence of major ECG abnormalities did not affect the association between vagal indexes and T. cruzi infection. CONCLUSIONS: Disease-specific vagal cardiac dysfunction was observed in ChD individuals below 70. However, further ageing interferes significantly with vagal heart modulation, attenuating the difference of HRV indexes between ChD and non-ChD subjects.

[Autonomic cardiovascular regulation in patients with tics and Tourette syndrome].

Autonomic cardiovascular regulation has been assessed in patients aged 4-15 years with Tourette syndrome (n = 22) and other tic disorders (n = 48). Symptom significance was estimated by a number of hyperkinetic episodes per 20 minutes, tic scale and variants of the disease course. The functional condition of autonomic nervous system was studied clinically and using spectral analysis of heart rate variability in both upright and supine positions. Negative correlation between the ratio of sympathetic and vagus influences and severity of the disease was found: the severer were tic symptoms, the stronger was a trend to vagotonia (beta = -0.36; p < 0.0025; F > 4.0). In orthostatic test, patients with Tourette syndrome demonstrated an unfavorable hypersympathicotonic type of cardiovascular system reaction. Patients were treated during 4 weeks with glycinum (0.2 +/- 0.1 mg/day), phenibutum (0.5 +/- 0.25 mg/day), clonazepam (1.5 +/- 0.5 mg/day), tiapride (200 +/- 100 mg/day), haloperidol (1-1.5 mg/day), rispolept (2 mg/day). There was no negative effect of the drugs on heart rate variability. On the contrary, the therapy reduced hyperkinetic symptoms and corrected autonomic influences on the sinus rhythm. It is suggested that changes in autonomic cardiovascular regulation might be of secondary character and do not need any special correction.