Evaluation of velopharyngeal function using high-speed cine-magnetic resonance imaging based on T2-weighted sequences: a preliminary study.

The objective was to introduce a new technique for visualizing the three-dimensional (3D) movements of velopharyngeal-related muscles using high-speed cine-magnetic resonance imaging (MRI) based on T2-weighted sequences. The evaluation of phonation- and water swallowing-related events was performed in 11 healthy subjects. Specifically, whether cine-MRI could precisely visualize normal velopharyngeal function during these two events was examined. The 3D movements of the soft palate, superior pharyngeal constrictor muscles, and levator veli palatini muscles were visualized in all 11 subjects. A noteworthy finding was that the magnetic resonance signals of the superior constrictor pharyngeal muscles and the levator veli palatini muscles were significantly higher during phonation and during water swallowing than at rest. This initial study suggests that the 3D movements of velopharyngeal-related muscles can be successfully and precisely visualized without side effects. The magnetic resonance signal changes seen in the superior pharyngeal constrictor and levator veli palatini muscles using the technique described here should be useful to develop better methods of evaluation of velopharyngeal function.

Predicting the therapeutic effect of carbamazepine in trigeminal neuralgia by analysis of neurovascular compression utilizing magnetic resonance cisternography.

The aim of this study was to determine whether the evaluation of neurovascular compression (NVC) using new criteria on magnetic resonance (MR) cisternography improves the prediction of the curative effects of carbamazepine (CBZ) in trigeminal neuralgia (TN). In this study, a new analysis of NVC using MR cisternography was performed retrospectively for 280 patients with clinical signs and symptoms suggesting TN. The new analysis examined whether the site of the NVC was less than 3mm from the edge of the exit point and within the first third of the root entry zone on MR cisternography. Prediction of the curative effects of CBZ using the new evaluation of distance to the NVC improved on the predictive ability of the previous method of calculating the NVC volume (Mantel-Haenszel coefficient, P<0.01). In particular, initial treatment with CBZ 100mg/day for 2 weeks appeared more effective for patients with NVC volumes of ≤5mm3 plus a distance to the NVC of ≤3mm, than for those with NVC volumes >5mm3. The evaluation of NVC on MR cisternography using this new approach appears to be more useful than the previous method for predicting the initial treatment response in patients with TN.

Importance of absorbable surgical sutures for the prevention of stitch abscess after surgery in patients with oral squamous cell carcinoma.

BACKGROUND: To elucidate the significance of absorbable surgical sutures in the occurrence of stitch abscess after surgery in patients with oral squamous cell carcinoma (SCC). MATERIAL AND METHODS: The subjects were 251 patients who underwent excision and/or reconstruction and/or neck dissection for oral SCC using absorbable surgical sutures. Detection rates and characteristics of patients with stitch abscess were retrospectively evaluated by comparing between our present and previous data. RESULTS: There was only one stitch abscess among the 251 patients. A significant difference in the incidence of stitch abscess was found between the present data and our previous data. Of course, no significant correlations were found between the occurrence of stitch abscess using absorbable surgical sutures and the various factors seen in our previous analysis. CONCLUSIONS: A complete switch of surgical sutures from silk to absorbable surgical sutures is needed for surgery in patients with oral SCC.

Variety and complexity of fluorine-18-labelled fluoro-2-deoxy-D-glucose accumulations in the oral cavity of patients with oral cancers.

OBJECTIVES: To elucidate the points that require attention when interpreting fluorine-18-labelled fluoro-2-deoxy-d-glucose ((18)F-FDG)/positron emission tomography (PET) images by demonstration of (18)F-FDG accumulation in various areas of the oral cavity other than primary lesions in patients with oral cancers. METHODS: (18)F-FDG accumulations with a maximal standardized uptake value of over 2.5 in various areas of the oral cavity other than primary lesions were identified in 82 patients with oral cancers. RESULTS: (18)F-FDG/PET-positive areas, excluding primary tumours, included the front intrinsic muscles of the tongue (89.0%), upper and lower marginal parts of the orbicularis oris muscle (64.6%), sublingual glands, palatine tonsil, pharyngeal tonsil, and lingual tonsil. In addition, some areas in the jaws also showed accumulation. CONCLUSIONS: In patients with oral cancers, areas of (18)F-FDG accumulation in the oral cavity should be precisely identified and appropriately diagnosed, because accumulations can be seen in areas other than the primary tumour.

Distinct effects of cevimeline and pilocarpine on salivary mechanisms, cardiovascular response and thirst sensation in rats.

OBJECTIVE: Cevimeline and pilocarpine (muscarinic receptor agonists) are used as sialogogues in xerostomia treatment. It is important to know the different effects on their salivary mechanisms and the side effects. The aim of the present study was to clarify and compare the comprehensive effects of cevimeline to pilocarpine on salivary, cardiovascular and central mechanisms in rats. DESIGN: Under anaesthesia, whole saliva secretion, parotid blood flow and blood pressure were measured following intra-peritoneal administrations of the sialogogues. In digested parotid cells, intracellular Ca(2+) concentrations were measured after the sialogogue application. In the conscious condition, changes in angiotensin II-induced water intake were observed after cevimeline administration. In the subfornical organ, which is a thirst-related central nucleus, the effect of cevimeline on the neuronal activity was electrophysiologically investigated. RESULTS: Cevimeline at 80µmolkg(-1) showed slowly increasing and lasting salivation, a similar blood flow increment in the parotid gland and higher pressor response when compared to pilocarpine at 4µmolkg(-1). In parotid cells, cevimeline increased the intracellular Ca(2+) concentration in a similar manner to pilocarpine, but at a higher concentration than pilocarpine. Cevimeline inhibited angiotensin II-induced water intake and neuronal activity in the subfornical organ, which is in contrast to reported effects of pilocarpine. CONCLUSIONS: Cevimeline activates common salivary mechanism with pilocarpine but has a slower onset of activation, longer duration of salivation and an increased pressor response at higher doses. The anti-dipsogenic effect of cevimeline is due to the inhibitory neuronal effect on the thirst-related central nuclei.