Kiminobu Sato

Comparative study of framework surgery and fat injection laryngoplasty

OBJECTIVE To evaluate differences between the functional results of framework surgery and autologous fat injection laryngoplasty, for patients with unilateral vocal fold paralysis. STUDY DESIGN Sixty-two patients underwent framework surgery, while 64 received autologous fat injection laryngoplasty. Voice function before and after both procedures was assessed using aerodynamic and acoustic analysis, with differences evaluated using paired t-test in both groups. RESULTS In both groups, all parameters improved significantly after surgery, compared with before surgery. Post-operative improvement in all parameters was significantly greater after fat injection laryngoplasty, compared with framework surgery. CONCLUSION Autologous fat injection laryngoplasty was thus found to be a more effective and reliable therapy for improving voice function in patients with vocal fold paralysis, compared with framework surgery.

Cultured stellate cells in human vocal fold mucosa

OBJECTIVES Stellate cells in the maculae flavae, located at both ends of the human vocal fold mucosa, have been considered an independent category of cells. We aimed to isolate and subculture these stellate cells, and to observe their morphological characteristics. METHODS Stellate cells from the maculae flavae and fibroblasts from Reinkes space were cultured in three normal, adult human vocal fold mucosa preparations. RESULTS The subcultured cells from Reinkes space were conventional fibroblasts. The subcultured cells from the maculae flavae were stellate in shape and had cytoplasmic processes. They were larger than conventional fibroblasts, and lipid droplets in the cytoplasm disappeared in the second culture. These stellate cells proliferated by attaching their cytoplasmic processes to each other. During the seven to 10 month subculture period, each cell type continued to exhibit its own morphological characteristics. CONCLUSION This study demonstrated that such stellate cells form an independent cell category, which should be considered as a new category of cells within the human vocal fold.

Tetra-probe, 24-hour pH monitoring for laryngopharyngeal reflux: a technique for simultaneous study of hypopharynx, oesophagus and stomach.

OBJECTIVE This study aimed to introduce the technique of tetra-probe, 24-hour pH monitoring for laryngopharyngeal reflux disease. METHODS Tetra-probe, 24-hour pH monitoring was performed for 30 suspected cases of laryngopharyngeal reflux. The proximal probe was placed in the hypopharynx, just above the upper oesophageal sphincter, the second probe was placed in the middle oesophagus, the third probe was placed a few centimetres above the lower oesophageal sphincter, and the distal probe was placed in the stomach. RESULTS As the pH at the four sensor sites could be monitored simultaneously, gastric acid levels and gastroesophageal and laryngopharyngeal reflux could be examined. This pH monitoring technique enabled the pH relationship between the four sensor locations to be well documented, enabling gastric acid levels and patterns of reflux to be assessed. This procedure was also able to be used as a functional examination to evaluate anti-reflux medication efficacy. CONCLUSIONS Tetra-probe, 24-hour pH monitoring is a reliable functional examination for laryngopharyngeal reflux.

Efficacy of autologous fat injection laryngoplasty with an adenoviral vector expressing hepatocyte growth factor in a canine model

OBJECTIVE The effectiveness of autologous fat injection laryngoplasty may be reduced by resorption of injected fat tissue. The aim of the present study was to clarify the efficacy of fat injection laryngoplasty using autologous fat plus a replication-defective adenoviral vector expressing hepatocyte growth factor, regarding reduction of injected fat tissue resorption. MATERIAL AND METHODS Four female beagle dogs were used in this study. After sedation, a direct laryngoscope was introduced to enable visualisation of the larynx. In each dog, harvested autologous fat plus an adenoviral vector expressing hepatocyte growth factor was injected into the right true vocal fold, and harvested fat plus an adenoviral vector expressing no gene was injected into the left true vocal fold. A total laryngectomy was performed one year after the intracordal fat injection. Coronal sections of the resected whole larynges were made and the following parameters assessed using light and electron microscopy: size of fat area; number of vasculoendothelial cells surrounding adipocytes; and shape of injected adipocytes in the vocal fold. RESULTS The fat area was significantly larger and the number of vasculoendothelial cells surrounding adipocytes significantly greater in the intracordal fat injection containing adenoviral vector expressing hepatocyte growth factor, compared with the control intracordal fat injection containing adenoviral vector expressing no gene. When viewed under electron microscopy, the injected adipocytes were observed to have grafted better in the intracordal fat injection with hepatocyte growth factor adenoviral vector, compared with the control intracordal fat injection with adenoviral vector expressing no gene. CONCLUSIONS Injection into the vocal fold of autologous fat containing an adenoviral vector expressing hepatocyte growth factor can reduce subsequent resorption of injected fat.

Histopathological study of correlation between laryngeal space invasion and lymph node metastasis in glottic carcinoma.

OBJECTIVES The paraglottic space and cricoid area of the larynx are made up of loose, areolar tissue composed of loose elastic and collagenous fibres and adipose tissue. They contain the main blood vessels of the larynx. We examined the correlation between the histopathological extension of glottic carcinoma into the paraglottic space or cricoid area and the development of cervical lymph node metastasis. STUDY DESIGN We reviewed the medical charts of 45 patients (44 men and one woman) who had undergone total laryngectomy for squamous cell carcinoma of the glottis between 1991 and 2003. METHODS Macroscopic and microscopic study of the removed larynges of the same patients was performed, and the histopathological evidence for invasion of the paraglottic space or cricoid area was analysed. RESULTS Eight of the 24 patients (33 per cent) with invasion of the paraglottic space or cricoid area had cervical lymph node metastasis. In contrast, only one of the 21 patients (5 per cent) without any evidence of invasion of either space had lymph node metastasis. This difference was statistically significant (p < 0.05). In the 36 patients free of cervical lymph node metastasis, recurrence in the neck occurred in six (38 per cent) of the 16 patients with paraglottic space or cricoid area invasion, but in only one (5 per cent) of the 20 patients without paraglottic space or cricoid area invasion (p < 0.05). CONCLUSION In patients with glottic carcinoma, invasion of cancer into the paraglottic space or cricoid area is an important prognostic factor for the development of cervical lymph node metastasis.

Local immune status and tumour marker expression in the human larynx.

This study examined the local immune status and tumour marker expression in secretions and related tissue specimens from the laryngeal ventricle, comparing individuals with and without head and neck cancer. Laryngeal secretion and mucosal tissue specimens were collected during laryngeal microsurgery or surgical laryngectomy. The laryngeal secretions were found to contain immunological factors such as immunoglobulins G and A and secretory immunoglobulin A. A high level of the tumour marker Cyfra 21-1 was also detected in laryngeal secretions and mucosal tissue. Lows levels of secretory immunoglobulin A and Cyfra 21-1 were seen in the laryngeal mucosal tissue of controls and patients who had previously undergone radiation therapy. The level of secretory immunoglobulin A in laryngeal secretions closely correlated to the level of this immunoglobulin in mucosal tissue. These results indicate that local immunity is present in the human larynx; furthermore, it is strongly affected both by the presence of malignancy and by laryngeal cancer treatments such as irradiation.

Mucoepidermoid carcinoma of the sublingual gland harboring a translocation of the MAML2 gene: A case report

Among tumors of the major salivary glands, tumors in the sublingual gland are rare. Although mucoepidermoid carcinoma (MEC) represents a histological type of salivary gland tumor, it is occasionally difficult to diagnose due to its histological variation. The present study reports a case of MEC harboring a mastermind-like transcriptional coactivator 2 (MAML2) gene translocation in the sublingual gland. A 76-year-old Japanese woman with a mass in the left submandibular region was referred to Kurume University Hospital (Kurume, Japan). Computed tomography scans revealed that the tumor was predominantly located in the sublingual gland, and tumor resection was performed. Histologically, the tumor was composed of cells that exhibited low-grade nuclear atypia and clear and/or granular eosinophilic cytoplasm, and that were proliferating in solid patterns. Periodic acid-Schiff and alcian blue staining revealed a small number of mucinous cells in the tumor. Immunohistochemically, the tumor cells were positive for p40 and p63. Fluorescence in situ hybridization (FISH) analysis revealed a MAML2 gene split. The definitive pathological diagnosis was low-grade MEC, as the case lacked any factors indicative of high-grade malignancy. To the best of our knowledge, this is the first report of MEC in the sublingual gland with MAML2 gene translocation confirmed by FISH.

Deglutition and respiratory patterns during sleep in the aged

Abstract Conclusion: Deglutition was extremely infrequent and displayed unique patterns during sleep in the aged. Objectives: The deglutition and respiratory phase patterns during sleep in the healthy aged were investigated in this study. Methods: Ten aged adults (average age = 71 years) were examined via time-matched digital recordings of polysomnography and surface electromyography of the muscles (thyrohyoid and suprahyoid muscles) related to swallowing. Results: During sleep, swallowing was extremely infrequent and absent for long periods in the aged. The median number of swallows per hour during total sleep time was 0.6, and the median longest deglutition-free period was 134.8 minutes. Most deglutition occurred in association with spontaneous electroencephalographic arousal both in REM and non-REM sleep. Deglutition was related to the sleep stage. The deeper the sleep stage, the lower the mean deglutition frequency. There was no deglutition during deep sleep. Overall muscle tone is inhibited during REM sleep. However, deglutition also occurred in association with spontaneous EEG arousal. The deeper the sleep stage, the lower the mean arousal frequency, and the lower the mean ratio of arousal with deglutition to arousal. Approximately one-third of swallows occurred after inspiration and were followed by inspiration.

Conservative treatment for recurrent dislocation of temporomandibular joint.

OBJECTIVE Recurrent dislocation of the temporomandibular joint is difficult to treat with nonsurgical methods. A new nonsurgical method for the treatment of this condition is presented. METHODS Routine dental arch bars were applied to the teeth, and two latex elastic bands were placed between the two arch bars on either side of the dental arch. Muscular exercises (i.e. active mouth opening) were then performed regularly over approximately three months. RESULTS Patients were followed up for two to five years, and the treatment proved successful in five of five cases (i.e. no recurrence was seen). The advantages of this treatment are its simplicity and the lack of special equipment needed. No surgery is required, although patients must perform regular muscular exercises. Surgical complications such as trismus and facial nerve palsy are avoided. The disadvantages of this method are the requirement for patient compliance, and its lack of usefulness in patients without teeth. CONCLUSIONS The described method is useful for patients complaining of recurrent dislocation of the temporomandibular joint.

Endoscopic sinus surgery for the anterior maxillary sinus, using a 135° reflective CO 2 laser

OBJECTIVES Endoscopic sinus surgery has been widely performed to treat nose and paranasal diseases. However, it is difficult to manipulate anterior wall lesions of the maxillary sinus using conventional surgical instruments. This paper presents a method of performing endoscopic surgery for anterior wall lesions of the maxillary sinus, using a 135 degrees reflective CO2 laser. METHOD A CO2 laser with a 135 degrees reflective tip on the pipe-guide handpiece and a CO2 laser angulated to the same degree were used. The pipe-guide handpiece with reflective tip was inserted into the nasal cavity and the base of the maxillary sinus anterior wall lesion was vaporised and removed via an enlarged natural ostium. During the procedure, the maxillary antrum was visualised with a 70 degrees endoscope. Ten cases of maxillary sinus anterior wall lesion underwent this surgical procedure. RESULTS In all cases, the base of the maxillary sinus anterior wall lesion was removed completely and recurrence avoided. CONCLUSION This method is a reliable procedure enabling endoscopic sinus surgery for anterior wall lesions of the maxillary sinus.