Type II thyroplasty changes cortical activation in patients with spasmodic dysphonia.

OBJECTIVE: Spasmodic dysphonia (SD) is a complex neurological communication disorder characterized by a choked, strain-strangled vocal quality with voice stoppages in phonation. Its symptoms are exacerbated by situations where communication failures are anticipated, and reduced when talking with animals or small children. Symptoms are also reduced following selected forms of treatment. It is reasonable to assume that surgical alteration reducing symptoms would also alter brain activity, though demonstration of such a phenomenon has not been documented. The objective of this study is to reveal brain activity of SD patients before and after surgical treatment. METHODS: We performed lateralization thyroplasties on three adductor SD patients and compared pre- and post-operative positron emission tomography recordings made during vocalization. RESULTS: Pre-operatively, cordal supplementary motor area (SMA), bilateral auditory association areas, and thalamus were activated while reading aloud. Such activity was not observed in normal subjects. Type II thyroplasty was performed according to Isshiki's method and the strained voice was significantly reduced or eliminated in all three patients. Post-operative PET showed normal brain activation pattern with a significant decrease in cordal SMA, bilateral auditory association areas and thalamus, and a significant increase in rostral SMA compared with pre-operative recordings. CONCLUSION: This is the first report showing that treatment to a peripheral organ, which reverses voice symptoms, also reverses dysfunctional patterns of the central nervous system in patients with SD.

A case of floppy epiglottis in adult: a simple surgical remedy.

A new operative technique for the treatment of floppy epiglottis is introduced in this report. Though its diagnosis is not so difficult by close observations using a flexible fiberscope, it is likely to be treated as an asthma attack or a paradoxical vocal cord movement. In previous reports of upper airway obstruction caused by adult floppy epiglottis: epiglottis prolapse during inspiration, the cause of this condition has been divided broadly into two categories: idiopathic cases and secondary cases. Partial or total epiglottectomy has been usually reported for the treatment of the relief of airway obstruction caused by a floppy epiglottis. It is very difficult to decide adequately how much volume of epiglottis to cut without postoperative sequelae. A V-shaped partial epiglottidectomy is described for its treatment. This technique is very easy, simple, and effective.

A case report of myasthenia gravis localized to the larynx.

This report describes a very rare case of myasthenia gravis (MG) localized to the larynx, with the onset of dyspnea requiring tracheotomy. The vocal cords of this patient were fixed in the paramedian position. Under fiberscopic observation, improvement of laryngeal function was demonstrated after intravenous injection of edrophonium. However, no voice change occurred. The posterior crico-arytenoid muscle has the sole responsibility of abducting the vocal cord; thus, it is concluded that the dyspnea was caused by the selective paralysis of this muscle. We suggest that MG should be considered in cases of vocal cord paralysis of unknown etiology.

Hyperfractionated radiotherapy for T2 glottic cancer for preservation of the larynx.

To evaluate the effectiveness of hyperfractionation for T2 glottic cancer from a viewpoint of laryngeal preservation, we analyzed 21 patients (twice-a-day group) who were treated with hyperfractionation between 1992 and 1998 and compared the results with those of 27 patients (once-a-day group) treated with conventional once-a-day radiation between 1987 and 1992. In the twice-a-day group, radiation was performed with two fractions of 1.2 Gy/day up to a total dose of 72-74.4 Gy. In the once-a-day group, radiation was performed with a fraction of 2 Gy/day up to a total dose of 66 Gy. If radiation was ineffective at 40 Gy, it was stopped, and surgical treatment was carried out. Kaplan-Meier estimates were used for the analysis of the survival rate and laryngeal preservation rate, and the results were compared. In the once-a-day group, the 5-year survival rate was 92.3%. The 5-year laryngeal preservation rate was 51.8%, and it was 60.3% in 20 patients who had undergone full-dose radiation (once-a-day full-dose group). In the twice-a-day group, no major complication, such as laryngeal necrosis, was seen in any case, and the 5-year survival rate was 95.3%. The 5-year laryngeal preservation rate was 95.3%, and it was significantly better than that of both the once-a-day group and the once-a-day full-dose group. Hyperfractionation is considered to be useful for preserving the larynx for the treatment of T2 glottic cancer.

Steroid injection to vocal nodules using fiberoptic laryngeal surgery under topical anesthesia.

Since 1990, we have performed steroid injection into the vocal fold by fiberoptic laryngeal surgery (FLS) under local anesthesia. In this study, the usefulness of this method was evaluated in 28 patients with vocal nodules. Under monitoring using a fiberoptic laryngoscope, a curved injection needle was inserted via the oral cavity and steroid was injected. Endoscopic findings showed that the vocal nodule had disappeared in 17 patients of the 27 patients and decreased in 10 after injection. The maximum phonation time was 10.9 s before operation and 13.9 s after operation, showing a significant increase (P<0.05), and the mean flow rate also showed a significant improvement (P<0.05). The patients self-rating concerning hoarseness demonstrated great improvement after injection. This technique can be performed under local anesthesia in combination with voice therapy on an outpatient basis, and it is considered to be useful for treating vocal nodules.

Cricoid regeneration using in situ tissue engineering in canine larynx for the treatment of subglottic stenosis.

The purpose of the present study was to evaluate the efficacy of cricoid regeneration via in situ tissue engineering in a canine larynx for the treatment of subglottic stenosis. As the tissue scaffold, a Marlex mesh tube coated by collagen sponge was used for a rigid airway framework and for tissue regrowth around the tube. On 5 dogs, the larynx was exposed and the anterior third of the cricoid cartilage was resected. The tube was anastomosed to the lower edge of the thyroid cartilage and to the first tracheal cartilage. By postoperative endoscopic examination at 3 to 7 months, no airway obstruction was observed in any of the dogs. There was granulation tissue in 2 dogs and slight mesh exposure in 1 dog, but they were asymptomatic. Confluent regeneration of the epithelium over the scaffold and good incorporation of the scaffold mesh into the host tissue were observed after surgery.

Regeneration of the vocal fold using autologous mesenchymal stem cells.

The aim of this study was to regenerate the injured vocal fold by means of selective cultured autologous mesenchymal stem cells (MSCs). Eight adult beagle dogs were used for this experiment. Selective incubation of MSCs from bone marrow was done. These MSCs were submitted to 3-dimensional incubation in 1% hydrochloric acid atelocollagen. Three-dimensional incubated MSCs were injected into the left vocal fold, and atelocollagen only was injected into the right vocal fold of the same dog as a control. Four days after injection, the posterior parts of the vocal folds were incised. The regeneration of the vocal fold was estimated by morphological and histologic evaluations. Our results showed that 3-dimensional incubated MSCs were useful in the regeneration of the injured vocal fold. This study shows that damaged tissues such as an injured vocal fold would be able to be regenerated by tissue engineering.

Recurrent laryngeal nerve regeneration by tissue engineering.

The recurrent laryngeal nerve (RLN) does not regenerate well after it has been cut, and no current surgical methods achieve functional regeneration. Here, we evaluate the functional regeneration of the RLN after reconstruction using a biodegradable nerve conduit or an autologous nerve graft. The nerve conduit was made of a polyglycolic acid (PGA) tube coated with collagen. A 10-mm gap in the resected nerve was bridged by a PGA tube in 6 adult beagle dogs (group 1) and by an autologous nerve graft in 3 dogs (group 2). Fiberscopic observation revealed functional regeneration of the RLN in 4 of the 6 dogs in group 1. No regeneration of the RLN was observed in any dog in group 2. We also tested for axonal transport, and measured the compound muscle action potential. The RLN can be functionally regenerated with a PGA tube, which may act as a scaffold for the growth of regenerating axons.

Steroid injection for Reinke's edema using fiberoptic laryngeal surgery.

OBJECTIVE: Since 1990, we have performed steroid injections into the vocal fold under topical anesthesia using fiberoptic laryngeal surgery (FLS) in an outpatient clinic. The aim of this study was to retrospectively assess the usefulness of this treatment method in 44 patients with mild Reinke's edema. MATERIAL AND METHODS: Using fiberoptic monitoring of the larynx, a curved injection needle was inserted via the oral cavity and triamcinolone acetonide was injected into Reinke's space of the bilateral vocal fold. RESULTS: Remission or improvement was observed in almost all patients in terms of both patients' self-rating of hoarseness and endoscopic vocal fold findings The maximum phonation time was a mean of 9.0 s before operation and 11.4 safter operation, and this increase was significant (p < 0.01). Voice pitch also improved, from 168 to 181 Hz, in female patients, and this increase was also significant (p < 0.05). CONCLUSION: Steroid injection is considered to be useful for treating mild Reinke's edema.

Inner ear hearing loss modulates ipsilateral temporal lobe activation by monaural speech stimuli.

We examined cortical activation by speech in patients with moderate inner ear hearing loss using PET to investigate the response of the language network to insufficient speech input. We made two word lists, well-perceived words and poorly-perceived words, and measured rCBF during monaural presentation of these words. Well-perceived words activated bilateral temporal lobes, bilateral inferior frontal gyri (IFG) and left angular gyrus (AG) regardless of the ear stimulated, Poorly-perceived words activated contralateral temporal lobe and bilateral IFG, while little or no activation was observed in the ipsilateral temporal lobe and left AG. Insufficient activation of the temporal lobe ipsilateral to the ear stimulated might correlated with less accurate word comprehension in patients with inner ear hearing loss.

Descending necrotizing mediastinitis following acute epiglottitis: a case report.

Descending necrotizing mediastinitis occurs secondary to deep neck infection, and the primary focus of infection is mostly located in the tonsil, pharynx and carious tooth. DNM following acute epiglottitis is quite rare, with only one case reported. We treated an 84-year old female with an acute epiglottitis followed by DNM. She was successfully treated by drainages with cervical surgery combined with thoracotomy and cervical surgery.

Fiberoptic laryngeal surgery for vocal process granuloma.

We developed a technique of fiberoptic laryngeal surgery for the treatment of vocal process granulomas. In this system, the granuloma can be removed relatively easily and repeatedly under topical anesthesia on an outpatient basis. We treated 27 patients for a total of 4 intubation granulomas and 23 contact granulomas. Ten of the 23 contact granulomas recurred after the initial surgery, but the intubation granulomas did not recur. Most of the recurrent lesions were resolved by fewer than 3 procedures, and all patients were finally cured. Although conservative therapies such as voice therapy and proton pump inhibitors have recently prevailed, surgical removal remains useful in treating vocal process granulomas. Fiberoptic laryngeal surgery facilitates repeated surgical procedures.

Left Hemispheric Dominance and the Role of Verbal Motor-Related Region in Language Cognition.

This paper discusses the cortical processing of speech recognition and the vocalization function from the results of previous PET studies, and speculates that the neuronal network encompassing the right ear, the left auditory area, and the cerebellum is engaged in accurate cognition of acquired speech, and the network of the left ear, right auditory area, and the supplementary motor area (SMA) is contributed to analyzing unknown language. A system of categorized word sounds may exist in the cerebellum, for the comparison and inspection of sound stimuli, which facilitates accurate and prompt cognition. On the other hand, for unknown speech sound, the SMA may propagate categorization of the sound input by analyzing the pattern of vocalization action.