Hiroshi Ohkubo

Recurrent Laryngeal Nerve Paralysis. A 10-Year Review of 564 Patients

A retrospective review of the clinical records of 564 patients with recurrent laryngeal nerve paralysis examined at the Department of Otolaryngology, Kurume University Hospital during the 10-year period from 1971 to 1980 was completed. The results are summarized as follows: 1) Two-hundred and ninety-three patients were male and 271, female. The incidence was high in old age groups. 2) Idiopathic paralysis (233 cases) was the most frequent and paralysis caused by thyroid surgery (68 cases) and endotracheal intubation (63 cases) came next. 3) The lesion was unilateral in 519 patients (right to left = 148 to 371) and bilateral in 45. 4) The paralytic vocal fold was fixed in the paramedian position in the majority of the patients. A limited movement of the paralytic fold was observed in some cases, especially those of paralysis caused by endotracheal intubation and idiopathic paralysis. 5) A compensatory overcrossing of the unaffected vocal fold was found in 41 patients. It developed within six months from the onset in most cases. 6) Spontaneous recovery and improvement of mobility took place in 54 of the 165 patients who could be followed up for 1 year or longer. Paralysis caused by endotracheal intubation showed the best prognosis and idiopathic paralysis came next. 7) Spontaneous voice recovery and improvement occurred in 183 of the 240 patients whose voice outcome was determined. 8) Phonosurgical treatments yielded good results in most cases. Some patients, however, had their voice receded later.

CO2 Laser in Treating Carcinoma of the Tongue

Since 1980, we have been using CO2 laser in treating carcinomas of the tongue. Carcinomas confined to the mucosa have been treated with laser excision alone. Five patients were treated in this way and they are all alive with no evidence of disease. Follow-up ranges from 11 months to 3 years. Carcinomas with a superficial muscular invasion have been treated with mass reduction laser surgery followed by chemoradiotherapy. There were 19 patients which fell in this category. Of these 19, 17 are alive with no evidence of disease, 1 died of an intercurrent disease, and 1 died of cervical metastasis. Follow-up ranges from 9 months to 5 years and 1 month. For carcinomas with a deep muscular invasion, we first attempted an induction chemotherapy consisting of cisplatin and pepleomycin. When the chemotherapy was effective, we applied mass reduction laser surgery followed by chemoradiotherapy. Two patients were treated in this way. One is alive with no evidence of disease (11-month follow-up) whereas the other died of pulmonary metastasis. Following the treatments using laser, speech intelligibility is much better than after extensive surgeries.

Anisotropy of Jc, Hc2 and flux pinning in c-axis oriented epitaxial YBa2Cu3O7 thin film

Abstract Anisotropic properties of orientation dependence of Jc and Hc2 for a c-axis oriented epitaxial YBa2Cu3O7 thin film have been studied in three kinds of configurations of magnetic field H, transport current I and c-axis in H up to 12 T. In the case of H ⊥ c-axis it is found that at the temperature ∼ 77 K and in the low field region (H⩽3 T), no obvious Lorentz force type influence on Jc is observed, while when H is increased to ∼ 7 T, Jc is influenced by the Lorentz force rather distinctly. On the other hand, in the case that H is oriented between the c-axis and a-b plane, Jc is sensitive to whether H is perpendicular to I or not, but it is quite sensitive to the angle ϕ between H and c-axis, in particular, in the case of ϕ > 60°. Further, at each angle ϕ, H- and T- dependences of Jc show that Jc is not simply affected by the Lorentz force, but through the action of the flux creep type effect.

Flux creep in c-axis oriented epitaxial YBa2Cu3O7 thin film

A systematic study of the flux creep behavior has been carried out for c-axis oriented epitaxial YBa2Cu3O7 thin films based on the Anderson and Kim flux creep model. In a wide magnetic field (H) range (0 to 12 T) and temperature (T) range (10 to 82 K), the behavior of the critical current density J(c), the flux bundle (size upsilon-d and jump distance l) and resistive transiton broadening DELTA-T(c) have been investigated. It is found that J(c)(H, T) fairly well obeys the frame of flux creep model in the above temperature range; in a certain low-field region (less-than-or-similar-to 1 T), a relation of upsilon-d proportional H-1 is found; in the high (H, T) region, upsilon-d(l) shows an anomalous behavior which is discused in terms of the decomposition of the flux bundle. It is also found that the relation of DELTA-T(c) porportional H-2/H-3 exists in all field orientation against the c-axis, but the slope of DELTA-T(c) versus H-2/H-3 depends strongly on orientation.

Surface Acoustic Waves in High-Tc Superconducting Thin Films on Piezoelectric PbTiO3 Films

To generate surface acoustic waves (SAW) and to fabricate substrates for superconducting Bi-compound film, piezoelectric PbTiO3 films with preferred c-axis orientation were prepared on MgO (100) substrates by the rf-sputtering method. By using an interdigital electrode fabricated on PbTiO3 film for generation and detection of SAW, it has been confirmed that SAW with the frequency of 192 MHz are propagated on PbTiO3 film/MgO substrate, as-deposited Bi-compound film/PbTiO3/MgO substrate and heat-treated superconducting Bi-compound film/PbTiO3/MgO substrate. The temperature dependence of the SAW attenuation coefficient has been investigated below room temperature in detail, especially in the neighborhood of the superconducting transition temperature, and found to exhibit almost monotonic decreasing behavior with decreasing temperature.

Aquired laryngo-pharyngeal fistula

Acquired laryngo-pharyngeal fistula is a very rare condition. This paper reports a 65-year-old man who presented with a laryngo-pharyngeal fistula caused by trauma to the cervical vertebra. The symptom was persistent aspiration. The fistula was located between the subglottic space and the hypopharynx through the cricoid lamina. A fluoroscopic video recording was useful in demonstrating the fistula, and a fibrescopic examination confirmed its existence and exact location. The fistula was successfully treated with closure of both larynx and pharynx with a sternomastoid muscle interposition.

Non-Specific Granuloma of the Larynx. A 10-Year Review of 63 Patients

During the 10 years from 1971 to 1980, 63 cases of non-specific granuloma of the larynx were examined at the Department of Otolaryngology, Kurume University Hospital. Of the entire 63 cases, 51 were intubation granulomas, 5, contact granulomas and 7, granulomas of unknown etiology. A review of the clinical records of these patients was completed. The results are summarized as follows; 1) In intubation granulomas, there was a significant preponderance of females over males (43 to 8). The age ranged from 9 to 72 years. The lesion was bilateral in 21 cases and unilateral in 30. All the granulomas but one were located at the cartilaginous portion. Twenty-one (75%) of the 28 cases which were surgically treated got healed, 6 (21%) developed a recurrence and 1 was lost to follow up. 2) All 5 patients with contact granulomas were males. Their lesions were unilateral. Three patients were surgically treated. Two of these 3 had no recurrence while the other developed a recurrence, which disappeared following conservative treatments. One patient was successfully treated with conservative modalities. 3) Granulomas of unknown etiology were found in 5 males and 2 females. Their age ranged from 19 to 70 years. The lesion was unilateral in all 7 cases. Three patients were surgically treated. Two of these 3 required repeated surgeries. One patient was successfully treated by means of conservative therapy.

Surface acoustic waves in high-Tc superconducting thin films

Piezoelectric PbTiO3 films with preferred c-axis orientation were fabricated on MgO substrates by RF-sputtering method. By using a fabricated interdigital electrode, surface acoustic waves (SAWs) with a frequency of 192 MHz were propagated on PbTiO3 film/MgO substrate and on superconducting Bi(Pb)2Sr2Ca2Cu2Oy film/PbTiO3/MgO substrate. The temperature dependence of the SAW attenuation coefficient was investigated below room temperature.

A Phase Shift Keying Communication System Using SAW Devices

A method is described for constructing a phase shift keying (PSK) system using surface acoustic wave (SAW) devices. The SAW device having three interdigital transducers, two for input and one for output, operates as the key element in the communication system. In the transmitting system, the device is used to generate a phase shift keyed rf signal corresponding to an input binary impulse train. The device is also requisite for synchronization and demodulation in the receiving system. A total communication system is demonstrated practically.

ANISOTROPY ON SUPERCONDUCTIVITY OF C-AXIS ORIENTED EPITAXIAL YBA2CU3O7 THIN-FILM

Abstract We have made a study of anisotropy in J c , H c 2 , flux pinning force ∫ p and resistive transition width ΔT c ( H ) of c-axis oriented epitaxial YBa 2 Cu 3 O 7 thin film. The systematic discussion was performed in combination with the flux creep model.