[One-port video-assisted thoracic surgery for pneumothorax using mini loop retractor].

We successfully performed 1-port video-assisted thoracic surgery (VATS) for primary spontaneous pneumothorax using Mini Loop Retractor II in 137 (39%) of 351 patients from March 2005 to May 2009 at Tokyo Teishin Hospital. This retractor is accessible to the thoracic cavity by simple skin puncture. It can hold and retract the lung freely like forceps. We made a 2 cm incision and inserted a 5 mm thoracoscope. We held the affected lung by the retractor and performed wedge resection by endoscopic staplers through skin incision. The operation time was 34.8 +/- 10.9 minutes and the blood loss was trace level in all cases. The duration of chest drainage was 1.2 +/- 0.8 days and the postoperative hospital stay was 2.8 +/- 1.2 days. There was no major complications. The recurrence of pneumothorax was noted in 17 (12.4%) cases. One-port VATS for pneumothorax using Mini Loop Retractor II can be applied easily and safely to selected patients.

Plasma brain natriuretic peptide concentrations in patients undergoing pulmonary vein isolation.

OBJECTIVE: To examine whether raised plasma brain natriuretic peptide (BNP) concentrations decrease after successful pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). METHODS: 53 patients (mean age 53 years) with drug-refractory, paroxysmal lone AF underwent segmental ostial PVI. Blood samples were collected before and after PVI. BNP concentrations were determined by immunoassays. RESULTS: Median plasma BNP concentrations were significantly higher in patients with lone AF than in controls (patients with supraventricular tachyarrhythmias, n = 21) (64.6 (71.9) v 13.9 (7.8) pg/ml, p < 0.01). AF recurred in 21 patients after the initial PVI procedure (recurrent AF group), and the others were free from AF without antiarrhythmic drugs (non-recurrent AF group). BNP concentrations were significantly decreased by PVI in the non-recurrent AF group (38.9 (39.1) to 18.3 (16.1) pg/ml, p < 0.01) but not in the recurrent AF group. CONCLUSIONS: Raised plasma BNP concentrations decreased after successful segmental ostial PVI in patients with AF.

[Thoracoscopic resection for Mycobacterium avium complex].

We report 2 cases of thoracoscopic resection for patients with Mycobacterium avium complex (MAC). A 25-year-old female was referred to our hospital because of abnormal shadows in the right lower lung field on chest X-ray. Her chest computed tomography (CT) showed that the lesion was localized in the right lower lobe. She was given a diagnosis of MAC by polymerase chain reaction (PCR) of sputum. Thoracoscopic lobectomy was performed after chemotherapy for 10 months. A 64-year-old female was referred to our hospital because of hemoptysis. Bronchiectasis had been diagnosed in her since the age of 35 years, and then she was given a diagnosis of secondary MAC. Her chest CT showed bronchiectasis, and consolidations were localized in the superior segment of the right lower lobe. Then superior segmentectomy of the right lower lobe under video-assisted thoracoscopic surgery (VATS) was performed. It was reported that surgical intervention is indicated in patients with MAC, when persistent hemoptysis is seen or chemotherapy is ineffective. If the lesion is localized, lung resection under VATS may be a good option in selected patients.

[Intraoperative complications of thoracoscopic surgery for mediastinal tumors].

We report intraoperative complications of thoracoscopic surgery for mediastinal tumors. Forty cases of mediastinal tumor were undergone thoracoscopic surgery at the hospital from 1999 to 2002. The patient's ages ranged from 18 to 74 years old with a mean of 47.7. Location of these tumors were anteriormediastinal in 20 cases, middlemediastinal in 6 cases, posteriormediastinal in 11 cases, and superiormediastinal in 3 cases. Intraoperative complications were rupture of the cyst in 9 cases, bleeding over 150 ml in 5 cases, injury of lung caused by adhesiolysis in 5 cases, and injury of nerve in 3 cases. The mean operation time was 103.8 minutes. Postoperative hospital stay ranged from 2 to 22 days with a mean of 5.9 days. All are alive with no recurrences or postoperative complications.

[Case report of surgically treated dumbbell-type schwannoma arising in the right brachial plexus with von Recklinghausen disease].

We encountered a patient with dumbbell-type schwannoma arising in the right brachial plexus with von Recklinghausen disease. The patient was a 9-year-old girl. An abnormal shadow was detected high in the thoracic cavity by thoracic radiography. Thoracic CT and MRI demonstrated at the apex of the thoracic cavity a tumor measuring 9.0 x 6.0 cm, which was diagnosed as a dumbbell-type neurogenic tumor derived from the brachial plexus. Most cases of such tumors growing inside and outside the spinal cavity have reportedly been treated in a single surgical procedure. However, since the tumor in this patient was large, the intrathoracic portion was removed first in order to minimize the magnitude of the surgical invasion. The residual intraspinal tumor was removed during subsequent surgery. No neurological problems were observed after surgery. Patients with dumbbell-type schwannomas arising in the right brachial plexus appear to be very rare, and this patient was considered noteworthy.

Prussak's space: chronological development and routes of aeration.

Investigation of Prussak's space and its relationship to adjacent spaces is important in elucidating the cause of retraction pocket and cholesteatoma formation in this space. This study was designed to quantitatively characterize the chronological development of Prussak's space and its relationship to adjacent spaces in temporal bones. One-hundred and forty-nine human temporal bone slides (115 normal, 28 with otitis media with effusion, three with retraction pockets and three with attic type cholesteatoma) including specimens ranging from fetal to adult bones were studied. Prussak's space was formed and sufficient aeration routes established by 4 years of age in normal temporal bones. In temporal bones with otitis media with effusion, however, the growth of Prussak's space was suppressed and few routes for aeration established until 10 years of age. In normal temporal bones, Prussak's space developed with aeration routes sufficient to avert the negative pressure which can result in retraction pocket formation in the pars flaccida of the tympanic membrane.

[Prognosis of the surgical treatment for non-Hodgkin lymphoma originating from chronic tuberculous empyema--analysis of 11 cases with pleuropneumonectomy].

In total 19 cases of non-Hodgkin lymphoma originating from the wall of chronic tuberculous empyema, pleuropneumonectomeic were performed since 1979, with the aim of total cures for not only lymphoma but empyema in 11 cases. Of these cases extraresections (5 of thoracic cages, 4 of diaphragms, 2 of axillar lymph nodes, each of adventitia of descending aorta and esophagus, of the liver, of the left adrenal grand) were added to extirpate tumors completely. The mean operating time was 6 degrees 55', the mean blood loss during operations was 3090 ml, but in the 3 most recent cases it was less than under 1000 ml using electrocartesy-cutting technique under direct observation. Although preoperative radiations were done to 4 cases to decrease invasive area of tumors and postoperative radiation was done to 1 case, there were no adjuvant chemotherapies. The indicative limitation for resections from the point of ventilatory functions was the same as that of pleuropneumonectomy for ordinary chronic tuberculous empyema. There were 2 cases with serious postoperative complications. One suffered from ARDS and died on the 14th postoperative day, and another developed acute respiratory failure and MOF. But the other 9 cases kept good postoperative courses with a few recurrences of minor empyema. The prognoses for 10 remaining cases is excellent. Only one case died from local recurrence in of lymphoma 27 months later, but all other 9 cases have revealed no recurrence in any places, and the 5 year survival rate based on Kaplan-Meier method of 10 cases is 85.7%. By the way no cases could survive one year later in unresected group. So under the poor prognosis of treatment with radiation or chemotherapy for non-Hodgkin lymphoma originating from chronic tuberculous empyema, we conclude that the complete resection of tumor and empyema, so called pleuropneumonectomy, is the best way to cure this disease.

Tl-201 SPECT in Kimura's disease involving the parotid glands and cervical nodes.

Kimura's disease is a chronic inflammatory condition producing subcutaneous tumor-like nodules, mainly in the head and neck region. Most patients have involvement of regional lymph nodes and major salivary glands. The authors present two cases of Kimura's disease with parotid gland and postauricular lymph node involvement. With Tl-201 SPECT, elevated uptake was noted on early and delayed images. Kimura's disease should be included in the differential diagnosis when increased Tl-201 uptake in head and neck mass lesions is noted.

Improvement of the surgical technique of anterior tympanoplasty in cholesteatoma.

Technical improvements in anterior tympanotomy with a transmastoid approach in cholesteatoma surgery are reported. Mastoidectomy must be extended to the root of the zygoma and the space anterior to the malleus head must be opened. For this purpose, the visual axis must coincide with the external meatal axis. In this head position, complete removal of the anterior attic bony plate becomes possible only through the transmastoid approach, without touching the ossicular chain. In the case of the pyramidal type bony plate with a normal ossicular chain, the incudo-malleal joint is temporary subluxated, as this is more convenient for access and removal of pathology than incudostapedial joint subluxation. Our clinical results on postoperative hearing showed no damage to the inner ear by the improved technique.

Generation of a phase-conjugate wave by degenerate four-wave mixing in an erythrosin-B-doped planar waveguide.

A phase-conjugate wave (PCW) generated by degenerate four-wave mixing (DFWM) in a nonlinear-optical waveguide excited by a cw Ar-ion laser was observed. The planar waveguide consisted of a transparent polyvinyl alcohol layer partly doped with erythrosin-B. The DFWM excitation was performed as follows: Two pump waves impinged in the interaction region of the waveguide from the outside, and a probe wave was introduced into the guiding layer by a prism coupler. A PCW reflectivity of 6.3 x 10(-5) outside the prism coupler was obtained at a pump intensity of 1.2 W/cm(2).

Computed tomographic evaluation of middle ear aeration following intact canal wall tympanoplasty.

The condition of the mastoidectomy cavity following intact canal wall tympanoplasty (ICWT) is always of great interest to the otosurgeon. We evaluated the status of postoperative aeration in a stable ear following ICWT for various types of chronic otitis media using high-resolution computed tomography (CT). The mastoidectomy cavity in all the cases of simple suppurative otitis is totally aerated and that in over 60% of the cases of adhesive otitis, attic type cholesteatoma and adhesive type cholesteatoma is obliterated by a soft tissue density mass. The size of aerated spaces in the postoperative middle ear cavity not only depends on the type of chronic otitis media but also tends to correlate with the degree of mastoid pneumatization in the opposite ear. CT is useful for the postoperative assessment of middle ear aeration.

Intensity profile of outgoing beams from uniform and linearly tapered grating couplers.

Intensity distribution of outgoing beams from a uniform sinusoidal grating is investigated on the basis of first-order perturbation theory by dividing the grating region into short subsections. Intensity distribution of outgoing beams from a linearly tapered sinusoidal grating is also studied by considering it as a chain of uniform gratings with steplike amplitudes and using the results obtained for the uniform grating. The intensity profile of outgoing beams from a uniform grating coupler is theoretically verified to exhibit an extremely asymmetric shape and to differ considerably from the Gaussian shape laser beam usually employed as an incident beam in an input coupler, although this fact has been well recognized by people who have studied gratings. However, the output intensity beam profiles from the linearly tapered grating are found to approach a Gaussian shape similar to the profile of the incident beam.