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41.
Background: T1-shortening contrast media are routinely used in magnetic resonance (MR) examinations for the diagnosis of brain tumors. Although some studies show a benefit of 3 Tesla (T) compared to 1.5T in delineation of brain tumors using contrast media, it is unclear which pulse sequences are optimal.

Purpose: To compare gadopentetate dimeglumine (Gd-DTPA)-induced signal enhancements in rat brain C6 glioma in the thalamus region among different pulse sequences in 3T MR imaging.

Material and Methods: Five rats with a surgically implanted C6 glioma in their thalamus were examined. T1-weighted brain images of the five rats were acquired before and after Gd-DTPA administration (0.1 mmol/kg) using three clinically available pulse sequences (spin echo [SE], fast SE [FSE], fast spoiled gradient echo [FSPGR]) at 3T. Signal enhancement in the glioma (ET) was calculated as the signal intensity after Gd-DTPA administration scaled by that before administration. Pulse sequences were compared using the Tukey-Kramer test.

Results: ET was 1.12±0.05 for FSE, 1.26±0.11 for FSPGR, and 1.20±0.11 for SE. FSPGR showed significantly higher signal enhancement than FSE and comparable enhancement to SE.

Conclusion: FSPGR is superior to FSE and comparable to SE in its ability to delineate rat brain C6 glioma in the thalamus region.  相似文献   
42.
Metastatic prostate cancer (PC) is incurable by androgen deprivation therapy alone, due to the presence of androgen-independent/supersensitive cells in hormone-naive PC. A 67-year-old man was diagnosed with PC (Gleason score, 5 + 4) with multiple bone metastases. He was treated by chemohormonal therapy with cisplatin and estramustine phosphate (EMP) followed by maximal androgen blockade, and showed a complete response. As of the time of writing, no clinical or prostate-specific antigen recurrence has been observed for over 15 years, despite cessation of the treatment. This is the first report to indicate a possible cure of metastatic PC by chemohormonal therapy combined with appropriate anti-tumor drugs targeted to both androgen-independent and -dependent clones before the hormone-refractory state.  相似文献   
43.
Off-pump coronary artery bypass grafting (CABG) [OPCAB] or on-pump beating CABG (conventional CABG) was performed in 3 post-thoracoplasty patients. Considering their poor respiratory function after thoracoplasty, OPCAB is considered more suitable than conventional CABG with cardio-pulmonary bypass in such cases with severe coronary lesions. However, because the sternum inclines or the pleural cavity may be polluted in these patients, special care is necessary for the operation. In such cases, it may be impossible to bypass to the circumflex artery in OPCAB, and is necessary to consider the use of percutaneous cardiopulmonary support (PCPS), cardio-pulmonary bypass or hybrid therapy before the operation.  相似文献   
44.
Tracheal chondrosarcomas are rare, with only 14 cases previously documented. We report a case of chondrosarcoma of the trachea and review other published cases. Our patient was a 34-year-old man who began to feel shortness of breath 8 months after initial hemoptysis. Transverse and coronal computed tomography demonstrated a tumor that was obstructing nearly 80% of the tracheal lumen at the thoracic inlet. A bronchoscopic biopsy specimen led to an initial diagnosis of chondroma. Five tracheal rings from the third to the seventh including the tumor were completely resected, and an end-to-end anastomosis was performed. The histological diagnosis of the surgical specimen showed it to be a chondrosarcoma. The patient was alive without recurrence at 6 years 4 months after surgery. Because recurrence after incomplete resection and malignant transformation can occur with chondromas, radical resection of the trachea is recommended for all cartilaginous tumors of the trachea.  相似文献   
45.
BACKGROUND: Video-assisted thoracoscopic surgery (VATS) has become an attractive surgical procedure, but several issues remain to be resolved. Prognosis after VATS lobectomy is important to evaluate the adequacy of VATS lobectomy as a cancer operation. Interestingly, several investigators, including us, have reported that prognosis after VATS lobectomy was superior to that after open lobectomy in early non-small-cell lung cancer (NSCLC). One of the possible reasons is the low invasiveness of VATS lobectomy. But we considered that patient bias might have some influence favoring VATS lobectomy. To evaluate our hypothesis, we reviewed medical records of stage I NSCLC patients undergoing operation between 1993 and 2002. We compared and evaluated the relationship between patient characteristics and prognosis after VATS and open lobectomy. We focused particularly on histological type, classifying it into four subgroups; (1) bronchioloalveolar carcinoma (BAC), (2) mixed BAC + papillary adenocarcinoma (BAC + Pap), (3) other adenocarcinoma (Other adeno), (4) squamous cell carcinoma + others (Sq + others). RESULTS: A total of 165 patients underwent VATS lobectomy, and 123 patients underwent open lobectomy. The 5-year survival rate of the VATS lobectomy group was 94.5% and that of the open lobectomy group was 81.5%. Univariate Cox regression of survival revealed that male, CEA > 5, Other adeno, Sq + others, open lobectomy, and tumor size > 3 cm were significant negative prognostic variables. Multivariate Cox regression of survival revealed that histological subtype and tumor size were independent prognostic factors, but surgical procedure was not an independent prognostic factor. COMMENTS: Prognosis after VATS lobectomy was superior to that after open lobectomy, but patient bias influenced the prognosis in favor of VATS lobectomy, and the surgical procedure itself was not a prognostic factor.  相似文献   
46.
BACKGROUND: Vasospasm is a frequent complication in the early clinical course after SAH. Although various methods have been used to measure cerebral perfusion including PET, SPECT, xenon CT, and TCD, these require the patients to remain still for a long period. In addition, TCD is operator dependent. The current study aimed to clarify the convenience of CTP for the assessment of cerebral vasospasm caused by SAH. METHODS: Nineteen patients with SAH aged 44 to 85 years (mean, 64 years) were recruited with informed consent. All patients were treated with the prevailing therapy and underwent CTP on days 6 to 9, followed by DSA and 3D-CTA to detect cerebral vasospasm. In each patient, we measured the MTT, CBF, and CBV. The reliability of CTP data was verified by comparing the data from CTP and xenon CT between the controls, and the average was calculated. Six ROIs were located symmetrically in the frontal, temporal, and occipital lobes. RESULTS: An MTT value more than 20% greater than the average indicated the progression of cerebral vasospasm, and patients with vasospasm-related infarcts exhibited an MTT more than 47% greater than the mean value (odds ratio, 50). Patients with delayed cerebral infarcts had a significantly lower mean CBF and CBV and higher MTT than patients who did not develop CI. CONCLUSION: Significant correlations between MTT and CBF values and neurovascular findings were obtained. Computed tomography perfusion can be performed in a short time and on a regular basis, and it therefore has the potential to identify cerebral vasospasm because of SAH.  相似文献   
47.
We have devised a medial peri-articular osteotomy, the distal tibial oblique osteotomy (DTOO), and have used this technique since 1994 for ankle osteoarthritis of advanced and late stages associated with varus inclination. This report describes the surgical technique and its applicability. DTOO can be used for cases of varus ankle osteoarthritis with a range of the ankle joint movement of at least 10° or more. The osteotomy is obliquely directed cut across the distal tibia from proximal-medial to distal lateral and is of an opening-wedge type with the centre of rotation coincident with the centre of the tibiofibular joint. A laminar spreader instrument is inserted in the osteotomy to open the wedge until the lateral surface of the talar body is seen on X-ray to be in contact and congruent with medial articular surface of the lateral malleolus. Common obstacles which may prevent this contact and congruency are bony spurs present on the anterior side of fibula or on the lateral side of the tibia; these require removal. The opening-wedge osteotomy is held in position by an Ilizarov external fixator or internally fixed with a plate. Bone graft is taken from the iliac crest and inserted into the open wedge. If, after completion of the osteotomy, the dorsiflexion angle of the ankle joint does not exceed 0°, a Z-lengthening is performed of the Achilles tendon. In the DTOO for ankle osteoarthritis, the contact area of the ankle joint increases and decreases the load pressure per unit area. Furthermore, as the width of the ankle mortice is restored through the realignment of the body of the talus, instability at the ankle joint decreases. There is additional improvement with restoration of the inclination of the distal tibial articular surface as this directs the hindfoot valgus and corrects the alignment of the foot, with consequent improvement of ankle pain.  相似文献   
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A case of iatrogenic intracranial artery dissection is reported. A 52-year-old female developed severe headache and nausea. Brain CT showed diffuse subarachnoid hemorrhage. On admission, carotid angiography revealed an aneurysm in the right middle cerebral artery and the intact right internal carotid artery. The aneurysm was clipped successfully. Carotid angiography on day 7 revealed dissection in the right internal carotid artery. Repeated angiograms at 10 and 31 days showed progression of the carotid artery dissection. Findings of ECD-SPECT on day 31 (Balloon occlusion test) suggested low perfusion of the right internal carotid artery territory. The patient underwent surgical reconstruction of the right internal carotid artery using a radial artery. She presented with right abducens nerve palsy three days after the radial artery graft. The patency of the radial artery graft was proved by the post-operative angiography. Internal carotid artery dissection may occur spontaneously or as a result of trauma. An iatrogenic dissection is an uncommon complication of cerebral angiography. There are no evidence-based guidelines for the treatment although anticoagulation therapy is most commonly used. The present case emphasizes the usefulness of radial artery graft for traumatic carotid artery dissection.  相似文献   
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