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81.
In August 1997, a 68-year-old man presented with right pelvic pain. Pelvic computed tomography (CT) and bone scintigraphy showed a huge tumor of the right iliac bone. No other lesion was detected, in spite of a high serum carcinoembryonic antigen level (CEA, 963ng/ml). In October 1997, the iliac bone tumor was widely resected, and thereafter was diagnosed to be a metastatic adenocarcinoma of unknown origin. After a resection, the serum CEA level dropped as low as 6.4ng/ml, but gradually went up to 80ng/ml in October 1999. Next, a lung tumor in the left upper lobe was detected by routine chest CT. In January 2000, a left upper lobectomy was performed, and based on not only the pathological findings but also on an immunohistochemical analysis for napsin A expression, the tumor was diagnosed to be lung adenocarcinoma. The histological and immunohistochemical findings in the previously resected bone lesion were completely compatible with those in the pulmonary tumor, which was finally regarded as M1 lung cancer. In October 2002, the patient was alive without any symptoms, although the serum CEA level was elevated again. We consider this case worthy of presentation because of its unique clinical course as well as the successful long-term survival after surgical treatment alone, for both the primary and metastatic lesions.  相似文献   
82.
A 42-year-old obese woman with a history of liver cirrhosis and diabetes mellitus was admitted because of chest pain. Coronary balloon angioplasty and stenting were performed on the left anterior descending artery (LAD), which was 90% stenotic. She developed moderate shock about 6h later, and about 15 h after the procedure, she died from excessive bleeding from the right femoral artery because of removal of the catheter sheath by herself. Autopsy disclosed haemorrhagic cardiac tamponade and extensive haemorrhage into the epicardial adipose tissue, however, neither coronary perforation nor myocardial rupture was recognized. Histological examination of the dilated coronary segment revealed extensive dissection with an eccentric intimal thickening and the disruption of the adventitia. It was thought to be the origin of the haemorrhage. Although coronary dissection is a well-known complication during cardiac catheterization procedures, this report describes a rare fatal case with delayed onset of shock due to coronary dissection caused by balloon angioplasty and stenting in the presence of eccentric hyperplasia of the vessel wall.  相似文献   
83.
Adjacent segment disease after anterior cervical interbody fusion   总被引:11,自引:0,他引:11  
BACKGROUND CONTEXT: There have been many follow-up studies on anterior interbody fusion for cervical nerve root and spinal cord compression, and excellent neurological outcomes have been reported. However, postoperative degenerative changes at adjacent discs may lead to the development of new radiculopathy or myelopathy. In the previous reports, the incidence of symptomatic adjacent segment disease has ranged from 7% to 15%. PURPOSE: The present study was undertaken to investigate the incidence of symptomatic adjacent segment disease after anterior cervical interbody fusion (ACIF) and to identify the factors that are related to the development of this disease. STUDY DESIGN/SETTING: This is a retrospective cohort study. PATIENT SAMPLE: A total of 112 patients were followed up clinically and radiologically for more than 2 years. OUTCOME MEASURES: Follow-up evaluation was primarily by means of clinical visits. The postoperative course of any symptoms, the findings of neurological examination and serial follow-up radiographs were performed in all patients. METHODS: The diagnosis of symptomatic adjacent segment disease was based on the presence of new radiculopathy or myelopathy symptoms referable to an adjacent level, and the presence of a compressive lesion at an adjacent level by magnetic resonance imaging or myelography. We evaluated the correlation between the incidence of symptomatic adjacent segment disease and the following clinical parameters (age at operation, sex, number of the levels fused) and radiological parameters (preoperative cervical spine alignment, preoperative range of motion of C2-C7 cervical spine, anteroposterior spinal canal diameter, preoperative existence of an adjacent segment degeneration on plain radiograph, myelography and magnetic resonance imaging [MRI]). RESULTS: Symptomatic adjacent segment disease developed in 19 of 112 patients (19%) followed. A Kaplan-Meier survival analysis was performed in order to follow the disease-free survival of the entire series of patients. The disease-free survival rates were 89% at 5 years, 84% at 10 years and 67% at 17 years. The incidences of indentation of dura matter on preoperative myelography or disc protrusion on MRI at the adjacent level were significantly higher in disease cases (p=.0087, .0299, respectively; chi-squared test). However, the other parameters did not show a statistically significant difference. There were seven cases (37%) who had failure of nonoperative treatment and additional operations were performed. CONCLUSIONS: The incidence of symptomatic adjacent segment disease after ACIF was higher when preoperative myelography or MRI revealed asymptomatic disc degeneration at that level regardless of the number of the levels fused, preoperative alignment, spinal canal diameter or fusion alignment.  相似文献   
84.
The cerebellum is a crucial structure for cognitive function as well as motor control. Benign brain tumors such as schwannomas, meningiomas, and epidermoids tend to occur in the cerebellopontine angle cisterns and may cause compression of the posterior lateral cerebellum near the superior posterior fissure, where the eloquent area for cognitive function was recently identified. The present study examined cognitive impairment in patients with benign cerebellar tumors before and after surgical intervention in order to clarify the functional implications of this region in humans. Patients with cerebellar tumors showed deficits in psychomotor speed and working memory compared with healthy controls. Moreover, these impairments were more pronounced in patients with right cerebellar tumors. Functional magnetic resonance imaging during performance of a lure task also demonstrated that cerebellar tumors affected pattern separation or the ability to distinguish similar experiences of episodic memory or events with discrete, non-overlapping representations, which is one of the important cognitive functions related to the hippocampus. The present findings indicate that compression of the human posterior lateral cerebellum affects hippocampal memory function.  相似文献   
85.
Transmesenteric hernia is a rare cause of bowel obstruction in adults. We herein describe two cases that occurred in adult women, ages 27 and 19. Both cases presented with abdominal pain without muscular defense signs. Computed tomography of both cases showed features of small bowel obstruction by an internal hernia. A laparotomy showed mesenteric defects of the mesentery of the ileum in the former case and the mesentery of the transverse colon in the latter case, with a herniating ileum. The involved small bowel was viable in both cases, and the bowel was pulled out of the mesenteric defect without resection. The mesenteric defects were then successfully repaired.  相似文献   
86.

Background

Robot-assisted and laparoscopic partial nephrectomies (PNs) for medial tumors are technically challenging even with the hilum clamped and, until now, were impossible to perform with the hilum unclamped.

Objective

Evaluate whether targeted vascular microdissection (VMD) of renal artery branches allows zero-ischemia PN to be performed even for challenging medial tumors.

Design, setting, and participants

A prospective cohort evaluation of 44 patients with renal masses who underwent robot-assisted or laparoscopic zero-ischemia PN either with anatomic VMD (group 1; n = 22) or without anatomic VMD (group 2; n = 22) performed by a single surgeon from April 2010 to January 2011.

Intervention

Zero-ischemia PN with VMD incorporates four maneuvers: (1) preoperative computed tomographic reconstruction of renal arterial branch anatomy, (2) anatomic dissection of targeted, tumor-specific tertiary or higher-order renal arterial branches, (3) neurosurgical aneurysm microsurgical bulldog clamp(s) for superselective tumor devascularization, and (4) transient, controlled reduction of blood pressure, if necessary.

Measurements

Baseline, perioperative, and postoperative data were collected prospectively.

Results and limitations

Group 1 tumors were larger (4.3 vs 2.6 cm; p = 0.011), were more often hilar (41% vs 9%; p = 0.09), were medial (59% and 23%; p = 0.017), were closer to the hilum (1.46 vs 3.26 cm; p = 0.0002), and had a lower C index score (2.1 vs 3.9; p = 0.004) and higher RENAL nephrometry scores (7.7 vs 6.2; p = 0.013). Despite greater complexity, no group 1 tumor required hilar clamping, and perioperative outcomes were similar to those of group 2: operating room time (4.7 and 4.1 h), median blood loss (200 and 100 ml), surgical margins for cancer (all negative), major complications (0% and 9%), and minor complications (18% and 14%). The median serum creatinine level was similar 2 mo postoperatively (1.2 and 1.3 mg/dl). The study was limited by the relatively small sample size.

Conclusions

Anatomic targeted dissection and superselective control of tumor-specific renal arterial branches facilitate zero-ischemia PN. Even challenging medial and hilar tumors can be excised without hilar clamping. Global surgical renal ischemia has been eliminated for most patients undergoing PN at our institution.  相似文献   
87.
Zero-ischemia robotic and laparoscopic partial nephrectomy, a novel concept, eliminates ischemia to the tumor-free normal kidney. Anatomic microdissection of tertiary/higher-order tumor-specific arteries is performed to selectively devascularize only the tumor, maintaining normal perfusion of the remaining kidney. A thorough understanding of renovascular tumor anatomy is essential. Based on 0.5-mm-slice thickness computed tomography scans, we developed a novel three-dimensional (3D) reconstruction technique that fuses three key anatomic aspects: surface-rendered tumor, semitransparent kidney, and extra- and intrarenal arterial anatomy. Four central completely intrarenal hilar masses underwent 3D reconstruction for surgical navigation during zero-ischemia partial nephrectomy. Negative surgical margins were obtained in all four cases, with no intraoperative complications or transfusions. For these challenging laparoscopically invisible masses, 3D image navigation precisely identified tumor-specific arterial branches, thus facilitating zero-ischemia partial nephrectomy without hilar cross clamping.  相似文献   
88.
The prevalence of coronary artery disease in patients with aortic aneurysm is high. As an antecedent percutaneous coronary intervention with antiplatelet therapy may cause a rupture of aortic aneurysm, concomitant treatment for aortic arch aneurysm and coronary artery disease is recommended. We report a technique of a combined procedure of antegrade endovascular repair with aortic arch debranching and off-pump coronary artery bypass grafting.  相似文献   
89.
Background: The study hypothesizes that nitrous oxide (N2O) releases opioid peptide in the brain stem, which results in inhibition of [gamma]-aminobutyric acid-mediated (GABAergic) neurons that tonically inhibit the descending noradrenergic inhibitory neurons (DNIN), resulting in activation of DNIN. In the spinal cord, activation of DNIN leads to the release of norepinephrine, which inhibits nociceptive processing through direct activation of [alpha]2 adrenoceptor and indirect activation of GABAergic neurons through [alpha]1 adrenoceptor. Arising from this hypothesis, it follows that GABAergic neurons will modulate the antinociceptive effect of N2O in diametrically opposite directions at supraspinal and spinal levels. The authors have tested this tenet and further examined the effect of midazolam, a GABA-mimetic agent, on N2O-induced antinociceptive effect.

Methods: Adult male Fischer rats were administered muscimol (GABAA receptor agonist) intracerebroventricularly (icv), gabazine (GABAA receptor antagonist) intrathecally (intrathecal), or midazolam intraperitoneally (intraperitoneal). Fifteen minutes later, they were exposed to air or 75% N2O and were subjected to the plantar test after 30 min of gas exposure. In some animals administered with midazolam, gas exposure was continued for 90 min, and the brain and spinal cord were examined immunohistochemically.

Results: The N2O-induced antinociceptive effect, which was attenuated by icv muscimol, intrathecal gabazine, and intraperitoneal midazolam. Midazolam inhibited N2O-induced c-Fos expression (a marker of neuronal activation) in the pontine A7 and spinal cord.  相似文献   

90.
BACKGROUND: Tissue factor (TF) expression is induced on macrophages and endothelial cells during the immune response. We designed an antisense (AS) phosphorothioate oligodeoxynucleotide (ODN) to specifically inhibit the expression of rat TF to study the effects of the AS ODN on renal ischemia-reperfusion injury in the rat. METHOD: AS-1 ODN for TF was delivered intravenously to inhibit the expression of TF in endothelial cells. After 8 hr, the right kidney was harvested and the left renal artery and vein were clamped. The kidney was reperfused after 90 min of ischemia, and rats were killed at 0, 1.5, 5, 12, and 24 hr after reperfusion. TF expression was analyzed by immunohistochemical staining using monoclonal antibody. RESULTS: In the untreated ischemic group, 0 of 20 rats survived beyond day 3. However, treatment with AS-1/TF led to 12 of 20 rats surviving beyond day 4. TF was detected on distal tubular epithelial cells, endothelial cells, and blood vessels but not on necrotic and proximal tubular epithelial cells. The necrotic area extended and encompassed nearly all of the ischemic kidney within 12 hr after reperfusion. The necrotic area and the grade of TF staining were more significantly reduced in the AS-1/TF-treated group than in the control group. Furthermore, fluorescein isothiocyanate-labeled AS-1/TF was significantly intense in tubular epithelial cells 8 hr after intravenous administration. CONCLUSIONS: The results indicate that AS-1/TF inhibited the ischemia-reperfusion injury of the kidney. Microcirculatory incompetence resulting from microthrombus may cause the formation and development of necrosis.  相似文献   
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