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991.
BACKGROUND: Percutaneous endoscopic gastrostomy is the standard for long-term enteral access. It can provide enteral nutrition or gastrointestinal decompression. Utilization of the gastrostomy for decompression has traditionally been reported in the setting of malignant obstruction. However, decompressive gastrostomy can play a role in the treatment of nonmalignant bowel dysfunction as well. METHODS: Over a 2-year period, 20 of 121 percutaneous endoscopic gastrostomies attempted by this surgical endoscopist were for gastrointestinal decompression. RESULTS: Eleven of 18 gastrostomies successfully placed for decompression were for benign conditions. In 5 patients with fistulous disease, the purpose of decompression was to divert the gastrointestinal tract until operative repair. Four of these patients have since undergone definitive surgery. CONCLUSIONS: This series presents the successful use of the percutaneous endoscopic gastrostomy for decompression of nonmalignant conditions. In such scenarios, the drainage gastrostomy can be employed as a bridge to future surgery, or as a means of long-term decompression for bowel dysfunction. 相似文献
992.
Nitric oxide synthase in acute alteration of nitric oxide levels after subarachnoid hemorrhage 总被引:5,自引:0,他引:5
Sehba FA Chereshnev I Maayani S Friedrich V Bederson JB 《Neurosurgery》2004,55(3):671-7; discussion 677-8
OBJECTIVE: Subarachnoid hemorrhage (SAH) is associated with acute decreases and subsequent recovery of cerebral nitric oxide (NO) levels, but the mechanisms of these alterations are not known. In this study, we measured NO synthase (NOS) protein and kinetics to determine its involvement in the alterations of cerebral NO levels after SAH. METHODS: The endovascular rat model of SAH was used. The number of NOS-1 (neuronal) and NOS-2 (inducible)-positive cells (0-96 h) was determined by counting immunoreactive cells in 8-microm cryostat sections. The tissue content of active NOS and its kinetic parameters were studied with an enzymatic l-citrulline assay. RESULTS: The number of NOS-1-positive cells increased between 1 and 3 hours after SAH, decreased to and below control values at 6 and 72 hours after SAH, and increased to control values 96 hours after SAH. The number of NOS-2-positive cells increased 1 hour after SAH, decreased to control values at 24 hours, and increased above control values 96 hours after SAH. The Michaelis-Menten kinetic parameters (V(max), K(m), slope) of NOS remained unchanged at 10 and 90 minutes after SAH. CONCLUSION: NOS-1 and -2 proteins undergo a triphasic alteration after SAH, whereas the amount of active NOS and its kinetic parameters remain unchanged during the first 90 minutes after SAH. Depletion of NOS is not involved in the acute alterations of cerebral NO levels after SAH. 相似文献
993.
OBJECTIVE AND IMPORTANCE: Radiation vasculopathy and radionecrosis, constituting delayed radiation injury, are rare but recognized complications of radiation therapy occurring at a peak incidence of 3 years after treatment. Little information is available about these complications occurring more than 15 years after radiotherapy and presenting as other than solid intracranial masses. CLINICAL PRESENTATION: We describe two patients who presented with space-occupying cerebral lesions. Patient 1 presented as an emergency with a sudden loss of consciousness. Computed tomography revealed a large left intracerebral hemorrhage; cerebral angiography disclosed nothing abnormal, and a primary spontaneous hemorrhage was presumed. Twenty-seven years earlier, this patient had received adjuvant whole-brain and spine radiotherapy and concomitant chemotherapy after excision of a vermis medulloblastoma. Patient 2 presented with a left frontal cystic lesion (presumed malignant glioma) as the cause of personality and behavioral changes for some months. She had previously received external beam radiation for a basal cell epithelioma, which had been excised from her left forehead 19 years earlier. INTERVENTION: Both patients recovered well after undergoing craniotomies and removal of their lesions; they were discharged home with no neurological deficit. CONCLUSION: Even after long intervals after radiotherapy, it is important to consider radiation vasculopathy and radionecrosis as differential diagnoses of more common conditions. Histological confirmation of a delayed radiation injury in the absence of any evidence of neoplasia or vascular abnormality has allowed appropriate prognosis and management to be formulated with confidence in each of these patients. 相似文献
994.
Laser and novel light source treatments for psoriasis 总被引:1,自引:0,他引:1
BACKGROUND AND OBJECTIVES: There are many treatment modalities for psoriasis including topical therapy, ultraviolet light therapy, systemic agents, and more recently the advent of the biologic agents. STUDY DESIGN/MATERIALS AND METHODS: In addition, selective treatment using lasers and light sources that target the individual psoriatic plaques have also been employed. RESULTS/CONCLUSION: This article will highlight and review the employment of laser-assisted devices in the treatment of plaque psoriasis. 相似文献
995.
Although Levine and Drennan described the metaphyseal-diaphyseal angle (MDA) in tibia vara using the lateral border of the tibial cortex, there is a lack of uniformity in the literature. The authors measured the MDA using both the lateral border and the center of the tibial shaft in 132 knees (66 patients) with bowleg deformity and examined whether there is a significant difference between these two measurements. At angles < or =11 degrees there was significant variance between the two methods. At angles >11 degrees, there was excellent correlation between the two methods and no statistical difference between the two methods. The authors conclude that either method of defining the longitudinal axis is acceptable to measure the MDA for the diagnosis and monitoring of tibia vara. 相似文献
996.
997.
998.
Liu JK Tenner MS Gottfried ON Stevens EA Rosenow JM Madan N MacDonald JD Kestle JR Couldwell WT 《Journal of neurosurgery》2004,100(3):414-421
OBJECT: Cerebral vasospasm that is caused by aneurysmal subarachnoid hemorrhage and that is refractory to maximal medical management can be treated with selective intraarterial papaverine infusions. The effects of single papaverine treatments on cerebral circulation time are well known. The purpose of this study was to assess the efficacy of multiple, repeated papaverine infusions on the cerebral circulation time in patients with recurrent vasospasm. METHODS: A retrospective study was conducted in 17 patients who received multiple intraarterial papaverine infusions in 91 carotid artery (CA) territories for the treatment of cerebral vasospasm. Cerebral circulation times were measured from the first angiographic image, in which peak contrast was seen above the supraclinoid internal CA, to the peak filling of cortical veins. Glasgow Outcome Scale (GOS) scores assessed 12 months after discharge were reviewed. Cerebral circulation times in 16 CA territories were measured in a control group of 11 patients. Seventeen patients received a total of 91 papaverine treatments. Prolonged cerebral circulation times improved after 90 (99%) of 91 papaverine treatments. The prepapaverine mean cerebral circulation time was 6.54 seconds (range 3.35-27 seconds) and the immediate postpapaverine mean cerebral circulation time was 4.19 seconds (range 2.1-12.6 seconds), an overall mean decrease of 2.35 seconds (36%, p < 0.001). Recurrent vasospasm reflected by prolonged cerebral circulation times continued to improve with subsequent papaverine infusions. Repeated infusions were just as successful quantitatively as the primary treatment (mean change 2.06 seconds). The mean cerebral circulation time in the control group was 5.21 seconds (range 4-6.8 seconds). In five patients a dramatic reversal of low-attenuation changes was detected on computerized tomography scans. The mean GOS score at 12 months after discharge was 3.4. CONCLUSIONS: The preliminary results indicate that multiple intraarterial papaverine treatments consistently improve cerebral circulation times, even with repeated infusions in cases of recurrent vasospasm. 相似文献
999.
While most BK virus infections are asymptomatic, immunosuppression has been associated with BK virus reactivation and impaired graft function or ureteric ulceration in renal transplant patients and hemorrhagic cystitis in bone marrow transplant patients. Oncogenicity is also postulated and this is the first report of a child with a carcinoma of the donor renal pelvis following BK virus allograft nephropathy. Removal of the primary tumor and cessation of immunosuppression led to regression of secondary tumors and a return to health. 相似文献
1000.
Anemia in pediatric renal transplant recipients 总被引:2,自引:2,他引:0
The aim of this study was to establish the prevalence of anemia in stable pediatric renal transplant recipients and to examine the association of anemia with renal function, immunosuppressants, angiotensin converting enzyme inhibitors, and growth, as well as iron, vitamin B12, and folate stores. This is a cross-sectional study of the 50 renal transplant recipients currently followed at our center. Patient data were collected regarding hematological parameters, growth, medications, renal function, underlying renal disease, delayed graft function, episodes of rejection, and iron or erythropoietin therapy post transplantation. The mean hemoglobin level (Hb) was 110 g/l and the overall prevalence of anemia was 60%, including 30% who were severely anemic (Hb<100 g/l). There was a high rate of iron deficiency (34%) and serum iron was the parameter of iron metabolism most closely associated with anemia. Hb in patients with low serum iron was 90.7 g/l versus 114.4 g/l in those with normal serum iron (P<0.01). Both univariate and multiple linear regression determined tacrolimus dose and creatinine clearance to be significant factors associated with anemia. Tacrolimus dose correlated with a 10 g/l reduction in Hb for every increase of tacrolimus dose of 0.054 mg/kg per day (P=0.001). The dose of mycophenolate was positively correlated with Hb, but this was likely to be confounded by our practice of dose reduction in the setting of anemia. Angiotensin converting enzyme inhibitor use was not associated with anemia. Severely anemic patients tended to be shorter, with a mean Z-score for height of –1.8 compared with –0.9 for those with normal Hb (P=0.02). Anemia is a significant and common problem in pediatric renal transplant patients. Deteriorating renal function is an important cause, but other factors like iron deficiency and immunosuppression are involved. Definition of iron deficiency is difficult and serum iron may be a valuable indicator. Medication doses, nutritional status, need for erythropoietin and iron, as well as poor graft function and growth require systematic scrutiny in the care of the anemic renal transplant recipient. 相似文献