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991.
Raynaud's phenomenon is a currently vascular syndrome (8 to 10% of women and 3 to 5% of men). It was defined as episodic ischaemia of the fingers, toes, nose, ears and nipples, which presents clinically as pallor, cyanosis, and often rubor of the skins, in response to cold, emotional stimuli and vasoconstriction agents. The phenomenon is caused by a vasoconstriction of arterials skin. In severe forms of the phenomenon, we can see ulcerations and necrosis. We report here two cases of rhytidectomy flap necrosis in Raynaud's Phenomenon. After review of literature, we explain the elements of physiopathology whose can explain these complications and we try to establish recommendations to these complications.  相似文献   
992.
Our aim was to determine the influence of antibiotic treatment using ceftriaxone on [18F]-fluorodeoxyglucose (FDG) uptake in experimental soft tissue infections. PET scans were performed in two groups (treated n=4; non-treated n=4) at days 3, 5, and 6 after inoculation of the infection. Additional autoradiography was performed in four animals at day 7 and in three animals at day 11. The difference of FDG uptake on day 5 (after three days of antibiotic treatment) between both groups proved to be significant (df=6; T=2.52; p=0.045). FDG uptake determined at the other days did not reveal significant difference between the two groups. It seems to be possible that the effect of antibiotic treatment on FDG uptake is less evident than reported for therapy monitoring of cancer treatment. The change of FDG uptake over time in treated and untreated infections is complex and further in vivo experiments have to be initiated to investigate the potential value of clinical FDG PET in therapy monitoring of infection.  相似文献   
993.
PURPOSE: To evaluate imaging characteristics and artifacts of a nitinol stent with distal tantalum markers with computed tomography (CT) angiography and magnetic resonance (MR) angiography. MATERIALS AND METHODS: A vascular phantom was built to simulate in-stent restenosis. A nitinol stent with tantalum markers (Luminexx stent) was evaluated with CT angiography in different orientations relative to the z-axis and with MR angiography in different positions relative to both B0 and the readout gradient. Stenosis measurements were compared with conventional digital subtraction angiography for both modalities. In-stent signal intensity obtained with different flip angles was assessed in two nitinol stents with distal markers (Luminexx stent and SMART stent) and one without markers (Memotherm-FLEXX stent). RESULTS: Stenosis detection was not possible with CT angiography when the stent was perpendicular to the z-axis because of streak-like artifacts induced by tantalum markers. Stenosis evaluation with multiplanar reformation was accurate when the stent was in parallel and oblique orientations relative to the table axis. With MR angiography, metallic artifacts were mostly related to the stent orientation with B0, whereas orientation of the readout gradient had little influence. The mean error (overestimation) for stenosis measurements varied between 0.1% and 7.4% for CT imaging in parallel and oblique positions and 3.6% and 9.5% for MR imaging. Higher flip angles did not improve signal intensity inside the three stents tested. CONCLUSION: CT and MR angiography can be used for evaluating the patency of stents with distal markers that are parallel or oblique relative to the table axis (iliac, carotid, or femoral stents). MR angiography is preferred if the stent is perpendicular to the table axis (renal stent).  相似文献   
994.
995.
OBJECT: Gamma knife surgery (GKS) has emerged as a suitable treatment of pharmacologically resistant idiopathic trigeminal neuralgia. The optimal radiation dose and target for this therapy, however, remain to be defined. The authors analyzed the results of GKS in which a high dose of radiation and a distal target was used, to determine the best parameters for this treatment. METHODS: The authors evaluated results in 47 patients who were treated with this approach. All patients underwent clinical and magnetic resonance imaging examinations at 6 weeks, 6 months, and 1 year post-GKS. Fifteen potential prognostic factors associated with favorable pain control were studied. The mean follow-up period was 16 months (range 6-42 months). The initial pain relief was excellent (100% pain control) in 32 patients, good (90-99% pain control) in seven patients, fair (50-89% pain control) in three patients, and poor (< 50% pain control) in five patients. The actuarial curve of pain relief displayed a 59% rate of excellent pain control and a 71% excellent or good pain control at 42 months after radiosurgery. Radiosurgery-induced facial numbness was bothersome for two patients and mild for 18 patients. Three prognostic factors were found to be statistically significant factors for successful pain relief: a shorter distance between the target and the brainstem, a higher radiation dose delivered to the brainstem, and the development of a facial sensory disturbance after radiosurgery. CONCLUSIONS: To optimize pain control and minimize complications of this therapy, we recommend that the nerve be targeted at a distance of 5 to 8 mm from the brainstem.  相似文献   
996.

Purpose

Most children and adults with blunt splenic injuries are treated nonoperatively by well-established management protocols. The “blush sign” is an active pooling of contrast material within or around the spleen seen during intravenous enhanced computed tomography (CT) scan. Adult treatment algorithms often include the “blush sign” as an indication for embolization or surgical intervention. This study was designed to evaluate the implications of the “blush sign” in children with blunt splenic injuries.

Methods

A review was performed of all children with blunt splenic injuries treated between January 1996 and December 2001 at a level I pediatric trauma center using an established solid organ injury protocol. The demographic, CT imaging, and outcome data were recorded. Treatment was categorized as operative or nonoperative. A single pediatric radiologist retrospectively reviewed all available CT scans to confirm injury grade and the presence or absence of a “blush sign.”

Results

There were 133 eligible children admitted with blunt splenic trauma, with a mean age of 9.1 years (range, 1 to 15), including 86 children with an abdominal CT available for review. A “blush sign” on initial CT scan was noted in 6 children, all with grade 3 or above splenic injuries, 5 of who were treated nonoperatively. In this series, the single child with a “blush sign” who did not respond to nonoperative treatment had a severe polytrauma requiring urgent splenectomy and left nephrectomy. None of the children died of their splenic injury.

Conclusions

Although associated with higher grades of injury, the blush sign did not mandate embolization or surgical intervention in children with blunt splenic trauma in this series. Severe splenic injuries with a blush sign on the initial CT scan may be successfully treated nonoperatively when using an established treatment protocol. Management should be based primarily on physiological response to injury rather than the radiologic features of the injury.  相似文献   
997.
Nance ML  Lutz N  Carr MC  Canning DA  Stafford PW 《The Journal of trauma》2004,57(3):474-8; discussion 478
BACKGROUND: Nonoperative management of radiographically defined solid organ injuries has proven highly successful in children with blunt splenic and hepatic injuries. The role of nonoperative management protocols is less well defined for blunt renal injuries. The purpose of this study was to review the management and outcome of a consecutive series of children with blunt renal injury. METHODS: The trauma registry from a Level I pediatric trauma center was reviewed to identify all children (age < 19 years) who were treated for a blunt renal injury for the period January 1995 through December 2002. Demographic, anatomic, physiologic, management, and outcome data were analyzed. RESULTS: For the 8 years of review, 101 children with a blunt renal injury were identified, including 95 with accessible and complete data. The renal injury population had a mean age of 10.4 years (range, 0.5-18 years) and was 72.6% male. The renal injuries were distributed as follows: grade 1, n = 22; grade 2, n = 40; grade 3, n = 20; grade 4, n = 11; and grade 5, n = 2. Hematuria was present in 88.1% of children (in whom urinalysis results were available). Four children had underlying congenital renal anomalies. The mean hospital length of stay and intensive care unit stay were 6.0 and 2.6 days, respectively. Overall, 5 children (5.3%) required laparotomy, including 1 nephrectomy (isolated grade 4 injury) and 1 renorrhaphy, for an overall renal salvage rate of 98.9%. In children with isolated renal injuries (n = 48), one child (2.1%) required laparotomy. Seven children required adjunctive urologic procedures (ureteral stenting, n = 5; cystoscopy/cystogram, n = 2). There were seven deaths (7.4% overall; five because of head injury and two because of severe abdominal bleeding at presentation). CONCLUSION: A nonoperative management strategy was advantageous and successful in pediatric blunt renal injuries (94.7% successful nonoperative rate, 98.9% renal salvage rate). Adjunctive urologic procedures (e.g., ureteral stenting) were beneficial in selected cases.  相似文献   
998.
999.
1000.
A long duration of acute retroviral syndrome (ARS) and a short incubation of ARS (IncARS) are independent predictors of a fast progression to AIDS. The first objective of this study was to validate previous estimates of IncARS by comparing durations between health care workers (HCWs) accidentally infected by HIV and individuals infected by other routes (non-health care workers [N-HCWs]). The second objective was to use parametric survival models to generate hypotheses on various steps occurring during the IncARS. Data from a prospective cohort of patients with documented ARS and from individuals with ARS as the result of accidental exposure to HIV were analyzed. Nonparametric and parametric survival models were used to describe the incubation of ARS. No differences were found for the median IncARS between 34 HCWs (21.5 days) and 70 N-HCWs (21.5 days) (log-rank test, P = 0.72). According to survival models, IncARS can be modeled with a gamma and/or lognormal model with means of 26.4 days and 26.7 days, respectively. The gamma model suggests that 3 sequential stages are present during the IncARS, which is compatible with basic science investigations identifying crossing of the epithelial barrier by the virus, the virus-host cell interactions, and the viral systemic dissemination.  相似文献   
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