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71.

Background/Purpose

Perfusion imaging redefines computed tomography (CT) as a technique that can now depict vascular physiology in addition to detailed anatomy. The major clinical applications of perfusion CT are in acute stroke and oncology. Currently, there are very limited data on the application of perfusion CT in urology. The aim of the present study is to investigate the potential value of perfusion CT in anatomic and functional evaluation of obstruction in a single session on experimental hydronephrosis model in rats. Thus, we evaluate the perfusion CT in a new clinical application.

Methods

Twenty-eight rats were randomly allocated into 4 groups each consisting of 7 rats. At the third week of experimental intervention, postoperative renogram curves and perfusion parameters of the right kidneys' cortex and pelvis were assessed by CT. The right ureter was sutured as proximal complete obstruction in group 1, as distal complete obstruction in group 2, and as proximal partial obstruction in group 3. Group 4 served as the sham control group. Computed tomography was performed with single-slice tomography. Dynamic examination was performed with the help of perfusion software through contrast-enhanced tomography examination.

Results

In all study groups, the aorta time/density curves showed a rapid increase after a rapid decrease, and the duration to reach peak concentration in the normal kidney cortex was observed to be later than the aorta as expected. In groups 1, 2, and 3, the duration to reach peak concentration lengthened and the peak concentration values decreased. The time/density curves gradually increased as a result of the accumulation of the contrast agent in the pelvis, and a peak was observed at the end of the procedure in all study groups. In groups 1, 2, and 3, a statistically significant decrease (P = .01, P = .01, and P = .01, respectively) was observed in the peak concentration values of the contrast agent in comparison to group 4. The flow and blood volume values gradually decreased as the grade of the obstruction increased and the localization of the obstruction or grade of obstruction moved closer to the kidney.

Conclusion

In conclusion, perfusion CT technique, performed in a single session, is a useful method for anatomic visualization, together with functional evaluation, in the diagnosis of ureteric obstructive pathology of experimental hydronephrosis model.  相似文献   
72.
Suicide has been reported as the second or third most common cause of death in children and adolescents all over the world. The aim of the study was to investigate the general properties of suicide in childhood and adolescents, and to evaluate the results in the light of literature. Reports of autopsies performed between 2001 and 2005 in the Morgue Department of the Council of Forensic Medicine in Istanbul (n = 16853) were examined retrospectively. Deaths between 0–18 years of age doubtlessly considered as suicide were included in the study. Childhood and adolescent (0–18 years) deaths comprised 10.4% (n = 1761) of all medico-legal autopsy cases. 136 cases of suicidal origin were evaluated in terms of age, gender, and method of suicide. The ages ranged between 7 and 18, with a mean of 15.54 ± 2.691(SD). The most common method of suicide was hanging (59.2%) in both genders. Older adolescents (16–18 age group) constituted the overwhelming number (63.2%, n = 86) of all cases. Seven cases of 10 years of age and below were determined, and hanging was the method of suicide in five of these cases. In order to prevent childhood suicides, families and society should be aware of their responsibilities.  相似文献   
73.

Objective

To evaluate the added role of T1-weighted (T1w) gadolinium ethoxybenzyl diethylenetriamine penta-acetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance cholangiography (MRC) compared with T2-weighted MRC (T2w-MRC) in the detection of biliary leaks.

Methods

Ninety-nine patients with suspected biliary complications underwent routine T2w-MRC and T1w contrast-enhanced (CE) MRC using Gd-EOB-DTPA to identify biliary leaks. Two observers reviewed the image sets separately and together. MRC findings were compared with those of surgery and percutaneous transhepatic cholangiopancreatography. The sensitivity, specificity and accuracy of the techniques in identifying biliary leaks were calculated.

Results

Accuracy of locating biliary leaks was superior with the combination of Gd-EOB-DTPA-enhanced MRC and T2w-MRC (P?<?0.05).The mean sensitivities were 79 % vs 59 %, and the mean accuracy rates were 84 % vs 58 % for combined CE-MRC and T2w-MRC vs sole T2w-MRC. Nineteen out of 21 patients with biliary-cyst communication, 90.4 %, and 12/15 patients with post-traumatic biliary extravasations, 80 %, were detected by the combination of Gd-EOB-DTPA-enhanced MRC and T2w-MRC images, P?<?0.05.

Conclusions

Gd-EOB-DTPA-enhanced MRC yields information that complements T2w-MRC findings and improves the identification and localisation of the bile extravasations (84 % accuracy, 100 % specificity, P?<?0.05). We recommend Gd-EOB-DTPA-enhanced MRC in addition to T2w-MRC to increase the preoperative accuracy of identifying and locating extravasations of bile.

Key Points

? Magnetic resonance cholangiography (MRC) does not always detect bile leakage and cysto-biliary communications. ? Gd-EOB-DTPA-enhanced MRC helps by demonstrating extravasation of contrast material into fluid collections. ? Gd-EOB-DTPA-enhanced MRC also demonstrates the leakage site and bile duct injury type. ? Combined Gd-EOB-DTPA-enhanced and T2w-MRC can provide comprehensive information about biliary system. ? Gd-EOB-DTPA-enhanced MRC is non-invasive and does not use ionising radiation.  相似文献   
74.
BACKGROUND AND PURPOSE: Various sedative and analgesic medication has been used for shockwave lithotripsy (SWL). The aim of this study was to evaluate the efficacy of different anesthesia modalities in these patients. PATIENTS AND METHODS: One hundred patients were randomly divided into four groups. The first (Group F) received fentanyl 1 microg/kg intravenously (IV), the second (Group D) received diclofenac sodium 1 mg/kg intramuscularly (IM), the third (Group T) received tramadol 1.5 mg/kg IM, and the fourth (Group E) was given 15 g of eutectic mixture local anesthetic (EMLA) cream containing lidocaine and prilocaine. After routine preoperative evaluation, all patients received midazolam 2 mg IV 5 minutes before lithotripsy for sedative premedication. In all groups, a supplemental 25-microg bolus of fentanyl was administered IV when patients complained of pain, moved, or grimaced in response to the shockwaves. Pain intensity was evaluated on a 0- to 100-mm visual analog scale (VAS). The level of sedation was determined using the Observer's Assessment of Alertness/Sedation (OAS/S). Side effects such as bradypnea, oxygen desaturation, bradycardia, pruritus, and nausea and vomiting were recorded. RESULTS: There were no statistically significant differences among the four groups with regard to VAS, OAS/S scores, or side effects. In Group F, the mean arterial pressure was decreased significantly at 10 and 20 minutes. The patients in this group also manifested a decrease of oxygen saturation at the first, tenth, and twentieth minutes and the end of SWL. CONCLUSION: Application of EMLA cream was as safe and effective as fentanyl, diclofenac, and tramadol, and reduction of the fentanyl dose during SWL was possible.  相似文献   
75.
We report magnetic resonance (MR), computed tomography (CT) and angiographic imaging of an unusual giant arachnoid granulation in the superior sagittal sinus in a man with headache and vertigo. Intrasinus pressure measurements revealed a significant pressure gradient across the lesion. MR imaging is useful to identify giant arachnoid granulation and dural sinus thrombosis, whereas dural sinus pressure measurement in certain cases of giant arachnoid granulations can be used to evaluate the lesion as the cause of the patient's symptoms.  相似文献   
76.
Wilson's disease is an inherited disorder of copper metabolism characterized by reduced biliary copper excretion, which results in copper accumulation in the tissues with liver injury and failure. Orthotopic liver transplantation (OLT) can be lifesaving for patients with Wilson's disease who present with fulminant liver failure and for patients' unresponsive to medical therapy. The aim of this study was to review our experience with OLT for patients with Wilson's disease. Between September 2001 and April 2007, 25 OLTs were performed in 24 patients (7 females and 17 males) with Wilson's disease of mean age 15.6 +/- 9.9 years (range, 5-51 years). Six patients underwent transplantation owing to coexistent fulminant hepatic failure and 18 with chronic advanced liver disease with (n = 8) or without (n = 10) associated neurologic manifestations. We performed 3 full-size, deceased-donor OLTs and 22 living-related donor OLTs. Eight patients had a family history of Wilson's disease. We detected a Kayser-Fleischer ring in 18 patients. All patients had a low serum ceruloplasmin level (mean, 27.8 mg/dL) and a high urinary copper excretion level (mean, 4119 mug/d) before OLT. Following successful OLT, there was a significant reduction in urinary copper excretion (median, 37.1 mug/d) in all patients. Mean follow-up was 21.7 +/- 19.8 months (range, 2-60 months). Retransplantation was required in 1 patient at 12 days after the first OLT owing to primary graft nonfunction. Five of the 24 patients died within 4 months of the surgery. The remaining 19 survivors (79%) have remained well, with normal liver function and no disease recurrence. In conclusion, OLT was a curative procedure for Wilson's disease among patients presenting with fulminant hepatic failure and others with end-stage hepatic insufficiency. After OLT, the serum ceruloplasmin level increased to the normal range, urinary copper excretion decreased, and neurologic manifestations improved.  相似文献   
77.
Acquired non-traumatic frontal sinus encephaloceles are very rare lesions that are usually caused by a tumour or hydrocephalus. We present a 31-year-old woman with a frontal sinus encephalocele who developed rhinorrhoea after a ventriculo-peritoneal shunt to treat her hydrocephalus and underwent radiotherapy for a tectum tumour.  相似文献   
78.
79.
This study investigated the effect of rifampin on the thickness of capsules around silicone implants by bactericidal activity against Stapylococcus epidermidis. Silicone blocks (1 × 1 cm) were placed into pockets created for each of the 40 rats included in the study. In group 1, the operation was performed under aseptic conditions. In group 2, standard S. epidermidis was inoculated into the pocket, whereas rifampin and S. epidermidis were applied in group 3. In group 4, only rifampin was applied topically on implants. After 12 weeks, the peri-implant capsules were removed and examined under a photomicroscope and a scanning electron microscope. The mean thickness of the capsules was 63.307 μm in group 1, 111.538 μm in group 2, 43.076 μm in group 3, and 30.384 μm in group 4. The differences between groups 2 and 3 and groups 2 and 4 were found to be statistically significant (p < 0.001). Rifampin appears to be an agent for preventing peri-implant capsule formation.  相似文献   
80.
PURPOSE: We previously demonstrated that assessment of the number of positive cores, tumor length in a core, Gleason score and prostate volume significantly enhanced the accuracy of a prediction model for low volume/low grade cancer in men who had undergone extended biopsy. To determine the validity of the model, we applied it to an independent population of men with prostate cancer. MATERIALS AND METHODS: The study group included 170 men who had undergone radical prostatectomy without neoadjuvant therapy. In all cases, prostate cancer was diagnosed on only 1 positive core of a 10-core extended biopsy. We assessed the accuracy of the model, which consists of tumor length less than 2 mm, Gleason score 3+4 or less and prostate gland volume greater than 50 cc in predicting the occurrence of low volume/low grade cancer (defined as tumor volume less than 0.5 cc, no Gleason grade 4 or 5 disease, and organ confined disease). RESULTS: Of the patients 101 (59.4%) had low volume/low grade cancer. Our model using all 3 previously mentioned variables had the highest performance, demonstrating a positive predictive value of 70.4% (88 of 125), a negative predictive value of 71.1% (32 of 45) and a diagnostic accuracy of 70.6% (120 of 170). This model performed better than a model based on tumor length only (positive predictive value, negative predictive value and diagnostic accuracy 68.1%, 57.9% and 64.7%, respectively) or a model based on tumor length and Gleason score (positive predictive value, negative predictive value and diagnostic accuracy 70.0%, 60.0% and 66.5%, respectively). CONCLUSIONS: This study validates that our model with a combination of tumor length, Gleason score and prostate volume is predictive for low volume/low grade cancer in an independent population of men who demonstrated only 1 positive core in an extended biopsy. This model can be used as a tool for selecting men for active surveillance.  相似文献   
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