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101.
102.
The authors developed and evaluated a method to automatically create interactive vascular curved planar reformations with computed tomographic (CT) angiographic data. The method decreased user interaction time by 86%, from 15 to 2 minutes. Expert reviewers were asked to indicate their confidence in differentiating automatically created images from clinical-quality manually produced images. The area under the receiver operating characteristic curve was 0.45 (95% CI: 0.39, 0.51), and a test of equivalency indicated that reviewers could not distinguish between images. They also graded image quality as equivalent to that with manual methods and found fewer artifacts on automatically created images. Automatic methods rapidly produce curved planar reformations of equivalent quality with reduced time and effort. 相似文献
103.
104.
Wong CY Salem R Raman S Gates VL Dworkin HJ 《European journal of nuclear medicine and molecular imaging》2002,29(6):815-820
The purpose of this prospective study was to evaluate yttrium-90 glass microsphere treatment of unresectable liver metastases by fluorine-18 fluorodeoxyglucose positron emission tomography ([18F]FDG PET), and to compare the effectiveness of [18F]FDG PET for this purpose with that of computed tomography (CT) or magnetic resonance imaging (MRI) and determination of the serum carcinoembryonic antigen (CEA) level. Thirteen hepatic lobes from eight consecutive patients with colorectal cancer referred for 90Y-glass microsphere treatment of unresectable liver metastases who underwent both baseline (pretreatment) and 3-month posttreatment PET were studied. All patients also had correlative pre- and posttreatment CT or MRI for evaluation of the anatomic response and serum CEA determination for assessment of the total tumor load, as well as pretreatment hepatic intra-arterial technetium-99m macroaggregated albumin scan for lung shunting evaluation and hepatic arteriography for assessment of vascular anatomy and treatment. 90Y-glass microspheres were infused via an intra-arterial catheter under low pressure. Dedicated whole-body PET scans were analyzed visually and compared by lesion and by lobe with CT or MRI. A metabolic response after 90Y treatment to single or both hepatic lobes, assessed by PET, was present in a significantly higher proportion of the lobes than was an anatomic response, evaluated by CT or MRI (12 vs 2 lobes respectively, P<0.0002). Posttreatment PET showed no, stable, progressive, and new extrahepatic metastases in two, three, one, and two patients respectively. Following treatment, serum CEA decreased significantly, correlating with PET but not with CT or MRI. Thus, the study demonstrated a significant difference between the metabolic and the anatomic response after 90Y-glass microsphere treatment for unresectable liver metastases in colorectal cancer. PET appears to be an accurate indicator of treatment response. 相似文献
105.
106.
Andrew Kaines Garry Davis Dinesh Selva Igal Leibovitch Thomas Dodd Raman Malhotra 《Ophthalmic surgery, lasers & imaging》2005,36(3):249-251
Conjunctival squamous cell carcinoma is generally a low-grade malignancy. A 42-year-old man presented with histologic evidence of extra-tumoral perineural invasion associated with an incompletely excised limbal conjunctival squamous cell carcinoma. Despite further surgery, close observation, plaque radiotherapy, and eyelid-sparing orbital exenteration followed by external beam radiotherapy, the patient developed intracranial perineural invasion with involvement of the trigeminal and facial nerves, ultimately resulting in death. Repeated magnetic resonance imaging with contrast failed to detect perineural invasion until late in the course of disease. Awareness of the possibility of perineural invasion in patients with conjunctival squamous cell carcinoma and of its aggressive nature may be life-saving. Nevertheless, even with initial aggressive tumor control, some patients will show an aggressive tumor growth with recurrences. 相似文献
107.
Effects of central dopaminergic stimulation by apomorphine on speech in Parkinson's disease 总被引:2,自引:0,他引:2
OBJECTIVE: To determine the effect of central dopaminergic stimulation with apomorphine on speech in PD. BACKGROUND: Most patients with PD have a speech disorder. Of those, 89% have involvement of laryngeal function, and 45% have additional articulatory dysfunction. The effect of dopaminergic medications on these two dimensions of speech impairment in PD has not been selectively studied. METHODS: In a randomized, double-blind, placebo-controlled crossover design, patients with PD and speech impairment, Hoehn and Yahr stages 2 to 4 "off," and without severe dyskinesias were given placebo or apomorphine injections 0.05 mg/kg subcutaneously during two consecutive outpatient visits. They were pretreated with domperidone for 48 hours and were tested off their parkinsonian medications for 12 hours. Laryngeal function was assessed by maximum sustained vowel phonations and comfortable vowel phonations. Articulatory function was evaluated by speech intelligibility score, speaking rate, and efficiency ratio. RESULTS: Ten patients, mean age 73.4 years (SD = 6.6), disease duration 8.7 years (SD = 6.3), were tested. The baseline motor score on the Unified Parkinson's Disease Rating Scale (UPDRSm) and all experimental speech variables were equivalent on both placebo and apomorphine days. At a dose of apomorphine that provoked improvement in UPDRSm (p = 0.0078), no index of either laryngeal or articulatory function improved significantly after apomorphine administration. CONCLUSION: Laryngeal and articulatory speech components are not under prominent dopaminergic control in PD. Treatment regimens should focus on nondopaminergic pharmacology and other therapies. 相似文献
108.
Goetz CG Burke PF Leurgans S Berry-Kravis E Blasucci LM Raman R Zhou L 《Archives of neurology》2001,58(2):209-213
BACKGROUND: Visual hallucinations in Parkinson disease (PD) occur in approximately one third of patients treated long-term with dopaminergic medications. In Alzheimer disease, hallucinations and psychosis have been linked to increased representations of B2/B2 homozyogotes for the dopamine receptor gene DRD1 and 1/1 or 2/2 homozygotes for DRD3. In addition, a previous study of PD patients with and without hallucinations did not show differences in D2 and D3 polymorphisms, although careful case-control matching was not performed. Another study linked the apolipoprotein E4 (APOE4) allele to hallucinations in PD. OBJECTIVE: To determine whether the frequency of dopamine receptor genetic variants and APOE alleles in patients with PD with and without chronic visual hallucinations resembles the pattern previously documented in patients with Alzheimer disease. METHODS: We conducted a case-control study of 44 patients with PD and chronic hallucinations and 44 patients with PD who had never hallucinated. Cases and controls were matched for current age and medications. DNA was isolated from blood samples and assayed for DRD1, DRD2, DRD3, DRD4, and APOE polymorphisms. Receptor polymorphisms were genotyped by polymerase chain reaction. Genotypes in hallucinators and nonhallucinators were compared using Mantel-Haenszel tests stratified by pair, and allele frequencies were compared using Wilcoxon signed rank tests within pairs. RESULTS: Neither D1 receptor genotypes (P =.37) nor allele frequencies (P =.38) differed, and there was no predominance of B2/B2 homozygotes in the hallucinators. For D3, there was a higher frequency of allele 2 (P =.047), but there was no significant difference between frequencies of homozygotes vs heterozygotes (P =.39) as reported in Alzheimer disease. D4 receptor distribution of long and short alleles did not differ between the 2 patient groups, and there were too few C alleles (3 of 86) to compare D2 allele genotypes or frequencies. For APOE, 12 cases and 12 controls carried E4 alleles (P>.99). CONCLUSIONS: With careful case-control matching, visual hallucinations in PD are not associated with the pattern seen for patients with Alzheimer disease and visual hallucinations. Furthermore, there was no association between hallucinations and APOE. Similar methods using larger sample sizes might be adapted to test whether specific dopaminergic receptor genetic variants are associated with visual hallucinations in PD. Based on our data, the DRD3 allele 2 may merit further study. 相似文献
109.
Early and intensive continuous hemofiltration for severe renal failure after cardiac surgery 总被引:13,自引:0,他引:13
Bent P Tan HK Bellomo R Buckmaster J Doolan L Hart G Silvester W Gutteridge G Matalanis G Raman J Rosalion A Buxton BF 《The Annals of thoracic surgery》2001,71(3):832-837
BACKGROUND: The aim of this study was to test whether early and intensive use of continuous venovenous hemofiltration (CVVH) achieved a better than predicted outcome in patients with severe acute renal failure undergoing cardiac operations, and whether a simple and yet accurate model could be developed to predict their outcome before starting CVVH. METHODS: Medical record analysis with collection of demographic, clinical, and outcome information was used. RESULTS: Sixty-five consecutive patients were treated with early and intensive CVVH (mean operation to CVVH time, 2.38 days; pump-controlled ultrafiltration rate, 2 L/h) after coronary artery bypass grafting (56.9%), single valve procedure (16.9%), or combined operations (26.2%). In 32.3% of patients, intraaortic balloon counterpulsation was required and 20% of patients were emergencies. Sustained hypotension despite inotropic and vasopressor support occurred in 40% of patients and prolonged mechanical ventilation in 58.5%. Using an outcome prediction score specific for acute renal failure, the predicted risk of death was 66%. Actual mortality was 40% (p = 0.003). Using multivariate logistic regression analysis and neural network analysis, patient outcome could be predicted with good levels of accuracy (receiver operating characteristic 0.89 and 0.9, respectively). CONCLUSIONS: Early and aggressive CVVH is associated with better than predicted survival in severe acute renal failure after cardiac operations. Using readily available clinical data, the outcome of such patients can be predicted before the implementation of CVVH. 相似文献
110.
Raman Kaul Frank Hendrickson Lionel Cohen Ivan Rosenberg Randall Ten Haken Miguel Awschalom Joanne Mansell 《International journal of radiation oncology, biology, physics》1981,7(12):1667-1671
Fast neutrons were used in the management of 30 patients with advanced salivary gland tumors. Twenty-two patients are the subject of this analysis. Neutrons were used as the primary mode of management in only seven patients. The remaining patients either had recurrent disease after surgery and/or radiation, or received post-operative treatment with neutrons. After a minimum follow-up of one year, 66% of the patients are alive with no evidence of disease. Control in the treatment volume is as high as 72%, which suggests a significant improvement in the local control of advanced salivary gland tumors. However, longer periods of observation are necessary for more definitive conclusions. 相似文献