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101.
Objective To describe the different imaging modalities used for the diagnosis and classification of hydrocephalus, their role in defining
the optimal treatment of hydrocephalus and to define the optimal preoperative diagnostics for endoscopic third ventriculocisternostomy
(ETV).
Methods An overview on available imaging modalities for hydrocephalus will be given and their pros and cons discussed. In addition,
different aspects of the treatment of hydrocephalus by shunts and by ETV will be highlighted.
Discussion The role of the technical aspects of performing an ETV, the role of the surgeon’s philosophy, the role of the urgency of the
procedure, and the role of informed consent on the requirements for the imaging of the hydrocephalus will be discussed.
Conclusion The authors conclude that MRI is a conditio sine qua non for ETV in elective surgical cases. 相似文献
102.
Jorge Polónia Nuno Carvalho Loide Barbosa José A Silva 《Revista portuguesa de cardiologia》2006,25(7-8):693-704
INTRODUCTION: It is still controversial whether subjects with white-coat hypertension (WCHT) exhibit higher cardiovascular risk compared to normotensive subjects (NT). In subjects with WCHT it is not known whether the abnormal blood pressure (BP) reaction in the office also occurs at other times of day, particularly on arising and immediately after waking, i.e. the times at which the majority of cardiovascular events are reported to occur. OBJECTIVE AND METHODS: To evaluate with 24h ambulatory BP measurement the values of morning BP surge, BP on arising and BP variability in subjects with WCHT in comparison with age-, gender- and weight-matched normotensives (BP) and untreated sustained hypertensives (BP). RESULTS: Groups of BP, WCHT and BP were matched for age, gender and body weight: BP: n=69, age 49 +/- 7 years, 54 % female, BMI 26 +/- 1, casual BP 126/79 +/- 5/4 mmHg, daytime BP 124/80 +/- 6/6 mmHg; WCHT: n=74, age 52 +/- 8 years, 57% female, BMI 26 +/- 2, casual BP 152/95 +/- 7/7 mmHg, daytime BP 126/80 +/- 5/6 mmHg; HT: n=79, age 53 +/- 7 years, 56% female, BMI 27 +/- 2, casual BP 154/97 +/- 9/8 mmHg, daytime BP 143/89 +/- 12/10 mmHg. Of the three groups, subjects with WCHT exhibited BP on arising (121/81 +/- 13/8 mmHg) similar to that of NTs (120/80 +/- 13/9 mmHg, NS), both significantly lower than that of HTs (137/92 +/- 17/10 mmHg, p < 0.01), suggesting the absence of an alerting BP reaction in WCHT at that time. By contrast, subjects with WCHT showed higher values of systolic morning BP surge vs. NTs (25 +/- 10 vs. 22 +/- 11 mmHg, p < 0.05), both lower than that observed in hypertensives (33 +/- 11 mmHg, p < 0.01 vs. NT and WCHT) and greater daytime variability (systolic BP standard variation), i.e. 12 2 vs. 10 +/- 2 mmHg, p < 0.05, both lower than that observed in hypertensives (14 +/- 3 mmHg, p < 0.01 vs. NT and WCHT). CONCLUSIONS: Although subjects with WCHT did not show any alerting blood pressure reaction on arising, morning BP surge and BP variability were greater in these subjects than in control normotensives, although lower than sustained hypertensives. Although this is still speculative, we cannot exclude the possibility that even a slight increase in morning BP surge might in the long term constitute an additional load on the circulation that could increase cardiovascular risk in subjects with WCHT compared to matched normotensives. 相似文献
103.
Sandrine Cappellesso Jean-Fran?ois Valentin Bruno Giraudeau Marie-Denise Boulanger Azmi Al-Najjar Mathias Büchler Jean-Michel Halimi Hubert Nivet Pierre Bardos Yvon Lebranchu Hervé Watier 《Nephrology, dialysis, transplantation》2004,19(2):439-443
BACKGROUND: Genetic factors other than HLA have been reported to be associated with the outcome of organ transplantations. Because binding of FasL to its receptor Fas could play an important role in tubulitis and in the death of graft tubular epithelial cells during kidney allograft rejection, a gene polymorphism recently identified in position -671 in the promoter of the TNFRSF6 gene coding for Fas was investigated in donors. METHODS: A case-control study was performed within a cohort of non-hyperimmunized adult patients who had received cadaveric kidney transplants based on the occurrence or absence of acute cellular rejection in the first 6 months after renal transplantation. Each recipient from the acute rejection group (n = 35) was matched for age (+/- 5 years) and number of HLA-DR mismatches with two recipients within the non-acute rejection group (n = 70). RESULTS: The TNFRSF6-GG genotype was more frequent in donors in the group without rejection episodes. In contrast, patients who received a kidney from a TNFRSF6-A carrier were more likely to experience acute rejection episodes (relative risk nearly 2.1). CONCLUSION: This study suggests that donor TNFRSF6 polymorphism directly or indirectly influences acute kidney rejection episodes. 相似文献
104.
Use of stereotactic PET images in dosimetry planning of radiosurgery for brain tumors: clinical experience and proposed classification. 总被引:13,自引:0,他引:13
Marc Levivier Nicolas Massager David Wikler José Lorenzoni Salvador Ruiz Daniel Devriendt Philippe David Fran?oise Desmedt Stéphane Simon Paul Van Houtte Jacques Brotchi Serge Goldman 《Journal of nuclear medicine》2004,45(7):1146-1154
We developed a technique that allows the routine integration of PET in stereotactic neurosurgery, including radiosurgery. We report our clinical experience with the combined use of metabolic (i.e., PET) and anatomic (i.e., MRI and CT) images for the radiosurgical treatment of brain tumors. We propose a classification describing the relative role of the information provided by PET in this multimodality image-guided approach. METHODS: Between December 1999 and March 2003, 57 patients had stereotactic PET as part of their image acquisition for the planning of gamma knife radiosurgery. Together with stereotactic MRI and CT, stereotactic PET images were acquired on the same day using either (18)F-FDG or (11)C-methionine. PET images were imported in the planning software for the radiosurgery dosimetry, and the target volume was defined using the combined information of PET and MRI or CT. To analyze the specific contribution of the PET findings, we propose a classification that reflects the strategy used to define the target volume. RESULTS: The patients were offered radiosurgery with PET guidance when their tumor was ill-defined and we anticipated some limitation of target definition on MRI alone. This represents 10% of the radiosurgery procedures performed in our center during the same period of time. There were 40 primary brain lesions, 7 metastases, and 10 pituitary adenomas. Abnormal PET uptake was found in 62 of 72 targets (86%), and this information altered significantly the MRI-defined tumor in 43 targets (69%). CONCLUSION: The integration of PET in radiosurgery provides additional information that opens new perspectives for the optimization of the treatment of brain tumors. 相似文献
105.
Guilherme Santoro-Lopes Erika Ferraz de Gouvêa Rodrigo Carreira M Monteiro Rodrigo Castelo Branco José Rodolfo Rocco Márcia Halpern Adriana Lúcia Pires Ferreira Elaine Gama Pessoa de Araújo Samanta T Basto Vinicius Gomes Silveira Joaquim Ribeiro-Filho 《Liver transplantation》2005,11(2):203-209
Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of infection after orthotopic liver transplantation (OLT). Colonization with MRSA is associated with a higher risk of infection. Previous studies have shown a high prevalence of MRSA colonization among OLT candidates. However, the risk of colonization with MRSA after OLT is still unclear. The objective of this study was to estimate the incidence and the factors associated with colonization with MRSA after OLT. This was a prospective cohort study including patients submitted to OLT between the years 2000 and 2002. Surveillance cultures of nasal swab specimens were performed within the 1st 72 hours of hospital admission and, subsequently, on weeks 2, 6, 13, and 26. Patients whose baseline cultures revealed nasal carriage of MRSA were excluded. A total of 60 patients were included in the study. The median follow-up was 72 days. A total of 9 patients (15%) became colonized. In multiple logistic regression analyses, the use of a urinary catheter for > or =5 days (P = .006), postoperative bleeding at the surgical site (P = .009), and preoperative use of fluoroquinolones (P = .08) were associated with a higher risk of colonization. Patients without any of these risk factors did not become colonized. In conclusion, nasal carriage of MRSA is frequently acquired after OLT. Periodic postoperative screening for MRSA carriage should be an integral component in programs designed to reduce nosocomial MRSA transmission in these patients. Further studies are needed to set up and validate a predictive model that could allow targeting postoperative screening to high-risk OLT recipients. 相似文献
106.
José A Pe?agarícano Nikos Papanikolaou Yulong Yan Emad Youssef Vaneerat Ratanatharathorn 《Radiotherapy and oncology》2005,76(1):72-78
BACKGROUND AND PURPOSE: Helical tomotherapy can eliminate the need for junction lines. The goal of this study is to evaluate tomotherapy in the delivery of CSA radiation and measurement of plan quality using physical parameters in comparing conventional (CSA-RT) and helical tomotherapy (CSA-TOMO) plans. PATIENTS AND METHODS: CSA-TOMO and CSA-RT plans were created for dosimetric comparison. Integral dose values were calculated. The ratios D50% (dose received by 50% of the organ at risk's volume) and D10% (dose received by 10% of the organ at risk's volume) were calculated representing large volumes and small volumes of organs at risk receiving significant dose. RESULTS: When considering D50% and D10%, CSA-TOMO has a dosimetric advantage over CSA-RT for most organs at risk. The body integral dose was higher for the CSA-TOMO plan by approximately 6.5%. CONCLUSIONS: Tomotherapy is a feasible alternative for treatment of CSA. Analysis shows that tomotherapy improves dose ratios over conventional radiation for most organs at risk. The impact of a small increase in whole body integral dose is unknown. Long-term follow-up will be needed to answer this question as others have argued of the possibility of increased risk of secondary malignancies due to delivery of radiotherapy with IMRT. 相似文献
107.
Guilherme Janson Karina Santana Cruz Donald G Woodside Angelos Metaxas Marcos Roberto de Freitas José Fernando Castanha Henriques 《American journal of orthodontics and dentofacial orthopedics》2004,126(4):451-463
The objective of this study was to evaluate the dentoskeletal changes consequent to orthodontic treatment in subjects with Class II subdivision malocclusions, treated with asymmetric extractions, compared with a normal-occlusion control group. The sample consisted of 3 groups, with 30 subjects in each: normal-occlusion subjects (group 1), untreated Class II subdivision subjects (group 2), and Class II subdivision patients treated with asymmetric extractions (group 3). All subjects had a full complement of permanent teeth at the beginning of treatment. The average ages of the subjects were 22.42, 15.76, and 18.57 years, respectively, in groups 1, 2, and 3. Measurements of relative differences in the spatial position of dental and skeletal bilateral landmarks were obtained from the submentovertex and posteroanterior cephalometric (PA) radiographs. The t test for independent samples was used to compare group 1 with groups 2 and 3 at different times. Results from the submentovertex radiograph showed that asymmetric extractions in Class II subdivision malocclusions will maintain the differences in the anteroposterior positions of right and left, maxillary and mandibular first molars, as would be expected with the treatment protocols used. There were no significant skeletal changes that could be attributed to the treatment approaches investigated or transverse collateral effects with the asymmetric mechanics used. It was also demonstrated that treatment of Class II subdivision malocclusions with asymmetric extractions produced corrections of maxillary and mandibular dental midline deviations with the midsagittal plane, without canting the occlusal plane or any other investigated horizontal plane, as seen in the PA radiograph. Treatment of Class II subdivision malocclusions with asymmetric extractions constitutes a beneficial approach to this problem. 相似文献
108.
Serge Evrard Yves Bécouarn René Brunet Marianne Fonck Caroline Larrue Simone Mathoulin-Pélissier 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(1):41-44
BACKGROUND AND AIMS: The aim of this work was to test the feasibility of using a bipolar low thermal acting system inducing collagenic sealing but not protein coagulation to secure hepatic parenchyma cutting. MATERIALS AND METHODS: Thirty consecutive hepatectomies were carried out using kellyclasy plus ligatures and clips (controls), while the following 50 hepatectomies used kellyclasy plus bipolar vessels sealer (BVS). Blood loss, duration of hepatic pedicle clamping, length of hospital stay, and complications were recorded. RESULTS: There was no statistically significant difference in blood loss and duration of clamping between controls and BVS. Specific complications (9/21 in the control group vs 1/49 for the BVS group, p<0.00045) and length of hospital stay (14 days in the control group vs 11 days in the BVS group, p<0.014) were statistically lower in BVS group than in the controls, mainly due to prevention of bile duct leakages. CONCLUSIONS: Our data suggest that BVS may be particularly efficient to achieve bilistasis leading to the highest level of safety in performing hepatectomies. Further studies are now needed to confirm its superiority on the classical biliary ducts occlusion techniques. 相似文献
109.
Catarina Eira Jordi Miquel José Vingada Jordi Torres 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(2):119-122
Gongylonema neoplasticum was identified in the oesophagus of 14 wild rabbits (Oryctolagus cuniculus) from Portugal. This is the first record of Gongylonema neoplasticum in a naturally infected lagomorph species in Europe. This paper presents the most relevant measurements of adult worms and
some of their surface features seen by scanning electron microscopy. Epidemiological aspects of G. neoplasticum such as geographical distribution, host spectrum and biological features are discussed. 相似文献
110.
Alfredo Avellaneda Fernández álvaro Pérez Martín Maravillas Izquierdo Martínez Mar Arruti Bustillo Francisco Javier Barbado Hernández Javier de la Cruz Labrado Rafael Díaz-Delgado Pe?as Eduardo Gutiérrez Rivas Cecilia Palacín Delgado José Ramón Ramón Giménez Javier Rivera Redondo 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2009,41(10):e1-e5