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Leaflet escape in contemporary mechanical valves is an extremely rare and potentially lethal condition. We report the case of a 77-year-old man who presented with embolization of a leaflet from an On-X mitral valve (CryoLife, Kennesaw, GA) with Conform-X Sewing Ring prosthesis (CryoLife) after exercise. The patient recovered completely 6 months after surgery, and he is currently asymptomatic.
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Próteses Valvulares Cardíacas , Valva Mitral/cirurgia , Falha de Prótese , Idoso , Implante de Prótese de Valva Cardíaca , Humanos , Masculino , Desenho de Prótese , Indução de Remissão , RetratamentoRESUMO
OBJECTIVE: To assess the sensitivity and specificity of blue-light cystoscopy (BLC) with hexaminolevulinate as an adjunct to white-light cystoscopy (WLC) vs WLC alone for the detection of non-muscle-invasive bladder cancer (NMIBC), in routine clinical practice in Spain. PATIENTS AND METHOD: An intra-patient comparative, multicentre, prospective, observational study. Adults with suspected or documented primary or recurrent NMIBC at eight Spanish centres were included in the study. All patients were examined with WLC followed by BLC with hexaminolevulinate. We evaluated the detection rate of bladder cancer lesions by WLC and BLC with hexaminolevulinate, overall and by tumour stage and compared with histological examination of the biopsied lesions. Sensitivity and specificity was calculated. RESULTS: In all, 1,569 lesions were identified from 283 patients: 621 were tumour lesions according to histology and 948 were false-positives. Of the 621 tumour lesions, 475 were detected by WLC (sensitivity 76.5%, 95% confidence interval [CI] 73.2-79.8) and 579 were detected by BLC (sensitivity 93.2%, 95% CI 91.0-95.1; P < 0.001). There was a significant improvement in the sensitivity in the detection of all types of NMIBC lesions with BLC compared with WLC. Of 219 patients with tumours, 188 had NMIBC [highest grade: carcinoma in situ (CIS), n = 36; Ta, n = 87; T1, n = 65). CIS lesions were identified more with BLC (n = 27) than with WLC [n = 19; sensitivity: BLC 75.0% (95% CI 57.8-87.9) vs WLC 52.8% (95% CI 35.5-69.6); P = 0.021]. Results varied across centres. CONCLUSIONS: This study shows that improvement in diagnosis of NMIBC, mainly CIS and Ta tumours, obtained with BLC with hexaminolevulinate as an adjunct to WLC vs WLC alone can be shown in routine clinical practice.
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Ácido Aminolevulínico/análogos & derivados , Cistoscopia/métodos , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , EspanhaRESUMO
OBJECTIVES: White light cystoscopy is the current standard for the diagnosis of bladder cancer and monitorization for recurrence. Recent studies suggest that porphyrin based fluorescence cystoscopy may improve endoscopic detection of bladder tumors. We aimed to evaluate the improvement that hexaminolevulinate fluorescence cystoscopy could lead in bladder cancer detection and treatment at one single centre. METHODS: Between September 2006 and September 2007 a total of 39 patients with known or suspected bladder cancer underwent bladder instillation with 50 ml 8 mM hexaminolevulinate (HAL) for 1 hour. The bladder was inspected using white light cystoscopy (WLC), followed by blue light (fluorescence) cystoscopy (BLC). Papillary and suspicious lesions were resected for histological examination. Mean age was 70.1 years (50-86). Thirty patients were male (76.9%) and 9 female (23.1%). The tumor characteristics were: 18% primary tumors, 51% recurrences and 30% control cystoscopies. 24 patients had previously received some treatment (9 MMC and 15 BCG). Only 7 patients had previous positive urine cytology. RESULTS: All papillary lesions visualized with WLC were confirmed by BLC (18 patients). From these, 17 have positive biopsies (6 pTaG1, 9 pT1G1-3, 1 pT2, 1 CIS). In 15 patients (38.4%) we found at least 1 lesion more with BLC. In this group 8 cases (20.5%) had positive histological diagnosis (3 pTaG1, 2 pT1G3, 3 CIS). In five patients (13%) post-TUR therapeutic management has changed by using BLC (BCG vs MMC). All four patients with CIS were diagnosed by BLC. There was no evidence of local or systemic side effects due to HAL in the postoperative time. CONCLUSIONS: Our results suggest there is an improvement in the diagnosis of papillary and flat lesions in bladder cancer by using HAL fluorescence cystoscopy. This has changed the management in the postoperative period (MMC vs BCG) in 13% of the patients. Obviously, we need more patients to assess our data and long-term follow-up to analyze the impact in terms of tumor recurrence and progression.
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Ácido Aminolevulínico/análogos & derivados , Radioisótopos de Carbono , Cistoscopia/métodos , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluorescência , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Guided wave scattering in a plate overlap is investigated by numerical calculations and experimental measurements of transmission and reflection factors from the overlap region. In the numerical study, a hybrid boundary element-finite element method is used to calculate the guided wave scattered field from the overlap region. Transmission and reflection factors are calculated for incident A0 and S0 Lamb and n0 shear horizontal waves, including higher modes generated through mode conversion phenomena. In addition, parametric studies of transmission and reflection factors in this problem are performed numerically over various incident modes, frequencies, and overlap lengths. For verification and comparison with numerical results, experiments were conducted to measure the transmission and reflection factors for incident Lamb and shear horizontal waves in steel plates with two different overlap areas. The experimental results agree well with the numerical calculations. The numerical and experimental results show that it is highly feasible to carry out efficient Lamb wave nondestructive evaluation (NDE) in overlapped plates and in multilayer structures with various lap joints by selecting various modes and tuning frequency.
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Two general and flexible numerical techniques based on the finite-element and boundary element methods developed by the authors in a previous paper are applied to study Lamb wave propagation in multilayered plates and Lamb mode conversion at free edges for frequencies beyond the first cutoff frequency. Both techniques are supported by a meshing criterion which guarantees the accuracy of the results when a condition is fulfilled. A finite-element formulation is directly applicable to study Lamb wave propagation and reflection by simple obstacles such as a flat edge. In order to tackle Lamb wave diffraction problems by defects with more complex geometries, a hybrid boundary element-finite-element formulation is used. This technique provides a major improvement with respect to the only previous boundary element application on Lamb waves: the connecting boundary might be placed as close to the reflector as desired, reducing greatly the requirement on mesh size. Two main application problems on practical metallic plates are studied and compared with reported numerical, theoretical, and experimental results: (1) Lamb wave propagation in degraded titanium diffusion bonds, and (2) Lamb mode conversion at inclined or perpendicular free edges of steel plates for frequencies beyond the first cutoff frequency.
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OBJECTIVES: Prostatic brachytherapy by permanent implant of I125 or Pd103 is a therapeutic option in the treatment of organ confined prostate cancer We analyze preliminary results and complications after five years in the group of patients who received I125 low dose rate brachytherapy as the only intention-to-cure treatment and evaluate the differences with the standard treatment (surgery). METHODS: From a case series of more than 400 patients treated with brachytherapy as radical intention-to-cure monotherapy for organ-confined prostate cancer we excluded patients with less than 12 months of follow-up for statistical analysis; the study group includes 275 patients enrolled between april 1999 and December 2003. Mean follow-up is 31 months (12-68). Biochemical failure was defined in accordance to the ASTRO criteria. Statistical survival analysis was carried out with the SPSS statistical software using the Kaplan Meyer method. Urinary and gastrointestinal complications were evaluated in accordance to the RTOG criteria. RESULTS: Mean age was 68 years (range 49-83 years). 93% of the patients presented a clinical stage < or ='3dT2a and 7% T2b, with 60 8% of the cases having a PSA < or ='3d 10 ng/ml. Gleason score was < or ='3d 6 in 94% of the cases. 9% of the cases had a prostate volume > 50 cc. Overall 5 year survival was 96%, with a 97% disease-free survival and a 99% biochemical failure-free survival. Figure 3 and tables II-VI summarize the complications in various series including this. CONCLUSIONS: Multiple published series seem to show similar results on biochemical control of the disease when comparing surgery and low dose rate brachytherapy in organ-confined disease. In comparison to surgery, brachytherapy has the advantage of having a lower percentage of immediate postoperative complications, lower incontinence rate, and a higher number of patients preserving erectile function.
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Adenocarcinoma/radioterapia , Braquiterapia/métodos , Radioisótopos do Iodo/administração & dosagem , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Fatores de TempoRESUMO
The remote inspection for defects in large metallic elements such as pipes, tubes and plates is a field where guided waves are being applied with success. There are a number of situations where a surface coating is added for corrosion protection or insulation purposes. Since the coating materials are usually viscoelastic, the guided wave inspection range may be severely reduced unless a proper mode and an adequate frequency range is selected. Previous authors found the existence of low-attenuated modes at certain frequency ranges, which were used to detect and locate defects at reasonably large distances. This paper studies the potential of guided waves for not only locating but also sizing defects in plates with viscoelastic coatings. A hybrid finite element-boundary element method which explicitly includes the attenuating characteristics of the coating is used to determine Lamb and SH mode conversion factors at corrosion defects under the coating. Through parametric studies and analysis of the numerical results, some trends and features are highlighted that could be used for sizing purposes.