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1.
Acta Paediatr ; 108(6): 1049-1054, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30461053

RESUMO

AIM: We evaluated the weight, insulin-like growth factor-1, neonatal, retinopathy of prematurity (WINROP) algorithm for very premature infants. METHOD: Infants born before 32 weeks who had undergone fundus examinations in the neonatal intensive care unit at the University Hospital of Nancy were included in this French retrospective cohort study from July 2012 to July 2016. We evaluated how well the WINROP software predicted threshold retinopathy of prematurity (ROP). RESULTS: We studied 570 infants with a mean gestational age of 28.7 ± 1.8 weeks and a mean birth weight of 1110 ± 297 g: 28.1% had ROP and 1.2% had threshold ROP. The overall WINROP sensitivity was 57.1%, specificity was 46.0%, predictive positive value was 1.3% and predictive negative value was 98.9%. At more than 30 weeks of gestation or 1250 g, these figures rose to a respective specificity of 100% and 95.7% and respective predictive negative value of 100% and 100%. There were independent associations between the severity of ROP and the Apgar score at five minutes, the duration of oxygen therapy and non-invasive ventilation. CONCLUSION: WINROP worked better on preterm infants born from 31 weeks onwards or weighing over 1250 g. Fundus examinations remain necessary for infants born earlier or lighter.


Assuntos
Algoritmos , Fundo de Olho , Exame Físico , Retinopatia da Prematuridade/diagnóstico , Peso ao Nascer , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Fator de Crescimento Insulin-Like I/análise , Masculino , Valor Preditivo dos Testes , Retinopatia da Prematuridade/sangue , Estudos Retrospectivos
2.
Nanotechnology ; 25(12): 125702, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24572071

RESUMO

Exploiting the intrinsic photosensitivity of TiO2 nanoparticles, we demonstrated how ultraviolet (UV) pulsed laser irradiation of acrylate polymer nanocomposite solutions can separate the initial clusters of these colloidal semiconductor nanorods into clearly distinct units. From the irradiated solutions, optically clear nanocomposite films are obtained which exhibit enhanced optical properties with respect to the nanocomposites obtained without previous UV treatment.

3.
J Fr Ophtalmol ; 47(6): 104188, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636198

RESUMO

INTRODUCTION: Open globe injuries are a major cause of visual impairment in children, related to the severity of the trauma or secondary to induced amblyopia. Intraocular foreign bodies (IOFB) have been reported in approximately one third of cases of open globe injuries. As clinical presentation and management may differ between adults and children, data is lacking about IOFBs in children under 18years of age. The purpose of this study was to assess the clinical characteristics and visual prognosis of ocular trauma associated with intraocular foreign bodies in children. MATERIALS AND METHODS: This single-center retrospective study included patients under 18years of age treated for ocular trauma with IOFB. Demographic characteristics, complete initial and final ophthalmological examination, imaging data and details of medical and surgical management were collected. RESULTS: Fourteen patients were included (78.6% boys), with a mean age of 10.3years (min 7months-max 17years). In 92.9% of cases, patients were found to have a single IOFB, mostly metallic (71.4%). Posterior segment IOFBs were found in 50% of cases, anterior segment IOFBs in 28.6% and orbital IOFBs in 21.4%. The clinical examination permitted detection of the IOFBs in 50% of cases, while they were visible on CT scan in all cases. The mean initial visual acuity was 20/320, and the mean final visual acuity was 20/125. Endophthalmitis occurred in 2 cases (14%). DISCUSSION: Open globe injuries associated with IOFB are severe and sight-threatening. Localization of the IOFB in the posterior segment has a worse prognosis. CT scan is mandatory, especially in children, as the trauma history is often missing. Retinal detachment and endophthalmitis appear to be the main prognostic factors requiring urgent specialized pediatric ophthalmology management.


Assuntos
Corpos Estranhos no Olho , Ferimentos Oculares Penetrantes , Humanos , Corpos Estranhos no Olho/diagnóstico , Corpos Estranhos no Olho/epidemiologia , Corpos Estranhos no Olho/complicações , Corpos Estranhos no Olho/cirurgia , Estudos Retrospectivos , Masculino , Criança , Feminino , Pré-Escolar , Lactente , Adolescente , Ferimentos Oculares Penetrantes/diagnóstico , Ferimentos Oculares Penetrantes/epidemiologia , Ferimentos Oculares Penetrantes/complicações , Ferimentos Oculares Penetrantes/cirurgia , Acuidade Visual , Prognóstico
4.
Updates Surg ; 75(3): 735-741, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36877431

RESUMO

COVID-19 pandemic had an impact on surgical activities. The aim of this multi-centric, retrospective study was to evaluate the impact of the COVID-19 pandemic on breast surgery. The patients who operated during the pre-pandemic year 2019 were compared to those operated in 2020. Fourteen Breast Care Units provided data on breast surgical procedures performed in 2020 and 2019: total number of breast-conserving surgery (BCS), number of 1st level oncoplastic breast surgery (OBS), number of 2nd level OBS; total number of mastectomies, mastectomies without reconstruction, mastectomies with a tissue expander, mastectomies with direct to implant (DTI) reconstruction, mastectomies with immediate flap reconstruction; total number of delayed reconstructions, number of expanders to implant reconstructions, number of delayed flap reconstructions. Overall 20.684 patients were included: 10.850 (52.5%) operated during 2019, and 9.834 (47.5%) during 2020. The overall number of breast oncologic surgical procedures in all centers in 2020 was 8.509, compared to 9.383 in 2019 (- 9%). BCS decreased by 744 cases (- 13%), the overall number of mastectomies decreased by 130 cases (- 3.5%); mastectomy-BCS ratio was 39-61% in 2019, and 42-58% in 2020. Regarding immediate reconstructive procedures mastectomies with DTI reconstruction increased by 166 cases (+ 15%) and mastectomies with immediate expander reconstruction decreased by 297 cases (- 20%). Breast-delayed reconstructive procedures in all centers in 2020 were 142 less than in 2019 (- 10%). The outburst of the COVID-19 pandemic in 2020 determined an implemented number of mastectomies compared to BCS, an implemented number of immediate breast reconstructions, mainly DTI, and a reduction of expander reconstruction.


Assuntos
Neoplasias da Mama , COVID-19 , Mamoplastia , Humanos , Feminino , Mastectomia , Estudos Retrospectivos , Pandemias , Neoplasias da Mama/cirurgia , Mamoplastia/métodos
5.
J Fr Ophtalmol ; 45(8): 883-893, 2022 Oct.
Artigo em Francês | MEDLINE | ID: mdl-35843764

RESUMO

OBJECTIVE: This study aims to evaluate surgical training in ophthalmology through feedback from residents. MATERIALS AND METHODS: An anonymous questionnaire was created, including 20 items which assessed the number of complete or partial surgical procedures performed during a semester, self-assessment of surgical skills, use of surgical simulators, an overall rating of the surgical training received and some suggestions to improve surgical training. It was sent by email to all residents in training in Île-de-France (DES Île-de-France and Inter-CHU), France. RESULTS: From October 23 to November 7, 2021, 89/137 residents responded to the questionnaire (65%). Since the beginning of their residency, ninety percent of the residents received training using simulators. Over 90% performed all of the technical steps of a "standard" cataract surgery at least once during the semester, and 60% 10 times or more. The least performed technical steps or procedures also received the lowest self-assessment: management of expulsive hemorrhage, open-globe or lacrimal laceration wound suturing, capsular tension ring injection, and intraocular lens explantation. Residents gave an overall average rating of 6.6/10 to their training and suggested some feedback on videos of resident surgeries (67%) and theoretical courses dealing with surgical techniques (61%). DISCUSSION: The increasing use of simulators should improve surgical training. Residents express the need for training regarding surgical complications and emergencies as well as improvement of their technical skills via improved feedback. CONCLUSION: Surgical teaching appears suitable for learning cataract surgery but seems less effective for the management of emergencies and intraoperative complications.


Assuntos
Catarata , Internato e Residência , Oftalmologia , Competência Clínica , Emergências , Humanos , Oftalmologia/educação , Inquéritos e Questionários
6.
J Fr Ophtalmol ; 45(8): 937-945, 2022 Oct.
Artigo em Francês | MEDLINE | ID: mdl-36028452

RESUMO

INTRODUCTION AND OBJECTIVE: Botulinum toxin (BT) is used in a variety of therapeutic applications, including the treatment of strabismus. Two injection techniques coexist - transconjunctival injection and open sky injection. The goal of this study was to evaluate the results of BT injections in esotropia in children under 10 years of age and to compare the two techniques. PATIENTS AND METHOD: This is a retrospective, monocentric study, including children who received BT injections to treat their strabismus by the aforementioned techniques between 2014 and 2017. The results of these injections were recorded, and subgroup analyses (injection technique, age, degree of deviation, type of strabismus) were performed. The primary endpoint was the optimal success rate defined as residual strabismus less than or equal to 10 Δ. RESULTS: The study included 68 children with a mean age of 28.9 months and a mean deviation angle of 34.7 Δ. Patients received 1.2 BT injections. The success rate was 38% at 6 months, 35% at 12 months, and 35% at 24 months. There was 33% transient ptosis and 5% consecutive exotropia. There was no evidence of significant difference in success rate between the transconjunctival and open sky injection methods, baseline angles, age of injection, or type of strabismus. CONCLUSION: BT injection is effective and safe in pediatric esotropia, regardless of the injection method.


Assuntos
Toxinas Botulínicas Tipo A , Esotropia , Fármacos Neuromusculares , Estrabismo , Criança , Pré-Escolar , Esotropia/tratamento farmacológico , Humanos , Músculos Oculomotores , Estudos Retrospectivos , Resultado do Tratamento
7.
Eur Rev Med Pharmacol Sci ; 25(9): 3483-3488, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34002822

RESUMO

OBJECTIVE: Breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL) is a rare form of non-Hodgkin's T-cell lymphoma that develops around breast implants. CASE PRESENTATION: This report illustrates the case of a patient affected by a locally advanced BIA-ALCL which infiltrated the thoracic wall (stage T4N0M0) following implant-based reconstruction after left mastectomy. Given the initial inoperability due to the patient's poor general condition, the treatment plan provided for a primary cycle of systemic neoadjuvant immunotherapy/chemotherapy, surgical removal of the mass, and subsequent systemic chemotherapy/immunotherapy. This resulted in complete remission - the patient remained disease-free even over a year later - without the need for adjuvant radiotherapy. CONCLUSIONS: Our real-life case shows how the existing guidelines can be successfully adapted as part of an individualized approach to advanced and/or difficult cases.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/terapia , Brentuximab Vedotin/uso terapêutico , Imunoterapia , Linfoma Anaplásico de Células Grandes/terapia , Mastectomia , Vincristina/uso terapêutico , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Linfoma Anaplásico de Células Grandes/diagnóstico por imagem , Terapia Neoadjuvante , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada
8.
Ann Oncol ; 21(4): 781-786, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19713248

RESUMO

BACKGROUND: To determine the efficacy and tolerability of capecitabine combined with oxaliplatin (CAPOX) or irinotecan (CAPIRI) as first-line treatment in patients with advanced/metastatic colorectal cancer aged > or =70 years. PATIENTS AND METHODS: Patients aged > or =70 years were randomly assigned to receive CAPOX [oxaliplatin 65 mg/m(2) intravenously (i.v.) days 1 and 8 and capecitabine 1000 mg/m(2) orally b.i.d. days 1-14; q21d] or CAPIRI (irinotecan 80 mg/m(2) i.v. days 1 and 8 and capecitabine 1000 mg/m(2) orally b.i.d. days 1-14; q21d). The primary study end point was overall response rate (ORR). RESULTS: Ninety-four patients were enrolled. In an intent-to-treat analysis, 2 complete responses (CRs) and 16 partial responses (PRs) were reported with CAPOX (ORR 38%), and 2 CRs and 15 PRs with CAPIRI (ORR 36%; P = 0.831). Median time to progression was 8 months for CAPOX and 7 months for CAPIRI (P = 0.195), with median survival times of 19.3 months and 14.0 months (P = 0.165), respectively. Global health status was improved in 45% and in 21% of patients in the CAPOX and CAPIRI arms, respectively. The most common treatment-related grade 3-4 adverse events in CAPIRI versus CAPOX patients were diarrhea (32% versus 15%; P = 0.052) and neutropenia (23% versus 6%; P = 0.021). CONCLUSION: CAPOX and CAPIRI had similar efficacy in elderly patients, although CAPOX seemed to be better tolerated.


Assuntos
Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Carcinoma/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Compostos Organoplatínicos/administração & dosagem , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Capecitabina , Carcinoma/mortalidade , Carcinoma/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Progressão da Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Irinotecano , Masculino , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Qualidade de Vida , Análise de Sobrevida , Resultado do Tratamento
9.
Nanotechnology ; 20(15): 155302, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19420544

RESUMO

A method of in situ formation of patterns of size controlled CdS nanocrystals in a polymer matrix by pulsed UV irradiation is presented. The films consist of Cd thiolate precursors with different carbon chain lengths embedded in TOPAS polymer matrices. Under UV irradiation the precursors are photolyzed, driving to the formation of CdS nanocrystals in the quantum size regime, with size and concentration defined by the number of incident UV pulses, while the host polymer remains macroscopically/microscopically unaffected. The emission of the formed nanocomposite materials strongly depends on the dimensions of the CdS nanocrystals, thus, their growth at the different phases of the irradiation is monitored using spatially resolved photoluminescence by means of a confocal microscope. X-ray diffraction measurements verified the existence of the CdS nanocrystals, and defined their crystal structure for all the studied cases. The results are reinforced by transmission electron microscopy. It is proved that the selection of the precursor determines the efficiency of the procedure, and the quality of the formed nanocrystals. Moreover it is demonstrated that there is the possibility of laser induced formation of well-defined patterns of CdS nanocrystals, opening up new perspectives in the development of nanodevices.

11.
Eur Rev Med Pharmacol Sci ; 23(10): 4448-4457, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31173322

RESUMO

OBJECTIVE: Despite the improvements reached by microsurgeons in the last 30 years, postoperative complications still occur and most of them are the result of venous thrombosis at the pedicle anastomosis. Primary prevention of thrombosis is mandatory and anticoagulant therapy in the preoperative and postoperative period is widely used. Still, there is a lack of consensus in the literature about the best postoperative protocol for microsurgical reconstruction. The authors aimed to review the postoperative antithrombotic regimens described in literature focusing on their effects and risks, and moreover, share their experience. MATERIALS AND METHODS: The authors performed a literature review of postsurgical antithrombotic protocols applied in reconstructive microsurgery. Research on PubMed server was performed typing the terms "antithrombotic", "postoperative", "microsurgery", "free flap pedicle", "anticlotting", "anticoagulant". RESULTS: The authors described the postoperative standardized pro-weight pharmacological protocol applied in their unit: a combination of dextran and heparin. They inhibit more than one pattern of coagulation in order to stop platelet aggregation and thrombin action and, in the meantime, contending fluid loss with plasma expansion. CONCLUSIONS: Nowadays, a non-standardized practice, based on experience, is applied by microsurgeons in postsurgical care; the authors performed a review of the combined antithrombotic therapies described in the literature. A standardized pro-weight pharmacological protocol is proposed; it allows to increase blood flow by volume expander action (Dextran) and thrombin inhibition (Heparin). Still, coagulation cascade and platelet function have a wide variability among humans, as well as the effect of drugs. Achieving an optimal antithrombotic effect and minimizing adverse reactions meantime remains a challenge.


Assuntos
Fibrinolíticos/uso terapêutico , Microcirurgia/métodos , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/tratamento farmacológico , Fibrinolíticos/efeitos adversos , Humanos , Complicações Pós-Operatórias/prevenção & controle
12.
Nanoscale ; 10(5): 2568-2576, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29350231

RESUMO

Lanthanide-activated SrF2 nanoparticles with a multishell architecture were investigated as optical thermometers in the biological windows. A ratiometric approach based on the relative changes in the intensities of different lanthanide (Nd3+ and Yb3+) NIR emissions was applied to investigate the thermometric properties of the nanoparticles. It was found that an appropriate doping with Er3+ ions can increase the thermometric properties of the Nd3+-Yb3+ coupled systems. In addition, a core containing Yb3+ and Tm3+ can generate light in the visible and UV regions upon near-infrared (NIR) laser excitation at 980 nm. The multishell structure combined with the rational choice of dopants proves to be particularly important to control and enhance the performance of nanoparticles as NIR nanothermometers.

13.
J Chemother ; 19(5): 570-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18073157

RESUMO

To investigate the therapeutic value and safety of the biweekly regimen of 5-fluorouracil (5-FU) and leucovorin (LV) plus irinotecan (CPT-11) in patients with previously untreated advanced gastric cancer (AGC). A total of 50 patients (M/F 35/15; median age = 65) with AGC, none of whom had received chemotherapy for advanced disease, were accrued in this trial. Fifteen patients (30%) were 70 years old or older. At the time of their accrual, cytotoxic chemotherapy, consisting of LV 100 mg/m(2) (2-hour i.v. infusion) followed by 5-FU 400 mg/m(2) (bolus) and 5-FU 600 mg/m(2) (22-hour continuous infusion) on therapeutic days 1 and 2 plus CPT-11 180 mg/m(2) (1-hour infusion) on day 1, was initiated. Treatment courses were repeated every 2 weeks until evidence of progressive disease, unacceptable toxicity or withdrawal of consent. All patients were assessable for toxicity and 48 of 50 for response evaluation, having completed at least four courses of chemotherapy. Complete response was achieved in 2 patients (4%, intent to treat) and partial response in 16 (32%) (overall response rate, 36%; 95% confidence interval [CI]: 22%-50%). Twenty-four patients (48%) had stable disease and 6 patients (16%) progressed. The median time to progression was 8 months (95% CI: 6-10 months) and median overall survival 14 months (95% CI: 6-22 months). Between the subgroups of patients <70 years old and 70 or older, there were no significant differences in efficacy. One toxic death occurred. Treatment tolerance was generally mild to moderate and easy to treat. The main grade 3/4 toxicities were neutropenia (32%), diarrhea (16%), and anemia (8%). Grade 3-4 neutropenia was the only treatment-related serious adverse event significantly more common in patients older than those aged <70 (53.3% vs 22.8%, respectively; P = 0.03). Our data suggest that the biweekly regimen of LV and 5-FU plus CPT-11 in untreated patients with AGC is active and has an acceptable safety profile. Further evaluation of this regimen seems to be warranted in a phase III trial.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Irinotecano , Estimativa de Kaplan-Meier , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/mortalidade , Resultado do Tratamento
15.
Burns ; 32(8): 1000-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16949210

RESUMO

An eight years experience in the management of deep hand burns is presented. We reviewed 116 cases of patients surgically treated with escarectomy and skin autograft. Seventy eight of them underwent early surgery within the first 4-6 days from injury, while 38 were conservatively treated in the fist stage and only lately surgery was performed (usually after the 14th day). In all patients, we applied the same post operative topic treatment and rehabilitation protocol. Several months after first admission, only 6(7.7%) of early treated patients needed secondary correction for unaesthetic and functionally debilitating scars versus 14(36.8%) of the late treated group. Our review confirm the importance of performing early surgery of deep burns of the hands, whenever possible, in order to achieve best results and shows it's utility in reducing re-admissions for secondary revisions.


Assuntos
Queimaduras/cirurgia , Traumatismos da Mão/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Cicatriz/cirurgia , Feminino , Deformidades Adquiridas da Mão/etiologia , Deformidades Adquiridas da Mão/cirurgia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prognóstico , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Transplante de Pele/métodos , Fatores de Tempo
16.
Minerva Stomatol ; 55(11-12): 599-609, 2006.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-17211365

RESUMO

AIM: Our research aimed to evaluate the risk of haemorrhage following oral surgical operations, in patients who were undergoing an anticoagulant therapy, and to test the usefulness of the autologous platelet gel in order to control haemostasis. METHODS: A total of 208 patients (84 males/124 females) undergoing an anticoagulant therapy and submitted to oral surgery, were divided at random into 4 groups (A, B, C, D) consisting of 52 patients each, using as criterion of differentiation the kind of treatment we adopted in order to get haemostasis. The patients belonging to the first 3 groups (A, B, C), underwent a surgical operation without discontinuing the dicumarol therapy. In order to get haemostasis, we used: platelet-rich plasma (PRP) and suture, in group A; PRP, haemostatic sponges and suture, in group B; haemostatic sponges, suture and compression by means of gauzes soaked in tranexamic acid in group C. Group D, instead, consisted of patients who underwent a surgical operation, before which the dicumarol therapy had been suspended and replaced by heparincalcium. RESULTS: Patients belonging to the groups A and B showed a very good haemostasis like the patients of group D (control group). As the coumarin therapy didn't need to be discontinued some days before the surgical operation, so the days of hospital stay were reduced and there wasn't the risk of thromboembolism. As to group C (19 males), 6 patients (i.e. 11.5%) showed a good haemostasis, both at once and in the long term, so that they could be discharged on day 2 after surgery. CONCLUSIONS: The results obtained during our research, highly encourage using PRP regularly when carrying out surgical treatments on patients who are undergoing a coumarin therapy.


Assuntos
Técnicas Hemostáticas , Plasma Rico em Plaquetas , Hemorragia Pós-Operatória/terapia , Idoso , Anticoagulantes/efeitos adversos , Dicumarol/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Bucais/efeitos adversos , Hemorragia Pós-Operatória/induzido quimicamente , Fatores de Risco
18.
J Am Coll Cardiol ; 18(1): 120-6, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2050914

RESUMO

Numerous studies have established abnormalities in systolic and diastolic function of the left ventricle in hypertrophic cardiomyopathy. A consistent feature of this disease is reduced diastolic function of the left ventricle, but little information is available regarding right ventricular function in this disease. Cine nuclear magnetic resonance (NMR) imaging has been found to be effective for measuring right ventricular volumes and therefore was used to assess early diastolic filling of the right ventricle in patients with hypertrophic cardiomyopathy. Right ventricular time-volume curves were obtained from cine NMR images in 10 patients with hypertrophic cardiomyopathy and 8 normal subjects. Right ventricular volume was calculated with use of Simpson's algorithm at approximately 18 phases of the cardiac cycle and, from the curve, peak filling rate and filling fraction during the first third of diastole were determined. In patients with hypertrophic cardiomyopathy, peak filling rate tended to be less (176 +/- 46 vs. 305 +/- 50 ml/s, p less than 0.01) and filling fraction decreased (39.5 +/- 13.8 vs. 74.5 +/- 13.3%, p less than 0.01) in comparison with values in normal subjects. Thus, analysis of right ventricular time-volume curves obtained by using cine NMR imaging demonstrated diastolic dysfunction of the right ventricle in hypertrophic cardiomyopathy.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico , Imageamento por Ressonância Magnética/métodos , Função Ventricular Direita/fisiologia , Adulto , Cardiomiopatia Hipertrófica/fisiopatologia , Diástole/fisiologia , Ventrículos do Coração/patologia , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador
19.
J Am Coll Cardiol ; 10(1): 170-7, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3597985

RESUMO

Nuclear magnetic resonance (NMR) imaging is a new, noninvasive approach for imaging the cardiovascular system. Being a three-dimensional technique, NMR imaging has the capability of measuring volumes without the need for assumptions regarding ventricular geometry. In this study, the technique was validated in 19 excised dog hearts, filled with silicone-rubber, imaged using a multislice spin-echo sequence. The volume of the cavity in each slice was calculated from the number of pixels outlined for each slice multiplied by the pixel volume. Ventricular volumes measured by NMR imaging were highly correlated with cast volumes measured by water displacement: right ventricle (RV):RVNMR = 1.05 RVcast - 1.62; r = 0.99, SEE = 0.96 ml; left ventricle (LV):LVNMR = 0.98 LVcast + 0.35, r = 0.98, SEE = 1.48 ml. After validation in casts, NMR imaging volumes were measured in eight living dogs using a multiphasic gated technique to obtain images at 5, 105, 205, 305 and 405 ms after the QRS complex. Cardiac output (CO) and stroke volume (SV) measured by NMR imaging were significantly correlated with thermodilution (TD) measurements (CONMR = 0.63 COTD + 0.51 liters/min; r = 0.78, SEE = 0.57 liters/min; SVNMR = 0.67 SVTD + 1.95 ml; SEE = 5.58 ml). Right and left stroke volumes were closely related (LVSVNMR = 0.9 RVSVNMR + 1.75; r = 0.94, SEE = 4.32 ml), with the slope and intercept of the regression line showing no difference from 1 and 0, respectively. However, volumes determined by NMR imaging underestimated the thermodilution measurements, presumably reflecting the inability to obtain a true systolic image with the present sampling rate.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Volume Sanguíneo , Circulação Coronária , Espectroscopia de Ressonância Magnética , Animais , Cães , Ventrículos do Coração , Modelos Anatômicos , Termodiluição/métodos
20.
J Am Coll Cardiol ; 23(4): 951-8, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8106701

RESUMO

OBJECTIVES: The feasibility of velocity-encoded cine nuclear magnetic resonance (NMR) imaging to measure regurgitant volume and regurgitant fraction in patients with mitral regurgitation was evaluated. BACKGROUND: Velocity-encoded cine NMR imaging has been reported to provide accurate measurement of the volume of blood flow in the ascending aorta and through the mitral annulus. Therefore, we hypothesized that the difference between mitral inflow and aortic systolic flow provides the regurgitant volume in the setting of mitral regurgitation. METHODS: Using velocity-encoded cine NMR imaging at a magnet field strength of 1.5 T and color Doppler echocardiography, 19 patients with isolated mitral regurgitation and 10 normal subjects were studied. Velocity-encoded cine NMR images were acquired in the short-axis plane of the ascending aorta and from the short-axis plane of the left ventricle at the level of the mitral annulus. Two independent observers measured the ascending aortic flow volume and left ventricular inflow volume to calculate the regurgitant volume as the difference between left ventricular inflow volume and aortic flow volume, and the regurgitant fraction was calculated. Using accepted criteria of color flow Doppler imaging and spectral analysis, the severity of mitral regurgitation was qualitatively graded as mild, moderate or severe and compared with regurgitant volume and regurgitant fraction, as determined by velocity-encoded cine NMR imaging. RESULTS: In normal subjects the regurgitant volume was -6 +/- 345 ml/min (mean +/- SD). In patients with mild, moderate and severe mitral regurgitation, the regurgitant volume was 156 +/- 203, 1,384 +/- 437 and 4,763 +/- 2,449 ml/min, respectively. In normal subjects the regurgitant fraction was 0.7 +/- 6.1%. In patients with mild, moderate and severe mitral regurgitation, the regurgitant fraction was 3.1 +/- 3.4%, 24.5 +/- 8.9% and 48.6 +/- 7.6%, respectively. The regurgitant fraction correlated well with the echocardiographic severity of mitral regurgitation (r = 0.87). Interobserver reproducibilities for regurgitant volume and regurgitant fraction were excellent (r = 0.99, SEE = 238 ml; r = 0.98, SEE = 4.1%, respectively). CONCLUSIONS: These findings suggest that velocity-encoded NMR imaging can be used to estimate regurgitant volume and regurgitant fraction in patients with mitral regurgitation and can discriminate patients with moderate or severe mitral regurgitation from normal subjects and patients with mild regurgitation. It may be useful for monitoring the effect of therapy intended to reduce the severity of mitral regurgitation.


Assuntos
Imageamento por Ressonância Magnética/métodos , Insuficiência da Valva Mitral/diagnóstico , Adulto , Velocidade do Fluxo Sanguíneo , Volume Sanguíneo , Débito Cardíaco , Estudos de Casos e Controles , Feminino , Coração/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/anatomia & histologia , Valva Mitral/patologia , Insuficiência da Valva Mitral/fisiopatologia , Filmes Cinematográficos , Reprodutibilidade dos Testes
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