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1.
Biomedicines ; 11(12)2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38137559

RESUMO

Osteoradionecrosis (ORN) is a serious long-term complication of head and neck radiotherapy (RT), which is often triggered by dental extractions. It results from avascular aseptic necrosis due to irradiated bone damage. ORN is challenging to treat and can lead to severe complications. Furthermore, ORN causes pain and distress, significantly reducing the patient's quality of life. There is currently no established preventive strategy. This narrative review aims to provide an update for the clinicians on the risk of ORN associated with oral surgery in head and neck RT patients, with a focus on the timing suitable for the oral surgery and possible ORN preventive treatments. An electronic search of articles was performed by consulting the PubMed database. Intervention and observational studies were included. A multidisciplinary approach to the patient is highly recommended to mitigate the risk of RT complications. A dental visit before commencing RT is highly advised to minimize the need for future dental extractions after irradiation, and thus the risk of ORN. Post-RT preventive strategies, in case of dento-alveolar surgery, have been proposed and include antibiotics, hyperbaric oxygen (HBO), and the combined use of pentoxifylline and tocopherol ("PENTO protocol"), but currently there is a lack of established standards of care. Some limitations in the use of HBO involve the low availability of HBO facilities, its high costs, and specific clinical contraindications; the PENTO protocol, on the other hand, although promising, lacks clinical trials to support its efficacy. Due to the enduring risk of ORN, removable prostheses are preferable to dental implants in these patients, as there is no consensus on the appropriate timing for their safe placement. Overall, established standards of care and high-quality evidence are lacking concerning both preventive strategies for ORN as well as the timing of the dental surgery. There is an urgent need to improve research for more efficacious clinical decision making.

2.
BMJ Case Rep ; 16(11)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37967933

RESUMO

Proliferative verrucous leukoplakia (PVL) is a distinct progressive and multi-focal form of oral leukoplakia, not associated with the traditional risk factors (ie, tobacco and alcohol consumption). The incidence of oral squamous cell carcinoma in PVL patients is high. Here, we describe the case of a patient affected by PVL, who developed two metachronous oral verrucous carcinomas at different sites of the oral mucosa. Owing to the high risk of multiple oral squamous cell carcinoma, periodical clinical and histopathological follow-up is mandatory and should continue lifelong.


Assuntos
Carcinoma de Células Escamosas , Carcinoma Verrucoso , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/complicações , Transformação Celular Neoplásica/patologia , Leucoplasia Oral/patologia , Neoplasias de Cabeça e Pescoço/complicações , Carcinoma Verrucoso/cirurgia
3.
Aging Clin Exp Res ; 35(4): 763-773, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36752950

RESUMO

BACKGROUND: Accurate estimation of the imminent fragility fracture risk currently represents a challenging task. The novel Fragility Score (FS) parameter, obtained during a Radiofrequency Echographic Multi Spectrometry (REMS) scan of lumbar or femoral regions, has been developed for the non-ionizing estimation of skeletal fragility. AIMS: The aim of this study was to assess the performance of FS in the early identification of patients at risk for incident fragility fractures with respect to bone mineral density (BMD) measurements. METHODS: Data from 1989 Caucasians of both genders were analysed and the incidence of fractures was assessed during a follow-up period up to 5 years. The diagnostic performance of FS to discriminate between patients with and without incident fragility fracture in comparison to that of the BMD T-scores measured by both Dual X-ray Absorptiometry (DXA) and REMS was assessed through ROC analysis. RESULTS: Concerning the prediction of generic osteoporotic fractures, FS provided AUC = 0.811 for women and AUC = 0.780 for men, which resulted in AUC = 0.715 and AUC = 0.758, respectively, when adjusted for age and body mass index (BMI). For the prediction of hip fractures, the corresponding values were AUC = 0.780 for women and AUC = 0.809 for men, which became AUC = 0.735 and AUC = 0.758, respectively, after age- and BMI-adjustment. Overall, FS showed the highest prediction ability for any considered fracture type in both genders, resulting always being significantly higher than either T-scores, whose AUC values were in the range 0.472-0.709. CONCLUSION: FS displayed a superior performance in fracture prediction, representing a valuable diagnostic tool to accurately detect a short-term fracture risk.


Assuntos
Fraturas do Quadril , Fraturas por Osteoporose , Feminino , Humanos , Masculino , Densidade Óssea , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/epidemiologia , Absorciometria de Fóton/métodos , Fraturas do Quadril/epidemiologia , Análise Espectral
5.
Respir Med ; 189: 106644, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34653873

RESUMO

OBJECTIVE: To assess the effectiveness of 3 novel lung ultrasound (LUS)-based parameters: Pneumonia Score and Lung Staging for pneumonia staging and COVID Index, indicating the probability of SARS-CoV-2 infection. METHODS: Adult patients admitted to the emergency department with symptoms potentially related to pneumonia, healthy volunteers and clinical cases from online accessible databases were evaluated. The patients underwent a clinical-epidemiological questionnaire and a LUS acquisition, following a 14-zone protocol. For each zone, a Pneumonia score from 0 to 4 was assigned by the algorithm and by an expert operator (kept blind with respect to the algorithm results) on the basis of the identified imaging signs and the patient Lung Staging was derived as the highest observed score. The output of the operator was considered as the ground truth. The algorithm calculated also the COVID Index by combining the automatically identified LUS markers with the questionnaire answers and compared with the nasopharyngeal swab results. RESULTS: Overall, 556 patients were analysed. A high agreement between the algorithm assignments and the expert operator evaluations was observed, both for Pneumonia Score and Lung Staging, with the latter having sensitivity and specificity over 92% both in the discrimination between healthy/sick patients and between sick patients with mild/severe pneumonia. Regarding the COVID Index, an area under the curve of 0.826 was observed for the classification of patients with/without SARS-CoV-2. CONCLUSION: The proposed methodology allowed the identification and staging of patients suffering from pneumonia with high accuracy. Moreover, it provided the probability of being infected by SARS-CoV-2.


Assuntos
COVID-19/diagnóstico por imagem , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Projetos de Pesquisa/normas , Ultrassonografia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/complicações , Bases de Dados Factuais , Feminino , Humanos , Doenças Pulmonares Intersticiais/classificação , Doenças Pulmonares Intersticiais/complicações , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Inquéritos e Questionários , Adulto Jovem
7.
Antibiotics (Basel) ; 9(3)2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32187989

RESUMO

Background: Actinomycosis of the tongue is an uncommon, suppurative infection of lingual mucosa, caused by actinomyces. The clinical diagnosis may present serious difficulties because of its ability to mimic other lesions, including both benign and malignant neoplasms. Methods: Here, we describe the case of a 52-years-old patient affected by an asymptomatic, tumor-like tongue swelling, then diagnosed as actinomycosis. A review of tongue localization of actinomycosis is also reported, with emphasis on clinical findings and therapy. Results and Conclusion: Early diagnosis and treatment, with pus drainage and systemic antibiotic therapy, are pivotal to avoid severe and life-threatening complications.

10.
J Exp Clin Cancer Res ; 35(1): 193, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-27931238

RESUMO

BACKGROUND: Tumor-positive sentinel lymph node (SLN) biopsy results in a risk of non sentinel node metastases in micro- and macro-metastases ranging from 20 to 50%, respectively. Therefore, most patients underwent unnecessary axillary lymph node dissections. We have previously developed a mathematical model for predicting patient-specific risk of non sentinel node (NSN) metastases based on 2460 patients. The study reports the results of the validation phase where a total of 1945 patients were enrolled, aimed at identifying a tool that gives the possibility to the surgeon to choose intraoperatively whether to perform or not axillary lymph node dissection (ALND). METHODS: The following parameters were recorded: Clinical: hospital, age, medical record number; Bio pathological: Tumor (T) size stratified in quartiles, grading (G), histologic type, lymphatic/vascular invasion (LVI), ER-PR status, Ki 67, molecular classification (Luminal A, Luminal B, HER-2 Like, Triple negative); Sentinel and non-sentinel node related: Number of NSNs removed, number of positive NSNs, cytokeratin 19 (CK19) mRNA copy number of positive sentinel nodes stratified in quartiles. A total of 1945 patients were included in the database. All patient data were provided by the authors of this paper. RESULTS: The discrimination of the model quantified with the area under the receiver operating characteristics (ROC) curve (AUC), was 0.65 and 0.71 in the validation and retrospective phase, respectively. The calibration determines the distance between predicted outcome and actual outcome. The mean difference between predicted/observed was 2.3 and 6.3% in the retrospective and in the validation phase, respectively. The two values are quite similar and as a result we can conclude that the nomogram effectiveness was validated. Moreover, the ROC curve identified in the risk category of 31% of positive NSNs, the best compromise between false negative and positive rates i.e. when ALND is unnecessary (<31%) or recommended (>31%). CONCLUSIONS: The results of the study confirm that OSNA nomogram may help surgeons make an intraoperative decision on whether to perform ALND or not in case of positive sentinel nodes, and the patient to accept this decision based on a reliable estimation on the true percentage of NSN involvement. The use of this nomogram achieves two main gools: 1) the choice of the right treatment during the operation, 2) to avoid for the patient a second surgery procedure.


Assuntos
Neoplasias da Mama/cirurgia , Queratina-19/genética , Excisão de Linfonodo/métodos , Nomogramas , Técnicas de Amplificação de Ácido Nucleico/métodos , Neoplasias da Mama/genética , Feminino , Dosagem de Genes , Humanos , Período Intraoperatório , Metástase Linfática , Modelos Teóricos , Gradação de Tumores , Micrometástase de Neoplasia , Curva ROC , Estudos Retrospectivos
11.
Cochrane Database Syst Rev ; 7: CD001829, 2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27471845

RESUMO

BACKGROUND: Oral leukoplakia is a relatively common oral lesion that, in a small proportion of people, precedes the development of oral cancer. Most leukoplakias are asymptomatic; therefore, the primary objective of treatment should be to prevent onset of cancer. This review updates our previous review, published in 2006. OBJECTIVES: To assess the effectiveness, safety and acceptability of treatments for leukoplakia in preventing oral cancer. SEARCH METHODS: We searched the following electronic databases: Cochrane Oral Health's Trials Register (to 16 May 2016), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2016, Issue 4), MEDLINE Ovid (1946 to 16 May 2016), Embase Ovid (1980 to 16 May 2016) and CancerLit via PubMed (1950 to 16 May 2016). We searched the metaRegister of Controlled Trials (to 10 February 2015), ClinicalTrials.gov (to 16 May 2016) and the World Health Organization (WHO) International Clinical Trials Registry Platform for ongoing trials (to 16 May 2016). We placed no restrictions on the language or date of publication when searching electronic databases. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that enrolled people with a diagnosis of oral leukoplakia and compared any treatment versus placebo or no treatment. DATA COLLECTION AND ANALYSIS: We collected data using a data extraction form. Oral cancer development, demonstrated by histopathological examination, was our primary outcome. Secondary outcomes were clinical resolution of the lesion, improvement of histological features and adverse events. We contacted trial authors for further details when information was unclear. When valid and relevant data were available, we conducted a meta-analysis of the data using a fixed-effect model when we identified fewer than four studies with no heterogeneity. For dichotomous outcomes, we calculated risk ratios (RRs) and 95% confidence intervals (CIs). We assessed risk of bias in studies by using the Cochrane tool. We assessed the overall quality of the evidence by using standardised criteria (Grades of Recommendation, Assessment, Development and Evaluation Working Group (GRADE)). MAIN RESULTS: We included 14 studies (909 participants) in this review. Surgical interventions, including laser therapy and cryotherapy, have never been studied by means of an RCT that included a no treatment or placebo arm. The included trials tested a range of medical and complementary treatments, in particular, vitamin A and retinoids (four studies); beta carotene or carotenoids (three studies); non-steroidal anti-inflammatory drugs (NSAIDs), specifically ketorolac and celecoxib (two studies); herbal extracts (four studies), including tea components, a Chinese herbal mixture and freeze-dried black raspberry gel; bleomycin (one study); and Bowman-Birk inhibitor (one study).We judged one study to be at low risk of bias, seven at unclear risk and six at high risk. In general, we judged the overall quality of the evidence to be low or very low, so findings are uncertain and further research is needed.Five studies recorded cancer incidence, only three of which provided useable data. None of the studies provided evidence that active treatment reduced the risk of oral cancer more than placebo: systemic vitamin A (RR 0.11, 95% CI 0.01 to 2.05; 85 participants, one study); systemic beta carotene (RR 0.71, 95% CI 0.24 to 2.09; 132 participants, two studies); and topical bleomycin (RR 3.00, 95% CI 0.32 to 27.83; 20 participants, one study). Follow-up ranged between two and seven years.Some individual studies suggested effectiveness of some proposed treatments, namely, systemic vitamin A, beta carotene and lycopene, for achieving clinical resolution of lesions more often than placebo. Similarly, single studies found that systemic retinoic acid and lycopene may provide some benefit in terms of improvement in histological features. Some studies also reported a high rate of relapse.Side effects of varying severity were often described; however, it seems likely that interventions were well accepted by participants because drop-out rates were similar between treatment and control groups. AUTHORS' CONCLUSIONS: Surgical treatment for oral leukoplakia has not been assessed in an RCT that included a no treatment or placebo comparison. Nor has cessation of risk factors such as smoking been assessed. The available evidence on medical and complementary interventions for treating people with leukoplakia is very limited. We do not currently have evidence of a treatment that is effective for preventing the development of oral cancer. Treatments such as vitamin A and beta carotene may be effective in healing oral lesions, but relapses and adverse effects are common. Larger trials of longer duration are required to properly evaluate the effects of leukoplakia treatments on the risk of developing oral cancer. High-quality research is particularly needed to assess surgical treatment and to assess the effects of risk factor cessation in people with leukoplakia.


Assuntos
Leucoplasia Oral/terapia , Neoplasias Bucais/prevenção & controle , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Ultrasound Med Biol ; 42(6): 1337-56, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27033331

RESUMO

The aim of this paper was to investigate the clinical feasibility and the accuracy in femoral neck densitometry of the Osteoporosis Score (O.S.), an ultrasound (US) parameter for osteoporosis diagnosis that has been recently introduced for lumbar spine applications. A total of 377 female patients (aged 61-70 y) underwent both a femoral dual X-ray absorptiometry (DXA) and an echographic scan of the proximal femur. Recruited patients were sub-divided into a reference database used for ultrasound spectral model construction and a study population for repeatability assessments and accuracy evaluations. Echographic images and radiofrequency signals were analyzed through a fully automatic algorithm that performed a series of combined spectral and statistical analyses, providing as a final output the O.S. value of the femoral neck. Assuming DXA as a gold standard reference, the accuracy of O.S.-based diagnoses resulted 94.7%, with k = 0.898 (p < 0.0001). Significant correlations were also found between O.S.-estimated bone mineral density and corresponding DXA values, with r(2) up to 0.79 and root mean square error = 5.9-7.4%. The reported accuracy levels, combined with the proven ease of use and very good measurement repeatability, provide the adopted method with a potential for clinical routine application in osteoporosis diagnosis.


Assuntos
Colo do Fêmur/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Ultrassonografia/métodos , Absorciometria de Fóton/métodos , Idoso , Densidade Óssea , Densitometria/métodos , Estudos de Avaliação como Assunto , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
13.
Breast J ; 22(3): 339-341, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26923527

RESUMO

Basal cell carcinoma (BCC) is a common skin cancer worldwide. However, BCC of the nipple and areola complex is rare. Men are more affected than women. Most of the cases were treated with simple excision. We report a case of BCC of the right nipple-areola complex in a 75-year-old man, treated with Mohs surgery and simple mastectomy.

14.
Nanomaterials (Basel) ; 6(4)2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28335194

RESUMO

Aim of this work was to investigate the automatic echographic detection of an experimental drug delivery agent, halloysite clay nanotubes (HNTs), by employing an innovative method based on advanced spectral analysis of the corresponding "raw" radiofrequency backscatter signals. Different HNT concentrations in a low range (5.5-66 × 1010 part/mL, equivalent to 0.25-3.00 mg/mL) were dispersed in custom-designed tissue-mimicking phantoms and imaged through a clinically-available echographic device at a conventional ultrasound diagnostic frequency (10 MHz). The most effective response (sensitivity = 60%, specificity = 95%), was found at a concentration of 33 × 1010 part/mL (1.5 mg/mL), representing a kind of best compromise between the need of enough particles to introduce detectable spectral modifications in the backscattered signal and the necessity to avoid the losses of spectral peculiarity associated to higher HNT concentrations. Based on theoretical considerations and quantitative comparisons with literature-available results, this concentration could also represent an optimal concentration level for the automatic echographic detection of different solid nanoparticles when employing a similar ultrasound frequency. Future dedicated studies will assess the actual clinical usefulness of the proposed approach and the potential of HNTs for effective theranostic applications.

16.
Ultrasound Med Biol ; 41(1): 281-300, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25438845

RESUMO

We investigated the possible clinical feasibility and accuracy of an innovative ultrasound (US) method for diagnosis of osteoporosis of the spine. A total of 342 female patients (aged 51-60 y) underwent spinal dual X-ray absorptiometry and abdominal echographic scanning of the lumbar spine. Recruited patients were subdivided into a reference database used for US spectral model construction and a study population for repeatability and accuracy evaluation. US images and radiofrequency signals were analyzed via a new fully automatic algorithm that performed a series of spectral and statistical analyses, providing a novel diagnostic parameter called the osteoporosis score (O.S.). If dual X-ray absorptiometry is assumed to be the gold standard reference, the accuracy of O.S.-based diagnoses was 91.1%, with k = 0.859 (p < 0.0001). Significant correlations were also found between O.S.-estimated bone mineral densities and corresponding dual X-ray absorptiometry values, with r(2) values up to 0.73 and a root mean square error of 6.3%-9.3%. The results obtained suggest that the proposed method has the potential for future routine application in US-based diagnosis of osteoporosis.


Assuntos
Densidade Óssea , Densitometria/métodos , Osteoporose/diagnóstico por imagem , Osteoporose/fisiopatologia , Doenças da Coluna Vertebral/diagnóstico por imagem , Doenças da Coluna Vertebral/fisiopatologia , Ultrassonografia/métodos , Estudos de Viabilidade , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
J Clin Pathol ; 67(8): 702-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24906358

RESUMO

AIMS: Cytokeratin 19 (CK19) mRNA copy number predicts the probability of tumour load in axillary lymph nodes (ALN) and can help in decision-making regarding the axillary dissection. The purpose of this study was to define a new cut-off of CK19 mRNA copy number using the one-step nucleic acid amplification (OSNA) assay on metastatic sentinel lymph nodes (SLN) in order to identify cases at risk of having one or more positive ALN. METHODS: 1296 SLN from 1080 patients were analysed with the OSNA assay. 194 patients with positive SLN underwent ALN dissection and the mean value of CK19 copy number (320 000) of their SLN was set as initial cut-off. Receiver operative characteristics curve identify a best cut-off of 7700 (sensitivity 78%, specificity 57%). A comparison between our and the traditional cut-off (5000) was performed. RESULTS: The cut-off of 7700 successfully identifies patients with positive ALN (p=0.001, false- negative cases: 17%). In the range between 5000 and 7700, one patient with positive ALN would not undergo axillary dissection, whereas eight patients with negative ALN would be correctly identified. CONCLUSIONS: We suggest that the level of CK19 mRNA copy number could be the only parameter to consider in the intraoperative management of the axilla.


Assuntos
Neoplasias da Mama/genética , Queratina-19/genética , Linfonodos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Excisão de Linfonodo , Pessoa de Meia-Idade , RNA Mensageiro , Estudos Retrospectivos , Sensibilidade e Especificidade , Biópsia de Linfonodo Sentinela
18.
Pain Pract ; 13(8): 627-32, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23336607

RESUMO

Burning mouth syndrome (BMS) is a chronic condition most common in middle-aged and elderly women, with prevalence rates in the general population ranging from 0.5% to 5%. Defined by the International Headache Society as "an intraoral burning sensation for which no medical or dental cause can be found," BMS is considered a form of neuropathic pain. The management of BMS remains unsatisfactory. In this pilot study, we investigated the use of acupuncture in a small group of BMS patients. The study group, after 4 refusals, was composed of 10 BMS patients (9 females and 1 male; mean age, 65.2 years; range, from 48 to 80 years; mean duration of BMS, 2.6 years; SD ± 0.8 years). Oral pain/burning sensation (primary outcome) was measured using a visual analogue scale (VAS). Health-related quality of life (secondary outcome) was measured using the 36-item Short-Form Health Survey (SF-36). Acupuncture treatment lasted 8 weeks and consisted of 20 sessions. Patients reported a mean reduction in pain of 0.99 points on the VAS (max 2.1-min 0.1), which, although slight, was statistically significant (Wilcoxon test P < 0.009). No significant improvement in the overall score for quality of life was observed, although subjects receiving acupuncture treatment seemed better able cope with their oral symptoms.


Assuntos
Terapia por Acupuntura , Síndrome da Ardência Bucal/terapia , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Projetos Piloto
19.
Artigo em Inglês | MEDLINE | ID: mdl-23221218

RESUMO

Prototypal software algorithms for advanced spectral analysis of echographic images were developed to perform automatic detection of simulated tumor masses at two different pathological stages. Previously published works documented the possibility of characterizing macroscopic variation of mechanical properties of tissues through elastographic techniques, using different imaging modalities, including ultrasound (US); however, the accuracy of US-based elastography remains affected by the variable manual modality of the applied compression and several attempts are under investigation to overcome this limitation. Quantitative US (QUS), such as Fourier- and wavelet-based analyses of the RF signal associated with the US images, has been developed to perform a microscopic-scale tissue-type imaging offering new solutions for operator-independent examinations. Because materials able to reproduce the harmonic behavior of human liver can be realized, in this study, tissue-mimicking structures were US imaged and the related RF signals were analyzed using wavelet transform through an in-house-developed algorithm for tissue characterization. The classification performance and reliability of the procedure were evaluated on two different tumor stiffnesses (40 and 130 kPa) and with two different applied compression levels (0 and 3.5 N). Our results demonstrated that spectral components associated with different levels of tissue stiffness within the medium exist and can be mapped onto the original US images independently of the applied compressive forces. This wavelet-based analysis was able to identify different tissue stiffness with satisfactory average sensitivity and specificity: respectively, 72.01% ± 1.70% and 81.28% ± 2.02%.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Neoplasias/diagnóstico por imagem , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Algoritmos , Humanos , Hidrogéis , Modelos Biológicos , Imagens de Fantasmas , Álcool de Polivinil , Sensibilidade e Especificidade , Software
20.
Artigo em Inglês | MEDLINE | ID: mdl-21989874

RESUMO

Current imaging methods for catheter position monitoring during minimally invasive surgery do not provide an effective support to surgeons, often resulting in the choice of more invasive procedures. This study was conducted to demonstrate the feasibility of non-ionizing monitoring of endovascular devices through embedded quantitative ultrasound (QUS) methods, providing catheter self-localization with respect to selected anatomical structures. QUS-based algorithms for real-time automatic tracking of device position were developed and validated on in vitro and ex vivo phantoms. A trans-esophageal ultrasound probe was adapted to simulate an endovascular device equipped with an intravascular ultrasound probe. B-mode images were acquired and processed in real time by means of a new algorithm for accurate measurement of device position. After off-line verification, automatic position calculation was found to be correct in 96% and 94% of computed frames in the in vitro and ex vivo phantoms, respectively. The average errors of distance measurements (bias ± 2SD) in a 41-step 10-cm-long parabolic pathway were 0.76 ± 3.75 mm or 0.52 ± 3.20 mm, depending on algorithm implementations. Our results showed the effectiveness of QUS-based tracking algorithms for real-time automatic calculation and display of endovascular system position. The method, validated for the case of an endoclamp balloon catheter, can be easily extended to most endovascular surgical systems.


Assuntos
Cateterismo/métodos , Processamento de Imagem Assistida por Computador/métodos , Cirurgia Assistida por Computador/métodos , Ultrassonografia de Intervenção/métodos , Algoritmos , Animais , Aorta Torácica/diagnóstico por imagem , Cateterismo/instrumentação , Bovinos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Cirurgia Assistida por Computador/instrumentação , Ultrassonografia de Intervenção/instrumentação
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