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1.
Radiol Med ; 125(1): 24-30, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31531810

RESUMO

PURPOSE: The increasing number of computed tomography (CT) performed allows the more frequent identification of small, solid pulmonary nodules or ground-glass opacities. Video-assisted thoracic surgery (VATS) represents the standard in most lung resections. However, since VATS limit is the digital palpation of the lung parenchyma, many techniques of nodule localization were developed. The aim of this study was to determine the feasibility and safety of CT-guided microcoil insertion followed by uniportal VATS wedge resection (WR). MATERIALS AND METHODS: Retrospective study in a single institution, including patients undergone CT-guided microcoil insertion prior to uniportal VATS resection between May 2015 and December 2018. The lesion was identified using fluoroscopy. RESULTS: Forty-six consecutive patients were enrolled (22 male and 24 female). On CT: 5 cases of GGO, 2 cases of semisolid nodules, 39 cases of solid nodules. The median pathologic tumor size was 1.21 cm. Neither conversion to thoracotomy nor microcoil dislodgement was recorded. All patients underwent uniportal VATS WR (9/46 underwent completion lobectomy after frozen section). WR median time was 105 min (range 50-150 min). No patients required intraoperative re-resection for positive margins. After radiological procedure, 1 case of hematoma and 2 cases of pneumothorax were recorded. Four complications occurred in the postoperative period. The mean duration of chest drain and length of stay were 2.9 and 4.6 days, respectively. CONCLUSIONS: CT-guided microcoil insertion followed by uniportal VATS resection was a safe and feasible procedure having a minimal associated complications rate and offering surgeons the ease of localization of small intrapulmonary nodules.


Assuntos
Marcadores Fiduciais , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/cirurgia , Radiografia Intervencionista/métodos , Cirurgia Torácica Vídeoassistida , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Hematoma/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/patologia , Duração da Cirurgia , Pneumotórax/etiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida/efeitos adversos , Adulto Jovem
2.
Int J Radiat Oncol Biol Phys ; 106(1): 116-123, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604131

RESUMO

PURPOSE: The aim of this analysis was to assess the 5-year tolerance and survival in patients undergoing hypofractionated stereotactic boost after external beam radiation therapy (EBRT) for intermediate-risk prostate cancer. METHODS AND MATERIALS: Between August 2010 and April 2013, 76 patients with intermediate-risk prostate carcinoma were included in the study. A first course delivered 46 Gy using conventional fractionation. The second course delivered a boost of 18 Gy (3 × 6 Gy) within 10 days using stereotactic body radiation therapy (SBRT). Gastrointestinal and genitourinary toxicities were assessed according to the National Cancer Institute's Common Terminology Criteria for Adverse Events v4.0. Secondary outcome measures were overall, biochemical relapse-free, and relapse-free survival; prostate-specific antigen kinetics; and patient functional status (urinary and sexual) according to the International Index of Erectile Function and International Prostate Symptom Score questionnaires. RESULTS: Sixty patients (79%) were treated by CyberKnife and 16 (21%) by linear accelerator. Median follow-up was 62 months (range, 29-69). The cumulative incidence of genitourinary and gastrointestinal grade ≥2 toxicities at month 60 after the end of radiation therapy was 1.4% (95% confidence interval [CI], 0.1%-6.6%) and 9.3% (95% CI, 4.1%-17.1%), respectively. Biochemical relapse-free and relapse-free survival rates at 5 years were 87.4% (95% CI, 77.1%-93.2%) and 86.2% (95% CI, 75.8-92.3), respectively. The mean (standard deviation) prostate-specific antigen variation within 3 months and 5 years post-radiation therapy was -1.20 ng/mL/mo (0.79) and -1.30 ng/mL/y (1.05), respectively. There was no significant difference between the International Prostate Symptom quality of life score between inclusion and month 60. For the International Index of Erectile Function, there was a significant difference between inclusion and month 60 (P = .005), with a higher proportion of severe/noninterpretable disorders at 60 months. CONCLUSIONS: The results of the trial demonstrate that the EBRT and SBRT combination is well tolerated and yields good efficacy results. These data provide a good basis for comparing EBRT and brachytherapy boost to EBRT and SBRT boost in future prospective studies.


Assuntos
Neoplasias da Próstata/radioterapia , Radiocirurgia/métodos , Reirradiação/métodos , Idoso , Idoso de 80 Anos ou mais , Disfunção Erétil/epidemiologia , Marcadores Fiduciais , Humanos , Masculino , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Prevalência , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade , Hipofracionamento da Dose de Radiação , Radiocirurgia/efeitos adversos , Radiocirurgia/instrumentação , Radiocirurgia/mortalidade , Reirradiação/efeitos adversos , Reto/efeitos da radiação , Fatores de Tempo , Resultado do Tratamento , Bexiga Urinária/efeitos da radiação , Transtornos Urinários/epidemiologia
3.
Presse Med ; 48(10): 1169-1174, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31669007

RESUMO

A wide diversity of diagnostic or therapeutic percutaneous biopsies exists under sonography, under mammography, under MRI or under CT. This review will detail the different techniques for helping diagnosis or therapeutic management.


Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Biópsia Guiada por Imagem/métodos , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Feminino , Marcadores Fiduciais , Humanos , Imagem por Ressonância Magnética Intervencionista/métodos , Mamografia/métodos , Cuidados Pré-Operatórios , Radiologia Intervencionista/métodos , Ultrassonografia de Intervenção
4.
Cancer Radiother ; 23(8): 891-895, 2019 Dec.
Artigo em Francês | MEDLINE | ID: mdl-31615729

RESUMO

Due to high dose gradients, stereotactic body radiation therapy requires high precision in the location of the tumour. Uncertainties in the positioning can introduce serious damage on organs at risk and consequently can reduce tumour local control. A better tumour location can be achieved by controlling its position with an efficient inter and intrafraction imaging procedure. The various imaging techniques available on treatment systems are presented and performances are discussed. Finally, propositions are given in terms of imaging system according to the location treated by stereotactic body radiation therapy.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Radiocirurgia/métodos , Radioterapia Guiada por Imagem/métodos , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/radioterapia , Fracionamento da Dose de Radiação , Marcadores Fiduciais , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/radioterapia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Imagem por Ressonância Magnética , Masculino , Neoplasias Otorrinolaringológicas/diagnóstico por imagem , Neoplasias Otorrinolaringológicas/radioterapia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/radioterapia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Erros de Configuração em Radioterapia
5.
J Vet Sci ; 20(5): e51, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31565894

RESUMO

In ultrasound/computed tomography (CT) fusion images, ultrasound allows visualization of the target in real time. CT provides a navigation for ultrasound scanning and improves the overview in areas of limited visualization with ultrasound. This study was performed to investigate the feasibility of ultrasound/CT fusion based on an electromagnetic tracking technique using external fiducial markers for canine ocular and periocular regions. In 7 Beagle dogs, contrast-enhanced CT images of the head were obtained with placing external fiducial markers over the frontal region and both sides of the forepaws of the dog. Ultrasonography was performed under a magnetic field by installing a position sensor in the linear probe, without changing the dog's position. The positions of the external fiducial markers were adjusted and matched, based on the CT images. The execution time of co-registration and the distance between the regions of interest and the co-registration points, the frontal bone, cornea, retina, and optic nerve, were estimated. Approximately 60% of external fiducial markers were properly recognized in all dogs. After adjustment, all external fiducial markers were precisely matched. The co-registration execution time was less than 1 min. The distances between the regions of interest and co-registration points were less than 3 mm in all dogs. The electromagnetic tracking technique using external fiducial markers was a simple and applicable method for fusion imaging of a canine head using real-time ultrasonography and CT. This technique can be useful for interventional procedures of retrobulbar and periorbital lesions.


Assuntos
Olho/diagnóstico por imagem , Marcadores Fiduciais/veterinária , Tomografia Computadorizada por Raios X/veterinária , Ultrassonografia/veterinária , Animais , Cães , Fenômenos Eletromagnéticos , Masculino , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos
6.
J Cardiothorac Surg ; 14(1): 149, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31426812

RESUMO

OBJECTIVES: The study aimed to retrospectively evaluate the success rate, utility, practicality and results of pre-operative CT (computed tomography)-guided semi-rigid single hook-wire placement and the pathology results of small pulmonary nodules (SPN). MATERIALS AND METHODS: Seventy-four patients with 81 small pulmonary nodules underwent CT-guided semi-rigid single hook wire localization consecutively between 2016 and 2017 were reviewed. VATS (video-assisted thoracoscopic surgery) resection of lung tissue containing each pulmonary nodule and were performed in the direction of hook wire. The success rate and utility of the localization, hook wire related complications, the histopathology of SPN are analyzed. RESULTS: The semi-rigid hook wire was performed successfully in all 81 small pulmonary nodules within mean time of 10 min (8-13 min, SD: 1.58 min). Compared with solid nodules, GGOs (ground-glass opacity) were more frequently malignant (p < 0.05), with an OR (odds ratio) 8.59 (95%CI, 0.967, 412.845). Of the pure GGOs, 9 (25%) nodules were classified as AIS, 10 (27.8%) nodules were classified as MIA and 22 (57.9%) of the mGGOs were lung cancer. According to multivariate analysis, the malignant hazard was as high as 6.533-fold higher in nodules with a size larger than 10 mm compared with those smaller than 10 mm. GGOs with tiny blood vessels showed a statistically significant correlation with malignancy. Surprisingly, no statistically significant difference in the incidence of lung cancer in age. No major complication occurred. CONCLUSIONS: Preoperative localization of small pulmonary nodules using semi-rigid single hook wire was found to be practical and safe, which allows for proper diagnosis. Incidental small pulmonary nodule, especially GGO larger than 10 mm needs to be taken seriously.


Assuntos
Marcadores Fiduciais , Neoplasias Pulmonares/cirurgia , Nódulos Pulmonares Múltiplos/cirurgia , Nódulo Pulmonar Solitário/cirurgia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/patologia , Período Pré-Operatório , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/patologia , Cirurgia Torácica Vídeoassistida , Carga Tumoral , Adulto Jovem
7.
Radiat Oncol ; 14(1): 124, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296231

RESUMO

BACKGROUND: Stereotactic ablative radiotherapy (SABR) is a treatment option for patients with early stage non-small cell lung cancer (NSCLC) and recurrent or oligometastatic disease who are not surgical candidates. Due to the continuous motion of tumors within the lungs, implementing a strategy to track the target lesion is crucial. One method is to place fiducial markers which the robotic SABR system is able to track during treatment. However, placing these markers in a manner that maximizes tracking efficacy can be challenging. Using a novel fiducial placement guidance system (FPGS) during fiducial deployment may offer a way to improve the quantity of fiducials tracked by the robotic SABR system. METHOD: This was an institutional, retrospective review identifying all patients who received robotic SABR for lung tumors from May 2015 until January 2017. The FPGS was instituted in May 2016. The median number of fiducials tracked and the rate of complication was compared between patients whose fiducials were placed using FPGS versus those that were not. RESULTS: A total of 128 patients with 147 treated lung lesions were identified. Of the lesions that utilized FPGS (n = 44), 28 had 2 tracked fiducials (63.6%), 14 had 3 (31.8%) and 2 had 4 (4.6%). Of the lesions treated without FPGS (n = 103), 5 had 1 tracked fiducial (4.9%), 91 had 2 (88.4%), 6 had 3 (5.8%), and 2 had 4 (1.9%). A significant improvement in the median number of fiducials tracked per fraction was observed for the lesions with fiducials placed using FPGS on Wilcoxon rank sum test (p < 0.001). The rate of complication was low and not statistically different between cohorts (p = 0.44). CONCLUSIONS: The FPGS can be used during the deployment of fiducial markers and may increase the number of fiducials tracked. TRIAL REGISTRATION: An exemption for this retrospective review was granted by the East Carolina University IRB under UMCIRB 15-001726.


Assuntos
Broncoscopia/métodos , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Marcadores Fiduciais , Neoplasias Pulmonares/cirurgia , Monitorização Fisiológica , Radiocirurgia/métodos , Mecânica Respiratória , Fenômenos Eletromagnéticos , Humanos , Movimento , Planejamento da Radioterapia Assistida por Computador/métodos , Técnicas de Imagem de Sincronização Respiratória , Estudos Retrospectivos
8.
AJR Am J Roentgenol ; 213(4): 953-957, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31166765

RESUMO

OBJECTIVE. The objective of this study was to evaluate the feasibility of using a magnetic seed system for preoperative localization of axillary lymph nodes in patients with breast cancer. MATERIALS AND METHODS. We performed a retrospective analysis that included patients with breast cancer who underwent preoperative magnetic seed localization of axillary lymph nodes at our institution between January 1, 2017, and January 1, 2019. Magseed (Endomag) is a nonradioactive inducible magnetic seed that is induced to become a magnet when under the influence of its detector in the operating room. Clinical history, prior axillary sampling and clip placement, and procedure details and surgical outcomes were determined from a search of our PACS and electronic medical records. RESULTS. Thirty-five patients (34 women and one man) composed our study cohort. The mean patient age was 56 years (range, 32-78 years). One patient underwent two separate consecutive localizations for two separate operations, and another patient had bilateral lesions, for a total of 37 axillary lymph node localizations. One case of seed misplacement occurred during the ultrasound-guided localization procedure, resulting in immediate placement of a second seed, for a total of 38 Magseeds placed. All seeds were placed under ultrasound guidance. The mean number of days from seed placement to surgery was 5 days (range, 0-31 days). Thirty-seven of 38 Magseeds (97%) were documented to be successfully retrieved in the operating room. CONCLUSION. Magseed localization appears to be a safe, nonradioactive way to accurately localize axillary lymph nodes preoperatively.


Assuntos
Axila/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Marcadores Fiduciais , Metástase Linfática/diagnóstico por imagem , Magnetismo , Adulto , Idoso , Axila/patologia , Neoplasias da Mama/patologia , Estudos de Viabilidade , Feminino , Humanos , Metástase Linfática/patologia , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Retrospectivos
9.
Int J Radiat Oncol Biol Phys ; 105(2): 432-439, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31201892

RESUMO

PURPOSE: Deep learning is an emerging technique that allows us to capture imaging information beyond the visually recognizable level of a human being. Because of the anatomic characteristics and location, on-board target verification for radiation delivery to pancreatic tumors is a challenging task. Our goal was to use a deep neural network to localize the pancreatic tumor target on kV x-ray images acquired using an on-board imager for image guided radiation therapy. METHODS AND MATERIALS: The network is set up in such a way that the input is either a digitally reconstructed radiograph image or a monoscopic x-ray projection image acquired by the on-board imager from a given direction, and the output is the location of the planning target volume in the projection image. To produce a sufficient number of training x-ray images reflecting the vast number of possible clinical scenarios of anatomy distribution, a series of changes were introduced to the planning computed tomography images, including deformation, rotation, and translation, to simulate inter- and intrafractional variations. After model training, the accuracy of the model was evaluated by retrospectively studying patients who underwent pancreatic cancer radiation therapy. Statistical analysis using mean absolute differences (MADs) and Lin's concordance correlation coefficient were used to assess the accuracy of the predicted target positions. RESULTS: MADs between the model-predicted and the actual positions were found to be less than 2.60 mm in anteroposterior, lateral, and oblique directions for both axes in the detector plane. For comparison studies with and without fiducials, MADs are less than 2.49 mm. For all cases, Lin's concordance correlation coefficients between the predicted and actual positions were found to be better than 93%, demonstrating the success of the proposed deep learning for image guided radiation therapy. CONCLUSIONS: We demonstrated that markerless pancreatic tumor target localization is achievable with high accuracy by using a deep learning technique approach.


Assuntos
Aprendizado Profundo , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/radioterapia , Radioterapia Guiada por Imagem/métodos , Conjuntos de Dados como Assunto , Marcadores Fiduciais , Humanos , Processamento de Imagem Assistida por Computador , Movimentos dos Órgãos , Pâncreas/diagnóstico por imagem , Radiografia
10.
J Appl Clin Med Phys ; 20(6): 53-59, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31054217

RESUMO

PURPOSE: We evaluated the setup accuracy of a three-degree-of-freedom fiducial marker (3DOF-FM)-based setup compared to a soft tissue (ST)-based setup in hypofractionated intensity-modulated radiotherapy (IMRT) for prostate cancer. MATERIALS AND METHODS: We analyzed the setup accuracy for 17 consecutive prostate cancer patients with three implanted FMs who underwent hypofractionated IMRT. The 3DOF-ST-based setup using cone-beam computed tomography (CT) was performed after a six DOF-bony structure (BS)-based setup using an ExacTrac x-ray system. The 3DOF-FM-based matching using the ExacTrac x-ray system was done during the BS- and ST-based setups. We determined the mean absolute differences and the correlation between the FM- and ST-based translational shifts relative to the BS-based setup position. The rotational mean shifts detected by the ExacTrac x-ray system were also evaluated. RESULTS: The mean differences in the anterior-posterior (AP), superior-inferior (SI), and left-right (LR) dimensions were 0.69, 0.0, and 0.30 mm, respectively. The Pearson correlation coefficients for both shifts were 0.92 for AP, 0.91 for SI, and 0.68 for LR. The percentages of shift agreements within 2 mm were 85% for AP, 93% for SI, and 99% for LR. The absolute values of rotational shifts were 0.1° for AP, 0.3°, and 1.2° for LR. CONCLUSIONS: The setup accuracy of the 3DOF-FM-based setup has the potential to be interchangeable with a ST-based setup. Our data are likely to be useful in clinical practice along with the popularization of the hypofractionated IMRT in prostate cancer.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Marcadores Fiduciais , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/metabolismo , Dosagem Radioterapêutica , Erros de Configuração em Radioterapia/prevenção & controle
11.
Ann Otol Rhinol Laryngol ; 128(10): 894-902, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31067988

RESUMO

OBJECTIVE: Navigation systems create a connection between imaging data and intraoperative situs, allowing the surgeon to consistently determine the location of instruments and patient anatomy during the surgical procedure. The best results regarding the target registration error (measurement uncertainty) are normally demonstrated using fiducials. This study aimed at investigating a new registration strategy for an electromagnetic navigation device. METHODS: For evaluation of an electromagnetic navigation system and comparison of registration with screw markers and automatic registration, we are calculating the target registration error in the region of the paranasal sinuses/anterior and lateral skull base with the use of an electromagnetic navigation system and intraoperative digital volume tomography (cone-beam computed tomography). We carried out 10 registrations on a head model (total n = 150 measurements) and 10 registrations on 4 temporal bone specimens (total n = 160 measurements). RESULTS: All in all, the automatic registration was easy to perform. For the models that were used, a significant difference between an automatic registration and the registration on fiducials was evident for just a limited number of screws. Furthermore, the observed differences varied in terms of the preferential registration procedure. CONCLUSION: The automatic registration strategy seems to be an alternative to the established methods in artificial and cadaver models of intraoperative scenarios. Using intraoperative imaging, there is an option to resort to this kind of registration as needed.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Campos Eletromagnéticos , Neuronavegação/instrumentação , Neuronavegação/métodos , Base do Crânio/cirurgia , Cirurgia Assistida por Computador/métodos , Parafusos Ósseos , Cadáver , Marcadores Fiduciais , Humanos , Modelos Anatômicos , Seios Paranasais/diagnóstico por imagem , Seios Paranasais/cirurgia , Interpretação de Imagem Radiográfica Assistida por Computador/instrumentação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Base do Crânio/diagnóstico por imagem , Titânio
12.
J Appl Clin Med Phys ; 20(6): 120-124, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31116478

RESUMO

PURPOSE: To develop an Eclipse plug-in (MLC_MODIFIER) that automatically modifies control points to expose fiducials obscured by MLC during VMAT, thereby facilitating tracking using periodic MV/kV imaging. METHOD: Three-dimensional fiducial tracking was performed during VMAT by pairing short-arc (3°) MV digital tomosynthesis (DTS) images to triggered kV images. To evaluate MLC_MODIFIER efficacy, two cohorts of patients were considered. For first 12 patients, plans were manually edited to expose one fiducial marker. Next for 15 patients, plans were modified using MLC_MODIFIER script. MLC_MODIFIER evaluated MLC apertures at appropriate angles for marker visibility. Angles subtended by control points were compressed and low-dose "imaging" control points were inserted and exposed one marker with 1 cm margin. Patient's images were retrospectively reviewed to determine rate of MV registration failures. Failure categories were poor DTS image quality, MLC blockage of fiducials, or unknown reasons. Dosimetric differences in rectum, bladder, and urethra D1 cc, PTV maximum dose, and PTV dose homogeneity (PTV HI) were evaluated. Statistical significance was evaluated using Fisher's exact and Student's t test. RESULT: Overall MV registration failures, failures due to poor image quality, MLC blockage, and unknown reasons were 33% versus 8.9% (P < 0.0001), 8% versus 6.4% (P < 0.05), 13.6% versus 0.1% (P < 0.0001), and 7.6% versus 2.4% (P < 0.0001) for manually edited and MLC_MODIFIER plans, respectively. PTV maximum and HI increased on average from unmodified plans by 2.1% and 0.3% (P < 0.004) and 22.0% and 3.3% (P < 0.004) for manually edited and MLC_MODIFIED plans, respectively. Changes in bladder, rectum, and urethra D1CC were similar for each method and less than 0.7%. CONCLUSION: Increasing fiducial visibility via an automated process comprised of angular compression of control points and insertion of additional "imaging" control points is feasible. Degradation of plan quality is minimal. Fiducial detection and registration success rates are significantly improved compared to manually edited apertures.


Assuntos
Marcadores Fiduciais , Imagem Molecular/normas , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/instrumentação , Radioterapia de Intensidade Modulada/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagem Tridimensional , Masculino , Movimento , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem/métodos , Estudos Retrospectivos
13.
Cancer Radiother ; 23(4): 334-341, 2019 Jul.
Artigo em Francês | MEDLINE | ID: mdl-31113755

RESUMO

The four-dimensional scannography, also called 4D-CT, was created in the early 2000s. This method enables the aquistion of CT-scans synchronised with the patient's breathing. It allows an anatomical observation depending on the time. Different systems have been marketed. They are commonly used in treatment planning. It allows to take into account respiratory motion, considering the changes of shape and position of the tumor and organs. In the age of new techniques and stereotactic irradiations, 4D-CT is a valuable tool for estimating the uncertainties associated with respiratory movements, This technique also presents some limitations, including artifacts. The quality of the examination can be degraded in some patients with irregular respiration. Here we propose a summary of this technique detailing its principle of operation, its advantages and its main limits.


Assuntos
Tomografia Computadorizada Quadridimensional/métodos , Respiração , Artefatos , Marcadores Fiduciais , Humanos , Planejamento da Radioterapia Assistida por Computador
14.
Australas Phys Eng Sci Med ; 42(2): 585-598, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31087231

RESUMO

Intrafraction motion review (IMR), a real-time 2D, motion management feature of the Varian Truebeam™ incorporates triggered imaging, automatic fiducial marker detection and automatic beam hold. With the increasing adoption of high dose per fraction stereotactic body radiotherapy (SBRT) this system provides a potential means to ensure treatment accuracy. The goal of this study was therefore to investigate and quantify key performance characteristics of IMR for prostate treatment guidance. Phantom experiments were performed with a custom Computerized Imaging Reference Systems, Inc (CIRS) pelvis phantom with implanted gold seeds and the Hexamotion™ 5D motion platform. The system accuracy was assessed statically and under typical prostate motion trajectories. The IMR functionality and marker detectability was tested under different anatomical conditions and with different imaging acquisition modes. Imaging dose for triggered imaging modes was determined using an ionisation chamber based on IPEMB dose calibration protocol for kV energies. For zero displacement, the IMR demonstrated submillimeter agreement with the known position. Similarly, dynamic motion differences between the IMR reported position and 2D trajectory displacement were within 1 mm. Static displacement in the anterior direction was reported by IMR as sinusoidal motion on the x-axis (kV angle). The 2D nature of IMR limits the ability to detect motion out of the plane of the kV image detector. Using typical clinical imaging settings, imaging dose determined at the patient surface was 2.58 mGy/frame and the corresponding IMR displayed dose was 2.63 mGy/frame. The methodology used was able to quantify the accuracy of the IMR system. The IMR was able to accurately and consistently report fiducial positions within the limitations inherent of a 2D system. IMR is fully integrated with the Truebeam system with an easy to use and efficient workflow and is clinically beneficial especially within the context of SBRT.


Assuntos
Movimento (Física) , Neoplasias da Próstata/radioterapia , Relação Dose-Resposta à Radiação , Marcadores Fiduciais , Humanos , Imagem Tridimensional , Masculino , Imagens de Fantasmas , Próstata/efeitos da radiação , Razão Sinal-Ruído
15.
J Appl Clin Med Phys ; 20(5): 109-119, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31004395

RESUMO

The aim of current work was to present a novel evaluation procedure implemented for checking the constancy of beam path accuracy of a CyberKnife system based on ArcCHECK. A tailor-made Styrofoam with four implanted fiducial markers was adopted to enable the fiducial tracking during beam deliveries. A simple two-field plan and an isocentric plan were created for determining the density override of ArcCHECK in MultiPlan and the constancy of beam path accuracy respectively. Correlation curves for all diodes involved in the study were obtained by analyzing the dose distributions calculated by MultiPlan after introducing position shifts in anteroposterior, superoinferior, and left-right directions. The ability of detecting systematic position error was also evaluated by changing the position of alignment center intentionally. The one standard deviation (SD) result for reproducibility test showed the RMS of 0.054 mm and the maximum of 0.263 mm, which was comparable to the machine self-test result. The mean of absolute value of position errors in the constancy test was measured to 0.091 mm with a SD of 0.035 mm, while the root-mean-square was 0.127 mm with a SD of 0.034 mm. All introduced systematic position errors range from 0.3 to 2 mm were detected successfully. Efficient method for evaluating the constancy of beam path accuracy of CyberKnife has been developed and proven to be sensitive enough for detecting a systematic drift of robotic manipulator. Once the workflow is streamlined, our proposed method will be an effective and easy quality assurance procedure for medical physicists.


Assuntos
Marcadores Fiduciais , Neoplasias/cirurgia , Imagens de Fantasmas , Garantia da Qualidade dos Cuidados de Saúde/normas , Radiocirurgia/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Algoritmos , Humanos , Modelos Estatísticos , Controle de Qualidade , Radiocirurgia/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Reprodutibilidade dos Testes
16.
Indian J Ophthalmol ; 67(5): 619-624, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31007221

RESUMO

Purpose: To compare the outcomes of active-fluidics based torsional phacoemulsification in diabetics and nondiabetics using a balanced tip. Methods: Two hundred and forty-eight patients undergoing senile cataract surgery using torsional phacoemulsification on an active-fluidics-based platform from December 2016 to August 2017 were included in this prospective, nonrandomized, interventional cohort study; of the 248 patients, 54 were controlled diabetics and 194 were nondiabetics. Intraoperative parameters such as cumulative dissipated energy (CDE), total ultrasound time, torsion usage time, torsion amplitude, aspiration time, and fluid usage were documented and compared. Endothelial cell loss (ECL) and central corneal thickness (CCT) were evaluated at 1 month postoperatively. Results: Diabetics and nondiabetics did not differ in CDE, total ultrasound time, torsion amplitude, aspiration time, fluid usage, endothelial cell count, and CCT. ECL on Day 1 (10.2 ± 8.0%) and Day 30 (11.05 ± 8.3%) were significantly higher in diabetics (P = 0.025 and P = 0.045, respectively). There was an increase in CCT on Day 1 (P = 0.018), which settled by Day 30. Grade 4 cataracts in diabetics had significantly higher CCT at Day 1 (P = 0.032) and Day 30 (P = 0.007). In the diabetic subgroup, Grades 3 and 4 cataracts required lower CDE (P < 0.001) and Grade 4 cataracts showed higher ECL than others till 1 month of follow-up (P < 0.05). Conclusion: Intraoperative and postoperative parameters after torsional phacoemulsification are comparable in diabetics and nondiabetics. Endothelial changes and pachymetry may be related to the grade of cataract in diabetics.


Assuntos
Catarata/complicações , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Marcadores Fiduciais , Facoemulsificação/métodos , Complicações Pós-Operatórias/epidemiologia , Acuidade Visual , Epitélio Posterior/patologia , Feminino , Seguimentos , Humanos , Incidência , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Estudos Prospectivos
17.
Ther Adv Respir Dis ; 13: 1753466619841234, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30958102

RESUMO

BACKGROUND: Fiducial markers (FMs) help direct stereotactic body radiation therapy (SBRT) and localization for surgical resection in lung cancer management. We report the safety, accuracy, and practice patterns of FM placement utilizing electromagnetic navigation bronchoscopy (ENB). METHODS: NAVIGATE is a global, prospective, multicenter, observational cohort study of ENB using the superDimension™ navigation system. This prospectively collected subgroup analysis presents the patient demographics, procedural characteristics, and 1-month outcomes in patients undergoing ENB-guided FM placement. Follow up through 24 months is ongoing. RESULTS: Two-hundred fifty-eight patients from 21 centers in the United States were included. General anesthesia was used in 68.2%. Lesion location was confirmed by radial endobronchial ultrasound in 34.5% of procedures. The median ENB procedure time was 31.0 min. Concurrent lung lesion biopsy was conducted in 82.6% (213/258) of patients. A mean of 2.2 ± 1.7 FMs (median 1.0 FMs) were placed per patient and 99.2% were accurately positioned based on subjective operator assessment. Follow-up imaging showed that 94.1% (239/254) of markers remained in place. The procedure-related pneumothorax rate was 5.4% (14/258) overall and 3.1% (8/258) grade ⩾ 2 based on the Common Terminology Criteria for Adverse Events scale. The procedure-related grade ⩾ 4 respiratory failure rate was 1.6% (4/258). There were no bronchopulmonary hemorrhages. CONCLUSION: ENB is an accurate and versatile tool to place FMs for SBRT and localization for surgical resection with low complication rates. The ability to perform a biopsy safely in the same procedure can also increase efficiency. The impact of practice pattern variations on therapeutic effectiveness requires further study. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02410837.


Assuntos
Broncoscopia/métodos , Fenômenos Eletromagnéticos , Marcadores Fiduciais , Neoplasias Pulmonares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia/métodos , Estudos de Coortes , Endossonografia/métodos , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Pneumotórax/epidemiologia , Pneumotórax/etiologia , Estudos Prospectivos , Radiocirurgia/métodos , Insuficiência Respiratória/epidemiologia , Insuficiência Respiratória/etiologia
18.
Magn Reson Imaging ; 60: 68-75, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30959177

RESUMO

PURPOSE: To develop an off-resonant frequency filtered method to selectively differentiate between implanted gold fiducial markers and platinum coated brachytherapy seeds. MATERIALS AND METHODS: The magnetic susceptibilities for gold fiducial markers and brachytherapy seeds differ in magnitude and also in their signs, resulting in B0-field inhomogeneity patterns with opposite main lobes. A pulse sequence used to localize brachytherapy seeds with positive contrast, centre-out radial sampling with off-resonance reception (co-RASOR), was used to reconstruct images with a range of off-resonant frequency offsets. The proposed method utilizes two frequency filters to selectively reconstruct maximum intensity projections through band-pass regions where each seed has its maximal localized hyperintensity. Seeds were simulated and then placed in gel and tissue phantoms to validate the technique using orthogonal 2D slices with seeds both parallel and perpendicular to the B0-field. RESULTS: Dual-plane 2D co-RASOR sequences were reconstructed off-resonance with applied frequency filters to create two projections displaying each seed, which were then colour-coded to negative and positive frequencies. Phantom validation showed that each seed contains its maximal CNR in opposing frequency regions as predicted. Local maxima can also appear in both negative and positive frequency regions. The relative difference between the signal of each seed and these local maxima ranged from 1.19 to 3.73, and an image threshold was determined in all cases. Tissue validation showed the technique differentiates seeds correctly and is limited by the hyperintensity patterns observed in the co-RASOR method. CONCLUSIONS: Dual-plane co-RASOR offers sub-millimetre positive contrast from implanted seeds that contain unique off-resonant frequency maxima, which frequency filters can selectively differentiate.


Assuntos
Braquiterapia/instrumentação , Braquiterapia/métodos , Marcadores Fiduciais , Ouro/química , Imagens de Fantasmas , Platina/química , Neoplasias da Próstata/diagnóstico por imagem , Ágar , Cor , Simulação por Computador , Meios de Contraste , Humanos , Imagem por Ressonância Magnética , Masculino , Modelos Teóricos , Próteses e Implantes , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X
19.
Int J Radiat Oncol Biol Phys ; 104(5): 1066-1073, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31002941

RESUMO

PURPOSE: High-dose-rate brachytherapy boost plus external beam radiation therapy is an established option for intermediate-risk prostate cancer (PCa). Stereotactic body radiation therapy (SBRT) boost can potentially mimic high-dose-rate boost and could be a viable alternative. Here we report the long-term outcomes of a phase 1 dose-escalation trial of single-fraction SBRT boost. METHODS AND MATERIALS: Patients had intermediate-risk PCa and were accrued to 3 different SBRT single-fraction dose-level cohorts (10 Gy, 12.5 Gy, and 15 Gy). All received supplemental radiation therapy afterwards (37.5 Gy in 15 fractions). Three gold fiducials were implanted for image guidance. Patients were simulated and treated with a foley catheter and intrarectal balloon. A T2 magnetic resonance imaging scan was used for contouring, and a cine magnetic resonance imaging scan was used to calculate patient-specific internal target volume margins. Toxicity and quality-of-life data were collected using Common Terminology Criteria for Adverse Events v3.0 and the Expanded Prostate Cancer Index Composite. RESULTS: 30 patients were accrued, 10 in each cohort. Median follow-up was 72 months. 60% had unfavorable intermediate-risk PCa. Two patients in the 15 Gy cohort developed late grade ≥3 gastrointestinal and genitourinary toxicity, with 1 patient suffering from a grade-4 rectal fistula after a rectal ulcer was biopsied repeatedly. Two patients had biochemical failure. Median PSA nadir was 0.4 ng/mL with 10 Gy, 0.09 ng/mL with 12.5 Gy and 0.07 ng/mL with 15 Gy. Median PSA at 4 years as well as proportion achieving a nadir <0.2 ng/mL improved significantly with higher doses. There was no significant change in quality of life from baseline in any of the domains, and the minimal clinically important change was not statistically different between the 3 cohorts. CONCLUSIONS: Other than a grade 4 toxicity, which may in part be due to repeated biopsies of a rectal ulcer, single-fraction SBRT boost was feasible and well tolerated. Larger studies are warranted to better document the outcomes of such an approach.


Assuntos
Neoplasias da Próstata/radioterapia , Radiocirurgia/métodos , Idoso , Braquiterapia/métodos , Estudos de Coortes , Estudos de Viabilidade , Marcadores Fiduciais , Humanos , Calicreínas/sangue , Masculino , Gradação de Tumores , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Radiocirurgia/efeitos adversos , Dosagem Radioterapêutica , Reirradiação/métodos , Fístula Retal/etiologia , Risco
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