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2.
Clin Transl Radiat Oncol ; 31: 8-13, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34504959

RESUMEN

BACKGROUND: Patients diagnosed with locoregionally advanced head and neck squamous cell carcinoma (LAHNSCC) regularly undergo staging with 18F-FDG PET/CT in our center. In cases of delays in radiotherapy (RT) planning CT more than 4 weeks after initial PET/CT or clinically suspected progress, PET/CT is repeated for restaging and as an RT planning reference. Our aim was to determine the impact of second-look PET/CT on stage migration, treatment change and RT planning. METHODS: Consequent treatment changes were categorized as minor and major. Minor changes were defined as PET/CT-based modifications of RT plans, e.g., the addition of anatomical compartments, changes in high- and low-risk dose levels or both. Major changes included changes from curative to palliative treatment intent and alterations of interdisciplinary treatment plans, such as the addition of induction chemotherapy, switch to primary surgery, no treatment and/or the necessity of additional diagnostic work-up resulting in the postponement or cancellation of treatment. RESULTS: Thirty-two newly diagnosed LAHNSCC patients who were treated between 2014 and 2018 underwent second-look PET/CT (median interval 42.5 days). Second-look PET/CT led to locoregional and distant upstaging in 3/32 and 1/32 patients, respectively. In 1/32 patients (3%), second-look PET/CT led to a palliative approach with systemic treatment. New lymph node metastases were discovered in 16 patients, 6 of whom also showed significant progression of the primary tumor, resulting in minor changes in 16 of the remaining 31 patients (52%) who were treated curatively. CONCLUSION: If RT treatment planning of LAHNSCC was delayed by more than 4 weeks after initial PET/CT staging or when progression was clinically suspected, a second look at 18FDG-PET/CT was performed. This led to changes in treatment planning in more than half of the cases, which is expected to directly influence oncologic outcomes.

3.
JBJS Case Connect ; 11(2)2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-34101664

RESUMEN

CASE: A 70-year-old female patient underwent total hip arthroplasty (HA) using a stem cemented line-to-line without centralizer. Postoperatively, she complained of load-dependent thigh pain. Conventional radiographs identified cortical overload because of a distal cement mantle discontinuity at the level of the stem's tip, confirmed by single-photon emission computed tomography/computed tomography scan (SPECT/CT). After cement-in-cement revision using a stem with centralizer, pain ceased rapidly. The cortical overload disappeared, as confirmed on a following SPECT/CT performed for low back pain. CONCLUSION: In HA, the stem's tip may cause overload on the bone's cortex if the cement mantle is incomplete. Implanting a stem with centralizer avoids or cures this.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/métodos , Cementación/métodos , Femenino , Prótesis de Cadera/efectos adversos , Humanos , Diseño de Prótesis , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único
4.
Nuklearmedizin ; 60(1): 7-9, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33080626

RESUMEN

While FDG-PET imaging of the brain for the differential diagnosis of dementia has been covered by the compulsory health insurance in Switzerland for more than a decade, beta-amyloid-PET just recently has been added to the catalogue of procedures that have been cleared for routine use, provided that a set of appropriate use criteria (AUC) be followed. To provide guidance to dementia care practitioners, the Swiss Society of Nuclear Medicine and the Swiss Memory Clinics jointly report a mini-review on beta-amyloid-PET and discuss the AUC set into effect by the Swiss Federal Office of Public Health, as well as their application and limitations.


Asunto(s)
Amiloide/metabolismo , Demencia/diagnóstico por imagen , Demencia/metabolismo , Medicina Nuclear , Sociedades Médicas , Humanos , Suiza
5.
Case Rep Oncol ; 13(2): 729-732, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32774266

RESUMEN

Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) are established effective therapies in patients with ALK-rearranged advanced non-small-cell lung cancer (NSCLC). Upon progressive disease, patients normally receive a subsequent ALK TKI. However, when disease progression occurs in a limited number of sites, an oligoprogressive approach is a treatment option. In our case, FDG-PET/CT scan detected a progressive site in a patient with ceritinib therapy. Biopsy of the lesion was not possible because of its location. Progression was therefore confirmed by liquid biopsy with identification of the resistant subclone ALK G1202R. Definitive radiotherapy of the progressive site led to the disappearance of the ALK-resistant mutation. Meanwhile, ceritinib therapy was continued. The absence of disease both on repeated imaging and liquid biopsy indicates that eradication of a resistant subclone with an oligoprogressive treatment approach might be possible.

6.
EJNMMI Phys ; 7(1): 22, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32323035

RESUMEN

BACKGROUND: For multicenter clinical studies, PET/CT and SPECT/CT scanners need to be validated to ensure comparability between various scanner types and brands. This validation is usually performed using hollow phantoms filled with radioactive liquids. In recent years, 3D printing technology has gained increasing popularity for manufacturing of phantoms, as it is cost-efficient and allows preparation of phantoms of almost any shape. So far, however, direct 3D printing with radioactive building materials has not yet been reported. The aim of this work was to develop a procedure for preparation of 99mTc-containing building materials and demonstrate successful application of this material for 3D printing of several test objects. METHOD: The desired activity of a [99mTc]pertechnetate solution eluted from a 99Mo/99mTc-generator was added to the liquid 3D building material, followed by a minute amount of trioctylphosphine. The resulting two-phase mixture was thoroughly mixed. Following separation of the phases and chemical removal of traces of water, the radioactive building material was diluted with the required volume of non-radioactive building material and directly used for 3D printing. RESULTS: Using our optimized extraction protocol with trioctylphosphine as complex-forming phase transfer agent, technetium-99m was efficiently transferred from the aqueous 99Mo/99mTc-generator eluate into the organic liquid resin monomer. The observed radioactivity concentration ratio between the organic phase and the water phase was > 2000:1. The radioactivity was homogeneously distributed in the liquid resin monomer. We did not note differences in the 3D printing behavior of the radiolabeled and the unlabeled organic liquid resin monomers. Radio-TLC and SPECT studies showed homogenous 2D and 3D distribution of radioactivity throughout the printed phantoms. The radioactivity was stably bound in the resin, apart from a small amount of surface-extractable radioactivity under harsh conditions (ethanol at 50 °C). CONCLUSIONS: 3D printing of radioactive phantoms using 99mTc-containing building materials is feasible. Compared to the classical fillable phantoms, 3D printing with radioactive building materials allows manufacturing of phantoms without cold walls and in almost any shape. Related procedures with longer-lived radionuclides will enable production of phantoms for scanner validation and quality control.

7.
PLoS One ; 15(3): e0229560, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32176698

RESUMEN

PURPOSE: Image texture is increasingly used to discriminate tissues and lesions in PET/CT. For quantification or in computer-aided diagnosis, textural feature analysis must produce robust and comparable values. Because statistical feature values depend on image count statistics, we investigated in depth the stability of Haralick features values as functions of acquisition duration, and for common image resolutions and reconstructions. METHODS: A homogeneous cylindrical phantom containing 9.6 kBq/ml Ge-68 was repeatedly imaged on a Siemens Biograph mCT, with acquisition durations ranging from three seconds to three hours. Images with 1.5, 2, and 4 mm isometrically spaced voxels were reconstructed with filtered back-projection (FBP), ordered subset expectation maximization (OSEM), and the Siemens TrueX algorithm. We analysed Haralick features derived from differently quantized (3 to 8-bit) grey level co-occurrence matrices (GLCMs) as functions of exposure E, which we defined as the product of activity concentration in a volume of interest (VOI) and acquisition duration. The VOI was a 50 mm wide cube at the centre of the phantom. Feature stability was defined for df/dE → 0. RESULTS: The most stable feature values occurred in low resolution FBPs, whereas some feature values from 1.5 mm TrueX reconstructions ranged over two orders of magnitude. Within the same reconstructions, most feature value-exposure curves reached stable plateaus at similar exposures, regardless of GLCM quantization. With 8-bit GLCM, median time to stability was 16 s and 22 s for FBPs, 18 s and 125 s for OSEM, and 23 s, 45 s, and 76 s for PSF reconstructions, with longer durations for higher resolutions. Stable exposures coincided in OSEM and TrueX reconstructions with image noise distributions converging to a Gaussian. In FBP, the occurrence of stable values coincided the disappearance of negatives image values in the VOI. CONCLUSIONS: Haralick feature values depend strongly on exposure, but invariance exists within defined domains of exposure. Here, we present an easily replicable procedure to identify said stable exposure domains, where image noise does not substantially add to textural feature values. Only by imaging at predetermined feature-invariant exposure levels and by adjusting exposure to expected activity concentrations, can textural features have a quantitative use in PET/CT. The necessary exposure levels are attainable by modern PET/CT systems in clinical routine.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Algoritmos , Animales , Fluorodesoxiglucosa F18 , Humanos , Fantasmas de Imagen/estadística & datos numéricos , Tomografía Computarizada por Tomografía de Emisión de Positrones/normas , Tomografía Computarizada por Tomografía de Emisión de Positrones/estadística & datos numéricos , Tomografía de Emisión de Positrones/métodos , Radiofármacos
8.
Open Forum Infect Dis ; 6(4): ofz130, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31008142

RESUMEN

Cardiac implantable electronic device-related infection is clinically challenging. Curative treatment commonly includes system removal. A case caused by Granulicatella adiacens occurred in a 32-year-old woman. Clinical course, literature review, and biofilm investigations enabled successful antibiotic management without system removal.

9.
Clin Oral Investig ; 23(12): 4213-4222, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30806799

RESUMEN

OBJECTIVES: Therapy of osteomyelitis and osteonecrosis very often requires surgery. Proper preoperative radiological evaluation of a lesion's localization and extent is a key in planning surgical bone resection. This study aims to assess the differences between single-photon emission computed tomography and cone beam computed tomography when detecting an osteomyelitis/osteonecrosis lesion as well as the lesion's qualitative parameters, extent, and localization. MATERIAL AND METHODS: Identification of candidates was performed retrospectively following a search for patients with histologically or clinically confirmed osteomyelitis or osteonecrosis. They were matched with a list of patients whose disease extent and localization had been evaluated using single-photon emission computed tomography and cone beam computed tomography in the context of clinical investigations. Subsequently, two experienced examiners for each imaging technique separately performed de novo readings. Detection rate, localization, extent, and qualitative parameters of a lesion were then compared. RESULTS: Twenty-one patients with mandibular osteomyelitis and osteonecrotic lesions were included. Cone beam computed tomography detected more lesions than single-photon emission computed tomography (25 vs. 23; 100% vs. 92%). Cone beam computed tomography showed significantly greater depth, area, and volume, whereas length and width did not differ statistically between the two groups. CONCLUSION: Both single-photon emission computed tomography and cone beam computed tomography could sensitively detect osteomyelitis/osteonecrosis lesions. Only single-photon emission computed tomography showed metabolic changes, whereas cone beam computed tomography seemed to display anatomic morphological reactions more accurately. The selection of the most adequate three-dimensional imaging and the correct interpretation of preoperative imaging remains challenging for clinicians. CLINICAL RELEVANCE: In daily clinical practice, three-dimensional imaging is an important tool for evaluation of osteomyelitis/osteonecrosis lesions. In this context, clinicians should be aware of differences between single-photon emission computed tomography and cone beam computed tomography when detecting and assessing an osteomyelitis/osteonecrosis lesion, especially if a surgical bone resection is planned.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Mandíbula/diagnóstico por imagen , Osteomielitis/diagnóstico por imagen , Osteonecrosis/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
J Nucl Med ; 2018 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-29880508

RESUMEN

Rationale: (18F)fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) for staging Hodgkin lymphoma may allow for accurate and reliable assessment of the metabolic tumour volume (MTV) as baseline risk factor. Our aim was to analyse the prognostic impact of MTV measurements, obtained by different means in advanced-stage Hodgkin lymphoma patients treated within the German Hodgkin Study Group HD18 trial. Methods: Within the German Hodgkin Study Group trial HD18, 310 patients underwent 18F-FDG PET/CT scanning for staging which was available to the central review panel for quantitative analysis. We calculated the MTV by four different thresholding methods and performed receiver operating characteristic (ROC) analysis to evaluate the potential for prediction of early response determined by PET after two cycles (PET-2) dose-escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (eBEACOPP). Logistic regression was used to evaluate its prognostic value concerning progression-free survival (PFS) and overall survival (OS). Results: All different MTV calculations used predicted PET-2 response to a moderate and comparable degree (area under the curve = 0.62-0.63, P = 0.01-0.06). With none of the measuring methods did the ROC curves point to any unique cut-off values, but indicated a wide range of possible cut-offs. However, none of the MTV measurements was prognostic for PFS (Hazard ratio 1.2-1.5, P = 0.15-0.52) or OS (Hazard ratio 1.0-1.5, P = 0.95 - 0.27). Conclusion: Baseline MTV as determined by different means, is a predictive factor for early response to eBEACOPP after two cycles. However, value as a prognostic factor after highly effective PET-2 adapted treatment strategy could not be observed.

11.
Med Phys ; 44(7): 3761-3766, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28494090

RESUMEN

PURPOSE: Avoiding measurement variability from 18 F phantom preparation by using 68 Ge/68 Ga phantoms for the determination of 18 F recovery curves (RC) in clinical quality assurance measurements and for PET/CT site qualification in multicentre clinical trials. METHODS: RCs were obtained from PET/CT measurements of seven differently sized phantom spheres filled either with 18 F or with 68 Ga. RCs for the respective other isotope were then determined by two different methods: In the first method, images were convolved with positron range transconvolution functions derived from positron annihilation distributions found in literature. This method generated recasted images matching images using the respective other isotope. In the second method, the PET/CT system's isotope independent (intrinsic) point spread function was determined from said phantom measurements and convolved with numerical representations simulating hot spheres filled with the respective other isotope. These simulations included the isotope specific positron annihilation distributions. Recovered activity concentrations were compared between recasted images, simulated images, and the originally acquired images. RESULTS: 18 F and 68 Ga recovery was successfully determined from image acquisitions of the respective opposite isotope as well as from the simulations. 68 Ga RCs derived from 18 F data had a normalized root-mean-square deviation (NRMSD) from real 68 Ga measurements of 0.019% when using the first method and of 0.008% when using the second method. 18 F RCs derived from 68 Ga data had a NRMSD from real 18 F measurements of 0.036% when using the first method and of 0.038% when using the second method. CONCLUSIONS: Applying the principles of transconvolution, 18 F RCs can be recalculated from 68 Ga phantom measurements with excellent accuracy. The maximal additionally introduced error was below 0.4% of the error currently accepted for RCs in the site qualification of multicentre clinical trials by the EARL program of the European Association of Nuclear Medicine (EANM). Therefore, our methods legitimately allow for the use of long-lived solid state 68 Ge/68 Ga phantoms instead of manually prepared 18 F phantoms to characterize comparability of 18 F measurements across different imaging sites or of longitudinal 18 F measurements at a single PET/CT system.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Electrones , Humanos , Tomografía de Emisión de Positrones
13.
Med Phys ; 44(4): 1558-1562, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28206679

RESUMEN

PURPOSE: To determine the thyroid clearance effective half-life T with a common handheld electronic dosimeter (ED) in patients undergoing radioiodine treatment for hyperthyroidism. METHODS: Dose rates from 12 inpatients were measured daily with an ED and with a clinical uptake counter. The ED was attached to the patient with two different setups, one using a cervical collar and another employing a neck strap. Estimation of T was performed by linear regression analysis of the log of both the ED and the uptake counter measurements versus time. The latter provided the reference data. RESULTS: Based on repeated neck strap dose rate measurements, individual Ts were determined with clinically required accuracy. The mean difference from the reference method equaled to -0.09 ± 0.35 days. CONCLUSIONS: Determination of individual T is feasible with a common handheld ED using the simple and easy to instruct neck strap measurement setup. This simple method complements stationary uptake counter measurements and thus may improve the accuracy of radioiodine treatment planning by adding an individual T for dose calculation.


Asunto(s)
Equipos y Suministros Eléctricos , Radiometría/instrumentación , Glándula Tiroides/metabolismo , Semivida , Humanos , Hipertiroidismo/metabolismo , Hipertiroidismo/radioterapia , Radioisótopos de Yodo/metabolismo , Radioisótopos de Yodo/uso terapéutico , Glándula Tiroides/efectos de la radiación
14.
Med Phys ; 43(10): 5767, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27782715

RESUMEN

PURPOSE: A PET/CT system's imaging capabilities are best described by its point spread function (PSF) in the spatial domain or equivalently by its modulation transfer function (MTF) in the spatial frequency domain. Knowing PSFs or MTFs is a prerequisite for many numerical methods attempting to improve resolution and to reduce the partial volume effect. In PET/CT, the observed PSF is a convolution of the system's intrinsic imaging capabilities including image reconstruction (PSF0) and the positron range function (PRF) of the imaged ß+ emitting isotope. A PRF describes the non-Gaussian distribution of ß+ annihilation events around a hypothetical point source. The main aim was to introduce a new method for determining a PET/CT system's intrinsic MTF (MTF0) from phantom measurements of hot spheres independently of the ß+ emitting isotope used for image acquisition. Secondary aim was to examine non-Gaussian and nonlinear MTFs of a modern iterative reconstruction algorithm. METHODS: PET/CT images of seven phantom spheres with volumes ranging from 0.25 to 16 ml and filled either with 18F or with 68Ga were acquired and reconstructed using filtered back projection (FBP). MTFs were modeled with linear splines. The spline fit iteratively minimized the mean squared error between the acquired PET/CT image and a convolution of the thereof derived PSF with a numerical representation of the imaged hot phantom sphere. For determining MTF0, the numerical sphere representations were convolved with a PRF, simulating a fill with either 18F or 68Ga. The MTFs determined by this so-called MTF fit method were compared with MTFs derived from point source measurements and also compared with MTFs derived with a previously published PSF fit method. The MTF fit method was additionally applied to images reconstructed by a vendor iterative algorithm with PSF recovery (Siemens TrueX). RESULTS: The MTF fit method was able to determine 18F and 68Ga dependent MTFs and MTF0 from FBP reconstructed images. Root-mean-square deviation between fit determined MTFs and point source determined MTFs ranged from 0.023 to 0.039. MTFs from Siemens TrueX reconstructions varied with size of the imaged sphere. CONCLUSIONS: MTF0 can be determined regardless of the imaged isotope, when using existing PRF models for the MTF fit method presented. The method proves that modern iterative PET/CT reconstruction algorithms have nonlinear imaging properties. This behaviour is not accessible by point source measurements. MTFs resulting from these clinically applied algorithms need to be estimated from objects of similar geometry to those intended for clinical imaging.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Fantasmas de Imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/instrumentación , Isótopos
15.
Hematol Oncol ; 34(3): 133-9, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25689832

RESUMEN

Early relapse is common in patients with mantle cell lymphoma (MCL) highlighting the unmet need for further improvement of therapeutic options for these patients. CD20 inhibition combined with induction chemotherapy as well as consolidation with high-dose chemotherapy (HDCT) is increasingly considered cornerstones within current therapy algorithms of MCL whereas the role of radioimmunotherapy is unclear. This retrospective single center study compared 46 consecutive MCL patients receiving HDCT in first or second remission. Thirty-five patients had rituximab and BEAM (R-BEAM), and 11 patients received ibritumomab tiuxetan (Zevalin®), an Yttrium-90 labeled CD20 targeting antibody, prior to BEAM (Z-BEAM) followed by autologous stem cell transplantation (ASCT). We observed that the 5-year overall survival (OS) in the R-BEAM and Z-BEAM groups was 55% and 71% (p = 0.288), and the 4-year progression free survival (PFS) was 32% and 41%, respectively (p = 0.300). There were no treatment related deaths in both groups, and we observed no differences in toxicities, infection rates or engraftment. Our data suggest that the Z-BEAM conditioning regimen followed by ASCT is well tolerated, but was not associated with significantly improved survival compared to R-BEAM. Copyright © 2015 John Wiley & Sons, Ltd.


Asunto(s)
Algoritmos , Anticuerpos Monoclonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Linfoma de Células del Manto , Rituximab/administración & dosificación , Trasplante de Células Madre , Acondicionamiento Pretrasplante , Adulto , Anciano , Autoinjertos , Carmustina/administración & dosificación , Citarabina/administración & dosificación , Supervivencia sin Enfermedad , Femenino , Humanos , Linfoma de Células del Manto/mortalidad , Linfoma de Células del Manto/terapia , Masculino , Melfalán/administración & dosificación , Persona de Mediana Edad , Podofilotoxina/administración & dosificación , Tasa de Supervivencia
16.
Leuk Res ; 39(3): 307-10, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25616614

RESUMEN

The addition of anti-CD20 antibodies to high intensity polychemotherapy regimens has improved response and survival rates in newly diagnosed patients with Burkitt lymphoma (BL). However, the role of additional anti-CD20 directed radioimmunotherapy for consolidation of first remission (CR1) has not been reported so far in BL patients receiving rituximab during first-line treatment. We compared five BL patients receiving Y-90-IT radioimmunotherapy consolidation in CR1 to 22 consecutive BL patients without consolidation. We observed that Y-90-IT treatment was associated with clinically relevant myelosuppression. After a median follow-up of 50 months, none of the patients with Y-90-IT treatment relapsed, and no patient died. In contrast, one patient (4.5%) in the non-Y-90-IT group relapsed (50 months-PFS 95.5%; p=0.6336), and one patient died (50 months-OS 95.5%; p=0.6171). In conclusion, our data suggest that survival rates are excellent and equal in rituximab pretreated BL patients with or without Y-90-IT consolidation in first remission.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Linfoma de Burkitt/terapia , Recurrencia Local de Neoplasia/terapia , Radioinmunoterapia , Radioisótopos de Itrio/uso terapéutico , Adolescente , Adulto , Anciano , Linfoma de Burkitt/inmunología , Linfoma de Burkitt/mortalidad , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/inmunología , Recurrencia Local de Neoplasia/mortalidad , Estadificación de Neoplasias , Pronóstico , Inducción de Remisión , Estudios Retrospectivos , Tasa de Supervivencia , Adulto Joven
17.
Cardiovasc Intervent Radiol ; 38(4): 1025-30, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25373797

RESUMEN

We herein present a patient undergoing selective internal radiation therapy with an almost normal lung shunt fraction of 11.5%, developing histologically proven radiation pneumonitis. Due to a predominance of pulmonary consolidations in the right lower lung and its proximity to a large liver metastases located in the dome of the right liver lobe a Monte Carlo simulation was performed to estimate the effect of direct irradiation of the lung parenchyma. According to our calculations direct irradiation seems negligible and RP is almost exclusively due to ectopic draining of radioactive spheres.


Asunto(s)
Leiomiosarcoma/radioterapia , Neoplasias Hepáticas/radioterapia , Neoplasias Primarias Secundarias/radioterapia , Neumonitis por Radiación/diagnóstico por imagen , Neoplasias Vasculares/patología , Adulto , Biopsia , Femenino , Estudios de Seguimiento , Humanos , Leiomiosarcoma/patología , Leiomiosarcoma/cirugía , Neoplasias Hepáticas/secundario , Pulmón/diagnóstico por imagen , Pulmón/patología , Microesferas , Método de Montecarlo , Neumonitis por Radiación/patología , Tomografía Computarizada por Rayos X , Neoplasias Vasculares/cirugía , Radioisótopos de Itrio/uso terapéutico
18.
Cardiol Res Pract ; 2014: 179632, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25089213

RESUMEN

Background. Contrast-enhanced computed tomography is commonly acquired before radiofrequency catheter ablation (RFCA) for atrial fibrillation (AFib) to guide the procedure. We analyzed pulmonary vein (PV) ostial diameter and volumes on a high-definition 64-slice CT (HDCT) scanner in patients with AFib prior to RFCA. Methods and Results. This retrospective study included 50 patients (mean age 60.2 ± 11.4 years, 30 males) undergoing cardiac HDCT scanning before RFCA for drug refractory AFib and 50 age-, BMI-, and sex-matched controls with normal sinus rhythm undergoing HDCT. PV ostial diameter and volume were measured and calculated using a semiautomatic calliper tool. Total ostial PV volume was significantly increased in patients with AFib as compared to controls (P < 0.005). Similarly, total ostial PV diameter was significantly increased in AFib compared to controls (P < 0.001). In AFib, the largest PV volume and diameters were measured in right superior PV (P < 0.05 versus controls). The difference in PV volume between patients and controls was most pronounced in right superior PVs (P = 0.015). Right middle PVs were found more often in patients with AFib (16/50; 32%) than in normal subjects (7/50; 14%). Conclusion. Enlargement of PV ostial area and enlargement of volume are frequent findings in patients with drug refractory AFib. These parameters may add to the risk stratification for AFib recurrence following RFCA.

19.
Int J Cardiovasc Imaging ; 30(6): 1191-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24771130

RESUMEN

Gender- and age-related changes of left ventricular (LV) function and dimensions have not been elucidated in a large population by gated SPECT. Thus, the aim of this study was to derive male and female reference limits for left ventricular functional parameters, and determine the effect of age on LV dimensions and systolic function for this imaging modality. 1,639 (53% males) subjects without cardiovascular disease who underwent cardiac SPECT between January 2002 and June 2012 were included in this study. Mean age at presentation was 61 ± 12 years (range 18-92 years). A significant effect of age (p = 0.011) and gender (p < 0.0001) on resting LV ejection fraction (LVEF) was observed, with an increase in LVEF with age being more pronounced in women (ΔB-coefficient: -0.088, p = 0.011). Overall, mean LVEF was higher in women compared to men (70.3 ± 8.6% vs. 64.4 ± 7.5%, p < 0.0001). LVEF after pharmacological stress with adenosine was significantly lower than at rest in both women and men (∆LVEF = 1.1% in males and ∆LVEF = 1.6% in females, p = 0.01), which was the result of a significant increase in end-systolic volume after stress (p = 0.0001). With advancing age an increase in LVEF was observed that was more pronounced in women than in men. These findings indicate that the evaluation of cardiac function and volumes of patients by gated SPECT should consider age- and gender-matched normative values.


Asunto(s)
Tomografía Computarizada por Emisión de Fotón Único Sincronizada Cardíaca , Ventrículos Cardíacos/diagnóstico por imagen , Imagen de Perfusión Miocárdica/métodos , Función Ventricular Izquierda , Adenosina , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Tomografía Computarizada por Emisión de Fotón Único Sincronizada Cardíaca/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica , Imagen de Perfusión Miocárdica/normas , Valor Predictivo de las Pruebas , Valores de Referencia , Estudios Retrospectivos , Factores Sexuales , Volumen Sistólico , Vasodilatadores , Adulto Joven
20.
Radiat Oncol ; 9: 83, 2014 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-24661323

RESUMEN

BACKGROUND: To evaluate toxicity and outcome of intensity modulated radiotherapy (IMRT) with simultaneous integrated boost (SIB) to the positive lymph nodes in patients with loco-regional advanced cervical cancer (LRACC). METHODS: The study population comprised ten patients with 18FDG-PET\CT positive lymph nodes (LNs), who underwent chemoradiation with IMRT and SIB. A dose of 50.4 Gy, in daily fractions of 1.8 Gy, was delivered to primary tumor and draining LNs. Primary tumor received an additional external beam boost to a total dose of 55.8 Gy. A SIB of 62 Gy, in daily fractions of 2 Gy, was delivered to the 18FDG-PET\CT positive LNs. Finally, a high dose rate brachytherapy (HDRB) boost (15 - 18 Gy) was administered to the primary tumor. The primary goal of this study was to evaluate acute and early late toxicity and loco-regional control. RESULTS: The median number of irradiated LNs per patient was 3 (range: 1-6) with a median middle nodal SIB-volume of 26.10 cm3 (range, 11.9-82.50 cm3). Median follow-up was 20 months (range, 12 to 30 months). Acute and late grade 3 toxicity was observed in 1 patient. Three of the patients developed a recurrence, one in the form of a local tumor relapse, one had a paraaortic LN metastasis outside the treated volume and the last one developed a distant metastasis. CONCLUSION: IMRT with SIB in the region of 18FDG-PET positive lymph nodes appears to be an effective therapy with acceptable toxicity and might be useful in the treatment of patients with locally advanced cervical cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Braquiterapia , Carcinoma de Células Escamosas/radioterapia , Fluorodesoxiglucosa F18 , Ganglios Linfáticos/efectos de la radiación , Recurrencia Local de Neoplasia/radioterapia , Radioterapia de Intensidad Modulada , Neoplasias del Cuello Uterino/radioterapia , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Quimioradioterapia , Femenino , Estudios de Seguimiento , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Tomografía de Emisión de Positrones , Pronóstico , Radiofármacos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Tasa de Supervivencia , Tomografía Computarizada por Rayos X , Neoplasias del Cuello Uterino/mortalidad , Neoplasias del Cuello Uterino/patología
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