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1.
Acad Radiol ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38016824

RESUMO

RATIONALE AND OBJECTIVES: Hepatocellular carcinoma (HCC) treatment often requires transarterial chemoembolization (TACE). However, TACE efficacy is controversial in the presence of portal vein thrombosis (PVT). Although transarterial radioembolization (TARE) benefit was previously documented in PVT, neither the objective tumor response (OTR) after TARE with Iodine-131-lipiodol (131I-lipiodol) nor the PVT effect on the results of locoregional therapies was accurately measured in prospective clinical trials. The aim of this study was to compare OTR and survival obtained by TARE with 131I-lipiodol versus TACE in patients with cirrhosis and HCC, as well as between those with and without PVT. MATERIALS AND METHODS: 33 patients were included, from whom 38 tumors were assessed. OTR was quantified by a special algorithm to measure hypervascular HCC tissue. RESULTS: 19 tumors received each therapy. Nine subjects (27%) had PVT, most of them in the TARE group (p = 0.026). Mean OTR according to the tumor volumes was 24.2% ± 56% after TARE and 32.8% ± 48.9% after TACE, with no difference between the treatments (p = 0.616). Similar values were also observed between those with and without PVT (p = 0.704). Mean survival was 340 days and did not differ between the two treatments (p = 0.596), but was 194 days in PVT cases (p = 0.007). CONCLUSIONS: This is the first study in which OTR obtained by TARE with 131I-lipiodol is accurately measured. Additionally, PVT impact on survival after TARE and TACE was precisely documented. Although the TARE group had more PVT subjects (who had shorter survival), TARE and TACE achieved similar OTR and OS rates.

2.
Artigo em Inglês | MEDLINE | ID: mdl-36704649

RESUMO

Background: Hepatic epithelioid hemangioendothelioma (HEHE) is a rare neoplastic disease of varied presentation and unspecific radiological signs in the early stages. The diagnostic delay can lead to metastatic disease, thus increasing the tumor burden and reducing the treatment options. HEHE is usually deemed a slow-growing tumor, but its speed of growth is poorly reported and still unknown. Case Description: In this case report, we documented a HEHE diagnosed in a young woman who had complaints of abdominal pain, weight loss and bloating for a long time. The typical findings observed in histological studies were not promptly recognized in the histological analyzes, even after two laparoscopic-guided liver biopsies, delaying the diagnosis until extrahepatic tumor spreading. Findings observed in computed tomography, magnetic resonance imaging and histological studies are presented. The coalescence of nodules and the rising of giant masses, occupying large parts of the liver in a specific time span, were registered and quantified. As opposed to prior reports, the results show that hepatic HEHE can grow rapidly, reinforcing the need of early diagnosis, thus avoiding the complications presented herein. Conclusions: The findings observed via radiological and histological imaging that could have avoided the diagnosis delay are depicted and discussed, showing that HEHE can rise faster than previously documented.

4.
Neuroimage Clin ; 19: 302-310, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30013913

RESUMO

Branched-chain amino acids increase the brain perfusion of patients with hepatic encephalopathy (HE), but the amino acid and the mechanisms involved are still unknown. This study compared brain perfusion and clinical improvement during leucine or isoleucine supplementation. After randomization, 27 subjects with cirrhosis and HE received leucine or isoleucine supplements for one year. Brain single Photon Emission Computed Tomography (SPECT) and dynamic brain scintigraphy (DBS) were performed pretreatment and at 1, 8 and 12 months of supplementation. Brain perfusion was increased only in the isoleucine group at 8 months of treatment by both SPECT and DBS (p < 0.001 and p = 0.05, respectively) and by SPECT at the 12th month (p < 0.05). This was associated with hepatic encephalopathy improvement at 8 and 12 months (p = 0.008 and 0.004, respectively), which was not observed in the leucine group (p = 0.313 and 0.055, respectively). Isoleucine supplementation achieved a better impact on brain perfusion restoration in HE.


Assuntos
Encéfalo/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Encefalopatia Hepática/diagnóstico por imagem , Isoleucina/farmacologia , Leucina/farmacologia , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Circulação Cerebrovascular/fisiologia , Método Duplo-Cego , Feminino , Encefalopatia Hepática/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
5.
Quant Imaging Med Surg ; 7(3): 318-325, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28811998

RESUMO

BACKGROUND: The purpose of the present study was to evaluate differences in lung damage in patients with paracoccidioidomycosis (PCM) in two endemic regions of Brazil (Botucatu, SP, in the southeastern region and Campo Grande, MS, in the west central region). METHODS: The study sought to objectively quantify fibrosis and emphysema treated patients using high-resolution computed tomography (HRCT) that was performed according to an established and validated computational method. The analysis was based on clinical data that were associated with objective quantifications of pulmonary sequelae. We performed a retrospective analysis of HRCT exams from 32 successfully treated patients with the chronic form of PCM. The two groups had similar characteristics with regard to age, symptom duration, smoking history, and titers on a diagnostic serologic test. RESULTS: The statistical analysis revealed more severe cases and a higher percentage of emphysema in the Campo Grande group. The mean percentages of emphysema were 40.2% and 13.6% in the Campo Grande and Botucatu groups, respectively. The percentage of fibrosis was significantly higher in the Botucatu group (11.3%) than in the Campo Grande group (2.3%). CONCLUSIONS: The present results may reflect differences in cryptic species of P. brasiliensis in these two geographic regions of Brazil. Further studies should be done to clarify the differences observed herein. Such findings may help unveil differences among cryptic species in terms of the pulmonary consequences that are caused by this disease, which would be highly beneficial to PCM patients.

6.
Phys Med ; 37: 58-67, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28535916

RESUMO

PURPOSE: The aim of the present study was to determine the efficiency of six methods for calculate the effective dose (E) that is received by health professionals during vascular interventional procedures. METHODS: We evaluated the efficiency of six methods that are currently used to estimate professionals' E, based on national and international recommendations for interventional radiology. Equivalent doses on the head, neck, chest, abdomen, feet, and hands of seven professionals were monitored during 50 vascular interventional radiology procedures. Professionals' E was calculated for each procedure according to six methods that are commonly employed internationally. To determine the best method, a more efficient E calculation method was used to determine the reference value (reference E) for comparison. RESULTS: The highest equivalent dose were found for the hands (0.34±0.93mSv). The two methods that are described by Brazilian regulations overestimated E by approximately 100% and 200%. The more efficient method was the one that is recommended by the United States National Council on Radiological Protection and Measurements (NCRP). The mean and median differences of this method relative to reference E were close to 0%, and its standard deviation was the lowest among the six methods. CONCLUSIONS: The present study showed that the most precise method was the one that is recommended by the NCRP, which uses two dosimeters (one over and one under protective aprons). The use of methods that employ at least two dosimeters are more efficient and provide better information regarding estimates of E and doses for shielded and unshielded regions.


Assuntos
Exposição Ocupacional , Doses de Radiação , Monitoramento de Radiação/métodos , Radiologia Intervencionista , Pessoal de Saúde , Humanos , Proteção Radiológica
7.
Medicine (Baltimore) ; 93(25): e167, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25437031

RESUMO

This study presents methodology for objectively quantifying the pulmonary region affected by emphysemic and fibrotic sequelae in treated patients with paracoccidioidomycosis. This methodology may also be applied to any other disease that results in these sequelae in the lungs.Pulmonary high-resolution computed tomography examinations of 30 treated paracoccidioidomycosis patients were used in the study. The distribution of voxel attenuation coefficients was analyzed to determine the percentage of lung volume that consisted of emphysemic, fibrotic, and normal tissue. Algorithm outputs were compared with subjective evaluations by radiologists using a scale that is currently used for clinical diagnosis.Affected regions in the patient images were determined by computational analysis and compared with estimates by radiologists, revealing mean (± standard deviation) differences in the scores for fibrotic and emphysemic regions of 0.1% ±â€Š1.2% and -0.2% ±â€Š1.0%, respectively.The computational results showed a strong correlation with the radiologist estimates, but the computation results were more reproducible, objective, and reliable.


Assuntos
Pneumopatias Fúngicas/fisiopatologia , Pulmão/diagnóstico por imagem , Paracoccidioidomicose/fisiopatologia , Algoritmos , Diagnóstico por Computador , Enfisema/diagnóstico por imagem , Fibrose/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X
8.
Radiat Oncol ; 9: 166, 2014 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-25064234

RESUMO

BACKGROUND: Hepatocellular carcinoma is a primary tumor of the liver and involves different treatment modalities according to the tumor stage. After local therapies, the tumor evaluation is based on the mRECIST criteria, which involves the measurement of the maximum diameter of the viable lesion. This paper describes a computed methodology to measure through the contrasted area of the lesions the maximum diameter of the tumor by a computational algorithm. METHODS: 63 computed tomography (CT) slices from 23 patients were assessed. Non-contrasted liver and HCC typical nodules were evaluated, and a virtual phantom was developed for this purpose. Optimization of the algorithm detection and quantification was made using the virtual phantom. After that, we compared the algorithm findings of maximum diameter of the target lesions against radiologist measures. RESULTS: Computed results of the maximum diameter are in good agreement with the results obtained by radiologist evaluation, indicating that the algorithm was able to detect properly the tumor limits. A comparison of the estimated maximum diameter by radiologist versus the algorithm revealed differences on the order of 0.25 cm for large-sized tumors (diameter > 5 cm), whereas agreement lesser than 1.0 cm was found for small-sized tumors. CONCLUSIONS: Differences between algorithm and radiologist measures were accurate for small-sized tumors with a trend to a small decrease for tumors greater than 5 cm. Therefore, traditional methods for measuring lesion diameter should be complemented non-subjective measurement methods, which would allow a more correct evaluation of the contrast-enhanced areas of HCC according to the mRECIST criteria.


Assuntos
Algoritmos , Carcinoma Hepatocelular/diagnóstico por imagem , Quimioembolização Terapêutica , Meios de Contraste , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Imagens de Fantasmas , Prognóstico
9.
Drug Dev Ind Pharm ; 40(8): 1123-31, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23815300

RESUMO

CONTEXT: Alternating Current Biosusceptometry is a magnetically method used to characterize drug delivery systems. This work presents a system composed by an automated ACB sensor to acquire magnetic images of floating tablets. OBJECTIVE: The purpose of this study was to use an automated Alternating Current Biosusceptometry (ACB) to characterize magnetic floating tablets for controlled drug delivery. MATERIALS AND METHODS: Floating tablets were prepared with hydroxypropyl methylcellulose (HPMC) as hydrophilic gel material, sodium bicarbonate as gas-generating agent and ferrite as magnetic marker. ACB was used to characterize the floating lag time and the tablet hydration rate, by quantification of the magnetic images to magnetic area. Besides the buoyancy, the floating tablets were evaluated for weight uniformity, hardness, swelling and in vitro drug release. RESULTS: The optimized tablets were prepared with equal amounts of HPMC and ferrite, and began to float within 4 min, maintaining the flotation during more than 24 h. The data of all physical parameters lied within the pharmacopeial limits. Drug release at 24 h was about 40%. CONCLUSIONS: The ACB results showed that this study provided a new approach for in vitro investigation of controlled-release dosage forms. Moreover, using automated ACB will also be possible to test these parameters in humans allowing to establish an in vitro.in vivo correlation (IVIVC).


Assuntos
Preparações de Ação Retardada/química , Magnetismo/métodos , Metronidazol/química , Tecnologia Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Excipientes/química , Compostos Férricos/química , Géis/química , Dureza , Humanos , Derivados da Hipromelose/química , Bicarbonato de Sódio/química , Comprimidos/química
10.
J Biol Eng ; 6(1): 6, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22587220

RESUMO

AC Biosusceptometry (ACB) was previously employed towards recording gastrointestinal motility. Our data show a reliable and successful evaluation of gastrointestinal transit of liquid and solid meals in rats, considering the methods scarcity and number of experiments needed to endorsement of drugs and medicinal plants. ACB permits real time and simultaneous experiments using the same animal, preserving the physiological conditions employing both meals with simplicity and accuracy.

11.
Med Phys ; 39(3): 1357-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22380369

RESUMO

PURPOSE: The main purpose of the present study was to determine the amounts of different tissues in the chest of the newborn patient (age ≤1 year), with the aim of developing a homogeneous phantom chest equivalent. This type of phantom is indispensable in the development of optimization procedures for radiographic techniques, including dosimetric control, which is a crucial aspect of pediatric radiology. The authors present a systematic set of procedures, including a computational algorithm, to estimate the amounts of tissues and thicknesses of the corresponding simulator material plates used to construct the phantom. METHODS: The Gaussian fit of computed tomographic (CT) analysis was applied to classify and quantify different biological tissues. The methodology is summarized with a computational algorithm, which was used to quantify tissues through automated CT analysis. The thicknesses of the equivalent homogeneous simulator material plates were determined to construct the phantom. RESULTS: A total of 180 retrospective CT examinations with anterior-posterior diameter values ranging 8.5-13.0 cm were examined. The amounts of different tissues were evaluated. The results provided elements to construct a phantom to simulate the infant chest in the posterior-anterior or anterior-posterior (PA/AP) view. CONCLUSIONS: To our knowledge, this report represents the first demonstration of an infant chest phantom dedicated to the radiology of children younger than one year. This phantom is a key element in the development of clinical charts for optimizing radiographic technique in pediatric patients. Optimization procedures for nonstandard patients were reported previously [Pina et al., Phys. Med. Biol. 49, N215-N226 (2004) and Pina et al., Appl. Radiat. Isot. 67, 61-69 (2009)]. The constructed phantom represents a starting point to obtain radiologic protocols for the infant patient.


Assuntos
Imagens de Fantasmas , Radiografia Torácica/instrumentação , Tórax/citologia , Humanos , Lactente
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