Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
1.
Ann Vasc Surg ; 94: 223-228, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36906133

RESUMO

BACKGROUND: Depending on the size and location of the tumor, carotid body tumor (CBT) resection can come with various complications, mostly intraoperative bleeding, and cranial nerve injuries. In the present study, we aim to evaluate 2 fairly new variables, tumor volume, and distance to the base of the skull (DTBOS), with operative complications of CBT resection. METHODS: Patients who underwent CBT surgery in Namazi hospital from 2015 to 2019 were studied using standard databases. Tumor characteristics and DTBOS were measured via computed tomography or Magnetic resonance imaging. Outcomes, including intraoperative bleeding and cranial nerve injuries, along with perioperative data were collected. RESULTS: A total of 42 cases of CBT were evaluated with an average age of 53.21 ± 12.8 and mostly female (85.7%). Based on Shamblin scoring, 2 (4.8%) were classified as group I, 25 (59.5%) as group II, and 15 (35.7%) as group III. The amount of bleeding significantly increased with an increase in the Shamblin scores (P = 0.031; median: I: 45 cc; II: 250 cc, III: 400 cc). Also, there was a significant positive correlation between the size of the tumor and the estimated amount of bleeding (correlation coefficient = 0.660; P < 0.001), and also a significant reverse correlation with between bleeding and DTBOS (correlation coefficient = -0.345; P = 0.025). During the follow-up of the patients, 6 (14.3%) had abnormalities in their neurological evaluation. Receiver operating characteristic curve analysis revealed the size of tumor cutoff level 32.7 cm3 (3.2 cm radius) to be most predictive of postoperative neurological complication with an area under the curve = 0.83, sensitivity = 83.3%, specificity = 80.6%, a negative predictive value = 96.7%, and positive predictive value of 41.7%, and an accuracy of 81.0%. Furthermore, based on the predictive power of the models in our study, we demonstrated that a combination model including the tumor size, DTBOS, along with the Shamblin score had the most predictive power for neurological complications. CONCLUSIONS: By evaluating CBT size and DTBOS, paired with the use of the Shamblin classification, a better, more insightful understanding of possible risks and complications of CBT resection can be obtained, leading to deserved levels of patient care.


Assuntos
Tumor do Corpo Carotídeo , Traumatismos dos Nervos Cranianos , Doenças do Sistema Nervoso , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Masculino , Tumor do Corpo Carotídeo/diagnóstico por imagem , Tumor do Corpo Carotídeo/cirurgia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Base do Crânio/patologia , Complicações Pós-Operatórias/etiologia , Traumatismos dos Nervos Cranianos/etiologia
2.
Radiat Phys Chem Oxf Engl 1993 ; 205: 110739, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36567703

RESUMO

Introduction: This study intended to assess the dose length product (DLP), effective cumulative radiation dose (E.D.), and additional cancer risk (ACR) due to a chest CT scan to detect or follow up the Covid-19 disease in four university-affiliated hospitals that used different imaging protocols. Indeed, this study aimed to examine the differences in decision-making between different imaging centers in choosing chest CT imaging protocols during the pandemic, and to assess whether a new diagnostic reference level (DRL) is needed in pandemic situations. Methods: This retrospective study assessed the E.D. of all chest imagings for Covid-19 for six months in four different hospitals in our country. Imaging parameters and DLP (mGy.cm) were recorded. The E.D.s and ACRs from chest CT scans were calculated using an online calculator. Results: Thousand-six hundred patients were included in the study. The mean cumulative dose due to chest CT was 3.97 mSv which might cause 2.59 × 10-2 ACR. The mean cumulative E.D. in different hospitals was in the range of 1.96-9.51 mSv. Conclusions: The variety of mean E.D.s shows that different hospitals used different imaging protocols. Since there is no defined DRL in the pandemic, some centers use routine protocols, and others try to reduce the dose but insufficiently.In pandemics such as Covid-19, when CT scan is used for screening or follow-up, DLPs can be significantly lower than in normal situations. Therefore, international regularized organizations such as the international atomic energy agency (IAEA) or the international commission on radiological protection (IRCP) should provide new DRL ranges.

3.
J Med Ultrasound ; 31(2): 107-111, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576420

RESUMO

Background: The objective of this study was to determine the adherence of radiologists to the guideline of the Society of Radiologists in Ultrasound (SRU)-2010 for the follow-up of ovarian cysts in patients during 2015-2016. Methods: The patients' data, referring for transvaginal and pelvic ultrasonography, suffering from ovarian cyst were assessed in terms of menopause status, cyst size, and type, as well as follow-ups recommended by radiologist to assess the adherence of reports to SRU-2010. Results: Three hundred and sixty-four sonography reports were investigated. Seventy-seven percent of the reports had adhered to SRU-2010, 9.9% and 9.1% had under/overmanagement, and 4.1% was incomplete. 94.2% and 5.8% of cases were in pre/postmenopause status, respectively. The highest adherence belonged to cysts in size <1 cm, 1-3 cm, 5-7 cm. The highest adherence, over/undermanagement, and incomplete reports belonged to corpus luteum, hemorrhagic, dermoid cysts, and nodules without flow. The adherence of sonography reports to SRU-2010 for accidental ovarian cysts was 76.9%. Conclusion: The tendency for overmanagement of simple cysts in premenopausal women and the tendency for undermanagement in simple cysts and in postmenopausal women were higher, respectively. It is expected that more training of the guideline to radiologists will lead to the reduction of unnecessary follow-up, which in turn leads to reduced patient's anxiety and cost of treatment.

4.
Pol J Radiol ; 85: e353-e360, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817768

RESUMO

PURPOSE: Although mammography is a gold standard for breast cancer screening, the number of cancers that cannot be detected with mammography is substantial, especially in dense-breast (DB) women. Breast sonography can be a useful and powerful screening tool in these cases. The aim of this study is to assess the application of whole-breast sonography in the evaluation of breast lesions in women with DB tissue and estimate its accuracy in comparison with mammography. MATERIAL AND METHODS: A total of 207 asymptomatic DB women participated in this study. The breast tissue density was assessed using ACR BI-RADS. Patients underwent high-resolution ultrasonography of the breast in addition to physical examination and mammography. Different risk factors were also assessed. RESULTS: 152 of 207 (73.4%) cases who had mammography performed had DB, and 55 (26.6%) cases had very dense breasts (very DBs). None of the cases had a positive history of malignancy, while 19% of them had a positive history of breast cancer in first- or second-degree relatives. CONCLUSIONS: All findings were higher in cases with DB compared to very DBs except for fibroadenoma, which was detected more in cases with very DBs. Our study showed that the prevalence of different breast lesions had a significant relationship with the density of the breast. In our study, 48.3% of the cases were diagnosed with a lesion in their sonography result, although 81.0% of them were benign lesions, and the other 19.0% needed follow-up or biopsy evaluation. A substantial number of mammographically occult breast lesions, either benign or malignant, could be detected by ultrasound in DB tissue.

6.
Radiol Case Rep ; 17(10): 3767-3769, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35965940

RESUMO

Aqueductal stenosis can be a silent disease that can present in a patient for years without any signs and symptoms. This silence can occur due to CSF flow dynamics compensation, and it can continue until the increase in CSF production so that the symptoms may appear during adolescence or even later. In this study, we report an aqueduct obstruction by web, who had no symptoms except a headache and was referred for MRI in his early thirty. The patient was referred to find the cause of his episodes of headaches. If he did not follow up on his headache, he might never know about his disorder.

7.
J Med Imaging Radiat Sci ; 53(1): 107-112, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34836832

RESUMO

INTRODUCTION: Chest CT provides valuable information regarding coronavirus disease 2019 (COVID-19) during the treatment process. The present study aimed to assess the distribution of chest CT findings in outpatient (OPD) and hospitalized corona patients. MATERIAL AND METHOD: This was a retrospective study. Archived corona patient's data on the picture archiving and communication system (PACS) was assessed in terms of demographic data and patients' lungs' radiologic features. The OPD and hospitalized patients referred to University hospitals from February 20 to the study's date were evaluated. Data were analyzed using independent chi-square and t-test. RESULTS: Five hundred and fifty nine patients, including 187 OPD and 372 hospitalized patients, were analyzed. The frequency of normal chest CT, typical, and possible corona features was 37.4%, 40.8%, and 14.3%. The normal chest CT rate was significantly higher in outpatient versus hospitalized patients (P<0.001). Consolidation and/or ground-glass opacity were seen in 61% of patients, considerably higher in hospitalized patients (P<0.001). 2% and 15% OPD and hospitalized patients had more than 25% lung involvement, respectively. The frequency of other signs such as Crazy Paving, atoll sign, subpleural band/distortion also was significantly higher in hospitalized patients (P<0.001). CONCLUSION: Most OPD patients had less than 5% lung involvement or normal chest CT. The typical features of lung involvement in COVID-19 were significantly higher in hospitalized patients.


Assuntos
COVID-19 , Humanos , Pacientes Ambulatoriais , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2 , Tomografia Computadorizada por Raios X
8.
J Med Imaging Radiat Sci ; 53(1): 102-106, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34802965

RESUMO

INTRODUCTION: Voiding cystourethrogram (VCUG) is an imaging technique for diagnosing urinary-reflux. VCUG requires X-ray exposure, increasing the risk of malignancies induced by ionizing radiation, especially in children. Considering the importance of early diagnosis of urinary-reflux using VCUG to prevent kidney complications and the significance of reducing the radiation dose during this imaging, this study intends to reduce the imaging views of VCUG and evaluate the urinary-reflux, using a reduced number of images. MATERIAL AND METHODS: Children referred to a University hospital who underwent VCUG participated in this study. The routine VCUG procedure contained five images. Two images of full-bladder and post-void of each patient were considered a simplified procedure and were evaluated by two radiologists to determine reflux and its grade. The sensitivity and specificity of simplified VCUG were determined. RESULTS: 182 patients with a mean age of 5.36±4.95 years old participated in this study. There were 90% and 82% agreement between routine and simplified VCUG results in the left and right kidneys. The simplified VCUG had 87.2% and 100% sensitivity and specificity in detecting the left-side reflux, 83 .9% and 100%, to detect the right-side reflux. CONCLUSION: The results showed that using two images instead of five can effectively diagnose and grade urinary-reflux. The simplified VCUG had a relatively good and acceptable agreement in comparison to the routine cystourethrogram. It can effectively reduce the patient's radiation dose, especially in patients who need to perform serial bladder imaging for follow-up after operation.


Assuntos
Redução da Medicação , Refluxo Vesicoureteral , Criança , Pré-Escolar , Cistografia/métodos , Humanos , Lactente , Radiografia , Bexiga Urinária/diagnóstico por imagem , Refluxo Vesicoureteral/complicações , Refluxo Vesicoureteral/diagnóstico por imagem
9.
Cureus ; 14(4): e23956, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35547407

RESUMO

BACKGROUND: The CT findings of cirrhosis caused by primary sclerosing cholangitis (PSC) differ from cryptogenic cirrhosis. PSC could become complicated with biliary cirrhosis and cholangiocarcinoma. This study aimed at augmenting the information on the role of the three-phasic-abdominopelvic CT scan in PSC. MATERIAL AND METHODS: A total of 185 CT scans were retrospectively reviewed, including 100 patients with cryptogenic cirrhosis and 85 patients with PSC-cirrhosis. Different morphologic criteria were compared, including segmental atrophy/hypertrophy, hepatic contour, portal-hypertension, perihilar lymphadenopathy, biliary tree dilatation, gallbladder appearance. Inflammatory-bowel-disease (IBD) and cholangiocarcinoma frequency, presence of perihilar lymph nodes (LNs), and their size during end-stage PSC cirrhosis are investigated. RESULTS: Six findings occur more frequently with PSC than those diagnosed with cryptogenic cirrhosis. Modified caudate/right lobe (m-CRL) ratio >0.73, moderate and severe lobulated liver contour, lateral left lobe atrophy, over distended gallbladder (GB), biliary tree dilatation and wall thickening, and LN sizes were higher in PSC patients as compared to cryptogenic cirrhosis (P < 0.005). Ascites and portosystemic collateral formations were significant in cryptogenic cirrhosis compared to PSC patients (P < 0.005). Cholangiocarcinoma frequency in PSC patients was 14.7%, and the frequency of inflammatory bowel disease (IBD) was 57.6%. Further, 22.4% of the patients were diagnosed with IBD and PSC simultaneously. The LN number and size in PSC patients were not different between those with or without cholangiocarcinoma. CONCLUSION: Using three-phasic CT scans and PSC characteristics could be considered as an additional suggestion besides pathology measures. Diagnosis of PSC based on histological findings could be a last resort due to its invasive essence and specific characteristics of PSC in imaging.

10.
J Forensic Leg Med ; 85: 102296, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34896891

RESUMO

INTRODUCTION: Dating the exact or estimated time of trauma is an important issue facing forensic medicine. Several clinical and radiological methods were used to achieve this purpose. In the recent study, we aimed to track the changes in the signal intensity of the extra-axial brain hematoma using magnetic resonance imaging (MRI) conventional sequences as well as diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC). MATERIALS AND METHODS: Considering inclusion and exclusion criteria, all patients with blunt head trauma were involved. After proper management., stabilization, and resuscitation, the participants were assessed using conventional sequences of MRI and DWI twenty-four hours, forty-eight hours, and three weeks after the injury. Temporal changes of signal intensity were compared by Wilcoxon ranged test. RESULTS: Sixteen patients sustaining blunt head trauma were included in this study. The study showed that during the time, diffusion restriction could be seen in an extraaxial hematoma. At the first 24 hours, the signal of hematoma was void in 87.5% of DWI and 100% of ADC. On the second day, they were hypo-signal in 75% of DWI and 100% 0f ADCs, and after three weeks, 100% of cases were hyper-signal in DWI and hypo-signal ADCs. CONCLUSION: This preliminary study has shown that the DWI can be used to detect and track the extra-axial hematoma. The signal intensity was void during the first twentyfour hours, although it became hypo-signal after 48 hours. Of note, the diffusion restriction is noted after three weeks.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Difusão , Imagem de Difusão por Ressonância Magnética , Hematoma/diagnóstico por imagem , Humanos
11.
Ultrasound ; 30(1): 44-51, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35173778

RESUMO

INTRODUCTION: We aimed to describe shear wave elastography parameters of non-mass lesions of the breast and to assess the measures of diagnostic accuracy of shear wave elastography in the differentiation of non-mass lesions compared with conventional ultrasound, using histopathologic results as the reference standard. METHODS: This retrospective study included breast ultrasound-detected non-mass lesions with a confirmed pathologic diagnosis during a two-year study period. B-mode ultrasound and shear wave elastography were performed for all lesions before biopsy. Ultrasound features, shear wave elastography parameters (mean elasticity and maximum stiffness color), as well as Breast Imaging-Reporting and Data System categories were recorded for each lesion. Measures of diagnostic accuracy of ultrasound and ultrasound + shear wave elastography were also assessed. RESULTS: From a total of 567 breast lesions requiring core-needle biopsy, 49 (8.6%) were considered as non-mass lesions. Based on histopathologic reports, 32 patients (65.3%) had non-high-risk benign lesions, five (10.2%) had high-risk benign lesions, five (10.2%) had ductal carcinoma in situ, and seven (14.3%) had invasive carcinoma. There was no significant difference in patients' age and palpability between benign and malignant lesions (p = 0.16 and p = 0.12, respectively). Mean elasticity values and Breast Imaging-Reporting and Data System categories were significantly higher among malignant lesions compared with benign non-mass lesions (both p < 0.001). Furthermore, the addition of shear wave elastography to grayscale ultrasound increased the specificity, positive predictive value, and diagnostic accuracy. CONCLUSION: The complementary use of shear wave elastography with conventional ultrasound might help in the differentiation of non-mass breast lesions and has the potential to decrease the frequency of unnecessary biopsies performed for benign non-mass lesions.

12.
J Med Imaging Radiat Sci ; 52(1): 121-126, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33446443

RESUMO

INTRODUCTION: One of the most common demyelinating disorders is Multiple Sclerosis (MS), which can lead to extensive disability in patients. Appearance of active lesions can be an important sign of disease development. The correlation between the restriction of DWI signal, contrast-enhancement, and demyelinated plaque's signals were evaluated in this study. MATERIAL AND METHOD: 34 MS patients with 1043 MS-plaques who had acute attacks took part in this study. Three MRI pulse-sequences, FLAIR, DWI, and post-contrast enhanced T1 weighted, were compared. Using the signal intensity of MS-lesions and normal brain tissue in FLAIR images, lesion/noise ratio (LNR) and lesion/white-matter ratio (LWR) were calculated. Sensitivity and specificity of LNR and LWR were estimated to determine a cut off value. RESULTS: 7.86% of MS-plaques were enhanced in T1 contrast-enhanced MRI. 2.4% showed DWI restriction. 0.77% showed both diffusion-restriction and T1 contrast-enhancement, 1.63% indicated diffusion-restriction but no contrast-enhancement and 7.09% showed contrast-enhancement but no diffusion-restriction. Among diffusion-restricted plaques, 32% were enhanced in T1-weighted post-contrast enhanced images and it should be noted that diffusion-restriction was seen in 9.76% of enhanced plaques. The sensitivity and specificity of the DWI restriction and its effectiveness in detecting active-plaques were calculated as 12.31% and 98.26%, respectively. The accuracy of this method in detecting the active MS-plaques estimated as 92.91%. The cut-off value for LWR and LNR was between 0.9-1 and 24-28. CONCLUSION: By calculating LNR and LWR, the FLAIR images can be evaluated to detect new MS-plaques. LWR had higher sensitivity and specificity in comparison to LNR so it is a better index in the detection of active-plaques. Although post contrast T1 is the gold standard for evaluating active plaques, in the case of a contraindication to gadolinium, DWI can offer supplemental information on the diffusion restriction of MS plaques in a non-contrast protocol.


Assuntos
Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Adolescente , Adulto , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
13.
J Med Imaging Radiat Sci ; 51(4): 654-661, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32718849

RESUMO

There are several slightly invasive methods to detect colorectal carcinoma (CRC) including colonoscopy and sigmoidoscopy; but there is no noninvasive, accurate screening test. It is recommended to initiate screening at the age of 50 for non-familial CRC. Laboratory tests are routinely suggested if internal observation and imaging are recommended for further evaluation. Spectroscopic-based imaging, such as magnetic resonance spectroscopy (MRS) is an interesting and promising tool with the potential to be an alternative to some minimally invasive procedures, such as biopsy. Accordingly, MRS might be a suitable substitution for invasive methods, such as colonoscopy. This article aimed to review the studies that have evaluated the MRS technique as a screening tool in CRC.


Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Espectroscopia de Ressonância Magnética/métodos , Colo/diagnóstico por imagem , Humanos , Reto/diagnóstico por imagem
14.
J Med Imaging Radiat Sci ; 51(1): 145-153, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31884064

RESUMO

INTRODUCTION: Owing to nonspecific clinical symptoms, Wilson disease (WD) diagnosis is often missed or delayed; hence, many patients reach end-stage liver disease. When cirrhosis takes place, it is difficult to distinguish between WD and other causes of cirrhosis by imaging alone. This study outlines abdominal computed tomography (CT) imaging findings that occur more frequently in patients with WD cirrhosis. MATERIAL AND METHODS: Fifty-seven patients with WD who had referred for liver transplantation took part in this study and underwent dynamic liver CT examination before transplantation. Qualitative and quantitative parameters including liver density, contour irregularity, dysmorphia, hypertrophy of caudate lobe, presence of focal parenchymal lesion, thickness of perihepatic fat layer, periportal thickness, lymphadenopathy, and other associated findings were recorded and evaluated. RESULTS: Among these patients, 85.9% had contour irregularity, 28% had hepatic dysmorphia, and periportal thickening and cholelithiasis were found in 25.5% and 12.3% of patients, respectively. Splenomegaly, lymphadenopathy, and portosystemic shunting were observed in all patients. Also, hyperdense nodules (>20 mm) and honeycomb pattern were detected in 65.2% and 15.2% of patients, respectively, in the arterial phase. In the portal phase, these findings were detected only in 13% and 4.3% of patients. Hypertrophy of caudate lobe was seen only in 12.2% of patients. CONCLUSION: WD-associated cirrhosis has many CT imaging findings, although most of them are nonspecific. Some findings, such as hyperdense nodules and honeycomb pattern in non-contrast-enhanced CT scan and arterial phase of triphasic CT scan with lack of hypertrophy of caudate lobes, are hallmarks of WD.


Assuntos
Degeneração Hepatolenticular/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Criança , Meios de Contraste , Feminino , Degeneração Hepatolenticular/cirurgia , Humanos , Iohexol , Cirrose Hepática/diagnóstico por imagem , Transplante de Fígado , Masculino , Ácidos Tri-Iodobenzoicos
15.
Br J Radiol ; 92(1104): 20190216, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31556332

RESUMO

OBJECTIVE: Magnetic resonance spectroscopy (MRS) has been useful in radiotherapy treatment planning (RTP) especially in tumor delineation. Routinely, 2D/3D MRSI data are used for this application. However, not all centers have access to 2D/3D MRSI. The objective of this study was to introduce a method of using single-voxel spectroscopy (SVS) data in target delineation and assess its reliability. METHODS: A gel-based phantom containing Creatine (Cr), N-acetyl-l-aspartic-acid (NAA), and Choline (Cho) was designed and built. The metabolite ratios simulate the normal and tumoral part of the brain. The jMRUI software (v. 6.0) was used to simulate a 1.5 T GE MRI scanner. The metabolite spectra provided by different time of echos (TE)s of the Point-RESolved Spectroscopy pulse-sequence (PRESS), different data-points, and post-processings were quantized by jMRUI. PseudoMRSI maps of Cho/Cr, NAA/Cr, and Cho + Cr/NAA were created. A conformity index (CI) was used to determine which metabolite-ratio isolines are more appropriate for tumor delineation. RESULTS: The simulation accuracy was verified. There were no differences > 4% between the measured and simulated spectra in peak regions. The pseudoMRSI map of Cho + Cr/NAA smoothly followed the complicated geometry of the tumor inside the gel-based phantom. The results showed that the single-voxel spectra produced by the PRESS pulse sequence with the TE of 144 ms, 512 data-points, and minimum post-processings of water suppression, eddy current correction, and baseline correction can be used for target delineation. CONCLUSION: This study suggests that SVS data can be used to aid target delineation by using a mathematical approach. This can enable a wider use of MR-derived information in radiotherapy. ADVANCES IN KNOWLEDGE: To the best of our knowledge, until now, 2D or 3D MRSI data provided from 3T MRI scanners have been used for MRS-based radiotherapy treatment planning. However, there are a lot of centers that are equipped to 1.5 T MRI scanners and some of them just equipped to SVS. This study introduces a mathematical approach to help these centers to take the benefits of MRS-based treatment planning.


Assuntos
Química Encefálica , Neoplasias Encefálicas/química , Neoplasias Encefálicas/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Imagens de Fantasmas , Ácido Aspártico/análogos & derivados , Colina , Creatina , Humanos , Reprodutibilidade dos Testes , Software
16.
Indian J Nucl Med ; 33(1): 10-13, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29430108

RESUMO

PURPOSE: Despite therapeutic effects of radioiodine in patients with differentiated thyroid cancer, there are some disadvantages due to harmful radiation to other tissues. According to the current guidelines, patients are recommended to drink lots of water and frequent voiding to reduce the amount of 131I in the body. This study was designed to assess the impact of the amount of liquid intake on reduction of the measured dose rate of radioiodine-treated patients. MATERIALS AND METHODS: A total of 42 patients with differentiated thyroid cancer without metastasis who had undergone total thyroidectomy and had been treated with radioiodine were selected. The patients were divided into two groups according to the amount of their fluid intake which was measured during the first 48 h after 131I administration. In all patients, the dose rate was measured immediately and 48 h after iodine administration. RESULTS: Each group included 21 patients. Dose rate ratio (the ratio of the second dose rate to the first dose rate) and dose rate difference ratio (the ratio of the difference between the two measured dose rates to the first dose rate) were calculated for each patient. Despite the significant difference in the amount of the liquid drunk, no statistically significant difference was seen between the different groups in parameters of dose-rate ratio and dose-rate difference ratio. CONCLUSION: Higher fluid intake (>60 ml/h in our study) alone would not effectively reduce the patient's radiation dose rate at least not more than a well-hydrated state. It seems that other interfering factors in the thyroidectomized patients may also have some impacts on this physiologic process.

18.
Technol Health Care ; 25(1): 29-35, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27447407

RESUMO

INTRODUCTION: Dose evaluation with two Monte Carlo codes using patient specific voxel phantom is presented in this paper. We employ both MCNPX and DOSXYZnrc to perform dosimetry for mathematical voxel phantoms generated by our in-house developed voxel phantom generator and EGSnrc/CTCreate respectively. MATERIAL AND METHOD: Our case study was a 2.5 × 2.4 × 2.4 cm3 tumor in the middle lobe of right lung of a male patient exposed to 6MV parallel beam. In order to compare these Monte Carlo codes with together gross tumor volume (GTV) and organ at risks (OAR) doses and dose volume histograms (DVH) were calculated. RESULTS: Comparing the mean absorbed dose results (in Gy) from both codes indicates that gross tumor volume, heart and spinal cord have 2% to 10% difference. The 10% difference between the codes were from the spinal cord region where was not in the therapy beam and it just received the scatter radiation. The dose volume DVH obtained from DOSXYZnrc results demonstrate a milder slope compared with MCNPX DVHs. CONCLUSION: It was revealed that MCNPX has some advantages in comparison to DOSXYZnrc, but it is important to consider that for equal precision in voxel dosimetry calculation, DOSXYZnrc runs faster than MCNPX and it is a great advantage.


Assuntos
Neoplasias Pulmonares/radioterapia , Método de Monte Carlo , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Masculino , Carga Tumoral
19.
Ultrasound ; 25(2): 92-97, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28567103

RESUMO

BACKGROUND: Breast pain is one of the most common complaints of women attending a gynecology clinic and general practitioners. This pain can cause anxiety and, consequently, reduce the woman's quality of life. The objective of this study was to assess the severity of pain and anxiety in patients with breast pain and normal examination, before and after breast sonography. MATERIALS AND METHODS: Among the patients with breast pain and normal examination who came for breast sonography in three centers in Shiraz during 2011-2012, 51 patients agreed to cooperate in this project. These patients filled out the questionnaire for evaluation of pain and anxiety before and after breast sonography. RESULTS: Sonography findings indicated that 88% of patients have normal sonography without any finding. The average amounts of pain severity before and after sonography were 3.3 and 2.4, respectively (p < 0.005). The average amounts of anxiety severity in patients before and after sonography were 51.9 and 37.9, respectively (p < 0.005). CONCLUSION: This study shows the severity of pain and anxiety after ultrasonography decreased significantly. It can be concluded that ultrasound findings, which reassure the patients that they do not have specific pathology, can reduce the pain and anxiety by its impact on psychological status of the patient.

20.
Health Phys ; 112(5): 494-497, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28350707

RESUMO

Increased demand for interventional radiology techniques has interventionists performing a large number of these procedures. Measurements and calculations have shown that the radiation doses received by these specialists can exceed the threshold of radiation-induced deterministic effects unless radiation protection procedures and devices are used. Proper usage of radiation protection devices can protect them from radiation-induced effects, even with a high workload. Occupational radiation protection entails proper training of interventionists to increase their awareness about available appropriate protection tools and equipment, and devices that can be used to minimize exposure, such as needle holders, tubing extensions, and injectors. This study introduces a device that can be used to fix the catheter to prevent the physician from holding the catheter by hand. The authors, also, discuss the importance of radiation protection training along with the training on new medical equipment, which can be applied to reduce the radiation dose.


Assuntos
Catéteres , Exposição Ocupacional/prevenção & controle , Exposição à Radiação/prevenção & controle , Proteção Radiológica/instrumentação , Radiografia Intervencionista/instrumentação , Fita Cirúrgica , Desenho de Equipamento , Análise de Falha de Equipamento , Exposição Ocupacional/análise , Exposição à Radiação/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA