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1.
Radiography (Lond) ; 30(2): 628-633, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330895

RESUMO

INTRODUCTION: Computed tomography (CT) imaging has become indispensable in the management of medical oncology patients. Risks associated with high cumulative effective dose (CED) are relevant in testicular cancer patients. Split-bolus protocols, whereby the contrast medium injection is divided into two, followed by combining the required phase images in a single scan acquisition has been shown to provide images of comparable image quality and less radiation dose compared to single-bolus split-phase CT for various indications. We retrospectively evaluated the performance of split-bolus and single-bolus protocols in patients having follow-up CT imaging for testicular cancer surveillance. METHODS: 45 patients with testicular cancer undergoing surveillance CT imaging of the thorax, abdomen, and pelvis who underwent split-bolus and single-bolus protocols were included. Quantitative image quality analysis was conducted by placing region of interests in pre-defined anatomical sub-structures within the abdominal cavity. The signal-to-noise ratio (SNR) and radiation dose in the form of dose length product (DLP) and effective dose (ED) were recorded. RESULTS: The DLP and ED for the single-bolus, split-phase acquisition was 506 ± 89 mGy cm and 7.59 ± 1.3 mSv, respectively. For the split-bolus, single-phase acquisition, 397 ± 94 mGy∗cm and 5.95 ± 1.4 mSv, respectively (p < 0.000). This represented a 21.5 % reduction in radiation dose exposure. The SNR for liver, muscle and fat for the single-bolus were 7.4, 4.7 and 8, respectively, compared to 5.5, 3.8 and 7.4 in the split-bolus protocol (p < 0.001). CONCLUSION: In a testicular cancer patient cohort undergoing surveillance CT imaging, utilization of a split-bolus single-phase acquisition CT protocol enabled a significant reduction in radiation dose whilst maintaining subjective diagnostic acceptability. IMPLICATIONS FOR PRACTICE: Use of split-bolus, single-phase acquisition has the potential to reduce CED in surveillance of testicular cancer patients.


Assuntos
Neoplasias Embrionárias de Células Germinativas , Neoplasias Testiculares , Masculino , Humanos , Estudos Retrospectivos , Neoplasias Testiculares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Meios de Contraste
2.
Radiography (Lond) ; 29(4): 712-720, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37196480

RESUMO

BACKGROUND: Cross-sectional study to assess the body composition of patients with Crohn's disease (CD) on standard (SDCT) and low dose CT (LDCT) protocols for the abdomen and pelvis (CTAP). We aimed to assess if a low dose CT protocol reconstructed with model-based iterative reconstruction (IR) could evaluate body morphometric data comparable to standard dose examination. METHODS: The CTAP images of 49 patients who underwent a low dose CT scan (20% of standard dose) and a second at standard dose minus 20% were assessed retrospectively. Images were collected from the PACS system, deidentified and analysed using a web-based semi-automated threshold-based segmentation tool (CoreSlicer), capable of identifying tissue type based on differences in attenuation co-efficient. The cross-sectional area (CSA) and Hounsfield units (HU) of each tissue was recorded. RESULTS: Muscle and fat CSA is well preserved on comparing these derived metrics from low dose and standard dose CT scans of abdomen and pelvic in CD ((LDCT:SDCT mean CSA (cm2); Psoas muscle - 29.00:28.67, total lumbar muscle - 127.45:125.55, visceral fat- 110.44:114.16, subcutaneous fat - 250.88:255.05)). A fixed difference exists when assessing the attenuation of muscle, with higher attenuation on the low dose protocol (LDCT:SDCT mean attenuation (HU); Psoas muscle - 61.67:52.25, total lumbar muscle - 49.29:41.20). CONCLUSION: We found comparable CSA across all tissues (muscle and fat) on both protocols with a strong positive correlation. A marginally lower muscle attenuation suggestive of less dense muscle was highlighted on SDCT. This study augments previous studies suggesting that comparable and reliable morphomic data may be generated from low dose and standard dose CT images. IMPLICATIONS FOR PRACTICE: Threshold-based segmental tools can be used to quantify body morphomics on standard and low dose computed tomogram protocols.


Assuntos
Doença de Crohn , Humanos , Doses de Radiação , Doença de Crohn/diagnóstico por imagem , Estudos Retrospectivos , Estudos Transversais , Tomografia Computadorizada por Raios X/métodos
3.
Clin Radiol ; 76(5): 393.e9-393.e17, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33468311

RESUMO

AIM: To assess the utility of a volumetric low-dose computed tomography (CT) thorax (LDCTT) protocol at a dose equivalent to a posteroanterior (PA) and lateral chest radiograph for surveillance of cystic fibrosis (CF) patients. MATERIALS AND METHODS: A prospective study was undertaken of 19 adult patients with CF that proceeded to LDCTT at 12 and 24 months following initiation of ivacaftor. A previously validated seven-section, low-dose axial CT protocol was used for the 12-month study. A volumetric LDCTT protocol was developed for the 24-month study and reconstructed with hybrid iterative reconstruction (LD-ASIR) and pure iterative reconstruction (model-based IR [LD-MBIR]). Radiation dose was recorded for each scan. Image quality was assessed quantitatively and qualitatively, and disease severity was assessed using a modified Bhalla score. Statistical analysis was performed and p-values of <0.05 were considered statistically significant. RESULTS: Volumetric LD-MBIR studies were acquired at a lower radiation dose than the seven-section studies (0.08 ± 0.01 versus 0.10 ± 0.02 mSv; p=0.02). LD-MBIR and seven-section ASIR images had significantly lower levels of image noise compared with LD-ASIR images (p<0.0001). Diagnostic acceptability scores and depiction of bronchovascular structures were found to be acceptable for axial and coronal LD-MBIR images. LD-MBIR images were superior to LD-ASIR images for all qualitative parameters assessed (p<0.0001). No significant change was observed in mean Bhalla score between 1-year and 2-year studies (p=0.84). CONCLUSIONS: The use of a volumetric LDCTT protocol (reconstructed with pure IR) enabled acquisition of diagnostic quality CT images, which were considered extremely useful for surveillance of CF patients, at a dose equivalent to a PA and lateral chest radiograph.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/uso terapêutico , Fibrose Cística/diagnóstico por imagem , Fibrose Cística/tratamento farmacológico , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Estudos Prospectivos , Doses de Radiação , Adulto Jovem
4.
Radiography (Lond) ; 27(1): 67-74, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32693990

RESUMO

INTRODUCTION: This study investigates instances of elevated radiation dose on a radiation tracking system to determine their aetiologies. It aimed to investigate the impact of radiographer feedback on these alerts. METHODS: Over two six-month periods 11,298 CT examinations were assessed using DoseWatch. Red alerts (dose length products twice the median) were identified and two independent reviewers established whether alerts were true (unjustifiable) or false (justifiable). During the second time period radiographers used a feedback tool to state the cause of the alert. A Chi-Square test was used to assess whether red alert incidence decreased following the implementation of radiographer feedback. RESULTS: There were 206 and 357 alerts during the first and second time periods, respectively. These occurred commonly with CT pulmonary angiography, brain, and body examinations. Procedural documentation errors and patient size accounted for 57% and 43% of false alerts, respectively. Radiographer feedback was provided for 17% of studies; this was not associated with a significant change in the number of alerts, but the number of true alerts declined (from 7 to 3) (χ2 = 4.14; p = 0.04). CONCLUSION: Procedural documentation errors as well as patient-related factors are associated with false alerts in DoseWatch. Implementation of a radiographer feedback tool reduced true alerts. IMPLICATIONS FOR PRACTICE: The implementation of a radiographer feedback tool reduced the rate of true dose alerts. Low uptake with dose alert systems is an issue; the workflow needs to be considered to address this.


Assuntos
Sistemas de Registro de Ordens Médicas , Documentação , Retroalimentação , Humanos , Doses de Radiação , Tomografia Computadorizada por Raios X
5.
Radiography (Lond) ; 26 Suppl 2: S62-S68, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32682731

RESUMO

Increasing integration of computed tomography (CT) into routine patient care has escalated concerns regarding associated radiation exposure. Specific patient cohorts, particularly those with cystic fibrosis (CF) and Crohn's disease, have repeat exposures and thus have an increased risk of high lifetime cumulative effective dose exposures. Thoracic CT is the gold standard imaging method in the diagnosis, assessment and management of pulmonary disease. In the setting of CF, CT demonstrates increased sensitivity compared with pulmonary function tests and chest radiography. Furthermore, in specific cases of Crohn's disease, CT demonstrates diagnostic superiority over magnetic resonance imaging (MRI) for radiological evaluation. Low dose CT protocols have proven beneficial in the evaluation of CF, Crohn's disease and renal calculi, and in the follow up of testicular cancer patients. For individuals with chronic conditions warranting frequent radiological follow up, the focus must continue to be the incorporation of appropriate CT use into patient care. This is of particular importance for the paediatric population who are most susceptible to potential radiation induced malignancy. CT technological developments continue to focus on radiation dose optimisation. This article aims to highlight these advancements, which prioritise the acquisition of diagnostically satisfactory images with the least amount of radiation possible.


Assuntos
Fibrose Cística , Neoplasias Testiculares , Criança , Redução da Medicação , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia Computadorizada por Raios X
6.
Radiography (Lond) ; 24(4): 334-339, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30292502

RESUMO

INTRODUCTION: Optimization of image quality and patient radiation dose is achieved in part by positioning the patient at the isocenter of the CT gantry. The aim of this study was to establish whether there was increased isocenter misalignment (IM) in CT colonography (CTC) scans by comparing patient position during the prone part of a CTC to patient position during renal stone protocol CT (CT-KUB) and patient position during the supine part of a CTC to patient position during abdominopelvic CT (CT-AP). METHODS: Two hundred and twenty two consecutive outpatient adult CTC studies performed between January and December 2016 were retrospectively analyzed. Automated dose-tracking software was used to quantify IM in the x and y planes. Renal stone CT-KUB (n = 100) and standard CT-AP (n = 100) were used as comparison studies. RESULTS: IM during CTC was significantly greater in the y-axis compared with the x-axis for both prone (p = 0.002) and supine (p < 0.001) scanning. IM was significantly greater during prone CTC compared with CT-KUB (p = 0.008) and during supine CTC compared with CT-AP (p = 0.0001). IM was shown to be slightly greater in studies performed by more experienced radiographers (p = 0.04). IM was not associated with patient age, gender or size (p > 0.05 for all). CONCLUSION: Isocenter misalignment is greater during CT colonography compared with CT-KUB or CT-AP. Strategies for improving patient positioning could include radiographer education and automated patient centering solutions.


Assuntos
Colonografia Tomográfica Computadorizada/métodos , Posicionamento do Paciente/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Colo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
7.
Radiography (Lond) ; 24(4): 345-351, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30292504

RESUMO

INTRODUCTION: The aim of this study was to assess and compare the effects of CT image reconstruction techniques on low-dose CT image quality using phantoms. METHODS: Anthropomorphic torso and spatial/contrast-resolution phantoms were scanned at decreasing tube currents between 400 and 10 mA. CT thorax and abdomen/pelvis series were reconstructed with filtered back projection (FBP) alone, combined 40% adaptive statistical iterative reconstruction & FBP (ASIR40), and model-based iterative reconstruction (MBIR) [(resolution-preference 05 (RP05) and RP20 in the thorax and RP05 and noise-reduction 05 (NR05) in the abdomen)]. Two readers rated image quality quantitatively and qualitatively. RESULTS: In thoracic CT, objective image noise on MBIR RP05 data sets outperformed FBP at 200, 100, 50 and 10 mA and outperformed ASIR40 at 50 and 10 mA (p < 0.001). MBIR RP20 outperformed FBP at 50 and 10 mA and outperformed ASIR40 at 10 mA (p < 0.001). Compared with both FBP and ASIR40, MBIR RP05 demonstrated significantly better signal-to-noise ratio (SNR) at 10 mA. In abdomino-pelvic CT, MBIR RP05 and NR05 outperformed FBP and ASIR at all tube current levels for objective image noise. NR05 demonstrated greater SNR at 200, 100, 50 and 10 mA and RP05 demonstrated greater SNR at 50 and 10 mA compared with both FBP and ASIR. MBIR images demonstrated better subjective image quality scores. Spatial resolution, low-contrast detectability and contrast-to-noise ratio (CNR) were comparable between image reconstruction techniques. CONCLUSION: CTs reconstructed with MBIR have lower image noise and improved image quality compared with FBP and ASIR. These effects increase with reduced radiation exposure confirming optimal use for low-dose CT imaging.


Assuntos
Radiografia Abdominal/métodos , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos , Imagens de Fantasmas , Doses de Radiação , Radiografia Abdominal/instrumentação , Radiografia Torácica/instrumentação , Razão Sinal-Ruído , Tomografia Computadorizada por Raios X/instrumentação
8.
Ir Med J ; 109(1): 347-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26904794

RESUMO

Testicular pain is a common presentation in the emergency department. The cause includes a wide array of differentials. This report highlights a case of thrombosis of the pampiniform plexus as a rare cause of testicular pain. Doppler ultrasound should be the first line investigation. Symptomatic relief with anti-inflammatory medication should be sufficient for management.


Assuntos
Dor/etiologia , Testículo/irrigação sanguínea , Trombose Venosa/complicações , Humanos , Masculino , Cordão Espermático/diagnóstico por imagem , Testículo/diagnóstico por imagem , Ultrassonografia Doppler , Trombose Venosa/diagnóstico por imagem , Adulto Jovem
9.
Clin Transl Oncol ; 18(5): 533-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26307754

RESUMO

PURPOSE: Survival rates among patients with lymphoma continue to improve. Strategies aimed at reducing potential treatment-related toxicity are increasingly prioritized. While radiological procedures play an important role, ionizing radiation exposure has been linked to an increased risk of malignancy, particularly among individuals whose cumulative radiation exposure exceeds a specific threshold (75 millisieverts). METHODS: Within this retrospective study, the cumulative radiation exposure dose was quantified for 486 consecutive patients with lymphoma. RESULTS: The median estimated total cumulative effective dose (CED) of ionizing radiation per subject was 69 mSv (42-118). However, younger patients (under 40 years) had a median CED of 89 mSv (55-124). CONCLUSION: This study highlights the considerable radiation exposure occurring among patients with lymphoma as a result of diagnostic imaging. To limit the risk of secondary carcinogenesis, consideration should be given to monitoring cumulative radiation exposure in individual patients as well as considering imaging modalities, which do not impart an ionizing radiation dose.


Assuntos
Diagnóstico por Imagem/efeitos adversos , Linfoma/diagnóstico por imagem , Neoplasias Induzidas por Radiação/etiologia , Radiação Ionizante , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Linfoma/complicações , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Induzidas por Radiação/patologia , Tomografia por Emissão de Pósitrons , Prognóstico , Estudos Prospectivos , Doses de Radiação , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
10.
Lung ; 193(1): 71-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25381634

RESUMO

INTRODUCTION: Despite advances in diagnosis and management, the outcomes for both lung cancer and idiopathic pulmonary fibrosis (IPF) are still unfavourable. The pathophysiology and outcomes for patients with concomitant lung cancer and IPF remains unclear. METHODOLOGY: A retrospective analysis was performed of all patients presenting with concomitant IPF and lung cancer to our centre over a 3-year period. Patients with connective tissue disease, asbestos exposure, sarcoidosis, previous thoracic radiation, radiological evidence of fibrosis but no histological confirmation of lung cancer, or the use of medications known to cause pulmonary fibrosis were excluded. We describe clinical, radiological and pathological characteristics of this group. We also report the response to standardized lung cancer therapy in this cohort. RESULTS: Of 637 lung cancer patients, 34 were identified with concomitant IPF (5.3 %) and all were smokers. 85 % had non-small cell lung cancer, 41 % were squamous cell cancers. The majority of tumours were located in the lower lobes, peripheral and present in an area of honeycombing. Despite the fact that approximately 2/3rds of the patients had localised or locally advanced lung cancer, the outcome of therapy for lung cancer was extremely poor regardless of tumour stage or severity of IPF. CONCLUSIONS: At our centre, 1/20 patients with lung cancer have concomitant IPF. The majority of these tumours are small in size, peripheral in location and squamous cell carcinoma; in an area of honey combing. The outcome for concomitant lung cancer and IPF regardless of stage or therapy is poor.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/complicações , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma de Células Escamosas/complicações , Carcinoma de Células Escamosas/diagnóstico , Fibrose Pulmonar Idiopática/complicações , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/diagnóstico , Pulmão/diagnóstico por imagem , Pulmão/patologia , Idoso , Biópsia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Feminino , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Fibrose Pulmonar Idiopática/mortalidade , Irlanda , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fumar/efeitos adversos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Carga Tumoral
11.
Eur Radiol ; 25(4): 1005-13, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25500962

RESUMO

OBJECTIVES: Risks associated with high cumulative effective dose (CED) from radiation are greater when imaging is performed on younger patients. Testicular cancer affects young patients and has a good prognosis. Regular imaging is standard for follow-up. This study quantifies CED from diagnostic imaging in these patients. METHODS: Radiological imaging of patients aged 18-39 years, diagnosed with testicular cancer between 2001 and 2011 in two tertiary care centres was examined. Age at diagnosis, cancer type, dose-length product (DLP), imaging type, and frequency were recorded. CED was calculated from DLP using conversion factors. Statistical analysis was performed with SPSS. RESULTS: In total, 120 patients with a mean age of 30.7 ± 5.2 years at diagnosis had 1,410 radiological investigations. Median (IQR) surveillance was 4.37 years (2.0-5.5). Median (IQR) CED was 125.1 mSv (81.3-177.5). Computed tomography accounted for 65.3 % of imaging studies and 98.3 % of CED. We found that 77.5 % (93/120) of patients received high CED (>75 mSv). Surveillance time was associated with high CED (OR 2.1, CI 1.5-2.8). CONCLUSIONS: Survivors of testicular cancer frequently receive high CED from diagnostic imaging, mainly CT. Dose management software for accurate real-time monitoring of CED and low-dose CT protocols with maintained image quality should be used by specialist centres for surveillance imaging. KEY POINTS: • CT accounted for 98.3 % of CED in patients with testicular cancer. • Median CED in patients with testicular cancer was 125.1 mSv • High CED (>75 mSv) was observed in 77.5 % (93/120) of patients. • Dose tracking and development of low-dose CT protocols are recommended.


Assuntos
Diagnóstico por Imagem , Neoplasias Embrionárias de Células Germinativas/diagnóstico por imagem , Neoplasias Testiculares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Humanos , Masculino , Doses de Radiação
12.
Eur J Radiol ; 83(5): 843-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24581594

RESUMO

INTRODUCTION: The aim of this study was to identify radiological factors that may reduce false-positive results and increase diagnostic accuracy when staging the mediastinum of patients with non-small cell lung carcinoma (NSCLC). METHODS: This was a retrospective, interdisciplinary, per-node analysis study. We included patients with NSCLC and mediastinal nodes with an SUV max in the range of 2.5-4.0 on PET-CT. We hypothesized that the greatest number of false positive cases would occur in this cohort of patients. RESULTS: A total of 92 mediastinal lymph nodes were analyzed in 44 patients. Mediastinal disease (N2/N3) was histologically confirmed in 15 of 44 patients and in 34 of 92 lymph nodes; positive predictive value of 37% and false positive rate of 63%. Lymph node SUV max, tumor size, ratio of node SUV max to tumor SUV max (SUVn/SUVp), and ratio of node SUV max to node size (SUV n/SADn) were significantly higher in true positive cases. Using a threshold of 0.3 for SUV node/tumor and 3 for SUV node/size yielded sensitivities of 91% and 71% and specificities of 71% and 69% respectively for the detection of mediastinal disease. Using both ratios in combination resulted in a sensitivity of 65% and a specificity of 88%. Concurrent benign lung disease was observed significantly more frequently in false-positive cases. CONCLUSION: SUVn/SUVpt and SUVn/SADn may be complimentary to conventional visual interpretation and SUV max measurement in the assessment of mediastinal disease in patients with NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/secundário , Aumento da Imagem/métodos , Neoplasias Pulmonares/patologia , Mediastino/patologia , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Reações Falso-Positivas , Feminino , Fluordesoxiglucose F18 , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Estadiamento de Neoplasias , Variações Dependentes do Observador , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Insights Imaging ; 5(2): 217-30, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24500656

RESUMO

OBJECTIVES: The aim was to assess the performance of low-dose non-contrast CT of the urinary tract (LD-CT) acquired at radiation exposures close to that of abdominal radiography using adaptive statistical iterative reconstruction (ASiR). METHODS: Thirty-three patients with clinically suspected renal colic were prospectively included. Conventional dose (CD-CT) and LD-CT data sets were contemporaneously acquired. LD-CT images were reconstructed with 40 %, 70 % and 90 % ASiR. Image quality was subjectively and objectively measured. Images were also clinically interpreted. RESULTS: Mean ED was 0.48 ± 0.07 mSv for LD-CT compared with 4.43 ± 3.14 mSv for CD-CT. Increasing the percentage ASiR resulted in a step-wise reduction in mean objective noise (p < 0.001 for all comparisons). Seventy % ASiR LD-CT images had higher diagnostic acceptability and spatial resolution than 90 % ASiR LD-CT images (p < 0.001). Twenty-seven calculi (diameter = 5.5 ± 1.7 mm), including all ureteric stones, were correctly identified using 70 % ASiR LD-CT with two false positives and 16 false negatives (diameter = 2.3 ± 0.7 mm) equating to a sensitivity and specificity of 72 % and 94 %. Seventy % ASiR LD-CT had a sensitivity and specificity of 87 % and 100 % for detection of calculi >3 mm. CONCLUSION: Reconstruction of LD-CT images with 70 % ASiR resulted in superior image quality than FBP, 40 % ASIR and 90 % ASIR. LD-CT with ASIR demonstrates high sensitivity and specificity for detection of calculi >3 mm. TEACHING POINTS: • Low-dose CT studies for urinary calculus detection were performed with a mean dose of 0.48 ± 0.07 mSv • Low-dose CT with 70 % ASiR detected calculi >3 mm with a sensitivity and specificity of 87 % and 100 % • Reconstruction with 70 % ASiR was superior to filtered back projection, 40 % ASiR and 90 % ASiR images.

14.
Adv Urol ; 2012: 606754, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22952473

RESUMO

Objective. To critically evaluate the current literature in an effort to establish the current role of radiologic imaging, advances in computed tomography (CT) and standard film radiography in the diagnosis, and characterization of urinary tract calculi. Conclusion. CT has a valuable role when utilized prudently during surveillance of patients following endourological therapy. In this paper, we outline the basic principles relating to the effects of exposure to ionizing radiation as a result of CT scanning. We discuss the current developments in low-dose CT technology, which have resulted in significant reductions in CT radiation doses (to approximately one-third of what they were a decade ago) while preserving image quality. Finally, we will discuss an important recent development now commercially available on the latest generation of CT scanners, namely, dual energy imaging, which is showing promise in urinary tract imaging as a means of characterizing the composition of urinary tract calculi.

15.
Clin Radiol ; 67(11): e27-30, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22964366

RESUMO

AIM: To investigate the validity of Courvoisier's sign, in the age of cross-sectional imaging and image analysis software by objectively measuring gallbladder volumes at magnetic resonance cholangiopancreatography (MRCP) in patients with and without biliary obstruction and to assess whether gallbladder volume is more significantly increased in patients with gallstone-related rather than non-gallstone-related biliary obstruction. MATERIALS AND METHODS: All MCRP investigations that were performed at a tertiary hepatobiliary centre over a 2-year period were analysed. The information recorded included the presence or absence of gallbladder stones as well as the presence and type of common bile duct (CBD) disease. Gallbladder volume was calculated from MRCP studies using image analysis software. RESULTS: Three hundred and ninety-four of 645 examined MRCPs (61.1%) were eligible for analysis. A statistically significant difference in mean gallbladder volume existed between the summated obstructive and non-obstructive groups (p < 0.001). In addition, a significant difference existed in mean gallbladder volume between those with CBD stones and non-gallstone CBD obstruction (p = 0.03). CONCLUSION: A significant difference was observed in gallbladder volumes in the group with biliary obstruction from choledocholithiasis compared with the group with biliary obstruction from other causes. Thus, objective measurement of gallbladder volume from modern cross-sectional imaging studies appears to validate Courvoisier's sign as a valuable clinical sign, which could be applied to modern imaging studies in distinguishing different causes of biliary obstruction in the jaundiced patient.


Assuntos
Colecistografia , Vesícula Biliar/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colecistografia/métodos , Colestase/diagnóstico por imagem , Colestase/patologia , Doenças do Ducto Colédoco/diagnóstico por imagem , Doenças do Ducto Colédoco/patologia , Feminino , Vesícula Biliar/anatomia & histologia , Cálculos Biliares/diagnóstico por imagem , Cálculos Biliares/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Adulto Jovem
16.
Br J Radiol ; 85(1017): 1222-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22919005

RESUMO

On 11 March 2011, the Richter scale 0.9-magnitude Tokohu earthquake and tsunami struck the northeast coast of Japan, resulting in widespread injury and loss of life. Compounding this tragic loss of life, a series of equipment and structural failures at the Fukushima Dai-ichi nuclear power plant (FDNP) resulted in the release of many volatile radioisotopes into the atmosphere. In this update, we detail currently available evidence about the nature of immediate radioactive exposure to FDNP workers and the general population. We contrast the nature of the radioactive exposure at FDNP with that which occurred at the Chernobyl power plant 25 years previously. Prediction of the exact health effects related to the FDNP release is difficult at present and this disaster provides the scientific community with a challenge to help those involved and to continue research that will improve our understanding of the potential complications of radionuclide fallout.


Assuntos
Terremotos/estatística & dados numéricos , Centrais Nucleares/estatística & dados numéricos , Exposição Ocupacional/estatística & dados numéricos , Monitoramento de Radiação/estatística & dados numéricos , Liberação Nociva de Radioativos/estatística & dados numéricos , Radioisótopos/administração & dosagem , Tsunamis/estatística & dados numéricos , Humanos , Japão , Oceanos e Mares
17.
Clin Radiol ; 67(8): 774-81, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22749384

RESUMO

AIM: To determine the diagnostic yield and clinical value of plain film of the abdomen (PFA) in Crohn's disease (CD) patients and to determine whether performance of PFA yields definitive diagnostic information or whether additional imaging examinations are required. MATERIALS AND METHODS: One hundred and seventy-seven CD patients underwent 643 PFAs during the period September 1992 to August 2008. Two radiologists blinded to the clinical details independently evaluated individual PFAs and/or their reports for abnormal findings using the following criteria: normal, small bowel (SB) findings; colonic findings, acute CD complications, extra-colonic findings; global assessment/impression. The results of additional imaging studies performed within 5 days of PFA were recorded and findings were analysed. RESULTS: A mean of 3.6 (range 1-22) PFAs was performed per patient during the study period. Almost 70% of films were normal (n = 449). SB abnormalities were detected in 21.8% (n = 140) PFAs; most commonly dilated loops (18.8%, n = 121) and mucosal oedema (5%, n = 32). Colonic abnormalities were present in 11.4% (n = 73); most commonly mucosal oedema (7.5%, n = 48) and dilated loops (5%, n = 32). Four cases of pneumoperitoneum were detected. There was no case of toxic megacolon. There was one case in which intra-abdominal abscess/collection was suspected and two cases of obstruction/ileus. Extracolonic findings (renal calculi, sacro-iliitis, etc.) were identified in 7.5% (n = 48). PFAs were followed by additional abdominal imaging within 5 days of PFA in 273/643 (42.5%) of cases. CONCLUSION: Despite the high rates of utilization of PFA in CD patients, there is a low incidence of abnormal findings (32.5%). Many of the findings are non-specific and clinically irrelevant and PFA is frequently followed by additional abdominal imaging examinations.


Assuntos
Doença de Crohn/diagnóstico por imagem , Radiografia Abdominal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Abdominal/estatística & dados numéricos , Estudos Retrospectivos , Sensibilidade e Especificidade , Adulto Jovem
18.
World J Surg ; 36(7): 1679-85, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22491816

RESUMO

BACKGROUND: Obesity is a well-established risk factor for acute pancreatitis. Increased visceral fat has been shown to exacerbate the pro-inflammatory milieu experienced by patients. This study aimed to investigate the relationship between the severity of acute pancreatitis and abdominal fat distribution parameters measured on computed tomography (CT) scan. METHODS: Consecutive patients admitted to Cork University Hospital with acute pancreatitis between January 2005 and December 2010 were evaluated for inclusion in the study. An open source image analysis software (Osirix, v 3.9) was used to calculate individual abdominal fat distribution parameters from CT scans by segmentation of abdominal tissues. RESULTS: A total of 214 patients were admitted with pancreatitis between January 2005 and December 2010. Sixty-two of these patients underwent a CT scan and were thus eligible for inclusion. Visceral fat volume was the volumetric fat parameter that had the most significant association with severe acute pancreatitis (P = 0.003). There was a significant association between visceral fat volume and subsequent development of systemic complications of severe acute pancreatitis (P = 0.003). There was a strong association between mortality and visceral fat volume (P = 0.019). Multivariate regression analysis, adjusted for gender, did not identify any individual abdominal fat distribution index as an independent risk factor for severe acute pancreatitis. CONCLUSIONS: Overall, estimation of abdominal fat distribution parameters from CT scans performed on patients with acute pancreatitis indicates a strong association between visceral fat, severe acute pancreatitis, and the subsequent development of systemic complications. These data suggest that visceral fat volume should be incorporated into future predictive scoring systems.


Assuntos
Gordura Abdominal/diagnóstico por imagem , Pancreatite/diagnóstico por imagem , Índice de Gravidade de Doença , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/complicações , Pancreatite/complicações , Pancreatite/mortalidade , Fatores de Risco , Tomografia Computadorizada por Raios X , Adulto Jovem
19.
Ir J Med Sci ; 181(1): 81-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21947685

RESUMO

BACKGROUND: The functional gastrointestinal disorders (FGIDs) are a heterogenous group of chronic conditions which cause troubling gastrointestinal symptoms. Though common and sometimes disabling, causing considerable social and economic burden, there is little recent literature on presentation or impact of FGIDs in Ireland. AIM: To describe the characteristics of patients with FGIDs at a tertiary referral clinic in Ireland. METHODS: A retrospective review of those attending a university hospital gastroenterology clinic with a special interest in FGIDs between January 1999 and July 2008 was performed. Data were mined from electronic outpatient records and clinic letters. RESULTS: A total of 1,909 patients were included. Of these patients, 41.2% (787 of 1,909) received a diagnosis of FGID. FGID patients were predominantly (70.14%) female and the average age at first presentation was 38.3 years. Of these, 76% (598 of 787) were referred from general practice; 35.8% (282 of 787) received onward referrals to other specialties. Nine hundred FGIDs were diagnosed. The most common FGID was irritable bowel syndrome (633 of 900, 70.3%). In the FGID group, 13.1% of patients (103 of 787) had more than one FGID diagnosis. Females received a definitive diagnosis of FGID faster than males; mean diagnostic latency: 5.3 versus 6.4 months (p < 0.05). Sixty-six percent (523 of 787) of FGID patients had non-gastrointestinal co-morbidities, with 315 (60.2%) of these having more than one co-morbidity. The burden of non-GI co-morbidity was significantly higher in patients with overlapping functional syndromes than in patients with single FGID (p < 0.05). CONCLUSIONS: In Ireland, FGIDs are common, represent a significant burden for the health-care system and deserve greater recognition and further research attention.


Assuntos
Gastroenteropatias/complicações , Gastroenteropatias/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Irlanda , Síndrome do Intestino Irritável/diagnóstico , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta/estatística & dados numéricos , Adulto Jovem
20.
Ir J Med Sci ; 181(3): 389-91, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20563757

RESUMO

BACKGROUND: Inferior vena cava (IVC) filter insertion is a commonly performed procedure for indications such as recurrent pulmonary emboli or contraindication to anticoagulation. Symptomatic duplication of the IVC is exceedingly rare with only a handful of cases being described in the literature. AIM: We report an unusual case of a patient with symptomatic duplication of the IVC. RESULT: A 53-year-old woman presented at our hospital for resection of a cerebral metastasis from a non-small cell lung cancer following a recent diagnosis of bilateral lower limb deep venous thrombosis. This required perioperative reversal of anticoagulation and IVC filter insertion. Conventional venography performed during filter insertion documented the existence of a duplicated IVC. CONCLUSION: We present a case of a symptomatic duplication of the IVC requiring filter insertion. We review the developmental anatomy of the IVC along with the diagnostic findings and management strategies available.


Assuntos
Filtros de Veia Cava , Veia Cava Inferior/anormalidades , Anticoagulantes , Contraindicações , Feminino , Humanos , Achados Incidentais , Pessoa de Meia-Idade , Implantação de Prótese , Trombose Venosa/terapia
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