RESUMEN
OBJECTIVES: Recently, the European Randomized Study of Screening for Prostate Cancer achieved a reduction in prostate cancer mortality by measuring serum prostate-specific antigen (PSA) levels. These results were not reproduced in the Spanish arm of European Randomized Study of Screening for Prostate Cancer. PSA contamination (opportunistic measurements outside the study) could decrease the study's contrasting power if performed in the control arm. We have calculated the long-term rate of PSA contamination and its effect on performing prostate biopsy and detecting cancer. MATERIAL AND METHODS: A total of 4,276 men were randomised (2,415 to the screening arm, 1,861 to the control arm) in the Spanish section of the European Randomized Study of Screening for Prostate Cancer. PSA measurements were not scheduled in the control arm. Sextant prostate biopsy was indicated if PSA levels were ≥3 ng/mL. All PSA readings performed outside the study were labelled as "PSA contamination". We calculated the rates of PSA contamination, biopsy implementation and cancer detection. RESULTS: The median age and follow-up time were 57 and 15.1 years, respectively. A total of 2,511 men underwent at least one PSA reading outside the study. PSA contamination at 5, 10 and 15 years was 22.0%, 47.1% and 66.3% in the screening arm, respectively, and 20.8%, 43.2% and 58.6% in the control arm, respectively (P<.0001). The biopsy rate at 5, 10 and 15 years was 19.3%, 22.6% and 24.1% (screening), respectively, and 1.0%, 3.6% and 7.1% (control), respectively (P<.0001). The PC detection rate was 6.7% (screening) and 4.3% (control; P=.0006). CONCLUSIONS: Although the cumulative PSA contamination was pronounced in the 2 study arms, the rate of prostate biopsies was low in the control arm. We therefore believe that the effect of PSA contamination on the study's statistical power should be limited.
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Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/diagnóstico , Anciano , Biopsia , Detección Precoz del Cáncer , Humanos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
OBJECTIVE: The role of prostate cancer (PC) screening is currently being questioned. The objective of the European Randomized Study of Screening for Prostate Cancer (ERSPC) was to demonstrate whether PC screening reduced mortality from this disease. The results from the Spanish branch of this study are presented: all-cause and cancer-specific mortality, the characteristics of the detected tumors, primary treatments and progression to advanced disease. MATERIAL AND METHODS: A total of 18,612 men, between the ages of 45 and 70, were invited to participate in the study, excluding those with a life expectancy of less than 10 years. The men were randomized to the screening arm (serum prostate-specific antigen [PSA] reading) or the control arm (no diagnostic tests). Randomized transrectal ultrasound-guided sextant prostate biopsies were indicated for the men in the screening arm with PSA levels ≥3ng/ml. The detected PCs were identified (stage and primary treatment), as well as the deaths that occurred (date and cause of death). RESULTS: The study was performed with 4276 men (2415 in the screening arm and 1861 in the control arm). The median age and serum PSA level were 57 years and 0.90ng/mL, respectively. The median follow-up time was 15.8 years. A total of 242 PCs were diagnosed, 162 (6.7%) in the screening arm and 80 (4.3%) in the control arm (P<.001). Of these, 214 (88.4%) had an organ-confined clinical stage at onset (91.4% in the screening arm vs. 82.5% in the control arm; P=.024). A total of 112 patients (46.3%) underwent radical prostatectomy, 53 (21.9%) underwent prostate radiation therapy, 24 (9.9%) underwent hormone therapy and 47 (19.4%) were kept under observation. A total of 18 PCs progressed to advanced disease (M+ or PSA levels >100ng/mL), with no differences between the study arms (P=.938). A total of 618 (14.5%) patients died during follow-up: 340 (14.1%) in the screening arm and 278 (14.9%) in the control arm, with no differences between the arms in terms of cancer-specific (P=.907) or all-cause (P=.399) mortality. The main causes of death were neoplasia (54.0%), cardiovascular (17.6%), respiratory (8.7%) and gastrointestinal (4.0%), with no difference between study arms. Of the 334 patients who died from neoplasia, only 12 (3.6%) died from PC. CONCLUSIONS: PC screening results in a shifting of the diagnosis towards earlier stages. Nevertheless, we have not demonstrated a benefit in terms of overall or cancer-specific survival after more than 15 years of follow-up. The low mortality from this disease in our community could be one of the main factors that explain these results.
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Detección Precoz del Cáncer , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/terapia , Anciano , Humanos , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
PURPOSE: To determine the predictive value of lymphangiography and computed tomography of the abdomen and pelvis for infradiaphragmatic involvement of Hodgkin's disease. METHODS AND METHODS: We retrospectively reviewed the findings on 125 patients with Hodgkin's disease treated at the University of Florida who underwent lymphangiography and staging laparotomy; 33 patients also underwent computed tomography of the abdomen and pelvis. The positive predictive value and negative predictive value were calculated for both studies. RESULTS: The positive predictive value of lymphangiography for paraaortic or pelvic disease was 35%, while the negative predictive value was 95%. The positive predictive value of computed tomography of the abdomen and pelvis for paraaortic or pelvic disease was 20%; the negative predictive value was 93%. There was no advantage in predicting paraaortic or pelvic disease when both studies were obtained as compared to either study alone. For splenic disease, the positive predictive value of computed tomography was 43%; the negative predictive value was 77%. Of the patients with a positive lymphangiography, 57% were found at laparotomy to have either no abdominal disease or upper abdominal disease only, with or without minimal splenic disease, making them reasonable candidates for radiotherapy alone. Of the patients with a negative lymphangiogram, 14% were found at laparotomy to have either lower abdominal disease or extensive splenic disease, and so were not good candidates for radiotherapy alone. CONCLUSION: We recommend laparotomy for patients who may be candidates for radiotherapy alone or combined modality therapy with limited chemotherapy.
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Enfermedad de Hodgkin/patología , Laparotomía , Linfografía , Tomografía Computarizada por Rayos X , Abdomen/patología , Enfermedad de Hodgkin/diagnóstico por imagen , Enfermedad de Hodgkin/epidemiología , Humanos , Estadificación de Neoplasias/métodos , Nueva Gales del Sur/epidemiología , Pelvis/diagnóstico por imagen , Pelvis/patología , Radiografía Abdominal , Estudios RetrospectivosRESUMEN
We evaluated the efficacy of six available oral contrast agents in improving visualization of bowel and surrounding structures on magnetic resonance imaging of the abdomen and pelvis. Five volunteers were examined without oral contrast (baseline) and, on separate occasions, after ingestion of 600-900 cc of two positive contrasts [12.5% weight-to-volume (w/v) corn oil emulsion (COE), Redi Cat (EZ-Em Corp., Westbury, NY) mixed with 1% ferric ammonium citrate (FAC)] and four negative contrasts [220%, 105%, 85%, 60% w/v barium sulfate (Liquid HD, Liquid Polybar Plus, HD 85, reconstituted EZ Pake; EZ-Em Corp., Westbury, NY)]. Spin-echo axial and coronal T1-weighted and axial T2-weighted images were obtained in the abdomen and pelvis. Three radiologists blindly graded the images for improved visualization of bowel and surrounding structures. Data were analyzed for statistical significance using the General Linear Models algorithm. In the upper abdomen (stomach, duodenum, liver, and pancreas), COE yielded the highest mean scores (p < .0001), followed by 220% w/v barium. For the lower abdomen (ileum, colon), 220% w/v barium yielded the highest scores (p < .0001) and COE was much worse. The higher density barium preparations (220% and 105% w/v) yielded higher scores than their lower density counterparts (85% and 60%). All contrasts improved visualization of the retroperitoneum and spleen, but no one agent was best. All agents tested are superior to no agent at all. For visualization of the upper abdomen, 12.5% COE performed best. For visualization of the lower abdomen, 220% w/v barium performed best. For concurrent evaluation of both areas with one agent, 220% w/v barium performed best.
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Abdomen/anatomía & histología , Medios de Contraste/administración & dosificación , Imagen por Resonancia Magnética , Administración Oral , Adulto , Sulfato de Bario/administración & dosificación , Sulfato de Bario/efectos adversos , Medios de Contraste/efectos adversos , Aceite de Maíz/administración & dosificación , Aceite de Maíz/efectos adversos , Femenino , Compuestos Férricos/administración & dosificación , Compuestos Férricos/efectos adversos , Humanos , Masculino , Compuestos de Amonio Cuaternario/administración & dosificación , Compuestos de Amonio Cuaternario/efectos adversosRESUMEN
This study was conducted to compare the sensitivity and specificity of abdominal magnetic resonance imaging using oral superparamagnetic iron oxide with oral contrast-enhanced computed tomography in the detection of GI pathology. Overall sensitivity was calculated to be 83% for OECT compared to 67% by SPIO MRI. Specificity for OECT was 68% compared to 89% for SPIO MRI. The results from imaging with superparamagnetic iron oxide and imaging with oral contrast-enhanced computed tomography were in agreement in 14 subjects who had normal gastrointestinal tracts. In the remaining 16 patients, eight pathologic entities were detected by both modalities whereas 15 abnormalities were seen by only one modality. Superparamagnetic iron oxide magnetic resonance imaging was helpful in discriminating normal bowel from solid lesions and in detecting subtle gastrointestinal tract mass effect. In 30 consecutively studied patients suspected of having GI pathology, OECT was more sensitive than SPIO MRI in detecting abdominal pathology. Conversely, SPIO MRI was more specific than OECT.
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Medios de Contraste/administración & dosificación , Enfermedades Gastrointestinales/diagnóstico , Hierro , Imagen por Resonancia Magnética , Óxidos , Tomografía Computarizada por Rayos X , Administración Oral , Óxido Ferrosoférrico , Enfermedades Gastrointestinales/diagnóstico por imagen , Humanos , Sensibilidad y EspecificidadRESUMEN
The purpose of this study was to compare the patient tolerance and efficacy, as magnetic resonance imaging negative oral contrast agents, of a mixture of clay compound bentonite and low density barium sulfate suspension with that of higher density barium sulfate. Twenty patients were randomized into two groups: 10 patients receiving a mixture of low concentration 60% w/v barium sulfate plus 2.5% w/v bentonite, and 10 patients receiving 220% w/v barium sulfate Liuqid-HD (E-Z-EM, Westbury, NY). Post-contrast Spin-echo (SE) T1- and T2-weighted images (WI) were obtained on a 1.0T magnet. Two independent readers scored the overall intraluminal signal intensity and delineation of the gastrointestinal tract and adjacent organs. Patient acceptance was evaluated via a short questionnaire, by recording spontaneous comments and documenting the quantity of contrast agent ingested. There was greater intraluminal bowel signal reduction and organ delineation with 220% w/v barium than with the barium-bentonite mixture on both SE T1WI (p = 0.03) and SE T2WI (p = 0.42). With both agents there was greater signal reduction on SE T2WI than SE T1WI. Higher scores for organ delineation for both contrast agents were seen with SE T1WI. With 220% w/v barium, there was significantly better delineation of the pancreatic body (p = 0.02) and pancreatic tail (p = 0.02) on T1WI compared with SE T2WI. With the barium-bentonite mixture, SE T1WI showed improved delineation of jejunum compared with SE T2WI (p = 0.03). There were no statistically significant differences between the volume of contrast ingested in the two groups. Abdominal cramps were recorded for one patient in each group. These results suggest that barium-bentonite mixture, although useful as a negative gastro-intestinal contrast agent, is not as effective as 220% w/v barium. Further studies with a larger patient population and concentration optimization studies are needed.
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Sulfato de Bario , Bentonita , Medios de Contraste , Sistema Digestivo/anatomía & histología , Imagen por Resonancia Magnética , Abdomen/anatomía & histología , Administración Oral , Sulfato de Bario/administración & dosificación , Bentonita/administración & dosificación , Humanos , Pelvis/anatomía & histología , Estadísticas no ParamétricasRESUMEN
MR imaging is used in the spleen primarily to supplement CT scan studies. Because of its multiplanar capabilities and potential characterization of lesions on the basis of signal features, however, MR can provide important diagnostic information. This article reviews appropriate imaging techniques and the MR appearance of congenital anomalies, trauma, inflammatory and vascular disease, and neoplasms.
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Imagen por Resonancia Magnética , Bazo/anatomía & histología , Enfermedades del Bazo/diagnóstico , Humanos , Bazo/patologíaRESUMEN
A prospective, randomized study was performed to examine the image quality of varying reduced doses of an intravenous (IV) nonionic contrast agent (ioversol, 320 mg/ml organically bound iodine) compared with the quality obtained using the maximum permissible dose (150 ml) of the same agent. Forty-five patients referred for abdominal-pelvic computed tomography (CT) scan were randomized into five groups to receive contrast doses equivalent to 100, 75, 65, 50, or 30% of 150 ml of contrast agent. The images were scored for diagnostic image quality in eight anatomical regions of interest and, in addition, quantitative analysis of density measurements were performed in the abdominal aorta and inferior vena cava. There was no statistically significant difference in either image quality, in any anatomical region, or in vascular density measurements between the group receiving 100% and the group receiving 75% of 150 ml of nonionic contrast agent. Patients receiving 65% and lower doses demonstrated a statistically significant decrease in enhancement, although all scans were diagnostically adequate. This study demonstrates that dynamic abdominal and pelvic CT scans obtained using a reduced dose of nonionic IV contrast agent are equivalent in diagnostic image quality compared with those scans obtained with the higher permissible dose of the same agent.
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Medios de Contraste/administración & dosificación , Pelvis/diagnóstico por imagen , Radiografía Abdominal , Tomografía Computarizada por Rayos X/métodos , Ácidos Triyodobenzoicos/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Aorta Abdominal/diagnóstico por imagen , Femenino , Venas Hepáticas/diagnóstico por imagen , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Intensificación de Imagen Radiográfica , Vena Cava Inferior/diagnóstico por imagenRESUMEN
BACKGROUND: To present the long-term results of a prostate cancer (PC) screening trial conducted in a Mediterranean setting. METHODS: A total of 4276 men aged 45-70 years were randomized to screening arm (PSA test performed) and control arm (no tests). Transrectal ultrasonography-guided sextant prostate biopsy was conducted when PSA > or = 3 ng ml(-1). Date and cause of death were retrieved from death certificates. PC incidence, and disease-specific and overall mortality curves were plotted and comparison between arms was made. Analysis of causes of death was also performed. RESULTS: Median age at randomization was 57.0 years. Median follow-up time was 15.2 years. A total of 241 men were diagnosed with PC, 161 (6.7%) in the screening arm and 80 (4.3%) in the control arm (P<0.01). Eventually, 554 men (13%) died. No difference in all-cause mortality was found between arms (P=0.34). Only 10 men (10/4276, 0.23%) died from PC, no differences between arms (P=0.67). Overall, the main causes of death were malignancy (54.2%), cardiovascular (17.9%) and respiratory (9.2%) diseases. Main cancer causes of death were lung and bronchus cancer (37.2%), colorectum (15.0%) and stomach (9.0%) cancer. PC only accounted for 3.0% of all malignant causes of death (ranked 10th). CONCLUSIONS: Our study failed to demonstrate benefits of PC screening in terms of all-cause and PC-specific mortality after a median follow-up of 15 years. The limited sample size and the low long-term PC mortality observed in our setting were probably the most important factors to explain these results.
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Neoplasias de la Próstata/epidemiología , Neoplasias de la Próstata/mortalidad , Anciano , Biopsia/métodos , Detección Precoz del Cáncer/métodos , Humanos , Incidencia , Calicreínas/metabolismo , Masculino , Persona de Mediana Edad , Antígeno Prostático Específico/metabolismo , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/metabolismo , España/epidemiología , Factores de TiempoRESUMEN
Two patients presenting with acute onset of left lower abdominal pain due to infarcted epiploic appendages are the subject of this report. Computed tomography (CT) in both cases showed localized pericolic inflammatory changes corresponding to the location of infarcted epiploic appendages on the serosal aspect of the descending colon or sigmoid. The clinical and radiological findings of this entity are briefly described.
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Colon/irrigación sanguínea , Infarto/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Dolor Abdominal/etiología , Adulto , Anciano , Colon/diagnóstico por imagen , Femenino , Humanos , Infarto/complicaciones , MasculinoRESUMEN
OBJECTIVE: The purpose of this study was to evaluate whether ferumoxides-enhanced MR imaging of focal hepatic lesions provides distinctive signal intensity and lesion-to-liver contrast changes for benign and malignant lesions, helping to further characterize and differentiate these lesions. MATERIALS AND METHODS: Data analysis was performed on 70 patients, with previously identified focal hepatic lesions, who underwent MR imaging of the liver before and after IV administration of ferumoxides (10 micromol Fe/kg). Lesions analyzed with pathologically proven diagnoses included metastases (n = 40), hepatocellular carcinoma (n = 11), cholangiocarcinoma (n = 6), hemangioma (n = 4), focal nodular hyperplasia (n = 6), and hepatocellular adenoma (n = 3). Response variables measured and statistically compared included the percentage of signal-intensity change and lesion-to-liver contrast. RESULTS: Focal nodular hyperplasia showed significant signal intensity loss on ferumoxides-enhanced T2-weighted images (mean, -43%+/-6.7%, p < 0.01). All other lesion groups showed no statistically significant change in signal intensity on ferumoxides-enhanced T2-weighted images, although signal intensity loss was seen in some individual hepatocellular adenomas (mean, -6.6%+/-24.0%) and hepatocellular carcinomas (mean, -3.3%+/-10.3%). All lesions, with the exception of hepatocellular carcinoma, had a marked increase in lesion-to-liver contrast on ferumoxides-enhanced T2-weighted images, which was statistically significant for metastases and hemangioma (p < 0.02). CONCLUSION: Focal nodular hyperplasia shows significant decrease in signal intensity on ferumoxides-enhanced T2-weighted images, which may aid in the differentiation of focal nodular hyperplasia from other focal hepatic lesions. Other lesions, namely, hepatocellular adenoma and carcinoma, can have reticuloendothelial uptake, but usually to a lesser degree than that of focal nodular hyperplasia.
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Medios de Contraste , Hierro , Hepatopatías/patología , Neoplasias Hepáticas/patología , Imagen por Resonancia Magnética/métodos , Óxidos , Adulto , Anciano , Dextranos , Diagnóstico Diferencial , Femenino , Óxido Ferrosoférrico , Humanos , Nanopartículas de Magnetita , Estudios RetrospectivosRESUMEN
Pelvic magnetic resonance (MR) imaging is limited by lack of an effective bowel contrast agent. This study was performed to evaluate the efficacy of rectally administered barium sulfate as a contrast agent in pelvic MR imaging. Thirty-two patients were studied retrospectively to evaluate anatomic definition of the rectosigmoid colon. A commercially available barium sulfate suspension was administered rectally in 19 patients. Thirteen patients were imaged without barium. In the latter patients, anatomic definition of the rectum and sigmoid colon was poor to fair with all pulse sequences. Delineation of the rectum and sigmoid colon improved in patients who received rectal barium, owing to distention and marking of the bowel by the predominantly low-signal-intensity barium. Barium is a safe, inexpensive negative contrast agent for bowel that may improve pelvic MR imaging.
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Sulfato de Bario , Enema , Imagen por Resonancia Magnética , Pelvis/patología , Adolescente , Adulto , Anciano , Femenino , Humanos , Intestinos/patología , Masculino , Persona de Mediana EdadRESUMEN
Many focal splenic lesions may appear to be cystic at cross-sectional imaging. In this article, the following types of cystic splenic masses are discussed: congenital (true cyst), inflammatory (abscesses, hydatid cyst), vascular (infarction, peliosis), posttraumatic (hematoma, false cyst), and neoplastic (hemangioma, lymphangioma, lymphoma, metastasis). The key findings at ultrasound, computed tomography, and magnetic resonance imaging can be correlated with underlying gross and microscopic pathologic findings. Although tissue sampling is still required in many cases to yield a definitive diagnosis, recognition and understanding of the spectrum of imaging and pathologic features of these lesions often help narrow the differential diagnosis.
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Quistes/diagnóstico , Enfermedades del Bazo/diagnóstico , Quistes/diagnóstico por imagen , Quistes/patología , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética , Enfermedades del Bazo/diagnóstico por imagen , Enfermedades del Bazo/patología , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
We present a case of von Hippel-Lindau disease with special reference to the findings in MR imaging of visceral abdominal manifestations.
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Imagen por Resonancia Magnética , Enfermedad de von Hippel-Lindau/diagnóstico , Adulto , Carcinoma de Células Renales/diagnóstico , Femenino , Humanos , Enfermedades Renales Quísticas/diagnóstico , Neoplasias Renales/diagnóstico , Quiste Pancreático/diagnóstico , Tomografía Computarizada por Rayos XRESUMEN
The use of magnetic resonance (MR) imaging for evaluating the abdomen and pelvis has been limited by the lack of a suitable contrast agent. The purpose of this study was to compare axial MR imaging after rectal barium administration with computed tomography (CT) for delineation of normal anatomy and lesions of the pelvis. MR images and CT scans of 11 patients were studied retrospectively and independently by four radiologists. No substantial differences in the visualization of normal bowel, iliac vessels, lymph nodes, bladder, prostate, seminal vesicles, uterus, and cervix and in detection of abnormalities were seen between CT scans and axial MR images obtained after barium administration. This preliminary study suggests that axial MR imaging with rectal barium is a useful alternative to CT in evaluating pelvic disease.
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Sulfato de Bario , Imagen por Resonancia Magnética , Neoplasias Pélvicas/diagnóstico , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Enema , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pélvicas/diagnóstico por imagen , Estudios RetrospectivosRESUMEN
PURPOSE: Our goal was to determine the efficacy of a dedicated protocol for pancreatic MRI using fat suppression, oblique plane orientation, and barium as an oral contrast agent. METHOD: Fifty-two patients were enrolled in our study. In each patient, the stomach and duodenum were opacified with 300 ml oral barium. In all patients conventional SE T1- and T2-weighted images and fat-suppressed axial and oblique T1-weighted images of the upper abdomen and the pancreas, respectively, were obtained. The different T1-weighted sequences were compared for visualization of the pancreas and for lesion conspicuity. Oblique images were obtained in a plane parallel to the overall axis of the pancreas. All sequences were qualitatively assessed by two independent blinded readers and statistically compared. RESULTS: The combination of fat suppression and oblique imaging significantly improved the visualization of the different anatomic portions of the normal pancreas as well as pathologic findings in the pancreas in 70-92% of the cases compared with conventional axial T1-weighted imaging (p < 0.001) and in 52-75% of the cases compared with axial fat-suppressed T1-weighted imaging (p < 0.001), respectively. Increased image noise and blurring artifacts resulted in slight image degradation after Gd-DTPA administration. Barium as a duodenal contrast agent was beneficial for delineation of the pancreatic head from the adjacent bowel structures. CONCLUSION: In pancreatic imaging, fat-suppressed T1-weighted imaging is superior to conventional T1-weighted imaging, and oblique imaging is superior to axial imaging. Intravenous Gd-DTPA administration was useful only in selected cases.
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Tejido Adiposo/patología , Sulfato de Bario , Medios de Contraste , Imagen por Resonancia Magnética , Páncreas/patología , Enfermedades Pancreáticas/diagnóstico , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Artefactos , Sulfato de Bario/administración & dosificación , Medios de Contraste/administración & dosificación , Duodeno/patología , Femenino , Gadolinio DTPA/administración & dosificación , Humanos , Aumento de la Imagen/métodos , Inyecciones Intravenosas , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/diagnóstico , Método Simple Ciego , Estómago/patologíaRESUMEN
The authors conducted a preliminary evaluation of the potential of superparamagnetic iron oxide as contrast material for delineation of the bowel. Ten patients with various pancreatic diseases and 18 patients with suspected retroperitoneal disease underwent T1- and T2-weighted MR imaging before and after contrast material was administered. Two radiologists reviewed randomized images and scored them for depiction of anatomic structures and abnormalities. In most patients, postcontrast T1-weighted images showed improved delineation of the retroperitoneal small bowel (duodenum), stomach, and pancreas. Postcontrast T2-weighted images showed improved delineation of retroperitoneal small bowel, para-aortic region, peripancreatic fat, and renal veins. There was no improvement in delineation of retroperitoneal diseases, except for lymphadenopathy, which was better seen on both T1- and T2-weighted postcontrast images. Preliminary results suggest that superparamagnetic iron oxide is a useful contrast agent for delineating some normal retroperitoneal structures, lymphadenopathy, and pancreatic disease and that it is less useful in evaluating other retroperitoneal masses.
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Medios de Contraste , Aumento de la Imagen/métodos , Hierro , Imagen por Resonancia Magnética , Óxidos , Enfermedades Pancreáticas/diagnóstico , Neoplasias Retroperitoneales/diagnóstico , Tejido Adiposo/patología , Administración Oral , Aorta/patología , Medios de Contraste/administración & dosificación , Medios de Contraste/efectos adversos , Dextranos , Duodeno/patología , Óxido Ferrosoférrico , Humanos , Intestino Delgado/patología , Hierro/administración & dosificación , Hierro/efectos adversos , Ganglios Linfáticos/patología , Imagen por Resonancia Magnética/métodos , Nanopartículas de Magnetita , Óxidos/administración & dosificación , Óxidos/efectos adversos , Páncreas/patología , Espacio Retroperitoneal/patología , Estudios RetrospectivosRESUMEN
Preliminary data suggest that barium sulfate suspension is a potentially useful negative gastrointestinal contrast agent for MR imaging. To evaluate this hypothesis in a controlled fashion, abdominal and pelvic MR studies of 10 normal volunteers were performed before and after both oral (600-900 ml) and rectal (400 ml) administration of barium. Standard spin-echo coronal T1-, axial T1-, proton density-, and T2-weighted images were obtained at 1.5 T. Images obtained were randomized and interpreted by three observers, who evaluated bowel visualization and delineation of normal anatomy. Bowel segments evaluated were stomach, duodenum, proximal small bowel, proximal colon, distal colon, and rectum. Anatomic structures examined were pancreatic head, pancreatic body, pancreatic tail, retroperitoneum, spleen, liver, pelvic side walls, uterus, vagina, bladder, prostate, and seminal vesicles. Data concerning barium tolerance and safety were recorded. Descriptive, percent change, and kappa statistics were analyzed. Pairwise agreement techniques and repeated measures analysis of variance were performed. This statistical assessment showed a significant improvement in both bowel visualization (59-123% improvement, depending on the segment) and delineation of normal anatomy (23-68% improvement, depending on the structure) after barium administration, particularly on T1-weighted images. In addition, barium was a well-tolerated and safe contrast agent that did not produce artifacts. Our results show that barium sulfate is a useful negative gastrointestinal contrast agent for MR because it improves bowel visualization and delineation of abdominal anatomy, particularly on T1-weighted sequences.
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Sulfato de Bario , Sistema Digestivo/anatomía & histología , Imagen por Resonancia Magnética , Abdomen/anatomía & histología , Administración Oral , Administración Rectal , Adulto , Sulfato de Bario/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pelvis/anatomía & histologíaRESUMEN
The iliopsoas compartment is an extraperitoneal space that contains the greater psoas, smaller psoas, and iliac muscles. Many pathologic processes may involve the iliopsoas compartment, including inflammatory, hemorrhagic, and neoplastic conditions. Psoas muscle infection is usually due to direct extension from contiguous structures. With the decreasing incidence of tuberculosis, the majority of psoas abscesses now encountered have a pyogenic origin. Hemorrhage into the psoas muscle can be spontaneous or secondary to various conditions. Neoplastic involvement of the psoas muscle is usually due to contiguous spread and is rarely primary. With the refinement of imaging modalities, there has been increased recognition of diseases that involve the iliopsoas compartment. Although these conditions may look similar radiologically, they can be correctly diagnosed by combining the radiologic findings with the clinical history. Biopsy is effective in diagnosis of such conditions; aspiration and drainage are effective in both diagnosis and therapy.