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1.
Radiographics ; 44(8): e230174, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-39024175

RESUMEN

Pathologic conditions of the biliary system, although common, can be difficult to diagnose clinically. Challenges in biliary imaging include anatomic variants and the dynamic nature of the biliary tract, which can change with age and intervention, blurring the boundaries of normal and abnormal. Choledochal cysts can have numerous appearances and are important to diagnose given the risk of cholangiocarcinoma potentially requiring surgical resection. Choledocholithiasis, the most common cause of biliary dilatation, can be difficult to detect at US and CT, with MRI having the highest sensitivity. However, knowledge of the imaging pitfalls of MRI and MR cholangiopancreatography is crucial to avoid misinterpretation. Newer concepts in biliary tract malignancy include intraductal papillary biliary neoplasms that may develop into cholangiocarcinoma. New paradigms in the classification of cholangiocarcinoma correspond to the wide range of imaging appearances of the disease and have implications for prognosis. Accurately staging cholangiocarcinoma is imperative, given expanding curative options including transplant and more aggressive surgical options. Infections of the biliary tree include acute cholangitis or recurrent pyogenic cholangitis, characterized by obstruction, strictures, and central biliary dilatation. Inflammatory conditions include primary sclerosing cholangitis, which features strictures and fibrosis but can be difficult to differentiate from secondary causes of sclerosing cholangitis, including more recently described entities such as immunoglobulin G4-related sclerosing cholangitis and COVID-19 secondary sclerosing cholangitis. The authors describe a wide variety of benign and malignant biliary tract abnormalities, highlight differentiating features of the cholangitides, provide an approach to interpretation based on the pattern of imaging findings, and discuss pearls and pitfalls of imaging to facilitate accurate diagnosis. ©RSNA, 2024 Supplemental material is available for this article.


Asunto(s)
Sistema Biliar , Humanos , Sistema Biliar/diagnóstico por imagen , Sistema Biliar/patología , Enfermedades de las Vías Biliares/diagnóstico por imagen , Diagnóstico Diferencial
2.
Artículo en Inglés | MEDLINE | ID: mdl-39379060

RESUMEN

OBJECTIVE: The aim of the study is to assess the validity of a recently published consensus magnetic resonance imaging (MRI) diagnostic algorithm for differentiating degenerating leiomyomas from uterine sarcomas and other atypical appearing uterine malignancies. METHODS: Atypical uterine masses on pelvic MRI were identified using a radiology report search engine and teaching files with the keywords "atypical leiomyoma," "atypical fibroid," and "sarcoma." All cases were pathology-proven. Two radiologists blinded to clinical, surgical, and pathologic reports retrospectively and independently reviewed 40 pelvic MRI examinations dated 1/2007-9/2022 to determine whether the masses appeared benign or malignant, using the 2022 consensus atypical uterine mass flow chart. Imaging features assessed included intermediate/high signal intensity (SI) at T2-weighted imaging, high diffusion weighted imaging SI (equal or higher SI than endometrium or lymph nodes on high b value imaging), apparent diffusion coefficient (ADC) value ≤0.905 × 10-3 mm2/s, peritoneal metastases, and abnormal lymph nodes. RESULTS: Among the 40 atypical uterine mass cases reviewed, 24 masses were benign (22 leiomyomas, 1 adenomyoma, and 1 borderline ovarian tumor) and 16 masses were malignant (6 leiomyosarcomas, 6 carcinosarcomas, 2 endometrial stromal sarcomas, 1 high-grade adenosarcoma, and 1 low-grade uterine sarcoma). Sensitivity, specificity, positive predictive value, and negative predictive value of whether a mass was benign or malignant were 75%, 95.8%, 92.3%, and 85% for reader 1, and 81.2%, 91.7%, 86.7%, and 88% for reader 2, respectively. Interrater agreement was strong, with a kappa statistic of 0.89. When excluding nonleiomyosarcoma uterine malignancies, sensitivity and negative predictive value improved to 100%. CONCLUSIONS: The new consensus pelvic MRI algorithm for evaluating atypical uterine masses has good specificity, sensitivity, positive predictive value, and negative predictive value for determining malignancy, particularly for uterine sarcomas that are leiomyosarcomas. However, if ADC value is near but not below 0.905 × 10-3 mm2/s, the mass may still be malignant, especially if a b value lower than 1000 is used. If the atypical uterine mass is predominantly endometrial, morphological features on T2 and postgadolinium sequences should guide suspicion, as some atypical appearing nonleiomyosarcoma uterine malignancies may have an ADC value greater than 0.905 × 10-3 mm2/s.

3.
Radiographics ; 43(4): e220113, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36893051

RESUMEN

The commonly taught tenet that intratesticular lesions are always malignant and extratesticular scrotal lesions are always benign is a simplistic statement that erroneously minimizes the significance of extratesticular scrotal masses and their diagnosis. Yet, disease in the extratesticular space is commonly encountered by clinicians and radiologists and is often a source of uncertainty in diagnosis and management. Given the embryologically rooted complex anatomy of this region, a wide range of pathologic conditions is possible. Radiologists may not be familiar with some of these conditions; further, many of these lesions can have a specific sonographic appearance, allowing accurate diagnosis that can minimize surgical intervention. Lastly, malignancies can occur in the extratesticular space-although this is less common than in the testicles-and proper recognition of findings that warrant additional imaging or surgery is critical in optimizing outcomes. The authors present a compartmental anatomic framework for differential diagnosis of extratesticular scrotal masses and provide a comprehensive illustrative display of many of the pathologic conditions that can be encountered to familiarize radiologists with the sonographic appearances of these lesions. They also review management of these lesions and scenarios where US may not be definitive in diagnosis and selective use of scrotal MRI can be helpful. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.


Asunto(s)
Escroto , Neoplasias Testiculares , Masculino , Humanos , Diagnóstico Diferencial , Escroto/diagnóstico por imagen , Escroto/patología , Ultrasonografía , Neoplasias Testiculares/patología
4.
Radiographics ; 43(6): e220181, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37227944

RESUMEN

Quantitative imaging biomarkers of liver disease measured by using MRI and US are emerging as important clinical tools in the management of patients with chronic liver disease (CLD). Because of their high accuracy and noninvasive nature, in many cases, these techniques have replaced liver biopsy for the diagnosis, quantitative staging, and treatment monitoring of patients with CLD. The most commonly evaluated imaging biomarkers are surrogates for liver fibrosis, fat, and iron. MR elastography is now routinely performed to evaluate for liver fibrosis and typically combined with MRI-based liver fat and iron quantification to exclude or grade hepatic steatosis and iron overload, respectively. US elastography is also widely performed to evaluate for liver fibrosis and has the advantage of lower equipment cost and greater availability compared with those of MRI. Emerging US fat quantification methods can be performed along with US elastography. The author group, consisting of members of the Society of Abdominal Radiology (SAR) Liver Fibrosis Disease-Focused Panel (DFP), the SAR Hepatic Iron Overload DFP, and the European Society of Radiology, review the basics of liver fibrosis, fat, and iron quantification with MRI and liver fibrosis and fat quantification with US. The authors cover technical requirements, typical case display, quality control and proper measurement technique and case interpretation guidelines, pitfalls, and confounding factors. The authors aim to provide a practical guide for radiologists interpreting these examinations. © RSNA, 2023 See the invited commentary by Ronot in this issue. Quiz questions for this article are available in the supplemental material.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Sobrecarga de Hierro , Hepatopatías , Humanos , Hierro , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Hígado/diagnóstico por imagen , Hígado/patología , Imagen por Resonancia Magnética/métodos , Hepatopatías/patología , Sobrecarga de Hierro/diagnóstico por imagen , Diagnóstico por Imagen de Elasticidad/métodos , Radiólogos , Biomarcadores
5.
Eur Radiol ; 32(5): 3220-3235, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34846566

RESUMEN

OBJECTIVES: Imaging evaluation is an essential part of treatment planning for patients with ovarian cancer. Variation in the terminology used for describing ovarian cancer on computed tomography (CT) and magnetic resonance (MR) imaging can lead to ambiguity and inconsistency in clinical radiology reports. The aim of this collaborative project between Society of Abdominal Radiology (SAR) Uterine and Ovarian Cancer (UOC) Disease-focused Panel (DFP) and the European Society of Uroradiology (ESUR) Female Pelvic Imaging (FPI) Working Group was to develop an ovarian cancer reporting lexicon for CT and MR imaging. METHODS: Twenty-one members of the SAR UOC DFP and ESUR FPI working group, one radiology clinical fellow, and two gynecologic oncology surgeons formed the Ovarian Cancer Reporting Lexicon Committee. Two attending radiologist members of the committee prepared a preliminary list of imaging terms that was sent as an online survey to 173 radiologists and gynecologic oncologic physicians, of whom 67 responded to the survey. The committee reviewed these responses to create a final consensus list of lexicon terms. RESULTS: An ovarian cancer reporting lexicon was created for CT and MR Imaging. This consensus-based lexicon has 6 major categories of terms: general, adnexal lesion-specific, peritoneal carcinomatosis-specific, lymph node-specific, metastatic disease -specific, and fluid-specific. CONCLUSIONS: This lexicon for CT and MR imaging evaluation of ovarian cancer patients has the capacity to improve the clarity and consistency of reporting disease sites seen on imaging. KEY POINTS: • This reporting lexicon for CT and MR imaging provides a list of consensus-based, standardized terms and definitions for reporting sites of ovarian cancer on imaging at initial diagnosis or follow-up. • Use of standardized terms and morphologic imaging descriptors can help improve interdisciplinary communication of disease extent and facilitate optimal patient management. • The radiologists should identify and communicate areas of disease, including difficult to resect or potentially unresectable disease that may limit the ability to achieve optimal resection.


Asunto(s)
Neoplasias Ováricas , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Neoplasias Ováricas/diagnóstico por imagen , Tomografía Computarizada por Rayos X
6.
BMC Urol ; 22(1): 107, 2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-35850677

RESUMEN

INTRODUCTION: The Prostate Imaging Reporting and Data System (PIRADS) has shown promise in improving the detection of Gleason grade group (GG) 2-5 prostate cancer (PCa) and reducing the detection of indolent GG1 PCa. However, data on the performance of PIRADS in Black and Hispanic men is sparse. We evaluated the accuracy of PIRADS scores in detecting GG2-5 PCa in White, Black, and Hispanic men. METHODS: We performed a multicenter retrospective review of biopsy-naïve Black (n = 108), White (n = 108), and Hispanic (n = 64) men who underwent prostate biopsy (PB) following multiparametric MRI. Sensitivity and specificity of PIRADS for GG2-5 PCa were calculated. Race-stratified binary logistic regression models for GG2-5 PCa using standard clinical variables and PIRADS were used to calculate area under the receiver operating characteristics curves (AUC). RESULTS: Rates of GG2-5 PCa were statistically similar between Blacks, Whites, and Hispanics (52.8% vs 42.6% vs 37.5% respectively, p = 0.12). Sensitivity was lower in Hispanic men compared to White men (87.5% vs 97.8% respectively, p = 0.01). Specificity was similar in Black versus White men (21.6% vs 27.4%, p = 0.32) and White versus Hispanic men (27.4% vs 17.5%, p = 0.14). The AUCs of the PIRADS added to standard clinical data (age, PSA and suspicious prostate exam) were similar when comparing Black versus White men (0.75 vs 0.73, p = 0.79) and White versus Hispanic men (0.73 vs 0.59, p = 0.11). The AUCs for the Base model and PIRADS model alone were statistically similar when comparing Black versus White men and White versus Hispanic men. CONCLUSIONS: The accuracy of the PIRADS and clinical data for detecting GG2-5 PCa seems statistically similar across race. However, there is concern that PIRADS 2.0 has lower sensitivity in Hispanic men compared to White men. Prospective validation studies are needed.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Biopsia , Etnicidad , Humanos , Biopsia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Antígeno Prostático Específico , Neoplasias de la Próstata/diagnóstico
7.
Emerg Radiol ; 29(5): 833-843, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35639185

RESUMEN

PURPOSE: Hemoperitoneum caused by ovarian cyst rupture may necessitate intervention. The literature is lacking in descriptions of CT findings that help guide patient management. The purpose of this study is to consider CT findings associated with a need for intervention (surgical or interventional radiology management) versus conservative treatment (observation, pain management, and blood transfusions). METHODS: Two radiologists retrospectively and independently reviewed 103 CTs of pre-menopausal women who presented with acute hemoperitoneum related to ruptured ovarian cysts between January 2010 and January 2019. The following imaging features were assessed: ovarian cyst characteristics, sentinel clot, contrast extravasation, and hemoperitoneum size. Findings were correlated with patient demographics, clinical parameters, and management with surgery/interventional radiology procedure (intervention group) versus conservative management (conservative group). RESULTS: Of the 103 patients with hemoperitoneum from cyst rupture, 16% (n = 16) required intervention, and 84% underwent conservative treatment (n = 87). Length of stay (p = .008) was higher in the intervention group. Statistically significant CT findings in the intervention versus conservative group included (p-value reader 1/p-value reader 2) greatest AP dimension of hemoperitoneum (p = .001/p = 0.02), posterior cul-de-sac AP dimension (p = 0.03/p = .006), total cul-de-sac AP dimension (p = .002/p = .007), and number of spaces with hemoperitoneum (p = .01/p = .02). There was good to excellent inter-reader agreement for these findings (ICC 0.68-0.91). Active contrast extravasation was significant for one reader (p = .02) with poor inter-reader agreement (ICC 0.36). In utilizing ROC curves, thresholds of 107 mm (greatest axial AP dimension of hemoperitoneum) yielded a sensitivity and specificity of 0.81 and 0.62 for reader 1 and 0.69 and 0.55 for reader 2; 45 mm (posterior cul-de-sac AP dimension) yielded a sensitivity and specificity of 0.75 and 0.63 for reader 1 and 0.94 and 0.49 for reader 2; 70 mm (total cul-de-sac AP dimension) yielded a sensitivity and specificity of 0.75 and 0.64 for reader 1 and 0.75 and 0.50 for reader 2; and greater than 5 spaces yielded a sensitivity and specificity of 0.75 and 0.58 for reader 1 and 0.69 and 0.70 for reader 2. CONCLUSION: CT findings associated with intervention in hemoperitoneum due to ovarian cyst rupture include size of hemoperitoneum, number of abdominopelvic spaces with hemoperitoneum, and contrast extravasation.


Asunto(s)
Hemoperitoneo , Quistes Ováricos , Femenino , Hemoperitoneo/diagnóstico por imagen , Hemoperitoneo/etiología , Hemoperitoneo/terapia , Humanos , Quistes Ováricos/complicaciones , Quistes Ováricos/diagnóstico por imagen , Quistes Ováricos/terapia , Estudios Retrospectivos , Rotura Espontánea/complicaciones , Tomografía Computarizada por Rayos X/efectos adversos
8.
Radiographics ; 41(6): 1802-1818, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34559587

RESUMEN

Transarterial radioembolization (TARE) with yttrium 90 has increasingly been performed to treat hepatocellular carcinoma (HCC). TARE was historically used as a palliative lobar therapy for patients with advanced HCC beyond surgical options, ablation, or transarterial chemoembolization, but recent advancements have led to its application across the Barcelona Clinic Liver Cancer staging paradigm. Newer techniques, termed radiation lobectomy and radiation segmentectomy, are being performed before liver resection to facilitate hypertrophy of the future liver remnant, before liver transplant to bridge or downstage to transplant, or as a definite curative treatment. Imaging assessment of therapeutic response to TARE is challenging as the intent of TARE is to deliver local high-dose radiation to tumors through microembolic microspheres, preserving blood flow to promote radiation injury to the tumor. Because of the microembolic nature, early imaging assessment after TARE cannot rely solely on changes in size. Knowledge of the evolving methods of TARE along with the tools to assess posttreatment imaging and response is essential to optimize TARE as a therapeutic option for patients with HCC. ©RSNA, 2021.


Asunto(s)
Braquiterapia , Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/radioterapia , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Microesferas
9.
Am J Perinatol ; 37(6): 577-588, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-30978746

RESUMEN

The purpose of this review is to explain how diffusion-weighted imaging (DWI) is used during magnetic resonance imaging (MRI) exams in pregnant patients for specific maternal indications, including evaluation of acute pelvic pain, adnexal masses, cancer diagnosis and staging, and morbidly adherent placenta. While ultrasound is often the appropriate initial imaging for evaluating a pregnant patient, MRI can be helpful when a pelvic ultrasound is indeterminate. MRI has advantages in that it does not use ionizing radiation and has shown no known deleterious effects to the fetus. The use of gadolinium-based contrast is controversial during pregnancy. DWI is a functional sequence performed during an MRI exam, which is valuable in the absence of gadolinium contrast, and can increase the visibility of inflammation, abscesses, and tumors. Case examples will be presented to demonstrate the utility and added value of DWI over conventional anatomic T1- and T2-weighted imaging in diagnosis of maternal disease in the pregnant patient's pelvis.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Dolor Pélvico/diagnóstico por imagen , Pelvis/diagnóstico por imagen , Complicaciones del Embarazo/diagnóstico por imagen , Enfermedad Aguda , Apendicitis/diagnóstico por imagen , Enfermedad de Crohn/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Dolor Pélvico/etiología , Enfermedades Placentarias/diagnóstico por imagen , Embarazo , Enfermedades Uterinas/diagnóstico por imagen
10.
AJR Am J Roentgenol ; 210(2): W70-W79, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29355401

RESUMEN

OBJECTIVE: Differentiation of scrotal lesions is often dictated by whether they are intraor extratesticular. However, these regions are not entirely isolated, and disease processes can span both spaces. We review a variety of lesions that can involve both regions, describe the relevant anatomy, and illustrate their imaging appearances. CONCLUSION: Identification of involvement of both intra- and extratesticular regions by a single process can narrow the differential considerations and help arrive at the correct diagnosis.


Asunto(s)
Escroto/diagnóstico por imagen , Enfermedades Testiculares/diagnóstico por imagen , Ultrasonografía/métodos , Diagnóstico Diferencial , Progresión de la Enfermedad , Humanos , Masculino , Escroto/patología , Enfermedades Testiculares/patología
11.
AJR Am J Roentgenol ; 208(4): 721-732, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28140608

RESUMEN

OBJECTIVE: Rosai-Dorfman disease (RDD) is an uncommon benign histiocytic disorder. Extranodal involvement occurs in 43% and most commonly involves the head and neck, skin, and bones. We review less common imaging findings outside the head and neck. CONCLUSION: The imaging manifestations of RDD overlap with a variety of neoplastic and nonneoplastic conditions. Confirmation of an RDD diagnosis is based on specific histologic features. Radiologic assessment is used to rule out multifocality on initial workup and to evaluate treatment response.


Asunto(s)
Abdomen/diagnóstico por imagen , Diagnóstico por Imagen/métodos , Histiocitosis Sinusal/diagnóstico , Enfermedades Musculoesqueléticas/diagnóstico por imagen , Pelvis/diagnóstico por imagen , Enfermedades Torácicas/diagnóstico , Cabeza/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Cuello/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Rayos X/métodos
12.
Radiographics ; 37(7): 2026-2042, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29131770

RESUMEN

Characterization of renal tumors is critical to determine the best therapeutic approach and improve overall patient survival. Because of increased use of high-resolution cross-sectional imaging in clinical practice, renal masses are being discovered with increased frequency. As a result, accurate imaging characterization of these lesions is more important than ever. However, because of the wide array of imaging features encountered as well as overlapping characteristics, identifying reliable imaging criteria for differentiating malignant from benign renal masses remains a challenge. Multiparametric magnetic resonance (MR) imaging based on various anatomic and functional parameters has an important role and adds diagnostic value in detection and characterization of renal masses. MR imaging may allow distinction of benign solid renal masses from several renal cell carcinoma (RCC) subtypes, potentially suggest the histologic grade of a neoplasm, and play an important role in ensuring appropriate patient management to avoid unnecessary surgery or other interventions. It is also a useful noninvasive imaging tool for patients who undergo active surveillance of renal masses and for follow-up after treatment of a renal mass. The purpose of this article is to review the characteristic MR imaging features of RCC and common benign renal masses and propose a diagnostic imaging approach to evaluation of solid renal masses using multiparametric MR imaging. ©RSNA, 2017.


Asunto(s)
Adenoma Oxifílico/diagnóstico por imagen , Angiomiolipoma/diagnóstico por imagen , Carcinoma de Células Renales/diagnóstico por imagen , Neoplasias Renales/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Diagnóstico Diferencial , Humanos
13.
AJR Am J Roentgenol ; 206(2): 247-52, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26797350

RESUMEN

OBJECTIVE: This article reviews optimal treatment of allergic reactions to iodinated contrast material in pregnant patients. Initial evaluation and treatment of a pregnant patient is similar to that for a nonpregnant patient. However, additional steps, including assessment for uterine cramping, using left uterine displacement to improve venous return, and maintaining blood pressure to ensure placental perfusion, may be required. CONCLUSION: Adequate preparation and a team approach will provide optimal care for a pregnant patient who has an allergic reaction to a contrast agent.


Asunto(s)
Medios de Contraste/efectos adversos , Hipersensibilidad a las Drogas/terapia , Compuestos de Yodo/efectos adversos , Hipersensibilidad a las Drogas/diagnóstico , Femenino , Humanos , Embarazo , Factores de Riesgo , Tomografía Computarizada por Rayos X
14.
Radiographics ; 36(2): 414-32, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26849154

RESUMEN

Adrenal lesions are a common imaging finding. The vast majority of adrenal lesions are adenomas, which contain intracytoplasmic (microscopic) fat. It is important to distinguish between adenomas and malignant tumors, and chemical shift magnetic resonance (MR) imaging can be used to accomplish this distinction by depicting the fat in adenomas. Chemical shift imaging is based on the difference in precession frequencies of water and fat molecules, which causes them to be in different relative phases during the acquisition sequence and allows in-phase and opposed-phase images to be obtained. It is important to acquire these images by using the earliest possible echo times, with the opposed-phase echo before the in-phase echo, and by using a single breath hold to preserve diagnostic accuracy. Intracytoplasmic fat is depicted as signal drop on opposed-phase images when compared with in-phase images. Both qualitative and quantitative methods for assessing signal drop are detailed. The appearances of adrenal adenomas and other adrenal tumors on chemical shift MR images are described, and discriminatory ability at chemical shift MR imaging compared with that at adrenal computed tomography (CT) is explained. Other adrenal-related conditions in which chemical shift MR imaging is helpful are also discussed. Chemical shift MR imaging is a robust tool for evaluating adrenal lesions that are indeterminate at nonenhanced CT. However, it is important to know the advantages and disadvantages, including several potential imaging pitfalls. The characterization of adrenal lesions by using chemical shift MR imaging and adrenal CT should always occur in the appropriate clinical setting.


Asunto(s)
Adenoma/diagnóstico por imagen , Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Glándulas Suprarrenales/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tejido Adiposo/diagnóstico por imagen , Neoplasias de las Glándulas Suprarrenales/secundario , Tumor de Resto Suprarrenal/diagnóstico por imagen , Artefactos , Agua Corporal , Carcinoma/diagnóstico por imagen , Hemosiderosis/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Hallazgos Incidentales , Lipoma/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Primarias Múltiples/diagnóstico por imagen , Feocromocitoma/diagnóstico por imagen , Protones , Tomografía Computarizada por Rayos X
15.
AJR Am J Roentgenol ; 205(1): W32-41, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26102416

RESUMEN

OBJECTIVE: The 2012 revision of the Atlanta Classification emphasizes accurate characterization of collections that complicate acute pancreatitis: acute peripancreatic fluid collections, pseudocysts, acute necrotic collections, and walled-off necroses. As a result, the role of imaging in the management of acute pancreatitis has substantially increased. CONCLUSION: This article reviews the imaging findings associated with acute pancreatitis and its complications on cross-sectional imaging and discusses the role of imaging in light of this revision.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Pancreatitis/clasificación , Pancreatitis/diagnóstico , Tomografía Computarizada por Rayos X/métodos , Enfermedad Aguda , Medios de Contraste , Progresión de la Enfermedad , Humanos , Necrosis , Índice de Severidad de la Enfermedad
16.
AJR Am J Roentgenol ; 205(3): 685-92, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26295658

RESUMEN

OBJECTIVE: The objective of our study was to determine if placental MRI examinations performed for the detection of abnormal placentation earlier than 24 weeks' gestational age (GA) are more or less reliable than examinations performed at a later GA. MATERIALS AND METHODS: Two radiologists blinded to clinical, surgical, and pathologic reports retrospectively and independently reviewed 69 placental MRI examinations for nine imaging signs associated with abnormal placentation. A consensus of the suspicion of abnormal placentation (including accreta, increta, or percreta) was determined using a 5-point (low to high suspicion) Likert scale and compared with pathologic or surgical findings or both. RESULTS: Seventeen placental MRI examinations were performed at GA 14-23 weeks, and 52 placental MRI examinations were performed at GA 24-41 weeks. Reviewer agreement (Cronbach alpha) among the nine imaging signs was 0.86 (95% CI, 0.72-0.92) and 0.92 (95% CI, 0.92-0.94) for MRI examinations at GA 14-23 weeks and GA 24-41 weeks, respectively. Pathologic or surgical evidence of abnormal placentation was found in 41% and 65% of the cases between GA 14-23 weeks and GA 24-41 weeks, respectively. The AUC for the MRI-based consensus score and the presence of abnormal placentation for GA 14-23 weeks was 0.49 (95% CI, 0.21-0.78) compared with 0.92 (95% CI, 0.83-1.0) for GA 24-41 weeks (p = 0.002). CONCLUSION: Placental MRI examinations performed before 24 weeks' GA unreliably predict abnormal placentation.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Enfermedades Placentarias/diagnóstico , Adulto , Femenino , Edad Gestacional , Humanos , Enfermedades Placentarias/cirugía , Embarazo , Resultado del Embarazo , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Reproducibilidad de los Resultados , Estudios Retrospectivos
17.
Radiographics ; 35(7): 1922-39, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26473536

RESUMEN

Recent innovations in computed tomographic (CT) hardware and software have allowed implementation of low tube voltage imaging into everyday CT scanning protocols in adults. CT at a low tube voltage setting has many benefits, including (a) radiation dose reduction, which is crucial in young patients and those with chronic medical conditions undergoing serial CT examinations for disease management; and (b) higher contrast enhancement. For the latter, increased attenuation of iodinated contrast material improves the evaluation of hypervascular lesions, vascular structures, intestinal mucosa in patients with bowel disease, and CT urographic images. Additionally, the higher contrast enhancement may provide diagnostic images in patients with renal dysfunction receiving a reduced contrast material load and in patients with suboptimal peripheral intravenous access who require a lower contrast material injection rate. One limitation is that noisier images affect image quality at a low tube voltage setting. The development of denoising algorithms such as iterative reconstruction has made it possible to perform CT at a low tube voltage setting without compromising diagnostic confidence. Other potential pitfalls of low tube voltage CT include (a) photon starvation artifact in larger patients, (b) accentuation of streak artifacts, and (c) alteration of the CT attenuation value, which may affect evaluation of lesions on the basis of conventional enhancement thresholds. CT of the abdomen with a low tube voltage setting is an excellent radiation reduction technique when properly applied to imaging of select patients in the appropriate clinical setting.


Asunto(s)
Radiografía Abdominal/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Artefactos , Tamaño Corporal , Colonografía Tomográfica Computarizada , Medios de Contraste , Fenómenos Electromagnéticos , Humanos , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador/métodos , Selección de Paciente , Dosis de Radiación , Exposición a la Radiación , Radiografía Intervencional , Relación Señal-Ruido , Tomografía Computarizada por Rayos X/efectos adversos , Tomografía Computarizada por Rayos X/instrumentación , Urografía/métodos , Vísceras/diagnóstico por imagen
18.
Radiographics ; 35(1): 125-41, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25590393

RESUMEN

Cystic renal lesions are commonly encountered in abdominal imaging. Although most cystic renal lesions are benign simple cysts, complex renal cysts, infectious cystic renal disease, and multifocal cystic renal disease are also common phenomena. The Bosniak classification system provides a useful means of categorizing cystic renal lesions but places less emphasis on their underlying pathophysiology. Cystic renal diseases can be categorized as focal, multifocal, or infectious lesions. Diseases that manifest with focal lesions, such as cystic renal cell carcinoma, mixed epithelial and stromal tumor, and cystic nephroma, are often difficult to differentiate but have differing implications for follow-up after resection. Multifocal cystic renal lesions can be categorized as acquired or heritable. Acquired entities, such as glomerulocystic kidney disease, lithium-induced nephrotoxicity, acquired cystic kidney disease, multicystic dysplastic kidney, and localized cystic renal disease, often have distinct imaging and clinical features that allow definitive diagnosis. Heritable diseases, such as autosomal dominant polycystic kidney disease, von Hippel-Lindau disease, and tuberous sclerosis, are usually easily identified and have various implications for patient management. Infectious diseases have varied imaging appearances, and the possibility of infection must not be overlooked when assessing a cystic renal lesion. A thorough understanding of the spectrum of cystic renal disease will allow the radiologist to make a more specific diagnosis and provide the clinician with optimal recommendations for further diagnostic testing and follow-up imaging.


Asunto(s)
Enfermedades Renales Quísticas/diagnóstico , Neoplasias Renales/diagnóstico , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Diagnóstico Diferencial , Humanos , Enfermedades Renales Quísticas/clasificación , Enfermedades Renales Quísticas/diagnóstico por imagen , Neoplasias Renales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos
20.
Radiographics ; 34(3): 624-41, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24819785

RESUMEN

The ampulla of Vater is an important anatomic landmark where the common bile duct and main pancreatic duct converge in the major duodenal papilla. Imaging evaluation of the ampulla and periampullary region poses a unique diagnostic challenge to radiologists because of the region's complex and variable anatomy and the variety of lesions that can occur. Lesions intrinsic to the ampulla and involved segment of the biliary tree can be neoplastic, inflammatory, or congenital. Neoplastic lesions include ampullary adenocarcinomas and adenomas, which often are difficult to differentiate, as well as pancreatic or duodenal adenocarcinomas, pancreatic neuroendocrine tumors, and cholangiocarcinomas. Ultrasonography (US), computed tomography, magnetic resonance (MR) imaging, and MR cholangiopancreatography are commonly used to evaluate this region. Endoscopic retrograde cholangiopancreatography or endoscopic US examination may be necessary for more definitive evaluation. Periampullary conditions in the duodenum that may secondarily involve the ampulla include neoplasms, duodenitis, duodenal diverticula, and Brunner's gland hyperplasia or hamartomas. Because these lesions can exhibit a wide overlap of imaging features and subtle or nonspecific imaging findings, diagnosis is made on the basis of patient age, clinical history, and imaging and laboratory findings. Given the complexity of imaging evaluation of the ampulla and periampullary region, it is essential for radiologists to understand the variety of lesions that can occur and recognize their imaging characteristics.


Asunto(s)
Ampolla Hepatopancreática/patología , Neoplasias de los Conductos Biliares/diagnóstico , Enfermedades del Conducto Colédoco/diagnóstico , Diagnóstico por Imagen/métodos , Ampolla Hepatopancreática/diagnóstico por imagen , Colangiopancreatografia Retrógrada Endoscópica , Pancreatocolangiografía por Resonancia Magnética , Conducto Colédoco/diagnóstico por imagen , Conducto Colédoco/patología , Humanos , Perforación Intestinal/diagnóstico por imagen , Ultrasonografía
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