RESUMO
Helical CT evaluation of the abdomen and pelvis can be challenging in the cancer patient. This pictorial essay illustrates the important sites of neoplastic dissemination in the abdomen and pelvis. We will emphasize the classic CT appearance of several selected sites and indicate, where appropriate, the primary lesions usually associated with each.
Assuntos
Neoplasias Abdominais/diagnóstico por imagem , Neoplasias do Sistema Digestório/diagnóstico por imagem , Neoplasias das Glândulas Endócrinas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Diagnóstico Diferencial , Humanos , Invasividade Neoplásica/diagnóstico por imagem , Metástase Neoplásica/diagnóstico por imagem , Pelve/diagnóstico por imagemRESUMO
Spiral computed tomographic angiography (CTA) coupled with three-dimensional volume-rendering image processing is a less invasive alternative to conventional catheter angiography. The technique has been used successfully in a variety of vascular diseases. In this pictorial essay, we review the CTA findings in selected cases of vasculitis. Technical considerations and the potential clinical value of this method are discussed.
Assuntos
Angiografia/métodos , Tomografia Computadorizada por Raios X/métodos , Vasculite/diagnóstico por imagem , Adulto , Idoso , Feminino , Humanos , Masculino , Vasculite/patologiaRESUMO
Important sites of metastasis from intrathoracic and extrathoracic primary neoplasms are depicted on helical CT of the neck and thorax. This pictorial essay reviews several of these key sites of dissemination. For each, we illustrate the typical or classic appearance on helical CT and note the commonly associated primary malignancies.
Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/secundário , Neoplasias Torácicas/diagnóstico por imagem , Neoplasias Torácicas/secundário , Tomografia Computadorizada por Raios X , Humanos , Metástase Linfática , Tomografia Computadorizada por Raios X/métodosRESUMO
Spiral computed tomography (CT) is the state of the art today in imaging many features of the genitourinary tract. The use of dual-phase CT imaging improves our ability to detect and stage a wide range of pathologies. However, imaging in the arterial phase has several potential pitfalls that can result in either overcalling or undercalling genitourinary pathology. This paper reviews some of the common pitfalls and presents strategies on how to avoid them.
Assuntos
Tomografia Computadorizada por Raios X/métodos , Doenças Urológicas/diagnóstico por imagem , Doenças Uterinas/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , MasculinoRESUMO
Neurofibromatosis type 1 (NF1) is the most common of the phakomatoses and has a variety of localized or, more frequently, systemic manifestations throughout the thorax, abdomen, pelvis, and extremities. Classic computed tomographic (CT) findings in NF1 with thoracic involvement include small, well-defined subcutaneous neurofibromas, focal thoracic scoliosis, posterior vertebral scalloping, enlarged neural foramina, and characteristic rib abnormalities due to bone dysplasia or erosion from adjacent neurofibromas. However, more atypical manifestations are occasionally seen, and magnetic resonance (MR) imaging can be useful in equivocal cases. NF1 with abdominopelvic involvement tends to arise in the retroperitoneal, mesenteric, and paraspinal regions; it may be quite extensive and therefore difficult to distinguish from adenopathy at CT. The multiplanar capabilities of MR imaging, particularly with T2 weighting, make this modality helpful in evaluating affected patients and making the diagnosis. The classic peripheral manifestations of NF1 include limb hemihypertrophy, pseudarthrosis, peripheral nerve neurofibromas, and subcutaneous common and plexiform neurofibromas. In some cases of NF1, imaging findings are inconclusive, and biopsy and subsequent pathologic analysis are required. Familiarity with the various manifestations of NF1 in different anatomic locations is important in making the diagnosis and optimizing postdiagnostic treatment.
Assuntos
Neurofibromatose 1/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Neurofibromatose 1/patologiaRESUMO
The incidence of the interpretation of low-probability lung scans in asymptomatic patients with large central pulmonary embolisms and the prognostic implication of the ventilation-perfusion scan appearance in this clinical setting is not documented.
Assuntos
Pulmão/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Probabilidade , Embolia Pulmonar/epidemiologia , Cintilografia , Tomografia Computadorizada por Raios X , Relação Ventilação-Perfusão , Radioisótopos de XenônioRESUMO
Three-dimensional volume-rendered computed tomographic (CT) angiography represents an increasingly important clinical tool that, in many institutions, is replacing conventional angiography in the depiction of normal vascular anatomy and the diagnosis of vascular disorders. Evaluation of conditions affecting the renal vasculature constitutes a major focus of volume-rendered CT angiography, which has documented utility for demonstrating both arterial and venous disease. Arterial disorders include renal artery stenosis, renal artery aneurysms, and dissection. Venous disorders include splenorenal shunts, thrombosis, and intravascular tumor extension. In addition, volume-rendered CT angiography accurately displays the normal and variant renal vascular anatomy, which is crucial to detect before surgery, especially partial nephrectomy and laparoscopic nephrectomy. CT angiography is also useful in the evaluation of the renal vasculature following renal transplantation. Familiarity with proper CT protocols and data acquisition techniques are crucial for accurate diagnosis.
Assuntos
Angiografia , Imageamento Tridimensional , Artéria Renal/diagnóstico por imagem , Veias Renais/diagnóstico por imagem , Doenças Vasculares/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Sensibilidade e EspecificidadeRESUMO
Multidetector CT (MDCT) provides unparalleled capabilities for combining narrow scan collimation with rapid data acquisition protocols. When combined with CT angiographic techniques and 3D-volume rendering we are able to create unique displays for evaluating a range of clinical pathologies. In this pictorial review we present the potential advantages of using MDCT angiography for the evaluation of pancreatic cancer and its role in the accurate staging of these patients. The use of dual-phase CT scanning in both the arterial phase and portal phase is addressed with the role of 3D CT angiography clearly defined. Numerous case studies are presented to show the advantages of these techniques over simple axial CT imaging.
Assuntos
Angiografia/métodos , Carcinoma/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Angiografia/instrumentação , Artérias , Artéria Celíaca/diagnóstico por imagem , Apresentação de Dados , Feminino , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Veias Mesentéricas/diagnóstico por imagem , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pâncreas/irrigação sanguínea , Veia Porta/diagnóstico por imagem , Veia Esplênica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/instrumentação , Interface Usuário-ComputadorAssuntos
Hemangioendotelioma Epitelioide/diagnóstico por imagem , Hemangioendotelioma Epitelioide/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Pulmão/patologia , Tomografia Computadorizada por Raios X , Diagnóstico Diferencial , Feminino , Hemangioendotelioma Epitelioide/epidemiologia , Humanos , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Neoplasias Pulmonares/epidemiologia , Pessoa de Meia-IdadeRESUMO
Helical computed tomography (CT) allows rapid, cost-effective evaluation of patients with acute abdominal pain. Tailoring the examination to the working clinical diagnosis by optimizing constituent factors (eg, timing of acquisition, contrast material used, means and rate of contrast material administration, collimation, pitch) can markedly improve diagnostic accuracy. Rapid (>/=3 mL/sec) intravenous injection of contrast material is required for optimal assessment of acute pancreatitis, ischemic bowel, aortic aneurysm, and aortic dissection. Narrow collimation and small reconstruction intervals can help detect calculi in the biliary system and genitourinary tract. Tailored helical CT in patients with acute pyelonephritis usually involves several acquisitions through the kidneys during various phases of renal enhancement. In patients with suspected renal infarction, CT protocol must include an acquisition during the corticomedullary phase. Helical CT with 5-mm collimation through the lower abdomen and pelvis is used to evaluate patients with suspected diverticulitis. Use of both oral and intravenous contrast material can help localize small bowel perforation and characterize related complications. Tailored helical CT for assessment of abdominal hemorrhage consists of initial unenhanced CT followed by optional contrast material-enhanced CT. Clear communication between the radiologist, the patient, and the referring physician is essential for narrowing the differential diagnosis into a working diagnosis prior to helical CT.
Assuntos
Abdome Agudo/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Abdome Agudo/etiologia , Meios de Contraste , Diagnóstico Diferencial , Humanos , Aumento da Imagem , Sensibilidade e EspecificidadeAssuntos
Adenocarcinoma/complicações , Adenocarcinoma/secundário , Infecções por Clostridium/complicações , Abscesso Hepático/complicações , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/secundário , Pneumoperitônio/etiologia , Adenocarcinoma/diagnóstico por imagem , Idoso , Neoplasias do Colo/patologia , Humanos , Abscesso Hepático/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pneumoperitônio/diagnóstico por imagem , RadiografiaAssuntos
Artéria Hepática/diagnóstico por imagem , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/diagnóstico por imagemRESUMO
CT, especially helical CT, provides a fast and reliable modality for evaluation of the patient presenting with acute abdominal pain. Helical CT can provide an accurate diagnosis in the majority of patients and has found great utility in the evaluation of acute gastrointestinal emergencies, including acute appendicitis, diverticulitis, and small bowel obstruction. This article reviews proper helical CT technique, diagnostic imaging findings, and pitfalls of interpretation in evaluation of these acute abdominal disorders.
Assuntos
Abdome Agudo/diagnóstico por imagem , Abdome Agudo/etiologia , Apendicite/diagnóstico por imagem , Diverticulite/diagnóstico por imagem , Obstrução Intestinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Apendicite/complicações , Meios de Contraste , Diagnóstico Diferencial , Diverticulite/complicações , Humanos , Obstrução Intestinal/complicaçõesRESUMO
Renal lymphoma is most often seen in conjunction with multisystemic, disseminated lymphoma or as tumor recurrence. Renal lymphoma may also be seen in immunocompromised patients or, rarely, as primary disease. Computed tomography (CT) is the most sensitive, efficient, and comprehensive examination for evaluation of the kidneys in patients with suspected renal lymphoma. Helical CT in particular improves detection and characterization of lymphomatous renal involvement by optimizing contrast dynamics and data acquisition and is the current modality of choice for accurate staging of lymphoma. Typical CT patterns in renal lymphoma include single and multiple masses, invasion from contiguous retroperitoneal disease, perirenal disease, and diffuse renal infiltration. Atypical CT patterns may also be encountered and provide a diagnostic challenge. These include spontaneous hemorrhage, necrosis, heterogeneous attenuation, cystic transformation, and calcification. Solid renal masses including renal cell carcinoma and metastases are the most commonly encountered entities that mimic renal lymphoma at CT and require biopsy for definitive diagnosis. CT (particularly helical CT) is useful in the evaluation of patients with suspected renal lymphoma, and familiarity with the spectrum of findings in renal lymphoma is important for accurate diagnosis.
Assuntos
Neoplasias Renais/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Biópsia , Diagnóstico Diferencial , Humanos , Neoplasias Renais/patologia , Linfoma/patologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Reprodutibilidade dos TestesRESUMO
Computed tomography, magnetic resonance imaging, and transesophageal echocardiography represent the relatively noninvasive techniques available for imaging thoracic aortic disease, especially in the evaluation of aneurysms and dissections. The article discusses the technique and application of these modalities in the evaluation of thoracic aorta. Imaging appearances of the commonly encountered pathologies of the thoracic aorta are presented and discussed, and potential pitfalls of technique and diagnosis are addressed.
Assuntos
Aneurisma da Aorta Torácica/diagnóstico , Dissecção Aórtica/diagnóstico , Diagnóstico por Imagem , Aorta Torácica/patologia , Arteriosclerose/diagnóstico , Ecocardiografia Transesofagiana , Humanos , Imageamento por Ressonância Magnética , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios XRESUMO
Ovarian cancer is the second most common gynecologic malignancy in the United States and causes more deaths than any other cancer of the female reproductive system. Approximately two-thirds of patients have tumors that have spread beyond the pelvis at the time of diagnosis. Ovarian tumors arise from the surface epithelium or mesothelium, germ cells, or the gonadal stroma. Epithelial ovarian tumors include serous, mucinous, endometrioid, clear cell, and undifferentiated tumors. In general, the likelihood of malignancy increases with increasing solid-tissue elements and thicker septa. Surgery is central to the management of ovarian cancer. At the initial exploratory laparotomy, surgicopathologic staging and debulking of the tumor are undertaken. Patients with advanced cancer frequently undergo second-look surgery after chemotherapy to detect any residual disease. CT can provide staging information for preoperative planning and determination of surgical resectability, demonstrate tumor response to therapy, and allow detection of persistent or recurrent disease. However, a major limitation of CT is the lack of sensitivity for detection of small tumor implants, especially on the small intestine or mesentery. Dedicated CT of the pelvis is best performed with spiral CT. Ovarian carcinoma can spread by means of intraperitoneal implantation, lymphatic invasion, and hematogenous dissemination.
Assuntos
Carcinoma/diagnóstico por imagem , Neoplasias Ovarianas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adenocarcinoma de Células Claras/diagnóstico por imagem , Adenocarcinoma Mucinoso/diagnóstico por imagem , Carcinoma/secundário , Carcinoma Endometrioide/diagnóstico por imagem , Cistadenocarcinoma Seroso/diagnóstico por imagem , Feminino , Humanos , Pelve/diagnóstico por imagemRESUMO
Postpartum patients rarely develop complications that require radiologic evaluation. When indicated, CT can provide a rapid and reliable examination of the major pelvic organs and enable diagnosis of a multitude of postpartum complications, including abscesses, endometritis, thrombophlebitis, as well as more serious and potentially life-threatening sequelae of toxemia, DIC, and HELLP syndrome. This pictorial essay illustrates the utility of CT in the postpartum patient and demonstrates the spectrum of complications evaluated with CT.
Assuntos
Transtornos Puerperais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Abdome , Adulto , Feminino , Humanos , Pelve , GravidezRESUMO
OBJECTIVE: Accurate prenatal diagnosis of congenital diaphragmatic hernia is important for perinatal planning and potential fetal surgery. We describe the application and usefulness of helical CT amniography in the evaluation of suspected congenital diaphragmatic hernia in three fetuses. CONCLUSION: Helical CT amniography is an efficient means for evaluation of congenital diaphragmatic hernia. Accurate diagnosis was made in all three patients.