Intracranial abscesses are life-threatening medical emergencies with pyogenic debris accumulating in the brain. Delay in the diagnosis can result in significant morbidity and mortality. Computed tomography and magnetic resonance imaging play an important role in the diagnosis of brain abscesses. However, the classic ring-enhancing appearance of an intracranial abscess can be mimicked by several other entities, most notably a necrotic tumor. This paper reviews new advances in CT and MR for imaging patients with suspected brain abscess. The role of computed tomography (CT) perfusion and new magnetic resonance sequences including DWI sequences, ADC map, MR spectroscopy, FLAIR and post-contrast enhanced T1 weighted images will also be discussed.
The treatment of aortic abdominal aneurysms with endovascular repair provides a treatment alternative for high-risk surgical candidates. Computed Tomographic Angiography (CTA) has become the preferred imaging modality for preoperative evaluation of abdominal aortic aneurysms, postoperative assessment of endovascular repair and complications, and long term surveillance. Accurate evaluation of these devices and identification of endoleaks and other complications by the radiologist is critical to assuring successful outcomes.
Extra-pulmonary thoracic aspergilloma is an unusual pathologic manifestation of this organism. We present a case manifesting as a mediastinal mass on chest CT causing some diagnostic difficulty and requiring surgical resection.
Significant advances in computed tomography (CT) scanner technology as well as 3D imaging software and hardware have resulted in amazing improvements in CT imaging of blood vessels. CT angiography has now been incorporated into daily practice and in may cases has replaced conventional angiography. CT angiography has also resulted in new applications for CT such as coronary angiography. This article discusses the current state of the art of 3D CT angiography and reviews the literature. Extensive case examples are included.
Computed Tomography (CT) is useful for evaluation of both benign and malignant pathology involving the duodenum. CT can detect and stage duodenal malignancies as well as detect inflammatory conditions such as duodenitis. Careful CT technique is necessary to optimize detection of abnormalities. This includes the use of oral contrast, preferably water, as well as IV contrast. 3D imaging can improve disease detection and help with surgical planning. This article reviews the current role of CT in duodenal imaging, describes appropriate CT protocols and illustrates a wide variety of duodenal pathology.
Intracranial epidermoid tumors or cysts are considered benign lesions. Differentiation of epidermoid tumors from arachnoid cysts is important for appropriate patient care because the treatment is different for each lesion. Arachnoid cysts can appear very similar to epidermoid tumors on computed tomography (CT). Epidermoid tumors can grow in the cerebellopontine angle (CPA) cistern, the most common location of these lesions, resulting in trigeminal neuralgia and facial paralysis. Treatment for epidermoid tumors is exclusively surgery. Arachnoid cyst, on the other hand, is a benign condition that rarely produces symptoms. Recent advances in magnetic resonance imaging (MRI) have allowed more accurate imaging diagnosis of epidermoid tumors. This article reviews the recent advances in MRI using conventional T1W, post-contrast T1W, T2W, steady-state free precession imaging, fluid-attenuated inversion recovery (FLAIR), diffusion-weighted imaging (DWI), and proton magnetic resonance spectroscopy (MRS) in the imaging diagnosis of epidermoid tumors.
Enteric duplication cysts are rare congenital anomalies of the GI tract. We present a most unusual case presenting as a cystic lesion on the pancreas simulating a cystic pancreatic neoplasm. The differential diagnosis of cystic pancreatic lesions as well as duplication cysts is discussed.
OBJECTIVE:To determine the computed tomography (CT) evolution of various pulmonary manifestations of Wegener's Granulomatosis (WG) following appropriate pharmacologic treatment of the disease.METHODS:Eleven patients with WG were identified, each of whom had had at least two CT examinations. CTs were reviewed retrospectively to identify pulmonary lesions of WG. Lesions were categorized as nodules, cavities, lobar atelectasis, pulmonary bands, or infiltrates. To determine the evolution of each individual lesion following pharmacologic treatment, the authors compared the lesions at presentation to their appearances on follow-up CT examinations.RESULTS:A total of 112 lesions were identified (nodules = 70, cavities = 25, lobar atelectasis = 7, pulmonary bands = 6, infiltrates = 4). The mean time interval between CT examinations was 34 weeks (range: 3-248 weeks). Treated nodules tended to become smaller (33/70, 47%), to resolve (14/70, 20%), or to remain unchanged (8/70, 11%). However, the nodules became larger or cavitated in a substantial minority of cases (13/70, 19% and 2/70, 3%, respectively). Although more than half of the treated cavities became smaller (13/25, 52%) or resolved (1/25, 4%), many evolved into nodules (6/25, 24%) or enlarged (5/25, 20%). All cases of lobar atelectasis (14/14, 100%) and transpulmonary bands (6/6, 100%) were unchanged at follow-up. All infiltrates were either resolved (3/4, 75%) or substantially improved (1/4, 25%).CONCLUSION:WG has a wide spectrum of pulmonary manifestations. Nodules, cavities, and infiltrates are among the most common lesions seen on CT. Although these findings tend to improve with treatment, mixed responses are not uncommon. Lobar atelectasis and transpulmonary bands tend not to improve, even with the occurrence of clinical disease remission.
Primary retroperitoneal neoplasms account for only 0.1-0.2% of all malignancies. Retroperitoneal neoplasms are most commonly mesodermal, neurogenic or lymphatic in origin, with lymphoma, liposarcoma, leiomyosarcoma and malignant fibrous histiocytoma the vast majority of malignant primary retroperitoneal tumors. Although the radiographic features of retroperitoneal neoplasms often overlap, certain CT characteristics, pattern of spread and specific tumor prevalence among different demographic groups can help suggest the tumor type. CT is used to diagnosis and assess the size and extent of retroperitoneal tumors, as well as assess the involvement of organs and vasculature with resection in mind.
Traumatic bowel and mesenteric injuries are notoriously difficult to diagnose. CT has become the modality of choice for evaluating stable trauma patients for the presence of intra-abdominal injury. This article will summarize the CT findings useful for detecting bowel and mesenteric injury.
Epitheloid hepatic hemangioendothelioma was defined as a specific entity by Weiss and Enzinger in 1982. Histologically, this tumor originates from vascular endothelial cells and spindle cells. We report 3 cases of this rare neoplasm that presented to our institution over the past 3 years and briefly review the pathologic and imaging findings on MDCT (multiphase detector computed tomography).
By definition pulmonary edema is an abnormal accumulation of water in the lung. Consequently, the computed tomography (CT) appearance of pulmonary edema reflects the sequence of this accumulation. In early hydrostatic pulmonary edema, CT shows vascular engorgement and peribronchovascular cuffing that increases with the severity of edema and that is associate in late stage, with consolidations. In acute respiratory distress syndrome (ARDS), CT shows the proportion of injured parenchyma and depicts associated alterations as parenchymal infiltrate and consolidation, pleural effusion, pneumothorax. These merely morphological findings can be complemented with data from objective CT analysis of the lung parenchyma. Indeed CT can assess lung water noninvasively. Correlated with hydrodynamic parameter, these objective measurements show that the increase of lung density parallels parenchymal fluid overload. These data also show that the occurrence of ground glass opacities can precede the hemodynamic evidence of edema.
The complex ball and socket hip joint requires multiple projections for complete assessment. Though these have traditionally been acquired using multiple plain films, appropriately post-processed helical CT data can provide a comprehensive evaluation of congenital and acquired hip conditions from a single study.
Rheumatoid arthritis (RA) is a systemic disease manifest as a symmetric polyarthritis usually in the setting of elevated autoantibodies (rheumatoid factor). This disease affects 1-2% of the world's population, most frequently in the 25-55 year old age group and has a female predominance (2.5:1). Nearly 50% of patients with RA demonstrate some type of extra-articular manifestation of the disease such as pleuritis, pleuropericarditis, vasculitis, pneumonitis, pulmonary fibrosis, scleritis or nodulosis. Pulmonary involvement in RA is common and can be due to the disease itself as well as to the therapies used to treat it. In fact, lung disease is the second most common cause of death, following infection, for patients with RA and has been reported to effect between 1-40% of patients. RA associated interstitial lung disease (ILD) is often subtle in onset, slowly progressive and of unclear etiology and response to treatment. This article aims to clarify the current clinical, radiographic and pathologic status of RA-ILD.
Primary pulmonary arterial hypertension is a rare lethal disease that typically presents radiographically with enlarged central pulmonary arteries, pruning of the peripheral vasculature, and cardiomegaly but clear lung fields. Although it is a disease of unknown etiology, primary PAH has been associated with anorexigen use. We present a case of pulmonary arterial hypertension in a woman with a history of fenfluramine and phentermine use who presented with diffuse micronodules on computed tomography scan. Lung biopsy confirmed the micronodules were radiographic manifestations of extensive diffuse plexogenic arterial lesions. This report represents an unusual radiographic presentation of anorexigen related pulmonary arterial hypertension, and to our knowledge, the first case reported as presenting with diffuse micronodules on high resolution computed tomography scan.
(2004). How We Do It: CT of the Spleen. Critical Reviews in Computed Tomography: Vol. 45, No. 1, pp. 1-9.
(2003). Radiation Issues with Multidetector Row Helical CT. Critical Reviews in Computed Tomography: Vol. 44, No. 2, pp. 95-117.
