Computed tomography (CT), magnetic resonance imaging (MRI), and adrenal vein sampling (AVS) are used to distinguish unilateral from bilateral aldosterone secretion so that primary aldosteronism can...

Systematic Review: Diagnostic Procedures to Differentiate Unilateral From Bilateral Adrenal Abnormality in Primary Aldosteronism

Fibromuscular dysplasia (FMD) is nonatherosclerotic, noninflammatory vascular disease that may result in arterial stenosis, occlusion, aneurysm, or dissection.1–3 The cause of FMD and its prevalence in the general population are not known.4 FMD has been reported in virtually every arterial bed but most commonly affects the renal and extracranial carotid and vertebral arteries (in ≈65% of cases).5 The clinical manifestations of FMD are determined primarily by the vessels that are involved. When the renal artery is involved, the most frequent finding is hypertension, whereas carotid or vertebral artery FMD may lead to dizziness, pulsatile tinnitus, transient ischemic attack (TIA), or stroke. There is an average delay from the time of the first symptom or sign to diagnosis of FMD of 4 to 9 years.5,6 This is likely because of a multitude of factors: the perception that this is a rare disease and thus FMD is not considered in the differential diagnosis, the reality that FMD is poorly understood by many healthcare providers, and the fact that many of the signs and symptoms of FMD are nonspecific, thus leading the clinician down the wrong diagnostic pathway. A delay in diagnosis can lead to impaired quality of life and poor outcomes such as poorly controlled hypertension and its sequelae, TIA, stroke, dissection, or aneurysm rupture. It should also be noted that FMD may be discovered incidentally while imaging is performed for other reasons or when a bruit is heard in the neck or abdomen in an asymptomatic patient without the classic risk factors for atherosclerosis.

The first description of FMD is attributed to Leadbetter and Burkland7 in a 5½-year-old boy with severe hypertension and a renal artery partially occluded by an intra-arterial mass of smooth muscle. He underwent a unilateral nephrectomy of an …

Fibromuscular Dysplasia: State of the Science and Critical Unanswered Questions A Scientific Statement From the American Heart Association

PURPOSE: To retrospectively evaluate the effectiveness of radiofrequency (RF) ablation of hepatocellular carcinoma (HCC) by using histologic examination of the explanted liver. MATERIALS AND METHODS: The study was approved by the medical center Institutional Review Board, with waiver of informed consent. Forty-seven HCC nodules in 24 patients (18 men, six women; age range, 33–71 years; mean age, 56 years) were treated with single or double RF ablation sessions prior to liver transplantation. Histologic data from hematoxylin-eosin staining of explanted liver specimens were retrospectively reviewed to determine treatment success, which was defined as the absence of residual or recurrent viable carcinoma cells at treatment site. Tumor size and the presence of large (≥3 mm) abutting vessels that were observed during imaging were tested as potential predictors of treatment success or failure (Fisher exact test). In patients who underwent postablation computed tomographic (CT) or magnetic resonance (MR) imaging...

Radiofrequency ablation of hepatocellular carcinoma: treatment success as defined by histologic examination of the explanted liver.

"Vulnerable" plaques are atherosclerotic plaques that have a high likelihood to cause thrombotic complications, such as myocardial infarction or stroke. Plaques that tend to progress rapidly are also considered to be vulnerable. Besides luminal stenosis, plaque composition and morphology are key determinants of the likelihood that a plaque will cause cardiovascular events. Noninvasive magnetic resonance (MR) imaging has great potential to enable characterization of atherosclerotic plaque composition and morphology and thus to help assess plaque vulnerability. A classification for clinical, as well as pathologic, evaluation of vulnerable plaques was recently put forward in which five major and five minor criteria to define vulnerable plaques were proposed. The purpose of this review is to summarize the status of MR imaging with regard to depiction of the criteria that define vulnerable plaques by using existing MR techniques. The use of MR imaging in animal models and in human disease in various vascular beds, particularly the carotid arteries, is presented.

The Vulnerable, or High-Risk, Atherosclerotic Plaque: Noninvasive MR Imaging for Characterization and Assessment

Several advances in diagnosis, treatment and palliation of cholangiocarcinoma (CC) have occurred in the last decades. A multidisciplinary approach to this disease is therefore recommended. CC is a relatively rare tumor and the main risk factors are: chronic inflammation, genetic predisposition and congenital abnormalities of the biliary tree. While the incidence of intra-hepatic CC is increasing, the incidence of extra-hepatic CC is trending down. The only curative treatment for CC is surgical resection with negative margins. Liver transplantation has been proposed only for selected patients with hilar CC that cannot be resected who have no metastatic disease after a period of neoadjuvant chemo-radiation therapy. Magnetic resonance imaging/magnetic resonance cholangiopancreatography, positron emission tomography scan, endoscopic ultrasound and computed tomography scans are the most frequently used modalities for diagnosis and tumor staging. Adjuvant therapy, palliative chemotherapy and radiotherapy have been relatively ineffective for inoperable CC. For most of these patients biliary stenting provides effective palliation. Photodynamic therapy is an emerging palliative treatment that seems to provide pain relief, improve biliary patency and increase survival. The clinical utility of other emerging therapies such as transarterial chemoembolization, hepatic arterial chemoinfusion and high intensity intraductal ultrasound needs further study.

Advances in diagnosis, treatment and palliation of cholangiocarcinoma: 1990-2009.

Accuracy in quantifying arterial occlusive disease requires an understanding of the relevant technical considerations and familiarity with the strengths and weaknesses of various imaging modalities in this setting. The degree of stenosis is evaluated in terms of diameter stenosis, which can be measured on either projection images or cross-sectional images, or area stenosis, which can be measured only on cross-sectional images. With projection images, the minimum luminal diameter should be sought on multiple images obtained at different angles. The reference site used for measurement should be noted and may be located at the level of the lesion or in a normal-looking portion of the stenotic vessel near the lesion. Multi– detector row computed tomographic (CT) angiography and magnetic resonance (MR) angiography are starting to replace digital subtraction angiography in quantifying arterial occlusive disease. CT angiography allows accurate evaluation without reducing in-plane resolution, although beam-hardening artifacts from high-attenuation structures can degrade image quality. MR angiography is useful even in cases of severe calcification but has a lower spatial resolution. Ultrasonography (US) may also be helpful in quantifying arterial occlusive disease; US analysis is almost always based on blood flow velocity measurement. Precise measurements of stenotic occlusion will help determine optimal therapy for affected patients. © RSNA, 2005

https://pubs.rsna.org/doi/pdf/10.1148/rg.255055014

Quantitative Vascular Measurements in Arterial Occlusive Disease

The histopathologic features and classification of ductal carcinoma in situ are reviewed and correlated with radiologic findings, with an emphasis on magnetic resonance imaging features.

Radiologic-Pathologic Correlation of Ductal Carcinoma in Situ

OBJECTIVE. We reviewed the CT findings of the subtypes of papillary renal cell carcinoma (RCC), which behave differently clinicopathologically.CONCLUSION. The CT features of the two pathologic subtypes of papillary RCC differ, probably reflecting their different pathologic features. Type 1 tumors have more distinct margins than type 2 tumors and have homogeneous density. Although type 2 tumors in the early stages show findings similar to those of type 1 tumors, they are at more advanced stages on the whole, with CT features showing indistinct margins, frequent centripetal infiltration, and tumor thrombi in all pT3b cases. Radiologists should be familiar with the CT features of papillary RCC that suggest different pathologic behaviors, such as tumor stage, tumor proliferation, and microvascular or vascular invasion.

Differentiation of pathologic subtypes of papillary renal cell carcinoma on CT.

Objective
Positron emission tomography (PET) with fluorodeoxyglucose (FDG) is widely used for evaluation of cancer and ischemic heart disease Recently, increased myocardial FDG uptake has been reported to be related to some types of heart disease, such as sarcoidosis However, the physiological increased FDG uptake in the heart often mimics the abnormal high uptake in these cases In this study, we investigated the relationships between myocardial uptake and age, blood glucose level, fasting period, and hospitalization status (inpatient vs outpatient)

Evaluation of the relationship between physiological FDG uptake in the heart and age, blood glucose level, fasting period, and hospitalization.

We present two cases of adrenal hemangioma, a rare non-functioning adrenal tumor, and correlate the CT and MR imaging findings with the pathological findings. Peripheral spotty contrast enhancement with centripetal enhancement was noted in one case. This pattern of enhancement is crucial for diagnosing adrenal hemangioma. The other case showed only thin rim enhancement without centripetal enhancement. This finding can be seen in other adrenal tumors, making diagnosis difficult. Marked hyperintensity on T2-weighted images and focal hyperintensity on T1-weighted images that showed focal hemorrhage and calcification were noted. These findings can also be seen in other adrenal tumors and are not pathognomonic of adrenal hemangioma. However, observing the combination of these findings can lead to the correct diagnosis.

Takayuki Yamada

Papers

Quantitative Vascular Measurements in Arterial Occlusive Disease

Radiologic-Pathologic Correlation of Ductal Carcinoma in Situ

Differentiation of pathologic subtypes of papillary renal cell carcinoma on CT.

Evaluation of the relationship between physiological FDG uptake in the heart and age, blood glucose level, fasting period, and hospitalization.

Two cases of adrenal hemangioma: CT and MRI findings with pathological correlations.