Malak Itani

Multimodality approach for imaging of non-traumatic acute abdominal emergencies

Abstract“Acute abdomen” includes spectrum of medical and surgical conditions ranging from a less severe to life-threatening conditions in a patient presenting with severe abdominal pain that develops over a period of hours. Accurate and rapid diagnosis of these conditions helps in reducing related complications. Clinical assessment is often difficult due to availability of over-the-counter analgesics, leading to less specific physical findings. The key clinical decision is to determine whether surgical intervention is required. Laboratory and conventional radiographic findings are often non-specific. Thus, cross-sectional imaging plays a pivotal role for helping direct management of acute abdomen. Computed tomography is the primary imaging modality used for these cases due to fast image acquisition, although US is more specific for conditions such as acute cholecystitis. Magnetic resonance imaging or ultrasound is very helpful in patients who are particularly sensitive to radiation exposure, such as pregnant women and pediatric patients. In addition, MRI is an excellent problem-solving modality in certain conditions such as assessment for choledocholithiasis in patients with right upper quadrant pain. In this review, we discuss a multimodality approach for the usual causes of non-traumatic acute abdomen including acute appendicitis, diverticulitis, cholecystitis, and small bowel obstruction. A brief review of other relatively less frequent but important causes of acute abdomen, such as perforated viscus and bowel ischemia, is also included.

MRI of female urethra and periurethral pathologies

Introduction and hypothesisAccurate diagnosis of a wide spectrum of urethral/periurethral pathologies in women remains challenging due to its anatomical location and nonspecific clinical presentations. Magnetic resonance imaging (MRI) has emerged as the modality of choice for diagnosing female urethral and periurethral pathologies due to its multiplanar scanning capability, superior soft tissue differentiation, noninvasive nature, and overall excellent contrast resolution.MethodsIn this narrative review, we describe the use of MRI to visualize the female urethra and periurethral pathologies.ResultsMRI can confidently characterize lesions into cystic or solid, provide a more succinct differential diagnosis, and in some cases provide a specific and accurate diagnosis, enabling surgeons to prepare a roadmap before operative procedure. Moreover, functional MRI can be useful to assess dynamic disorders such as urethral hypermobility.ConclusionsWe provide a comprehensive review of normal MR anatomy of the female urethra, as well as the MR features of practically important urethral and periurethral lesions.

Calciphylaxis on bone scan: correlation between molecular and cross-sectional findings

Calciphylaxis is a rare devastating medical condition commonly associated with end-stage renal disease and characterized by extensive microvascular calcifications. We describe a case of calciphylaxis presenting on Tc-99m MDP bone scan imaging with asymmetric radiotracer uptake within the lower extremities corresponding to extensive soft tissue calcifications on Computed tomography. Familiarity with the classic clinical presentation and imaging features of this rare entity may help its early identification and treatment.

Deep Vein Thrombosis Presenting on Pulmonary Ventilation and Perfusion Scintigraphy.

A 52-year-old woman presenting with dyspnea was referred for a ventilation and perfusion scan (VQ). VQ images (with Tc-DTPA [diethylene triamine pentaacetic acid aerosol] and Tc-MAA [macroaggregated albumin]) initially appeared normal; however, count rates on perfusion images were similar to ventilation images, implying little Tc-MAA had reached the lungs. Spot images of the injected extremity demonstrated focal Tc-MAA accumulation worrisome for a venous thrombus, subsequently confirmed by Doppler ultrasound. Careful attention to relative radiotracer count rates on VQ scans is crucial to ensure diagnostic utility. In addition, abnormal low perfusion radiotracer counts may unveil other pathology with important clinical implications.

PET/CT in the Diagnosis and Workup of Sarcoidosis: Focus on Atypical Manifestations

Sarcoidosis is a multisystem disease characterized by the formation of noncaseating granulomas. Lung and intrathoracic lymph nodes are classic sites of involvement; however, sarcoidosis can affect any site in the body. The clinical course is extremely variable, and the imaging features are diverse and dependent on the affected site, degree of inflammation, and treatment the patient receives. Atypical manifestations and imaging findings can make diagnosis and/or management challenging. In addition, assessment of treatment response can be difficult in the setting of chronic disease. Fluorine 18 fluorodeoxyglucose (FDG) PET/CT is sensitive for assessment of the inflammatory activity of sarcoidosis in any organ. Although FDG PET/CT is not included in the standard workup for sarcoidosis, there has been growing evidence that supports the value of this examination in guiding diagnosis and management. FDG PET/CT may be especially useful for assessing reversible granuloma, treatment response, disease extent, occult disease, and cardiac or osseous sarcoidosis, and determining the most suitable biopsy site. Capability to image the entire body during a single examination is advantageous in cases of systemic disease such as sarcoidosis. The authors review the use of FDG PET/CT, providing up-to-date evidence and describing various cases of sarcoidosis in which FDG PET/CT has an important role in diagnosis and/or management. They also discuss the usefulness of FDG PET/CT in cases of selective manifestations of sarcoidosis. ©RSNA, 2018.

Fetal Urinary Tract Anomalies: Review of Pathophysiology, Imaging, and Management

OBJECTIVE Common fetal anomalies of the kidneys and urinary tract encompass a complex spectrum of abnormalities that can be detected prenatally by ultrasound. Common fetal anomalies of the kidneys and urinary tract can affect amniotic fluid volume production with the development of oligohydramnios or anhydramnios, resulting in fetal pulmonary hypoplasia and, potentially, abnormal development of other fetal structures. CONCLUSION We provide an overview of common fetal anomalies of the kidneys and urinary tract with an emphasis on sonographic patterns as well as pathologic and postnatal correlation, along with brief recommendations for postnatal management. Of note, we render an updated classification of fetal abnormalities of the kidneys and urinary tract based on the presence or absence of associated urinary tract dilation. In addition, we review the 2014 classification of urinary tract dilation based on the Linthicum multidisciplinary consensus panel.

Physical Chemistry of Bile: Detailed Pathogenesis of Cholelithiasis

Abstract Despite the overwhelming prevalence of cholelithiasis, many health care professionals are not familiar with the basic pathophysiology of gallstone formation. This article provides an overview of the biochemical pathways related to bile, with a focus on the physical chemistry of bile. We describe the important factors in bile synthesis and secretion that affect the composition of bile and consequently its liquid state. Within this biochemical background lies the foundation for understanding the clinical and sonographic manifestation of cholelithiasis, including the pathophysiology of cholesterol crystallization, gallbladder sludge, and gallstones. There is a brief discussion of the clinical manifestations of inflammatory and obstructive cholestasis and the impact on bile metabolism and subsequently on liver function tests. Despite being the key modality in diagnosing cholelithiasis, ultrasound has a limited role in the characterization of stone composition.

The Role of Pulmonary Scintigraphy in the Evaluation of Adults with Congenital Heart Disease

Adults with congenital heart disease represent a growing population with challenging and complex medical management. Pulmonary scintigraphy can play a valuable role in the evaluation and care of this patient population. We present a review of the variety of clinical scenarios where pulmonary scintigraphy can be helpful in the evaluation of adults with congenital heart disease, along with technical considerations associated with these studies.

Lacrimal gland uptake on F-18 florbetapir amyloid positron emission tomography scan

In 2012, the Food and Drug Administration (FDA) approved the use of F-18 florbetapir to estimate β-amyloid neuritic plaque density when indicated. A normal scan will show increased radiotracer uptake in the white matter. Mild uptake in salivary glands, skin, muscles, and bones is considered normal. Being a new and infrequently performed study, familiarity with normal biodistribution and variants is important. We hereby present 2 cases with F-18 florbetapir uptake in lacrimal glands. Patients had no symptoms or known systemic conditions to explain this uptake. We speculate that lacrimal gland uptake of F-18 florbetapir could represent a normal variant.

I-131 uptake in fat necrosis of the breast

I-131 uptake in the breast has been described with a variety of normal and pathologic conditions. We present the case of a 38-year-old female who received 317 millicuries of radioactive I-131 treatment for papillary thyroid carcinoma. Post-treatment scan demonstrated I-131 uptake in an area of fat necrosis in the breast.