Practical Overview of 123I-Ioflupane Imaging in Parkinsonian Syndromes.

Parkinsonian syndromes are a heterogeneous group of progressive neurodegenerative disorders involving the nigrostriatal dopaminergic pathway and are characterized by a wide spectrum of motor and nonmotor symptoms. These syndromes are quite common and can profoundly impact the lives of patients and their families. In addition to classic Parkinson disease, parkinsonian syndromes include multiple additional disorders known collectively as Parkinson-plus syndromes or atypical parkinsonism. These are characterized by the classic parkinsonian motor symptoms with additional distinguishing clinical features. Dopamine transporter SPECT has been developed as a diagnostic tool to assess the levels of dopamine transporters in the striatum. This imaging assessment, which uses iodine 123 (123I) ioflupane, can be useful to differentiate parkinsonian syndromes caused by nigrostriatal degeneration from other clinical mimics such as essential tremor or psychogenic tremor. Dopamine transporter imaging plays a crucial role in diagnosing parkinsonian syndromes, particularly in patients who do not clearly fulfill the clinical criteria for diagnosis. Diagnostic clarification can allow early treatment in appropriate patients and avoid misdiagnosis. At present, only the qualitative interpretation of dopamine transporter SPECT is approved by the U.S. Food and Drug Administration, but quantitative interpretation is often used to supplement qualitative interpretation. The authors provide an overview of patient preparation, common imaging findings, and potential pitfalls that radiologists and nuclear medicine physicians should know when performing and interpreting dopamine transporter examinations. Alternatives to 123I-ioflupane imaging for the evaluation of nigrostriatal degeneration are also briefly discussed. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Intenzo and Colarossi in this issue.

Imaging evaluation of lymphoma in pregnancy with review of clinical assessment and treatment options.

Lymphoma-related malignancies can be categorized as Hodgkin's lymphoma (HL) or non-Hodgkin's lymphoma (NHL) based on histologic characteristics. Although quite rare during pregnancy, HL and NHL are the fourth and fifth most common malignancies during the pregnancy period, respectively. Given the rarity of lymphoma among pregnant patients, radiologists are usually unfamiliar with the modifications required for staging and treatment of this population, even those who work at centers with busy obstetrical services. Therefore, this manuscript serves to not only review the abdominopelvic imaging features of lymphoma in pregnancy, but it also discusses topics including birthing parent and fetal lymphoma-related prognosis, both antenatal and postpartum, current concepts in the management of pregnancy-related lymphoma, as well as the current considerations regarding birthing parent onco-fertility.

Altered Biodistribution on 99m Tc-Dimercaptosuccinic Acid Renal Scan.

ABSTRACT: 99m Tc-dimercaptosuccinic acid ( 99m Tc-DMSA) scans are used to evaluate renal cortical defects typically related to parenchymal scarring or pyelonephritis, and ectopic renal parenchyma. 99m Tc-DMSA binds to metalloproteins in proximal tubular cells and typically localizes to the renal cortex, with minimal excretion. Planar and SPECT images are obtained 2 to 4 hours after IV administration of 99m Tc-DMSA. Altered 99m Tc-DMSA biodistribution has been reported in various conditions, including renal injury, technical issues, infiltrative processes, and hematologic disorders. Here, we present a case of altered biodistribution, with hepatic and splenic radiotracer uptake in the setting of hepatosplenomegaly and hematologic abnormalities concerning for a systemic hematologic disorder/lymphohistiocytosis.

MR Defecating Proctography with Emphasis on Posterior Compartment Disorders.

MR defecating proctography (MRDP) is a noninvasive examination that can be used for evaluating posterior compartment disorders. MRDP has several advantages over conventional fluoroscopic defecography. These benefits include high-contrast resolution evaluation of the deep pelvic organs, simultaneous multicompartmental assessment that is performed statically and dynamically during defecation, and lack of ionizing radiation. MRDP also provides a highly detailed anatomic evaluation of the pelvic floor supportive structures, including direct assessment of the pelvic floor musculature and indirect assessment of the endopelvic fascia. As the breadth of knowledge regarding anatomic and functional posterior compartment disorders expands, so too does the advancement of noninvasive and surgical treatment options for these conditions. High-quality MRDP examinations, with key anatomic and functional features reported, guide treatment planning. Reporting of MRDP examination findings with use of standardized terminology that emphasizes objective measurements rather than subjective grading aids consistent communication among radiologists, clinicians, and surgeons. Familiarity with commonly encountered posterior compartment pelvic floor pathologic entities that contribute to posterior compartment disorders and awareness of the essential information needed by surgeons are key to providing an optimal multidisciplinary discussion for planning pelvic floor dysfunction treatment. The authors provide an overview of the basic concepts of the MRDP acquisition technique, the anatomic abnormalities of posterior compartment pelvic floor pathologic entities associated with defecatory disorders, and recently developed interdisciplinary MRDP reporting templates and lexicons. In addition, the associated imaging findings that are key for surgical treatment guidance are highlighted. © RSNA, 2022 Online supplemental material is available for this article.

Pitfalls in the interpretation of pediatric head CTs: what the emergency radiologist needs to know.

Pediatric radiology studies can be some of the most anxiety-inducing imaging examinations encountered in practice. This can be in part due to the wide range of normal anatomic appearances inherent to the pediatric population that create potential interpretive pitfalls for radiologists. The pediatric head is no exception; for instance, the inherent greater water content within the neonatal brain compared to older patients could easily be mistaken for cerebral edema, and anatomic variant calvarial sutures can be mistaken for skull fractures. This article reviews potential pitfalls emergency radiologists may encounter in practice when interpreting pediatric head CTs, including trauma, extra-axial fluid collections, intra-axial hemorrhage, and ventriculoperitoneal shunt complications.

Cardiac MRI of Hereditary Cardiomyopathy.

Hereditary cardiomyopathy comprises a heterogeneous group of diseases of the cardiac muscle that are characterized by the presence of genetic mutations. Cardiac MRI is central to evaluation of patients with cardiomyopathy owing to its ability to allow evaluation of many different tissue properties in a single examination. For example, cine MRI is the standard of care for assessment of myocardial structure and function. It clearly shows regions of asymmetric wall thickening that are typical of hypertrophic cardiomyopathy and allows it to be differentiated from other hereditary disorders such as Fabry disease or transthyretin cardiac amyloidosis that produce concentric hypertrophy. Late gadolinium enhancement provides a different tissue property and allows these latter two causes of concentric hypertrophy to be distinguished on the basis of their enhancement appearances (Fabry disease shows midwall basal inferolateral enhancement, and amyloidosis shows global subendocardial enhancement). Native T1 mapping may similarly allow differentiation between Fabry disease and amyloidosis without the use of contrast material. T2*-weighted MRI is important in the detection and quantification of iron overload cardiomyopathy. Other hereditary entities for which comprehensive MRI has proven essential include Danon disease, familial dilated cardiomyopathy, hereditary muscular dystrophy, arrhythmogenic right ventricular cardiomyopathy, and ventricular noncompaction. As a result of the diagnostic power of cardiac MRI, cardiac MRI examinations are being requested with increasing frequency, not only in academic centers but also in community practices. The genetic background, pathophysiologic characteristics, and clinical presentation of patients with hereditary cardiomyopathy are described; the characteristic cardiac MRI features of hereditary cardiomyopathy are discussed; and the role of MRI in risk stratification, treatment, and prognostication in patients with cardiomyopathy is reviewed. ©RSNA, 2022 Online supplemental material is available for this article.

Fluoroscopic Evaluation of Duodenal Diseases.

The duodenum can be affected by a variety of abnormalities because of its development during embryogenesis and its dual intra- and retroperitoneal location. If small bowel embryogenesis is disturbed, congenital errors occur. Although some congenital variants may be asymptomatic and inconsequential to the patient, other anomalies can result in life-threatening emergencies such as malrotation, leading to midgut volvulus. Many infectious processes affect the duodenum, including duodenal ulcers and opportunistic infection in patients with HIV/AIDS or Crohn disease. Small bowel malignancies are uncommon but important to recognize, because the duodenum can be involved in polyposis syndromes or the development of primary adenocarcinoma, neuroendocrine tumors, lymphoma, and metastasis. Although endoscopy is currently the most used diagnostic method to assess the lumen of the upper gastrointestinal tract, fluoroscopy is a valuable adjunct technique and the study of choice for many diseases, specifically those for which anatomic and functional information is required. Fluoroscopy is also commonly used postoperatively to assess for complications such as obstruction and extraluminal leaks. Compared with endoscopy, fluoroscopy is an inexpensive and noninvasive technique that provides salient anatomic information and allows delineation of the duodenal mucosa and assessment of real-time duodenal motility. The authors examine the broad spectrum of conditions that can involve the duodenum, including congenital, infectious, inflammatory, and neoplastic abnormalities, and review their typical appearances at fluoroscopy. Online supplemental material is available for this article. ©RSNA, 2022.

Imaging review of penile pathologies encountered in the emergency department.

While penile pathology is uncommon, prompt diagnosis and treatment of emergent and urgent penile pathology are necessary to prevent complications. This paper will review the imaging findings of the most common critical penile pathologies, including traumatic, vascular, infectious, foreign body-related, and urethral pathology, in addition to penile prosthesis complications. Each entity will be discussed in the context of presentation and treatment and complications of each pathology will be discussed.

Infiltrative endometriosis without endometrioma: A case report and imaging findings mimicking a bladder malignancy.

Endometriosis affects 10%-15% of women of childbearing age, but the incidence can be as high as 90% in those with chronic pelvic pain. Endometriosis is categorized into ovarian endometriomas, superficial peritoneal implants, and deep infiltrating endometriosis. In this case report a 40-year-old woman gravida 1, para 1 with a history of hysterectomy in Mexico presented with chronic abdominal pain and severe hematuria. Magnetic resonance imaging revealed an infiltrative pelvic mass involving the bladder concerning for a neoplasm that demonstrated subtle hyperintense components on T1-weighted images. The diagnosis of infiltrative endometriosis was established following cystoscopy and tissue sampling. This case highlights the importance of considering endometriosis in the differential for patients with pelvic masses, and recognizing potential features that could suggest the diagnosis.

Medication-induced Pulmonary Injury: A Scenario- and Pattern-based Approach to a Perplexing Problem.

Medication-induced pulmonary injury (MIPI) is a complex medical condition that has become increasingly common yet remains stubbornly difficult to diagnose. Diagnosis can be aided by combining knowledge of the most common imaging patterns caused by MIPI with awareness of which medications a patient may be exposed to in specific clinical settings. The authors describe six imaging patterns commonly associated with MIPI: sarcoidosis-like, diffuse ground-glass opacities, organizing pneumonia, centrilobular ground-glass nodules, linear-septal, and fibrotic. Subsequently, the occurrence of these patterns is discussed in the context of five different clinical scenarios and the medications and medication classes typically used in those scenarios. These scenarios and medication classes include the rheumatology or gastrointestinal clinic (disease-modifying antirheumatic agents), cardiology clinic (antiarrhythmics), hematology clinic (cytotoxic agents, tyrosine kinase inhibitors, retinoids), oncology clinic (immune modulators, tyrosine kinase inhibitors, monoclonal antibodies), and inpatient service (antibiotics, blood products). Additionally, the article draws comparisons between the appearance of MIPI and the alternative causes of lung disease typically seen in those clinical scenarios (eg, connective tissue disease-related interstitial lung disease in the rheumatology clinic and hydrostatic pulmonary edema in the cardiology clinic). Familiarity with the most common imaging patterns associated with frequently administered medications can help insert MIPI into the differential diagnosis of acquired lung disease in these scenarios. However, confident diagnosis is often thwarted by absence of specific diagnostic tests for MIPI. Instead, a working diagnosis typically relies on multidisciplinary consensus. ©RSNA, 2021.

Clinical Manifestations and Medical Imaging of Osteogenesis Imperfecta: Fetal Through Adulthood.

The aim of this paper is to describe the varying clinical and imaging manifestations of Osteogenesis Imperfecta (OI) in the fetus, the child, and the adult. OI is a genetic disorder with mutation of Type 1 and non-type 1 collagen genes that results in disruption of multiple collagen based organ systems, most notably bones, often leading to "brittle bones". Additional features such as blue sclera, dentinogenesis imperfecta, joint and ligamentous hyperlaxity, hearing loss and cardiac defects may be present. Currently, there are at least 30 recognized genetic forms of OI. Given the multiple genes involved, variable genetic inheritance, and the wide range in phenotype, diagnosis can be challenging. While OI may sometimes be diagnosed in the fetus, patients with mild forms of OI may be diagnosed in childhood or even in adulthood. Imaging, including ultrasound, radiography, computed tomography, and magnetic resonance imaging, plays an important role in the diagnoses of OI in the fetus, the child, and the adult. Imaging is also crucial in identifying the many multisystem manifestations of OI. In particular, imaging can help differentiate manifestations of OI from injuries sustained in non-accidental trauma. Age, severity and manner of presentation of OI vary broadly depending on the specific genetic mutation involved, mode of inheritance, and age of the patient. Successful diagnosis of OI hinges on a detailed knowledge of the variable presentation and complications that may be encountered with this disease. CONCLUSION: In conclusion, OI comprises a heterogeneous group of genetic disorders responsible for bone fragility and additional connective tissue disorders, which can result in specific clinical and imaging findings in the fetus, the child, and the adult.

"Undiagnosed aortic coarctation with 2 simultaneous acute aortic syndromes: Intramural hematoma and mycotic aneurysm".

Acute aortic syndrome can be a fatal pathology if not diagnosed and managed early. Although acute aortic syndrome is more often a diagnosis of adulthood, it may occasionally afflict the pediatric patients. We herein present a case of a 5-year-old female that was discovered to have multiple acute and congenital aortic abnormalities after presenting to the emergency department with infectious symptoms and lower extremity pain. Acute aortic syndrome may not be a top differential consideration in children with acute chest pain; however, it is important to consider because delayed diagnosis and management can have fatal implications.

Imaging features of fungal pneumonia in haematopoietic stem cell transplant patients.

Patients who have received haematopoietic stem cell transplantation (HSCT) have a high rate of pulmonary complications, and in this immunosuppressed population, fungal pneumonia is of great concern. Fungal pneumonia can have a similar appearance to non-infectious pulmonary processes in HSCT patients, and radiologists should be familiar with the subtle features that may help to differentiate these disease entities. The focus of this article is on the diagnosis of fungal pneumonia in HSCT patients with an emphasis on radiologists' roles in establishing the diagnosis of fungal pneumonia and the guidance of clinical management.

Approaching diversity and inclusion in the radiology department.

There are numerous benefits to increasing diversity and inclusion within our radiology departments, and both areas need to be a part of our core mission to garner real change. A diverse and inclusive radiology department not only benefits the radiology department, but also our patients and society as a whole. Our paper provides our thoughts on a practical step-by-step guide on how to increase both diversity and inclusion within the radiology workplace, such that every voice can be heard, and every person can be seen.

"The bagel and blob signs in tubal ectopic pregnancy".

An ectopic pregnancy carries the potential for disastrous maternal complications. Early first trimester pelvic ultrasound examinations are frequently obtained in cases of pelvic pain and vaginal bleeding to assess for such diagnoses. The "bagel sign" and the "blob sign" described two sonographic appearances of tubal ectopic pregnancy with positive predictive values of > 95%. Current ectopic pregnancy consensus statements differ in the interpretation of these findings; however, radiologists should have familiarity with the appearances of these findings so as to best educate ordering providers on the potential for presence of a tubal ectopic pregnancy and need for very close patient surveillance.

The role of CT in planning percutaneous structural heart interventions: Where to measure and why.

As research continues to demonstrate successes in the use of percutaneous trans-vascular techniques in structural heart intervention, both the subspecialty trained and non-subspecialty trained cardiac imager find themselves performing and reporting larger amounts of information regarding cardiovascular findings. It is therefore imperative that the imager gains understanding and appreciation for how these various measurements are obtained, as well as their implication in a patient's care. Cardiac gated computed tomography (CT) has solidified its role and ability at providing high resolution images that can be used to obtain the key measurements used in structural heart intervention planning. This manuscript aims to provide an overview of what measurements are necessary to report when interpreting CT examinations purposed for structural heart intervention. This includes a review on indications and brief discussion on complications related to these procedures.

Unilateral axillary lymphadenopathy following COVID-19 vaccination: A case report and imaging findings.

As more people receive coronavirus disease 2019 (COVID-19) vaccinations, the side effects of the vaccines will become more apparent. One reported side effect that has come to light is unilateral axillary lymphadenopathy ipsilateral to the vaccination site. In general, unilateral axillary lymphadenopathy has a broad differential including malignancy, infection, autoimmune disorder, and iatrogenic etiologies. We present a case of a previously healthy 38-year-old woman who received her first dose of Pfizer COVID-19 vaccination 3 days prior to presenting to the emergency department complaining of 2 weeks of abdominal pain and 20-pound unintentional weight loss. Unilateral axillary lymphadenopathy, ipsilateral to the vaccination site, was found on a contrast-enhanced computed tomography examination of the chest, abdomen, and pelvis. Subsequent diagnostic mammograms did not demonstrate evidence of malignancy; however, axillary ultrasound again revealed nonspecific lymphadenopathy. A short-term follow-up axillary ultrasound was recommended, rather than a lymph node biopsy, given the history of recent vaccination. At clinical follow-up, the patient's abdominal pain resolved and no further weight loss was noted. This case report discusses the key components and workup recommendation of unilateral axillary lymphadenopathy in the setting of COVID-19 vaccination.