Intraperitoneal anatomy with the aid of pathologic fluid and gas: An imaging pictorial review.

The peritoneum is a large serosal membrane enveloping the abdomen and pelvic organs and forming the peritoneal cavity. This complex relationship forms many named abdominopelvic spaces, which are frequently involved in infectious, inflammatory, neoplastic, and traumatic pathologies. The knowledge of this anatomy is essential to the radiologist to localize and describe the extent of the disease accurately. This manuscript provides a comprehensive pictorial review of the peritoneal anatomy to describe pathologic fluid and gas.

Myoepithelioma-like hyalinizing epithelioid tumor of the foot with OGT-FOX03 fusion gene: Imaging findings, surgical implications, and pathological correlates.

Myoepithelioma-like hyalinizing epithelioid tumors are rare neoplasms that share morphological characteristics of myoepitheliomas but lack traditional immunophenotypic findings. Though little is known about these tumors at present, a handful of recent studies have confirmed that they harbor a novel fusion gene known as "OGT-FOXO." Though closely resembling myoeptheliomas, Myoepithelioma-like hyalinizing epithelioid tumors are considered a distinct tumor entity, and few studies have explored their clinical characteristics or their potential for malignancy. Furthermore, literature describing imaging findings of these tumors is virtually non-existent. Understanding the radiological and pathological differences between Myoepithelioma-like hyalinizing epithelioid tumors and myoepitheliomas is helpful in developing a comprehensive differential for soft tissue neoplasms of the foot. We describe a case of MHET of the foot and correlate MRI findings with pathology in addition to describing surgical technique and implications to care.

18 F-FDG PET/CT Findings of Leptomeningeal Metastasis in Nasopharyngeal Carcinoma.

ABSTRACT: Nasopharyngeal carcinoma (NC) is an epithelial tumor with distinctive prevalence in East and Southeast Asia. Most patients with NC only experience regional metastasis. In cases of distant metastasis, prognosis is grim. Leptomeningeal spread of the disease is a rare occurrence, which is sparsely described in the literature. We present a case of a 33-year-old man with a history of high-grade NC with leptomeningeal metastasis. Initial MRI lumbar spine demonstrated subtle findings consistent with leptomeningeal disease. These findings are easily discernible on 18 F-FDG PET/CT.

PET/MRI imaging in neuroendocrine neoplasm.

Molecular imaging plays a vital role in the management of neuroendocrine neoplasms (NENs). Somatostatin receptor (SSTR) PET is critical for evaluating NENs, ascertaining peptide receptor radionuclide therapy (PRRT) eligibility, and treatment response. SSTR-PET/MRI can provide a one-stop-shop multiparametric evaluation of NENs. The acquisition of complementary imaging information in PET/MRI has distinct advantages over PET/CT and MR imaging acquisitions. The purpose of this manuscript is to provide a comprehensive overview of PET/MRI and a current review of recent PET/MRI advances in the diagnosis, staging, treatment, and surveillance of NENs.

Retroperitoneal anatomy with the aid of pathologic fluid: An imaging pictorial review.

The retroperitoneum, a complex anatomical space within the abdominopelvic region, encompasses various vital abdominal organs. It is compartmentalized by fascial planes and contains potential spaces critical in multiple disease processes, including inflammatory effusions, hematomas, and neoplastic conditions. A comprehensive understanding of the retroperitoneum and its potential spaces is essential for radiologists in identifying and accurately describing the extent of abdominopelvic disease. This pictorial review aims to describe the anatomy of the retroperitoneum while discussing commonly encountered pathologies within this region. Through a collection of illustrative images, this review will provide radiologists with valuable insights into the retroperitoneum, facilitating their diagnostic proficiency to aid in appropriate patient clinical management.

Uterine Sarcoma Presenting as Hypercapnic Respiratory Failure.

Thyroid cancer is a type of malignancy that is considered to have a low morbidity and an indolent disease course in most patients. Though some of its pathologic variants such as anaplastic carcinoma may present with advanced disease staging, it is important to consider the possibility of metastasis to thyroid which may present like a thyroid primary. Solid organ carcinomas form the bulk of the uncommon metastasis to the thyroid, though sarcomas from various organs also rarely exhibit this activity. Literature demonstrating sound diagnostic criteria for these occurrences is sparse. We present a case of uterine sarcoma with distant metastasis to the thyroid gland that initially presented as hypercapnic respiratory failure. Only an inpatient episode of uterine bleeding prompted our team to explore the potential of a metastatic process. Our diagnosis was made utilizing a multidisciplinary approach that we feel is important for clinicians dealing with metastatic disease to the thyroid. In addition to sound physical exam, and use of appropriate imaging modality, we feel it is essential to utilize a detailed cytohistologic specimen evaluation, immunohistochemistry, and genetic sequencing to effectively work up such patients. Although our patient did not survive her hospital stay, we hope this paper brings greater awareness of this malignancy and acts as a benchmark for diagnosing such an unusual remote primary.

Jejunal Adenocarcinoma: A Rare Cause of Small Bowel Obstruction.

Jejunal adenocarcinoma (JA) is both a rare type of gastrointestinal malignancy and an uncommon cause of small bowel obstruction (SBO). It typically presents with vague symptoms, such as abdominal pain, nausea, vomiting, and, in some cases, weight loss. Due to this vague presentation as well as lack of definitive imaging techniques, diagnosis tends to be delayed and patients typically present at later stages. We present a case of a patient who presented with acute onset abdominal pain. Imaging revealed the presence of an SBO with the presence of a suspicious small bowel stricture. He eventually underwent upper endoscopy to find the mass, with subsequent biopsy indicating JA. We hope to bring greater awareness to jejunal carcinoma as a potent cause of SBO in adults.

Multimodality imaging of adrenal gland pathologies: A comprehensive pictorial review.

The assessment of acute abdominal and pelvic emergencies typically involves a multimodal approach consisting of plain radiographs, ultrasound, computed tomography (CT), and rarely magnetic resonance imaging (MRI). Although MRI is not traditionally employed in acute care settings, there are several instances in which MRI provides superior functional and prognostic information. In this manuscript, we highlight multimodal findings of adrenal gland emergencies: Hemorrhage, infarction, and infection. The purpose of our study is to highlight significant findings in various modalities, including CT, MRI, ultrasound, and PET/CT. Due to the scarcity of published data and limited clinical use, primary ultrasound findings are limited in our multimodal review. In conclusion, we find that synergistic use of CT, MRI, and functional imaging provides an effective tool for evaluation and management of adrenal pathology.

A Simple Target Will Save the Day and the Kidney: This Is How We Perform Our Endovascular Fenestrated Graft Procedure.

With the advent of state-of-the-art imaging modalities, increasing population age, and advanced preventive medical treatments, medical device design attempts to keep up with procedural demand. An abdominal aortic aneurysm (AAA) is a recognized, potentially fatal disease process where strides have been made in screening, detection, and treatment since its discovery. With the introduction of percutaneous endograft procedures in 1991, open surgical treatment is nearly a lost art. Endovascular aortic repair is now the gold standard. However, short landing zone necks, hostile angulation, and markedly dilated seal zones present challenges for one size fits all endovascular aortic devices. Suprarenal and juxtarenal fenestrated aortic grafts are the most advanced individually customized grafts invented to date. Subsequently, proper placement of these complex devices still presents challenges. We present a method for preoperative renal stent placement for target purposes. This article includes a pictorial guide and describes the tips and pitfalls for easy proper AAA exclusion with a fenestrated aortic graft. We were successful in the deployment of the fenestrated graft device and the exclusion of an aortic aneurysm while preserving the patency of the renal arteries. The patient had no postoperative complications. During 18-month postoperative surveillance, imaging demonstrated proper graft positioning without evidence of an endoleak. In fenestrated endovascular aortic repair, preoperative renal stenting is paramount for targeting purposes. This allows for the precise and timely deployment of the renal limbs through the fenestrations while minimizing the risk of postoperative complications, including renal artery occlusion.

Use of Cardiac MRI in the Diagnosis of Rare Right Ventricular Noncompaction.

Ventricular noncompaction, also previously known as spongy myocardium, is an inherited primary genetic cardiomyopathy. Noncompaction of the left ventricle is seen in the general population typically in the setting of other congenital heart defects and can be a cause of significant morbidity and mortality. Right ventricular noncompaction is a rare form of cardiomyopathy with no definitive diagnostic criteria. Diagnosis of noncompaction of the right ventricle can be concluded using guidance from the diagnostic criteria for left ventricular noncompaction with multi-modality imaging.

MR diagnosed chronic exertional compartment syndrome successfully treated by endoscopically-assisted fasciotomy.

Chronic exertional compartment syndrome is a subset of compartment syndrome that most frequently affects the lower extremities, often in athletic persons. It is most often characterized by calf pain shortly after the initiation of exercise and resolution of the pain soon after rest. While the pathophysiology is not completely understood, it is believed that compartment a lack of fascial compliance and increased compartment fluid leads to increased pressure, ultimately leading to a reversible ischemic state. Chronic exertional compartment syndrome was once considered a diagnosis of exclusion; however, needle manometry is an invasive way to measure intracompartmental pressure. Similarly, fasciotomy is the treatment of choice but is not without complications. We describe a case of chronic exertional compartment syndrome diagnosed by two-stage MRI and successfully treated by endoscopically-assisted fasciotomy.

Portal Vein Tumor Thrombus: No Longer a Death Sentence.

Hepatocellular carcinoma (HCC) is the most common malignancy of the liver and a leading cause of cancer mortality worldwide. HCC commonly results from longstanding liver cirrhosis, which presents a host of complications and a severely diminished quality of life. Despite advancements in diagnosis, molecular pathogenesis, and management of the complications associated with irreversible liver diseases, HCC remains an aggressive malignancy with high mortality. HCC is often invasive to adjacent vasculature, including the inferior vena cava (IVC) and portal veins, which present with rapid morbidity and patient decline. This article describes a patient with cirrhosis and HCC previously treated with cryoablation now presenting with multiple new foci and invasion of the left medial portal vein. These lesions were synchronously cryoablated. Cryoablation is typically reserved for solid tumor masses within the soft tissue or specific organs. This report illustrates a technique of directly cryoablating tumors within vessels. We achieved adequate cryoablation of the intravascular HCC portal vein tumor thrombus in the left medial portal vein. A one-month follow-up CT scan demonstrated significant portal vein macrovascular invasion (MVI) regression from 22.8 mm to 7.7 mm. Portal vein invasion by HCC presents unique challenges and traditionally precludes percutaneous or surgical therapy. Our technique shows successful cryoablation of MVI as a viable adjunct to treatment in select patients.

Expanding the Frontiers of Treatment: Cryoablation of an Ovarian Mass.

The ovaries are a common site of metastasis from a variety of solid organ malignancies. These tumors most commonly originate from the gastrointestinal tract. Neuroendocrine tumors of the small bowel are unrelenting in their tendency to exhibit this type of distant spread, which poses a challenge for curative treatment. Whether metastatic disease to the ovary or primary ovarian malignancy, this is a major cause of morbidity and mortality for women of various ages. Currently, a mainstay of palliative treatment for advanced-stage disease resides in surgical debulking and chemotherapy. At times, these patients may not be surgical candidates due to various reasons which may include a large disease burden. Computed tomography-guided percutaneous cryoablation is a minimally invasive technique that has shown promise in treating solid organ metastatic lesions by exposing them to lethal temperatures. We describe a novel technique of palliative cryoablation of a primary small bowel carcinoid tumor that metastasized to the ovary. Hydrodissection was utilized to create a window for safe percutaneous treatment. At the end of freeze cycles, intraoperative CT was performed, demonstrating greater than 90% incorporation of the ovarian tumor within the margins of the lethal ice zone. Our team decided that this was a maximum percentage of freeze due to neighboring vessels and bowel. The patient tolerated this treatment well, and there were no reported post-operative complications. The procedure was clinically successful at shrinking the tumor as demonstrated on a nine-month follow-up CT. Percutaneous cryoablation is already a widely utilized method for treating tumors in various locations including the kidneys and liver. The application of cryoablation can be expanded as an effective and safe palliative technique for treating ovarian tumors. This may be especially useful in patients that are not surgical candidates.

Therapeutic strategies for uncommon testis cancer histologies: teratoma with malignant transformation and malignant testicular sex cord stromal tumors.

Testicular cancer is the most common solid malignancy in male adolescents and young adults, with germ cell derived seminomas and non-seminomas being by far the most common histologies. Teratoma with somatic-type malignancy is a rare chemo-resistant phenotype of testis cancer associated with poor prognosis in patients with advanced stage disease. Malignant gonadal-stromal tumors comprise 5% of testicular neoplasms and approximately 10% are malignant and considered chemo-radiation resistant. Prognostic factors and treatment strategies for these uncommon histologies are lacking.