Dural and Leptomeningeal Diseases: Anatomy, Causes, and Neuroimaging Findings.

Meningeal lesions can be caused by various conditions and pose diagnostic challenges. The authors review the anatomy of the meninges in the brain and spinal cord to provide a better understanding of the localization and extension of these diseases and summarize the clinical and imaging features of various conditions that cause dural and/or leptomeningeal enhancing lesions. These conditions include infectious meningitis (bacterial, tuberculous, viral, and fungal), autoimmune diseases (vasculitis, connective tissue diseases, autoimmune meningoencephalitis, Vogt-Koyanagi-Harada disease, neuro-Behçet syndrome, Susac syndrome, and sarcoidosis), primary and secondary tumors (meningioma, diffuse leptomeningeal glioneuronal tumor, melanocytic tumors, and lymphoma), tumorlike diseases (histiocytosis and immunoglobulin G4-related diseases), medication-induced diseases (immune-related adverse effects and posterior reversible encephalopathy syndrome), and other conditions (spontaneous intracranial hypotension, amyloidosis, and moyamoya disease). Although meningeal lesions may manifest with nonspecific imaging findings, correct diagnosis is important because the treatment strategy varies among these diseases. ©RSNA, 2023 Online supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article. Quiz questions for this article are available through the Online Learning Center.

Computed tomography findings of early-stage TAFRO syndrome and associated adrenal abnormalities.

OBJECTIVES: To compare CT findings of early (within 3 weeks post-onset)- and later (within 1 month before or after diagnostic criteria were satisfied, and later than 3 weeks post-onset) stage thrombocytopenia, anasarca, fever, reticulin fibrosis, renal dysfunction, and organomegaly (TAFRO) syndrome. METHODS: Between 2014 and 2019, 13 patients with TAFRO syndrome (8 men and 5 women; mean age, 54.9 years) from nine hospitals were enrolled. The number of the following CT findings (CT factors) was recorded: the presence of anasarca, organomegaly, adrenal ischaemia, anterior mediastinal lesion, bony lesion, and lymphadenopathy. Records of adrenal disorders (adrenomegaly, ischaemia, and haemorrhage) throughout the disease course were also collected. Differences in CT factors at each stage were statistically compared between remission and deceased groups. RESULTS: Para-aortic oedema and mild lymphadenopathy were observed in all patients, whereas pleural effusion, ascites, and subcutaneous oedema were found in 5/13, 7/13, and 7/13 cases, respectively, at the early stage. CT factors at the early stage were significantly higher in the deceased than in the remission group (mean, 11 vs 6.5; p = 0.04), while they were nonsignificant at the later stage. Adrenal disorders were present in 7/13 cases throughout the course including 6 of adrenomegaly and 4 of ischaemia at the early stage. CONCLUSIONS: Para-aortic oedema and mild lymphadenopathy are most common at the early stage. Anasarca, organomegaly, lymphadenopathy, and adrenal disorders on early-stage CT are useful for unfavourable prognosis prediction. Moreover, adrenal disorders are frequent even at the early stage and are useful for early diagnosis of TAFRO syndrome. KEY POINTS: • CT findings facilitate early diagnosis and prognosis prediction in TAFRO syndrome. • Adrenal disorders are frequently observed in TAFRO syndrome. • Adrenal disorders are useful for differential diagnosis of TAFRO syndrome.

Uterine adenomyosis with extensive glandular proliferation: case series of a rare imaging variant.

PURPOSE: We aimed to investigate the clinical and magnetic resonance imaging (MRI) characteristics of uterine adenomyosis, in which there is an extensive area of high signal intensity in the myometrium on T2-weighted MRI. METHODS: This retrospective radiographic study reviewed a case series of six patients (mean age, 36 years) with adenomyosis. These patients were selected because, unlike in classical adenomyosis, T2-weighted images showed a larger area of high signal intensity than that of low signal intensity in the myometrium. The morphology of the myometrial lesions, patterns of contrast enhancement (n=4), intramyometrial hemorrhaging, diffusion restriction (n=5), endometrial lesions, and imaging findings after treatment (n=3) were evaluated on MRI. RESULTS: The patients' clinical symptoms included vaginal bleeding and severe anemia. Four were administered hormonal therapy, one underwent hysterectomy, and one underwent enucleation. On T2-weighted images, all showed endometrial thickening and a high signal intensity area in the myometrium that was divided up by a mesh of low signal intensity bands, with an appearance reminiscent of a fish caught in a net. Other findings included gradual centripetal enhancement with contrast defects in multicystic areas (4/4), an intramyometrial hemorrhage (1/6), and increased diffusion (5/5). Following hormonal therapy, the uteruses decreased in size and were similar to those of classical adenomyosis on MRI (3/3). The lesions were diagnosed as adenomyosis with a proliferation of adenomyotic glandular tissue and a proliferative endometrial polyp. CONCLUSION: This case series suggests that there is a subgroup of uterine adenomyosis that shows a characteristic "fish-in-a-net" appearance on T2-weighted images.

Exfoliation of Alveolar Rhabdomyosarcoma Cells in the Ascites of a 50-Year-Old Woman: Diagnostic Challenges and Literature Review.

Alveolar rhabdomyosarcoma (ARMS) is a nonepithelial tumor with skeletal muscle differentiation and typically affects adolescents and young adults. The cytological features of ARMS in body fluid have not been well characterized, which complicates diagnosis. Here, we describe the cytological features of ARMS in the ascites of a 50-year-old woman with an intra-abdominal mass and abundant ascites. Aspiration cytology of ascitic fluid revealed numerous small discohesive round cells with mild nuclear atypia and prominent nucleoli. Rhabdomyoblastic cells, characteristic of rhabdomyosarcoma, were identified rarely. Cannibalism and 'window' formation, as seen in reactive mesothelial cells, complicated the diagnosis of ARMS. Histological examination established the diagnosis of ARMS, which was confirmed by immunohistochemical expression of myogenic markers. When diagnosing ARMS from effusion samples, the diagnostic problems associated with the morphological similarity of ARMS cells to reactive mesothelial cells should be considered.

Usefulness of Color Coding Resected Samples from a Pancreaticoduodenectomy with Tissue Marking Dyes for a Detailed Examination of Surgical Margin Surrounding the Uncinate Process of the Pancreas.

BACKGROUND: Characteristics of a cancer-positive margin around a resected uncinate process of the pancreas (MUP) due to a pancreticoduodenectomy are difficult to understand by standardized evaluation because of its complex anatomy. The purposes of this study were to subclassify the MUP with tissue marking dyes of different colors and to identify the characteristics of sites that showed positivity for cancer cells in patients with pancreatic head carcinoma who underwent circumferential superior mesenteric arterial nerve plexus-preserving pancreaticoduodenectomy. Results of this evaluation were used to review operation procedures and perioperative methods. METHOD: We divided the MUP into 4 sections and stained each section with a different color. These sections were the pancreatic head nerve plexus margin (Area A), portal vein groove margin (Area B), superior mesenteric artery margin (Area C), and left of the superior mesenteric artery margin (Area D). The subjects evaluated were 45 patients who had carcinoma of the pancreatic head and were treated with circumferential superior mesenteric arterial nerve plexus-preserving pancreaticoduodenectomy. RESULTS: Of the 45 patients, nine cases (90%) of incomplete resection showed cancer-positivity in the MUP. Among the 4 sections of the MUP, the most cases of positive results [MUP (+) ] were found in Area B, with Area A (+), 0 case; Area B (+), 6 cases; Area C (+), 2 cases; and Area D (+), 3 cases (total, 11 sites in 9 patients). Relapse occurred in 7 of the 9 patients with MUP (+). Local recurrence was observed as initial relapse in all 3 patients with Area D (+). In contrast, the most common site of recurrence other than that in patients with Area D (+) was the liver. CONCLUSION: By subclassifying the MUP with tissue marking dyes of different colors, we could confirm regional characteristics of MUP (+). As a result, circumferential superior mesenteric arterial nerve plexus-preserving pancreticoduodenectomy was able to be performed in R0 operations in selected patients while a better postoperative quality of life was maintained. Furthermore, Area D (+) represents an extension beyond the limit of the local disease and may indicate the need for early aggressive adjuvant chemotherapy.

Endovenous Treatment for Acute Massive Pulmonary Thromboembolism.

Treatment for venous thromboembolic conditions differs significantly depending on whether the condition is acute or chronic. Endovenous treatment is now available for treating the most severe cases of acute massive pulmonary thromboembolism, and the goal is rapid central clot removal to relieve life-threatening pulmonary circulation. Endovenous catheter interventions include catheter-directed thrombolysis and catheter-assisted thrombus removal. The latter is divided into aspiration thrombectomy, fragmentation, and rheolytic thrombectomy. Data from cohort studies indicate that the clinical outcome and safety after open surgical treatment and endovenous treatment may be comparable. This paper reviews the current approaches to endovenous treatment for acute massive pulmonary thromboembolism, and presents our study of hybrid treatment using a combination of local fibrinolysis, mechanical fragmentation, and clot aspiration.

Angiography-assisted computed tomography for the detection and intervention of a subtle aneurysm of the omentum.

Intra-abdominal hemorrhage caused by omental artery rupture is a rare condition traditionally diagnosed via exploratory laparotomy in hemodynamically unstable patients. We experienced a case in which contrast-enhanced multidetector computed tomography (MDCT) and digital subtraction angiography did not identify the rupture site, whereas CT during left omental arteriography depicted a small 4-mm aneurysm. The lesion was then embolized with microcoils and N-butyl cyanoacrylate lipiodol glue. We consider that performing a CT during selective arteriography could be useful in cases in which the rupture site is unclear with other imaging techniques such as contrast-enhanced MDCT and digital subtraction angiography.