Imaging Aspects of the Hippocampus.

The hippocampus is one of the most sophisticated structures in the brain, owing to its complex anatomy, intriguing functions, relationship with other structures, and relevant associated symptoms. Despite being a structure analyzed for centuries, its anatomy and physiology in the human body are still being extensively studied, as well as associated pathologic conditions and potential biomarkers. It can be affected by a broad group of diseases that can be classified as congenital, degenerative, infectious or inflammatory, neoplastic, vascular, or toxic-metabolic disease. The authors present the anatomy and close structures, function, and development of the hippocampus, as well as an original algorithm for imaging diagnosis. The algorithm includes pathologic conditions that typically affect the hippocampus and groups them into nodular (space occupying) and nonnodular pathologic conditions, serving as a guide to narrow the differential diagnosis. MRI is the imaging modality of choice for evaluation of the hippocampus, and CT and nuclear medicine also improve the analysis. The MRI differential diagnosis depends on anatomic recognition and careful characterization of associated imaging findings such as volumetric changes, diffusion restriction, cystic appearance, hyperintensity at T1-weighted imaging, enhancement, or calcification, which play a central role in diagnosis along with clinical findings. Some pathologic conditions arising from surrounding structures such as the amygdala are also important to recognize. Pathologic conditions of the hippocampus can be a challenge to diagnose because they usually manifest as similar clinical syndromes, so the imaging findings play a potential role in guiding the final diagnosis. Online supplemental material is available for this article. ©RSNA, 2022.

The diagnostic and prognostic values of inflammatory markers in intraductal papillary mucinous neoplasm.

BACKGROUND: Intraductal papillary mucinous neoplasm (IPMN) is an broad-spectrum disease from benign to malignant. Inflammatory markers are known as prognostic predictors in various diseases. The purpose of this study was to determine the predictive value of inflammatory markers for prognosis in IPMN. METHODS: From April 1995 to December 2016, patients who underwent pancreatectomy with pathologically confirmed IPMN at four tertiary centers were enrolled. Patients with a history of pancreatitis or cholangitis, and other malignancies were excluded. Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and advanced lung cancer inflammation index (ALI) were calculated. RESULTS: Of all, ninety-eight patients (26.8%) were diagnosed as invasive IPMN. The NLR and PLR were significantly elevated in invasive IPMN than in non-invasive disease (2.0 vs 1.8, p = 0.004; 117.1 vs 107.4, p = 0.009, respectively). ALI was significantly higher in non-invasive IPMN than in invasive disease (58.1 vs 45.9, p < 0.001). In multivariate analysis, only NLR showed significant association among the inflammatory markers studied (p = 0.044). In invasive IPMN, the five-year recurrence-free survival rate for NLR less than 3.5 was superior to the rest (59.1 vs 42.2, p = 0.023). CONCLUSION: NLR may help to rightly select IPMN patients who will require surgery and may serve as a useful prognostic factor.