Primary Sjögren syndrome is an immune-mediated exocrinopathy characterized by lymphoplasmacytic infiltration of the salivary and lacrimal glands. Various systemic extraglandular disorders are associated with primary Sjögren syndrome, and the thorax is commonly affected. The pulmonary manifestations of primary Sjögren syndrome may be categorized as airway abnormalities, interstitial pneumonias, and lymphoproliferative disorders; in each category, bronchiectasis or centrilobular nodules, nonspecific interstitial pneumonia, and lymphoid interstitial pneumonia are common. These manifestations do not usually occur in isolation; they are concomitantly seen with other types of lesions. Mucosa-associated lymphoid tissue (MALT) lymphoma and amyloidosis are key components of lymphoproliferative disorders, and MALT lymphoma should always be considered because its morphologic characteristics are similar to those of benign lymphoproliferative disorders. Amyloidosis is rare but important because it carries a risk for underlying MALT lymphoma or plasmacytoma, and it may lead to hemoptysis during biopsy. In addition, thin-walled air cysts are characteristic of primary Sjögren syndrome, irrespective of the main pulmonary manifestations. Lymphadenopathy and multilocular thymic cysts may be seen in the mediastinum. During the follow-up period, there is a risk for acute exacerbation of interstitial pneumonia and development of malignant lymphoma. Often, primary Sjögren syndrome is subclinical, but there are various underlying risks. Thus, imaging findings are important. In addition to the various types of interstitial pneumonia and airway abnormalities, air cysts and mediastinal manifestations may help diagnose primary Sjögren syndrome.
The use of ASL-MRI is sensitive to the perfusion abnormalities and could thus be helpful to estimate functional abnormalities in cerebral hemorrhage patients.
We illustrate the fundamental theoretical principles of arterial spin-labeling (ASL) magnetic resonance imaging (MRI) and show a system that employs the second version of quantitative imaging of perfusion using a single subtraction (Q2TIPS) to quantify cerebral blood flow (CBF). We also discuss the effects of the parameters used in Q2TIPS on CBF values as measured with ASL-MRI.
Background Quantitative evaluation of degeneration of the substantia nigra (SN) is important for early, pre-symptomatic diagnosis of Parkinson’s disease (PD). Accordingly, a clinically feasible imaging and quantification technique are needed. Purpose To investigate the T1 value of the SN in healthy individuals from phase-sensitive inversion recovery (PSIR) images and to clarify its correlation with the SN characteristics on neuromelanin (NM) images to identify an imaging biomarker for early diagnosis of PD. Material and Methods T1-weighted and NM images of the SN from 32 healthy volunteers were obtained using PSIR and turbo spin-echo sequences. The contrast between the SN and cerebral peduncle (CP) and area of the SN were measured; the T1 values of the SN from PSIR images and relationships between the T1 value and age/SN area were evaluated. Results There was a significant negative correlation between age and the SN area obtained using PSIR imaging. The SN area on PSIR images (104.9 ± 20.9 mm2) was significantly larger than that on NM images (72.1 ± 14.9 mm2). There was a significant negative correlation between the SN area and the T1 value of the SN obtained from PSIR images. Conclusion In healthy adults, the area and T1 value of the SN measured on PSIR images were different from those obtained from NM images. This suggests that PSIR imaging may help in the assessment of SN degeneration.
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