Sarcoid-like reaction-computed tomography features in 12 patients.

PURPOSE: The aim of the study was to analyze the computed tomography (CT) findings of sarcoid-like reaction caused by underlying malignancy or immune modulation. METHODS: Twelve patients with pathologically proven sarcoidosis from underlying causes (malignancies, hepatitis C infection, and immune-modulatory treatment) in 2001 to 2011 were identified. All patients had chest CT scans, which were reviewed by 3 experienced thoracic radiologists. Medical records were also reviewed. Follow-up imaging, available in 11 patients, was assessed for response. RESULTS: All patients were white, 8 women and 4 men, with ages ranging from 26 to 72 years. Seven had underlying malignancy, 2 had inflammatory bowel disease, and 3 had liver disease caused by chronic hepatitis C viral infection. On CT, 92% (11/12) of patients had lymphadenopathy, 75% (9/12) had pulmonary nodules less than 5 mm, and 50% (6/12) had ground-glass opacity (GGO). In 42% (5/12) of patients, the dominant finding was discrete nodules (1-5 mm). In 33% (4/12) of patients, the dominant finding was ultrafine nodules with confluence, mimicking GGO. The most common distribution of lung nodules was perilymphatic, found in 78% (7 of the 9 patients with lung nodules). Follow-up was available in 10 patients, limited follow-up in 1, and no follow-up in 1. Six of the 11 patients who had follow-up had complete resolution of CT findings, 3 had partial resolution, and 2 had no resolution. CONCLUSIONS: Imaging features of patients with sarcoid-like reaction include lymphadenopathy, small nodules, and ultrafine nodules with confluence, mimicking GGO. Ultrafine nodules with confluence mimicking GGO were unexpectedly common in this series.

MR findings in iatrogenic Gerbode defect.

Congenital or acquired communication between left ventricle and right atrium is rare and can be easily overlooked as an eccentric tricuspid regurgitation jet. MRI is the ideal modality for accurate diagnosis, providing details for surgical planning about the location and size of the defect.

Lens-free optical tomographic microscope with a large imaging volume on a chip.

We present a lens-free optical tomographic microscope, which enables imaging a large volume of approximately 15 mm(3) on a chip, with a spatial resolution of < 1 µm × < 1 µm × < 3 µm in x, y and z dimensions, respectively. In this lens-free tomography modality, the sample is placed directly on a digital sensor array with, e.g., ≤ 4 mm distance to its active area. A partially coherent light source placed approximately 70 mm away from the sensor is employed to record lens-free in-line holograms of the sample from different viewing angles. At each illumination angle, multiple subpixel shifted holograms are also recorded, which are digitally processed using a pixel superresolution technique to create a single high-resolution hologram of each angular projection of the object. These superresolved holograms are digitally reconstructed for an angular range of ± 50°, which are then back-projected to compute tomograms of the sample. In order to minimize the artifacts due to limited angular range of tilted illumination, a dual-axis tomography scheme is adopted, where the light source is rotated along two orthogonal axes. Tomographic imaging performance is quantified using microbeads of different dimensions, as well as by imaging wild-type Caenorhabditis elegans. Probing a large volume with a decent 3D spatial resolution, this lens-free optical tomography platform on a chip could provide a powerful tool for high-throughput imaging applications in, e.g., cell and developmental biology.