Case of Isolated Absence of the Azygos Vein: Evaluation Using Photon-counting Detector CT.

The isolated absence of the azygos vein was incidentally found on computed tomography (CT) examination in a 60-year-old female. The exact anomaly can be evaluated on high-resolution images of 0.4-mm slice thickness with low keV using photon-counting detector CT. The azygos vein, including the azygos arch, was absent, and a mildly dilated hemiazygos vein flowed to the left brachiocephalic vein through the left superior intercostal vein. A hemiazygos vein connected the left renal vein at the level of the first lumbar vertebra. This patient was the second patient to undergo evaluation using volume rendering images. High-resolution maximum-intensity projection images were useful for assessing the anatomy. Radiation dose was decreased compared with that in conventional CT.

Utility of Echo-planar Imaging with Compressed Sensitivity Encoding (EPICS) in the Evaluation of Small Breast Cancers Using Diffusion-weighted Imaging with Background Suppression (DWIBS).

PURPOSE: High b-value acquisition and diffusion-weighted imaging with background suppression (DWIBS) are desirable in high-specificity breast cancer diagnosis on non-contrast-enhanced magnetic resonance imaging; however, this inherently results in a lower signal-to-noise ratio (SNR). Compressed sensitivity encoding (C-SENSE), which combines SENSE with compressed sensing, improves the SNR by reducing noise. Recent technological improvements allow us to incorporate this acceleration technique into echo-planar imaging, called echo-planar imaging with C-SENSE (EPICS). This study aimed to compare image quality and reliability of the apparent diffusion coefficient (ADC) between DWIBS obtained using SENSE and EPICS in patients with small breast cancers. METHODS: Thirty-seven patients with pathologically confirmed breast cancer underwent DWIBS, and images were reconstructed using both conventional SENSE (SENSE-DWIBS) and EPICS (EPICS-DWIBS). Two board-certified radiologists independently evaluated lesion conspicuity (LC) and noise using a 5-point grading scale. The same 2 radiologists independently measured SNR, contrast-to-noise ratio (CNR), and the mean cancer ADC. The Pearson coefficient and Bland-Altman plot were applied to assess the accuracy of ADCs. RESULTS: LC scores were higher with EPICS than with SENSE, reaching significance for one reviewer but not the other reviewer. Noise ratings on visual evaluation were significantly lower with EPICS than with SENSE (P < 0.001 for both reviewers). SNR was significantly higher with EPICS than with SENSE (P < 0.005 for both reviewers). CNR was significantly higher with EPICS than with SENSE (P < 0.001 for both reviewers). Bland-Altman plots of cancer ADCs using EPICS-DWIBS and SENSE-DWIBS showed excellent concordance, with a bias of 0.026 × 10-3 mm2/s and limits of agreement ranging 0.054 × 10-3 mm2/s; the Pearson's correlation coefficient was 0.997 (P < 0.0001). CONCLUSION: EPICS enhances breast DWIBS image quality, with improved SNR and CNR and reduced noise levels. The ADCs of breast cancers obtained using EPICS were almost perfectly correlated with those obtained using conventional SENSE.

Non-enhanced and Non-gated MR Angiography for Robust Visualization of Peripheral Arteries Using Enhanced Acceleration-selective Arterial Spin Labeling (eAccASL).

This study aimed to assess the feasibility for applying enhanced acceleration-selective arterial spin labeling (eAccASL) to non-electrocardiogram-gated and non-enhanced peripheral MRA. We compared eAccASL and background suppressed single shot turbo field echo (TFE)-triggered angiography non-contrast-enhanced sequence (BASS TRANCE) required electrocardiographic-gating in eight volunteers and three patients. In the volunteer study, eAccASL demonstrated a comparable arterial visualization compared with BASS TRANCE. In patient observation, the advantages with eAccASL were found in arterial visualization on the collateral vessels and without artifacts affected by arrhythmia events.

Persistent left superior vena cava with absent right superior vena cava in adults: CT and clinical findings.

PURPOSE: Persistent left superior vena cava (PLSVC) with absent right superior vena cava (ARSVC) is rare. We evaluated CT and clinical findings of adults with ARSVC. MATERIALS AND METHODS: Our study included 11 adults with ARSVC (mean age, 63 ± 17 years). We evaluated CT findings of the azygos vein system and coronary sinus (CS) using thin slice data of > 64 MDCT. Arrhythmia and congenial heart disease were assessed. We compared the CS diameters between the ARSVC group and the control group of 120 adults with normal vena cava (mean age, 60 ± 4 years). RESULTS: Adults with ARSVC had no azygos vein arch and the hemiazygos vein continued to PLSVCs via the superior intercostal vein. Eight adults had arrhythmia including conduction disturbance and one arrhythmia was associated with atrial septal defect. All adults with ARSVC had dilated CS larger than 11 mm. The mean diameter of the CS in the ARSVC group was 18.4 mm, and that of the control group was 6.8 mm. CS diameter in the ARSVC group was larger than that in the control group (p < 0.001). CONCLUSION: Adults with ARSVC had dilated CS and no azygos vein arch. Four adults had conduction disturbance.

Cutaneous Metastases from Testicular Diffuse Large B-cell Malignant Lymphoma and Bowen Disease: 18F-FDG PET-CT Findings.

Here, we report the case of cutaneous metastases from testicular diffuse large B-cell malignant lymphoma (DLBCL) concurrent with Bowen disease evaluated with 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET-CT). A 60-year-old male underwent orchiectomy to remove his left testicle because of DLBCL. Multiple skin lesions appeared 1 month postoperatively. Furthermore, an intractable erythematous plaque localized to the right lower leg was present from 2 years before the operation. 18F-FDG PET-CT images revealed multiple skin lesions with marked FDG uptakes in the face, neck, and thigh of this patient, as well as a lower leg lesion with minimal FDG uptake. Biopsy of both lesions revealed cutaneous metastases from DLBCL and Bowen disease (BD) of the lower leg lesion. 18F-FDG PET-CT images following chemotherapy and resection of BD demonstrated no FDG uptake.