Simultaneous Evaluation of Lung Anatomy and Ventilation Using 4D Respiratory-Motion-Resolved Ultrashort Echo Time Sparse MRI.

BACKGROUND: Computed tomography (CT) and spirometry are the current standard methods for assessing lung anatomy and pulmonary ventilation, respectively. However, CT provides limited ventilation information and spirometry only provides global measures of lung ventilation. Thus, a method that can enable simultaneous examination of lung anatomy and ventilation is of clinical interest. PURPOSE: To develop and test a 4D respiratory-resolved sparse lung MRI (XD-UTE: eXtra-Dimensional Ultrashort TE imaging) approach for simultaneous evaluation of lung anatomy and pulmonary ventilation. STUDY TYPE: Prospective. POPULATION: In all, 23 subjects (11 volunteers and 12 patients, mean age = 63.6 ± 8.4). FIELD STRENGTH/SEQUENCE: 3T MR; a prototype 3D golden-angle radial UTE sequence, a Cartesian breath-hold volumetric-interpolated examination (BH-VIBE) sequence. ASSESSMENT: All subjects were scanned using the 3D golden-angle radial UTE sequence during normal breathing. Ten subjects underwent an additional scan during alternating normal and deep breathing. Respiratory-motion-resolved sparse reconstruction was performed for all the acquired data to generate dynamic normal-breathing or deep-breathing image series. For comparison, BH-VIBE was performed in 12 subjects. Lung images were visually scored by three experienced chest radiologists and were analyzed by two observers who segmented the left and right lung to derive ventilation parameters in comparison with spirometry. STATISTICAL TESTS: Nonparametric paired two-tailed Wilcoxon signed-rank test; intraclass correlation coefficient, Pearson correlation coefficient. RESULTS: XD-UTE achieved significantly improved image quality compared both with Cartesian BH-VIBE and radial reconstruction without motion compensation (P < 0.05). The global ventilation parameters (a sum of the left and right lung measures) were in good correlation with spirometry in the same subjects (correlation coefficient = 0.724). There were excellent correlations between the results obtained by two observers (intraclass correlation coefficient ranged from 0.8855-0.9995). DATA CONCLUSION: Simultaneous evaluation of lung anatomy and ventilation using XD-UTE is demonstrated, which have shown good potential for improved diagnosis and management of patients with heterogeneous lung diseases. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:411-422.

PET/MRI for the evaluation of patients with lymphoma: initial observations.

OBJECTIVE: The objective of our study was to assess the role of recently introduced hybrid PET/MRI in the evaluation of lymphoma patients using PET/CT as a reference standard. SUBJECTS AND METHODS: In this prospective study 28 consecutive lymphoma patients (18 men, 10 women; mean age, 53.6 years) undergoing clinically indicated PET/ CT were subsequently imaged with PET/MRI using residual FDG activity from the PET/ CT study. Blinded readers evaluated PET/CT (reference standard), PET/MRI, and diffusion-weighted imaging (DWI) studies separately; for each study, they assessed nodal and extranodal involvement. Each FDG-avid nodal station was marked and compared on DWI, PET/MRI, and PET/CT. Modified Ann Arbor staging was performed and compared between PET/MRI and PET/CT. The maximum standardized uptake value (SUVmax) on PET/MRI for FDG-avid nodal lesions was compared with the SUVmax on PET/CT. The apparent diffusion coefficient (ADC) for FDG-avid nodal lesions was compared to SUVmax on PET/MRI. RESULTS: Fifty-one FDG-avid nodal groups were identified on PET/CT in 13 patients. PET/MRI identified 51 of these nodal groups with a sensitivity of 100%. DWI identified 32 nodal groups for a sensitivity of 62.7%. PET/MRI staging and PET/CT staging were concordant in 96.4% of patients. For the one patient with discordant staging results, disease was correctly upstaged to stage IV on the basis of the PET/MRI finding of bone marrow involvement, which was missed on PET/CT. DWI staging was concordant with PET/CT staging in 64.3% of the patients. The increased staging accuracy of PET/MRI relative to DWI was significant (p=0.004). SUVmax measured on PET/MRI and PET/CT showed excellent statistically significant correlation (r=0.98, p<0.001). There was a poor negative correlation between ADC and SUVmax (r=-0.036, p=0.847). CONCLUSION: PET/MRI can be used to assess disease burden in lymphoma with sensitivity similar to PET/CT and can be a viable alternative for lymphoma staging and follow-up.

Mixed Adenoneuroendocrine Carcinoma of the Gastroesophageal Junction: A Rare Find.

Neoplastic lesions that demonstrate neuroendocrine features are rare. However, esophageal tumors containing both adenocarcinomatous and neuroendocrine components are exceedingly rare. Mixed adenoneuroendocrine carcinomas (MANECs) are gastrointestinal tumors with both adenocarcinomatous and neuroendocrine differentiation. They have a tendency for early metastases but clinically manifest relatively late. Imaging studies are often nonspecific with regard to tumor type, and a histopathologic study of biopsy material is required for definitive diagnosis. The overall prognosis is poor. The current report describes a rare case of gastroesophageal MANEC tumor, with approximately 60% neuroendocrine and 40% adenocarcinomatous components. Since there is a dearth of concrete management guidelines for MANECs, we present possible management options to add to the existing literature.

Macular hole surgery prognostic success rates based on macular hole size.

BACKGROUND AND OBJECTIVE: To evaluate the correlation between macular hole (MH) surgery outcomes and preoperative factors believed to affect surgical success rates. PATIENTS AND METHODS: A retrospective, consecutive case series was designed to evaluate the correlation between anatomic success and preoperative factors: MH duration prior to surgery, visual acuity (VA), and MH diameter measured by optical coherence tomography (OCT) at the base and the narrowest midpoint. RESULTS: A total of 153 eyes were enrolled. There was no significant difference in mean duration prior to surgery for MH success and failure (P = .13). Mean preoperative VA was significantly better for MH success than failure (P = .03). Mean mid-hole diameter (P < .001) and mean base-hole diameter (P < .001) were significantly less for MH success than failure. Failure rate was 0% among eyes with mid-hole diameter less than 500 microns and 14.9% with mid-hole 500 microns or greater (P < .001). Failure rate was 0% among eyes with base-hole diameter less than 500 microns, 1.4% with base-hole 500 to 999 microns, and 19.1% with base-hole of 1,000 microns or greater (P = .001). CONCLUSION: Preoperative VA, mid-hole diameter, and base-hole diameter are correlated with anatomic success in MH surgery. An excellent surgical prognosis exists for MHs with mid-hole diameter less than 500 microns and base-hole less than 1,000 microns.