Diagnostic performance of diffusion-weighted imaging versus 18F-FDG PET/CT in differentiating pulmonary lesions: an updated meta-analysis of comparative studies.

OBJECTIVE: To compare the diagnostic accuracy of diffusion-weighted imaging (DWI) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for differentiating pulmonary nodules and masses. METHODS: We systematically searched six databases, including PubMed, EMBASE, the Cochrane Library, and three Chinese databases, to identify studies that used both DWI and PET/CT to differentiate pulmonary nodules. The diagnostic performance of DWI and PET/CT was compared and pooled sensitivity and specificity were calculated along with 95% confidence intervals (CIs). The Quality Assessment of Diagnostic Accuracy Studies 2 was used to assess the quality of the included studies, and STATA 16.0 software was utilized to perform statistical analysis. RESULTS: Overall, 10 studies that enrolled a total of 871 patients with 948 pulmonary nodules were included in this meta-analysis. DWI had greater pooled sensitivity (0.85 [95% CI 0.77-0.90]) and specificity (0.91 [95% CI 0.82-0.96]) than PET/CT (sensitivity, 0.82 [95% CI 0.70-0.90]); specificity, (0.81, [95% CI 0.72-0.87]). The area under the curve of DWI and PET/CT were 0.94 (95% CI 0.91-0.96) and 0.87 (95% CI 0.84-0.90) (Z = 1.58, P > 0.05), respectively. The diagnostic odds ratio of DWI (54.46, [95% CI 17.98-164.99]) was superior to that of PET/CT (15.77, [95% CI 8.19-30.37]). The Deeks' funnel plot asymmetry test showed no publication bias. The Spearman correlation coefficient test revealed no significant threshold effect. Lesion diameter and reference standard could be potential causes for the heterogeneity of both DWI and PET/CT studies, and quantitative or semi-quantitative parameters used would be a potential source of bias for PET/CT studies. CONCLUSION: As a radiation-free technique, DWI may have similar performance compare with PET/CT in differentiating malignant pulmonary nodules or masses from benign ones.

Improving the imaging diagnostic strategy for pulmonary artery masses based on 18F-FDG PET/CT integrated with CTPA.

OBJECTIVE: To evaluate the diagnostic accuracy of computed tomography pulmonary angiography (CTPA) and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) for pulmonary artery (PA) masses. METHODS: Of 2889 patients with PA filling defects of PA on CTPA, 79 consecutive patients suspicious for PA malignancy who subsequently underwent 18F-FDG PET/CT were enrolled. All masses were diagnosed on the basis of pathological findings or clinical imaging follow-up. For each mass, morphological CT signs, standardized uptake value (SUVmax and SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on 18F-FDG PET/CT were used as diagnostic markers. RESULTS: Expansive growth, irregular margin, invasion, CT contrast uptake, and wall eclipse sign were strongly associated with the malignant nature of masses. The coexistence of at least 5 CT signs perfectly identified malignant masses, whereas the detection of no more than 4 CT signs did not accurately discriminate between the natures of masses. Mean SUVmax, SUVmean, MTV, and TLG values were significantly higher in malignant masses compared to those in benign masses. The diagnostic accuracy of 18F-FDG PET/CT parameters (SUV, MTV, and TLG) was excellent in detecting malignant masses. Among patients with 3 or 4 pathological CT signs, SUVmax > 3.4 significantly increased the identification of malignancies. CONCLUSIONS: CTPA is a useful imaging modality for diagnosing PA masses, especially when at least 5 abnormal CT signs are identified. Similarly, 18F-FDG PET/CT accurately identified malignant masses and provided additional valuable information on diagnostic uncertainties after CTPA.

Bilateral versus unilateral balloon pulmonary angioplasty for inoperable chronic thromboembolic pulmonary hypertension.

BACKGROUND: To evaluate the safety and efficacy of bilateral balloon pulmonary angioplasty (BPA) as compared with unilateral BPA for patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). METHOD: We reviewed 210 consecutive BPA sessions for 92 CTEPH patients, including 124 unilateral BPA sessions and 86 bilateral BPA sessions. Radiation exposure, operation details, lesions characteristics and the occurrence of complications were compared between unilateral BPA and bilateral BPA. 131 BPA sessions with a hemodynamics follow-up were included for efficacy analysis, in which hemodynamics changes were compared. Logistic regression analysis was used to identify factors associated with the occurrence of complications. RESULT: Bilateral BPA treated more lobes, arteries and lesions [3 (2, 4) vs. 2 (1, 3) lobes, p < 0.001; 8 (5.5, 10) vs. 6 (4, 8) vessels, p = 0.003; 9 (7, 12) vs. 8 (5, 10) lesions, p = 0.01] in one single session than unilateral BPA in a comparable operation duration and amount of contrast media given. Overall, the occurrence of complications was similar between bilateral BPA and unilateral BPA [9 (10.5%) vs. 12 (9.7%), p = 0.83]. Hemodynamics effects didn't differ significantly between bilateral BPA and unilateral BPA in a single session [mPAP, - 4.5 ± 8.6 vs. - 3.6 ± 7.3 mmHg, p = 0.52; PVR, - 1.1 (- 3.5, 0.8) vs. - 1.8 (- 5.2, 0.3) Wood units, p = 0.21]. For the initial BPA session, bilateral BPA also treated more lobes, arteries and lesions than unilateral BPA [3 (2, 4) vs. 2 (1, 2) lobes, p < 0.001; 8.0 (5.8, 9.3) vs. 6.0 (4.0, 8.0) vessels, p = 0.04; 9 (6, 12) vs. 7 (4, 10) lesions, p = 0.02]. The occurrence of complications was also similar [5 (13.2%) vs. 5 (9.3%), p = 0.80], even in patients with poor baseline hemodynamics. Univariate regression analysis reveals the number of lobes treated/session, but not bilateral BPA, as predictive factors of complications. CONCLUSION: Bilateral BPA may be safely and effectively performed in patients with CTEPH without increasing operation duration and radiation burden, even in patients with unfavorable baseline hemodynamics.

Use of diffusion-weighted magnetic resonance imaging to distinguish between lung cancer and focal inflammatory lesions: a comparison of intravoxel incoherent motion derived parameters and apparent diffusion coefficient.

Background Using imaging techniques to diagnose malignant and inflammatory lesions in the lung can be challenging. Purpose To compare intravoxel incoherent motion (IVIM) and apparent diffusion coefficient (ADC) magnetic resonance imaging (MRI) analysis in their ability to discriminate lung cancer from focal inflammatory lung lesions. Material and Methods Thirty-eight patients with lung masses were included: 30 lung cancers and eight inflammatory lesions. Patients were imaged with 3.0T MRI diffusion weighted imaging (DWI) using 10 b values (range, 0-1000 s/mm2). Tissue diffusivity ( D), pseudo-diffusion coefficient ( D*), and perfusion fraction ( f) were calculated using segmented biexponential analysis. ADC (total) was calculated with monoexponential fitting of the DWI data. D, D*, f, and ADC were compared between lung cancer and inflammatory lung lesions. Receiver operating characteristic analysis was performed for all DWI parameters. Results The ADC was significantly higher for inflammatory lesions than for lung cancer ([1.21 ± 0.20] × 10-3 mm2/s vs. [0.97 ± 0.15] × 10-3 mm2/s; P = 0.004). By IVIM, f was found to be significantly higher in inflammatory lesions than lung cancer ([46.10 ± 12.92] % vs. [29.29 ± 10.89] %; P = 0.005). There was no difference in D and D* between lung cancer and inflammatory lesions ( P = 0.747 and 0.124, respectively). f showed comparable diagnostic performance with ADC in differentiating lung cancer from inflammatory lung lesions, with areas under the curve of 0.833 and 0.826, sensitivity 80.0% and 73.3%, and specificity 75.0% and 87.5%, respectively. Conclusion The IVIM parameter f value provides comparable diagnostic performance with ADC and could be used as a surrogate marker for differentiating lung cancer from inflammatory lesions.

Magnetic Resonance Imaging and Pathologic Findings of 26 Cases With Uterine Adenomatoid Tumors.

OBJECTIVE: To analyze the magnetic resonance imaging (MRI) features and pathologic findings of uterine adenomatoid tumors (ATs) for improved diagnostic accuracy and facilitating differential diagnosis of the tumors. METHODS: We investigated retrospectively 26 patients with uterine ATs confirmed by pathology. Before operation, all patients accepted multiple MRI scans, including T1-weighted image (T1WI), T2-weighted image (T2WI), T2WI/spectrally adiabatic inversion recovery, and T1-weighted enhanced imaging. Two radiologists reviewed all the MRI sequences on PACS workstations for all patients to evaluate the location, shape, size, margin, intensity, and enhancement of ATs. RESULTS: All uterine ATs exhibited either single round solid (n = 24) or predominantly cystic (n = 2) masses with either well-defined (n = 23) or ill-defined margin (n = 3). The diameter range of the tumors was 1.0 to 7.0 cm (mean, 3.8 cm). Solid masses were isointensive on T1WI and hypointensive on T2WI with moderate enhancement. The degree of enhancement in solid tumors was either lower than (18/24 [75%]) or equal to (6/24 [25%]) that of the myometrium. Predominantly cystic masses presented as cystic lesions with a little irregular solid nodule inside. The cystic parts were hypointensive on T1WI and hyperintensive on T2WI without enhancement, whereas the solid nodules were isointensive on both T1WI and T2WI with moderate enhancement. A large part of the uterine ATs (69.2% [18/26]) coexisted with other uterine diseases. On pathology, uterine ATs were characterized as gland-like structures with irregular expansion of tubular cavities, which might be correlated with low enhancement of tumors. The tumors were lined with flat or cuboidal mesothelial cells and residue of smooth muscle component, which might contribute to their hypointensive appearance on T2WI. CONCLUSIONS: Small solid uterine masses with homogeneous hypointensity on T2WI and lower enhancement or cystic lesions with inner irregular solid nodule may indicate the diagnosis of uterine ATs, and final diagnosis can be determined with pathology.