Table 2. Characteristics of DWI of included studies.
| Study, year | Field strength | Imaging evaluation | B value (s/mm2) | Number of reporting radiologists | Pulse sequences | Diagnostic criteria |
|---|---|---|---|---|---|---|
| Giganti, 2017 | 1.5T | QL and QN | 0, 600 | Two radiologists (independently) | Multiplanar T2-weighted study, followed by a DW-MRI protocol and a dynamic T1-weighted study | Quantitative measurements were obtained tracing a small region of interest on the ADC map, so as to minimize partial volume effects |
| Giganti, 2016 | 1.5T | QL | 0, 600 | Two radiologists (independently) | Dynamic T1WI with fat suppression, T2WI with and without fat suppression, DWI | SAD ≥ 6 mm for round perigastric LNs and hyperintensity on DWI |
| Hasbahceci,2015 | 1.5T | QL and QN | 50, 400 and 800 | One radiologist | Axial and coronal TSE-T1WI, axial and coronal fat saturated TSE-T2WI, axial and coronal SPGR-T1WI, axial T2W fat saturated sequence, axial SS-SE-EP DWI with a selective fat suppression | QL: SAD ≥ 5 mm with heterogeneous enhancement, or heterogeneous signal intensity than muscle as seen on DWI. QN: ADC value < 1.1 × 10-3 mm2/s |
| Joo, 2015 | 3T | QL | 0, 100, 500, and 1000 | Two radiologists (in consensus) | Axial GRE-3D-T1W, HASTE-T2W, True-FISP, DWI | SAD ≥ 8 mm or any LN with higher signal intensity than muscle on DWI with b values of 500 or 10002/sec |
| Zhou, 2014 | 3T | QN | 0, 1000 | Two radiologists (independently) | TSE-T2WI without fat suppression, SS-SE-EP DWI with fat suppression. | ADC value < 1.189 × 10-3mm2/s |
| Lei, 2013 | 1.5T | QL | 600 | ND | Cross-sectional and coronal oblique T1 FSPGR, T2 SSFSE, T2 ASSET, DWI | SAD of perigastric LN > 5 mm and distalis perigastric LN > 6 mm |
Abbreviations: QL = qualitative; QN = quantitative; SAD = short-axis diameter; LN =lymph node; MRI = magnetic resonance imaging; DWI = diffusion weighted imaging; T1WI = T1 weighted imaging; T2WI = T2 weighted imaging; ADC = apparent diffusion coefficient; SE = Spin echo; TSE = turbo spin-echo; SPGR = spoiled gradient recalled echo; SS-SE-EP = single-shot spin-echo echo-planar imaging; GRE = gradient recalled echo; HASTE = half-fourier acquisition single-shot turbo spin-echo; True-FISP = true fast imaging with steady-state precession; FLASH = fast low angle shot; SSFSE = single-shot fast spin-echo; ASSET = array spatial sensitivity encoding technique; FSPGR = fast spoiled gradient-recalled; ND = not documented.