| Literature DB >> 29949036 |
Walaa Alsharif1,2, Michaela Davis3, Louise Rainford3, Andrea Cradock3, Allison McGee3.
Abstract
AIM: The aim was to design an app-based eLearning tool to provide radiographers with information about the physical basis of MR artefacts and practical elimination or/and minimisation strategies to optimise image quality, and to evaluate the impact of a smartphone app on radiographers' knowledge.Entities:
Keywords: App; Confidence; Image quality; Knowledge; MRI
Year: 2018 PMID: 29949036 PMCID: PMC6206384 DOI: 10.1007/s13244-018-0635-0
Source DB: PubMed Journal: Insights Imaging ISSN: 1869-4101
Fig. 1A screen shot of the app logo
Fig. 2A screen shot of the app contents page
Fig. 3A screen shot showing a sample of the app content
Questions used in the image experiment to evaluate radiographers’ knowledge with regard to MR image-quality errors
| Questions | |
|---|---|
| A- Indicate if an artefact and/or other technical error is present within an MR image |
Demographic profile of the participants
| Group | Hospital Type | Years of Experience | Qualification | |||||
|---|---|---|---|---|---|---|---|---|
| Public | Military | Academic | 1-5 | 6+ | Diploma | Degree | ||
| Pre-test | 13 | 13 | 9 | 21 | 14 | 8 | 27 | |
| Post-test | Experimental | 6 | 6 | 4 | 9 | 7 | 4 | 12 |
| Control | 7 | 7 | 5 | 12 | 7 | 4 | 15 | |
The percentage of images within the MR image dataset
| Image | Frequency | Percentage |
|---|---|---|
| SNR (Signal to noise ratio) | 4 | 16% |
| CNR (Contrast to noise ratio) | 6 | 24% |
| SR (Spatial resolution) | 2 | 8% |
| Artefact | 7 | 28% |
| SNR and CNR | 1 | 4% |
| No quality errors evident | 5 | 20% |
| Total | 25 | 100% |
Variations in radiographer responses to the recognition of MR image-quality errors
| Error Category | Group | Number of images | Total Number of responses | Number (%) correct (pre-test) | Number (%) Dis-improved | Number (%) incorrect (pre-test) | Number (%) improved |
|---|---|---|---|---|---|---|---|
| Image without errors | Control Group | 5 | 80 | 61 (76.3%) | 8 (12.9%) | 19 (23.8%) | 8 (42.1%) |
| Experimental Group | 95 | 86 (90%) | 9 (12.3%) | 22 (23.2%) | 19 (86.4%) | ||
| Image with errors | Control Group | 20 | 320 | 314 (98.1%) | 6 (2.1%) | 39 (12.2%) | 4 (10.3%) |
| Experimental Group | 380 | 375 (98.7%) | 5 (1.5%) | 37 (9.7%) | 34 (91.9%) |
Variations in radiographer responses in identifying different types of MR image-quality errors
| Error Category | Group Control N = 16 Experimental N = 19 | Number of images | Total Number of responses | Number (%) correct (pre-test) | Number (%) Dis-improved | Number (%) incorrect (pre-test) | Number (%) improved |
|---|---|---|---|---|---|---|---|
| SNR (Signal to noise ratio) | Control | 4 | 64 | 40 (62.5%) | 7 (16.3%) | 24 (37.5%) | 6 (25%) |
| Experimental | 76 | 44 (57.9%) | 15 (34.1%) | 32 (42.1%) | 18 (56.3%) | ||
| CNR (Contrast to noise ratio) | Control | 6 | 96 | 67 (69.8%) | 10 (15.9%) | 29 (30.2%) | 7 (24.1%) |
| Experimental | 114 | 65 (57.02%) | 0 (0%) | 49 (43%) | 40 (81.6%) | ||
| SR (Spatial resolution) | Control | 2 | 32 | 11 (34.4%) | 3 (27.2%) | 21 (65.6%) | 4 (19%) |
| Experimental | 38 | 17 (44.7%) | 0 (0%) | 21 (55.3%) | 21 (100%) | ||
| Artefact | Control | 7 | 112 | 51 (45.5%) | 4 (7.8%) | 61 (54.5%) | 4 (6.6%) |
| Experimental | 133 | 74 (55.6%) | 3 (4.1%) | 59 (44.4%) | 37 (62.7%) | ||
| No Technical Error Evident | Control | 5 | 80 | 62 (77.5%) | 7 (11.3%) | 18 (22.5%) | 6 (33.3%) |
| Experimental | 95 | 73 (76.9%) | 7 (9.6%) | 22 (23.2%) | 19 (86.4%) | ||
| SNR and CNR | Control | 1 | 16 | 10 (62.5%) | 2 (20%) | 6 (37.5%) | 0 (0%) |
| Experimental | 19 | 15 (78.9%) | 0 (0%) | 4 (21.1%) | 4 (100%) |
Variation in radiographer responses in specifying the appropriate error-correction strategy for MR image-quality errors
| Correction Strategy | Group Control N = 16 Experimental N = 19 | Number of images | Total Number of responses | Number (%) correct (pre-test) | Number (%) Dis-improved | Number (%) incorrect (pre-test) | Number (%) improved |
|---|---|---|---|---|---|---|---|
| Change Sequence parameters | Control | 4 | 64 | 15 (23.4%) | 4 (26.7%) | 49 (76.6%) | 5 (10.2%) |
| Experimental | 76 | 17 (22.4%) | 1 (5.9%) | 59 (77.6%) | 42 (71.2%) | ||
| Patient setup issue | Control | 2 | 32 | 19 (59.4%) | 5 (26.3%) | 13 (40.6%) | 1 (7.7%) |
| Experimental | 38 | 28 (73.7%) | 0 (0%) | 10 (26.3%) | 8 (80%) | ||
| Change timing parameters | Control | 3 | 48 | 19 (39.6%) | 4 (21.1%) | 29 (60.4%) | 2 (6.9%) |
| Experimental | 57 | 22 (38.6%) | 0 (0%) | 35 (61.4%) | 34 (97.1%) | ||
| Artefact | Control | 3 | 48 | 24 (50%) | 3 (12.5%) | 24 (50%) | 2 (8.3%) |
| Experimental | 57 | 27 (47.4%) | 1 (3.7%) | 30 (52.6%) | 19 (63.3%) | ||
| Correct RF coil | Control | 3 | 48 | 12 (25%) | 4 (33.3%) | 36 (75%) | 5 (13.9%) |
| Experimental | 57 | 18 (31.6%) | 6 (33.3%) | 39 (68.4%) | 16 (41%) | ||
| Change scanning technique | Control | 5 | 80 | 19 (23.8%) | 5 (26.3%) | 61 (76.3%) | 3 (4.9%) |
| Experimental | 95 | 23 (24.2%) | 3 (13%) | 72 (75.8%) | 56 (77.8%) | ||
| No technical error evident | Control | 5 | 80 | 62 (77.5%) | 6 (9.7%) | 18 (22.5%) | 6 (33.3%) |
| Experimental | 95 | 73 (76.9%) | 7 (9.6%) | 22 (23.2%) | 19 (86.4%) |
A table demonstrating the confidence level in identifying the type of the image quality errors and specifying an appropriate error-correction strategy for both groups
| Pre-test confidence level | Post-test confidence level | Change in confidence level | |||
|---|---|---|---|---|---|
| Confidence level in identifying the type of the image quality errors | Group | Valid N | Median (1RQ) | Median (IRQ) | Median (IRQ) |
| Control | 16 | 90 (80-100) | 90 (80-100) | 0 (0-0) | |
| Experimental | 19 | 90 (80-100) | 85 (80-85) | 0 (−5-0) | |
| Confidence level in specifying the error-correction strategy | Control | 16 | 80 (72-95) | 80 (80-98) | 0 (0-0) |
| Experimental | 19 | 85 (75-90) | 80 (80-85) | 0 (−5-5) | |
A table demonstrating a multiple linear regression used to evaluate the impact of the app on radiographers’ knowledge
| Model | Unstandardised Coefficients | Standardised Coefficients | t | 95.0% Confidence Interval for B | R square | ||||
|---|---|---|---|---|---|---|---|---|---|
| B | Std. Error | Beta | Lower Bound | Upper Bound | |||||
| Recognise the existence of the image quality errors | Intercept | 11.502 | 2.782 | 4.134 | <0.001 | 5.835 | 17.169 | 0.57 | |
| Access to the app | 2.460 | 0.443 | 0.651 | 5.556 | <0.001 | 1.558 | 3.362 | ||
| Pre-test | −.544 | 0.129 | −.493 | −4.207 | <0.001 | −.807 | −.281 | ||
| Identifying the type of the image quality errors | Intercept | 8.892 | 1.709 | 5.202 | <0.001 | 5.410 | 12.374 | 0.783 | |
| Access to the app | 6.434 | 0.700 | 0.757 | 9.191 | <0.001 | 5.008 | 7.860 | ||
| Pre-test | −.615 | 0.108 | −.469 | −5.686 | <0.001 | −.836 | −.395 | ||
| Specifying the appropriate correction strategy | Intercept | 6.539 | 1.935 | 3.380 | <0.002 | 2.599 | 10.480 | 0.802 | |
| Access to the app | 9.912 | 0.905 | 0.862 | 10.948 | <0.001 | 8.068 | 11.756 | ||
| Pre-test | −.657 | 0.171 | −.302 | −3.841 | <0.001 | −1.005 | −.308 | ||
Fig. 4Scatterplot of median change in confidence level for radiographers in identifying the type of image-quality errors verse pre-test confidence by experimental group
Fig. 5Scatterplot of median change in confidence level for radiographers in specifying the error-correction strategy of image-quality errors verse pre-test confidence by experimental group
A table demonstrating a multiple linear regression used to evaluate the impact of the app on radiographers’ level of confidence in reviewing MR image quality
| Model | Unstandardised Coefficients | Standardised Coefficients | t | p-value | 95.0% Confidence Interval for B | R square | |||
|---|---|---|---|---|---|---|---|---|---|
| B | Std. Error | Beta | Lower Bound | Upper Bound | |||||
| Confidence level in identifying the type of the image quality errors | Intercept | 22.267 | 3.603 | 3.295 | <0.002 | 8.502 | 36.032 | 0.231 | |
| Access to the App | −.876 | 1.696 | −.078 | −.516 | 0.609 | −4.331 | 2.579 | ||
| Pre-test | −.258 | 0.075 | −.519 | −3.447 | <.002 | 0.410 | −.106 | ||
| Confidence level in specifying the appropriate correct strategy | Intercept | 35.856 | 6.587 | 5.443 | <0.001 | 224.38 | 49.274 | 0.454 | |
| Access to the App | 0.790 | 2.035 | 0.049 | 0.378 | 0.700 | −3.355 | 3.238 | ||
| Pre-test | −.770 | 0.078 | −.696 | −5.492 | <0.001 | −.590 | −.271 | ||