Functional brain imaging interventions for radiation therapy planning in patients with glioblastoma: a systematic review.

RATIONALE: This systematic review aims to synthesise the outcomes of different strategies of incorporating functional biological markers in the radiation therapy plans of patients with glioblastoma to support clinicians and further research. METHODS: The systematic review protocol was registered on PROSPERO (CRD42021221021). A structured search for publications was performed following PRISMA guidelines. Quality assessment was performed using the Newcastle-Ottawa Scale. Study characteristics, intervention methodology and outcomes were extracted using Covidence. Data analysis focused on radiation therapy target volumes, toxicity, dose distributions, recurrence and survival mapped to functional image-guided radiotherapy interventions. RESULTS: There were 5733 citations screened, with 53 citations (n = 32 studies) meeting review criteria. Studies compared standard radiation therapy planning volumes with functional image-derived volumes (n = 20 studies), treated radiation therapy volumes with recurrences (n = 15 studies), the impact on current standard target delineations (n = 9 studies), treated functional volumes and survival (n = 8 studies), functionally guided dose escalation (n = 8 studies), radiomics (n = 4 studies) and optimal organ at risk sparing (n = 3 studies). The approaches to target outlining and dose escalation were heterogeneous. The analysis indicated an improvement in median overall survival of over two months compared with a historical control group. Simultaneous-integrated-boost dose escalation of 72-76 Gy in 30 fractions appeared to have an acceptable toxicity profile when delivered with inverse planning to a volume smaller than 100 cm[Formula: see text]. CONCLUSION: There was significant heterogeneity between the approaches taken by different study groups when implementing functional image-guided radiotherapy. It is recommended that functional imaging data be incorporated into the gross tumour volume with appropriate technology-specific margins used to create the clinical target volume when designing radiation therapy plans for patients with glioblastoma.

Is the iPad suitable for image display at American Board of Radiology examinations?

OBJECTIVE: The study aimed to determine the acceptability of the iPad 3 as a display option for American Board of Radiology (ABR) examinations. SUBJECTS AND METHODS: A set of 20 cases for each of nine specialties examined by the ABR was prepared. Each comprised between one and seven images and case information and had been used in previous ABR Initial Certification examinations. Examining radiologists (n = 119) at the ABR oral Initial Certification examinations reviewed sets from one or more specialties on both a 2 MP LED monitor and on the iPad 3 and rated the visibility of the salient image features for each case. The Wilcoxon signed rank test was performed to compare ratings. In addition, a thematic analysis of participants' opinions was undertaken. RESULTS: When all specialties were pooled, the iPad 3 ratings were significantly higher than the monitor ratings (p = 0.0217). The breast, gastrointestinal, genitourinary, and nuclear medicine specialties also returned significantly higher ratings for the visibility of relevant image features for the iPad 3. Monitor ratings were significantly higher for the vascular and interventional specialty, although no images were rated unacceptably poor on the iPad in this specialty. CONCLUSION: The relevant image features were rated more visible on the iPad 3 than on the monitors overall. The iPad 3 was well accepted by a large majority of examiners and can be considered adequate for image display for examination in most or all specialties.

Flexible image evaluation: iPad versus secondary-class monitors for review of MR spinal emergency cases, a comparative study.

RATIONALE AND OBJECTIVES: Studies have highlighted the potential of handheld viewing devices for rapid diagnosis and increased smartphone usage among physicians and radiologists is known as is the clinical applicability of hand-held devices for computed tomography (CT) spinal injury cases. Magnetic resonance (MR), however, is the accepted gold standard for spinal imaging, providing visualization of both ligament and spinal cord pathology. This study investigated the diagnostic accuracy of the iPad, the most probable alternative display device outside the radiology environment and financially viable alternative, when reviewing emergency spinal MR images, in comparison with secondary-class LCD devices in the case of the interpretation of CT and MR imaging examinations. MATERIALS AND METHODS: In total 31 MR cases including both positives (n = 13) containing one of four possible presentations: spinal cord compression, cauda equine syndrome, spinal cord hemorrhage, or spinal cord edema and controls (n = 18) were reviewed. Ziltron iPad software facilitated the display of cases and the receiver operating characteristic (ROC) analysis. Thirteen American Board of Radiology board-certified radiologists reviewed all cases on both displays. Standardized viewing conditions were maintained. RESULTS: Dorfman-Berbaum-Metz multireader-multicase (DBM MRMC) analysis was performed including random readers/random cases, fixed readers/random cases and random readers/fixed cases. No differences of statistical significance (P ≤ .05) could be found in terms of area under the curve, sensitivity and specificity between the iPad and secondary-class display. CONCLUSION: The iPad performed with equal diagnostic accuracy when compared with the secondary-class LCD device after DBM MRMC analysis, demonstrating the iPad as an option to aid initial review of MR spinal emergency cases.

The "memory effect" for repeated radiologic observations.

OBJECTIVE: It is assumed that memory has a role to play in repeated radiologic observation studies. The main objective of this study was to examine this assumption and evaluate the effect that memory may have on receiver operating characteristic (ROC) methods. MATERIALS AND METHODS: A two-center observer study was performed with a total of 24 experienced radiologists. Over two viewings, chest radiographs showing the tip of a central line in either the superior vena cava or the azygos vein were presented. Half of the images were changed between the two viewings. The participants' attention was directed on the first reading to the position of the central line. At the second reading, the participants were asked to assign a confidence score on a 6-point scale about whether each image had been included in the first reading. RESULTS: For the images that were scored as "definitely included" in the first viewing, readers at our two centers recalled only an average of 2.5 and 4.9 of the 20 repeated images, which is close to a random allocation of images to each score. As the confidence levels diminished for positive identification of repeated images, the numbers of correct answers increased. For images scored as not having been previously included, the numbers of correct answers remained low suggesting that identification of nonrepeated images is poor. Images with a greater number of incidental abnormalities and with more striking abnormalities were recognized more accurately than those with fewer and less striking abnormalities. CONCLUSION: This study shows a "memory effect" when the same images are presented at a second viewing within a small interval period. This effect appears to occur mainly at low confidence levels. These results suggest that including images with obvious incidental abnormalities in reader performance studies should be avoided.

The effect of abnormality-prevalence expectation on expert observer performance and visual search.

PURPOSE: To measure the effect of abnormality-prevalence expectation on experienced radiologists' performance during pulmonary nodular lesion detection on a chest radiograph. MATERIALS AND METHODS: A multiobserver receiver operating characteristic (ROC) and eye-position analysis study was performed to assess the effect of prevalence expectation on observer performance. Twenty-two experienced radiologists were divided into three groups and each was asked to interpret 30 (15 abnormal) identical posteroanterior chest images twice and decide if pulmonary lesions were present. Before each viewing, the radiologists were told that the images contained a specific number of abnormal images: group 1: 9 and 15; group 2: 15 and 22; and group 3: 15 and not told. RESULTS: ROC analysis demonstrated that no significant effect could be measured as a function of prevalence expectation (P > .05). However, eye-position analysis showed significant increases in eye movements at higher prevalence expectation rates in terms of the number of fixations per image (group 1: P = .0001; group 2: P = .0001; group 3: P = .001) and the total scrutiny time of each image (group 1: P = .0001; group 2: P = .0283; group 3: P = .028). CONCLUSION: Overall, findings of this study showed no evidence that the accuracy of expert radiologists is altered due to changing prevalence expectation rates. However, the time spent interpreting each image and the number of fixations increased at higher prevalence rates. Maintenance of diagnostic efficacy has been shown even when circumstances challenge normal observer behavior.

Diagnostic efficacy of handheld devices for emergency radiologic consultation.

OBJECTIVE: Orthopedic injury and intracranial hemorrhage are commonly encountered in emergency radiology, and accurate and timely diagnosis is important. The purpose of this study was to determine whether the diagnostic accuracy of handheld computing devices is comparable to that of monitors that might be used in emergency teleconsultation. SUBJECTS AND METHODS: Two handheld devices, a Dell Axim personal digital assistant (PDA) and an Apple iPod Touch device, were studied. The diagnostic efficacy of each device was tested against that of secondary-class monitors (primary class being clinical workstation display) for each of two image types-posteroanterior wrist radiographs and slices from CT of the brain-yielding four separate observer performance studies. Participants read a bank of 30 wrist or brain images searching for a specific abnormality (distal radial fracture, fresh intracranial bleed) and rated their confidence in their decisions. A total of 168 readings by examining radiologists of the American Board of Radiology were gathered, and the results were subjected to receiver operating characteristics analysis. RESULTS: In the PDA brain CT study, the scores of PDA readings were significantly higher than those of monitor readings for all observers (p < or = 0.01) and for radiologists who were not neuroradiology specialists (p < or = 0.05). No statistically significant differences between handheld device and monitor findings were found for the PDA wrist images or in the iPod Touch device studies, although some comparisons approached significance. CONCLUSION: Handheld devices show promise in the field of emergency teleconsultation for detection of basic orthopedic injuries and intracranial hemorrhage. Further investigation is warranted.