Learning curves in radiological reporting of whole-body MRI in plasma cell disease: a retrospective study.

BACKGROUND: The plasma cell disease is been studying by the whole-body MRI technology. However, the time requested to learn this radiological technique is unknown. PURPOSE: To esteem, quantitatively and qualitatively, the essential time to learn the whole-body MRI diffusion-weighted imaging with background body signal suppression in patients with plasma cell disease. MATERIALS AND METHODS: Between January 2015 and February 2017, three readers in-training with different levels of experience examined the anonymised and randomised whole-body MRI images of 52 patients with a diagnosis of plasma cell disease and analysed their morphological (T1w, T2w with and without fat suppression) and functional sequences. Reports of an expert radiologist were considered the standard of reference. Images were analysed in two sessions, during which each reader was timed. Readers reported the number of segments with lesions and staged the disease using the Durie-Salmon PLUS staging system. Weighted Cohen's ĸ and Z-test were used to compare the trainees' reports with those of the expert radiologist, and learning curves were drawn up to show changes between the two sessions. RESULTS: Weighted Cohen's ĸ of number of lesioned segments increased from 0.536 ± 0.123 to 0.831 ± 0.129 (Prob > Z under 0.005), thus approaching the goal of ĸ > 0.8. Trainees reached the level of experienced radiologist in terms of time by the 33rd patient. Agreement concerning the Durie-Salmon PLUS increased from 0.536 ± 0.123 to 0.831 ± 0.129 (Prob > Z under 0.005). CONCLUSIONS: The findings of this study demonstrate that whole-body MRI with DWIBS can be learned in about 80 reports and leads to a high level of inter-observer concordance when using the Durie-Salmon PLUS staging system.

Can neuroimaging differentiate PFO and AF-related cardioembolic stroke from the other embolic sources? Clinical-radiological correlation on a retrospective study.

PURPOSE: The aim of this retrospective study was to map the specific ischemic lesion patterns of distribution in patent foramen ovale-related stroke (PFO-stroke) and atrial fibrillation-related stroke (AF-stroke) in patients with idiopatic ischemic stroke. MATERIALS AND METHODS: 750 ischaemic strokes were screened on basis of diagnostic imaging and tests: patients with known causes were excluded. 171 patients with unknown cause were selected and divided in two groups: AF-stroke (43 patients) and PFO-stroke (128 patients). Vascular territories of ischemic involvement were divided into four classes in each group: the anterior cerebral artery, the middle cerebral artery, the vertebro-cerebral artery (including the posterior cerebral artery) and multisite (MS) involvement. RESULTS: Infarcts in vertebro-basilar territory and multisite represented each one about 32% of infarcts in PFO-stroke group and their involvement are more frequent than AF-stroke group (p = 0.03). Ischemic lesions in PFO-group were predominantly cortical (34.3%), and in AF-group cortical-subcortical (60.4%). Multisite pattern of ischemic lesion was more frequent in patients with severe degree of right to left shunts (37.5%). CONCLUSION: In clinical practice, PFO may be considered a cause of cortical stroke on the basis of radiological findings, when VB vascular territory or MS brain involvement is present in younger patients (<50 age).

Comparison of retrospective PET and MRI-DWI (PET/MRI-DWI) image fusion with PET/CT and MRI-DWI in detection of cervical and endometrial cancer lymph node metastases.

OBJECTIVES: The aim of this study was to compare the accuracy of retrospective image fusion of PET/MRI-DWI with that of PET/CT and MRI-DWI alone in detecting metastatic lymph nodes in patients with cervical and endometrial carcinoma. MATERIALS AND METHODS: Twenty-seven patients with endometrial (n = 14) and cervical (n = 13) cancer who had undergone preoperative MRI-DWI and PET/CT for staging were retrospectively evaluated. The accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of PET/CT, MRI-DWI, and PET/MRI-DWI image fusion were calculated on a per-patient basis and on a per-node basis. Histopathological and follow-up imaging results were used as the gold standard. RESULTS: On a per-patient basis PET/MRI-DWI had the same sensitivity (87.5 %), specificity (84.2 %), diagnostic accuracy (85.1 %), PPV (70 %), and NPV (94.1 %) as PET-CT, but on a per-node basis PET/MRI-DWI showed better sensitivity (89 vs 70.2 %), specificity (91.6 vs 90.5 %), diagnostic accuracy (91.2 vs 87 %), PPV (68.7 vs 60.4 %), and NPV (97.6 vs 93.6 %) than PET-CT. Comparison of the areas under the ROC curves for the detection of metastatic lymph nodes demonstrated a non-significant difference (p = 0.055) between PET/CT and fused PET/MRI-DWI. CONCLUSION: PET/MRI-DWI may be a valuable technique for N-staging patients with endometrial and cervical cancer, but more studies are needed to investigate its potential clinical utility.

Combined multimodal co-registration of PET/CT and MRI images increases diagnostic accuracy in squamous cell carcinoma staging.

OBJECTIVES: The purpose of our study was to assess the diagnostic value of multi-modal imaging through co-registration of short tau inversion recovery (STIR) and diffusion-weighted imaging (DWI) MRI with (18)FDG-PET/CT in T and N staging of head and neck tumours. MATERIALS AND METHODS: 25 patients with head and neck squamous cell carcinoma who had undergone MRI and PET/CT before treatment were retrospectively evaluated. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of PET/CT, MRI and their combined use were assessed in T and N staging. Histopathology and follow-up imaging results were used as the gold standard. RESULTS: In assessing trans-compartmental extensions, PET-MRI showed 93 % sensitivity, 88 % specificity, 94 % PPV, and 88 % NPV, as compared to the 94 and 53 % sensitivity, 75 and 75 % specificity, 89 and 82 % PPV, and 86 and 43 % demonstrated by MRI and PET, respectively. In the identification of pathological lymph nodes, PET-MRI showed 92 % sensitivity, 89 % specificity, 96 % PPV, and 89 % NPV, whereas PET/CT displayed 72 % sensitivity, 89 % specificity, 95 % PPV and 53 % NPV. The corresponding figures for DWI and STIR sequences were 84 and 100 % sensitivity, 67 and 56 % specificity, 88 and 86 % PPV, and 60 and 100 % NPV, respectively. CONCLUSIONS: Multi-modal imaging assessment of co-registered MRI and PET/CT images provides more accurate results for trans-compartmental extensions in T and N staging than the individual techniques alone.

Quantitative analysis of cerebrospinal fluid dynamics at phase contrast cine-MRI: predictivity of neurosurgical "Shunt" responsiveness in patients with idiopathic normal pressure hydrocephalus.

BACKGROUND: Aqueductal stroke volume (ACSV) measured by phase-contrast cine (PCC)-MRI has been proposed with controversy as a tool for the selection of patients with normal pressure hydrocephalus (NPH) as candidates for shunt-surgery. The aim of this study was to assess if PCC-MRI scan measurements of ACSV could select properly these patients. METHODS: We retrospectively reviewed charts and MRI of 38 shunted patients (72.16±6.16 years). ACSV measurements were performed 7-30 days before shunt and at the first and sixth months after surgery. Normally distributed variables were compared in the two groups (improved/unimproved) by t-test for baseline values and with repeated measures analysis of variance. RESULTS: Twenty-six patients (68,4%) improved after VPS (mean time of symptom onset was 8.15±7.19 months). Mean preoperative ACSV value was 271.85±143.03, which decreased by 21.6% (mean 213±125.14) at the first month and 40.3% sixth months after VPS (mean 162.15±91.5). Twelve patients (31.6%) did not improve (mean time of symptom onset was 29±5.62 months). Mean preoperative ACSV value was 79.83±31.24, decreased to 8.7% (mean 72.83±28.66) at first month after VPS. 21.2% (mean 62.83±31.12) after six months. We found statistical difference between preoperative ACSV of improved and unimproved patients (P<0.01), onset time of symptoms (P<0.01) and the changes in ACSV after one and six months in both groups (P<0.001). CONCLUSIONS: ACSV is useful to stratify patients with NPH after surgery (improved /not improved) suggesting to proceed with serial ACSV measurements before deciding treatment.