Predictive value of pre-treatment apparent diffusion coefficient (ADC) in radio-chemiotherapy treated head and neck squamous cell carcinoma.

OBJECTIVE: This study aimed at evaluating the role of "baseline" apparent diffusion coefficent (ADC), in patients affected by head and neck cancer treated with radio-chemotherapy, as a potential marker of response to therapy. METHODS: Fifty-seven patients underwent pretreatment ADC maps. Minimum, maximum, and medium ADC were computed. Age, dose, treatment time, and ADC values were compared between the two groups (Group 1: local control; Group 2: relapse/persistence of disease) using the Student t test two-tailed unpaired. Two-tailed Fischer exact test was used to compare T stage, N stage, grading and type of treatment between two groups. We have analyzed the receiver operating characteristic (ROC) of statistically significant variables. RESULTS: In patients with local control, values of pre-treatment medium and minimum ADC were lower than ADC values of patients with persistent or recurrent disease, with values, respectively, of 0.83 ± 0.02 × 10-3 mm2/s and 0.59 ± 0.02 × 10-3 mm2/s (vs 0.94 ± 0.05 × 10-3 mm2/s and 0.70 ± 0.05 × 10-3 mm2/s). ROC curve analysis displayed statistical significance as regarding the medium ADC value, showing a sensitivity of 50% and a specificity of 84.8%. ROC analysis of the values minimum ADC showed a sensitivity of 42.9% and specificity of 87.9%. CONCLUSION: The value of the ADC pre-treatment of patients with local control of the disease is lower than that of patients with persistent disease or recurrence.

MRI can assess glenoid bone loss after shoulder luxation: inter- and intra-individual comparison with CT.

OBJECTIVE: Computed tomography (CT) is the gold standard for evaluating glenoid bone loss in patients with glenohumeral dislocations. The aim of this study was to verify if magnetic resonance imaging (MRI) can quantify the area of bone loss without any significant difference from CT. MATERIALS AND METHODS: Twenty-three patients, who had experienced one or more post-traumatic unilateral glenohumeral dislocations, underwent MRI and CT. MR and multiplanar reconstruction CT images were acquired in the sagittal plane: the glenoid area and the area of bone loss were calculated using the PICO method. Mean values, percentages, Cohen's kappa coefficients and Bland-Altman plots were all used to confirm the working hypothesis. RESULTS: The mean glenoid surface area was 575.29 mm(2) as measured by MRI, and 573.76 mm(2) as measured by CT; the calculated mean glenoid bone loss was respectively 4.38% and 4.34%. The interobserver agreement was good (k>0.81), and the coefficient of variance was 5% of the mean value using both methods. The two series of measurements were within two standard deviations of each other. CONCLUSIONS: MRI is a valid alternative to CT for measuring glenoid bone loss in patients with glenohumeral dislocation.