Role of non-echo-planar diffusion-weighted images in the identification of recurrent cholesteatoma of the temporal bone.

BACKGROUND AND PURPOSE: The aim of the present prospective study was to verify the specificity of non-EPI DWI-MRI in patients operated for middle ear CHO who showed positivity at imaging performed 6 to 9 months after surgery and underwent second-look surgery. MATERIALS AND METHODS: All patients underwent 1.5-T non-EPI DWI-MRI 6 to 9 months after surgery: those showing a hyper-intense signal in the middle ear underwent a revision surgery, whilst the others are still under radiological follow-up and were not considered in this study. Two radiologists independently evaluated the images; both placed a standard region of interest inside the brightest part of the observed signal alteration on coronal HASTE-DWI images. The mean and maximum signal intensity values on the DWI images were recorded for each patient. A signal intensity ratio was calculated using the inferior temporal cortex and the background noise. RESULTS: One hundred and forty-three subjects were evaluated for a total of 210 ears. In 116 (170 ears), a normal non-EPI DWI-MRI was found with exclusion from this study, whilst twenty-seven subjects showed a high signal lesion inside the middle ear and underwent revision surgery. According to the ROC analysis, SI, SIRT and SIRTmax showed the best statistical values in comparison with the other parameters. CONCLUSIONS: Residual/recurrent CHO can be accurately detected using quantitative evaluation of non-EPI DWI-MRI.

Outcomes of postoperative stereotactic radiosurgery to the resection cavity versus stereotactic radiosurgery alone for melanoma brain metastases.

To investigate local control and radiation-induced brain necrosis in patients with melanoma brain metastases who received complete resection plus fractionated stereotactic radiosurgery (fSRS, 3 × 9 Gy) or fSRS alone. Factors associated with the clinical outcomes and the development of brain necrosis have been assessed. One hundred and twenty consecutive patients with 137 melanoma brain metastases who received surgery plus fSRS (S + fSRS) or fSRS alone were analyzed. All lesions evaluated in the study were treated with a dose of 27 Gy given in 3 fractions over three consecutive days. Cumulative incidence analysis was used to compare local failure (LF), distant brain failure (DBF), and radiation-induced brain necrosis (RN) between groups from the time of SRS. At a median follow-up of 13 months, median OS times and 1-year survival rates were comparable: S + fSRS, 14 months and 85%; fSRS, 12 months and 85% (p = 0.2). Median DBF did not differ significantly by group, being 14 months for both groups. Nine patients who received S + fSRS and 20 patients treated with fSRS recurred locally (p = 0.03). Six-month and 1-year LF rates were 5 and 12% in S + fSRS group and 17 and 28% in fSRS group (p = 0.02). RN occurred in 21 patients (S + fSRS, n = 14; fSRS, n = 7; p = 0.1). The cumulative 1-year incidence of RN was 13% after S + fSRS and 8% after fSRS (p = 0.15). In conclusion, postoperative SRS (3 × 9 Gy) to the resection cavity is an effective treatment modality for melanoma brain metastases associated with better local control as compared with fSRS alone.