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Aim: Aim of this study was to evaluate the Cumulative SUV-volume Histogram as a tool for Magnetic Resonance-guided Focused UltraSound (MRgFUS) treatment monitoring. MRgFUS is an innovative method for metastasis pain palliation and for the related cancerous tissue ablation (in the regions directly accessible to the ultrasound beam). Methods: A patient with pelvic bone metastasis, accessible to the ultrasound beam, was studied by 18F-FDG PET/CT before (I), at 3 (II) and at 6 (III) months after the MRgFUS treatment. At the three different times, the therapy outcome was assessed by: 1) patient interview to obtain the pain perception evaluation (Visual Analog Scale), ranging from 0 to 10, 2) qualitative observation of 18F-FDG PET/CT images, and 3) the target uptake Radiotracer distribution changes. This evaluation was done by using the Cumulative SUV-volume Histograms (CSH) distribution. Similarly to the Dose-Volume Histogram (DVH) distribution in Radiotherapy, the CSH represents the % of tumor metabolic volume that is higher than a SUV threshold, variable from 0 to the maximum SUV value [Van Velden et al, Eur J Nucl Med Mol Imaging,2011 vol.38(9):1636-47]. According to the literature, SUV threshold was set at 50% of maximum SUV and the area under the CSH curve was considered as a quantitative index of the heterogeneity in the FDG uptake inside the lesion volume. The partial volume effect was not considered because the lesion sphere-equivalent diameter was greater than 5 cm. In order to evaluate the ablation effect, the percentage change of CSH was obtained as follows: ?CSH(post vs pre) = 100*(CSHpost - CSHpre)/CSHpre. This value was compared with the patient interview results and with the Nuclear Medicine qualitative assessment. Results: The patient reported a quality-of-life marked improvement, with a pain reduction from 9 (I) to 2 (in II and III). CSH changes in I, II, and III times were observed: ?CSH(II vs I) = -32.7%, ?CSH(III vs II) = -20.4% and ?CSH(III vs I) = -46.4%. These CSH decreases were in agreement with qualitative observation of PET/CT images. Conclusion: In the considered patient, the treatment response along the follow-up stages indicated that MRgFUS therapy was effective in the reduction of the bone metastasis pain and in the ablation of accessible cancerous tissue. CSH showed a marked response in the regions treated with the ultrasound beam and seems to be a useful tool for evaluating the radiotracer uptake heterogeneity in the oncological lesions.

Background: Traditional surgery for uterine fibroids treatments (e.g. myomectomy, hysterectomy) offers very invasive therapeutic approaches, which not always preserve reproductive potential of the woman. MRgFUS (MR guided Focused UltraSound) is a new and non-invasive technique for uterine fibroids treatment, not requiring hospitalization and recovery time [1]. On June 2011 and July 2012 the first treatments were started at HSR-Giglio Hospital in Cefalù and at University Hospital (DIBIMEF) in Palermo. An initial assessment of MRgFUS treatment was made by computing the thermally-ablated volume of uterine fibroid. This volume was evaluated considering the NPV (Non Perfused Volume) on a post-treatment MR dataset acquired with contrast medium. Nowadays, the used approach is a time-expensive and operator-dependent manual segmentation procedure. In this paper, the preliminary results of the two Sicilian facilities are showed and a semi- automatic segmentation approach is proposed, based on multi-seed region-growing technique, to calculate the NPV. The realized approach gives a quantitative evaluation in the post-treatment phase. Materials and Methods: The MRgFUS procedures, regarding women affected by single/multiple uterine fibroid, were performed using the ExAblate 2000 and 2100 (InSightec, Haifa, Israel), which is fully integrated with a 1.5 Tesla MR Scanner (GE Medical System, Milwaukee, WI). For NPV manual and semi-automatic evaluation we have used the sagittal or coronal images acquired after the treatment with a gadolinium-based contrast medium (FSPGR+FS+C protocol). The proposed semi-automatic approach in based on multi-seed region-growing, where it is possible to individualize the processing steps: • pre-processing filtering; • region-growing segmentation; • post-processing filtering; • NPV computation. Results: Among all 23 performed treatments, 69.57% have obtained a NPV, manually evaluated, bigger than 60%, successful treatment threshold, and the 65.22% > 70% and 47.83% > 80%. The evaluation of our segmentation approach was performed by calculating Jaccard and Dice similarity indexes and specificity and sensitivity values. In order to obtain the above indexes, the results of the proposed region-growing approach were compared with the manual segmentation. Preliminary segmentation tests obtained the following results: • Jaccard Index: 87.83%; • Dice Index: 94.12%; • Sensitivity: 91.59%; • Specificity: 89.72%. Conclusion: The MRgFUS provides an important new non-invasive and effective treatment for uterine fibroids. The proposed multi-seed region-growing segmentation approach allows to estimate the NPV in a semi-automatic and operator-independent way. Obtained segmentation indexes show the effectiveness of the implemented technique.

Purpose Anterior cervical spinal surgery with fusion (ACSF) is the most widely used technique in the management of cervical spondylosis or disc herniation. A case of pharyngeal perforation after ACSF demonstrated by videofluorography and MDCT is described. Methods A 39-year-old man, recently undergone to ACSF for interbody C3-C5 fusion with anterior cervical plate and screws, was submitted to a pharingoesophageal videofluorography and 64 row-MDCT of the neck before and after oral administration of iodine contrast medium for persistent high dysphagia. Results In the plain radiograph a fractured screw was detected, anterolaterally displaced on the right to the cervical spine, outside the pharingeal lumen. After high-density (250% weight/volume) barium suspension administration the screw floated outside the pharingeal lumen at C4-C6 level, and an extraluminal leak of barium was observed. On CT MPR and 3D reformatted images confirmed the screw was fractured and displaced outside the plate in the retropharingeal space, anteriorly to C4, and also the hypothesis of posterior pharingeal wall damage, for the presence of gas bubbles in the retropharingeal space, thickening of prevertebral soft tissues, and contrast medium leak through a pharyngeal break in the retropharingeal space. Conclusions Imaging can play a role to correctly address the cause of disphagya after ACSF.

Background The aim of this study was to assess the incidence of the anatomical variations of the sphenoid sinus in 293 patients studied by multidetector computed tomography (MDCT). Materials and Methods The MDCT (64 rows) studies of the paranasal sinuses of 293 patients, performed in 2006-2009, were reviewed to assess anatomical variations of the sphenoid sinus and related neurovascular structures. Anatomical variations were evaluated on 1 mm thick MPR reformations, displayed on a high resolution workstation screen. Pneumatization of the anterior clinoid process (ACP), pterygoid recess (PR), protrusion of the internal carotid artery (ICA), optic nerve (ON), maxillary and vidian nerve into the sphenoid sinus, as well as insertion of sphenoid sinus septa on neurovascular canals were assessed. Onodi cells were also recorded. Results MDCT findings were: pneumatization of the ACP with ON protrusion in 78 patients (26.6%); Onodi cells in 107 patients (36.5%); PR in 83 patients (28%); protrusion of ICA in 107 patients (36%); protrusion of maxillary nerve in 120 patients (40%); protrusion of vidian nerve in 120 patients (40%); sphenoid sinus septa in 34 patients (11.6%); insertion of sphenoid sinus septa on neurovascular canals in 33 patients (11.25%), of whom on optic canal in 2 patients, on carotid canal in 30 patients, on vidian canal in 1 patient; in 1 patient (0.3%) maxillary and vidian nerves protruded in a right Onodi cell that formed a pterygoid recess. Conclusions Preoperative recognition of the anatomical variations by computed tomography is mandatory before FESS, to prevent surgical complications.