Quantitative Analysis of Conebeam CT for Delineating Stents in Stent-Assisted Coil Embolization.

BACKGROUND AND PURPOSE: Innovative techniques and device-related advances have improved the outcomes of neuroendovascular treatment. 3D imaging has previously used 2 × 2 binning, but 1 × 1 binning has recently been made available. The aim of this study was to evaluate the quantitative ability of conebeam CT for stent delineation and to investigate its effectiveness in the clinical environment. MATERIALS AND METHODS: Four acquisition groups of 3D MIP images acquired using conebeam CT with varying conditions (acquisition time, 10 or 20 seconds and binning, 1 × 1 or 2 × 2) were compared. Two methods of analysis were performed, a phantom study and an analysis of 28 randomly selected patients. The phantom study assessed the contrast-to-noise ratio and full width at half maximum values in conebeam CT images of intracranial stent struts. In the clinical subjects, we assessed contrast-to-noise ratio, full width at half maximum, and dose-area product. RESULTS: In the phantom study, the contrast-to-noise ratio was not considerably different between 10- and 20-second acquisition times at equivalent binning settings. Additionally, the contrast-to-noise ratio at equivalent acquisition times did not differ considerably by binning setting. For the full width at half maximum results, equivalent acquisition times differed significantly by binning setting. In the clinical analyses, the 10-second/1 × 1 group (versus 20 second/2 × 2) showed a higher contrast-to-noise ratio (P < .05) and a dose-area product reduced by approximately 70% (P < .05), but the difference in full width at half maximum was not significant (P = .20). CONCLUSIONS: For stent-assisted coil embolization, quantitative assessment of conebeam CT showed that 10 second/1 × 1 was equivalent to 20 second/2 × 2 for imaging deployed intracranial stents. Furthermore, the 10-second/1 × 1 settings resulted in a much smaller DAP.

Breast-conserving therapy for ductal carcinoma in situ.

This retrospective analysis evaluates the treatment results and prognostic factors of 114 patients with ductal carcinoma in situ (DCIS) undergoing breast conserving therapy (BCT) at Keio University Hospital Department of Radiology, between 1988 and 1997. A total of 132 patients with DCIS of the breast came to our hospital between 1988 and 1997, and 114 cases were suitable candidates for BCT. All of the patients were female and ranged in age from 26 to 81 years (median 46). Ninety-one patients were premenopausal, and 23 were postmenopausal. Median clinical tumor size was 2.0 cm (0-8.0 cm). Postoperatively 48 cases received 50 Gy/25 fractions of external irradiation to the whole breast via tangential ports. The follow-up period after treatment ranged from 11 to 162 months (median 46.7). The local relapse-free rate and overall survival rate of the 114 patients were 89.5% and 100%, respectively. Local failure and regional nodal failure occurred in 12 and 1 patient, respectively. Radiotherapy was a significant risk factor for local failure (p=0.05). No postmenopausal patients developed local failure, but the difference did not reach statistical significance (p=0.103). The 12 recurrent cases underwent additional surgery and all remain alive without recurrence, to date, i.e., at least 16 months. Breast-conserving surgery plus irradiation is appropriate treatment for DCIS patients.

[Anesthetic management for neonates with congenital cystic adenomatoid malformation].

We experienced two cases of congenital cystic adenomatoid malformation (CCAM) diagnosed by prenatal ultrasonography. The first case with type I CCAM underwent the resection of the right upper lobe 8 days after birth. Postoperative course was uneventful. The second case with type III CCAM developed non-immune hydrops, severe mediastinal shift, and polyhydroamnios at 29 weeks' gestation. At 30 weeks' gestation, cesarean section was performed. Immediately after birth, the resection of lung tumor for the neonate was performed. However, the neonate died on the 1st postoperative day.

[Success rate of anesthesia induction using target-controlled infusion of propofol with fentanyl].

Twenty-one patients were studied to compare the success rate of anesthesia induction using target-controlled infusion of propofol with and without fentanyl. All patients were premedicated with atropine 0.5 mg and hydroxyzine 25-50 mg. Five minutes after intravenous administration of fentanyl 2 micrograms.kg-1, patients were given infusions of propofol designed to achieve target blood concentrations of 3 micrograms.kg-1. Loss of verbal contact was regarded as successful induction. The success rate of anesthesia induction within three minutes of achieving the target concentration was 90%. Pain on injection and reduction in blood pressure were infrequent. Selecting a target concentration of 3 micrograms.kg-1 with fentanyl 2 micrograms.kg-1 can be expected to successfully induce anesthesia in the majority of patients without major hemodynamic side effects and pain on injection.