A milestone-based approach to breast imaging instruction for residents.

Residency is historically an apprenticeship, learning through observation and instruction with varying degrees of structure. Since July 2013, the Next Accreditation System (NAS) of the ACGME has required the use of progressive milestones for each radiology residency rotation. The authors describe how a breast imaging curriculum can be structured to comply with the NAS. The breast imaging rotations move from basic recognition and management of suspicious findings, through the detection of more subtle findings and learning of biopsy skills, and finally to the synthesis and management of more advanced findings. Likewise, patient communication moves from sharing imaging findings to the more challenging situation of breaking the bad news of a cancer diagnosis. This progression of skills mirrors the objectives of levels 1 to 4 of the NAS. Learning objectives have been adapted to form very specific milestones for each rotation, which results in a shared responsibility between residents and faculty members. Using clear expectations may improve the uniformity of teaching, resident satisfaction, and facilitate performance review for residents who are struggling. Didactic lectures, case-based conferences, teaching file cases, and assigned readings provide different approaches to education, allowing variation in learning styles. Performance on the breast imaging section on the ACR Diagnostic Radiology In-Training examination at our institution has risen from below the 50th percentile to around the 80th percentile beginning in 2011.

Single-center experience with a dual microcatheter technique for the endovascular treatment of wide-necked aneurysms.

OBJECT: The endovascular treatment of wide-necked aneurysms can be technically challenging due to distal coil migration or impingement of the parent vessel. In this paper, the authors illustrate an alternative method for the treatment of wide-necked intracranial aneurysms using a dual microcatheter technique. METHODS: The authors' first 100 consecutive patients who underwent coil embolization of a wide-necked aneurysm using a dual microcatheter technique are reported. With this technique, 2 microcatheters are used to introduce coils into the aneurysm. The coils are deployed either sequentially or concurrently to form a stable construct and prevent coil herniation or migration. Angiographic and clinical outcomes are reported. RESULTS: The technical success rate of the dual microcatheter technique is 91% with a morbidity and mortality of 1% and 2%, respectively. Clinical outcomes are excellent with 93% of patients demonstrating a modified Rankin Scale score of 0-2 at long-term follow-up regardless of their score at presentation. Retreatment rates are 18%. CONCLUSIONS: The dual microcatheter technique may be a safe and efficacious first line of treatment for widenecked aneurysms.

T1-weighted MRI as a substitute to CT for refocusing planning in MR-guided focused ultrasound.

Precise focusing is essential for transcranial MRI-guided focused ultrasound (TcMRgFUS) to minimize collateral damage to non-diseased tissues and to achieve temperatures capable of inducing coagulative necrosis at acceptable power deposition levels. CT is usually used for this refocusing but requires a separate study (CT) ahead of the TcMRgFUS procedure. The goal of this study was to determine whether MRI using an appropriate sequence would be a viable alternative to CT for planning ultrasound refocusing in TcMRgFUS. We tested three MRI pulse sequences (3D T1 weighted 3D volume interpolated breath hold examination (VIBE), proton density weighted 3D sampling perfection with applications optimized contrasts using different flip angle evolution and 3D true fast imaging with steady state precision T2-weighted imaging) on patients who have already had a CT scan performed. We made detailed measurements of the calvarial structure based on the MRI data and compared those so-called 'virtual CT' to detailed measurements of the calvarial structure based on the CT data, used as a reference standard. We then loaded both standard and virtual CT in a TcMRgFUS device and compared the calculated phase correction values, as well as the temperature elevation in a phantom. A series of Bland-Altman measurement agreement analyses showed T1 3D VIBE as the optimal MRI sequence, with respect to minimizing the measurement discrepancy between the MRI derived total skull thickness measurement and the CT derived total skull thickness measurement (mean measurement discrepancy: 0.025; 95% CL (-0.22-0.27); p = 0.825). The T1-weighted sequence was also optimal in estimating skull CT density and skull layer thickness. The mean difference between the phase shifts calculated with the standard CT and the virtual CT reconstructed from the T1 dataset was 0.08 ± 1.2 rad on patients and 0.1 ± 0.9 rad on phantom. Compared to the real CT, the MR-based correction showed a 1 °C drop on the maximum temperature elevation in the phantom (7% relative drop). Without any correction, the maximum temperature was down 6 °C (43% relative drop). We have developed an approach that allows for a reconstruction of a virtual CT dataset from MRI to perform phase correction in TcMRgFUS.