Left Atrial Appendage Thrombus Detected During Hyperacute Stroke Imaging Is Associated With Atrial Fibrillation.

BACKGROUND AND PURPOSE: Left atrial appendage (LAA) is the likely embolic source in atrial fibrillation (AF)-related cardioembolic strokes. We sought to determine the prevalence of LAA thrombus on hyperacute stroke imaging and its association with AF. METHODS: We retrospectively examined the clinical and radiological features of patients assessed through the hyperacute stroke imaging pathway over a 12-month period at Christchurch Hospital. The LAA was included in the computed tomography angiogram scan-range as part of the multimodal imaging protocol. Two radiological readers blinded to clinical information independently assessed for the presence of LAA thrombus. The association between AF and LAA thrombus was determined by multivariable logistic regression analysis. RESULTS: Of 303 patients included in the analysis, the overall prevalence of LAA thrombus was 6.6% and 14.9% in patients with known AF. Patients with LAA thrombus were older (85 versus 75 years, P<0.01), more commonly had known or newly diagnosed AF (75% versus 30%, P<0.01) and heart failure (30% versus 8%, P=0.01), and was associated with intracranial large vessel occlusion (65% versus 39%, P=0.02). In the multivariable model, AF (odds ratio, 3.71 [95% CI, 1.25-11.01] P=0.02) was independently associated with LAA thrombus after adjusting for age and congestive heart failure. Interrater reliability was moderate (kappa=0.56). CONCLUSIONS: LAA thrombus is a potential radiological marker of AF and can be assessed as a part of hyperacute stroke imaging.

A Hybrid 2D/3D User Interface for Radiological Diagnosis.

This paper presents a novel 2D/3D desktop virtual reality hybrid user interface for radiology that focuses on improving 3D manipulation required in some diagnostic tasks. An evaluation of our system revealed that our hybrid interface is more efficient for novice users and more accurate for both novice and experienced users when compared to traditional 2D only interfaces. This is a significant finding because it indicates, as the techniques mature, that hybrid interfaces can provide significant benefit to image evaluation. Our hybrid system combines a zSpace stereoscopic display with 2D displays, and mouse and keyboard input. It allows the use of 2D and 3D components interchangeably, or simultaneously. The system was evaluated against a 2D only interface with a user study that involved performing a scoliosis diagnosis task. There were two user groups: medical students and radiology residents. We found improvements in completion time for medical students, and in accuracy for both groups. In particular, the accuracy of medical students improved to match that of the residents.

Axial: an abused word?

OBJECTIVE: This article will discuss how the word axial has developed into a synonym for transverse, and why this is incorrect usage when describing an anatomic plane. CONCLUSION: Radiologists should be aware of what these terms mean and use them appropriately. Journal editors are in a unique position to encourage this.