Sinonasal organizing hematomas are rare lesions of the paranasal sinuses whose clinical characteristics lead to misdiagnoses of benign or malignant neoplasms. Endoscopy, preoperative biopsy, and computed tomography (CT) imaging do not lend helpful information in differentiating these lesions from more worrisome neoplastic processes. However, MRI can lead to positive diagnosis by recognizing the distinct outer rims of T2 hypointensity typically seen in these lesions.

Posterior epistaxis is a significant medical problem that can be challenging to treat. Endoscopic surgery could potentially reduced operative time and patient risk; however, surgeons report difficulty in endoscopically isolating the major offending artery, the sphenopalatine. These difficulties could be reduced if a recognizable anatomic structure marked the region of the artery. The study objective is to characterize the relationship of a relatively unknown anatomic structure, the crista ethmoidalis, to the sphenopalatine foramen/artery, in an effort to facilitate location of the sphenopalatine artery during endoscopic ligation. Using 22 human cadaveric sagitally sectioned heads and standard gross anatomic dissection techniques, the presence of the crista ethmoidalis was sought and recorded as well as its relative location to the sphenopalatine foramen/artery. The crista ethmoidalis was present and closely related to the sphenopalatine foramen and artery in all specimens. In 21/22 specimens, the crista was located just anterior to the sphenopalatine foramen, whereas in one specimen it was located 3 mm directly inferior to the foramen. Our investigation indicates that the crista ethmoidalis is a helpful and reliable landmark for endoscopically locating the sphenopalatine artery and foramen. Using this landmark, the initial problems reported with endoscopic ligation, i.e., locating the foramen and artery, should be greatly reduced. We offer our observations regarding the crista ethmoidalis to assist endoscopic surgeons in the care of their difficult epistaxis patients.

This study presents the application of a simplex active surface model featuring weak shape priors for 3D segmentation of healthy as well as herniated discs. A framework was developed that enables the application of shape priors in the healthy part of disc anatomy, with user intervention when the priors were inapplicable. The surface-mesh-based segmentation method is part of a processing pipeline for anatomical modelling to support interactive surgery simulation.

Background and Purpose Previous univariate analyses have suggested that proximal middle cerebral artery (MCA) infarcts with insular involvement have greater severity, and are more likely to progress into surrounding penumbral “tissue-at-risk”. We hypothesized that a practical, simple scoring method to assess percent insular-ribbon infarction (“PIRI-score”) would improve prediction of penumbral-loss over other common imaging biomarkers. Methods Of consecutive acute stroke patients from 2003–2008, forty-five with proximal-MCA-only occlusion met inclusion criteria, including available penumbral imaging. Infarct (DWI), tissue-at-risk (MR-MTT), and final infarct-volume (MR/CT) were manually segmented. DWI images were rated according to the 5-point PIRI-score (“0”=normal, “1”<25%, “2”=25–49%, “3”=50–74%, and “4”≥75% insula involvement). Percent-mismatch-loss (PML) was calculated as an outcome measure of infarct progression. ROC and multivariate analyses were performed. Results Mean admission DWI-infarct-volume was 30.9 (±38.8) ml, and median (IQR) PIRI-score was 3 (0.75–4). PIRI-score was significantly correlated with PML (p<0.0001). When PML was dichotomized based on its median value (30.0%), ROC-AUC (area-under-curve) was 0.89 (p=0.0001) with a 25% insula-infarction optimal-threshold. After adjusting for time-to-imaging and treatment, binary-logistic regression, including dichotomized PIRI (25% threshold), age, NIHSS-score, DWI-infarct-volume, and CTA-collateral-score as covariates, revealed that only dichotomized insula-score (p=0.03) and age (p=0.02) were independent predictors of large (68.2%) vs. small (8.1%) mismatch-loss. There was excellent inter-observer agreement for dichotomized PIRI-scoring (κ =0.91). Conclusions Admission insular infarction >25% is the strongest predictor of large mismatch-loss in this cohort of proximal-MCA occlusive stroke. This outcome marker may help to identify treatment-eligible patients who are in greatest need of rapid reperfusion therapy.