Utility of the novel guide catheter in mechanical thrombectomy for emergent large vessel occlusion stroke.

BACKGROUND: A number of large bore guide catheters are currently available for use in neuroendovascular surgery. This study represents a multi-institutional retrospective series of patients undergoing mechanical thrombectomy with the use of a TracStar Large Distal Platform (LDP) guide catheter and assessed its performance in vivo in 107 patients. OBJECTIVE: To review a multi-institutional initial experience with the TracStar LDP guide catheter during mechanical thrombectomy for emergent large vessel occlusion (ELVO). METHODS: A retrospective review was performed at two level one stroke centres to include all patients who underwent mechanical thrombectomy and had the TracStar LDP guide catheter used during the intervention. RESULTS: The TracStar LDP guide catheter was successfully used in 107 mechanical thrombectomies. In anterior circulation ELVO, the guide catheter advanced into the cavernous segment of the internal carotid artery in 62.6% (62/99) of cases. In posterior circulation cases, the guide catheter advanced to the basilar artery in 87.5% (7/8) of cases. A thrombolysis in cerebral infarction 2b or greater reperfusion was obtained in 90.7% (97/107). No complications occurred related to the TracStar LDP guide catheter. Three complications occurred with aspiration catheters including a small dissection that did not require further intervention and fracturing of the AXS Catalyst 6 catheter tip in two cases. No thromboembolic events occurred. CONCLUSIONS: The TracStar LDP large bore guide catheter is safe and effective at navigating the tortuous vascular anatomy often encountered during mechanical thrombectomy for stroke. The flexible distal and stiffer proximal components provide a good combination of navigability and support for use in neuroendovascular interventions.

Neck CT imaging and correlation with thyroid cancer incidence across age, gender and race.

OBJECTIVE: Incidental detection of thyroid cancers has been proposed as a cause of thyroid cancer increases over past decades, but few studies assess the impact of imaging utilization on thyroid cancer incidence. This study quantifies neck CT prevalence and its relationship with thyroid cancer incidence as a function of age, sex and race. DESIGN AND PATIENTS: Medical records of over 1 million patients at our institution were retrospectively analysed to quantify neck CT prevalence from 2004 to 2011 (study period). A national cancer database was used to compute thyroid cancer incidences over the study period and a reference period (1974-81) and to calculate change in thyroid incidence between the two periods. Both populations were partitioned into demographic subgroups of varying age, sex and race. Linear correlation between neck imaging and thyroid cancer incidence changes among subgroups was assessed using Pearson's correlation. RESULTS: Neck CT imaging and change in thyroid cancer incidence varied across all examined demographic variables, particularly age. When stratifying by age, CT use correlated strongly with recent national thyroid cancer incidence (R = .97) and with 30-year change in thyroid cancer incidence (R = .87). Across all demographic subgroups, CT prevalence correlated strongly and positively with change in thyroid cancer incidence (R = .60), greater for whites (R = .60) and blacks (R = .70) than other races (R = .28). CONCLUSION: Differences in neck CT usage strongly and positively correlates with the variation in thyroid cancer trends based on age, gender and race.

Diagnostic accuracy of MRI texture analysis for grading gliomas.

PURPOSE: Texture analysis (TA) can quantify variations in surface intensity or patterns, including some that are imperceptible to the human visual system. The purpose of this study was to determine the diagnostic accuracy of radiomic based filtration-histogram TA to differentiate high-grade from low-grade gliomas by assessing tumor heterogeneity. METHODS: Patients with a histopathological diagnosis of glioma and preoperative 3T MRI imaging were included in this retrospective study. A region of interest was manually delineated on post-contrast T1 images. TA was performed using commercially available research software. The histogram parameters including mean, standard deviation, entropy, mean of the positive pixels, skewness, and kurtosis were analyzed at spatial scaling factors ranging from 0 to 6 mm. The parameters were correlated with WHO glioma grade using Spearman correlation. Areas under the curve (AUC) were calculated using ROC curve analysis to distinguish tumor grades. RESULTS: Of a total of 94 patients, 14 had low-grade gliomas and 80 had high-grade gliomas. Mean, SD, MPP, entropy and kurtosis each showed significant differences between glioma grades for different spatial scaling filters. Low and high-grade gliomas were best-discriminated using mean of 2 mm fine texture scale, with a sensitivity and specificity of 93% and 86% (AUC of 0.90). CONCLUSIONS: Quantitative measurement of heterogeneity using TA can discriminate high versus low-grade gliomas. Radiomic data of texture features can provide complementary diagnostic information for gliomas.