Technology and Simulation to Improve Patient Safety.

Improving the quality and efficiency of surgical techniques, reducing technical errors in the operating suite, and ultimately improving patient safety and outcomes through education are common goals in all surgical specialties. Current surgical simulation programs represent an effort to enhance and optimize the training experience, to overcome the training limitations of a mandated 80-hour work week, and have the overall goal of providing a well-balanced resident education in a society with a decreasing level of tolerance for medical errors

Does location matter? Characterisation of the anatomic locations, molecular profiles, and clinical features of gliomas

Background. Neuroanatomic locations of gliomas may influence clinical presentations, molecular profiles, and patients’ prognoses. Methods. We investigated our institutional cancer registry to include patients with glioma over a 10-year period. Statistical tests were used to compare demographic, genetic, and clinical characteristics among patients with gliomas in different locations. Survival analysis methods were then used to assess associations between location and overall survival in the full cohort, as well as in relevant subgroups. Results. 182 gliomas were identified. Of the tumours confined to a single lobe, there were 51 frontal (28.0%), 50 temporal (27.5%), 22 parietal (12.1%), and seven occipital tumours (3.8%) identified. Tumours affecting the temporal lobe were associated with reduced overall survival when compared to all other tumours (11 months vs. 13 months, log-rank p = 0.0068). In subgroup analyses, this result was significant for males [HR (95%CI) 2.05 (1.30, 3.24), p = 0.002], but not for females [HR (95%CI) 1.12 (0.65, 1.93), p = 0.691]. Out of 82 cases tested for IDH-1, 10 were mutated (5.5%). IDH-1 mutation was present in six frontal, two temporal, one thalamic, and one multifocal tumour. Out of 21 cases tested for 1p19q deletions, 12 were co-deleted, nine of which were frontal lobe tumours. MGMT methylation was assessed in 45 cases; 7/14 frontal tumours and 6/13 temporal tumours were methylated. Conclusion. Our results support the hypothesis that the anatomical locations of gliomas influence patients’ clinical courses. Temporal lobe tumours were associated with poorer survival, though this association appeared to be driven by these patients’ more aggressive tumour profiles and higher risk baseline demographics. Independently, female patients who had temporal lobe tumours fared better than males. Molecular analysis was limited by the low prevalence of genetic testing in the study sample, highlighting the importance of capturing this information for all gliomas. Importance of this study. The specific neuroanatomic location of tumours in the brain is thought to be predictive of treatment options and overall prognosis. Despite evidence for the clinical significance of this information, there is relatively little information available regarding the incidence and prevalence of tumours in the different anatomical regions of the brain. This study has more fully characterised tumour prevalence in different regions of the brain. Additionally, we have analysed how this information may affect tumours’ molecular characteristics, treatment options offered to patients, and patients’ overall survival. This information will be informative both in the clinical setting and in directing future research

Quantifying intra-tumoral genetic heterogeneity of glioblastoma toward precision medicine using MRI and a data-inclusive machine learning algorithm

Glioblastoma (GBM) is one of the most aggressive and lethal human cancers. Intra-tumoral genetic heterogeneity poses a significant challenge for treatment. Biopsy is invasive, which motivates the development of non-invasive, MRI-based machine learning (ML) models to quantify intra-tumoral genetic heterogeneity for each patient. This capability holds great promise for enabling better therapeutic selection to improve patient outcomes. We proposed a novel Weakly Supervised Ordinal Support Vector Machine (WSO-SVM) to predict regional genetic alteration status within each GBM tumor using MRI. WSO-SVM was applied to a unique dataset of 318 image-localized biopsies with spatially matched multiparametric MRI from 74 GBM patients. The model was trained to predict the regional genetic alteration of three GBM driver genes (EGFR, PDGFRA, and PTEN) based on features extracted from the corresponding region of five MRI contrast images. For comparison, a variety of existing ML algorithms were also applied. The classification accuracy of each gene was compared between the different algorithms. The SHapley Additive exPlanations (SHAP) method was further applied to compute contribution scores of different contrast images. Finally, the trained WSO-SVM was used to generate prediction maps within the tumoral area of each patient to help visualize the intra-tumoral genetic heterogeneity. This study demonstrated the feasibility of using MRI and WSO-SVM to enable non-invasive prediction of intra-tumoral regional genetic alteration for each GBM patient, which can inform future adaptive therapies for individualized oncology.Comment: 36 pages, 8 figures, 3 table

Intraventricular Hemorrhage Secondary to Intranidal Aneurysm Rupture—Successful Management by Arteriovenous Malformation Embolization Followed by Intraventricular Tissue Plasminogen Activator: Case Report

Background And Importance: Intraventricular hemorrhage related to arteriovenous malformation (AVM) rupture is associated with significant morbidity and mortality. Intraventricular tissue plasminogen activator (tPA) has been used to treat spontaneous intraventricular hemorrhage. We demonstrate the successful application of endovascular occlusion to seal the rupture site of an AVM followed by intraventricular tPA. Clinical Presentation: A 32-year-old woman presented with a right frontoparietal parasagittal AVM abutting the motor cortex. The AVM was diagnosed when the patient was 13 years old, and she initially underwent conservative management. At the age of 30, the patient suffered an intracranial hemorrhage, leaving her with left hemiparesis. After rehabilitation, the patient regained ambulation; however, she remained spastic and hyperreflexic on the left side. Two years after her major hemorrhage, she presented for elective treatment of her AVM. The patient was advised to undergo staged embolization before surgical resection of her AVM. The initial embolization was uneventful. A second embolization was complicated by intraventricular hemorrhage and coma. The patient was treated with placement of an external ventricular drain followed by embolization of intranidal aneurysm. After embolization of the intranidal aneurysm the ruptured, the patient was treated with intraventricular tPA. The patient had rapid clearance of the intraventricular hemorrhage and significant improvement in her neurological examination, following commands 24 hours later and returning almost to baseline. Conclusion: This case demonstrates the feasibility of treating AVM-related intraventricular hemorrhage with tPA if the rupture source can be confidently sealed interventionally. This strategy can be lifesaving but needs further study to ensure its safety

Midterm clinical experience with a complex-shaped detachable platinum coil system for the treatment of cerebral aneurysms: Trufill DCS Orbit detachable coil system registry interim results

PURPOSE: To report an interim analysis of the registry data and evaluate the performance of Trufill DCS Orbit coils in terms of the stability of initial aneurysmal occlusion. MATERIALS AND METHODS: From May 1, 2004, to February 1, 2006, 291 patients with ruptured or unruptured aneurysms were enrolled in a multiple-center global registry from 37 centers in the United States, Europe, and Latin America to be treated via endovascular embolization with Trufill DCS Orbit detachable platinum coils. Acute and long-term anatomic and clinical data were collected and evaluated. RESULTS: Initially, complete obliteration was reported in 187 of 300 treated aneurysms (62.3%) for which data were available; one treated aneurysm had no initial occlusion data. At follow-up (<= 1 year), 99 aneurysms were assessed. For 56 aneurysms with initial complete obliteration, 49 (87.5%) remained stable. The overall grade of occlusion of 99 aneurysms remained stable or improved in 81 cases (81.8%). Recanalization was seen in 16.2% of aneurysms (15 cases of coil compaction and one case of aneurysm growth); two aneurysms (2.0%) had coil migration. Five aneurysms (5.1%) underwent repeat treatment. CONCLUSIONS: The use of Trufill DCS Orbit coils for the endovascular occlusion of aneurysms allowed a favorable rate of initial complete obliteration, high packing density, and aneurysmal stability at follow-up as long as 1 year. Longer-term follow-up is needed to determine the long-term stability of aneurysmal occlusion