Computer Assisted Objective Assessment of Micro-Neurosurgical Skills From Intraoperative Videos.

Goal: Conventionally, a surgeon's skill is assessed through visual observation by experts and by tracking patient outcomes. These techniques are very subjective and demands enormous time and effort. Hence, the aim of this study is to construct a framework for automated objective assessment of micro-neurosurgical skill. Methods: A mask region-based convolution neural network (RCNN) is trained to identify and localize instances of surgical instruments from the recorded neurosurgery videos. Then the tool motion and tool handling metrics are computed by tracking the detected instrument locations through time. Microscope adjustment patterns are also investigated via the proposed time based metrics.Results: This study highlights the metrics that could potentially emphasize the variance in expertise between a veteran and a novice. These variations include an expert exhibiting a lower velocity, lower acceleration, lower jerks, reduced path length, higher normalized angular displacement, increased bi-manual handling, shorter idle time and smaller inter tool-tip distances while handling tools accompanied with frequent microscope adjustments and reduced maximum and median intervals between adjustments when compared to a novice. Conclusions: The developed vision based framework has proven to be a reliable method to assess the degree of surgical skill objectively and offer prompt and precise feedback to the neurosurgeons.

Percutaneous intervention for symptomatic vertebral artery stenosis using coronary stents.

BACKGROUND: There is very limited experience with percutaneous treatment of symptomatic vertebral artery disease. Angioplasty and stenting for vertebral artery stenosis are still evolving and have generally been performed for asymptomatic disease. We performed vertebral artery stenting in 12 patients with vertebrobasilar transient ischemic attacks and present our short- and intermediate-term results. METHODS: A total of 12 lesions affecting the vertebral artery were treated by coronary stent placement. The mean age was 72 +/- 8 years and 83% were males (10 males, 2 females). Baseline characteristics included hypertension (11/12); hypercholesterolemia (8/12); coronary artery disease (8/12); and diabetes (5/12). Mean lesion length was 8.6 +/- 2.7 mm, mean calipered stenosis was 78 +/- 8%, and mean arterial diameter was 4.1 +/- 0.3 mm. All patients were symptomatic, fulfilling our criteria for vertebral artery angioplasty. All patients were followed for at least 6 months after treatment. RESULTS: All 12 lesions were successfully stented, with a mean residual stenosis of 11 +/- 6%. Clinical follow-up showed resolution or improvement of symptoms in all patients. One patient had symptomatic restenosis seven months after the initial procedure requiring repeat angioplasty. CONCLUSIONS: Stent placement for symptomatic stenosis involving the vertebral artery is safe and effective for alleviating symptoms of vertebrobasilar ischemia. Coronary stents appear to be well suited to treat atherosclerotic lesions of the vertebral artery.

Self-expanding stents for carotid interventions: comparison of nitinol versus stainless-steel stents.

BACKGROUND: Angioplasty and stenting are becoming increasingly accepted techniques for the treatment of carotid stenosis. However, the optimal stent for carotid intervention is not known. METHODS: We compared the short- and intermediate-term results of carotid stenting using either nitinol or stainless-steel self-expanding stents in 178 high surgical risk patients undergoing carotid stenting at our institution. Of these 178 patients, eighty-nine received stainless-steel stents and 89 received nitinol stents. The groups were similar with respect to age, gender, diabetes, hypertension, left ventricular function, and symptom status. There were more patients with contralateral carotid occlusion in the nitinol stent group. Independent neurological evaluation was performed in all patients pre- and post-carotid stenting. RESULTS: At 6 months, there was a similar incidence of stroke (3.3% versus 2.2%) in the stainless-steel group and nitinol stent group, respectively. There was higher 6-month mortality noted in the stainless-steel stent group, but there were no neurological deaths in either group. CONCLUSIONS: In a single-center patient cohort with similar baseline characteristics, patients receiving nitinol stents and stainless-steel stents had similar neurological outcomes.