Utilizing Grasp Monitoring to Predict Microsurgical Expertise.

INTRODUCTION: Most microsurgical procedures require the surgeon to use tools to grasp and hold fragile objects in the surgical site. Prior research on grasping in surgery has mostly either been in other surgical techniques or used grasping as an auxiliary metric. We focus on microsurgery and investigate what grasping can tell about microsurgical skill and suturing performance. This study lays groundwork for using automatic detection of grasps to evaluate surgical skill. METHODS: Five expert surgeons and six novices completed sutures on a microsurgical training board. Video recordings of the performance were annotated for the number of grasps, while an eye tracker recorded the participants' pupil dilations for cognitive workload assessment. Performance was measured with suturing duration and the University of Western Ontario Microsurgical Skills Assessment instrument (UWOMSA). Differences in skill, suturing performance and cognitive workload were compared with grasping behavior. RESULTS: Novices needed significantly more grasps to complete sutures and failed to grasp more often than the experts. The number of grasps affected the suturing duration more in novices. Decreasing suturing efficiency as measured by UWOMSA instrument was associated with increase in grasps, even when we controlled for overall skill differences. Novices displayed larger pupil dilations when averaged over a sufficiently large sample, and the difference increased after the grasp. CONCLUSIONS: Grasping action during microsurgical procedures can be used as a conceptually simple yet objective proxy in microsurgical performance assessment. If the grasps could be detected automatically, they could be used to aid in computational evaluation of surgical trainees' performance.

Endoscopic third ventriculostomy for adults with hydrocephalus: creating a prognostic model for success: protocol for a retrospective multicentre study (Nordic ETV).

INTRODUCTION: Endoscopic third ventriculostomy (ETV) is becoming an increasingly widespread treatment for hydrocephalus, but research is primarily based on paediatric populations. In 2009, Kulkarni et al created the ETV Success score to predict the outcome of ETV in children. The purpose of this study is to create a prognostic model to predict the success of ETV for adult patients with hydrocephalus. The ability to predict who will benefit from an ETV will allow better primary patient selection both for ETV and shunting. This would reduce additional second procedures due to primary treatment failure. A success score specific for adults could also be used as a communication tool to provide better information and guidance to patients. METHODS AND ANALYSIS: The study will adhere to the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis reporting guidelines and conducted as a retrospective chart review of all patients≥18 years of age treated with ETV at the participating centres between 1 January 2010 and 31 December 2018. Data collection is conducted locally in a standardised database. Univariate analysis will be used to identify several strong predictors to be included in a multivariate logistic regression model. The model will be validated using K-fold cross validation. Discrimination will be assessed using area under the receiver operating characteristic curve (AUROC) and calibration with calibration belt plots. ETHICS AND DISSEMINATION: The study is approved by appropriate ethics or patient safety boards in all participating countries. TRIAL REGISTRATION NUMBER: NCT04773938; Pre-results.

Eye-Tracking Indicators of Workload in Surgery: A Systematic Review.

BackgroundEye tracking is a powerful tool for unobtrusive and real time assessment of workload in clinical settings. Before the complex eye tracking derived surrogates can be proactively utilized to improve surgical safety, the indications, validity and reliability requires careful evaluation.MethodsWe conducted a systematic review of literature from 2010 to 2020 according to PRISMA guidelines. A search on PubMed, Cochrane, Scopus, Web of science, PsycInfo and Google scholar databases was conducted on July 2020. The following search query was used" ("eye tracking" OR "gaze tracking") AND (surgery OR surgical OR operative OR intraoperative) AND (workload OR stress)". Short papers, no peer reviewed or papers in which eye-tracking methodology was not used to investigate workload or stress factors in surgery, were omitted.ResultsA total of 17 (N = 17) studies were identified eligible to this review. Most of the studies (n = 15) measured workload in simulated setting. Task difficulty and expertise were the most studied factors. Studies consistently showed surgeon's eye movements such as pupil responses, gaze patterns, blinks were associated with the level of perceived workload. However, differences between measurements in operational room and simulated environments have been found.ConclusionPupil responses, blink rate and gaze indices are valid indicators of workload. However, the effect of distractions and non-technical factors on workload is underrepresented aspect in the literature even though recognized as underlying factors in successful surgery.

Automated tool detection with deep learning for monitoring kinematics and eye-hand coordination in microsurgery.

In microsurgical procedures, surgeons use micro-instruments under high magnifications to handle delicate tissues. These procedures require highly skilled attentional and motor control for planning and implementing eye-hand coordination strategies. Eye-hand coordination in surgery has mostly been studied in open, laparoscopic, and robot-assisted surgeries, as there are no available tools to perform automatic tool detection in microsurgery. We introduce and investigate a method for simultaneous detection and processing of micro-instruments and gaze during microsurgery. We train and evaluate a convolutional neural network for detecting 17 microsurgical tools with a dataset of 7500 frames from 20 videos of simulated and real surgical procedures. Model evaluations result in mean average precision at the 0.5 threshold of 89.5-91.4% for validation and 69.7-73.2% for testing over partially unseen surgical settings, and the average inference time of 39.90 ± 1.2 frames/second. While prior research has mostly evaluated surgical tool detection on homogeneous datasets with limited number of tools, we demonstrate the feasibility of transfer learning, and conclude that detectors that generalize reliably to new settings require data from several different surgical procedures. In a case study, we apply the detector with a microscope eye tracker to investigate tool use and eye-hand coordination during an intracranial vessel dissection task. The results show that tool kinematics differentiate microsurgical actions. The gaze-to-microscissors distances are also smaller during dissection than other actions when the surgeon has more space to maneuver. The presented detection pipeline provides the clinical and research communities with a valuable resource for automatic content extraction and objective skill assessment in various microsurgical environments.

Movement-level process modeling of microsurgical bimanual and unimanual tasks.

PURPOSE: Microsurgical techniques require highly skilled manual handling of specialized surgical instruments. Surgical process models are central for objective evaluation of these skills, enabling data-driven solutions that can improve intraoperative efficiency. METHOD: We built a surgical process model, defined at movement level in terms of elementary surgical actions ([Formula: see text]) and targets ([Formula: see text]). The model also included nonproductive movements, which enabled us to evaluate suturing efficiency and bi-manual dexterity. The elementary activities were used to investigate differences between novice ([Formula: see text]) and expert surgeons ([Formula: see text]) by comparing the cosine similarity of vector representations of a microsurgical suturing training task and its different segments. RESULTS: Based on our model, the experts were significantly more efficient than the novices at using their tools individually and simultaneously. At suture level, the experts were significantly more efficient at using their left hand tool, but the differences were not significant for the right hand tool. At the level of individual suture segments, the experts had on average 21.0 % higher suturing efficiency and 48.2 % higher bi-manual efficiency, and the results varied between segments. Similarity of the manual actions showed that expert and novice surgeons could be distinguished by their movement patterns. CONCLUSIONS: The surgical process model allowed us to identify differences between novices' and experts' movements and to evaluate their uni- and bi-manual tool use efficiency. Analyzing surgical tasks in this manner could be used to evaluate surgical skill and help surgical trainees detect problems in their performance computationally.

Rat subthalamic stimulation: Evaluating stimulation-induced dyskinesias, choosing stimulation currents and evaluating the anti-akinetic effect in the cylinder test.

In experimental deep brain stimulation of the subthalamic nucleus (STN HFS), stimulation currents just below the appearance threshold of stimulation-induced dyskinesias has often been used. The behavioral effect of STN HFS can be measured by the reversal of forelimb use asymmetry produced by hemiparkinsonism can be measured with the cylinder test among other tests. We used 18 Wistar rats with 6-hydroxydopamine induced hemiparkinsonism to test a customized scale to rate the severity of stimulation-induced dyskinesia; we then used these ratings to choose low and high stimulation currents. Subsequent cylinder tests showed that stimulation at the higher current, inducing mild and short-lived dyskinesias, was required for robust improvement in forelimb use, contradicting the use of currents below stimulation-induced dyskinesia threshold. It was also beneficial to separately count both all touches and first touches with the cylinder wall; this provided additional sensitivity and robustness to our results. •Scoring stimulation-induced dyskinesias can be used as a quantitative measure of dyskinesias and to choose stimulation currents.•Cylinder test scoring separately for both first and all touches can improve both sensitivity and reliability.•STN HFS at a current producing short-lived dyskinesias was required for robust improvement in forelimb use asymmetry.

Laitinen's Subgenual Cingulotomy: Anatomical Location and Case Report.

BACKGROUND: The widespread use of deep brain stimulation (DBS) for movement disorders has renewed the interest in DBS for psychiatric disorders. Lauri Laitinen was a pioneer of stereotactic psychosurgery in the 1950s to 1970s, especially by introducing the subgenual cingulotomy. Our aim here was to verify the anatomical target used by Laitinen, to report on a patient who underwent this procedure, and to review the literature. MATERIALS AND METHODS: The records of Helsinki University Hospital were searched for psychosurgical cases performed between 1970 and 1974. Alive consenting patients were interviewed and underwent a brain MRI. RESULTS: We found 1 patient alive who underwent subgenual cingulotomy in 1971 for obsessive thoughts, anxiety, and compulsions, diagnosed at that time as "schizophrenia psychoneurotica." MRI showed bilateral subgenual cingulotomy lesions (254 and 160 mm3, respectively). The coordinates of the center of the lesions in relation to the midcommissural point for the right and left, respectively, were: 7.1 and 7.9 mm lateral; 0.2 mm inferior and 1.4 mm superior, and 33.0 and 33.9 anterior, confirming correct subgenual targeting. The patient reported retrospective satisfactory results. CONCLUSIONS: The lesion in this patient was found to be in the expected location, which gives some verification of the correct placement of Laitinen's subgenus cingulotomy target.

Motor outcome and electrode location in deep brain stimulation in Parkinson's disease.

OBJECTIVES: To evaluate the efficacy and adverse effects of subthalamic deep brain stimulation (STN-DBS) in patients with advanced Parkinson's disease (PD) and the possible correlation between electrode location and clinical outcome. METHODS: We retrospectively reviewed 87 PD-related STN-DBS operations at Helsinki University Hospital (HUH) from 2007 to 2014. The changes of Unified Parkinson's Disease Rating Scale (UPDRS) part III score, Hoehn & Yahr stage, antiparkinson medication, and adverse effects were studied. We estimated the active electrode location in three different coordinate systems: direct visual analysis of MRI correlated to brain atlas, location in relation to the nucleus borders and location in relation to the midcommisural point. RESULTS: At 6 months after operation, both levodopa equivalent doses (LEDs; 35%, Wilcoxon signed-rank test = 0.000) and UPDRS part III scores significantly decreased (38%, Wilcoxon signed-rank test = 0.000). Four patients (5%) suffered from moderate DBS-related dysarthria. The generator and electrodes had to be removed in one patient due to infection (1%). Electrode coordinates in the three coordinate systems correlated well with each other. On the left side, more ventral location of the active contact was associated with greater LED decrease. CONCLUSIONS: STN-DBS improves motor function and enables the reduction in antiparkinson medication with an acceptable adverse effect profile. More ventral location of the active contact may allow stronger LED reduction. Further research on the correlation between contact location, clinical outcome, and LED reduction is warranted.

The impact of neurosurgical procedure on cognitive resources: Results of bypass training.

BACKGROUND: Neurosurgeons are exposed to unavoidable distractions in their natural operating environment. Distractions can affect both the surgeon's concentration and the safety and duration of the surgery. Such distraction can be studied by applying a simultaneous cognitive task during a surgical procedure. METHODS: We used a previously described cognitive task: a forward (DF) and backward digit (DB) repetition task to interfere with the surgeon's attention during a training bypass. A pilot study was performed to find suitable digit repetition lengths. For the main experiment, we used four-digit strings. The test task was alternated across two consecutive sutures (n = 153, 8 bypasses), followed by two consecutive control sutures without digit repetition. The duration and the number of correct answers for the digit repetition task were compared to a baseline digit repetition without simultaneous surgery. RESULTS: During the bypass surgery, digit repetitions (especially DB) became slower (P < 0.0001). More errors were made during DB compared to DF only during simultaneous bypass (P < 0.0001). However, we found no effect of digit repetition tasks on individual suture times (P = 0.823). CONCLUSIONS: The ability to engage in simultaneous tasks while performing surgery is diminished. A surgeon with extensive training can withstand external distraction without an effect on performance; however, this is achieved by partially ignoring the simultaneous task. Our data support that during surgery other cognitive tasks should be avoided to ensure safety.

Combination of CDNF and Deep Brain Stimulation Decreases Neurological Deficits in Late-stage Model Parkinson's Disease.

Several neurotrophic factors (NTF) are shown to be neuroprotective and neurorestorative in pre-clinical animal models for Parkinson's disease (PD), particularly in models where striatal dopamine neuron innervation partially exists. The results of clinical trials on late-stage patients have been modest. Subthalamic deep brain stimulation (STN DBS) is a proven treatment for a selected group of advanced PD patients. The cerebral dopamine neurotrophic factor (CDNF) is a promising therapeutic protein, but its effects in animal models of late-stage PD have remained under-researched. The interactions of NTF and STN DBS treatments have not been studied before. We found that a nigral CDNF protein alone had only a marginal effect on the behavioral deficits in a late-stage hemiparkinsonian rat model (6-OHDA MFB). However, CDNF improved the effect of acute STN DBS on front limb use asymmetry at 2 and 3 weeks after CDNF injection. STN lesion-modeling chronic stimulation-had an additive effect in reducing front limb use in the cylinder test and apomorphine-induced rotation. The combination of CDNF and acute STN DBS had a favorable effect on striatal tyrosine hydroxylase. This study presents a novel additive beneficial effect of NTF and STN DBS, which might be explained by the interaction of DBS-induced endogenous NTFs and exogenously injected CDNF. SNpc can be reached via similar trajectories used in clinical STN DBS, and this interaction is an important area for future studies.

Easy, Efficient, and Mobile Way to Train Microsurgical Skills During Busy Life of Neurosurgical Residency in Resource-Challenged Environment.

BACKGROUND: Residents' lives are hectic-it is hard to find a place and time for training basic and advanced microsurgical skills. Surgical instruments and sutures can be purchased (or loaned from another department), but the most expensive and space-occupying device is the microscope. In developing countries, microscopes are used where they are needed most, in operating rooms. Furthermore, a conventional microscope is not portable. For all of these reasons, the availability of microscopes for training microsurgery is limited. METHOD: We used a coffee cup and smartphone (CCS) as a training device instead of a microscope. The coffee cup was the base, and the smartphone functioned to magnify, illuminate, and visualize objects. We measured 2 residents' performance on end-to-end artificial bypass before and after 5 days of CCS-based training. RESULTS: We were able to quickly set up the environment for practicing microsurgical skills in any surrounding. After 5 days of training with CCS we could see significant development of microsurgical performance with a conventional microscope as well. The learning curve was dependent on baseline performance. CONCLUSION: CCS is efficient, mobile, and easy to set up. Even though our smartphone-based training was in 2 dimensions, we could improve our microsurgical performance with conventional microscopes, which have 3-dimensional capability. CCS also provides an easy method to record one's microsurgical training. CCS improved both of the subjects' microsurgical performance, making it a good alternative for a traditional microscope.

STN DBS for Advanced Parkinson Disease Simultaneously Alleviates Cluster Headache.

BACKGROUND: STB DBS (deep brain stimulation of the subthalamic nucleus) is commonly used to treat advanced Parkinson disease (PD) while posterior hypothalamic DBS for cluster headache (CH) remains experimental. METHODS: We present a case where a middle-aged man was diagnosed with both CH and PD and received medical treatment for both. The patient was treated with bilateral STN DBS after developing side effects related to L-dopa. FINDINGS: STN DBS not only alleviated PD symptoms but also the CH, and hence the CH treatment could be withdrawn. During follow-up PD progressed but the effect on CH symptoms was sustained. CONCLUSIONS: The anatomical proximity of the medial STN and hypothalamus, their similar connectivity via the hyperdirect pathway, and the autonomic effects of STN DBS could explain symptom relief for both PD and CH.

Serotonin transporter in attention-deficit hyperactivity disorder--preliminary results from a positron emission tomography study.

The serotonin transporter (SERT) in attention-deficit hyperactivity disorder (ADHD) patients has not been explored by earlier positron emission tomography (PET) studies. We measured SERT availability in female ADHD patients (n=8) and healthy controls (n=14) with PET and [11C]MADAM as a tracer. No significant group differences in [11C]MADAM binding potential were noted.