Lessons Learned with Enhanced Recovery for Open Abdominal Aortic Aneurysm Surgery: A Long Term Regional Network Experience.

OBJECTIVE: This enhanced recovery programme (ERP) aimed to achieve early recovery for patients undergoing major surgery. Results of a standardised ERP protocol for open infrarenal abdominal aortic aneurysm (AAA) repair within a hub and spoke regional network are presented. METHODS: In this single centre prospective study (January 2004 - December 2021), consecutive AAAs (≥ 55 mm) were included in the ERP (patient discharge on post-operative day [POD] 4). The four phases of the ERP were pre-admission, pre-operative, intra-operative, and post-operative. Exclusion criteria were BMI > 35 kg/m2, functional capacity < 4 MET, previous aortic or abdominal surgery, and life expectancy < 5 years. Transperitoneal surgery was undertaken with routine AAA resection, graft interposition, and closure. RESULTS: Consecutive patients (n = 778) were enrolled into the study (mean age 72.3 ± 3.2 years; n = 712 men); 160 (20.5%) were treated in spoke hospitals. Median follow up was 78 (IQR 28, 128) months; median length of stay, procedure time, and blood loss were four days (IQR 3, 5), 190 minutes (IQR 170, 225), and 564 mL (IQR 300, 600). Infrarenal clamping and tube graft configuration were used in 96.5% (n = 751) and 72.5% (n = 564) of patients; 30 day mortality and complication rates were 0.4% (n = 3) and 9.2% (n = 72). Discharge after POD 4 occurred in 15.0%, and most significant predictors for discharge after POD 4 were blood transfusion, re-intervention, and ileus over three days. Overall survival was: 98.2% at one year, 85.0% at five years, and 59.9% at 10 years. Freedom from re-intervention was 97.9% at one year, 94.1% at five years, and 86.8% at 10 years. Short and long term outcomes were comparable between hub and spoke hospitals. CONCLUSION: The ERP protocol was associated with low short and long term mortality and complication rates. Future studies should apply the ERP protocol in other vascular centres.

Deep learning-based localization algorithms on fluorescence human brain 3D reconstruction: a comparative study using stereology as a reference.

3D reconstruction of human brain volumes at high resolution is now possible thanks to advancements in tissue clearing methods and fluorescence microscopy techniques. Analyzing the massive data produced with these approaches requires automatic methods able to perform fast and accurate cell counting and localization. Recent advances in deep learning have enabled the development of various tools for cell segmentation. However, accurate quantification of neurons in the human brain presents specific challenges, such as high pixel intensity variability, autofluorescence, non-specific fluorescence and very large size of data. In this paper, we provide a thorough empirical evaluation of three techniques based on deep learning (StarDist, CellPose and BCFind-v2, an updated version of BCFind) using a recently introduced three-dimensional stereological design as a reference for large-scale insights. As a representative problem in human brain analysis, we focus on a 4 -cm 3 portion of the Broca's area. We aim at helping users in selecting appropriate techniques depending on their research objectives. To this end, we compare methods along various dimensions of analysis, including correctness of the predicted density and localization, computational efficiency, and human annotation effort. Our results suggest that deep learning approaches are very effective, have a high throughput providing each cell 3D location, and obtain results comparable to the estimates of the adopted stereological design.

Brain-wide neuron quantification toolkit reveals strong sexual dimorphism in the evolution of fear memory.

Fear responses are functionally adaptive behaviors that are strengthened as memories. Indeed, detailed knowledge of the neural circuitry modulating fear memory could be the turning point for the comprehension of this emotion and its pathological states. A comprehensive understanding of the circuits mediating memory encoding, consolidation, and retrieval presents the fundamental technological challenge of analyzing activity in the entire brain with single-neuron resolution. In this context, we develop the brain-wide neuron quantification toolkit (BRANT) for mapping whole-brain neuronal activation at micron-scale resolution, combining tissue clearing, high-resolution light-sheet microscopy, and automated image analysis. The robustness and scalability of this method allow us to quantify the evolution of activity patterns across multiple phases of memory in mice. This approach highlights a strong sexual dimorphism in recruited circuits, which has no counterpart in the behavior. The methodology presented here paves the way for a comprehensive characterization of the evolution of fear memory.

Hearing outcomes and patient satisfaction after stapes surgery: local versus general anaesthesia.

Objective: Otosclerosis is a frequent ear disorder causing a stapedo-ovalar ankylosis and conductive hearing loss. Stapedoplasty, performed under both general (GA) and local anaesthesia (LA), is the most advisable surgical solution. Auditory recovery relies on the patient's conditions and on the intervention itself. The aim of our work was to compare hearing outcomes with stapedoplasty performed under GA or LA and to investigate patients' compliance to both methods. Methods: Fifty-five otosclerotic patients underwent stapedoplasty both under GA (32/55) and LA (23/55). Pre- and post-operative air and bone tone audiometry threshold values as well as the air-bone gap and its closure score, were analysed. All patients filled in a satisfaction questionnaire regarding their concern and level of appreciation of the type of anaesthesia. Results and conclusions: Our data show that the auditory results with stapedoplasty are good and do not differ between LA and GA. Even considering the advantages and limits of the two methods, one cannot favour one or the other type of anaesthesia. Finally, the patient's satisfaction cannot be considered a criterion of choice, since this was found to be high in both cases.

Latency correction in sparse neuronal spike trains.

BACKGROUND: In neurophysiological data, latency refers to a global shift of spikes from one spike train to the next, either caused by response onset fluctuations or by finite propagation speed. Such systematic shifts in spike timing lead to a spurious decrease in synchrony which needs to be corrected. NEW METHOD: We propose a new algorithm of multivariate latency correction suitable for sparse data for which the relevant information is not primarily in the rate but in the timing of each individual spike. The algorithm is designed to correct systematic delays while maintaining all other kinds of noisy disturbances. It consists of two steps, spike matching and distance minimization between the matched spikes using simulated annealing. RESULTS: We show its effectiveness on simulated and real data: cortical propagation patterns recorded via calcium imaging from mice before and after stroke. Using simulations of these data we also establish criteria that can be evaluated beforehand in order to anticipate whether our algorithm is likely to yield a considerable improvement for a given dataset. COMPARISON WITH EXISTING METHOD(S): Existing methods of latency correction rely on adjusting peaks in rate profiles, an approach that is not feasible for spike trains with low firing in which the timing of individual spikes contains essential information. CONCLUSIONS: For any given dataset the criterion for applicability of the algorithm can be evaluated quickly and in case of a positive outcome the latency correction can be applied easily since the source codes of the algorithm are publicly available.

Cortical propagation tracks functional recovery after stroke.

Stroke is a debilitating condition affecting millions of people worldwide. The development of improved rehabilitation therapies rests on finding biomarkers suitable for tracking functional damage and recovery. To achieve this goal, we perform a spatiotemporal analysis of cortical activity obtained by wide-field calcium images in mice before and after stroke. We compare spontaneous recovery with three different post-stroke rehabilitation paradigms, motor training alone, pharmacological contralesional inactivation and both combined. We identify three novel indicators that are able to track how movement-evoked global activation patterns are impaired by stroke and evolve during rehabilitation: the duration, the smoothness, and the angle of individual propagation events. Results show that, compared to pre-stroke conditions, propagation of cortical activity in the subacute phase right after stroke is slowed down and more irregular. When comparing rehabilitation paradigms, we find that mice treated with both motor training and pharmacological intervention, the only group associated with generalized recovery, manifest new propagation patterns, that are even faster and smoother than before the stroke. In conclusion, our new spatiotemporal propagation indicators could represent promising biomarkers that are able to uncover neural correlates not only of motor deficits caused by stroke but also of functional recovery during rehabilitation. In turn, these insights could pave the way towards more targeted post-stroke therapies.

Congruous Torsional Down Beating Nystagmus in the Third Position of the Semont's Maneuver in Patients Treated for Canalithiasis of Posterior Semicircular Canal Benign Paroxysmal Positional Vertigo: Its Significance and Prognostic Value.

Due to its mechanical pathogenesis, benign paroxysmal positional vertigo treatment is mainly physical: when posterior semicircular canal is involved, Semont's maneuver is reported as one of the most effective liberating procedures. In the case of a canalolithiasis, the efficacy of the maneuver is corroborated by the appearance of some nystagmus findings during its performance. Liberating nystagmus, that can occur in the second position of Semont's maneuver and whose direction is congruous with the excitation of the affected posterior semicircular canal has proven to be a favorable prognostic sign. On the other hand, in clinical experience, we've frequently verified the appearance of another nystagmus during the execution of the maneuver: upon reaching the third position, when replacing the patient seated, a torsional down beating nystagmus, with the torsional component "congruous" with the stimulation of the vertical semicircular canals of the affected side, can often be appreciated. Such a sign can occur with or without having had the previous liberating nystagmus in the second position and is almost always associated with an intense vertigo and/or body pulsion. In this study, we describe the incidence and characteristics of the congruous torsional down beating nystagmus that can arise by assuming the third position of Semont's maneuver in a cohort of patients treated for posterior semicircular canal benign paroxysmal positional vertigo due to canalolithiasis. In the best of our knowledge, such a sign has never been described and explained before. On the basis of the pathophysiology and of the possible canal receptors stimulation during the different phases of Semont's maneuver, we formulated different hypothesis on how such a nystagmus can be generated. We observed that such a sign, when elicited, has a very good prognostic meaning for healing purposes, even better than that of liberating nystagmus. Therefore, congruous torsional down beating nystagmus should always be checked when performing Semont's maneuver because it could help in predicting success of physical treatment and in managing patients.