Augmented reality technology shortens aneurysm surgery learning curve for residents

OBJECTIVES

We aimed to prospectively investigate the benefit of using augmented reality (AR) for surgery residents learning aneurysm surgery.

MATERIALS AND METHODS

Eight residents were included, and divided into an AR group and a control group (4 in each group). Both groups were asked to locate an aneurysm with a blue circle on the same screenshot after their viewing of surgery videos from both AR and non-AR tests. Only the AR group was allowed to inspect and manipulate an AR holographic representation of the aneurysm in AR tests. The actual location of the aneurysm was defined by a yellow circle by an attending physician after each test. Localization deviation was determined by the distance between the blue and yellow circle.

RESULTS

Localization deviation was lower in the AR group than in the control group in the last 2 tests (AR Test 2: 2.7 ± 1.0 mm vs. 5.8 ± 4.1 mm, p = 0.01, non-AR Test 2: 2.1 ± 0.8 mm vs. 5.9 ± 5.8 mm, p < 0.001). The mean deviation was lower in non-AR Test 2 as compared to non-AR Test 1 in both groups (AR: p < 0.001, control: p = 0.391). The localization deviation of the AR group decreased from 8.1 ± 3.8 mm in Test 2 to 2.7 ± 1.0 mm in AR Test 2 (p < 0.001).

CONCLUSION

AR technology provides an effective and interactive way for neurosurgery training, and shortens the learning curve for residents in aneurysm surgery.

Complementary role of Indocyanine green video angiography, dual-image video angiography and flow-800

BACKGROUND

Visualization of cerebral vessels, their branches and the surrounding structures are essential during cerebrovascular surgery. Indocyanine green dye-based video angiography is a commonly used technique in cerebrovascular surgery. This paper aims to analyze the real-time imaging of ICG-AG, DIVA, and the use of ICG-VA with Flow 800 to compare their usefulness in surgery.

METHODS

Intraoperative real-time identification of vascular and surrounding structures in twenty nine anterior circulation aneurysms and three posterior circulation aneurysm clipping, one STA-MCA bypass, and two carotid endarterectomies were performed in patients using ICG-VA alone, DIVA, ICG-VA with Flow 800 to analyze and compare each of these methods in details.

RESULTS

ICG-VA and DIVA couldn't visualize perforators in twenty-three cases of cerebral aneurysms clipping when used alone. Compared to that by adding Flow 800 perforators were easily visualized. In three cases, occlusion of perforators after clip application was visualized by DIVA and solved by repositioning surgical clips. In one STA-MCA bypass surgery, adequate blood flow to cortical branches of MCA (M4) from STA branches was assessed with ICG-VA, DIVA, and the use of ICG-VA with Flow 800 color mapping. ICG-VA, DIVA, and Flow 800 observed the lack of blood flow and fluttering atherosclerotic plaques in carotid endarterectomy. In one case of basilar tip aneurysm, we used ICG-VA with Flow 800; the intensity diagram drawn after determining regions of interest showed that there was no flow within the aneurysm sac after clipping.

CONCLUSION

In real-time surgery, a multimodal approach using ICG-VA, DIVA, and ICG-VA with Flow 800 colour mapping can serve as useful tools for better visualization of vascular and surrounding structures. The benefits of flow 800 color mapping, such as determining regions of interest, intensity diagrams, and color-coded images, outweigh the advantages over the ICG-VA and DIVA in the visualization of critical vascular anatomy in humans during surgical procedures.

Randomized study comparing 3D virtual reality and conventional 2D on-screen teaching of cerebrovascular anatomy

OBJECTIVE

Performing aneurysmal clipping requires years of training to successfully understand the 3D neurovascular anatomy. This training has traditionally been obtained by learning through observation. Currently, with fewer operative aneurysm clippings, stricter work-hour regulations, and increased patient safety concerns, novel teaching methods are required for young neurosurgeons. Virtual-reality (VR) models offer the opportunity to either train a specific surgical skill or prepare for an individual surgery. With this study, the authors aimed to compare the spatial orientation between traditional 2D images and 3D VR models in neurosurgical residents or medical students.

METHODS

Residents and students were each randomly assigned to describe 4 aneurysm cases, which could be either 2D images or 3D VR models. The time to aneurysm detection as well as a spatial anatomical description was assessed via an online questionnaire and compared between the groups. The aneurysm cases were 10 selected patient cases treated at the authors' institution.

RESULTS

Overall, the time to aneurysm detection was shorter in the 3D VR model compared to 2D images, with a trend toward statistical significance (25.77 ± 37.26 vs 45.70 ± 51.94 seconds, p = 0.052). No significant difference was observed for residents (3D VR 24.47 ± 40.16 vs 2D 33.52 ± 56.06 seconds, p = 0.564), while in students a significantly shorter time to aneurysm detection was measured using 3D VR models (26.95 ± 35.39 vs 59.16 ± 44.60 seconds, p = 0.015). No significant differences between the modalities for anatomical and descriptive spatial mistakes were observed. Most participants (90%) preferred the 3D VR models for aneurysm detection and description, and only 1 participant (5%) described VR-related side effects such as dizziness or nausea.

CONCLUSIONS

VR platforms facilitate aneurysm recognition and understanding of its spatial anatomy, which could make them the preferred method compared to 2D images in the years to come.

Artificial Neural Network for Predicting the Safe Temporary Artery Occlusion Time in Intracranial Aneurysmal Surgery

BACKGROUND

Temporary artery clipping facilitates safe cerebral aneurysm management, besides a risk for cerebral ischemia. We developed an artificial neural network (ANN) to predict the safe clipping time of temporary artery occlusion (TAO) during intracranial aneurysm surgery.

METHOD

We devised a three-layer model to predict the safe clipping time for TAO. We considered age, the diameter of the right and left middle cerebral arteries (MCAs), the diameter of the right and left A1 segment of anterior cerebral arteries (ACAs), the diameter of the anterior communicating artery, mean velocity of flow at the right and left MCAs, and the mean velocity of flow at the right and left ACAs, as well as the Fisher grading scale of brain CT scans as the input values for the model.

RESULTS

This study included 125 patients: 105 patients from a retrospective cohort for training the model and 20 patients from a prospective cohort for validating the model. The output of the neural network yielded up to 960 s overall safe clipping time for TAO. The input values with the greatest impact on safe TAO were mean velocity of blood at left MCA and left ACA, and Fisher grading scale of brain CT scan.

CONCLUSION

This study presents an axillary framework to improve the accuracy of the estimated safe clipping time interval of temporary artery occlusion in intracranial aneurysm surgery.

Epidemiological Analysis of 5,595 Procedures of Endovascular Correction of Isolated Descending Thoracic Aortic Disease Over 12 Years in the Public Health System in Brazil

OBJECTIVES

In Brazil, descending thoracic aorta disease, including aneurysms and dissections, is managed preferentially by endovascular treatment, owing to its feasibility and good results. In this study, we analyzed endovascular treatment of isolated descending thoracic aortic disease cases in the Brazilian public health system over a 12-year period.

METHODS

Public data from procedures performed from 2008 to 2019 were extracted using web scraping techniques to assess procedure type frequency (elective or urgency), mortality, and governmental costs.

RESULTS

A total of 5,595 procedures were analyzed, the vast majority of which were urgent procedures (61.82% vs. 38.18%). In-hospital mortality was lower for elective than for urgent surgeries (4.96 vs.10.32% p=0.008). An average of R$16,845.86 and R$20,012.04 was paid per elective and emergency procedure, respectively, with no statistical difference (p=0.095).

CONCLUSION

Elective procedures were associated with lower mortality than urgent procedures. There was no statistically significant difference between elective and urgent procedures regarding costs.

Analysis of Sexual Disorders in Men with Infrarenal Abdominal Aortic Aneurysm Treated by Stent-Graft or Prosthesis Implantation-A Pilot Study

Background and objectives: Patients with obstruction or stenosis of the aorta and iliac arteries or with aortic aneurysm, often co-existing with iliac artery aneurysms, suffer from sexual disorders because of insufficient perfusion to the pelvic organs and penis. This is often the cause of visits to a medical doctor's office with reports of a difficult life situation and a problem with the satisfactory completion of sexual intercourse. A low percentage of vascular surgeons or angiologists are prepared to talk about issues related to the hereditary sphere with a patient who qualifies for the treatment of Leriche syndrome or abdominal aortic aneurysm. The aim of this study was to analyze sexual disorders in men with infrarenal abdominal aortic aneurysm treated by stent-graft or prosthesis implantation. Material and methods, Outcomes: 38 patients who completed the IIEF-5 (International Index of Erectile for Men) questionnaire are presented. Initially, 146 qualified for the study after meeting the study inclusion criteria for surgery (Group 1) or for endovascular treatment of abdominal aortic aneurysm (Group 2). Results: In the study, no negative impact of smoking was found; however, over 95% of respondents had been smoking for many years in both groups. Patients who qualified for vascular prosthesis implantation were subject to a more advanced atherosclerotic process involving the aorta and iliac arteries. Patients who qualified for stent-graft implantation were twice as often treated for coronary vessel stenosis. In Group 1, the percentage differences, as shown by questions 1 and 5, were statistically significant (58, i.e., 25%, and 40, i.e., 29%). Conclusions: Education should target medical personnel in terms of conversations with patients, as well as men who are directly affected by this problem, although their partners and families should not be neglected in these activities. The ability to communicate properly allows for an open dialogue on issues that the patient finds difficult, particularly in the field of sexology.

Endoscope- versus microscope-integrated near-infrared indocyanine green videoangiography in aneurysm surgery

OBJECTIVE: The quality of surgical treatment of intracranial aneurysms is determined by complete aneurysm occlusion while preserving blood flow in the parent, branching, and perforating arteries. For a few years, there has been a nearly noninvasive and cost-effective technique for intraoperative flow evaluation: microscope-integrated indocyanine green videoangiography (mICG-VA). This method allows for real-time information about blood flow in the aneurysm and the involved vessels, but its limitations are seen in the evaluation of structures located in the depth of the surgical field, especially through small craniotomies. To compensate for these drawbacks, an endoscope-integrated ICG-VA (eICG-VA) was developed. The objective of the present study was to assess the use of eICG-VA in comparison with mICG-VA for intraoperative blood flow evaluation. METHODS: In the period between January 2011 and January 2015, 216 patients with a total of 248 intracranial saccular aneurysms were surgically treated in the Department of Neurosurgery of Saarland University Medical Center in Homburg/Saar, Germany. During 95 surgeries in 88 patients with a total of 108 aneurysms, intraoperative evaluation was performed with both eICG-VA and mICG-VA. After clipping, evaluation of complete aneurysm occlusion and flow in the parent, branching, and perforating arteries was performed using both methods. Intraoperative applicability of each technique was compared with the other and with postoperative digital subtraction angiography as a standard evaluation technique. RESULTS: Evaluation of completeness of aneurysm occlusion and of flow in the parent, branching, and perforating arteries was more successful with eICG-VA than with mICG-VA, especially for aneurysm neck assessment (88.9% vs 69.4%). For 63.9% of the aneurysms (n = 69), both methods were equivalent, but in 30.6% of the cases (n = 33), the eICG-VA provided better results for evaluating the post-clipping situation. In 4.6% of these aneurysms (n = 5), the information given by the additional endoscope considerably changed the surgical procedure. Thus, one residual aneurysm (0.9%), two neck remnants (1.9%), and two branch occlusions (1.9%) could be prevented. Nevertheless, two incomplete aneurysm occlusions (1.9%) and six neck remnants (5.6%) were revealed by postoperative digital subtraction angiography. CONCLUSIONS: Endoscope-integrated ICG-VA seems to be an improvement that might increase the quality of aneurysm surgery by providing additional information. It offers higher illumination, magnification, and an extended viewing angle. Its main advantage is its ability to assess deep-seated aneurysms, especially through small craniotomies, but further studies are required.

[Principles of surgical treatment for patients with asymptomatic aneurysms and cerebral aneurysms in the cold period after spontaneous intracranial hemorrhages]

Surgical treatment of patients with cerebral aneurysms still remains one of the most important issues of cerebrovascular neurosurgery, which is associated with both complexity of treatment and risks posed by the disease. The purpose of this publication is to discuss the recommendations and algorithms adopted at the Neurosurgical Institute for choosing surgical treatment of patients with single and multiple intracranial aneurysms based on the clinical course of disease and anatomical morphological classifications of aneurysms. The study was based on a large clinical material: we analyzed treatment outcomes in 1,621 patients (2009-2017); of these, 966 (59.5%) patients were operated on using microsurgical techniques, and 655 (40.4%) patients underwent endovascular surgery. Surgical treatment of patients with cerebral aneurysms has been performed in close cooperation between two vascular (microsurgical and endovasal) departments, using the latest technical innovations.

[Surgical treatment of cerebral aneurysms in the Russian Federation]

OBJECTIVE

The objective of this study was to evaluate the results of surgical treatment of cerebral aneurysms in the Russian Federation.

MATERIAL AND METHODS

We analyzed performance indicators in neurosurgical departments of regional and federal health institutions of the Russian Federation for 2017. The results of surgical treatment of cerebral aneurysms (CAs) were analyzed in 19 regional vascular centers (RVCs) in several federal districts and in 3 federal centers (FCs) with the most dynamically developing vascular neurosurgery and smoothly running system of statistical data processing.

RESULTS

The study included 3160 patients hospitalized to 22 medical institutions in 2017. Of these, 1808 patients were treated in RVCs, and 1352 patients were treated in FCs. We analyzed factors affecting the treatment outcome in CA patients. We identified features of CA treatment in clinics with a different amount of surgical intervention.

CONCLUSION

An increase in the surgical activity in centers and simultaneous development of microsurgical and endovascular treatments for cerebral aneurysms reduce postoperative mortality. Due to the presence of a RVC network in the Russian Federation, many patients could receive necessary specialized treatment. The number of operations for cerebral aneurysms has increased 6-fold for the past 10 years.

The impact of temporary clipping during aneurysm surgery on the incidence of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

OBJECTIVE Clipping of a ruptured intracranial aneurysm requires some degree of vessel manipulation, which in turn is believed to contribute to vasoconstriction. One of the techniques used during surgery is temporary clipping of the parent vessel. Temporary clipping may either be mandatory in cases of premature rupture (rescue) or represent a precautionary or facilitating surgical step (elective). The aim of this study was to study the association between temporary clipping during aneurysm surgery and the incidence of vasospasm and delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage (aSAH) in a large clinical series. METHODS Seven hundred seventy-eight patients who underwent surgical aneurysm treatment after aSAH were retrospectively included in the study. In addition to surgical parameters, the authors recorded transcranial Doppler (TCD) sonography-documented vasospasm (TCD-vasospasm, blood flow acceleration > 120 cm/sec), delayed ischemic neurological deficits (DINDs), and delayed cerebral infarction (DCI). Multivariate binary logistic regression analysis was applied to assess the association between temporary clipping, vasospasm, DIND, and DCI. RESULTS Temporary clipping was performed in 338 (43.4%) of 778 patients during aneurysm surgery. TCD sonographic flow acceleration developed in 370 (47.6%), DINDs in 123 (15.8%), and DCI in 97 (12.5%). Patients with temporary clipping showed no significant increase in the incidence of TCD-vasospasm compared with patients without temporary clipping (49% vs 48%, respectively; p = 0.60). DINDs developed in 12% of patients with temporary clipping and 18% of those without temporary clipping (p = 0.01). DCI occurred in 9% of patients with temporary clipping and 15% of those without temporary clipping (p = 0.02). The need for rescue temporary clipping was a predictor for DCI; 19.5% of patients in the rescue temporary clipping group but only 11.3% in the elective temporary clipping group had infarcts (p = 0.02). Elective temporary clipping was not associated with TCD-vasospasm (p = 0.31), DIND (p = 0.18), or DCI (p = 0.06). CONCLUSIONS Temporary clipping did not contribute to a higher rate of TCD-vasospasm, DIND, or DCI in comparison with rates in patients without temporary clipping. In contrast, there was an association between temporary clipping and a lower incidence of DINDs and DCI. There is no reason to be hesitant in using elective temporary clipping if deemed appropriate.

Ruptured carotid-ophthalmic aneurysm treatment: a non-inferiority meta-analysis comparing endovascular coiling and surgical clipping

INTRODUCTION

Aneurysms of the carotid-ophthalmic segment are relatively rare, comprising only five percent of all intracranial aneurysms. There is no consensus regarding the optimal management for ruptured carotid-ophthalmic aneurysms, whether endovascular coiling or surgical clipping provide the most favourable patient outcome. The aim of this meta-analysis is to analyse these two treatment modalities for ruptured carotid-ophthalmic aneurysms with respect to independent clinical outcome.

METHODS

We performed a systematic literature search in PubMed, Cochrane Central Registry of Controlled Trials and Clinicaltrials.gov for treatment of ruptured carotid-ophthalmic aneurysms, comparing endovascular coiling and surgical clipping. Primary outcome in the study was independent clinical patient outcome at follow up (defined as Glasgow Outcome Scale four-five). Secondary outcomes were poor clinical patient outcome, mortality and total angiographic occlusion. The meta-analysis was performed using the Mantel-Haenszel method for dichotomous outcome.

RESULTS

Four studies met the inclusion criteria and were included in the meta-analysis. In total, 152 patients were included. Sixty-seven of these patients were treated with endovascular coiling and 85 patients were treated with microsurgical clipping. The proportion of patients with an independent clinical outcome after coiling and clipping was comparable, OR 1.04 (95% CI: 0.40, 2.71). The proportion of patients with an independent outcome in the endovascular group was 76% and in the surgical group 71%. Mortality between the two treatment arms was equal.

CONCLUSION

Clinical outcome after endovascular coiling and surgical clipping for ruptured carotid-ophthalmic aneurysms was comparable between surgical clipping and endovascular coiling. There was no proven difference in clinical outcome after endovascular coiling and surgical clipping for ruptured carotid-ophthalmic aneurysms but the evidence was based on few studies of moderate to low quality and we cannot rule out the possibility of a difference in clinical outcome between the two treatment modalities.

Intracranial aneurysm in a patient with glucocorticoid-remediable aldosteronism

Glucocorticoid-remediable aldosteronism (GRA) is an autosomal dominant disorder in which the increase in aldosterone secretion produced by Adrenocorticotropic hormone (ACTH) is no longer transient. Here we present a case of a 32-year-old man with GRA who was found to have an intracranial aneurysm following screening. His blood pressure had been well controlled and closely monitored since diagnosis and the institution of treatment at age 13 years. This is a rarely reported example of this manifestation in GRA, and both the treatment and rationale for therapy are discussed below.