Taming the exoscope: a one-year prospective laboratory training study.

PURPOSE: Digital 3D exoscopes have been recently introduced as an alternative to a surgical microscope in microneurosurgery. We designed a laboratory training program to facilitate and measure the transition from microscope to exoscope. Our aim was to observe the effect of a one-year active training on microsurgical skills with the exoscope by repeating a standardized test task at several time points during the training program. METHODS: Two board-certified neurosurgeons with no previous exoscope experience performed the same test tasks in February, July, and November during a 12-month period. In between the test tasks, both participants worked with the exoscope in the laboratory and assisted during clinical surgeries on daily basis. Each of the test segments consisted of repeating the same task 10 times during one week. Altogether, 60 test tasks were performed, 30 each. The test task consisted of dissecting and harvesting the ulnar and radial arteries of the second segment of a chicken wing using an exoscope (Aesculap AEOS). Each dissection was recorded on video and analyzed by two independent evaluators. We measured the time required to complete the task as well as several metrics for evaluating the manual skills of the dissection and handling of the exoscope system. RESULT: There was a clear reduction in dissection time between the first and the last session, mean 34 min (SD 5.96) vs. 26 min (SD 8.69), respectively. At the end of the training, both neurosurgeons used the exoscope more efficiently utilizing more available options of the device. There was correlation between the dissection time and several of the factors we used for evaluating the work flow: staying in focus, zoom control, reduction of unnecessary movements or repetitive manual motions, manipulation technique of the vessel under dissection, handling of the instruments, and using them for multiple dissection purposes (stretching, cutting, and splitting). CONCLUSION: Continuous, dedicated long-term training program is effective for microsurgical skill development when switching from a microscope to an exoscope. With practice, the micromotor movements become more efficient and the use of microinstruments more versatile.

Imaging features and ultraearly hematoma growth in intracerebral hemorrhage associated with COVID-19.

PURPOSE: Intracerebral hemorrhage (ICH) is an uncommon but deadly event in patients with COVID-19 and its imaging features remain poorly characterized. We aimed to describe the clinical and imaging features of COVID-19-associated ICH. METHODS: Multicenter, retrospective, case-control analysis comparing ICH in COVID-19 patients (COV19 +) versus controls without COVID-19 (COV19 -). Clinical presentation, laboratory markers, and severity of COVID-19 disease were recorded. Non-contrast computed tomography (NCCT) markers (intrahematoma hypodensity, heterogeneous density, blend sign, irregular shape fluid level), ICH location, and hematoma volume (ABC/2 method) were analyzed. The outcome of interest was ultraearly hematoma growth (uHG) (defined as NCCT baseline ICH volume/onset-to-imaging time), whose predictors were explored with multivariable linear regression. RESULTS: A total of 33 COV19 + patients and 321 COV19 - controls with ICH were included. Demographic characteristics and vascular risk factors were similar in the two groups. Multifocal ICH and NCCT markers were significantly more common in the COV19 + population. uHG was significantly higher among COV19 + patients (median 6.2 mL/h vs 3.1 mL/h, p = 0.027), and this finding remained significant after adjustment for confounding factors (systolic blood pressure, antiplatelet and anticoagulant therapy), in linear regression (B(SE) = 0.31 (0.11), p = 0.005). This association remained consistent also after the exclusion of patients under anticoagulant treatment (B(SE) = 0.29 (0.13), p = 0.026). CONCLUSIONS: ICH in COV19 + patients has distinct NCCT imaging features and a higher speed of bleeding. This association is not mediated by antithrombotic therapy and deserves further research to characterize the underlying biological mechanisms.

Clipping versus coiling for treatment of middle cerebral artery aneurysms: a retrospective Italian multicenter experience.

Endovascular treatment has emerged as the predominant approach in intracranial aneurysms. However, surgical clipping is still considered the best treatment for middle cerebral artery (MCA) aneurysms in referral centers. Here we compared short- and long-term clinical and neuroradiological outcomes in patients with MCA aneurysms undergoing clipping or coiling in 5 Italian referral centers for cerebrovascular surgery. We retrospectively reviewed 411 consecutive patients admitted between 2015 and 2019 for ruptured and unruptured MCA aneurysm. Univariate and multivariate analyses of the association between demographic, clinical, and radiological parameters and ruptured status, type of surgical treatment, and clinical outcome at discharge and follow-up were performed. Clipping was performed in 340 (83%) cases, coiling in 71 (17%). Clipping was preferred in unruptured aneurysms and in those showing collateral branches originating from neck/dome. Surgery achieved a higher rate of complete occlusion at discharge and follow-up. Clipping and coiling showed no difference in clinical outcome in both ruptured and unruptured cases. In ruptured aneurysms age, presenting clinical status, intracerebral hematoma at onset, and treatment-related complications were significantly associated with outcome at both short- and long-term follow-up. The presence of collaterals/perforators originating from dome/neck of the aneurysms also worsened the short-term clinical outcome. In unruptured cases, only treatment-related complications such as ischemia and hydrocephalus were associated with poor outcome. Clipping still seems superior to coiling in providing better short- and long-term occlusion rates in MCA aneurysms, and at the same time, it appears as safe as coiling in terms of clinical outcome.

Transethmoidal encephalocele endoscopically treated in a newborn: a case report.

Congenital encephalocele is a very rare entity, with herniation of normal brain or gliotic tissue through a defect in the skull. The objective is to present a newborn child diagnosed with transethmoidal encephaloceles at birth. She developed respiratory problems, feeding difficulties, and failure to thrive since the first days of life and so required early surgery at her 33th day of life, through an endoscopic nasal approach. Technical difficulties encountered, complications, and management are discussed. To the best of our knowledge, this is the first report of endoscopic treatment of transethmoidal encephalocele in a newborn. Further studies are needed to understand the best way to repair the dural defect in this rare condition.

Pneumocephalus in subthalamic deep brain stimulation for Parkinson's disease: a comparison of two different surgical techniques considering factors conditioning brain shift and target precision.

BACKGROUND: Precise placement of electrodes in deep brain stimulation (DBS) may be influenced by brain shift caused by cerebrospinal fluid leaking or air inflow. We compared accuracy and treatment outcomes between a standard technique and one aiming at reducing brain shift. METHODS: We retrospectively reviewed 46 patients (92 targets) treated with bilateral subthalamic-DBS for Parkinson's disease. The patients were divided into two groups: group A surgery was performed in supine position with standard burr hole, dural opening, fibrin glue and gelfoam plugging. Group B patients were operated in a semi-sitting position with direct dural puncture to reduce CSF loss. We analysed target deviation on head CT performed immediately after surgery and at 1 month merged with preoperative MRI planning. We recorded pneumocephalus volume, brain atrophy and target correction by intraoperative neurophysiology (ION). RESULTS: In group A, the mean pneumocephalus volume was 10.55 cm3, mean brain volume 1116 cm3, mean target deviation 1.09 mm and ION corrected 70% of targets. In group B, mean pneumocephalus was 7.60 cm3 (p = 0.3048), mean brain volume 1132 cm3 (p = 0.6526), mean target deviation 0.64 mm (p = 0.0074) and ION corrected 50% of targets (p = 0.4886). Most leads' deviations realigned to the planned target after pneumocephalus reabsorbtion suggesting a deviation caused by displacement of anatomical structures due to brain shift. Definitive lead position was always decided with ION. CONCLUSIONS: The modified DBS technique significantly reduced errors of electrode placement, though such difference was clinically irrelevant. ION corrected a high amount of trajectories in both groups (70% vs 50%). The choice of either strategy is acceptable.

Radiological outcomes for endovascular treatment of posterior communicating artery aneurysms: a retrospective multicenter study of the occlusion rate.

Although several innovations in techniques and implantable devices were reported over the last decades, a consensus on the best endovascular treatment for intracranial aneurysms originating from the posterior communicating artery is still missing. This work investigates radiological outcomes of different endovascular techniques for posterior communicating artery aneurysms treatment in a retrospective multi-centric cohort. We included patients endovascularly treated for posterior communicating artery aneurysms from 2015 through 2020 in six tertiary referral hospitals. We evaluated the relationship between patients and aneurysms characteristics, baseline neurological status, radiological outcomes, and the different endovascular techniques. Overall, 250 patients were included in this study. Simple coiling was the most frequent treatment in 171 patients (68%), followed by flow-diverter stenting in 32 cases (13%). Complete occlusion was reported in 163 patients (65%), near-complete occlusion in 43 (17%), and incomplete occlusion in 44 (18%). Radiological follow-up was available for 247 (98%) patients. The occlusion rate was stable in 149 (60%), improved in 49 (19%), and worsened in 51 (21%). No significant difference in exclusion rate was seen between ruptured and unruptured aneurysms at the last follow-up (p = 0.4). Posterior communicating artery thrombosis was reported in 25 patients (9%), transient ischemic attack in 6 (2%), and in 38 patients (15%), subsequent procedures were needed due to incomplete occlusion or reperfusion. Endovascular strategies for posterior communicating artery aneurysms represent effective and relatively safe treatments. Simple coiling provides a higher immediate occlusion rate, although recanalization has been frequently reported, conversely, flow-diversion devices provide good long-term radiological outcomes.

Techniques for pneumocephalus and brain shift reduction in DBS surgery: a review of the literature.

Deep brain stimulation has become an established therapeutic choice to manage the symptoms of medically refractory Parkinson's disease. Its efficacy is highly dependent on the accuracy of electrodes' positioning in the correct anatomical target. During DBS procedure, the opening of the dura mater induces the displacement of neural structures. This effect mainly depends on the loss of the physiological negative intracranial pressure, air inflow, and loss of cerebrospinal fluid. Several studies concentrated on correcting surgical techniques for DBS electrodes' positioning in order to reduce pneumocephalus which may result in therapeutic failure. The authors focused in particular on reducing the brain air window and maintaining the pressure gradient between intra- and extracranial compartments. A significant reduction of pneumocephalus and brain shift was obtained by excluding the opening of the subarachnoid space, by covering the dura mater opening with tissue sealant and by reducing the intracranial pressure in general anesthesia. Smaller burr hole diameters were not statistically relevant for reducing air inflow and displacement of anatomical targets. The review of the literature showed that conserving a physiological intra-extracranial pressure gradient plays a fundamental role in avoiding pneumocephalus and consequent displacement of brain structures, which improves surgical accuracy and DBS long-term results.

To drill or not to drill, that is the question: nonsurgical treatment of chronic subdural hematoma in the elderly. A systematic review.

OBJECTIVE: Chronic subdural hematoma (CSDH) is one of the most common neurosurgical pathologies, typically affecting the elderly. Its incidence is expected to grow along with the aging population. Surgical drainage represents the treatment of choice; however, postoperative complications and the rate of recurrence are not negligible. For this reason, nonsurgical alternatives (such as middle meningeal artery embolization, steroids, or tranexamic acid administration) are gaining popularity worldwide and need to be carefully evaluated, especially in the elderly population. METHODS: The authors performed a systematic review according to PRISMA criteria of the studies analyzing the nonsurgical strategies for CSDHs. They collected all papers in the English language published between 1990 and 2019 by searching different medical databases. The chosen keywords were "chronic subdural hematoma," "conservative treatment/management," "pharmacological treatment," "non-surgical," "tranexamic acid," "dexamethasone," "corticosteroid," "glucocorticoid," "middle meningeal artery," "endovascular treatment," and "embolization." RESULTS: The authors ultimately collected 15 articles regarding the pharmacological management of CSDHs matching the criteria, and 14 papers included the endovascular treatment. CONCLUSIONS: The results showed that surgery still represents the mainstay in cases of symptomatic patients with large CSDHs; however, adjuvant and alternative therapies can be effective and safe in a carefully selected population. Their inclusion in new guidelines is advisable.

Acute subdural hematoma in the elderly: outcome analysis in a retrospective multicentric series of 213 patients.

OBJECTIVE: The objective of this study was to analyze the risk factors associated with the outcome of acute subdural hematoma (ASDH) in elderly patients treated either surgically or nonsurgically. METHODS: The authors performed a retrospective multicentric analysis of clinical and radiological data on patients aged ≥ 70 years who had been consecutively admitted to the neurosurgical department of 5 Italian hospitals for the management of posttraumatic ASDH in a 3-year period. Outcome was measured according to the Glasgow Outcome Scale (GOS) at discharge and at 6 months' follow-up. A GOS score of 1-3 was defined as a poor outcome and a GOS score of 4-5 as a good outcome. Univariate and multivariate statistics were used to determine outcome predictors in the entire study population and in the surgical group. RESULTS: Overall, 213 patients were admitted during the 3-year study period. Outcome was poor in 135 (63%) patients, as 65 (31%) died during their admission, 33 (15%) were in a vegetative state, and 37 (17%) had severe disability at discharge. Surgical patients had worse clinical and radiological findings on arrival or during their admission than the patients undergoing conservative treatment. Surgery was performed in 147 (69%) patients, and 114 (78%) of them had a poor outcome. In stratifying patients by their Glasgow Coma Scale (GCS) score, the authors found that surgery reduced mortality but not the frequency of a poor outcome in the patients with a moderate to severe GCS score. The GCS score and midline shift were the most significant predictors of outcome. Antiplatelet drugs were associated with better outcomes; however, patients taking such medications had a better GCS score and better radiological findings, which could have influenced the former finding. Patients with fixed pupils never had a good outcome. Age and Charlson Comorbidity Index were not associated with outcome. CONCLUSIONS: Traumatic ASDH in the elderly is a severe condition, with the GCS score and midline shift the stronger outcome predictors, while age per se and comorbidities were not associated with outcome. Antithrombotic drugs do not seem to negatively influence pretreatment status or posttreatment outcome. Surgery was performed in patients with a worse clinical and radiological status, reducing the rate of death but not the frequency of a poor outcome.

Neurosurgery in times of a pandemic: a survey of neurosurgical services during the COVID-19 outbreak in the Veneto region in Italy.

OBJECTIVE: The purpose of this study was to analyze the effect of the coronavirus disease 2019 (COVID-19) outbreak and of the subsequent lockdown on the neurosurgical services of the Veneto region in Italy compared to the previous 4 years. METHODS: A survey was conducted in all 6 neurosurgical departments in the Veneto region to collect data about surgical, inpatient care and endovascular procedures during the month of March for each year from 2016 to 2020. Safety measures to avoid infection from SARS-CoV-2 and any COVID-19 cases reported among neurosurgical patients or staff members were considered. RESULTS: The mean number of neurosurgical admissions for the month of March over the 2016-2019 period was 663, whereas in March 2020 admissions decreased by 42%. Emergency admissions decreased by 23%. The average number of neurosurgical procedures was 697, and declined by 30% (range -10% to -51% in individual centers). Emergency procedures decreased in the same period by 23%. Subarachnoid hemorrhage and spontaneous intracerebral hemorrhage both decreased in Veneto-by 25% and 22%, respectively. Coiling for unruptured aneurysm, coiling for ruptured aneurysm, and surgery for ruptured aneurysm or arteriovenous malformation diminished by 49%, 27%, and 78%, respectively. Endovascular procedures for acute ischemic stroke (AIS) increased by 33% in 2020 (28 procedures in total). There was a slight decrease (8%) in brain tumor surgeries. Neurosurgical admissions decreased by 25% and 35% for head trauma and spinal trauma, respectively, while surgical procedures for head trauma diminished by 19% and procedures for spinal trauma declined by 26%. Admissions and surgical treatments for degenerative spine were halved. Eleven healthcare workers and 8 patients were infected in the acute phase of the pandemic. CONCLUSIONS: This multicenter study describes the effects of a COVID-19 outbreak on neurosurgical activities in a vast region in Italy. Remodulation of neurosurgical activities has resulted in a significant reduction of elective and emergency surgeries compared to previous years. Most likely this is a combined result of cancellation of elective and postponable surgeries, increase of conservative management, increase in social restrictions, and in patients' fear of accessing hospitals. Curiously, only endovascular procedures for AIS have increased, possibly due to reduced physical activity or increased thrombosis in SARS-CoV-2. The confounding effect of thrombectomy increase over time cannot be excluded. No conclusion can be drawn on AIS incidence. Active monitoring with nasopharyngeal swabs, wearing face masks, and using separate pathways for infected patients reduce the risk of infection.

Utility of 3D rotational angiography road map in flow diverter deployment in a distal dissecting MCA aneurysm.

Distal, dissecting, middle cerebral artery (MCA) aneurysms are changing surgically and endovascularly. Endovascular treatment requires flow diverter stenting. A good vessel visualization is crucial for safe navigation. Three-dimensional rotational digital subtraction angiography (3D-DSA) is used routinely in diagnostic imaging. The utilization of the 3D-DSA road map in vessel navigation and stent deployment is novel. An illustrative video of a distal, dissecting left MCA aneurysm treated with flow diverter stenting is presented. The technical issues were distal location, dissecting nature with double lumen, proximal stenosis, and vessel curves. The 3D-DSA road map helped to enhance visualization with a safer procedure.The video can be found here: https://youtu.be/sS3o1Z0P8WE.

Single-approach vertebral osteosynthesis in the treatment of spinal osteolysis by spondylodiscitis.

OBJECTIVEBoth spontaneous and iatrogenic spondylodiscitis are becoming ever more frequent, yet there are no definite treatment guidelines. For many years the treatment protocol was conservative medical management or surgical debridement with patients immobilized or bedridden for weeks and often resulting in spinal deformity. The eventual development of spinal deformity can be difficult to treat. Over the last few years, the authors have preferred a single-approach instrumented arthrodesis when spondylolysis that evolves in deformity from somatic wedging occurs.METHODSThe authors retrospectively reviewed the clinical, radiological, and surgical records of 11 patients treated over the past 3 years for spondylodiscitis with osteosynthesis.RESULTSOverall, the authors treated 11 patients: 3 cases with tuberculous spondylodiscitis (1 dorsal, 2 lumbar); 6 cases with Staphylococcus aureus spondylodiscitis (1 cervical, 2 dorsal, 2 lumbar, 1 dorsolumbar); 1 spondylodiscitis with postsurgical lumbar deformity; and in 1 dorsolumbar case the germ was not identified. Surgical approaches were chosen according to spinal level: In 8 dorsolumbar cases a posterior osteosynthesis was achieved. In 1 cervical case an anterior approach was performed with autologous bone graft from iliac crest. In 2 thoracolumbar cases a posterolateral costotransversectomy was needed. In 1 lumbosacral case iliac somatic grafting was used. Ten patients received adequate antibiotic treatment with clinical remission, and 1 case is in initial follow-up. No complications due to instrumentation were recorded. Spinal deformity was prevented in 10 cases, whereas preexisting spinal deformity was partially corrected in 1 case. In all cases, arthrodesis achieved vertebral stability.CONCLUSIONSThis study has the limitations of a retrospective review with a limited number of patients. Instrumentation does not appear to hamper healing from infection. Moreover, spinal stabilization, which is assisted by the infectious process even in the absence of bone graft, allows early mobilization. Instrumented osteosynthesis should be preferred for spondylodiscitis with osteolysis and spinal instability because it allows early mobilization and rehabilitation whenever necessary. It prevents spinal deformity and does not hamper healing of infections.

Complete embolization of jugular paragangliomas by direct puncture. Technical note.

Objective: Intra-arterial embolization of jugular paragangliomas is an established endovascular technique. Intratumoral embolization by direct puncture has been proposed, prior to surgical treatment or radiosurgery to reduce the risk of cranial nerve deficits. Methods: We examined the technical aspects of two patients with jugular paragangliomas embolized with liquid embolic agent by direct puncture of the lesion, as sole treatment. Results: Two patients with jugular paragangliomas presented with lower cranial nerve deficits. The first patient showed an extended lesion (55-mm) and was treated with partial intra-arterial embolization plus direct puncture and injection of Squid 18 and a second staged embolization by direct puncture and filling of the remainder of the lesion. The second patient with a smaller jugular paraganglioma (33-mm) was treated by single embolization by direct puncture of the tumor and injection of Squid 12 and Squid 18 obtaining complete filling of the lesion. No procedural complications were observed. Both patients showed no residual and initial improvement of the neurological deficits. Conclusion: The intratumoral embolization by direct puncture of jugular paragangliomas, under accurate radiological control is a safe procedure, and complete exclusion of the lesion can be obtained in selected cases. A staged particle embolization of the lesion by direct puncture can be proposed for large lesions. Only further studies with larger series and long-term follow-up will be able to define, if this strategy can be curative avoiding additional surgical or radio-surgical treatment.

Outcome of patients affected by newly diagnosed glioblastoma undergoing surgery assisted by 5-aminolevulinic acid guided resection followed by BCNU wafers implantation: a 3-year follow-up.

The purpose of the study was to evaluate the clinical outcome of the association of BCNU wafers implantation and 5-aminolevulinic acid (5-ALA) fluorescence in the treatment of patients with newly diagnosed glioblastoma (ndGBM). Clinical and surgical data from patients who underwent 5-ALA surgery followed by BCNU wafers implantation were retrospectively evaluated (20 patients, Group I) and compared with data of patients undergoing surgery with BCNU wafers alone (42 patients, Group II) and 5-ALA alone (59 patients, Group III). Patients undergoing 5-ALA assisted resection followed by BCNU wafers implantation (Group I) resulted long survivors (>3 years) in 15 % of cases and showed a median PFS and MS of 11 and 22 months, respectively. Patients treated with BCNU wafers presented a significantly higher survival when tumor was removed with the assistance of 5-ALA (22 months with vs 18 months without 5-ALA, p < 0.0001); these data could be partially explained by the significantly higher CRET achieved in patients operated with 5-ALA assistance (80 % with vs 47 %% without 5-ALA). Moreover, patients of Group I showed a significant increased survival compared with Group III (5-ALA without BCNU) (22 months with vs 21 months without BCNU wafers, p = 0.0025) even with a comparable CRET (80 % vs 76 %, respectively). The occurrence of adverse events related to wafers did not significantly increase with 5-ALA (20 % with and 19 % without 5-ALA) and did not impact in survival outcome. In conclusion, our experience shows that on selected ndGBM patients 5-ALA technology and BCNU wafers implantation show a synergic action on patients' outcome without increasing adverse events occurrence.

Utility of indocyanine green videoangiography in subcortical arteriovenous malformation resection.

Subcortical arteriovenous malformations (AVMs) are surgically challenging. Localization is crucial for eloquent areas, and complete resection evaluation is uncertain. Indocyanine green videoangiography (ICG-VA) can assist this surgery. An illustrative video of a subcortical frontoparietal bleeding AVM resection assisted by ICG-VA is presented. A bleeding arterial feeder aneurysm was embolized in the acute phase to protect against rebleeding. ICG-VA helped to detect the AVM's superficial arterialized draining vein, distinguishing it from normal cortical veins. This enabled a customized sulcus approach. ICG-VA showed normalized flow through the previously arterialized vein, confirming the AVM's complete resection. This applies when there is a single drainage remaining. The video can be found here: https://youtu.be/L7yJEE66kV0 .

ICG-VA application in subtemporal transtentorial treatment of a Cognard V dural arteriovenous fistula.

Intracranial dural arteriovenous fistulas (dAVF) with cervical perimedullary drainage, Cognard V, are a surgically challenging rare entity. In this video we show the disconnection of a right tentorial Cognard V dAVF, done through a subtemporal transtentorial approach with the application of indocyanine green video angiography. A 47-year-old man presented with severe tetraparesis. Only partial embolization was possible. An osteoplastic frontotemporal craniotomy was performed to obtain a wide view along with CSF release to safely mobilize the temporal lobe. Neuronavigation was used to detect the fistula and indocyanine to detect the tentorial afferent arteries and to confirm final disconnection. The video can be found here: https://youtu.be/Yr8tAiiHNXU .

The suboccipital midline approach to foramen magnum meningiomas.

BACKGROUND: Anterior and anterolateral meningiomas of the foramen magnum (FM) can be resected either through extensive skull base approaches or through the classical suboccipital midline approach with limited bone removal. METHOD: This paper describes the suboccipital midline approach focusing on some peculiar technical features that serve to achieve the necessary space for safe resection of these challenging tumors. CONCLUSIONS: In our experience, by adopting appropriate strategies to gain space (some of them natural, others acquired) the suboccipital midline approach can achieve the safe resection of anterior and anterolateral FM meningiomas in the majority of cases.