Surgical outcomes in patients with acromegaly: Microscopic vs. endoscopic transsphenoidal surgery.

Transsphenoidal resection of growth hormone-secreting pituitary neuroendocrine tumors remains the first-line treatment for acromegaly. This can be performed through microsurgery or endoscopic surgery. For the past decades, endoscopic surgery has become the preferred technique in an increasing number of centers worldwide. However, whether it offers superior clinical outcomes has yet to be determined. In this paper, we performed a narrative review of the literature comparing both techniques in the treatment of acromegaly. We critically assessed available comparative studies from an objective perspective to determine their suitability for defining superiority of either technique. Available evidence displays substantial methodological variations and reports conflicting findings. Although endoscopic surgery provides a wider exposure and enhanced visibility of the surgical field, this does not consistently translate into better clinical outcomes, as most tumors are equally accessible through both techniques. Postoperative outcomes such as remission and complication rates are similar between both techniques. The management of acromegaly should be performed by experienced pituitary neurosurgeons, regardless of the approach. The involvement of a multidisciplinary team in a dedicated pituitary center is critical to ensure optimal outcomes.

Novel Hybrid Technique for Preservation of Frontal Branch of Facial Nerve: Subgaleal Preinterfascial Dissection.

OBJECTIVE: The pterional approach is the workhorse of skull-base neurosurgery, which allows virtual access to any intracranial lesion around the circle of Willis. Preserving the frontotemporal branch of the facial nerve and conserving the temporal muscle's symmetry are fundamental objectives besides the access that can be obtained through this versatile neurosurgical technique. This manuscript proposes a subgaleal preinterfascial dissection, a novel hybrid technique that provides advantages of previously described temporal muscle dissection techniques while preserving the integrity of facial nerve branches and the unobstructed broad pterional region. We describe the subgaleal preinterfascial dissection as a safe and simple to technique to achieve preservation of the facial nerve frontal branches during anterolateral approaches. METHODS: Two cadaveric heads were skillfully dissected and studied to perform a proper subgaleal preinterfascial dissection on both sides of each cadaver. Afterward, the same technique was employed in 108 patients during a pterional approach for different neurosurgical diseases, with a postoperative follow-up of 6 months. RESULTS: None of the 108 patients presented postoperative frontotemporal branch palsy during postoperative follow-up. Likewise, no complications related to the proposed technique were present. CONCLUSIONS: The subgaleal preinterfascial dissection is a reliable, safe technique that may be employed during a pterional approach with an unobstructed surgical view and excellent cosmetic and functional results, preserving the frontotemporal branch of the facial nerve.

Defining the limits of the anterior wall of the cavernous sinus through an endoscopic view: Cadaveric anatomical study.

Background: The anterior wall of the cavernous sinus (CS) represents an important landmark for endoscopic surgery that although mentioned before, no precise anatomical boundaries have been described. We describe the anatomical landmarks that delimit the anterior wall of the CS, emphasizing its importance as a reference for accessing the CS through endoscopic approaches. Methods: Six adult cadaveric heads fixed with formaldehyde and injected with colored silicone were studied. In all the heads, an endonasal endoscopic approach to the sellar and parasellar regions was performed and the anatomy of the anterior wall of the CS was studied. Results: Four consistent anatomical landmarks that mark the limits of the anterior wall of the CS were found in all the specimens: anterosuperiorly, the lateral opticocarotid recess; posterosuperiorly, the medial opticocarotid recess; anteroinferiorly, the inferior part of the maxillary strut; and posteroinferiorly, the superolateral angle of the clival recess. Conclusion: It is of paramount importance to recognize the anatomical landmarks that define the limits of the anterior wall of the CS to achieve a safe access to this so complex region.

Current and Future Perspectives of Microscopic and Endoscopic Transsphenoidal Surgery for Pituitary Adenomas: A Narrative Review.

Transsphenoidal resection remains the standard treatment for most pituitary adenomas. However, the ideal surgical approach to safely access these lesions, either microsurgical or endoscopic, continues to be debated. Since the introduction of endoscopic transsphenoidal surgery, centers around the world have increasingly adopted this technique, experiencing a shift away from the conventional microsurgical approach. Large series reporting the efficacy and safety of endoscopic surgery have fueled a growing interest in comparing clinical outcomes between both approaches. Still, proving superiority of either surgical approach remains an elusive task due to the inherent drawbacks of surgical observational studies, as we are still faced with a growing body of evidence reporting conflicting results. Thus, a comprehensive discussion regarding the reach and limitations of both techniques becomes necessary. In this narrative review, we perform a critical appraisal of the literature and provide an expert opinion on the state-of-the-art in transsphenoidal surgery for pituitary adenomas. The advantages and limitations of each approach are assessed and compared from a technical standpoint, and their reported outcomes evaluated in the framework of this transition phase. Available evidence should be interpreted in light of individual patient characteristics and within the context of each medical center, taking into consideration the known impact that surgical expertise and multidisciplinary management hold on clinical outcomes.

Prognostic Factors in the Surgery of Clinoidal Meningiomas.

INTRODUCTION: Clinoidal meningiomas are currently among the intracranial meningiomas with the greatest neurosurgical complexity, morbidity, and mortality associated with their resection. The worldwide literature has described tumor size (>4 cm3), patient age (>60 years), and invasion of the cavernous sinus as factors associated with a worse clinical outcome following surgery. METHODS: We describe the series of cases of patients with clinoidal meningiomas who underwent microsurgical resection at our institution between January 2014 and March 2019. The intention was to analyze the multiple preoperative variables, such as the patient's demographic, tumor, and surgical characteristics, such as the Al-Mefty Classification to find a relationship with the patient's clinical outcome during their postoperative follow-up.  Results: Death occurred in 4.8% of the cases. Postoperative morbidity was documented in 42.9%, the most frequent being ophthalmoparesis, followed by worsening of visual acuity, and new onset motor deficits. Radiological characteristics were assessed based on preoperative MRI. The maximum diameter, midline shift, invasion of the cavernous sinus, arterial encasement, and peritumoral edema were evaluated. Average intraoperative bleeding was 1.3 L. The most frequent histological grade was World Health Organization (WHO) grade 1 in 85.6% of the cases. Complete resection was obtained in 52.4% of the cases; 42.8% received fractionated stereotactic radiotherapy after surgery for disease control, and one received radiosurgery. Recurrence occurred in 33.3%. The average follow-up in months was 23.8.  Conclusions: Demographic factors and tumor characteristics in clinoidal meningioma surgery are related to the subtype of meningioma according to the Al-Mefty Classification and impact directly the degree of resection, progression of the disease, and degree of postoperative complications. To achieve maximal resection while minimizing morbidity and mortality, these factors must be considered to decide on an appropriate approach and specific plan for each case.

Photo-Stacking Technique for Neuroanatomical High-Definition Photography and 3-Dimensional Modeling.

BACKGROUND: Three-dimensional (3D) neuroanatomical knowledge is vital in neurosurgery. Technological advances improved 3D anatomical perception, but they are usually expensive and not widely available. The aim of the present study was to provide a detailed description of the photo-stacking technique for high-resolution neuroanatomical photography and 3D modeling. METHODS: The photo-stacking technique was described in a step-by-step approach. The time for image acquisition, file conversion, processing, and final production was measured using 2 processing methods. The total number and file size of images are presented. Measures of central tendency and dispersion report the measured values. RESULTS: Ten models were used in both methods achieving 20 models with high-definition images. The mean number of acquired images was 40.6 (14-67), image acquisition time 51.50 ± 18.8 s, file conversion time 250 ± 134.6 s, processing time 50.46 ± 21.46 s and 41.97 ± 20.84 s, and 3D reconstruction time was 4.29 ± 0.74 s and 3.89 ± 0.60 s for methods B and C, respectively. The mean file size of RAW files is 1010 ± 452 megabyte (MB) and 101.06 ± 38.09 MB for Joint Photographic Experts Group files after conversion. The mean size of the final image means size is 71.9 ± 0.126 MB, and the mean file size of the 3D model means is 37.4 ± 0.516 MB for both methods. The total equipment used was less expensive than other reported systems. CONCLUSIONS: The photo-stacking technique is a simple and inexpensive method to create 3D models and high-definition images that could prove valuable in neuroanatomy training.

Obstructive Hydrocephalus Due to Posterior Fossa Tumors in Adults: A Comparative Analysis of 3 Surgical Techniques.

BACKGROUND: The main treatments for hydrocephalus due to posterior fossa tumors are tumor resection with or without an external ventricular drain, ventriculoperitoneal shunt (VPS), and endoscopic third ventriculostomy. Although preoperative cerebrospinal fluid diversion by any of these techniques improves clinical outcomes, evidence comparing the efficacy of these techniques is scarce. Therefore, we aimed to retrospectively evaluate each treatment modality. METHODS: This single-center study analyzed 55 patients. Treatments were classified as successful (hydrocephalus resolution with a single surgical event) or failed and compared with a χ2 test. Kaplan-Meier curves and log-rank tests were employed. A Cox proportional hazard model was used to determine relevant covariates predicting outcomes. RESULTS: Mean patient age was 36.3 years, 43.4% of patients were men, and 50.9% of patients presented with uncompensated intracranial hypertension. Mean tumor volume was 33.4 cm3, and extent of resection was 90.85%. Tumor resection with or without an external ventricular drain was successful in 58.82% of cases, VPS was successful in 100%, and endoscopic third ventriculostomy was successful in 76.19% (P = 0.014). Mean follow-up time was 15.12 months. Log-rank test found statistically significant differences between survival curves of treatments (P = 0.016) favoring the VPS group. Postoperative surgical site hematoma was a significant covariate in the Cox model (hazard ratio = 17; 95% confidence ratio, 2.301-81.872; P = 0.004). CONCLUSIONS: This study favored VPS as the most reliable treatment of hydrocephalus due to posterior fossa tumors in adult patient; however, several factors influence clinical outcomes. We proposed an algorithm based on our findings and other authors' findings to facilitate the decision-making process.

Endoscopic endonasal clipping of a medial paraclinoid aneurysm with roadmapping assistance: Two-dimensional operative video.

Background: Advancements in endoscopic endonasal approaches (EEAs) allow the treatment of a wide variety of diseases including vascular pathology. Case Description: A 56-year-old woman presented with thunderclap headache due to two aneurysms: Communicating segment of left internal carotid artery (ICA) and medial paraclinoid (Baramii IIIB). The ICA aneurysm was clipped through a conventional transcranial approach; the paraclinoid aneurysm was successfully clipped using an EEA guided with roadmapping assistance. Conclusion: EEA is useful to treat aneurysms in selected cases and the use of adjuvant angiographical techniques such as roadmapping or proximal balloon control allow excellent control during the procedure.

Roadmapping technique in the hybrid operating room for the microsurgical treatment of complex intracranial aneurysms.

OBJECTIVE: To describe the roadmapping technique and our three-year experience in the management of intracranial aneurysms in the hybrid operating room. METHODS: We analyzed all patients who underwent surgical clipping for cerebral aneurysms with the roadmapping technique from January 2017 to September 2019. We report demographic, clinical, and morphological variables, as well as clinical and radiological outcomes. We further describe three illustrative cases of the technique. RESULTS: A total of 13 patients were included, 9 of which (69.2%) presented with subarachnoid hemorrhage, with a total of 23 treated aneurysms. All patients were female, with a mean age of 47.7 years (range 31-63). All cases were anterior circulation aneurysms, the most frequent location being the ophthalmic segment of the internal carotid artery (ICA) in 11 cases (48%), followed by posterior communicating in 8 (36%), and ICA bifurcation in 2 (8%). Intraoperative clip repositioning was required in 9 aneurysms (36%) as a result of the roadmapping technique in the hybrid operating room. There were no residual aneurysms in our series, nor reported mortality. CONCLUSIONS: The roadmapping technique in the hybrid operating room offers a complementary tool for the adequate occlusion of complex intracranial aneurysms, as it provides a real time fluoroscopic-guided clipping technique, and clip repositioning is possible in a single surgical stage, whenever a residual portion of the aneurysm is identified. This technique also provides some advantages, such as immediate vasospasm identification and treatment with intra-arterial vasodilators, balloon proximal control for certain paraclinoid aneurysms, and simultaneous endovascular treatment in selected cases during a single stage.

Treatment of middle cerebral artery aneurysms: A comparative study and proposed treatment algorithm.

OBJECTIVES: We aimed to compare outcomes of patients with middle cerebral artery (MCA) aneurysms treated by either microsurgical clipping or endovascular therapy and provide a treatment algorithm based on available evidence. MATERIALS AND METHODS: We performed a retrospective analysis of 77 patients with 95 MCA aneurysms. Demographic, clinical, and aneurysm morphological variables were collected. Patients were divided into two groups depending on the received treatment. Clinical and radiological outcomes were collected at the end of a 1-year follow-up period and compared between both treatment groups. RESULTS: Mean age was 51.4 years. Fifty patients (65%) underwent microsurgical clipping and 27 (35%) were treated by endovascular therapy. Fifty-four patients (70%) presented with subarachnoid hemorrhage, while 23 (30%) were treated for unruptured aneurysms. Patients with subarachnoid hemorrhage were more frequently treated by microsurgical clipping than patients with unruptured aneurysms. Clinical outcomes, including functional status, were similar between treatment groups after 1-year follow-up even when adjusting for clinical presentation. Residual aneurysms were found less frequently in the microsurgical group (OR = 0.09; p < 0.001). CONCLUSIONS: In patients with MCA aneurysms, clinical outcomes at 1 year are similar between microsurgical clipping and endovascular therapy. However, microsurgery is associated with a lower risk of residual aneurysms.

OBJETIVO: Evaluar y comparar desenlaces de pacientes con aneurismas de arteria cerebral media (ACM) tratados mediante clipaje microquirúrgico o terapia endovascular, y proponer un algoritmo de tratamiento basado en evidencia. MATERIAL Y MÉTODOS: Estudio retrospectivo de 77 pacientes con 95 aneurismas de ACM. Se recabaron variables demográficas, clínicas y morfológicas de los aneurismas tratados. Se dividieron a los pacientes en dos grupos dependiendo del tratamiento recibido y se compararon los desenlaces clínicos y radiológicos al final del seguimiento a un año entre ambos grupos. RESULTADOS: La edad promedio fue 51.4 años. 50 pacientes (65%) fueron sometidos a clipaje microquirúrgico y 27 (35%) a terapia endovascular. 54 pacientes (70%) presentaron hemorragia subaracnoidea, quienes fueron tratados mediante microcirugía en mayor proporción que aquellos con aneurismas no rotos. Los desenlaces clínicos, incluyendo el estado funcional, fueron similares entre ambos grupos al año de seguimiento, aún tras ajustar el análisis por presentación clínica. El grupo de microcirugía presentó una menor proporción de aneurismas residuales (OR = 0.09; p < 0.001). CONCLUSIONES: En pacientes con aneurismas de ACM, los desenlaces clínicos a un año son similares entre clipaje microquirúrgico y terapia endovascular. Sin embargo, la microcirugía se asocia a un menor riesgo de aneurismas residuales.

Carboplatin Plus Vincristine as an Alternative Chemotherapeutic Scheme in Patients With Glioblastoma.

Background and objective Alternative chemotherapy regimens, including cisplatin, carmustine, or other agents, have been shown to be effective; however, the use of carboplatin plus vincristine (C/V) has not been studied before. In this study, we aimed to determine the survival rates in patients treated with C/V, by comparing our findings with treatments based on temozolomide (TMZ), and to explore a possible relationship with the methylation status of the methylguanine methyltransferase (MGMT) promoter in patients with glioblastoma (GB). Methods A retrospective cohort study was conducted involving 45 surgically treated patients diagnosed with GB. Fresh tissue samples were examined by the DNA bisulfite conversion method to determine methylation status. After surgery, different chemotherapy regimens were employed as adjuvants. Follow-up of participants was performed as outpatients at three-month intervals to determine overall survival (OS), by comparing the use of TMZ versus C/V. Results MGMT promoter methylation status could only be determined in 35 samples; 20 patients received adjuvant chemotherapy, of which 14 were treated with C/V and six with TMZ-based schemes. The median OS (mOS) was eight months (range: 1-24 months). OS was 57.25% at six months, 48.7% at 12 months, and 28.5% at 24 months. In the TMZ group, an OS of 83% was observed at 24 months. In the C/V group, OS was 71.4% at six months, 57.1% at 12 months, and 35.7% at 24 months. Patients who did not receive adjuvant chemotherapy treatment had the lowest survival rates with an OS of 39.9% at six months, 26.6% at 12 months, and 19.9% ​​at 24 months. Conclusions Based on our findings, C/V offers an accessible and effective alternative treatment when the TMZ-based scheme is not accessible, providing higher rates of OS compared to patients without chemotherapy management. The methylation status of the MGMT promoter is a significant prognostic factor, resulting in higher survival rates among patients when it is methylated.

Middle Transclival Endoscopic Endonasal Resection of a Ventral Pontine Cavernous Malformation.

The surgical management of lesions within or around the brainstem is usually associated with significant morbidity. Even though several safe entry zones have been described for brainstem lesions, especially cavernous malformations (CMs), their resection remains a challenge due to the convergence of highly functional nerve tracts and nuclei in this rather small structure. Moreover, the ventral location of some of these lesions usually calls for complex surgical approaches involving extensive bone drilling and significant manipulation of neurovascular structures. The expanded endoscopic endonasal approach has been subject to considerable advancements, widening the range of lesions accessible through this route. In this operative video, we describe the surgical nuances of an endoscopic endonasal transclival resection of a ventral pontine CM (Figures 1 and 2). A pedicled nasoseptal flap was harvested for reconstruction, gaining access to the sphenoid rostrum, which was resected. The sellar floor was removed to expose the middle third of the clivus, which was drilled out until posterior fossa dura mater was identified. A centered dural incision was performed to expose the ventral pons and basilar artery. Using image guidance, a limited pial incision over the most superficial aspect of the lesion allowed a prompt drainage of the hematoma and resection of the CM. The surgical cavity was directly inspected through the endoscope, confirming a complete resection. Reconstruction was carried out in a multilayered fashion. The patient presented a postoperative cerebrospinal fluid leak, which resolved with a lumbar drain. Neurologic status remained unchanged after surgery, with the patient displaying a favorable clinical outcome (Video 1).

Burnout, Discrimination, Abuse, and Mistreatment in Latin America Neurosurgical Training During the Coronavirus Disease 2019 Pandemic.

BACKGROUND: Discrimination, abuse, and mistreatment are prevailing problems reported in neurosurgical training programs globally. Moreover, the current coronavirus disease 2019 (COVID-19) pandemic may also show a negative impact on burnout levels in neurosurgery residents. This study aims to evaluate burnout, discrimination, and mistreatment in neurosurgical residents training in Latin America during the severe acute respiratory syndrome coronavirus 2 era. METHODS: A 33-item electronic survey was sent to neurosurgery residents from Latin America from May 10 to 25, 2021. Statistical analysis was performed using SPSS version 25. RESULTS: A total of 111 neurosurgery residents responded to the survey. Mean age was 29.39 ± 2.37 years; 22.5% were female and 36% were training in Mexico. Residents who reported experiencing discrimination for testing positive to COVID-19 had the highest levels of depersonalization (66.7%; P = 0.043) and emotional exhaustion (75%; P = 0.023). Female respondents reported higher rates of gender discrimination (80% vs. 1.2%; P = 0.001), abuse (84% vs. 58.1%; P < 0.005), and sexual harassment (24% vs. 0%; P < 0.001) than did male respondents. Residents training in Mexico reported lower rates of emotional or verbal abuse (59.2% vs. 32.5%; P = 0.007) and bullying (P < 0.005) than did those in other countries in Latin America. Older age was a protective factor for high depersonalization scores (odds ratio [OR], 0.133; 95% confidence interval [CI], 0.035-0.500). Experiencing discrimination represented a risk factor for presenting high emotional exhaustion scores (OR, 3.019; 95% CI, 1.057-8.629). High levels of depersonalization were associated with a 7-fold increased risk of suicidal ideation (OR, 7.869; 95% CI, 1.266-48.88). CONCLUSIONS: The COVID-19 pandemic has been a significant burden on several aspects of health care workers' lives. Our results provide a broad overview of its impact on burnout, discrimination, and mistreatment as experienced by neurosurgery residents training in Latin America, laying the groundwork for future studies and potential interventions.

Combined Endoscopic Transsphenoidal and Tubular Retractor-Assisted Transventricular Approach for Giant Pituitary Adenomas.

BACKGROUND: Surgical resection remains the standard treatment for most giant pituitary adenomas (GPAs). The selected surgical approach for these complex lesions depends mainly on their extension. Single approaches may be limited in some cases presenting with invasion into multiple compartments, thereby limiting extent of resection. METHODS: We report a series of patients with GPA operated on through a combined approach involving an endoscopic endonasal transsphenoidal approach and a tubular retractor-assisted transventricular approach, describing the technique, its indications, limitations, and outcomes. Baseline and postoperative clinical, functional, and morphologic variables were documented up until each patient's last follow-up visit. RESULTS: Five patients harboring tumors extending into the third and lateral ventricles were included. Mean extent of resection was 94.6%. Mean follow-up was 39.4 months. One patient presented with a growth hormone-secreting GPA, who achieved remission after repeat resection during follow-up. There were no intraoperative complications, and 1 patient required reoperation for cerebrospinal fluid leak repair. One patient received adjuvant radiotherapy, and 3 patients remained stable requiring no additional treatment. All patients maintained an adequate postoperative functional status. CONCLUSIONS: The combined approach herein described may be a safe and effective option for some patients with GPAs extending into the third and lateral ventricles. An adequate patient selection is mandatory to exploit the benefits of each individual approach.

Petroclival Meningiomas: A Simple System That Could Help in Selecting the Approach.

BACKGROUND: Petroclival meningiomas (PCM) represent a neurosurgical challenge due to their strategic location close to the brainstem. OBJECTIVE: To assess the applicability of a retrosigmoid approach (RSA) by analyzing the degree of displacement of the middle cerebellar peduncle (MCP) elicited by PCM. METHODS: Patients with PCM were prospectively included and divided into those whose imaging studies showed that the posterior end of the MCP was displaced by the tumor and were eligible for and underwent RSA (group A) and those who were not eligible for RSA and who underwent surgery via a posterior transpetrosal approach (group B). We compared tumor behavior, clinical characteristic of patients and surgical results. RESULTS: Twenty patients with PCM were enrolled and allocated to group A (n = 15) or group B (n = 5). The clinical manifestations were more severe in group B; tumors in this group were larger and gross total removal was achieved in only 1 patient (20%). In comparison, in 12 cases on group A, tumors could be totally removed (80%) and all of these patients could recover their quality of life after surgery. CONCLUSION: To our knowledge, this study is the first to consider displacement of the MCP when establishing a suitable surgical approach for PCM. Our results suggest that the RSA becomes increasingly suitable when peduncle displacement is greater. By using this method, it was also possible to identify two types of tumors: petroclivals (group A) and clivopetrosals (group B), that show some specific clinical and surgical differences.

68Ga-DOTATOC-PET/CT-guided resection of a primary intraosseous meningioma: technical note.

Primary intraosseous meningiomas (PIMs) are rare tumors that present with a variable radiological appearance and a clinical behavior that is considerably different from that of intracranial meningiomas. Treatment of PIMs consists of complete resection, which may be difficult to achieve due to the lack of clear tumor margins on conventional imaging studies. PET/CT using 68Ga-DOTA-conjugated peptides has been used for the diagnosis and treatment planning of different types of meningiomas due to these tracers' affinity to somatostatin receptors, which are found in most meningiomas. However, this imaging modality's use as an intraoperative adjunct has not been reported for PIMs. In this technical note, the authors describe a [68Ga-DOTA0-Tyr3]octreotide (68Ga-DOTATOC)-PET/CT-guided resection of a PIM. In this case, the area of increased uptake in the 68Ga-DOTATOC-PET/CT study extended well beyond the tumor margins identified on MRI. The patient's pathology report confirmed the presence of tumor cells within peripheral bone, which macroscopically appeared normal. The authors propose 68Ga-DOTATOC-PET/CT as a valuable adjunct in the surgical management of PIMs and offer a reasonable justification for its use based on current evidence. Its use for intraoperative image guidance may aid neurosurgeons in achieving a complete resection, thus minimizing the risk of recurrence of this complex pathological entity.

Reconversion of neurosurgical practice in times of the SARS-CoV-2 pandemic: a narrative review of the literature and guideline implementation in a Mexican neurosurgical referral center.

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic has forced the modification of surgical practice worldwide. Medical centers have been adapted to provide an efficient arrangement of their economic and human resources. Although neurosurgeons are not in the first line of management and treatment of COVID-19 patients, they take care of patients with neurological pathology and potential severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here, the authors describe their institutional actions against the pandemic and compare these actions with those in peer-reviewed publications. METHODS: The authors conducted a search using the MEDLINE, PubMed, and Google Scholar databases from the beginning of the pandemic until July 11, 2020, using the following terms: "Neurosurgery," "COVID-19/SARS-CoV-2," "reconversion/modification," "practice," "academy," and "teaching." Then, they created operational guidelines tailored for their institution to maximize resource efficiency and minimize risk for the healthcare personnel. RESULTS: According to the reviewed literature, the authors defined the following three changes that have had the greatest impact in neurosurgical practice during the COVID-19 pandemic: 1) changes in clinical practices; 2) changes in the medical care setting, including modifications of perioperative care; and 3) changes in the academic teaching methodology. CONCLUSIONS: The Instituto Nacional de Neurología y Neurocirugía "Manuel Velasco Suárez" is one of the major referral centers for treating highly complex neurosurgical pathologies in Mexico. Its clinical and neurosurgical practices have been modified with the implementation of specific interventions against the spread of COVID-19. These practical and simple actions are remarkably relevant in the context of the pandemic and can be adopted and suited by other healthcare centers according to their available resources to better prepare for the next event.

Current and future trends in multimodality imaging of coronary artery disease.

Nowadays, there is a wide array of imaging studies available for the evaluation of coronary artery disease, each with its particular indications and strengths. Cardiac single photon emission tomography is mostly used to evaluate myocardial perfusion, having experienced recent marked improvements in image acquisition. Cardiac PET has its main utility in perfusion imaging, atherosclerosis and endothelial function evaluation, and viability assessment. Cardiovascular computed tomography has long been used as a reference test for non-invasive evaluation of coronary lesions and anatomic characterization. Cardiovascular magnetic resonance is currently the reference standard for non-invasive ventricular function evaluation and myocardial scarring delineation. These specific strengths have been enhanced with the advent of hybrid equipment, offering a true integration of different imaging modalities into a single, simultaneous and comprehensive study.