Fully Endoscopic Supraorbital Approach for Anterior Cranial Base Meningiomas.

BACKGROUND: Anterior cranial base meningiomas include those meningiomas originating from the tuberculum sellae, the planum sphenoidale, or the olfactory groove, with surgical excision being the main treatment modality for these tumors. Conventional microscopic and endoscope-assisted versions of the supraorbital keyhole approach via an eyebrow incision emerged into minimally invasive options that are frequently utilized nowadays for treating these tumors. At the early attempts of endoscope-assisted cranial surgery, it was noted that rigid endoscopes enabled overcoming the problem of suboptimal visualization when small exposures are used. The technical specifications and design of the currently available rigid endoscopes are associated with a group of unique features that define the endoscopic view and lay the basis for its superiority over the microscopic view during brain surgery. Notwithstanding, the fully endoscopic or endoscope-controlled version of the supraorbital keyhole approach is not routinely practiced by neurosurgeons, with few series published so far. In this chapter we elaborate on the surgical technique and nuances of the fully endoscopic supraorbital approach for anterior cranial base meningiomas. METHODS: From a prospective database of endoscopic procedures maintained by the senior author, clinical data, imaging studies, operative charts, and videos of cases undergoing fully endoscopic excision of anterior cranial base meningiomas via supraorbital approach were retrieved and analyzed. The pertinent literature was also reviewed. RESULTS: The surgical technique of the fully endoscopic supraorbital approach for anterior cranial base meningiomas was formulated. CONCLUSION: The fully endoscopic supraorbital approach for anterior cranial base meningiomas has many advantages over the conventional procedures. In our hands, the technique has proven to be feasible, efficient, and minimally invasive with excellent results.

Comparative Optics of the Surgical Microscope and Rigid Endoscopes in Neurosurgery.

This chapter is intended to provide a brief overview of the optics of surgical microscopes and rigid endoscopes, with the aim of providing the reader with the principles dictating the nature of surgical visualization when either of the visual control systems is used. It is not by any means geared toward elaborating on the detailed optical physics of these systems, which is beyond the scope and objective of this chapter.

Fully Endoscopic Resection of Frontal Osteomas.

BACKGROUND: Osteomas are the most common primary bone tumors of the calvaria, with an incidence of less than 0.5%. In skull vault osteomas, the exostotic form that grows from the outer table is more common than the enostotic ones which arise from the inner table and grow intracranially. Osteomas of the forehead are very noticeable and disfiguring; patients usually seek medical advice for cosmetic reasons. Forehead osteomas were traditionally excised via either a direct incision over the lesion using the naturally occurring creases or a conventional bicoronal flap. More recently, endoscopic approaches for excision of forehead osteomas were introduced. The results were very encouraging and the technique was adopted by many groups worldwide yet with many technical variations. In this chapter we elaborate on the surgical technique and nuances of the fully endoscopic resection of frontal osteomas. METHODS: From a prospective database of endoscopic procedures maintained by the senior author, clinical data, imaging studies, operative charts, and videos of cases of forehead osteomas were retrieved and analyzed. The pertinent literature was also reviewed. RESULTS: The surgical technique of the fully endoscopic resection of frontal osteomas was formulated. CONCLUSION: The endoscopic technique has many advantages over the conventional procedures. In our hands, the technique has proven to be less time-consuming, efficient, and minimally invasive with excellent cosmetic results.

Endoscopic Endonasal Surgery for Uncommon Pathologies of the Sellar and Parasellar Regions.

Endoscopic skull base surgery has become an integral part of the present neurosurgical armamentarium. The pioneering efforts in which the purely endoscopic transsphenoidal approach was introduced have triggered a growing tide of using the endoscopic endonasal procedures for a large variety of skull base lesions. Because of their anatomical peculiarities, lesions of the sellar and parasellar regions lend themselves very well to the endoscopic endonasal approaches. Apart from the common pathological entities, many other less frequent pathologies are encountered in the sellar and parasellar area. In this chapter, we review the surgical technique of the endoscopic endonasal transsphenoidal approach and its extensions applied to a variety of rare and uncommon pathological entities involving the sella turcica and clivus. An overview of these pathological entities is also presented and exemplified.

Persisting embryonal infundibular recess (PEIR) and transsphenoidal-transsellar encephaloceles: distinct entities or constituents of one continuum?

Persisting embryonal infundibular recess (PEIR) is a very rare anomaly of the floor of the third ventricle in which the embryonic morphology of the infundibular recess (IR) persists. The exact underlying mechanism of development of PEIR is unknown, and the anomaly has been reported as an isolated finding or in association with other conditions. On the other hand, trans-sphenoidal encephaloceles are the rarest form of basal encephaloceles. The trans-sphenoidal trans-sellar encephalocele (TSE) is the least common variant in which the pituitary gland, pituitary stalk, optic pathways, parts of the third ventricle and IR may be present within the encephalocele. We recently treated one patient with TSE. Based on the observed morphological similarity of the IR in our patient and in the published cases of PEIR, we reviewed the literature in order to validate the hypothesis that PEIR and TSE may possibly belong to one spectrum of malformations. Across the published reports, the morphology of the IR in TSE is very closely similar to PEIR. Moreover, radiological, patho-anatomical, and embryological evidence is in support to our hypothesis that PEIR and TSE are most likely the two extremes of the same continuum of malformations.

Ruptured cerebral pseudoaneurysm in an adolescent as an early onset of COVID-19 infection: case report.

The clinical manifestations of coronavirus disease 2019 (COVID-19) are non-specific and multi-inflammatory. They vary from mild to severe manifestations that can be life-threatening. The association of SARS-CoV-2 infection and pseudoaneurysm formation or rupture of an already existing aneurysm is still unexplored. Several mechanisms may be involved, including the direct destruction to the artery by the viral infection or through the release of the inflammatory cytokines. We are presenting a case of a 13-year-old girl with a ruptured cerebral pseudoaneurysm of the left middle cerebral artery (M2 segment) with severe intracerebral hemorrhage as the earliest manifestation of COVID-19 infection.

Health Care-Associated Infections in a Neurocritical Care Unit of a Developing Country.

BACKGROUND: Health care-associated infections (HAIs) in intensive care units (ICUs) specialized for neurocritical care (neurocritical care units [NCCUs]) are serious yet preventable complications that contribute significantly to morbidity and mortality worldwide. However, reliable data are scarcely available from the developing world. We aimed to analyze the incidence, epidemiology, microbial etiology, and outcomes of HAIs in an NCCU of a tertiary care teaching hospital in a high-income, developing country. METHODS: In this 3-year retrospective cohort study, all patients admitted to the NCCU at the Ibn Sina Hospital in Kuwait for ≥ 2 calendar days were included. Patient demographics, hospitalization, and details of ICU-acquired infections were evaluated. Patient-related outcomes included hospital and ICU length of stay (LOS) and in-hospital mortality. RESULTS: Among 913 patients with a total of 4921 ICU days, 79 patients had 109 episodes of HAIs. The overall incidence rate and incidence density of HAIs were 11.9/100 patients and 22.1/1000 ICU days, respectively. Multiple episodes of infection were documented in 29% of patients. The most prevalent infections were urinary tract infections (UTIs; 40/109 [37%]), bloodstream infections (30/109 [28%]), and pneumonia (16/109 [15%]). Seventy-six percent of infections were device-associated infections. A total of 158 pathogens were isolated, of which 109 were Gram-negative bacteria. Of the 40 Gram-positive bacteria, 22 were staphylococci. Seven infections were due to Clostridium difficile. There were 15 Staphylococcus aureus isolates, 47% of which were methicillin resistant. Two episodes of UTIs were due to Candida species. There were 84 Enterobacteriaceae isolates, 24% of which were extended-spectrum ß-lactamase producers. All Pseudomonas aeruginosa isolates were susceptible to aminoglycosides and carbapenems. Klebsiella species were the most common pathogen (45/158 [28%]), causing pneumonia (11/33 isolates [33%]), bloodstream infections (12/37 isolates [32%]), and UTIs (16/52 isolates [31%]). One episode of bloodstream infection was due to multidrug resistant Acinetobacter baumanii which was susceptible only to colistin. Only pneumonia was independently associated with mortality, while all HAIs that occurred were significantly associated with a prolonged ICU LOS. CONCLUSIONS: This is the first HAI surveillance study in an NCCU in Kuwait, and our results demonstrate the burden of HAIs on the neurologically injured patient, regardless of the site of infection. The high prevalence and resistant profile of HAIs in an NCCU in a developing country relative to a developed country has important implications for patient safety and emphasizes the need to strengthen collaboration between NCCU teams and infection control teams to prevent serious complications in this setting.

Pseudotumoral Encephalic Schistosomiasis: A Literature Review.

Pseudotumoral encephalic schistosomiasis (PES) is the chronic form of cerebral neuroschistosomiasis, and is rarely encountered in clinical practice. Clinically, PES closely resembles other intracranial space-occupying lesions including brain tumors. Laboratory investigations are usually inconclusive, and neuroradiologic findings are frequently reported as non-specific. Such diagnostic difficulties may result in delayed diagnosis and treatment. Across the literature, there is a paucity of information about and controversy over many aspects of the disease. Particularly, inconsistent magnetic resonance imaging (MRI) findings, a wide variation of medical treatment protocols, lacking consensus regarding the indications of surgery, and undetermined information regarding the impact of the extent of resection on prognosis. We herein review the pertinent literature with the aim of providing focused information regarding the pathogenesis of PES, its currently identified more distinctive neuroimaging features, and the indications and extent of surgery in light of the state-of-the-art operative neurosurgical practice. A distinctive multinodular arborizing pattern of PES lesions can often be observed on MRI in patients with PES. Praziquantel is considered by many authors to be the drug of choice in all cases, and seems to be effective at variable dose regimens. Although lesion excision utilizing current technology is generally safe, the indications and extent of surgery are still undetermined and should be decided on a case-by-case basis. Multicenter collaborative research is further needed to fill the existing gaps in the current knowledge on PES.

Does establishing a neurovascular unit improve the outcome after surgical clipping for aneurysmal subarachnoid hemorrhage? Results from a 5-year observational study in Kuwait.

BACKGROUND: Failure to prevent rebleeding after cerebral subarachnoid hemorrhage (SAH) is the most frequent reason for high morbidity and mortality of aneurysmal SAH. Our study aims to identify the outcome after surgical clipping of aneurysmal SAH before and after the establishment of the neurovascular unit. The clarifications of the positive turnover in the outcome will be discussed. METHODS: A retrospective cohort analysis was carried out on our experience with a controlled group of patients who underwent clipping for ruptured cerebral aneurysms (n = 61) from January 2015 to December 2019. A modified Rankin scale (mRS) was used to determine the outcome after 6 months of follow-up. RESULTS: The median mRS score (i.e., outcome) on admission was 4, whereas it was with a median score of 2 six months after clipping (P ≤ 0.001). Overall, the cases with a good outcome were 63.9% of the sample, while the poor outcome conditions were 36.1%. The most cases with an improved outcome were after introducing the neurovascular unit, representing a transition of aneurysmal clipping practice in our center. The good outcome was changed from 42% to 76.7%, and the poor outcome was changed from 58% to 23.3% (P = 0.019). The crude mortality rate was similar to the rate worldwide (18%), with a noticeable decrease after organizing a neurovascular subspecialty. CONCLUSION: The outcome after clipping of ruptured SAH can be largely affected by the surgeon's experience and postoperative intensive care. Organizing a neurovascular team is one of the major factors to achieve good outcomes.

Monoclonal antibodies as a preventive therapy for migraine: A meta-analysis.

Calcitonin gene-related peptide (CGRP) antagonists have recently grabbed the attention of clinicians for migraine prophylaxis. The present meta-analysis aimed to assess the efficacy and safety of CGRP monoclonal antibodies (mAbs) in patients with chronic and episodic migraine using a systematic therapeutic regimen. More specifically, double-blind placebo-controlled randomized clinical trials (RCTs) which assessed the therapeutic potential of monthly subcutaneous injections were included. The primary outcomes entailed changes in monthly migraine days (MMDs) and treatment-related adverse events (TRAEs) for: Erenumab 70 mg, fremanezumab 225 mg, and galcanezumab 120 mg. No eligible studies have investigated eptinezumab. A total of 13 RCTs were eligible (6979 patients, 84.81% females, 42.94% received active medications). Compared to placebo, the selected doses of mAbs reduced the MMDs significantly after four weeks (mean difference [MD] -2.07, 95% CI -2.47 to -1.66, P < 0.001), eight weeks (MD -1.78, 95% CI -2.26--1.49, P < 0.001), and 12 weeks (-1.80, 95% CI -2.16 to -1.43, P < 0.001). These effects remained significant with each individual medication across all treatment cycles. In addition, the number of days using acute migraine medications decreased and the proportion of 50% responders increased significantly with mAbs use compared to placebo. No significant differences between groups were noted in TRAEs. CGRP mAbs provide highly efficacious and safe outcomes which start early after the first injection. The tolerability of these medications surpasses that of other small-molecule CGRP antagonists.

Effect of Sphenoid Sinus Pneumatization on the Surgical Windows for Extended Endoscopic Endonasal Transsphenoidal Surgery.

BACKGROUND: Little is known on the impact of the pattern and extent of pneumatization of the sphenoid sinus (SS) on the dimensions of the surgical windows used in extended endoscopic endonasal transsphenoidal approaches. We therefore investigated whether the distances between the 2 optic canals and between the paired paraclival carotid arteries are influenced by the pattern and extent of pneumatization of the SS. METHODS: One hundred high-resolution computed tomography scans from 47 adult female and 53 adult male patients were analyzed. The pattern of SS pneumatization was classified into conchal, presellar, and sellar types. Sellar-type sinuses were then classified according to a newer detailed classification system. Maximal anteroposterior (AP), transverse (TR), and craniocaudal diameters of the SS, interoptic distance at the limbus sphenoidale (IODL) and at the entrance of the optic canal (IODE) and the intercarotid distance between the paraclival carotids (ICD) were measured. A 2-tailed Mann-Whitney U test and Pearson correlation coefficient (R) were used for statistical analysis. A P value <0.05 was considered statistically significant. RESULTS: Positive correlation was found between IODL and both AP and TR diameters of the SS; between IODE and both AP and TR diameters of the SS; and between ICD and all diameters of the SS. The highest correlation for each of the IODL, IODE, and ICD was noted with the TR diameter of the SS. CONCLUSIONS: During the development of the SS, pneumatization progress likely exerts quantitative and direction-specific forces, which gradually increase the interoptic and intercarotid distances.

Endoscopic Endonasal Excision of Large and Giant Pituitary Adenomas: Radiological and Intraoperative Correlates of the Extent of Resection.

BACKGROUND: Despite the superb visualization offered by the endoscopic endonasal transsphenoidal approach, the resection rates of large and giant pituitary adenomas have remained much lower than those of smaller macroadenomas. Various tumor characteristics can influence the extent of resection (EOR) and have been variably reported. Additional understanding of these factors is mandatory to improve the results. We analyzed the radiological and intraoperative tumor characteristics influencing the EOR in a cohort of patients with large and giant pituitary macroadenomas undergoing endoscopic endonasal transsphenoidal excision under our care. METHODS: Twenty-eight patients were included. Magnetic resonance images were retrospectively analyzed for pre- and postoperative tumor volumetric analysis; preoperative tumor volume calculation using the formula (A × B × C/2); preoperative radioanatomical characteristics, including tumor shape, radiological structure, contrast enhancement, and extension; and the EOR. Intraoperative data were retrieved and included. RESULTS: The preoperative calculated tumor volume was 38.14 ± 23.02 cm3 and the preoperative measured tumor volume was 50.345 ± 17.36 cm3. A statistically significant difference was found between the calculated and measured tumor volumes for the whole cohort and for tumors with a maximum diameter >3.9 cm. A statistically significant difference in the EOR was found at a volume threshold of 26.2 cm3. Large cysts, heterogeneous enhancement, Knosp grade ≤2, soft tumor consistency, and tumor hemorrhage were significantly associated with gross total resection. CONCLUSIONS: Volumetric analysis should replace 2-dimensional methods in determining the size of large and giant pituitary adenomas. Specific tumor characteristics were associated with the EOR and could help in predicting the EOR for these tumors.

Assessing classifiers from two independent data sets using ROC analysis: a nonparametric approach.

This paper considers binary classification. We assess a classifier in terms of the Area Under the ROC Curve (AUC). We estimate three important parameters, the conditional AUC (conditional on a particular training set) and the mean and variance of this AUC. We derive, as well, a closed form expression of the variance of the estimator of the AUC. This expression exhibits several components of variance that facilitate an understanding for the sources of uncertainty of that estimate. In addition, we estimate this variance, i.e., the variance of the conditional AUC estimator. Our approach is nonparametric and based on general methods from U-statistics; it addresses the case where the data distribution is neither known nor modeled and where there are only two available data sets, the training and testing sets. Finally, we illustrate some simulation results for these estimators.