Distance to thrombus, ischemic lesion volume and clinical outcome after thrombectomy for M1 middle cerebral artery occlusion.

BACKGROUND: Stroke resulting from occlusion of the middle cerebral artery (MCA) can have devastating consequences, potentially leading to a loss of independence. This study aimed to investigate the relationship between the distance to the thrombus (DT) and both ischemic lesion volume (ILV) and clinical outcomes. METHODS: We retrospectively evaluated patients with thromboembolic MCA M1 segment occlusion who underwent neurovascular imaging followed by endovascular thrombectomy (EVT) at two comprehensive stroke centers over a 3-year period (2018-2020). Preinterventional computed tomography (CT) or magnetic resonance (MR) angiography was used to measure DT, defined as the distance from the carotid­T bifurcation to the proximal surface of the M1 occlusion. Postinterventional CT or MR imaging was employed to determine the ILV and clinical outcomes were assessed using the modified Rankin scale (mRS) at 3 months. RESULTS: There were 346 patients evaluated. The median DT was 9.4 mm (interquartile range, IQR 6.0-13.7 mm) and the median ILV was 13.9 ml (IQR 2.2-53.1 ml). After adjustment, an increase in DT was associated with a decrease in odds for a larger ILV (odds ratio, OR 0.96, 95% confidence interval, CI 0.92-0.99, p = 0.041). Through this association, more distal thrombi were associated with good clinical outcome (mRS 0-2; clinical outcome available in 282 patients, p = 0.018). The ILV was inversely associated with better clinical outcome OR 0.52 (95% CI 0.40-0.67). CONCLUSION: Based on the findings, DT was identified as an independent albeit weak predictor for ILV and clinical outcomes in patients with MCA M1 occlusion who underwent EVT.

Is location more determining than WHO grade for long-term clinical outcome in patients with meningioma in the first two decades of life?

OBJECTIVE: To identify factors for tumor relapse and poor outcome in patients with meningiomas in the first two decades of life. METHODS: All patients ≤ 21 years of age who underwent resection of a meningioma at the department of neurosurgery, Medical University of Vienna between 1989 and 2022 were included in this retrospective study. Clinical and radiological data were extracted from the medical records. Outcome and tumor relapse were analyzed for tumor location, histological findings and extent of resection. RESULTS: In this study 18 patients were included, 6 meningiomas were located in the skull base, 5 in the convexity and 7 in other locations including intraventricular and spine (2 patients each), falx, intraparenchymal and optic nerve sheath. Most frequent symptoms were seizures and cranial nerve palsy. In total 56% of the meningiomas were World Health organization (WHO) grade 1, 39% grade 2 and 5% grade 3. Gross total resection was achieved in 67%. The overall relapse rate was 61% and 50% underwent repeat surgery. All patients with convexity meningiomas became seizure free and had a favorable outcome. Relapse and clinical outcome were independent of WHO grade among the whole cohort but the outcome significantly depended on the WHO grade when patients with skull base meningiomas were analyzed as a subgroup. The relapse rate was significantly higher in cases of skull base location (100% vs. 42%, p = 0.038) and after subtotal resection (100% vs. 42%, p = 0.038). Clinical outcome was also significantly worse and the rate of complications was higher in patients with skull base meningiomas. CONCLUSION: Patients with convexity meningiomas in the first two decades of life have a good outcome due to high chance of gross total resection. Patients with skull base meningioma are at high risk of relapse and poor outcome, particularly those with WHO grades 2 and 3. Subtotal resection in patients with skull base location is probably the main reason for this difference.

The value of cryoablation in orbital surgery.

Aim of this article is to give an overview of the technical background and the advantages of modern devices for different applications of cryoablation in cranio-orbital neurosurgery.The treatment of orbital lesions is complicated by the complex and potentially inapparent anatomy due to retro-orbital fat. With the help of cryoprobes different well-defined lesions such as cavernous venous malformations can be safely and effectively removed thanks to the cryoadhesive effect. Their use has been described in several different approaches including traditional lateral or transcranial orbitotomy but also anterior transconjunctival as well as transnasal endoscopic approaches. Recently, single-use devices were introduced that allow the use of cryosurgery also without the need for large investment or service costs.

Comparison of minimal detectable protoporphyrin IX concentrations with a loupe device and conventional 5-ALA fluorescence microscopy: an experimental study.

Significance: The 5-aminolevulinic acid (5-ALA) fluorescence technique is now widely applied for intraoperative visualization of specific central nervous system (CNS) tumors. Previous technical implementations of this technique have relied on specifically modified surgical microscopes to visualize intratumoral fluorescent protoporphyrin (PpIX). While this approach evidently allows for reliable intraoperative tumor visualization, it requires the availability of specifically modified surgical microscopes and their use even in cases where the operating neurosurgeon would prefer to use surgical loupes. Recently, a novel loupe device was introduced that is also capable of visualizing 5-ALA fluorescence. Aim: The aim of this study was therefore to compare the detected PpIX concentrations between the conventional fluorescence microscope and the novel loupe device. Approach: We used fluorescence phantoms of different PpIX concentrations for comparison between a conventional fluorescence microscope and the novel loupe device. For this purpose, we created fluorescence images using the excitation light sources of the conventional fluorescence microscope and the loupe device with both available background illumination modes (low and high). Subsequently, the minimal detectable PpIX concentrations according to each technique were determined by five independent neurosurgeons. Results: Using the conventional fluorescence microscope, the median minimal detectable PpIX concentration was 0.16 µg/ml (range: 0.15 to 0.17 µg/ml). By the loupe device, the median minimal detectable PpIX concentration was 0.12 µg/ml (range: 0.10 to 0.12 µg/ml) and 0.08 µg/ml (range: 0.07 to 0.08 µg/ml) for the high- and low-modes, respectively. Altogether, the minimal detectable PpIX concentrations were significantly lower using the loupe device compared to the conventional fluorescence microscope (p=0.007). Conclusions: Our data indicate that the novel loupe device is able to visualize 5-ALA fluorescence with high sensitivity and thus might serve as a powerful tool for visualization of specific CNS tumors in the future.

CD34 microvascularity in low-grade glioma: correlation with 5-aminolevulinic acid fluorescence and patient prognosis in a multicenter study at three specialized centers.

OBJECTIVE: Early markers are urgently needed in low-grade glioma (LGG) evaluation to rapidly estimate the individual patient's prognosis and to determine the optimal postoperative management. Generally, visible 5-aminolevulinic acid (5-ALA) fluorescence is present in only a few LGGs. Recently, the authors identified visible 5-ALA fluorescence as a powerful intraoperative marker for unfavorable outcome in LGG treatment. However, its precise histopathological correlate is unclear. Neoangiogenesis represents a crucial event in tumor evolution, and CD34 is an established marker for vascular endothelial progenitors potentially indicating tumor progression. The aim of this study was thus to correlate 5-ALA fluorescence and CD34 microvascularity as well as to investigate the prognostic value of CD34 in a large series of LGGs. METHODS: In this retrospective study including 3 specialized centers, patients with histopathologically confirmed isocitrate dehydrogenase-mutated LGGs (WHO grade II) receiving 5-ALA prior to resection were included. During surgery, the presence of visible fluorescence was analyzed and one representative tumor sample from the area with the maximum fluorescence effect (tumor with focal fluorescence or nonfluorescing tumor) was selected for each LGG. All fluorescing or nonfluorescing tumor samples were stained for CD34 and semiquantitatively analyzed for microvascular proliferation patterns (physiological vessels, branching capillaries, or microvessel clusters) as well as automatically quantified for CD34 microvessel density (MVD) by standardized histomorphometry software. These semiquantitative/quantitative CD34 data were correlated to the fluorescence status and patient outcome including progression-free survival (PFS), malignant transformation-free survival (MTFS), and overall survival (OS). RESULTS: In a total of 86 LGGs, visible fluorescence was found during surgery in 13 (15%) cases. First, the semiquantitative CD34 score significantly correlated with intraoperative fluorescence (p = 0.049). Accordingly, the quantitative CD34 MVD was significantly higher in tumors showing fluorescence (p = 0.03). Altogether, the semiquantitative CD34 score showed a strong correlation with quantitative CD34 MVD (p < 0.001). At a mean follow-up of 5.4 ± 2.6 years, microvessel clusters in semiquantitative analysis were a prognostic marker for poor PFS (p = 0.01) and MTFS (p = 0.006), but not OS (p = 0.28). Finally, quantitative CD34 MVD > 10 vessels/mm2 was a prognostic marker for poor PFS (p = 0.01), MTFS (p = 0.008), and OS (p = 0.049). CONCLUSIONS: The data indicate that CD34 microvascularity is associated with intraoperative 5-ALA fluorescence and outcomes in patients with LGG. Thus, visible fluorescence in LGGs might indicate increased CD34 microvascularity, serving as an early prognostic marker for unfavorable patient outcome that is already available during surgery.

Endoscopic Treatment of Rathke's Cleft Cysts: The Case for Simple Fenestration.

BACKGROUND: Rathke's cleft cysts (RCC) arise from the pars intermedia because of incomplete regression of the embryologic Rathke pouch. A subset of RCC becomes symptomatic causing headaches, visual and endocrinological disturbances such that surgical intervention is indicated. Several points in surgical management remain controversial including operative strategy (simple fenestration (SF) vs complete cyst wall resection (CWR)) as well as reconstructive techniques. METHODS: A retrospective analysis was conducted of pathologically confirmed RCC operated on by endoscopic endonasal approach from 2006 to 2019. Pre-operative symptoms, imaging characteristics, operative strategy, symptom response, complications and recurrences were recorded. RESULTS: Thirty-nine patients were identified. Thirty-three underwent SF and six underwent CWR. Worsening pituitary function was significantly increased with CWR (50%) compared to SF (3%) (p = 0.008). All patients underwent "closed" reconstruction with a post-operative CSF leak rate of 5% (3% SF vs 16% CWR, p = 0.287). Six (15%) recurrences necessitating surgery were reported. Recurrence rates stratified by surgical technique (18% SF vs 0% CWR, p = 0.564) were not found to be significantly different. CONCLUSIONS: The current series illustrates variability in the surgical management of RCCs. SF with closed reconstruction is a reasonable operative strategy for most symptomatic RCCs cases while CWR can be reserved for selected cases.

The impact of heme biosynthesis regulation on glioma aggressiveness: Correlations with diagnostic molecular markers.

Background: The prognosis of diffusely infiltrating glioma patients is dismal but varies greatly between individuals. While characterization of gliomas primarily relied on histopathological features, molecular markers increasingly gained importance and play a key role in the recently published 5 th edition of the World Health Organization (WHO) classification. Heme biosynthesis represents a crucial pathway due to its paramount importance in oxygen transport, energy production and drug metabolism. Recently, we described a "heme biosynthesis mRNA expression signature" that correlates with histopathological glioma grade and survival. The aim of the current study was to correlate this heme biosynthesis mRNA expression signature with diagnostic molecular markers and investigate its continued prognostic relevance. Materials and methods: In this study, patient data were derived from the "The Cancer Genome Atlas" (TCGA) lower-grade glioma and glioblastoma cohorts. We identified diffusely infiltrating gliomas correlating molecular tumor diagnosis according to the most recent WHO classification with heme biosynthesis mRNA expression. The following molecular markers were analyzed: EGFR amplification, TERT promoter mutation, CDKN2A/B homozygous loss, chromosome 7 + /10- aneuploidy, MGMT methylation, IDH mutation, ATRX loss, p53 mutation and 1p19q codeletion. Subsequently, we calculated the heme biosynthesis mRNA expression signature for correlation with distinct molecular glioma markers/molecular subgroups and performed survival analyses. Results: A total of 649 patients with available data on up-to-date molecular markers and heme biosynthesis mRNA expression were included. According to analysis of individual molecular markers, we found a significantly higher heme biosynthesis mRNA expression signature in gliomas with IDH wildtype (p < 0.0005), without 1p19q codeletion (p < 0.0005), with homozygous CDKN2A/B loss (p < 0.0005) and with EGFR amplification (p = 0.001). Furthermore, we observed that the heme biosynthesis mRNA expression signature increased with molecular subgroup aggressiveness (p < 0.0005), being lowest in WHO grade 2 oligodendrogliomas and highest in WHO grade 4 glioblastomas. Finally, the heme biosynthesis mRNA expression signature was a statistically significant survival predictor after multivariate correction for all molecular markers (p < 0.0005). Conclusion: Our data demonstrate a significant correlation between heme biosynthesis regulation and diagnostic molecular markers and a prognostic relevance independent of these established markers. Consequently, heme biosynthesis expression is a promising biomarker for glioma aggressiveness and might constitute a potential target for novel therapeutic approaches.

Clinico-pathologic predictors of dismal course in atypical meningiomas: a retrospective single-centre analysis.

BACKGROUND: Despite continuous refinement of the WHO classification for meningiomas, the biological behaviour of atypical meningiomas remains difficult to predict on the basis of this grading system alone. The aim of this study was to investigate the prognostic significance of clinical and radiological parameters in a series of atypical meningioma with long follow-up of minimum 5 years. METHODS: Of 1675 meningiomas treated at the Medical University Vienna between 1993 and 2015, 179 were atypical meningioma. Of those, 93 patients were identified with follow-up of ≥5 years. Patients were grouped by recurrence and evaluated for overall and progression free survival as well as potential prognostic parameters such as age, gender, tumor size and location, edema, irregular surface, contrast enhancement, bone invasion and hyperostosis, necrosis, EOR and MIB-1. RESULTS: From 42 (45%) patients in group recurrent and 51 (55%) patients in group nonrecurrent, seven independent factors were associated with decreased progression-free survival in univariate analysis: size ≥5 cm, age ≥60 years, male gender, subtotal resection, irregular surface, and necrosis on magnetic resonance imaging, and MIB-1 ≥6%. In multivariable analysis, only larger size, older age, necrosis and higher MIB-1 remained independent prognostic risk factors for recurrence of atypical meningioma. CONCLUSIONS: We identified larger size, older age, presence of necrosis on magnetic resonance imaging, and higher MIB-1, as detrimental parameters for recurrence of atypical meningioma. Until molecular profiling of atypical meningioma becomes routinely available, these parameters may aid the clinician in decision making about surveillance intervals and adjuvant radiation treatment.

Multiplicity does not significantly affect outcomes in brain metastasis patients treated with surgery.

Background: Brain metastasis quantity may be a negative prognostic factor for patients requiring resection of at least one lesion. Methods: We retrospectively reviewed patients who underwent surgical resection of brain metastases from July 2018 to June 2019 at our institution, and examined outcomes including overall survival (OS), progression free survival (PFS), and rates of local failure (LF). Patients were grouped according to the number of metastases at the time of surgery (single vs multiple). Results: We identified 130 patients who underwent surgical resection as the initial treatment modality. At the time of surgery, 87 patients had only one lesion (control) and 43 had multiple (>1). Two-year OS for the entire cohort was 46%, with equal rates in both the multiple metastases group and the control group (P = .335). 2-year PFS was 27%; 21% in the multiple metastases group and 31% in the control group (P = .766). The rate of LF at 2 years was 32%, with equal rates in both the multiple lesion group and control group (P = .889). On univariate analysis, multiplicity was not significantly correlated to OS (HR = 0.80, 95% CI: 0.51-1.26, P = .336), PFS (HR = 1.06, 95% CI: 0.71-1.59, P = .766) or LF (HR = 1.06, 95% CI: 0.57-1.97, P = .840). Multivariate analysis revealed preoperative tumor volume of the resected lesion to be the single correlate for OS (P = .0032) and PFS (P = .0081). Conclusions: Having more than one metastasis does not negatively impact outcomes in patients treated with surgery. In carefully selected patients, especially those with large tumors, surgery should be considered regardless of the total number of lesions.

DNA Methylation Associates With Clinical Courses of Atypical Meningiomas: A Matched Case-Control Study.

Background: Accounting for 15-20% of all meningiomas, WHO grade II meningiomas represent an intermediate group regarding risk of tumor recurrence. However, even within this subgroup varying clinical courses are observed with potential occurrence of multiple recurrences. Recently, DNA methylation profiles showed their value for distinguishing biological behaviors in meningiomas. Therefore, aim of this study was to investigate DNA methylation profiles in WHO grade II meningiomas. Methods: All patients that underwent resection of WHO grade II meningiomas between 1993 and 2015 were screened for a dismal course clinical course with ≥2 recurrences. These were matched to control cases with benign clinical courses without tumor recurrence. DNA methylation was assessed using the Infinium Methylation EPIC BeadChip microarray. Unsupervised hierarchical clustering was performed for identification of DNA methylation profiles associated with such a dismal clinical course. Results: Overall, 11 patients with WHO grade II meningiomas with ≥2 recurrences (Group dismal) and matched 11 patients without tumor recurrence (Group benign) were identified. DNA methylation profiles revealed 3 clusters-one comprising only patients of group dismal, a second cluster comprising mainly patients from group benign and a third cluster comprising one group dismal and one group benign patient. Based on differential methylation pattern associations with the Wnt and the related cadherin signaling pathway was observed. Conclusion: DNA methylation clustering showed remarkable differences between two matched subgroups of WHO grade II meningiomas. Thus, DNA methylation profiles may have the potential to support prognostic considerations regarding meningioma recurrence and radiotherapeutic treatment allocation after surgical resection.

Postoperative CT scans after resection of brain metastases: neurosurgical routine or added value?

BACKGROUND: Metastasis is the most common brain tumor in adults. It is the standard of care at most North American centers to obtain an early postoperative imaging after their resection. However, the necessity of this practice in the absence of a new postoperative deficit remains unclear. METHODS: We retrospectively reviewed our surgical cohort of patients who underwent resection of brain metastases from July 2018 to June 2019. We collected demographic data and reviewed results of routine postoperative CT scans and neurological morbidities to examine the diagnostic and therapeutic yield of an early postoperative scan. In addition, we performed a systematic review of the topic. RESULTS: Our review included 130 patients, all of whom underwent gross total resection of one or more brain metastases. On postoperative CT, none had unexpected findings such as cavity hematoma or new ischemia; no changes in management resulted from postoperative imaging. One patient required a higher dose of dexamethasone on postoperative day 4 for delayed hemiparesis and aphasia due to cerebral edema. Three additional patients underwent a wound washout for delayed infection during a subsequent admission. Our systematic review identified three additional studies; in a combined cohort of 450 patients (including our own), no patients had clinically actionable findings on routine postoperative CT. CONCLUSIONS: Following resection of brain metastases, a routine postoperative CT scan has low diagnostic yield and did not change patient management in any cases examined in this work.

Triamcinolone acetonide can be detected in cerebrospinal fluid after intratympanic injection.

Intratympanically applied treatments are of increasing interest to the otologic community to treat sudden sensorineural hearing loss or vestibular disorders but also to deliver gene therapy agents, or biologics to the inner ear. Further diversion from the middle ear and perilymph to blood circulation and cerebrospinal fluid via the cochlear aqueduct are one of the limiting factors and so far not understood well enough. In this study, intratympanically applied triamcinolone acetonide was determined in cerebrospinal fluid. Additionally, perilymph was sampled through the round window membrane as well as at the lateral semicircular canal to determine drug levels. Of the twenty-one included patients, triamcinolone acetonide was quantifiable in cerebrospinal fluid in 43% at very low levels (range 0 ng/ml-6.2 ng/ml) which did not correlate with perilymph levels. Drug levels at the two different perilymph sampling sites were within a range of 13.5 ng/ml to 1180.0 ng/ml. Results suggest an equal distribution of triamcinolone acetonide to semicircular canals, which might support the use of triamcinolone acetonide as a treatment option for vestibular pathologies such as Menièrés disease. On the other hand, the distribution to cerebrospinal fluid might be limiting current approaches in gene therapy where a central distribution is unwanted.

Efficacy, Outcome, and Safety of Elderly Patients with Glioblastoma in the 5-ALA Era: Single Center Experience of More Than 10 Years.

BACKGROUND: In the next decades, the incidence of patients with glioblastoma (GBM) will increase due to the growth of the elderly population. Fluorescence-guided resection using 5-aminolevulinic acid (5-ALA) is widely applied to achieve maximal safe resection of GBM and is identified as a novel intraoperative marker for diagnostic tissue during biopsies. However, detailed analyses of the use of 5-ALA in resections as well as biopsies in a large elderly cohort are still missing. The aim of this study was thus to investigate the efficacy, outcome, and safety of surgically- treated GBM in the 5-ALA era in a large elderly cohort. METHODS: All GBM patients aged 65 years or older who underwent neurosurgical intervention between 2007 and 2019 were included. Data on 5-ALA application, intraoperative fluorescence status, and 5-ALA-related side effects were derived from our databank. In the case of resection, the tumor resectability and the extent of resection were determined. Potential prognostic parameters relevant for overall survival were analyzed. RESULTS: 272 GBM patients with a median age of 71 years were included. Intraoperative 5-ALA fluorescence was applied in most neurosurgical procedures (n = 255/272, 88%) and visible fluorescence was detected in most cases (n = 252/255, 99%). In biopsies, 5-ALA was capable of visualizing tumor tissue by visible fluorescence in all but one case (n = 91/92, 99%). 5-ALA administration did not result in any severe side effects. Regarding patient outcome, smaller preoperative tumor volume (<22.75 cm3), gross total resection, single lesions, improved postoperative neurological status, and concomitant radio-chemotherapy showed a significantly longer overall survival. CONCLUSIONS: Our data of this large elderly cohort demonstrate the clinical utility and safety of 5-ALA fluorescence in GBM for improved tumor visualization in both resections as well as biopsies. Therefore, we recommend the use of 5-ALA not only in resections, but also in open/stereotactic biopsies to optimize the neurosurgical management of elderly GBM patients.

Reply to Stummer, W.; Thomas, C. Comment on "Hosmann et al. 5-ALA Fluorescence Is a Powerful Prognostic Marker during Surgery of Low-Grade Gliomas (WHO Grade II)-Experience at Two Specialized Centers. Cancers 2021, 13, 2540".

We greatly appreciate Dr. Stummer's and Dr. Thomas's interest in our study and their important comments [...].

Do standard surgical techniques lead to satisfying aesthetic results in nonsyndromic sagittal suture synostosis?

OBJECTIVE: Surgical correction of synostotic cranial sutures is typically performed early in an affected child's life. Depending on the severity of the cranial synostoses, different aspects of the surgical treatment may have varying degrees of importance. In this sense, the aesthetic appearance in children with normal neurological development in single-suture synostosis plays an important role in self-perception and social acceptance for both the patients themselves and their caregivers. Therefore, in this study, the authors aimed to evaluate the aesthetic outcome after surgical correction in a cohort of patients with nonsyndromic sagittal suture synostosis. METHODS: Between December 2002 and December 2019, a total of 99 patients underwent surgical correction of a synostotic sagittal suture at the Medical University of Vienna. Depending on their age, patients underwent either an extended midline strip craniectomy (EMSC) (< 4 months) or a modified pi procedure (MPP) (≥ 4 months). After the surgical procedure, the outcome was evaluated by the treating neurosurgeon at 1- and 12-month follow-up visits, and after approximately 5 years, before the patient entered elementary school. In addition to that, the patients' caregivers were asked to evaluate the aesthetic outcome of the surgical procedure after 12 months. These results were then compared to evaluate potential differences in the perception of the surgical outcome. RESULTS: After 12 months, the majority of the included patients were evaluated as having a good aesthetic outcome by the treating neurosurgeon (97%) and by their caregivers (89%). These differences did not show statistical significance (p = 0.11). Similarly, no differences in the aesthetic outcome depending on the surgical procedure performed could be found (p = 0.55). At the last follow-up visit, before entering elementary school, all available patients had an excellent or good surgical outcome. Moreover, the majority of caregivers (73%) reported that their child had a normal head shape appearance after surgical correction. CONCLUSIONS: The results of this study have suggested that surgical correction of sagittal suture synostosis by simple operative techniques leads to a good aesthetic outcome and a normal head shape appearance in the majority of patients. An analysis of the evaluation of the surgical outcome by either the treating neurosurgeon or the patient caregivers showed comparable results and, thus, early intervention with simple surgical techniques can be recommended.

5-ALA Fluorescence Is a Powerful Prognostic Marker during Surgery of Low-Grade Gliomas (WHO Grade II)-Experience at Two Specialized Centers.

The prediction of the individual prognosis of low-grade glioma (LGG) patients is limited in routine clinical practice. Nowadays, 5-aminolevulinic acid (5-ALA) fluorescence is primarily applied for improved intraoperative visualization of high-grade gliomas. However, visible fluorescence is also observed in rare cases despite LGG histopathology and might be an indicator for aggressive tumor behavior. The aim of this study was thus to investigate the value of intraoperative 5-ALA fluorescence for prognosis in LGG patients. We performed a retrospective analysis of patients with newly diagnosed histopathologically confirmed LGG and preoperative 5-ALA administration at two independent specialized centers. In this cohort, we correlated the visible intraoperative fluorescence status with progression-free survival (PFS), malignant transformation-free survival (MTFS) and overall survival (OS). Altogether, visible fluorescence was detected in 7 (12%) of 59 included patients in focal intratumoral areas. At a mean follow-up time of 5.3 ± 2.9 years, patients with fluorescing LGG had significantly shorter PFS (2.3 ± 0.7 vs. 5.0 ± 0.4 years; p = 0.01), MTFS (3.9 ± 0.7 vs. 8.0 ± 0.6 years; p = 0.03), and OS (5.4 ± 1.0 vs. 10.3 ± 0.5 years; p = 0.01) than non-fluorescing tumors. Our data indicate that visible 5-ALA fluorescence during surgery of pure LGG might be an already intraoperatively available marker of unfavorable patient outcome and thus close imaging follow-up might be considered.

Clinical Outcome and Technical Nuances After Resection of Orbital Cavernous Venous Malformations-A Single-Center Experience.

BACKGROUND: Cavernous venous malformations (CVMs) represent the most common benign intraorbital lesions. Enlarging or symptomatic CVMs (progressive proptosis or visual disturbances) are treated by surgical resection. For this, a variety of different surgical approaches have been described. The aim of this study was to present a contemporary series of orbital CVMs treated via open microsurgical approaches. METHODS: In this study, patients who underwent resection of orbital CVMs between 2002 and 2019 were included. Presenting symptoms were noted and neuro-ophthalmologic examinations performed pre- and postoperatively. For surgical resection, the location of the orbital CVM and its relation to the orbital anatomy led to decision-making for appropriate approaches. A comparison between anatomical location and surgical outcome was performed. RESULTS: Overall, 35 patients with orbital CVMs were included. Most common presenting symptoms were progressive proptosis (43%) and visual disturbances (34%). Most common location was the lateral quadrant (37%) followed by the superior quadrant (20%). A subfrontal craniotomy was performed in 40% of cases followed by a supraorbital craniotomy including the orbital rim in 34% of cases. For surgical excision, a cryo-probe was used in 30 patients, and complete resection was feasible in all cases. Location of a CVM within the superior quadrant was associated with improved postoperative recovery of visual acuity. No differences for clinical outcomes were observed depending on the surgical approach. CONCLUSIONS: Resection of orbital CVMs is indicated in patients with visual disturbances or progressive proptosis. In these, microsurgical approaches can be used with minimal morbidity for complete removal of these well-circumscribed lesions.

Endoscopic extra-capsular resection of a giant pituitary adenoma: how I do it.

BACKGROUND: Giant pituitary adenomas are characterized by their large size and potential to invade parasellar and suprasellar regions leading to visual decline and hypopituitarism. Thus, they remain a significant surgical challenge, and gross total removal is only achieved in the minority of cases. METHOD: We aim to describe the key surgical steps for endoscopic extra-capsular resection of a giant pituitary adenoma with the aim of achieving complete tumor resection with description of the relevant surgical anatomy, indications and limitations. CONCLUSION: Endoscopic extra-capsular resection of giant pituitary tumors when feasible allows for complete tumor resection, early identification of the gland and avoidance of manipulation of the optic apparatus.

New-onset seizures after cranioplasty-a different view on a putatively frequently observed phenomenon.

BACKGROUND: New-onset seizures after cranioplasty (NOSAC) are reported to be a frequent complication of cranioplasty (CP) after decompressive hemicraniectomy (DHC). There are considerable differences in the incidence of NOSAC and contradictory data about presumed risk factors in the literature. We suggest NOSAC to be a consequence of patients' initial condition which led to DHC, rather than a complication of subsequent CP. We conducted a retrospective analysis to verify our hypothesis. METHODS: The medical records of all patients ≥ 18 years who underwent CP between 2002 and 2017 at our institution were evaluated including incidence of seizures, time of seizure onset, and presumed risk factors. Indication for DHC, type of implant used, timing of CP, patient age, presence of a ventriculoperitoneal shunt (VP shunt), and postoperative complications were compared between patients with and without NOSAC. RESULTS: A total of 302 patients underwent CP between 2002 and 2017, 276 of whom were included in the outcome analysis and the incidence of NOSAC was 23.2%. Although time between DHC and CP differed significantly between DHC indication groups, time between DHC and seizure onset did not differ, suggesting the occurrence of seizures to be independent of the procedure of CP. Time of follow-up was the only factor associated with the occurrence of NOSAC. CONCLUSION: New-onset seizures may be a consequence of the initial condition leading to DHC rather than of CP itself. Time of follow-up seems to play a major role in detection of new-onset seizures.

Cranioplasty following ventriculoperitoneal shunting: lessons learned.

OBJECTIVE: Cranioplasty (CP) is considered as a straightforward and technically unchallenging operation; however, complication rates are high reaching up to 56%. Presence of a ventriculoperitoneal shunt (VPS) and timing of CP are reported risk factors for complications. Pressure gradients and scarring at the site of the cranial defect seem to be critical in this context. The authors present their experiences and lessons learned. METHODS: A consecutive series of all patients who underwent CP at the authors' institution between 2002 and 2017 were included in this retrospective analysis. Complications were defined as all events that required reoperation. Logistic regression analysis and chi-squared test were conducted to evaluate the complication rates according to suspected risk factors. RESULTS: A total of 302 patients underwent cranioplasty between 2002 and 2017. The overall complication rate was 17.5%. Complications included epi-/subdural fluid collection (7.3%) including hemorrhage (4.6%) and hygroma (2.6%), bone graft resorption (5.3%), bone graft infection (2.0%), and hydrocephalus (5.7%). Overall, 57 patients (18.9%) had undergone shunt implantation prior to CP. The incidence of epi-/subdural fluid collection was 19.3% in patients with VPS and 4.5% in patients without VPS, OR 5.1 (95% CI 2.1-12.4). Incidence of hygroma was higher in patients who underwent early CP. Patients with temporary shunt ligation for CP did not suffer from complications. CONCLUSION: CP in patients with a VPS remains a high-risk procedure. Any effort to understand the pressure dynamics and to reduce factors that may trigger the formation of a large epidural space must be undertaken.