Paraclinoid aneurysms: Outcome analysis and technical remarks of a microsurgical series

Abstract Introduction A critical appraisal of the surgical results of paraclinoid aneurysms is essential in the flow diverters era. This study overviews the data of a three-decade surgical series of paraclinoid aneurysms while focusing on their technical remarks. Methods Overall data of a surgical consecutive series of paraclinoid aneurysms treated between 1993 and 2021 were retrospectively reviewed. Aneurysms were classified according to size and projection. Indications for surgery were different based on the availability of endovascular techniques, especially flow diverter, at the time of treatment. A statistical comparison between ruptured and unruptured aneurysms was accomplished. Results 58 patients were operated upon. Ophthalmic aneurysms were 68%, giant aneurysms 20%, and ruptured aneurysms 45%. Clipping and bypass were executed in 91% and 9% of cases, respectively. An mRS of 0–2 was achieved in 77% of patients, independently by the clinical onset. The mortality rate was 5%. Visual field was improved or unchanged in 71% of elective patients, whereas the incidence of de novo third and sixth cranial nerves deficit was 8% and 5%, respectively. On an average follow-up of 53.3 ± 38 months, a complete and durable aneurysm exclusion was achieved in 91.3% of patients with a single surgery. Conclusions Microneurosurgery is still a valuable treatment option for selected ruptured and unruptured paraclinoid aneurysms. In our experience, it has proven to be definitive and durable, with acceptable morbidity and mortality. Clipping is the treatment of choice in most surgical cases, achieving a good visual outcome in symptomatic patients

Cranio-Orbito-Zygomatic Approach: Core Techniques for Tailoring Target Exposure and Surgical Freedom

The cranio-orbito-zygomatic (COZ) approach is a workhorse of skull base surgery, and each of its steps has a precise effect on target exposure and surgical freedom. The present study overviews the key techniques for execution and tailoring of the COZ approach, focusing on the quantitative effects resulting from removal of the orbitozygomatic (OZ) bar, orbital rim, and zygomatic arch

Therapeutic impact of cytoreductive surgery and irradiation of posterior fossa ependymoma in the molecular era: a retrospective multicohort analysis

PURPOSE: Posterior fossa ependymoma comprises two distinct molecular variants termed EPN_PFA and EPN_PFB that have a distinct biology and natural history. The therapeutic value of cytoreductive surgery and radiation therapy for posterior fossa ependymoma after accounting for molecular subgroup is not known. METHODS: Four independent nonoverlapping retrospective cohorts of posterior fossa ependymomas (n = 820) were profiled using genome-wide methylation arrays. Risk stratification models were designed based on known clinical and newly described molecular biomarkers identified by multivariable Cox proportional hazards analyses. RESULTS: Molecular subgroup is a powerful independent predictor of outcome even when accounting for age or treatment regimen. Incompletely resected EPN_PFA ependymomas have a dismal prognosis, with a 5-year progression-free survival ranging from 26.1% to 56.8% across all four cohorts. Although first-line (adjuvant) radiation is clearly beneficial for completely resected EPN_PFA, a substantial proportion of patients with EPN_PFB can be cured with surgery alone, and patients with relapsed EPN_PFB can often be treated successfully with delayed external-beam irradiation. CONCLUSION: The most impactful biomarker for posterior fossa ependymoma is molecular subgroup affiliation, independent of other demographic or treatment variables. However, both EPN_PFA and EPN_PFB still benefit from increased extent of resection, with the survival rates being particularly poor for subtotally resected EPN_PFA, even with adjuvant radiation therapy. Patients with EPN_PFB who undergo gross total resection are at lower risk for relapse and should be considered for inclusion in a randomized clinical trial of observation alone with radiation reserved for those who experience recurrence

TERT promoter mutations are highly recurrent in SHH subgroup medulloblastoma

Telomerase reverse transcriptase (TERT) promoter mutations were recently shown to drive telomerase activity in various cancer types, including medulloblastoma. However, the clinical and biological implications of TERT mutations in medulloblastoma have not been described. Hence, we sought to describe these mutations and their impact in a subgroup-specific manner. We analyzed the TERT promoter by direct sequencing and genotyping in 466 medulloblastomas. The mutational distributions were determined according to subgroup affiliation, demographics, and clinical, prognostic, and molecular features. Integrated genomics approaches were used to identify specific somatic copy number alterations in TERT promoter-mutated and wild-type tumors. Overall, TERT promoter mutations were identified in 21 % of medulloblastomas. Strikingly, the highest frequencies of TERT mutations were observed in SHH (83 %; 55/66) and WNT (31 %; 4/13) medulloblastomas derived from adult patients. Group 3 and Group 4 harbored this alteration in <5 % of cases and showed no association wit

Therapeutic Impact of Cytoreductive Surgery and Irradiation of Posterior Fossa Ependymoma in the Molecular Era: A Retrospective Multicohort Analysis

Posterior fossa ependymoma comprises two distinct molecular variants termed EPN_PFA and EPN_PFB that have a distinct biology and natural history. The therapeutic value of cytoreductive surgery and radiation therapy for posterior fossa ependymoma after accounting for molecular subgroup is not known

Three-Dimensional Volumetric Assessment of Resected Gliomas Assisted by Horos Imaging Software: Video Case Series of Postoperative Tumor Analyses

Horos (LGPL 3.0; GNU Lesser General Public License, Version 3) is a free, open-source medical image viewer with a user-friendly interface and three-dimensional (3D) volumetric rendering capabilities. We present the use of Horos software as a postoperative tool for residual tumor volume analysis in children with high-grade gliomas (HGG). This is a case series of two pediatric patients with histologically confirmed high-grade gliomas who underwent tumor resection as definitive treatment from June 2011 to June 2019. Volumetric data and extent of resection were obtained via region of interest-based 3D analysis using Horos image-processing software. Horos software provides increased accuracy and confidence in determining the postoperative volume and is useful in assessing the impact of residual volume on outcomes in patients with high-grade gliomas. Horos software is a highly effective means of volumetric analysis for the postoperative analysis of residual volume after maximal safe resection of high-grade gliomas in pediatric patients

Recurrent meningitis associated with frontal sinus tuber encephalocele in a patient with tuberous sclerosis Case report

Tuberous sclerosis complex (TSC) is a genetic neurocutaneous disorder that commonly affects the CNS. The most commonly associated brain tumors include cortical tubers, subependymal nodules, and subependymal giant cell astrocytomas (SEGAs). The authors report an unusual case of recurrent meningitis due to a tuber-containing encephalocele via the posterior wall of the frontal sinus. An 11-year-old girl presented with a history of TSC and previous SEGA resection via interhemispheric approach. She presented twice within 4 months with classic bacterial meningitis. Cerebrospinal fluid cultures revealed Streptococcus pneumoniae. Computed tomography and MR imaging of the brain showed a right frontal sinus encephalocele via a posterior frontal sinus wall defect. Both episodes of meningitis were treated successfully with standard regimens of intravenous antibiotics. The neurosurgical service was consulted to discuss surgical options. Via a bicoronal incision, a right basal frontal craniotomy was performed. A large frontal encephalocele was encountered in the frontal sinus. The encephalocele was herniating through a bony defect of the posterior sinus wall. The encephalocele was ligated and resected followed by removing frontal sinus mucosa and complete cranialization of frontal sinus. Repair of the sinus floor was conducted with fat and pericranial grafts followed by CSF diversion via lumbar drain. Histopathology of the resected encephalocele showed a TSC tuber covered with respiratory (frontal sinus) mucosa. Tuber cells were diffusely positive for GFAP. The patient underwent follow-up for 2 years without evidence of recurrent meningitis or CSF rhinorrhea. This report demonstrates that frontal tubers of TSC can protrude into the frontal sinus as acquired encephaloceles and present with recurrent meningitis. To the authors' knowledge, recurrent meningitis is not known to coincide with TSC. Careful clinical and radiographic follow-up for frontal tubers in patients with TSC is recommended. (DOI: 10.3171/2011.4.PEDS10308

Radiation-associated meningiomas in children: clinical, pathological, and cytogenetic characteristics with a critical review of the literature Clinical article

Object. Radiation-associated meningiomas (RAMs) arise after treatment with radiation to the cranium and are recognized as clinically separate from sporadic meningiomas. Compared with their sporadic counterparts, RAMs are often aggressive or malignant, likely to be multiple, and have a high recurrence rate. However, limited information exists about the clinical, pathological, and cytogenetic features of RAMs in pediatric patients. The authors report the findings in 9 children with meningiomas following therapeutic radiation to the cranium. In addition, they performed a critical review of the English language literature on pediatric RAMs. Methods. Medical tiles were searched for patients who demonstrated meningiomas after a history of radiation to the brain. Only those patients in whom a meningioma occurred before the age of 18 years were included in this study. Clinical and demographic data along with the MIB-1 labeling index and cytogenetic studies were evaluated. Results. The patients consisted of 5 males and 4 females with a median age of 5 years (range 2-10 years) at radiation therapy. The latency period was a median of 10 years after radiation therapy (range 6-13 years). The MIB-1 labeling index was a median of 6.6% (range 4%-10%). Five patients (55.6%) displayed multiple meningiomas at the first presentation. Histological types included clear cell meningioma in I patient, fibroblastic meningioma in 2, chordoid meningioma in 2, meningothelial meningioma in 7 (atypical in 2 cases), xanthomatous meningioma in 1, and chordoid meningioma in 1. Cytogenetic studies showed that the loss of 22q12.2 was the most common abnormality (3 patients), followed by complex cytogenetic abnormalities (2 patients) and rearrangements between chromosomes I and 12 (I patient) and a 1p deletion (1 patient). Conclusions. In contrast to RAMs occurring in adults, those in pediatric patients show an increased incidence of multiplicity on first presentation and unusual histological variants, some of which are described here for the first time. There was no difference in the MIB-1 labeling index in children with RAMs as compared with that in children with non-RAMs. (http//thejns.org/doi/abs/10.3171/2012.7.PEDS1251