Jugular foramen stenosis in external hydrocephalus in infants.

OBJECTIVE: To measure the size of jugular foramina in infants affected by external hydrocephalus (EH) and in a control group, to support the hypothesis that a jugular foramen (JF) stenosis may determine dural venous sinus alterations and increased venous outflow resistance as main pathophysiological factor. METHODS: Minimum, maximum, and mean values of JF areas were measured in a series of phase-contrast magnetic resonance venous angiography (angio MRV PCA3D) performed on 81 infants affected by EH. Results were compared with a group of 54 controls. RESULTS: Smaller JF area was significantly smaller in patients versus controls (43.1 ± 14.6 vs. 52.7 ± 17.8; p < 0.001) resulting in a significantly smaller mean JF areas in patients vs. controls (51.6 ± 15.8 vs. 57.0 ± 18.3; p = 0.043). In patients, smaller JF areas were significantly associated with higher venous obstruction grading score (VOGS) both on the right (p = 0.018) and on the left side (p = 0.005). Positional plagiocephaly (cranial vault asymmetry index > 3.5%) was more frequent among EH patients than controls (38/17) but the difference was not significant (p = 0.07). In the 38 plagiocephalic patients, JF area was smaller on the flattened side than the contralateral in a significant number of cases both in right (21/7) and left (9/1) plagiocephaly (p < 0.0005) as well as the mean area (48.2 + 16.4 mm2 vs. 57.5 + 20.7 mm2, p = 0.002) and VOGS was significantly higher on the plagiocephalic side than on the contralateral side (1.6 ± 1.1 vs. 1.1 ± 0.9, p = 0.019). CONCLUSION: In this series of infants affected by EH, the mean size of the ostium of both JF resulted significantly smaller than controls. JF stenosis was significantly associated with higher degrees of venous obstruction on both sides, suggesting a direct extrinsic effect of JF size on dural sinus lumen and possible consequent effect on venous outflow resistance. Positional plagiocephaly, when present, was associated with a decreased JF area and increased VOGS on the flattened side.

Removal of a thoracic intramedullary epidermoid tumor in a child.

Epidermoid cysts are rare, benign neoplasms that account for less than 1% of all intraspinal tumors. The most common localization is in the lumbar area, and one-third of the tumors are intramedullary. In this video, the authors present removal of a thoracic intramedullary epidermoid tumor in a 6-year-old boy, carrier of a 22q11 gene duplication and affected by psychomotor retardation. He presented a 1-year history of progressive gait impairment. No history of lumbar puncture or trauma was reported. The procedure was performed under neurophysiological monitoring, and it was uneventful with complete recovery of neurological function. Technical nuances are illustrated.

Neuroendoscopy: intraventricular and skull base tumor resection in children.

During the last 30 years, the neurosurgeons have witnessed a revolution in the practice of interventricular surgery. The advent of neuroendoscopy at the end of the 1980s has allowed a minimally invasive management of a very large series of pathologies in pediatric neurosurgery ranging from hydrocephalus to arachnoid cyst to intraventricular tumors. The progresses in the management of hydrocephalus, intracranial cyst, and the fluid filled collection nevertheless has been more rapid and radical due to the simpler equipment that is necessary to perform this kind of surgery. The intraventricular tumors instead have been addressed in a slower way, and for many years, the only endoscopic procedure that was allowed on interventricular tumors was a biopsy associated with the management of hydrocephalus. Only very small tumors have been considered operable for complete removal during many years due to the limitations of the neuroendoscopic equipment and to the small calibers of the working channel. More recently, the advent of new devices and new surgical techniques are offering new perspectives on the possibility of intraventricular tumor surgery in children. In this review, we describe the historical perspective of the learning curve of intraventricular tumor surgery under neuroendoscopic control and try to offer a view of the future perspective in the removal of larger intraventricular tumors, analyzing the main indications for intraventricular endoscopic tumor surgery. We offer as well an historical perspective of the evolution of skull base surgery and endonasal transsphenoidal approach for skull-based tumors in children. This kind of surgery that has acquired widespread acceptance for many pathologies in adult age has diffused more slowly in pediatric neurosurgery due to the anatomical limitation observed in these age range. Also in this field, the slow evolution of the technique and of the technology available to neurosurgeons has allowed a very significant expansion of indication for the minimally invasive removal of skull base tumors in children.

Hemostasis in a giant intraventricular tumor using a saline-cooled radiofrequency bipolar coagulator: technical note.

BACKGROUND: Meningiomas are relatively rare in children and tend to be intraventricular and cystic, with often malignant behavior. Complete excision is associated with the most favorable outcome; moreover, the size and extent of these lesions often make complete excision in one step impossible because of the risk of intraoperative death from uncontrollable hemorrhage. CASE PRESENTATION: A 10-year-old girl was admitted for headache in the last 3 months and was found to have a giant left intraventricular lesion with a volume of 166.63 cm3, which caused hydrocephalus and significant mass effect. Very large draining veins were evident within the tumor, draining into the thalamostriates and internal cerebral veins. Cerebral angiography showed multiple feeders originating mainly from branches of the posterior left choroidal artery with distal afferents that could not be embolized. Therefore, a left parietal transcortical approach was chosen. Given the vascularity of the tumor, saline-cooled radiofrequency coagulation (Aquamantys®) was used to reduce blood loss intraoperatively. Gross total resection (GTR) was achieved with an estimated blood loss of 640 mL. Pathology analysis was consistent with WHO grade 1 transitional meningioma. Postoperatively, the patient was neurologically intact, and MRI confirmed complete resection. CONCLUSION: Aquamantys® is a novel bipolar coagulation device that employs a new bipolar coagulation technique combining radiofrequency energy and saline to achieve hemostatic sealing by denaturing collagen fibers. This offers the possibility of achieving adequate hemostasis even in giant intraventricular tumors in infants to obtain GTR resection with minimal blood loss.

Pure endoscopic ultrasonic removal of choroid plexus papillomas of the third ventricle: technical report of two cases.

BACKGROUND: Tumors of the choroid plexus of the third ventricle are uncommon. Surgical excision is technically challenging because of the rich vascularisation, central location, and high incidence in young children. Open microsurgical resection is considered the standard treatment. However, attempts at purely endoscopic removal of choroid plexus tumors of the third ventricle have also been made in the past, with encouraging results. CASE REPORTS: We report our experience with endoscopic ultrasonic removal of two cases of tumors of the third ventricular choroid plexus. The first case was a large atypical choroid plexus papilloma (WHO grade 2) in the anterior third ventricle associated with hydrocephalus; the second case was a smaller choroid plexus papilloma (WHO grade 1) in the middle/posterior third ventricle without overt hydrocephalus requiring a more anterior neuronavigation guided approach. DISCUSSION AND CONCLUSION: Choroid plexus papillomas of the third ventricle can be safely treated by a purely endoscopic approach because they are usually smaller than their counterparts in the lateral ventricle and often have a recognizable vascular pedicle. Early detection and control of the vascular pedicle at the choroidal border is key to success. The use of ultrasonic aspirator facilitates and expedites endoscopic access. By alternating surface coagulation with fragmentation and aspiration with the ultrasonic aspirator, the tumor can be removed without difficult dissection maneuvers.

Endoscopic ultrasonic aspirator-assisted removal of a third ventricular colloid cyst.

BACKGROUND: Colloid cysts are benign tumors usually located on the roof of the third ventricle. Cyst removal is the treatment of choice. It can be accomplished microsurgically through a transcortical- or transcallosal approach, or endoscopically. There is a lack of consensus regarding the best strategy for cyst removal. One of the challenges of the traditional endoscopic technique is dealing with the cyst content density. Hyperdensity on computed tomography scan and low signal on T2-weighted magnetic resonance imaging (MRI) cyst are correlated with high viscosity cystic content. CASE REPORTS: We present a case of a colloid cyst of the third ventricle in a 15-year-old boy removed through a pure endoscopic transventricular approach. The cyst presented a low signal on T2 MRI; nevertheless, it was easily removed with the help of an endoscopic ultrasonic aspirator. DISCUSSION AND CONCLUSION: The colloid cyst of the third ventricle can be safely treated by a purely endoscopic approach. The rationale of the use of the ultrasonic aspirator relies on the facilitation of aspiration of the content even when the consistency is extremely firm.

Perilesional resection technique of glioblastoma: intraoperative ultrasound and histological findings of the resection borders in a single center experience.

INTRODUCTION: The surgical goal in glioblastoma treatment is the maximal safe resection of the tumor. Currently the lack of consensus on surgical technique opens different approaches. This study describes the "perilesional technique" and its outcomes in terms of the extent of resection, progression free survival and overall survival. METHODS: Patients included (n = 40) received a diagnosis of glioblastoma and underwent surgery using the perilesional dissection technique at "San Gerardo Hospital"between 2018 and 2021. The tumor core was progressively isolated using a circumferential movement, healthy brain margins were protected with Cottonoid patties in a "shingles on the roof" fashion, then the tumorwas removed en bloc. Intraoperative ultrasound (iOUS) was used and at least 1 bioptic sample of "healthy" margin of the resection was collected and analyzed. The extent of resection was quantified. Extent of surgical resection (EOR) and progression free survival (PFS)were safety endpoints of the procedure. RESULTS: Thirty-four patients (85%) received a gross total resection(GTR) while 3 (7.5%) patients received a sub-total resection (STR), and 3 (7.5%) a partial resection (PR). The mean post-operative residual volume was 1.44 cm3 (range 0-15.9 cm3).During surgery, a total of 76 margins were collected: 51 (67.1%) were tumor free, 25 (32.9%) were infiltrated. The median PFS was 13.4 months, 15.3 in the GTR group and 9.6 months in the STR-PR group. CONCLUSIONS: Perilesional resection is an efficient technique which aims to bring the surgeon to a safe environment, carefully reaching the "healthy" brain before removing the tumoren bloc. This technique can achieve excellent tumor margins, extent of resection, and preservation of apatient's functions.

Minimally invasive endoscopic fenestration of a spinal arachnoid cyst in a child with tetrasomy 18p: illustrative case.

BACKGROUND: Spinal arachnoid cysts (SAC) are rare, especially in children. Patients can be asymptomatic or present symptoms of spinal cord compression. In this latter case, surgery is indicated to relieve the compression. Different surgical techniques have been described to treat these cysts, endoscopic or endoscopy-assisted fenestration being the least invasive. Tetrasomy 18p describes the condition in which two copies of the short arms of chromosome 18 are present. It is an extremely rare pathology with a variable phenotype, including 100% of cases cognitive impairment and developmental delay. Different central nervous system (CNS) abnormalities have been found in these patients. OBSERVATIONS: The authors describe the case of a 3-year-old boy with a tetrasomy 18p and a wide spinal arachnoid cyst that received an endoscope-assisted treatment with a significantly improved motor outcome. LESSONS: Tetrasomy 18p is an extremely rare pathology and different CNS abnormalities have been described in association with, but to date spinal arachnoid cyst has never been reported. These children typically show global hypotonia and cognitive impairment. The authors recommend a thorough neurological assessment with cranio-spinal magnetic resonance imaging to rule out any possible malformation that could be improved by surgery.

Exoscope as a Teaching Tool: A Narrative Review of the Literature.

Recently, the emergence of the three-dimensional (3D) exoscope has proven to be a viable alternative to the operative microscope (OM) as a novel workhorse of microneurosurgical procedures. Through its current iteration, the 3D exoscope has been demonstrated to be at least equivalent to the operative microscope in terms of surgical outcomes in many settings. With its superior ergonomics and simplicity of use, the 3D exoscope has been shown in multiple studies to be a powerful visualizing tool during surgical procedures. Moreover, the exoscopic systems, through their current iterations and by means of a high-resolution 3D monitor and 3D glasses, have allowed all participants present in the operative room to attain an unprecedented level of intraoperative visualization of anatomical structures and surgical maneuvers which are traditionally available only to the first operator. Although long-term data are still lacking regarding its future as a replacement of the OM, the 3D exoscope has revealed itself as an intense subject of discussion in neurosurgery regarding its implication for surgical education, especially for residents and junior neurosurgeons. This article is a review of the current state of the literature on the role of the exoscope in surgical education, underlining its strength as a learning tool and its potential future implications in terms of surgical education.