Transtubular Endoscopic Neuronavigation-Assisted Approach for Extraforaminal Lumbar Disk Herniations: A New Trend for a Common Neurosurgical Disease.

BACKGROUND: Extraforaminal lumbar disk herniations (ELDHs) are relatively rare and are, till today, diagnostic and therapeutic challenges. The transmuscular paramedian approach to the extraforaminal space is today the standard surgical approach. Nevertheless, controlling the correct trajectory to the extruded disk fragment continues to represent a challenge. The application of spinal navigation and spinal endoscopy seems to offer great advantages to ELDH treatment. OBJECTIVE: The purpose of this study is to demonstrate the advantages of spinal navigation for ELDHs by taking a purely endoscopic transtubular approach, focusing on technical aspects and clinical outcomes. METHODS: Nine consecutive patients who underwent a navigation-assisted, muscle-splitting, transtubular, purely endoscopic approach for ELDHs were retrospectively analyzed. Their clinical records were reviewed. Pain evaluations and neurological assessments were conducted. RESULTS: We recorded a notable visual analog scale (VAS) score improvement in postoperative examinations. The mean operation time was 47.05 min. All patients were discharged on postoperative day 1. CONCLUSION: The use of spinal navigation offers a great advantage to ELDH treatment. The aid of navigation allows for a patient-tailored approach and adequate surgical exploration even in face of complex lesion anatomies. The endoscopic transtubular navigated approach seems to offer a significant reduction in operative time, at least in the selected cases.

Predicting the "usefulness" of 5-ALA-derived tumor fluorescence for fluorescence-guided resections in pediatric brain tumors: a European survey.

BACKGROUND: Five-aminolevulinic acid (Gliolan, medac, Wedel, Germany, 5-ALA) is approved for fluorescence-guided resections of adult malignant gliomas. Case reports indicate that 5-ALA can be used for children, yet no prospective study has been conducted as of yet. As a basis for a study, we conducted a survey among certified European Gliolan users to collect data on their experiences with children. METHODS: Information on patient characteristics, MRI characteristics of tumors, histology, fluorescence qualities, and outcomes were requested. Surgeons were further asked to indicate whether fluorescence was "useful", i.e., leading to changes in surgical strategy or identification of residual tumor. Recursive partitioning analysis (RPA) was used for defining cohorts with high or low likelihoods for useful fluorescence. RESULTS: Data on 78 patients <18 years of age were submitted by 20 centers. Fluorescence was found useful in 12 of 14 glioblastomas (85 %), four of five anaplastic astrocytomas (60 %), and eight of ten ependymomas grades II and III (80 %). Fluorescence was found inconsistently useful in PNETs (three of seven; 43 %), gangliogliomas (two of five; 40 %), medulloblastomas (two of eight, 25 %) and pilocytic astrocytomas (two of 13; 15 %). RPA of pre-operative factors showed tumors with supratentorial location, strong contrast enhancement and first operation to have a likelihood of useful fluorescence of 64.3 %, as opposed to infratentorial tumors with first surgery (23.1 %). CONCLUSIONS: Our survey demonstrates 5-ALA as being used in pediatric brain tumors. 5-ALA may be especially useful for contrast-enhancing supratentorial tumors. These data indicate controlled studies to be necessary and also provide a basis for planning such a study.

An unsual symptomatic case of mediastinal myelolipoma treated by VATS approach.

Symptomatic mediastinal location of an extra-adrenal myelolipoma is extremely rare. We describe a 56-year-old female with unusual pain in the right lower posterior chest radiated to the neck and to the upper abdomen. Chest CT showed a lesion of 3.5 x 2.2 cm in the posterior mediastinum. Video-assisted resection was performed and the final pathologic examination revealed the presence of a myelolipoma. Herein we discuss the clinical presentation, the differential diagnosis and treatment of mediastinal myelolipoma.

Differential patterns of NOTCH1-4 receptor expression are markers of glioma cell differentiation.

Background Notch signaling is deregulated in human gliomas and may play a role in their malignancy. However, the role of each Notch receptor in glioma cell differentiation and progression is not clear. We examined the expression pattern of Notch receptors and compared it with differentiation markers in glioma cell lines, primary human cultures, and biopsies of different grades. Furthermore, the effects of a γ-secretase inhibitor (GSI) on cell survival were assessed. Methods Notch receptors and markers of cellular differentiation were analyzed by reverse transcriptase PCR, Western blotting, immunohistochemistry, and immunocytochemistry. GSI sensitivity was assessed in both cell lines and primary cultures grown as monolayers or tumorspheres, by MTT assay. Results In cell lines, Notch1 and Notch2/4 levels paralleled those of glial fibrillary acidic protein (GFAP) and vimentin, respectively. In human gliomas and primary cultures, Notch1 was moderate/strong in low-grade tumors but weak in glioblastoma multiforme (GBM). Conversely, Notch4 increased from astrocytoma grade II to GBM. Primary GBM cultures grown in serum (monolayer) showed moderate/high levels of CD133, nestin, vimentin, and Notch4 and very low levels of GFAP and Notch1, which were reduced in tumorspheres. This effect was drastic for Notch4. GSI reduced cell survival with stronger effect in serum, whilst human primary cultures showed different sensitivity. Conclusion Data from cell lines and human gliomas suggest a correlation between expression of Notch receptors and cell differentiation. Namely, Notch1 and Notch4 are markers of differentiated and less differentiated glioma cells, respectively. We propose Notch receptors as markers of glioma grading and possible prognostic factors.

Spinal neurofibromatosis with central nervous system involvement in a set of twin girls and a boy: further expansion of the phenotype.

BACKGROUND: Familial spinal neurofibromatosis is a form of neurofibromatosis 1 (NF1), consisting of extensive, symmetrical, histologically proven, multiple neurofibromas of the spinal roots at every level and of all major peripheral nerves sometimes associated with typical NF1 stigmata; most cases underlie NF1 gene mutations. OBJECTIVES: The objectives of this study are (1) to report the findings in a set of 16-year-old monozygotic twin girls and a 14-year-old boy and (2) to review the existing literature. METHODS AND RESULTS: In this article, we report the cases of three children who (1) had manifested mildly different symptomatic neuropathy (twins, aged 4 years; and a boy, aged 9 years) associated with massive, symmetrical neurofibromas; (2) had few café-au-lait spots with irregular margins and pale brown pigmentation; (3) were presented with, at brain magnetic resonance imaging (MRI), bilateral, NF1-like high-signal abnormalities in the basal ganglia; (4) yielded missense NF1 gene mutations in exon 39; and (5) had unaffected parents with negative NF1 genetic testing as well as discuss 12 families and 20 sporadic and 5 additional cases that presented spinal neurofibromatosis within classical NF1 families (53 cases) that were reported in the literature. CONCLUSIONS: This article presents the first report on (1) spinal neurofibromatosis in a set of affected monozygotic twins; (2) the earliest onset of the disease; and (3) the occurrence of high signal lesions in the brain at MRI.

Natural history of neurofibromatosis type 2 with onset before the age of 1 year.

Neurofibromatosis type 2 (NF2) with onset before the first year of life has been anecdotally reported in the literature. We (a) prospectively (years 1997-2012) followed up three unrelated NF2 children, all harbouring NF2 gene mutations whose onset of disease was before age 1 year, and (b) systematically reviewed published reports on NF2 in the youngest age group (i.e. onset <1 year). The present three children had (1) small (<1 cm), bilateral vestibular schwannomas (VSs) detected (as an incidental finding) at magnetic resonance imaging (MRI) by the age of 4 to 5 months that were asymptomatic for 10 to 14 years, with sudden and rapid (<12 months) progression in two cases at the age of 11 and 15 years, respectively; (2) development of large numbers of skin NF2 plaques mainly in atypical locations (i.e. face, hands, legs and knees), which reverted to normal skin appearance at the time of VSs progression; (3) lens opacities (n = 1) and NF2 retinal changes (n = 2) detected as early as age of 3-4 months; (4) diffuse (asymptomatic) high signal lesions at brain MRI in the periventricular regions (alike cortical dysplasia); and (5) unaffected first-degree relatives who did not harbour NF2 gene abnormalities. This represents the youngest NF2 group with the longest prospective follow-up so far reported. NF2 may present as a congenital form with bilateral VSs presenting as early as the first months of life and with natural history different to that which occurs in classical NF2.

Dysembryoplastic neuroepithelial tumors: a prospective clinicopathologic and outcome study of 13 children.

Dysembryoplastic neuroepithelial tumors (DNETs) are benign intracortical masses that are typically observed in children and young adults and are classified as glioneuronal tumors (WHO grade I). Large and retrospective series of patients with DNETs have been reported, but prospective studies on pediatric cohorts of patients with DNETs have been lacking. In the present study, 13 children (8 boys, 5 girls; age 8-18 years) who had simple (n = 2) or complex (n = 11) partial seizures (seizure duration range, 2-4 years; mean, 1.5 years; mode, 1.2 years) were prospectively enrolled and monitored over 13 years. The DNETs were located in the frontal (n = 2), temporal (n = 9), or occipital (n = 2) cortex. In 11/13 cases, the seizures were resistant to drug therapy, and all the children had surgery consisting of extended lesionectomy coupled with neuronavigation. Pathology examination revealed cortical dysplasia (n = 8), glial nodules (n = 11), calcification (n = 4), cellular atypia (n = 3), endothelial proliferation (n = 1), perivascular inflammation (n = 3), and meningeal involvement (n = 6). All children were seizure free throughout postsurgical follow-up of 2-11 years. This first prospective study with follow-up monitoring of a childhood population with DNETs confirms, on a long-term basis, that the coupled strategy of extended lesionectomy and neuronavigation has good outcome for long-term seizure control.

Smooth dissection of ligamentum flavum for lumbar microdiscectomy. Preliminary report of this personal technique.

A newly designed technique for preservation of the ligamentum flavum (LF) during the lumbar discectomy is presented. This technique allows the evacuation of the lumbar herniated disk, without removal or laminar disinsertion of the LF. This ligament is smoothly dissected longitudinally in its more lateral portion, obtaining, after discectomy, the contact of the 2 margins with restoration of its functional integrity. Forty-five patients were operated on with this technique. We feel that this technique could offer advantages in reduction of epidural fibrosis and of decreased risk of dural injury, and is helpful to the surgeon in the case of recurrence of discal herniation.

Long-term resolution of acute, obstructive, triventricular hydrocephalus by endoscopic removal of a third ventricular hematoma without third ventriculostomy. Case report and review of the literature.

The authors describe a new extension of the use of neuroendoscopy beyond that which is ordinarily performed. The authors report on the resolution of acute, obstructive, triventricular hydrocephalus in a 42-year-old woman with hypertensive caudate hemorrhage that migrated into the ventricular system. The patient underwent emergency endoscopic removal of a third ventricular hematoma, which was obstructing the orifice of the aqueduct, and restoration of cerebrospinal fluid (CSF) flow but no third ventriculostomy. The authors believe that this is the first such case to be reported. In selected cases of third ventricular hemorrhage, endoscopic removal of the intraventricular hematoma may represent a useful and effective treatment option even in emergency conditions as well as a better alternative to prolonged CSF external ventricular drainage. A reduction in the duration of hospitalization is a beneficial consequence. The authors assert that third ventriculostomy is not always needed.

Primary C1-2, intradural, extramedullary meningeal sarcoma with glial fibrillary acidic protein-immunoreactive components: a spinal gliosarcoma? Case report and review of the literature.

The authors report an exceedingly rare case of a patient harboring a primary, spinal, C1-2, intradural, extramedullary meningeal sarcoma in which there were glial fibrillary acidic protein-immunoreactive components, but, importantly, no physical connection with neural tissue. On initial diagnostic imaging, neuroradiological features suggestive of a spinal meningioma were demonstrated in this 73-year-old man. He underwent a C1-2 laminectomy and removal of the posterior ring of the foramen magnum, and the lesion was excised. Histological and immunohistochemical testing showed a gliosarcoma. The clinical, radiological, and operative data are reviewed, as are the histopathological findings. To the authors' knowledge, this is the first case of a primary spinal intradural extramedullary gliosarcoma reported in the literature.