Explore the vast range of titles available.

IntroductionStereotactic brain biopsies are essential for obtaining tissue samples from brain lesions, crucial for comprehensive histological analysis and subsequent adjuvant therapies. While most biopsies target supratentorial lesions, those involving the posterior fossa are less frequent but pose significant technical and surgical challenges, necessitating careful patient management.MethodsWe present our experience with stereotactic biopsies of the posterior fossa using the Leksell Vantage frame (Elekta, Stockholm, Sweden) and the ZD Inomed frame (Inomed Medizintechnik GmbH, Emmendingen, Germany). For the ZD frame, we either mounted it upside down or employed a frontal approach, while for the Leksell Vantage frame, we utilized a reverse x-axis orientation. Planning was based on 3-T MRI scans and preoperative MRI merged with stereotactic CT for coordinate generation.ResultsFrom 2006 to 2023, we performed 25 stereotactic biopsies of the posterior fossa in our department—9 with the ZD Inomed frame and 16 with the Leksell Vantage frame. The cohort included 14 male and 11 female patients, with an average age of 60.6 years (range 36—80 years). The average surgery duration was shorter with the Leksell Vantage frame (32.6 min vs. 44.8 min, p = 0.05). The average length of the planned trajectory was 41.7 mm for the Leksell Vantage frame and 52.2 mm for the ZD Inomed frame. Postoperativ bleeding occurred in two cases—one managed conservatively, the other required surgical intervention. Additionally, two other cases presented new postoperative focal neurological deficit. The overall mortality rate was 34.8% and a 40-day postoperative mortality rate of 13.0%.ConclusionOur experience demonstrates that stereotactic biopsies of lesions in the posterior fossa can be effectively managed with different frame systems, though they present a higher degree of complexity. Notably, the Leksell Vantage frame was associated with a significantly shorter surgery duration. This technical note provides valuable insights and detailed technical guidance for neurosurgeons facing similar challenges.

PurposeTo investigate how different presentations of posterior fossa arachnoid cysts (PFACs) influence surgical indication and strategies and their impact on clinical and radiological outcome in children, proposing a treatment flow-chart.MethodsIn this retrospective study, children < 14 years old with PFAC diagnosed at IRCCS Giannina Gaslini Hospital from 2008 to 2023 were identified Patients showing a mega cisterna magna (MCM), Dandy-Walker syndrome (DWS), Blake’s pouch cyst (BPC), neuroenteric cysts or multiple cysts were excluded. Data regarding type of treatment, age at surgery, surgical complications were collected and analyzed. Clinical and radiological outcomes were considered at 1-, 3- and 5-years follow-up.ResultsA “wait and see” strategy in asymptomatic showed better clinical outcomes at 1-year follow-up (p = 0.047). No significant difference in clinical outcome or risk of re-surgery were observed between microsurgical fenestration, endoscopical fenestration or shunting were reported, while location of the cyst influenced surgical strategy (p = 0.015). Age < 12 months at surgery (p = 0.008), hydrocephalus (p = 0.001), especially when associated with macrocephaly (p = 0.004), and the placement of a shunt (p = 0.006) resulted as risk factors of re-surgery. An association between radiological and clinical outcomes was observed at 1-year follow-up.ConclusionTreatment decision should be based on clinical presentation rather than radiological presentation. While a “wait and see” strategy is suggested in asymptomatic patients, when surgery is indicated, several factors should be considered, such as presence of hydrocephalus, location of the cyst and age of the patient, to improve clinical outcomes, reducing complications.

Objective To explore the correlation between posterior fossa crowding and the occurrence of classical trigeminal neuralgia (TN). Methods A total of 60 patients diagnosed with classical TN and 60 age- and sex-matched healthy volunteers were included as a control group for a case-control study. All subjects underwent high-resolution 3D magnetic resonance imaging (MRI) examinations (including 3D-FIESTA and 3D-TOF MRA sequences). The original data were subjected to 3D reconstruction and measurement of posterior fossa volume (PFV) and hindbrain volume (HBV) using 3D-slicer software. The posterior fossa crowding index (PFCI) was calculated as HBV/PFV × 100%. Finally, data were analyzed using SPSS 22.0 statistical software. Results The average PFCI in patients with TN was 85.0% ± 3.9%, compared to 82.7% ± 3.9% in the control group, with a significant statistical difference ( P  = 0.025). Female patients with TN had a more crowded posterior fossa than male patients (86.4% ± 3.8% vs. 83.4% ± 3.4%, P  = 0.033). Multiple linear regression analysis showed that a higher PFCI was associated with being female ( P  = 0.022), younger age ( P  = − 0.003), and being a patient with TN ( P  = − 0.023). Conclusion Patients with PTN have a more crowded posterior fossa compared to the healthy control group. A higher PFCI is associated with being female, younger age, and being a patient with TN. Posterior fossa crowding may be a risk factor for neurovascular conflict (NVC), making it more likely to lead to the occurrence of TN.

Background The pathogenesis of Chiari malformations is incompletely understood. We tested the hypothesis that different etiologies have different mechanisms of cerebellar tonsil herniation (CTH), as revealed by posterior cranial fossa (PCF) morphology. Methods In 741 patients with Chiari malformation type I (CM-I) and 11 patients with Chiari malformation type II (CM-II), the size of the occipital enchondrium and volume of the PCF (PCFV) were measured on reconstructed 2D-CT and MR images of the skull. Measurements were compared with those in 80 age- and sex-matched healthy control individuals, and the results were correlated with clinical findings. Results Significant reductions of PCF size and volume were present in 388 patients with classical CM-I, 11 patients with CM-II, and five patients with CM-I and craniosynostosis. Occipital bone size and PCFV were normal in 225 patients with CM-I and occipitoatlantoaxial joint instability, 55 patients with CM-I and tethered cord syndrome (TCS), 30 patients with CM-I and intracranial mass lesions, and 28 patients with CM-I and lumboperitoneal shunts. Ten patients had miscellaneous etiologies. The size and area of the foramen magnum were significantly smaller in patients with classical CM-I and CM-I occurring with craniosynostosis and significantly larger in patients with CM-II and CM-I occurring with TCS. Conclusions Important clues concerning the pathogenesis of CTH were provided by morphometric measurements of the PCF. When these assessments were correlated with etiological factors, the following causal mechanisms were suggested: (1) cranial constriction; (2) cranial settling; (3) spinal cord tethering; (4) intracranial hypertension; and (5) intraspinal hypotension.

Background Prenatal diagnoses of cystic malformations of the posterior fossa mainly encompass arachnoid cysts, Blake’s pouch cysts and Dandy-Walker syndrome. To date, vermian cysts have not been reported prenatally. Objectives To report a series of fetuses with a vermian cyst. Materials and methods This was a single-center retrospective study conducted from 2012 to 2021. We included all fetuses presenting with a vermian cyst and excluded all other types of posterior fossa cyst. The cyst was visible at prenatal ultrasound (US) and/or magnetic resonance imaging (MRI). Postnatal imaging and/or clinical outcome data were available. Results Sixteen fetuses fulfilled the inclusion criteria with a strong female predominance ( n =13). US and MRI were performed at a mean gestational age of 29+5 and 33+1 weeks, respectively. In all patients, the cyst was in the vermian horizontal fissure. The mean longest dimension was about 10 mm. The vermis and other posterior fossa structures were otherwise normal. At postnatal imaging, 13 children underwent brain imaging including 11 MRIs with complete regression ( n =9), stability ( n =1) and increase in size ( n =3) of the cyst. Psychomotor development was normal in 14 children. One child (with an inner ear malformation) showed a slight delay in walking and language acquisition. Slight walking ataxia was present in another child. Conclusion We report 16 fetuses with posterior fossa cysts located within the vermis at the level of the horizontal fissure, diagnosed at US and/or MRI and carrying an overall excellent neurological prognosis.

The sphenoid bone is an unpaired bone that contributes to the formation of the skull base. Despite the enormous progress in transnasal endoscopic visualisation, imaging techniques remain the cornerstones to characterise any pathological condition arising in this area. In the present review, we offer a bird’s-eye view of the developmental, inflammatory, and neoplastic alterations affecting the sphenoid body and clivus, with the aim to propose a practical diagnostic aid for radiologists based on clinico-epidemiological, computed tomography, and magnetic resonance imaging features.

We report the case of a 63-year-old man with a midline posterior fossa tumor and peculiar imaging features where we were unsure of the nature of the lesion preoperatively. Histopathology revealed it to be a craniopharyngioma. It appeared to arise from the inferior medullary velum, a site not described before in the literature. The previous four cases mentioned in literature and speculations on the origins in this uncommon site are discussed.

Gross total resection (GTR) is the mainstay therapy for chordomas and chondrosarcomas to have the best prognosis. The aims of this study were to specify the limits of EEA, emphasize the need for additional combined approaches for tumors beyond these limitations for high resection rates, discuss the prognostic factors and operative nuances that affect GTR, and present the causes and characteristics of early and late recurrences. We retrospectively analyzed the endoscopic endonasal surgeries in the Pituitary Research Center and Neurosurgery Department of the Kocaeli University Faculty of Medicine, Turkey between January 2004 and December 2019. We retrospectively reviewed the medical data, radiological images, and surgical videos of patients, and 72 patients with chordoma and chondrosarcoma were included in the study. Based on pathology reports, 72 patients (seven pediatric) were identified, to whom 91 endoscopic operations were performed. We determined the surgical limitations for each clival segment as superior, middle, and inferior. Then, we divided these into three subgroups according to whether the tumor shows dural invasion (extradural chordoma, large extradural - minimal intradural component, and minimal extradural - large intradural component). The tumors of 19 (26.4%), 25 (26.4%), and nine (12.5%) patients originated from the superior, middle, and inferior clivus, respectively. Nineteen (26.4%) patients had panclival involvement. GTR was performed in 47 (65.3%) the patients. The GTR rate in patients with panclival tumors was 47.3% (9/19). The experience, lateralization, dural involvement, and origin of the clivus affecting GTR were analyzed. Extradural – intradural extensions were verified as negative predictor factors for GTR, whereas tumors located in the superior (OR: 16.710, p=0.030) and middle (OR: 11.154, p=0.023) segments were positive predictive factors for GTR. An increasing experience in endoscopic surgery significantly increases the GTR rates by widening the surgical limitations. Due to dense bone infiltration and adhesion to critical neurovascular structures, recurrence rates are high despite performing GTR. Although surgery and adjuvant treatments improve the 5-year survival of patients, the mortality rates remain high. Therefore, surgery of these tumors should be performed by experienced centers. In addition to surgical and adjuvant therapies, targeted molecular and translational biological therapies are also needed for chordomas and chondrosarcomas in the future. •Chordomas and chondrosarcomas are locally aggressive, pathologically benign tumors.•Bone infiltration and anatomical adhesions affect resection rates.•Endoscopic approach is the most effective surgery for clival lesions.•But it has limitations and additional combined surgery should be required.•Reasons for rapid recurrence on chordomas are still not clearly understood.

Background Penetrating injuries to the posterior cranial fossa are extremely rare. Perforating skull injuries are also not frequently recorded, with only ten cases reported in the literature. Combining these two factors, this case report presents a patient with a perforating head injury at the posterior cranial fossa caused by an iron rod and shares the clinical management of this rare case. Case presentation An 18-year-old Vietnamese male construction worker was admitted following a 3-m fall from scaffolding due to an occupational accident. Upon admission, the patient was conscious, hemodynamically stable, and no neurological deficits or other associated injuries were detected. A 1-m-long, 0.8-cm-diameter iron rod had penetrated from the left neck to the right occipital region. Owing to the size of the foreign body, only an X-ray was performed. The patient underwent emergency surgery to remove the foreign object and manage the damaged brain tissue. Intraoperatively, a contusion of the right cerebellar hemisphere with a complex dural tear, subarachnoid hemorrhage, and multiple small metallic fragments was found, with no spinal cord or major vessel injuries. Postoperatively, the patient recovered well. After 3 years of follow-up, the patient had excellent results and returned to normal daily activities. Conclusions The optimal surgical approach should be carefully planned, especially in cases where preoperative computed tomography imaging is challenging. It is recommended to plan the direction of foreign body extraction and limit the use of artificial materials.

Purpose While 84% of patients surgically treated for Chiari malformation type 1 (CM1) demonstrate improved quality of life after posterior fossa decompression surgery, there are many risks associated with this surgery. Surgical planning to identify candidates likely to improve postoperatively may benefit from an improved understanding of morphological changes after decompression surgery. To evaluate these changes, we quantified 59 morphological parameters on 42 CM1 adult female patients before and after CM1 decompression surgery. Methods Fifty-nine morphological parameters in the posterior cranial fossa, cranio-cervical, and intracranial regions in the midsagittal plane were evaluated using 42 T1-weighted magnetic resonance images of female CM1 patients before and after surgery, and 42 healthy female controls. Morphological differences before and after surgery were compared through the development of a technique to establish the opisthion location, a key reference point not present after surgery. Results In addition to the expected reduction of the cranio-caudal dimension of the cerebellum, objective analyses showed a significant increase in the area of the cerebrospinal fluid spaces, posterior (6×) and inferior (2.6×) to the cerebellum (+ 112 ± 102 and + 140 ± 127 mm 2 , respectively). This increased area was primarily impacted by an average reduction in the occipital bone length of 24.5 ± 7.3 mm following surgery. Based on multiple angles, results demonstrated a 2°–4° anterior rotation of the cerebellum after surgery. Conclusion Our results show that decompression surgery results in significant changes in the cerebellum and cerebrospinal fluid spaces. Further investigation should determine how these morphological changes impact clinical outcomes.