Neuroendoscopic access to the third ventricle in patients with narrow foramen of monro without stenosis/obstruction: role of foraminoplasty.

OBJECT: One of the critical steps for the success of intraventricular neuroendoscopic procedures is the entry into the third ventricle and passage of the endoscopy system through the foramen of Monro (FM). A diameter larger than that of the instrument used is considered a prerequisite for safely performing the technique, as damage to this structure can lead to alterations in the fornix and vascular structures. When the foramen diameter is narrow and there is no obstruction/stenosis, the role of foraminoplasty in reducing the risk of complications has not been adequately assessed in the literature. METHODS: A review of endoscopic procedures conducted at our center since 2018 was undertaken. Cases in which preoperative imaging indicated a FM diameter < 6 mm and foraminoplasty technique was applied were examined to determine the technical and functional success of the procedure. The technical success was determined by completing the neuroendoscopic procedure with the absence of macroscopic lesions in the various structures comprising the foramen and without complications in the follow-up imaging tests. Functional success was defined as the absence of cognitive/memory alterations during the 3-month postoperative follow-up. Additionally, a review of the various forms of foraminoplasty described in the literature is conducted. RESULTS: In our cohort, six patients were identified with a preoperative FM diameter < 6 mm without obstruction or stenosis. Foraminoplasty was planned for these cases to facilitate various intraventricular neuroendoscopic procedures. In all instances, the technique was successfully performed without causing macroscopic damage to the structures comprising the foramen. Follow-up visits included various cognitive tests to assess potential sequelae related to microscopic damage to the fornix. None of the patients exhibited anomalies. CONCLUSION: Foraminoplasty in patients with a narrow FM without signs of stenosis/obstruction is a useful technique to reduce the risk of complications during the passage of the endoscopy system through this structure, enabling the safe performance of neuroendoscopic procedures.

Intraventricular Tumors: Surgical Considerations in Lateral and Third Ventricular Tumors.

Management of lateral and third ventricular tumors has been a challenge for neurosurgeons. Advances in imaging and pathology have helped in a better understanding of the treatment options. Technical refinement of microsurgical technique and addition of endoscopy has enabled more radical excision of tumors, when indicated, and added more safety.A proper understanding of the pathology at various ages and treatment options is continuously evolving. Many pediatric tumors are amenable to conservative surgical methods with effective complementary treatments. However, radical surgery is required in many adults as the main treatment and for many benign tumors. Various intraventricular lesions encountered and their surgical management is reviewed here for their efficacy, safety, and outcome, encompassing changes in our practice over the last 20 years.

[Microsurgical ventriculostomy of the third ventricle with access through a burrhole in the treatment of midly located deep-seated brain tumors]. / Mikrokhirurgicheskaya ventrikulostomiya III zheludochka s dostupom cherez frezevoe otverstie v lechenii sredinno raspolozhennykh glubinnykh opukholei golovnogo mozga.

BACKGROUND: Currently, endoscopic third ventriculostomy and simultaneous biopsy of deep midline brain tumors are a generally accepted option in neurooncology. Nevertheless, effectiveness of this surgery and diagnostic accuracy of biopsy are not without drawbacks. An alternative to endoscopic surgery may be simultaneous microsurgical third ventriculostomy and biopsy of deep midline tumors. OBJECTIVE: To evaluate effectiveness and safety of burr hole microsurgical third ventriculostomy in the treatment of deep midline brain tumors. MATERIAL AND METHODS: We used transcortical (25 cases) and transcallosal (8 cases) approaches for microsurgical third ventriculostomy. RESULTS: Initially scheduled biopsy was performed in 19 cases, partial resection in 6 cases, subtotal resection in 4 cases and total resection in 4 cases. All patients underwent microsurgical third ventriculostomy. In 12 cases, stenting of stoma was performed in addition to ventriculostomy. Biopsy was informative in all cases. Postoperative follow-up period ranged from 3 to 44 months (mean 29 months). There was no postoperative hydrocephalus and need for shunting procedure. CONCLUSION: Burr hole microsurgery may be an alternative to endoscopic surgery for the treatment of pineal, periaqueductal and third ventricular tumors.

Ultrasound-guided initial diagnosis and follow-up of pediatric idiopathic intracranial hypertension.

BACKGROUND: Idiopathic intracranial hypertension in children often presents with non-specific symptoms found in conditions such as hydrocephalus. For definite diagnosis, invasive intracranial pressure measurement is usually required. Ultrasound (US) of the optic nerve sheath diameter provides a non-invasive method to assess intracranial pressure. Transtemporal US allows imaging of the third ventricle and thus assessment for hydrocephalus. OBJECTIVE: To investigate whether the combination of US optic nerve sheath and third ventricle diameter can be used as a screening tool in pediatric idiopathic intracranial hypertension to indicate elevated intracranial pressure and exclude hydrocephalus as an underlying pathology. Further, to analyze whether both parameters can be used to monitor treatment outcome. MATERIALS AND METHODS: We prospectively included 36 children with idiopathic intracranial hypertension and 32 controls. Using a 12-Mhz linear transducer and a 1-4-Mhz phased-array transducer, respectively, optic nerve sheath and third ventricle diameters were determined initially and during the course of treatment. RESULTS: In patients, the mean optic nerve sheath diameter was significantly larger (6.45±0.65 mm, controls: 4.96±0.32 mm) and the mean third ventricle diameter (1.69±0.65 mm, controls: 2.99±1.31 mm) was significantly smaller compared to the control group, P<0.001. Optimal cut-off values were 5.55 mm for the optic nerve sheath and 1.83 mm for the third ventricle diameter. CONCLUSIONS: The combined use of US optic nerve sheath and third ventricle diameter is an ideal non-invasive screening tool in pediatric idiopathic intracranial hypertension to indicate elevated intracranial pressure while ruling out hydrocephalus. Treatment can effectively be monitored by repeated US, which also reliably indicates relapse.

A re-evaluation of the Endoscopic Third Ventriculostomy Success Score: a Hydrocephalus Clinical Research Network study.

OBJECTIVE: The Hydrocephalus Clinical Research Network (HCRN) conducted a prospective study 1) to determine if a new, better-performing version of the Endoscopic Third Ventriculostomy Success Score (ETVSS) could be developed, 2) to explore the performance characteristics of the original ETVSS in a modern endoscopic third ventriculostomy (ETV) cohort, and 3) to determine if the addition of radiological variables to the ETVSS improved its predictive abilities. METHODS: From April 2008 to August 2019, children (corrected age ≤ 17.5 years) who underwent a first-time ETV for hydrocephalus were included in a prospective multicenter HCRN study. All children had at least 6 months of clinical follow-up and were followed since the index ETV in the HCRN Core Data Registry. Children who underwent choroid plexus cauterization were excluded. Outcome (ETV success) was defined as the lack of ETV failure within 6 months of the index procedure. Kaplan-Meier curves were constructed to evaluate time-dependent variables. Multivariable binary logistic models were built to evaluate predictors of ETV success. Model performance was evaluated with Hosmer-Lemeshow and Harrell's C statistics. RESULTS: Seven hundred sixty-one children underwent a first-time ETV. The rate of 6-month ETV success was 76%. The Hosmer-Lemeshow and Harrell's C statistics of the logistic model containing more granular age and etiology categorizations did not differ significantly from a model containing the ETVSS categories. In children ≥ 12 months of age with ETVSSs of 50 or 60, the original ETVSS underestimated success, but this analysis was limited by a small sample size. Fronto-occipital horn ratio (p = 0.37), maximum width of the third ventricle (p = 0.39), and downward concavity of the floor of the third ventricle (p = 0.63) did not predict ETV success. A possible association between the degree of prepontine adhesions on preoperative MRI and ETV success was detected, but this did not reach statistical significance. CONCLUSIONS: This modern, multicenter study of ETV success shows that the original ETVSS continues to demonstrate good predictive ability, which was not substantially improved with a new success score. There might be an association between preoperative prepontine adhesions and ETV success, and this needs to be evaluated in a future large prospective study.

Stereotactic anatomy of the third ventricle.

PURPOSE: Endoscopic third ventriculostomy (ETV) is a surgical procedure that can lead to complications and requires detailed preoperative planning. This study aimed to provide a more accurate understanding of the anatomy of the third ventricle and the location of important structures to improve the safety and success of ETV. METHODS: We measured the stereotactic coordinates of six points of interest relative to a predefined stereotactic reference point in 23 cadaver brain hemi-sections, 200 normal brain magnetic resonance imaging (MRI) scans, and 24 hydrocephalic brain MRI scans. The measurements were statistically analyzed, and comparisons were made. RESULTS: We found some statistically significant differences between genders in MRIs from healthy subjects. We also found statistically significant differences between MRIs from healthy subjects and both cadaver brains and MRIs with hydrocephalus, though their magnitude is very small and not clinically relevant. Some stereotactic points were more posteriorly and inferiorly located in cadaver brains, particularly the infundibular recess and the basilar artery. It was found that all stereotactic points studied were more posteriorly located in brains with hydrocephalus. CONCLUSION: The study describes periventricular structures in cadaver brains and MRI scans from healthy and hydrocephalic subjects, which can guide neurosurgeons in planning surgical approaches to the third ventricle. Overall, the study contributes to understanding ETV and provides insights for improving its safety and efficacy. The findings also support that practicing on cadaveric brains can still provide valuable information and is valid for study and training of neurosurgeons unfamiliar with the ETV technique.

Combined Predictive Model for Endoscopic Third Ventriculostomy Success in Adults and Children.

BACKGROUND: The selection of patients in whom endoscopic third ventriculostomy (ETV) can be effective remains poorly defined. The ETV success score (ETVSS) and the presence of bowing of the third ventricle have been identified as independent factors for predicting success, each with limitations. The objective of this study is to elaborate a combined predictive model to predict ETV success in a mixed cohort of patients. METHODS: Demographic, intraoperative, postoperative, and radiologic variables were analyzed in all ventriculostomies performed consecutively at a single institution from December 2004 to December 2022. Qualitative and quantitative measurements of preoperative, immediate, and late postoperative magnetic resonance imaging were conducted. Univariate analysis and logistic regression models were performed. RESULTS: 118 ETVs were performed in the selected period. Of these procedures, 106 met the inclusion criteria. The overall success rate was 71.7%, with a median follow-up of 3.64 years (interquartile range, 1.06-5.62). The median age was 36.1 years (interquartile range, 11.7-53.5). 35.84% were children (median, 7.81 years). Among the 80 patients with third ventricle bowing, the success rate was 88.8% (P < 0.001). Larger third ventricle dimensions on preoperative mid-sagittal magnetic resonance imaging were associated with increased ETV success. The model with the best receiver operating characteristic curves, with an area under the curve of 0.918 (95% confidence interval, 0.856-0.979) includes sex, ETVSS, presence of complications, and third ventricle bowing. CONCLUSIONS: The presence of bowing of the third ventricle is strongly associated with a higher ETV success rate. However, a combined predictive model that integrates it with the ETVSS is the most appropriate approach for selecting patients for ETV.

Usefulness of third ventricle volumetry in patients with normal pressure hydrocephalus.

OBJECTIVE: To use third ventricle morphometric variables as a tool for the selection of patients with idiopathic normal pressure hydrocephalus (iNPH) who are candidates for ventriculoperitoneal shunts (VPS). MATERIAL AND METHODS: Retrospective study enrolling patients with iNPH. Katzman infusion test was performed and a Rout > 12 mmHg/mL/min was considered a positive result. The transverse diameter and the volume of the third ventricle were measured in the preoperative MRI. Postoperative improvement was assessed with the NPH score. The results were analysed with SPSS software. RESULTS: 52 patients with a mean age of 76 years were analysed. There was no difference in the diameter of the third ventricle among patients with a positive result and those with a negative result in the infusion test (12.28 vs 11.68 mm; p = 0.14). Neither were difference detected in the ventricle volume of both groups (3.6 vs 3.5cc; p = 0.66). Those patients who improved after VPS had a smaller third ventricle compared to those who did not respond after surgery (11.85 mm vs. 12.96 mm; p = 0.009). Diameter and volume of third ventricle present a significant strong correlation (Pearson correlation coefficient = 0.72; p < 0.0001). CONCLUSION: Morphometric variables of third ventricle may be useful in predicting a good response to VPS in patients with idiopathic normal pressure hydrocephalus.

Endoscopic third ventriculostomy (ETV) or ventriculoperitoneal shunt (VPS) for paediatric hydrocephalus due to primary aqueductal stenosis.

PURPOSE: The purpose of this study was to compare outcomes of endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt (VPS) in children with symptomatic triventricular hydrocephalus due to primary aqueductal stenosis. METHOD: This is a retrospective analytical study. Patients who underwent either ETV or VPS as the first procedure for hydrocephalus due to primary aqueductal stenosis were included in the study. RESULT: A total of 89 children were included in the study for analysis. The mean age was 8.4 years. Forty-four (49.4%) had their first surgery as ETV and 45 (50.6%) had their first surgery as VPS. Overall, 34 (38.2%) patients required a second surgery (either ETV or VPS) for persistent or recurrent hydrocephalus. The mean follow-up duration was 832.9 days. The overall complication rate was 13.5%. The mean timing of the second surgery after index surgery was 601.35 days. Factors associated with a second surgery were the presence of complications, high protein in cerebrospinal fluid, the relative change of frontal-occipital horn ratio (FOHR) and Evans' index. The survival of the first surgery was superior in ETV (751.55 days) compared to VPS (454.49 days), p = 0.013. The relative change of fronto-occipital horn index ratio (FOIR) was high in the VPS (mean 7.28%) group compared to the ETV (mean 4.40%), p = 0.001 group. CONCLUSION: Overall procedural survival was better after ETV than VPS for hydrocephalus due to aqueductal stenosis. VPS causes more reduction in linear indices of ventricles as compared to ETV, however, is not associated with the success or complication of the procedure.

Dorsum Sellae as Key Landmark in ETV With Disminished Prepontine Cistern: Technical Note and Case Series.

BACKGROUND AND OBJECTIVES: One of the key aspects in the surgical technique of endoscopic third ventriculostomy (ETV) is the perforation of the floor of the third ventricle because of the high risk of injuring vital structures located in that region. According to the standard technique, this perforation should be performed in the midline halfway between mammillary bodies and the infundibular recess to avoid damage to the structures. This can be performed without excessive complications when the diameter of the prepontine cistern is wide. However, in situations where the diameter is reduced (defined in the literature as having a prepontine interval [PPI] ≤1 mm), the probability of complications increases exponentially.In this article, we propose using dorsum sellae as a key point to safely perform ETV in patients with a decreased PPI, guiding the trajectory and its marking using neuronavigation. METHODS: A review was conducted on the latest 100 ETV procedures performed by our team in the past 5 years. The measurement of the PPI was conducted using archived preoperative MRI imaging studies, specifically between the dorsum sellae and the basilar artery. In cases where the PPI was ≤1 mm and, therefore, the use of the dorsum sellae was applied as a reference point, the technical results and procedural functions were documented. RESULTS: In the cohort, 7 patients with a PPI ≤1 mm were identified. In all 7 cases, fenestration of the tuber cinereum was successfully performed without causing vascular damage or associated complications. ETV was successful in 6 patients, with only one experiencing ETV failure necessitating the placement of a ventriculoperitoneal shunt. CONCLUSION: The utilization of the dorsum sellae as a reference point to perform ETV in reduced PPI constitutes a safe alternative to the classical technique.

Third ventricular width by transcranial sonography is associated with cognitive impairment in Parkinson's disease.

BACKGROUND: One-fourth of Parkinson's disease (PD) patients suffer from cognitive impairment. However, few neuroimaging markers have been identified regarding cognitive impairment in PD. OBJECTIVE: This study aimed to explore the association between third ventricular width by transcranial sonography (TCS) and cognitive decline in PD. METHOD: Participants with PD were recruited from one medical center in China. Third ventricular width was assessed by TCS, and cognitive function was analyzed by the Mini-Mental State Examination (MMSE). Receiver operating characteristic (ROC) analysis and Cox model analysis were utilized to determine the diagnostic and predictive accuracy of third ventricular width by TCS for cognitive decline in PD patients. RESULT: A total of 174 PD patients were recruited. Third ventricular width was negatively correlated with MMSE scores. ROC analysis suggested that the optimal cutoff point for third ventricular width in screening for cognitive impairment in PD was 4.75 mm (sensitivity 62.7%; specificity 75.6%). After 21.5 (18.0, 26.0) months of follow-up in PD patients without cognitive impairment, it was found that those with a third ventricular width greater than 4.75 mm exhibited a 7.975 times higher risk of developing cognitive impairment [hazard ratio = 7.975, 95% CI 1.609, 39.532, p = 0.011] compared with patients with a third ventricular width less than 4.75 mm. CONCLUSION: Third ventricular width based on TCS emerged as an independent predictor of developing cognitive impairment in PD patients.

Colloid Cyst: Revision of Third Ventricular Zones for Risk Stratification of Hydrocephalus.

OBJECTIVE: We sought to reclassify the "anatomic risk zones of colloid cysts" as proposed by Beaumont et al, by proposing newer landmarks, and to assess predictive value for the risk of occurrence of hydrocephalus with the new classification compared with the old. METHODS: A retrospective cohort of 122 cases of colloid cyst of third ventricle were categorized into zones 1, 2, or 3 based on Beaumont's classification (old zone) and our classification (new zone) based on radiologic images. We attempted to recategorize these zones by assigning new anatomic landmarks. The difference in zonal distribution of colloid cyst and association with hydrocephalus was studied using the 2 methods of zonal classification. RESULTS: Per the old zone classification, 3/122 patients were in zone 2, whereas 21/122 were in zone 2 per the new zone classification. The new zone method had a higher specificity (36.21% vs. 5.263 %) and positive predictive value (63.37% vs. 54.23%) for occurrence of hydrocephalus in patients with colloid cyst. The Spearman correlation showed better correlation with the new method for occurrence of hydrocephalus (rho = 0.4 [P < 0.00000] vs. 0.2 [P = 0.011]). CONCLUSIONS: Symptomatic colloid cysts are more likely to develop hydrocephalus and sudden acute deterioration. The colloid cyst risk score is a step towards objective decision making, with scope for modification such as the one that we have attempted with new zone classification to achieve superior prognostic ability.

[Chordoid gliomas of the third ventricle]. / Opyt lecheniya khordoidnykh gliom III zheludochka.

BACKGROUND: Chordoid glioma is a rare slow-growing tumor of the central nervous system. Available world experience includes no more than 200 cases (lesion of the third ventricle in absolute majority of cases). Recognition and treatment of chordoid glioma are currently difficult problems due to small incidence of this disease. OBJECTIVE: To describe clinical manifestations and surgical treatment of chordoid glioma of the third ventricle considering literature data and own experience. MATERIAL AND METHODS: There were 12 patients (6 men and 6 women) with chordoid glioma between 2004 and 2023 (10 patients with lesion of the third ventricle, 1 - lateral ventricle, 1 - pineal region). Only patients with tumors of the third ventricle were analyzed. RESULTS: Total and subtotal resection was performed in 1 and 3 cases, respectively. Five patients underwent partial resection, 1 patient underwent biopsy. The follow-up data were available in 7 out of 10 patients (mean 25 months). Radiotherapy was performed in 4 patients (continued tumor growth in 2 cases). One patient died. CONCLUSION: Chordoid glioma is a benign tumor predominantly localized in the third ventricle. Preoperative MRI and CT in some cases make it possible to suspect chordoid glioma and differentiate this tumor from craniopharyngioma, meningioma and pituitary adenoma by such signs as isointense signal in T1WI, hyper- or isointense signal in T2WI, homogeneous contrast enhancement and edema of basal ganglia in T2 FLAIR images. The only effective treatment for chordoid glioma is surgery. Total resection is often impossible or extremely dangerous due to location of tumor, large size and invasion of the third ventricle. Postoperative mental disorders and diabetes insipidus, including severe hypernatremia, are common that requires mandatory monitoring of water and electrolyte balance.

Percutaneous fetal endoscopic third ventriculostomy for severe isolated cerebral ventriculomegaly.

OBJECTIVE: To demonstrate the feasibility and preliminary results of percutaneous fetal endoscopic third ventriculostomy (ETV) in human fetuses (pfETV) with isolated progressive and/or severe bilateral cerebral ventriculomegaly (IPSBV). METHODS: The initial results of pfETV for IPSBV were described. Perioperative, perinatal and postnatal variables were described. The Ages and Stages Questionnaire (ASQ-3), 3rd edition (ASQ-3) was used for follow-up of all infants. RESULTS: Successful pfETV was performed in 10/11 (91%) fetuses, at a median gestational age (GA) of 28.7 weeks (25.3-30.7). There were no perioperative complications. After pfETV, 70% (7/10) of the fetuses had a decreased or stabilized lateral ventricle atria|lateral ventricle's atria. The median GA at delivery was 38.2 weeks (35.9-39.3). There were no perinatal complications. The postnatal ventriculoperitoneal shunt rate was 80% (8/10). Among neonates/infants who had prenatal stabilization or a decrease in the LVAs, 4 (4/7: 57.1%) had abnormal scores on the ASQ-3. Among neonates/infants that experienced prenatal increases in the LVAs, all of them (3/3: 100%) had abnormal scores on the ASQ-3. CONCLUSION: Percutaneous ETV is feasible in human fetuses with progressive and/or severe cerebral ventriculomegaly and seems to be a safe procedure for both the mother and the fetus.

Predicting endoscopic third ventriculostomy success in pediatric shunt dysfunction: a monocentric retrospective case series of 70 consecutive children, systematic review, and meta-analysis.

OBJECTIVE: The outcome of endoscopic third ventriculostomy (ETV) in children who had previously received shunts and who were experiencing shunt dysfunction is still discussed in terms of efficacy (success rate from 40% to 80%) and safety (0%-32.5% of complications). Reported predictive factors of secondary ETV failure are age, early onset of hydrocephalus, and prematurity. The best surgical strategy in the different subgroups of patients with shunt dysfunction is still debated. Therefore, the authors aimed to identify subgroups of patients in whom shunt treatment was associated with favorable outcome of ETV, to define the role of ETV in patients with global rostral midbrain dysfunction syndrome. METHODS: This study was a monocentric retrospective case series and a meta-analysis of children who had previously received shunts and who underwent secondary ETV for shunt dysfunction between 2012 and 2022. Clinical and MRI features were examined, along with surgical outcome, etiology of hydrocephalus, and preoperative ETV Success Score. Univariate and multivariate analyses were performed to find predictors of outcome of secondary ETV. Youden's J index was calculated on age distribution to find an optimal age cutoff. Systematic review of the literature and a meta-analysis were performed according to the PRISMA statement. RESULTS: Seventy consecutive patients were included. The overall success rate of secondary ETV was 63%. Primary obstructive hydrocephalus, age ≥ 36 months, and the presence of aqueductal obstruction were predictors of ETV success. Multivariate analysis found that age < 36 months, primary inflammatory hydrocephalus, and presence of fourth ventricular obstruction were associated with ETV failure. All patients with global rostral midbrain dysfunction syndrome experienced clinical and radiological improvement after ETV. The meta-analysis showed that postinflammatory etiology and age < 36 months were predictors of ETV failure. CONCLUSIONS: ETV is safe and effective for children with obstructive hydrocephalus experiencing shunt dysfunction, notably in cases of primary obstructive hydrocephalus with aqueductal stenosis, and among children whose age was ≥ 36 months who had postinflammatory hydrocephalus.

Achondroplasia Natural History Study (CLARITY): 60-year experience with hydrocephalus in achondroplasia from four skeletal dysplasia centers.

OBJECTIVE: The objective of this study was to describe the incidence and management of hydrocephalus in patients with achondroplasia over a 60-year period at four skeletal dysplasia centers. METHODS: The Achondroplasia Natural History Study (CLARITY) is a registry for clinical data from achondroplasia patients receiving treatment at four skeletal dysplasia centers in the US from 1957 to 2017. Data were entered and stored in a REDCap database and included surgeries with indications and complications, medical diagnoses, and radiographic information. RESULTS: A total of 1374 patients with achondroplasia were included in this study. Of these, 123 (9%) patients underwent treatment of hydrocephalus at a median age of 14.4 months. There was considerable variation in the percentage of patients treated for hydrocephalus by center and decade of birth, ranging from 0% to 28%, although in the most recent decade, all centers treated less than 6% of their patients, with an average of 2.9% across all centers. Undergoing a cervicomedullary decompression (CMD) was a strong predictor for treatment of hydrocephalus (OR 5.8, 95% CI 3.9-8.4), although that association has disappeared in those born since 2010 (OR 1.1, 95% CI 0.2-5.7). In patients born since 1990, treatment of hydrocephalus with endoscopic third ventriculostomy (ETV) has become more common; it was used as the first line of treatment in 38% of patients in the most recent decade. Kaplan-Meier analysis suggests that a single ETV will treat hydrocephalus in roughly half of these patients. CONCLUSIONS: While many children with achondroplasia have features of hydrocephalus with enlarged intracranial CSF spaces and relative macrocephaly, treatment of hydrocephalus in achondroplasia patients has become relatively uncommon in the last 20 years. Historically, there was a significant association between symptomatic foramen magnum stenosis and treatment of hydrocephalus, although concurrent treatment of both has fallen out of favor with the recognition that CMD alone will treat hydrocephalus in some patients. Despite good experimental data demonstrating that hydrocephalus in achondroplasia is best understood as communicating in nature, ETV appears to be reasonably successful in certain patients and should be considered an option in selected patients.

Abnormal clinical presentation and surgical outcome of an intraventricular cavernoma of the third ventricle.

We present a unique case of a man presenting with progressive short-term memory deficits over 10+ years who was found to have a large intraventricular cavernoma in the anterior wall of the third ventricle with invasion of medial limbic structures. Identifying intraventricular cavernomas early is crucial to prevent substantial growth and to increase the chance of successful patient outcomes.

Role of endoscopic third ventriculostomy in patients undergoing resection of pulvinar area lesions: Preliminary clinical results.

BACKGROUND: Patients with pulvinar area lesions may develop hydrocephalus at any stage. The role of endoscopic third ventriculostomy (ETV) in this setting remains unclear. METHOD: We retrospectively enrolled 15 patients with a mean age of 43 years who underwent endoscopic resection of pulvinar area lesions using the supracerebellar infratentorial approach (SCITA). We compared the different modalities of hydrocephalus management and their outcomes. RESULTS: Nine of 15 patients (60.0%) had preoperative obstructive hydrocephalus. Five patients underwent ETV before tumor resection, and none developed postoperative hydrocephalus. Four patients underwent one-stage surgery for tumor removal, and one patient with a polymorphous low-grade neuroepithelial tumor of the young required postoperative ETV. Another patient with diffuse astrocytoma and hydrocephalus underwent concurrent lamina terminalis fenestration and endoscopic resection via the SCITA, which resulted in the resolution of hydrocephalus. The preoperative ETV group had no major postoperative complications, while the non-ETV group had three (0/5 vs. 3/4, P = 0.048). The ETV group also had a shorter intensive care unit stay; however, the difference was not significant (1.2 vs. 2.8; P = 0.188). ETV was effective in alleviating symptoms of postoperative hydrocephalus in patients with midbrain-invading tumors. CONCLUSION: Endoscopic surgery via the SCITA can address both tumor and hydrocephalus issues in some cases but has a higher surgical risk and postoperative hydrocephalus rate. Preoperative ETV can prevent these complications and improve postoperative outcomes.