Programmable (proSA®) vs. fixed (SHUNTASSISTANT®) gravitational valves in pediatric patients with hydrocephalus: a 16-year retrospective single-center comparative study with biomechanical analysis.

PURPOSE: In pediatric hydrocephalus (HC) treatment, programmable gravitational valves offer greater flexibility to manage overdrainage during children's growth. However, it remains unclear whether these devices provide better outcomes rather than their precursors. The study assessed the benefit from programmability of gravitational valve, i.e., programmable-SHUNTASSISTANT (proSA®) vs. SHUNTASSISTANT® (SA®). METHODS: Clinical records and imaging of pediatric patients with hydrocephalus of non-tumoral etiology treated with fixed (SA®) or programmable (proSA®) gravitational valves between January 2006 and January 2022 were analyzed in a retrospective single-center study. Valve survival was compared in relation to age and etiology. Lately explanted valves received biomechanical analysis. RESULTS: A total of 391 gravitational valves (254 SA® and 137 proSA®) were inserted in 244 patients (n = 134 males). One hundred thirty-three SA® (52.4%) and 67 proSA® (48.9%) were explanted during a follow-up of 81.1 ± 46.3 months. Valve survival rate at 1 and 5 years with proSA® was 87.6% and 60.6% compared to 81.9% and 58.7% with SA®, with mean survival time 56.4 ± 35.01 and 51.4 ± 43.0 months, respectively (P = 0.245). Age < 2 years at implantation correlated with significantly lower valve survival rates (P < 0.001), while HC etiology showed no significant impact. Overdrainage alone accounted for more SA® revisions (39.8% vs. 3.1%, P < 0.001), while dysfunctions of the adjustment system represented the first cause of valve replacement in proSA® cohort (45.3%). The biomechanical analysis performed on 41 proSA® and 31 SA® showed deposits on the valve's internal surface in 97.6% and 90.3% of cases. CONCLUSION: Our comparative study between proSA® and SA® valves in pediatric HC demonstrated that both valves showed similar survival rates, regardless of etiology but only with young age at implantation. The programmability may be beneficial in preventing sequelae of chronic overdrainage but does not reduce need for valve revision and proSA® valve should be considered in selected cases in growing children older than 2 years.

Heidelberg ETV score to assess success of ETV in patients with occlusive hydrocephalus: a retrospective single-center study.

In aqueduct stenosis, pressure difference below and above level of obstruction leads to bulging of third ventricular floor (TVF) and lamina terminalis (LT). Endoscopic third ventriculocisternostomy (ETV) is the standard treatment in these patients. We tried to assess success of ETV depending on those two radiological changes in aqueduct stenosis. We implemented "Heidelberg ETV score" retrospectively to assess the state of TVF as well as LT in same manner in midsagittal MR image. Every patient had a preoperative, direct, 3-months and one-year postoperative score from -2 to + 2. We correlated the scores to clinical course to decide whether the score is reliable in defining success of ETV. Between 2017-2021, 67 (mean age 25.6 ± 23.9y) patients treated with ETV were included. Success rate of primary and Re-ETVs was 91% over 46.8 ± 19.0 months. A marked shift of score to the left after surgery in success group was noticed through the distribution of score immediate postoperative, 3-months later; 70.2% showed (+ 2) before surgery, 38.9% scored (0) after surgery and 50.9% showed further score drop to (-1) 3 months later, p < 0.001. In cases of failure, there was initial decrease after surgery followed by increase with ETV-failure (mean time to failure: 7.2 ± 5.7 months) in 100%. Significant difference was noticed in Heidelberg score at postoperative 1-year- and failure-MRI follow-up between two groups, p < 0.001. Heidelberg score describes anatomical changes in third ventricle after ETV and can serve in assessment of MR images to define success of the procedure in patients with aqueduct stenosis.

How I do it: intradural anterior petrosectomy.

BACKGROUND: The anterior transpetrosal approach (ATPA) is a cranial base approach for addressing upper petroclival or lateral pontine lesions. It is fundamentally an epidural procedure involving the drilling of the petrous apex. However, this approach has significant procedure-related morbidity, and the surgeon must perform a complete petrosectomy, as the intradural structures are not in view during the drilling. For selected cases, a rationale exists for choosing a tailor-made intradural anterior petrosectomy (IAP). METHOD: This article describes the relevant surgical anatomy and the different surgical steps of the IAP. CONCLUSION: IAP represents a feasible alternative to the standard ATPA with the advantage of minimizing the extent of petrous bone removal to the individual need.

Intracranial arachnoid cysts: What is the appropriate surgical technique? A retrospective comparative study with 61 pediatric patients.

Objective: Symptomatic intracranial arachnoid cysts (ACs) should be treated either through microsurgical (MS) or endoscopic surgical (ES) fenestration. Implantation of cysto-peritoneal shunt (CPS) system is another treatment option with decreasing indication. In our study, we compared the complication and revision rates between the three operative techniques in pediatric patients. Methods: We included patients below 18 years with symptomatic intracranial ACs operated between 2004 and 2021. Initial symptoms, location, complication rate, clinical and radiological improvement, postoperative events and revision rate were compared retrospectively. Results: Sixty-one patients; 33 (54.1%) MS operated (mean age 7.6 years), 18 (29.5%) ES operated (mean age 6.2 years) and 10 (16.4%) with CPS (mean age 3.0 years) were collected. The most common initial symptom was headache in 45.9%. 20 (32.8%) postoperative events were documented. The highest revision rate (60%) was seen in the CPS group compared to 33.3% in MS group and 16.7% in ES group. 31 patients harbored perisylvian ACs, 89% remained event-free after ES, 71% after MS and 20% after CPS. Clinical improvement immediately after surgery was observed in 58 patients (96.9% in MS, 88.9% in ES and 100% in CPS). A radiological volume reduction could be proven postoperative in 51 patients (78.8% MS, 88.9% ES and 90% CPS). Conclusion: Endoscopic fenestration of AC is a safe and efficient technique which is being widely used nowadays with the highest event free survival compared to microsurgical fenestration especially in perisylvian arachnoid cysts. CPS shows on long terms the highest revision rate but carries the least surgical risks.

Initial Clinical Experience and Biomechanical Analysis of a Novel Gravity Unit-Assisted Valve (M.blue) in Pediatric Patients With Hydrocephalus: A Retrospective Study With Two Years of Follow-up.

BACKGROUND: Overdrainage is a widely reported complication representing common indication for shunt revision. Despite recent advances in valve design, repeated shunt revisions represent burden on healthcare systems. OBJECTIVE: To investigate the efficiency of a novel gravity unit-assisted programmable valve "M.blue" in pediatric hydrocephalus using clinical and biomechanical analyses. METHODS: Thisretrospective single-center study included pediatric patients who received M.blue valve between April 2019 and 2021. Several clinical and biomechanical parameters were documented including complications and revision rates. Flow rate, functional assessment in vertical and horizontal positions, and extent of depositions inside valve were analyzed in explanted valves. RESULTS: Thirty-seven M.blue valves in 34 pediatric patients with hydrocephalus (mean age 2.82 ± 3.91 years) were included. Twelve valves (32.4%) were explanted during a follow-up period of 27.3 ± 7.9 months. One-year survival rate of 89% and overall survival rate of 67.6% with a valve survival average of 23.8 ± 9.7 months were observed. Patients with explanted valves (n = 12) were significantly younger, with 0.91 ± 0.54 years of age in average ( P = .004), and showed significantly more adjustments difficulties ( P = .009 ). 58.3% of explanted valves showed deposits in more than 75% of the valve surface despite normal cerebrospinal fluid findings and were associated with dysfunctional flow rate in vertical, horizontal, or both positions. CONCLUSION: The novel M.blue valve with integrated gravity unit is efficient in pediatric hydrocephalus with comparable survival rate. Deposits inside valves could affect its flow rate in different body positions and might lead to dysfunction or difficulties in valve adjustments.