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76. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie

Prof. Dr. med.

Vorsitz | Chair

Slit-valve mechanism in middle cranial fossa arachnoid cyst: case series and literature review

Hydrocephalus

Slit-valve-Mechanismus bei Arachnoidalzysten der mittleren Schädelgrube: Fallserie und Literaturübersicht

Arachnoid cysts are well-demarcated, space-occupying lesions filled with cerebrospinal fluid. While many remain asymptomatic, they can cause a range of neurological symptoms when they exert pressure on surrounding brain structures. The most accepted theory for AC formation involves the slitting of the arachnoid with sequestration of CSF, though the expansion mechanism remains debated. This slit-valve mechanism is the main focus of this study.A retrospective analysis of adult and paediatric patients who underwent endoscopic treatment for middle cranial fossa arachnoid cysts under the guidance of the senior author between January 1993 and June 2024 was conducted. In addition, a literature review was performed.A total of 131 patients with intracranial arachnoid cysts underwent 139 endoscopic procedures. Among them, 61 patients had arachnoid cysts located in the middle cranial fossa. Surgical videos were available for review in 44 cases. Intraoperatively, a pulsatile membrane covering the middle cerebral artery, forming a slit-valve mechanism, was observed in 31 patients (70.45%). From 61 screened literature articles, 11 met inclusion criteria, detailing 244 cases of slit-valve mechanisms in arachnoid cysts. Most cysts were located suprasellar, with endoscopic treatment being predominant.The slit-valve mechanism offers significant insights into the dynamic behaviour and expansion of arachnoid cysts. Recognizing these mechanisms is crucial for accurate diagnosis and effective surgical management, enhancing our understanding of the pathophysiology of arachnoid cysts and guiding clinical care.

Abstractvortrag | Abstract talk

Dr. med.

PD Dr. med.

Neurocognitive effects of CSF biomarkers in idiopathic normal pressure hydrocephalus patients undergoing VP Shunt placement

Neurokognitive Effekte von Liquor-Biomarkern bei Patienten mit idiopathischem Normaldruckhydrozephalus unter VP-Shunt Therapie

Idiopathic normal pressure hydrocephalus is an increasingly prevalent neurodegenerative condition among the elderly, characterized by the Hakim triad. Accurate diagnosis and prognosis are essential since the symptoms can be reversible with appropriate treatment, such as VP-shunt surgery. This study investigates the relationship between cerebrospinal fluid biomarkers, particularly Tau, Phospho-tau, the beta-amyloid ratio (Aβ42/Aβ40), and neurocognitive outcomes post-surgery.Eighty patients diagnosed with iNPH who underwent shunt placement between November 2021 and July 2023 were included. A comprehensive neuropsychological test battery was administered before, one hour after, and one day after lumbar puncture, and six weeks and three months post-surgery. CSF samples were analyzed for tau, phospho-tau and the beta-amyloid ratio. Neuropsychological tests assessed various cognitive functions, including executive functions, psychomotor speed, language, and memory.Patients with a higher beta-amyloid ratio showed significant cognitive improvement post-surgery. Neuropsychological tests, such as the DemTect and Trail Making Test A & B indicated enhanced performance over time, particularly at the three-month follow-up. Conversely, the MMSE did not show significant improvement. The data suggest that the beta-amyloid ratio is a potential prognostic marker for positive neurocognitive outcomes following VP-shunt surgery.The beta-amyloid ratio (Aβ42/Aβ40) is a valuable biomarker for distinguishing iNPH from Alzheimer's disease and predicting cognitive improvement post-surgery. Patients with higher ratios exhibited better neurocognitive outcomes, emphasizing the importance of comprehensive neuropsychological assessments. These findings support the potential of personalized treatment strategies based on biomarker analysis to optimize patient selection and improve outcomes for iNPH patients undergoing VP-shunt surgery.

Cerebrospinal fluid shunt valve malfunctions: mechanical failures or user error?

Ventilfehlfunktionen bei Liquorshunts: mechanische Probleme oder Anwenderfehler?

Advances in cerebrospinal fluid shunt valve technology have come a long way in recent years. Not only have adjustments of valve settings become easier for example, but we also see lower rates of complications like over- or underdrainage. Malfunctions of shunt valves due to mechanical failures are supposed to be rare. Here we present data of explanted shunt valves from patients with shunt systems who underwent surgery because of a supposed valve dysfunction, which were sent to the manufacturer for identifying the cause for malfunction.Between 2014 and 2024 a total of 25 analysis reports from the manufacturer of explanted shunt valves were available for evaluation. Those were received and stored electronically. Causes of valve malfunction as supposed by the clinician were compared to those identified by the manufacturer.Overall, 19 valves were explanted from children, 6 from adults. Valves included 11 Miethke proGAV, 12 Miethke proGAV 2.0, 1 Miethke proSA and 1 Miethke GAV 2.0. The two prevalent causes for supposed valve dysfunction in children were failure to adjust the valve setting (9/19 valves) and valve occlusion (9/19 valves). Failure to adjust the valve setting was confirmed from the manufacturer in 7/9 cases, in two cases due to deformation of the valve, and in 5 due to protein debris. Occlusion was confirmed in 5/9 cases. The prevalent cause for supposed valve dysfunction in adults was failure to adjust the valve setting (4/6 valves). Only in 2 cases a valve defect resulting in failure to adjust the valve setting was confirmed by the manufacturer, due to protein debris.The most prevalent cause for a mechanical valve malfunction in our study was protein debris resulting in failure to adjust the valve setting. Deformation of valves due to user error was only shown in two cases. Furthermore, the fact that most of the explanted valves were from children with post-hemorrhagic hydrocephalus might suggest that protein debris is still a challenge for modern shunt valve technology.

Increasing Incidence of Normal Pressure Hydrocephalus in Germany: An Analysis of the Federal Statistical Office Database from 2005 to 2022

Steigende Inzidenz des Normaldruckhydrozephalus in Deutschland: Eine Analyse der Datenbank des Statistischen Bundesamts von 2005 bis 2022

Normal pressure hydrocephalus (NPH) is a reversible cause of gait disturbances and dementia in the elderly, posing diagnostic and therapeutic challenges. In Germany, the epidemiology and surgical management of NPH are not well understood. This study aimed to characterise epidemiological trends and evaluate surgical management strategies for NPH in Germany.A retrospective nationwide population-based study of NPH cases in Germany from 2005 to 2022 was conducted using data from the German Federal Statistical Office. Parameters assessed included incidence trends, demographic characteristics, and surgical interventions.A total of 118,526 NPH diagnoses were recorded, with 29,662 surgical interventions. The population-adjusted incidence of NPH increased by 48%, from 5.4 to 8.0 cases per 100,000 individuals (p < 0.001), peaking in 2018. The largest increases were seen in the "80-89" age group, followed by the "70-79" and "90+" age groups. Surgical interventions increased by 8.4% (p < 0.001), with ventriculoperitoneal shunt being the predominant procedure.The study highlights a 48% rise in NPH incidence in Germany from 2005 to 2022, particularly affecting the elderly. There was also an increase in surgical interventions, underscoring the need for prioritising NPH in national healthcare research agendas.

Rapid communication

Continuous telemetric measurement of intracranial pressure assessing the effect of different body position maneuvers, activity and time

Kontinuierliche telemetrische Messung des intrakraniellen Drucks zur Evaluation der Auswirkungen verschiedener Körperpositionen, Aktivität und der zeitlichen Korrelatio

Non-invasive intracranial pressure measurements using a telemetric sensor (tICP) in shunted and non-shunted patients can give new insight into patients" symptoms, help to further understand pathophysiologies and be used to optimize valve settings in shunted patients. However, so far, continuous tICP measurements (ctICP) along with body position and activity are hampered by limited technical options. Using a novel reader unit prototype for the M. Scio in this pilot study ctICP recordings assessing the effect of different body position maneuvers and activity were performed to evaluate the temporal correlation of intracranial pressure, body position and activity.For this prospective study, we established a standardized protocol of different body positions (lying, sitting, walking, climbing stairs). ctICP measurements were performed for up to 25min. An ICP analysis software (ICPicture, Miethke, Germany) was used for detailed evaluation of the collected data with depiction of ICP changes, amplitude (AMP) and the temporal correlation.The patient group consisted of 5 adult patients (median age: 37.2y; range 24–52y). Among these were 4 shunted and 1 non-shunted patient (stand-alone - SA) who received a shunt after SA measurements and CSF tap test. Underlying pathologies were idiopathic intracranial hypertension (IIH, n=4) and suspected functional aqueductal stenosis. After connectivity check, ctICP showed robust continuous recordings. ctICP recordings clearly demonstrated a significant, direct ICP response in all patients changing from lying to sitting as well as lying to standing position, while no difference in the AMP was found. Further, no relevant difference in ICP or AMP between sitting or standing position was detected. The overall highest AMP values were found during activity. Position related ICP and AMP changes were more pronounced in the SA patient compared to the shunted patients.ctICP recording is warranted to further understand the pathophysiology of CSF disturbances. In our pilot study we established a protocol for ctICP and showed robust measurements and direct effects of body position and activity on ICP and AMP. ctICP provides new opportunities to obtain objective data to develop a better understanding and optimize treatment strategies. Further research with ctICP in a larger cohort comprising variable pathologies are necessary to validate and integrate this approach into clinical practice.

Prof. Dr.

SOPHYSA Polaris Valves in hydrocephalus treatment: long-term follow up study in a group of 325 children and adults

Das SOPHYSA Polaris Ventil in der Hydrocephalusbehandlung: Langzeitverläufe in einer Gruppe von 325 Kindern und Erwachsenen

There are still many open questions about the selection of valve systems for hydrocephalus treatment and the evaluation of treatment results. Our study deals with the SOPHYSA Polaris Valve as an example of an adjustable system as there are only scattered reports about this so far in the literature. Special focus is also put on the ongoing question of clinically relevant over- and underdrainage.In a retrospective long-term follow up study, we collected data from 325 consecutive patients treated in our department who received a SOPHYSA Polaris Valve. No patients were excluded. Outcome were shunt revisions, infections and shunt survival followed by the evaluation of clinical results including initial valve settings and subsequent adjustment procedures and their effect.The whole patient group included 259 adults and 66 children (mean age 52,8 yrs and 5,3 yrs). According to the length of follow-up (< 5 yrs and >5 yrs) 4 groups were defined, maximum follow-up extended up to 15,5 yrs. Adult patient group: leading etiology pressure hydrocephalus, revision rate 37,1%, infections 10,8%, 5-years valve survival rate 79,9%, postoperative improvement after shunting 90,1%. Surgery due to overdrainage: 6,8%/6,3% (follow-up < 5yrs/>5 yrs), underdrainage 0,7%/13,5% (follow-up< 5yrs/>5yrs). Group of children: leading etiology posthemorrhagic hydrocephalus , revision rate 63,5%, infections 10,6%, 5-years valve survival rate 81,6%, postoperative improvement after shunting 84,3%. Surgery due to overdrainage 2% and underdrainage 25,5%. Both groups: 304 valve adjustments were done, 196 due to underdrainage and 108 due to overdrainage. Adjustment was followed by clinical improvement in 72,1% (adults) and 89,6% (children). No valve adjustment was done in 24/51 children and 36/111 adult patients with a follow up >5 yrs. A MIETHKE shuntassistant was used in 6 patients and a SPV 400 valve was used during a revision in 4 patients with overdrainage symptoms.According to our results an adjustable system like the SOPHYSA Polaris Valve is adequate for different etiologies of hydrocephalus in all age groups. Underdrainage is found more frequently than overdrainage, in addition to valve adjustment procedures gravitational components were needed in a small group (N=6). In a reasonable number of patients no changes of pressure settings were needed, this offers a perspective for the use of fixed-pressure systems depending on socio-economic conditions.

Session 32
Hydrocephalus

Termin

Vorsitz | Chair

Thema

Programm

Session 32Hydrocephalus

Termin

Vorsitz | Chair

Thema

Programm

Session 32
Hydrocephalus