Background Diagnostic criteria for idiopathic intracranial hypertension (IIH) rely partly on lumbar puncture opening pressure, which may not capture the dynamic pressure-volume properties of the craniospinal system. Lumbar infusion testing (LIT) enables multidimensional assessment of cerebrospinal fluid dynamics during controlled volume loading. We characterized LIT-derived physiological variability in pediatric IIH and explored its association with longitudinal optical coherence tomography (OCT) outcomes. Methods This retrospective single-center study included 21 pediatric patients with IIH diagnosed according to the Friedman criteria between 2023 and 2026. LIT-derived measures of pressure response, apparent cerebrospinal fluid outflow resistance, pressure-volume reserve, pulsatility, and slow-wave activity were analyzed. Principal component analysis (PCA) was performed on 20 complete-case infusion studies. The first principal component was interpreted as a continuous pressure-volume reserve score and evaluated as an exploratory predictor of longitudinal global retinal nerve fiber layer thickness (RNFL G) and ganglion cell complex thickness (GCC). Results Mean age at diagnosis was 9.07 ± 4.52 years. Median baseline and plateau intracranial pressures were 19.69 mmHg [IQR 15.62–23.85] and 32.99 mmHg [26.12–35.41], respectively. The first two principal components explained 70.93% of total variance. PC1 accounted for 45.95% and contrasted greater compliance and pressure-amplitude coupling with higher plateau pressure, higher apparent outflow resistance, and a steeper infusion slope, defining a continuous pressure-volume reserve axis. OCT follow-up was available in 20/21 patients. In the pre-surgical RNFL model, PC1 and the time-by-PC1 interaction were significant, indicating steeper RNFL reduction over time toward the lower-reserve end of the axis. This interaction was not significant in the smaller postoperative subgroup, and GCC findings did not show a consistent longitudinal interaction. Conclusions Pediatric IIH demonstrated marked LIT-derived physiological heterogeneity organized predominantly along a continuous pressure-volume reserve axis rather than by baseline pressure alone. The association between this axis and pre-surgical RNFL trajectories suggests that multiparametric LIT may provide clinically relevant physiological information beyond opening pressure. Prospective studies with standardized LIT and OCT protocols are required to validate these findings.

The AKT2-related hypoinsulinemic hypoglycemia and overgrowth syndrome was initially described over 30 years ago as MORFAN syndrome which was an acronym for Mental retardation, pre- and post-natal Overgrowth, Remarkable Face, and Acanthosis Nigricans. Despite the limited possibility of confirming a diagnosis on the molecular level at that time, a comprehensive 30-year follow-up of a patient facilitated a detailed exploration of the syndrome's clinical trajectory. This article presents a case report spanning three decades, highlighting the significance of detailed clinical follow-up in understanding and studying this unique syndrome. Although initially associated with intellectual deficiency, the patient's intellectual abilities remain largely within the normal range. Neuropsychological examinations revealed selective neurocognitive impairment, with a predominant disruption in psychomotor speed and executive functions. Molecular genetic examination confirmed a pathogenic variant in the AKT2 gene, associated with impaired insulin metabolism and increased tumorigenesis risk. Neurooncological assessments revealed intracranial meningiomatosis, emphasizing the syndrome's potential oncological implications. Surgical interventions addressed various complications, including meningiomas and renal hamartomas. The presented case offers valuable insights into the long-term natural history of AKT2-related hypoinsulinemic hypoglycemia and overgrowth syndrome, suggesting the importance of regular oncological surveillance due to its predisposition to tumorigenesis, thereby providing clinical considerations for future cases based on long-term follow-up experience.

Hearing preservation is a key goal of vestibular schwannoma (VS) microsurgery. Intraoperative auditory monitoring spans far-field auditory brainstem responses (ABR)/brainstem auditory evoked potentials (BAEP) and near-field cochlear nerve action potentials (CNAP)/dorsal cochlear nucleus action potentials (DNAP). Prior reports often conflate diagnostic accuracy of thresholds with interventional effectiveness. We separated these domains to deliver decision-relevant synthesis. PRISMA-guided systematic review of PubMed, ScienceDirect, and Embase. Eligible VS studies used ABR/BAEP, CNAP, or DNAP and reported (1) diagnostic performance of prespecified intraoperative thresholds versus postoperative hearing, or (2) comparative effectiveness of monitoring-guided surgery. Primary clinical outcome: long-term serviceable hearing (GR I–II or AAO-HNS A–B). ROBINS-I for effectiveness and QUADAS-2 for diagnostic studies were used for risk of bias assessment. Random-effects models were used for synthesis. The study was registered at PROSPERO (CRD420251181366) before its start. We included 34 studies yielding 1,297 patients with operated VS (27 diagnostic/threshold; 7 comparative-effectiveness). The two nonrandomized cohorts comparing any intraoperative auditory monitoring versus none were directionally favorable but imprecise (RR 1.28, 95

Abstract Objective Facial nerve dysfunction is a common complication after vestibular schwannoma (VS) resection. Traditional grading scales such as House-Brackmann (HB), Sunnybrook, and Fisch are subjective and prone to inter-rater variability. Emotrics, a computer vision–based tool, offers objective facial analysis, but its role in neurosurgical populations remains underexplored. Methods Patients undergoing VS surgery were prospectively enrolled in this study. Standardized frontal facial photographs were taken preoperatively, at discharge, and at three-month follow-up. Emotrics quantified facial symmetry and movement across static, dynamic, and synkinesis domains. Composite scores were generated and compared with clinical grading scales and patient characteristics. Results Thirty-six patients (mean age 51.2 ± 12.3 years) were included. Emotrics detected significant improvement in dynamic function (mean score: 0.41 at discharge vs. 0.56 at 3 months, p < 0.01) and synkinesis (0.62 to 0.51, p < 0.05); static symmetry remained stable. Strongest correlations with clinical grading were found at discharge and 3 months. Discharge Emotrics total scores correlated significantly with HB ( r = –0.883, p < 0.001), Sunnybrook ( r = 0.892, p < 0.001), and Fisch ( r = 0.883, p < 0.001). At 3 months, dynamic scores remained strongly associated with HB ( r = –0.799), Sunnybrook and Fisch ( r = 0.790; p = 0.001). Worse Emotrics outcomes were linked to older age (62.1 vs. 48.6 years, p = 0.04) and larger tumor volume (8.2 vs. 4.5 cm 3 , p = 0.03). Conclusions Emotrics offers objective assessment of facial nerve function, correlates well with clinical scales, and enhances evaluation of dynamic facial recovery. Its integration may refine postoperative monitoring and guide rehabilitation.

Over recent decades, various hypotheses and theoretical frameworks have been advanced to elucidate the aetiology of normal pressure hydrocephalus (NPH). This reversible neurological condition, characterised by the classical clinical triad of gait disturbance, urinary incontinence and cognitive impairment, represents a multifactorial interplay of pathophysiological processes that co-occur, rather than originating from a single, defined cause. Despite extensive research efforts, the precise aetiology and underlying pathophysiological pathways remain indeterminate. Contributory factors such as dysfunction of the glymphatic system, diminished arterial pulsatility, metabolic and osmotic dysregulation, astrogliosis and neuroinflammatory processes are acknowledged as critical in the pathogenesis of NPH. Recent advancements in the understanding of these pathophysiological aberrations have substantially refined the conceptualisation of the NPH phenotype, enhancing the predictive accuracy for cerebrospinal fluid diversion interventions. This review addresses the definition and classification of NPH and emphasises future research directions aimed at further elucidating the molecular and physiological mechanisms underlying the disease. A comprehensive understanding of this syndrome is critical for informed clinical decision-making and optimising therapeutic outcomes. With the global increase in ageing populations, accurately differentiating NPH from other neurodegenerative disorders and managing overlapping comorbidities has become increasingly significant.

ObjectivesTo evaluate cognitive and mood changes 3 months after shunting for idiopathic normal-pressure hydrocephalus (iNPH), and compare postoperative outcomes with matched healthy controls across cognitive domains.MethodsThirty-three iNPH patients underwent neuropsychological testing preoperatively and at 3 months; 71 age-, sex-, and education-matched controls were assessed once. Tests were grouped into six cognitive domains.ResultsShunting yielded significant gains in Verbal Memory and Psychomotor Pace; Executive Functions improved selectively. Non-Verbal Memory, Language, and Visuospatial Abilities showed no postoperative change. Depressive symptoms decreased significantly. However, at 3 months patients still performed worse than controls on all tests (all p < 0.001).ConclusionShunt surgery produces measurable yet domain-limited cognitive benefits in iNPH at 3 months, particularly in verbal learning and processing speed, alongside mood improvement. Performance remains below healthy norms, indicating partial recovery. Larger, prospective cohorts and longer follow-up are needed to determine durability, breadth of cognitive change, and predictors of response.

Lumbar puncture (LP) is a key diagnostic and therapeutic tool, yet concerns persist about its potential to induce brain herniation, especially in patients with elevated intracranial pressure (ICP). Despite ongoing debate, precise risk factors and pathophysiological mechanisms remain unclear. This systematic review aims to examine the risk of cerebellar and paradoxical brain herniation following LP, evaluate the current evidence regarding its incidence, and discuss the implications for clinical practice as well as show the gaps in research. Following PRISMA guidelines, a systematic literature review was conducted using the PubMed (MEDLINE) database. Studies from 1990 to 2024 focusing on bacterial meningitis, idiopathic intracranial hypertension, post-surgical states, and other conditions associated with elevated ICP were included. LP-related herniation was reported in diverse clinical settings, with cerebellar herniation primarily seen in bacterial meningitis and idiopathic intracranial hypertension. Herniation onset varied from minutes to days post-LP. While cranial CT is widely used for risk assessment, its predictive accuracy is debated. Although LP is relatively safe, herniation risk is highly context-dependent. Clinicians should integrate clinical, radiological, and pathophysiological factors in decision-making. Further research is needed to refine predictive models and establish evidence-based guidelines for high-risk patients.

Idiopathic intracranial hypertension (IIH) in children is a rare but vision-threatening condition characterized by elevated intracranial pressure (ICP) without an identifiable cause. While medical therapy remains the first-line approach, a subset of pediatric patients remains refractory, necessitating surgical or endovascular interventions. Venous sinus stenting (VSS) has emerged as a promising, minimally invasive alternative to cerebrospinal fluid (CSF) shunting, but its safety and efficacy in pediatric populations are not well-defined. A systematic literature review was conducted following PRISMA guidelines, focusing on pediatric patients (< 18 years) with medically refractory IIH treated with VSS. Databases searched included PubMed, ScienceDirect, Cochrane Library, and others, including studies published from January 1990 to September 2025. Data on patient selection, procedural outcomes, complications, and antiplatelet protocols were extracted and analyzed. Only studies rated ≥ 6 stars on the Newcastle–Ottawa Scale were included. Six primary studies were identified, reporting outcomes in 36 pediatric patients (mean age 13.32 ± 1.25 years). VSS led to marked improvement in headache (87.5

BACKGROUND AND PURPOSE:White matter changes assessed by DTI typically reflect tract functionality. This study aimed to investigate DTI parameter alterations in important regions pre- and postshunt implantation in patients with idiopathic normal pressure hydrocephalus (iNPH), alongside assessing the relationship between DTI parameters and clinical improvement. MATERIALS AND METHODS:Patients with probable iNPH underwent prospective preoperative MRI and comprehensive clinical work-up between 2017-2022. Patients with clinical symptoms of iNPH, positive result on a lumbar infusion test, and/or gait improvement after 120-hour lumbar drainage were diagnosed with iNPH and underwent shunt-placement surgery. Fractional anisotropy and mean diffusivity values for individual regions of interest were extracted from preoperative and postoperative MRI. These values were correlated with the clinical picture of individual patients. RESULTS:A total of 32 patients (73.59 ± 4.59 years) with definite iNPH were analyzed. Preoperative DTI characteristics of internal capsule and corona radiata correlated with the 1-year improvement in the Dutch Gait Scale postoperatively (all P < .036). Cognitive domain improvement after surgery in memory and psychomotor speed correlated with preoperative DTI values of cingulate gyrus (P = .050), uncinate fasciculus (P = .029), superior longitudinal fasciculus (P = .020), or corpus callosum (P < .045). CONCLUSIONS:DTI characteristics of white matter regions reflect clinical improvement after shunt surgery in patients with iNPH. They tend to improve toward physiologic DTI values, thus further accentuating the benefit of shunt surgery in both clinical and radiologic pictures.

Spinal cord injury (SCI) often results in irreversible sensorimotor and autonomic dysfunction, severely limiting independence and quality of life. Individuals with clinically complete SCI (AIS A) have traditionally been considered beyond functional recovery. This pilot study aimed to evaluate the therapeutic potential and broader impact of epidural spinal cord stimulation (eSCS) on this population. Three participants with chronic, sensorimotor complete thoracic SCI received implantation of a 32-contact epidural stimulator targeting the lumbosacral spinal cord. Personalized stimulation protocols were developed to support lower limb activation and upright posture. Motor, autonomic, and quality of life outcomes were assessed over a 12-month follow-up. All participants achieved independent standing through eSCS-enabled muscle activation, despite the absence of voluntary movement. The intervention led to improvements in postural control and trunk stability, as well as clinically meaningful gains in autonomic functions, including bladder, bowel, and sexual health, alongside reductions in spasticity and neuropathic pain. Importantly, participants reported sustained and substantial improvements in their perceived quality of life. This study provides evidence that eSCS can restore key functional capacities and significantly enhance the quality of life for individuals with sensorimotor complete SCI.

Disclosure: L. Kolatorova: None. T. Skodova: None. J. Vitku: None. M. Hill: None. P. Skalicky: None. O. Bradac: None. Background: Normal pressure hydrocephalus (NPH) is neurodegenerative disease manifested by balance impairment, urinary incontinence and dementia development, which can easily be mistaken for Alzheimer's or Parkinson's disease. The commonly used treatment is implantation of a ventriculoperitoneal shunt leading to a clinical improvement in 70–90% of patients, in contrast to other poorly treatable neurodegenerative disorder. Nervous system is an important target and source of steroids. In neurodegenerative disorders, the steroid metabolic pathways and transport channels in the nervous system may be disrupted, these changes are most likely to be reflected in the cerebrospinal fluid (CSF). All major steroid classes were considered to be active within the nervous system and those are termed neuroactive steroids (NAS). Several NAS (dehydroepiandrosterone (DHEA), pregnenolone, progesterone and their metabolites) are known to be synthesized directly in the brain, while others (androgens, corticoids etc.) are of peripheral origin. The aim of our study is to find CSF steroids that could be helpful in differential diagnosis of NPH. Methods: Three newly developed, highly sensitive LC-MS/MS methods for quantifying 17 NAS including androgens, gestagens, corticoids and estrogens were developed and validated. The methods can quantify NAS within order of pg/mL units. Results: First, we compared CSF samples from men (n=20) and woman (n=18) obtained within the NPH diagnostics. We found significantly elevated levels of testosterone and 17-hydroxyprogesterone in men. Second, we make a pilot study observing NPH patients (n=11) before, 3 and 12 months after the shunt implantation. We found significantly increased CSF levels of 7-ketoDHEA after 3 months, after 1year, the levels dropped back. The opposite results were found for estrone. The CSF 17-hydroxypregnenolone levels were significantly increased after 3 months and remained stable after 1 year. CSF 11-hydroxytestosterone increased after 3 months and its increase was also significant after 1 year. Surprising results were found for corticoids. Cortisol, cortisone, corticosterone and 11-deoxycortisol increased significantly 3 and 12 months after surgery. Conclusion: In accordance with our previous research, we found increased levels of neuroprotective 7-ketoDHEA. To the best of our knowledge, we have quantified for the first time the CSF levels of 17-hydroxypregnenolone, which were significantly increased in the 3- and 12-months follow-up. The increase was found also in 11-hydroxytestosterone, which metabolism within the nervous system is actually not fully understood. Until 2026, we plan to quantify the spectrum of NAS in CSF and plasma in much larger cohort of NPH patients as well as controls, and contribute to advancing the diagnosis and pathophysiology of NPH.Acknowledgement: Supported by NU23-04-00551 of Czech Ministry of Health. Presentation: Sunday, July 13, 2025

The increasing availability of advanced neuroimaging has led to a rise in incidental findings among pediatric patients. Management strategies include immediate surgical intervention, observation or surgery upon progression. These are influenced by imaging characteristics, lesion behavior over time, patient/family preferences, and the lesion's surgical risks. The thalamus's eloquent location often warrants a more conservative approach. Identifying features predictive of growth could help inform clinical decisions regarding surveillance and potential intervention. We retrospectively analyzed 44 pediatric patients with 46 thalamic incidentalomas, assessing radiological characteristics, temporal changes, and factors predictive of progression. Progression was defined as a change in size and/or new/increased contrast enhancement. Prognostic factors for progression (demographics, initial tumor volume, extension beyond thalamus, changes in enhancement, margin characteristics) were assessed for significance. Of 46 incidentalomas, 40 were followed longitudinally. Nine incidentalomas (22.5%) showed regression, while nine (22.5%) progressed. The average time to regression was 947 days, and to progression, 516 days. Three patients underwent biopsy due to progressive changes; each was diagnosed with low-grade glioma. Statistical analysis revealed that initial incidentaloma volume, extension beyond the thalamus, and contrast enhancement were significantly associated with progression (p = 0.025, p < 0.001, and p = 0.001, respectively). Most pediatric thalamic incidentalomas are small, stable, and likely low-grade. However, approximately one-fifth exhibit progressive features, warranting prolonged surveillance. Larger initial volume, extra-thalamic extension, and contrast enhancement are significant predictors of progression and may justify earlier intervention. Individualized management remains essential, balancing natural history with surgical risk.

PURPOSE:The specifics of biological behavior, anatomical localization, treatment, decision-making, and long-term prognosis in neonatal and infantile intracranial tumors have not been well studied. METHODS:A retrospective monocentric study of patients aged ≤ 12 months treated for an intracranial tumor over a 23-year period was performed. Data regarding the survival rate according to the tumor histology were evaluated in further detail. RESULTS:A total of 63 patients with a median age of 200 days at the first admission (interquartile range (IQR) = 118-301 days) were analyzed. Most tumors were supratentorial (67.7%). Overall survival according to histopathological subgroups of included tumors was the most favorable in the low-grade glioma subgroup with 1- and 3-year survival of 96% (95% confidence interval [CI] = 88.6-100%) and 88% (95% CI = 76.1-100%), while the 3-year survival for the embryonal tumors subgroup was 15% (95% CI = 4.2-53.4%). Mortality in the cohort reached 42.8% with the median time to death of 6 months (IQR = 1-12 months). CONCLUSION:Infantile and neonatal primary CNS tumors significantly vary from CNS tumors in older pediatric patients both in their localization, distribution of histopathological subtypes, and the presence of mutations specific to these tumors, providing useful therapeutic targets. Brain tumors in children under 1 year of age are scarce compared to other pediatric brain tumors.

The metabolic processes within the brain are reflected in the cerebrospinal fluid (CSF). It is in close contact with the nervous system, which is both target and source of multiple steroids. The aim of our study was to develop and validate robust, sensitive LC-MS/MS methods with and without derivatization step for the analysis of unconjugated steroids from all major steroid classes in CSF. The validation of the method without derivatization was performed for ten C19- steroids (dehydroepiandrosterone (DHEA), 7α-hydroxyDHEA, 7β-hydroxyDHEA, 7-ketoDHEA, testosterone, epitestosterone, dihydrotestosterone, 11-hydroxytestosterone, 11-ketotestosterone and androstenedione), ten C21- steroids (cortisol, 11-deoxycortisol, 21-deoxycortisol, cortisone, corticosterone, 11-deoxycorticosterone, pregnenolone, progesterone, 17-hydroxyprogesterone, aldosterone) and three C18- steroids (estrone, estradiol, estriol). The method with derivatization is validated for determination of eleven C19- steroids (testosterone, 11-ketodihydrotestosterone, 11-hydroxytestosterone, DHEA, 7α-hydroxyDHEA, 7β-hydroxyDHEA, 7-ketoDHEA, androstenedione, androsterone, epiandrosterone, 7β-hydroxyepiandrosterone) and six C21- steroids (cortisol, cortisone, corticosterone, pregnenolone, 17-hydroxypregnenolone, progesterone) in CSF. The method without derivatization is applicable for the determination of the majority of steroids in CSF, except for pregnenolone, 17-hydroxypregnenolone and DHEA, for which the derivatization method provides better sensitivity. When analyzing CSF samples of normal pressure hydrocephalus (NPH) patients, 11-ketodihydrotestosterone, epitestosterone, androsterone, epiandrosterone, 7β-hydroxyepiandrosterone, 7-ketoDHEA and 21-deoxycortisol were found to be below the LLOQ, suggesting that their presence is very limited. 17-hydroxypregnenolone, and 11-deoxycortisol were quantified for the first time, their CSF levels in NPH subjects are presented. We also observed significantly increased CSF levels of testosterone and 17-hydroxyprogesterone in men compared to women, both with NPH.

The lumbar infusion test (LIT) is a routine part of the diagnostic process of various CSF dynamics disorders in adults. However, it is rarely used in the paediatric population due to a lack of evidence substantiating its efficacy and overall indications. Articles utilizing the LIT in a paediatric cohort (≤ 18 years) were included according to the PRISMA guidelines with the Newcastle-Ottawa Scale to assess the risk of bias. This review was registered at PROSPERO database under number: CRD42024625857. A total of 15 studies, yielding 441 patients, were included in the review. The most common indications for LIT were to predict shunt responsiveness in hydrocephalus and idiopathic intracranial hypertension (IIH). In IIH, the interaction between cerebrospinal fluid pressure (CSFp) and sagittal sinus pressure (SSp) may offer valuable diagnostic insights and present a novel assessment approach. The LIT is a validated tool, especially effective for predicting shunt responsiveness and detecting malfunctions in both IIH and hydrocephalus. Data surrounding LIT usage in children is lacking and most studies are outdated. Caution is needed when interpreting resistance to outflow (Rout) due to potential overestimation, with more attention directed to CSFp and the pressure within the venous system coupling in IIH. Future studies should focus on standardizing LIT protocols across age groups with focusing more on signal characteristics rather than individual parameters and fostering interdisciplinary collaboration to optimize diagnostic accuracy.

Introduction: Pediatric low-grade gliomas arising from the thalamus or thalamopeduncular junction are rare. Prognostic factors are thus seldom reported in the literature. Research question: This systematic review aims to define the factors influencing the prognosis of pediatric patients with thalamic and thalamopeduncular low-grade gliomas. Material and methods: An extensive literature search in adherence to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed and included Web of Science, Scopus, and OVID interface (Medline and Embase). Original articles were selected if they provided data on 10 or more patients under 18 years old with separate or retrievable data for thalamic or thalamopeduncular low-grade gliomas, as well as at least one prognostic factor and its corresponding outcome. The risk of bias and applicability were assessed using The Quality Assessment of Prognostic Accuracy Studies criteria. Results: The study selection process resulted in the inclusion of 14 articles out of the initial pool of 876 references. These 14 articles encompassed data from 446 patients. The prognostic factors reported were the extent of resection in ten studies, age and radiotherapy in four studies, bilateral involvement and molecular genetics in two studies, and sex and dissemination in one study each. Significant prognostic factors included the extent of resection, bilateral involvement, histology, and radiotherapy. Discussion and conclusion: The reported factors considered significant for prognosis align with previously published data. The maximal safe resection, as a potentially curative modality for thalamic low-grade glioma, and the multidisciplinary approach to each patient should be a standard of care. Given the excellent long-term outlook of these patients, the extent of resection should not be pursued at the risk of neurological function since additional therapeutic possibilities are available today, such as molecular-targeted agents.

Brain arteriovenous malformations (AVMs) are a rare entity of vascular anomalies, characteristic of anatomical shunting where arterial blood directly flows into the venous circulation. The main aim of the active treatment policy of brain AVMs is the prevention of haemorrhage. There are well-established treatment strategies that continually improve in their safety and efficacy, primarily due to the advances in imaging modalities, targeted and novel techniques, the development of alternative treatment approaches, and even better experience with the disease itself. There are interesting imaging novelties that may be prospectively applicable in the decision-making and planning of the most effective treatment approach for individual patients with intracranial AVM. Surgery is often considered the first-line treatment; however, each patient should be evaluated individually, and the risks of the active treatment policy should not overcome the benefits of the spontaneous natural history of the disease. All treatment modalities, i.e., surgery, radiosurgery, endovascular embolization, and observation, are justified but need to be meticulously selected for each individual patient in order to deliver the best treatment outcome. This chapter deals with historical and currently applied dogmas, followed by introductions of advances in each available treatment modality of AVM management.

Phase contrast magnetic resonance imaging (PC-MRI) represents an opportunity to non-invasively investigate cerebral spinal fluid (CSF) flow in patients with idiopathic normal pressure hydrocephalus (iNPH). Studies in recent years have explored the diagnostic and prognostic value of PC-MRI derived parameters. This review aims to identify all PC-MRI studies of iNPH published since 2010, synthesise a review based on collated results, and analyse specific flow parameters identified in the selected studies. Our protocol was prospectively registered on PROSPERO [CRD42020180826]. We systematically searched four databases: Pubmed, Web of Science, Ovid, and Cochrane library to identify all eligible studies. Quality assessment was performed using a modified Newcastle–Ottawa Scale [19]. Systematic review was conducted according to Prisma guidelines. A random-effects model was used to perform meta-analysis on the available flow parameters. Eighteen records were identified for inclusion. Five studies were eligible for meta-analysis, representing 107 iNPH patients and 82 controls. CSF flow parameters available for analysis were stroke volume and peak velocity. Both were significantly higher than controls (p = 0.0007 and p = 0.0045 respectively) according to our random-effects analysis, consistent with a model of hyper-dynamic CSF in iNPH. Our systematic review revealed average stroke volumes in iNPH ranging from 43uL to over 200uL. Peak velocity values ranged from 5.9 cm/s to 12.8 cm/s. Significant increases in stroke volume and peak velocity values in iNPH patients suggest a place for PC-MRI as supplementary evidence in the diagnostic work-up of iNPH. Although shunting reduces aqueductal stroke volume and peak velocity, the ability of pre-shunt values to reliably predict treatment response remains complicated. We suggest that it may be more appropriate to consider a range of values that reflect varying probabilities of shunt success. We recommend that future studies should prioritise standardising PC-MRI protocols, and before then PC-MRI findings should be considered supportive rather than determinative.