BACKGROUND: Decompressive hemicraniectomy (DHC) is used after severe brain damages with elevated, refractory intracranial pressure (ICP). In a non age-restricted population, mortality rates and long-term outcomes following DHC are still unclear. This study\'s objectives were to examine both, as well as to identify predictors of unfavourable outcomes.
METHODS: We undertook a retrospective observational analysis of patients aged 18 years and older who underwent DHC at the University Hospital of Bonn between 2018 and 2020, due to traumatic brain injury (TBI), haemorrhage, tumours or infections. Patient outcomes were assessed by conducting telephone interviews, utilising questionnaires for modified Rankin Scale (mRS) and extended Glasgow Outcome scale (GOSE). We evaluated the health-related quality of life using the EuroQol (EQ-5D-5L) scale.
RESULTS: A total of 144 patients with a median age of 58.5 years (range: 18 to 85 years) were evaluated. The mortality rate was 67%, with patients passing away at a median of 6.0 days (IQR [1.9-37.6]) after DHC. Favourable outcomes, as assessed by the mRS and GOSE were observed in 10.4% and 6.3% of patients, respectively. Cox regression analysis revealed a 2.0% increase in the mortality risk for every year of age (HR = 1.017; 95% CI [1.01-1.03]; p = 0.004). Uni- and bilateral fixed pupils were associated with a 1.72 (95% CI [1.03-2.87]; p = 0.037) and 3.97 (95% CI [2.44-6.46]; p < 0.001) times higher mortality risk, respectively. ROC-analysis demonstrated that age and pupillary reactivity predicted 6-month mortality with an AUC of 0.77 (95% CI [0.69-0.84]). The only parameter significantly associated with a better quality of life was younger age.
CONCLUSIONS: Following DHC, mortality remains substantial, and favourable outcomes occur rarely. Particularly in elderly patients and in the presence of clinical signs of herniation, mortality rates are notably elevated. Hence, the indication for DHC should be set critically.

OBJECTIVE: Reduced intracranial compliance (ICC) may be an important factor in the pathophysiology of Chiari malformation type I (CM-I). However, direct measurement of ICC is controversial because of its invasiveness, particularly in children. Instead, ICC may be estimated from continuous measurements of intracranial pressure (ICP), where the metric mean wave amplitude (MWA) has been found to be more useful as a surrogate marker of ICC than mean ICP. This observational study investigated the distribution of MWA and mean ICP in symptomatic children with CM-I, as well as their association with clinical and radiological findings.
METHODS: From a consecutive series of children treated for CM-I at a single institution between 2006 and 2023, the authors analyzed ICP scores in those who underwent an overnight preoperative ICP recording in which MWA was calculated. Clinical and radiological data were retrieved from the patient records.
RESULTS: Thirty-seven children (mean age 12.4 ± 3.6 years) with symptomatic CM-I were identified. From the overnight ICP measurements, the average MWA was 5.2 ± 1.3 mm Hg: 56% of children had an abnormal MWA (> 5 mm Hg) and 33% had a borderline MWA (4-5 mm Hg). In contrast, the average mean ICP was 9.7 ± 4.1 mm Hg: 8% of children had an abnormal mean ICP (> 15 mm Hg) and 41% had a borderline mean ICP (10-15 mm Hg). Thus, more children were found to have an abnormal MWA than an abnormal mean ICP (p < 0.001). MWA was significantly higher in the subgroup of children with medullary compression in the foramen magnum, as seen on MRI, than in those without (5.6 ± 1.0 mm Hg vs 4.7 ± 1.4 mm Hg, p = 0.03), whereas a similar difference was not observed for mean ICP (9.9 ± 4.6 mm Hg vs 9.7 ± 3.7 mm Hg, p = 0.889).
CONCLUSIONS: In this cohort of symptomatic children with CM-I, MWA was more frequently abnormal than mean ICP, with a clinically significant discrepancy in half of the patients. Moreover, MWA was significantly higher in patients with medullary compression. Based on these findings, the authors\' interpretation is that in children with CM-I, the ICC may be reduced, as indicated by increased MWA, even though the mean ICP is within normal thresholds.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is a complex neurological condition characterized by symptoms of increased intracranial pressure of unclear etiology. While transverse sinus stenosis (TSS) is often present in patients with IIH, how and why it occurs remains unclear.
METHODS: IIH patients and a set of age-matched normal controls were identified from our single-center tertiary care institution from 2016 to 2024. Brain MRIs before treatment were computationally segmented and parcellated using FreeSurfer software. Extent of TSS on MR venograms was graded using the Farb scoring system. Relationship between normalized brain volume, normalized brain-to-CSF volume, and TSS was investigated. Multiple linear regression was conducted to investigate the association between continuous variables, accounting for the covariates body mass index, sex, and age.
RESULTS: In total, 84 IIH patients (mean age, 29.8 years; 87% female) and 15 normal controls (mean age, 28.1 years) were included. Overall, increasing/worsening TSS was found to be significantly associated with normalized total brain volume (p=0.018, R=0.179) and brain-to-CSF ratio volume (p=0.026, R=0.184). Additionally, there was a significant difference between controls and IIH patients with mild and severe stenosis regarding normalized total brain volume (ANCOVA, p=0.023) and brain-to-CSF ratio volume (ANCOVA, p=0.034). Likewise, IIH patients with severe TSS had a significantly higher brain-to-CSF volume compared with controls (p=0.038) and compared with IIH patients with mild TSS (p=0.038).
CONCLUSIONS: These findings suggest that total brain volume is associated with extent of TSS, which may reflect extramural venous compression due to enlarged brain and/or venous hypertension with associated cerebral congestion/swelling.

Craniotomy or decompressive craniectomy are among the therapeutic options to prevent or treat secondary damage after severe brain injury. The choice of procedure depends, among other things, on the type and severity of the initial injury. It remains controversial whether both procedures influence the neurological outcome differently. Thus, estimating the risk of brain herniation and death and consequently potential organ donation remains difficult. All patients at the University Hospital Münster for whom an isolated craniotomy or decompressive craniectomy was performed as a treatment after severe brain injury between 2013 and 2022 were retrospectively included. Proportion of survivors and deceased were evaluated. Deceased were further analyzed regarding anticoagulants, comorbidities, type of brain injury, potential and utilized donation after brain death. 595 patients were identified, 296 patients survived, and 299 deceased. Proportion of decompressive craniectomy was higher than craniotomy in survivors (89% vs. 11%, p < 0.001). Brain death was diagnosed in 12 deceased and 10 donations were utilized. Utilized donations were comparable after both procedures (5% vs. 2%, p = 0.194). Preserved brain stem reflexes as a reason against donation did not differ between decompressive craniectomy or craniotomy (32% vs. 29%, p = 0.470). Patients with severe brain injury were more likely to survive after decompressive craniectomy than craniotomy. Among the deceased, potential and utilized donations did not differ between both procedures. This suggests that brain death can occur independent of the previous neurosurgical procedure and that organ donation should always be considered in end-of-life decisions for patients with a fatal prognosis.

Deep brain stimulation (DBS) has emerged as an important therapeutic option for several movement disorders; however, the management of acute complications, such as acute subdural hematoma (ASDH), remains challenging. This is the case of a 71-year-old woman with Parkinson\'s disease who developed ASDH 12 years after bilateral DBS placement. On admission with altered consciousness, imaging revealed significant displacement of the DBS electrodes because of the hematoma. Emergent craniotomy with endoscopic evacuation was performed with preservation of the DBS system. Postoperatively, complete evacuation of the hematoma was confirmed, and the patient experienced significant clinical improvement. ASDH causes significant electrode displacement in patients undergoing DBS. After hematoma evacuation, the electrodes were observed to return to their proper position, and the patient exhibited a favorable clinical response to stimulation. To preserve the DBS electrodes, endoscopic hematoma evacuation via a small craniotomy may be useful.

Even with the powerful statistical parameters derived from the Extreme Gradient Boost (XGB) algorithm, it would be advantageous to define the predicted accuracy to the level of a specific case, particularly when the model output is used to guide clinical decision-making. The probability density function (PDF) of the derived intracranial pressure predictions enables the computation of a definite integral around a point estimate, representing the event\'s probability within a range of values. Seven hold-out test cases used for the external validation of an XGB model underwent retinal vascular pulse and intracranial pressure measurement using modified photoplethysmography and lumbar puncture, respectively. The definite integral ±1 cm water from the median (DIICP) demonstrated a negative and highly significant correlation (-0.5213±0.17, p< 0.004) with the absolute difference between the measured and predicted median intracranial pressure (DiffICPmd). The concordance between the arterial and venous probability density functions was estimated using the two-sample Kolmogorov-Smirnov statistic, extending the distribution agreement across all data points. This parameter showed a statistically significant and positive correlation (0.4942±0.18, p< 0.001) with DiffICPmd. Two cautionary subset cases (Case 8 and Case 9), where disagreement was observed between measured and predicted intracranial pressure, were compared to the seven hold-out test cases. Arterial predictions from both cautionary subset cases converged on a uniform distribution in contrast to all other cases where distributions converged on either log-normal or closely related skewed distributions (gamma, logistic, beta). The mean±standard error of the arterial DIICP from cases 8 and 9 (3.83±0.56%) was lower compared to that of the hold-out test cases (14.14±1.07%) the between group difference was statistically significant (p<0.03). Although the sample size in this analysis was limited, these results support a dual and complementary analysis approach from independently derived retinal arterial and venous non-invasive intracranial pressure predictions. Results suggest that plotting the PDF and calculating the lower order moments, arterial DIICP, and the two sample Kolmogorov-Smirnov statistic may provide individualized predictive accuracy parameters.

Fat embolism syndrome is a common occurrence after orthopedic trauma and surgery. Cerebral fat embolism (CFE) may arise after fat globules enter the arterial circulation. The neurological manifestations of CFE vary and generally carries a favorable outcome. A small number of reports exist regarding patients with CFE who experienced severe neurological deficits and significant edema on radiographic studies, and subsequently underwent decompressive hemicraniectomy (DHC), some of which had full neurological recoveries. Here, we present the case of a 21-year-old male who presented after a motorcycle accident with multiple orthopedic injuries, who after fixation did not awake from anesthesia. The patient was ultimately found to have cerebral fat emboli, and developed significant edema and swelling. The patient underwent DHC with subsequent cranioplasty and returned to his neurological baseline seven months after his initial injury. DHC for CFE has been described in a few cases with some patients have had substantive recoveries, including the present case. This case emphasizes the importance of promptly recognizing and reversing elevated intracranial pressures and the possibility of promising recoveries.

BACKGROUND: Raised intracranial pressure (ICP) contributes to approximately 20% of the admissions in the paediatric intensive care unit (PICU) in our setting. Timely identification and treatment of raised ICP is important to prevent brain herniation and death in such cases. The objective of this study was to examine the role of optic nerve sheath diameter (ONSD) in detecting clinically relevant raised ICP in children.
METHODS: A hospital-based observational analytical study in a PICU of a tertiary care institute in India on children aged 2-14 years. ONSD was measured in all children on three time points that is, day 1, day 2 and between day 4 and 7 of admission. ONSD values were compared between children with and without clinical signs of raised ICP.
RESULTS: Out of 137 paediatric patients recruited, 34 had signs of raised ICP. Mean ONSD on day 1 was higher in children with signs of raised ICP (4.99±0.57 vs 4.06±0.40; p<0.01). Mean ONSD on day 2 also was higher in raised ICP patients (4.94±0.55 vs 4.04±0.40; p<0.01). The third reading between days 4 and 7 of admission was less than the first 2 values but still higher in raised ICP patients (4.48±1.26 vs 3.99±0.57; p<0.001). The cut-off ONSD value for detecting raised ICP was 4.46 mm on the ROC curve with an area under curve 0.906 (95% CI 0.844 to 0.968), 85.3% sensitivity and 86.4% specificity. There was no difference in ONSD between the right and the left eyes at any time point irrespective of signs of raised ICP.
CONCLUSIONS: We found that measurement of ONSD by transorbital ultrasound was able to detect clinically relevant raised ICP with an excellent discriminatory performance at the cut-off value of 4.46 mm.

Major advances in neurocritical care and the modalities used to treat aneurysms have led to improvement in the outlook of patients with aneurysmal subarachnoid hemorrhage. Yet, several knowledge gaps remain widely open. Variability in practices stems from the lack of solid evidence to guide management, which recent guidelines from professional organizations aim to mitigate. In this article, the authors review some of these gaps in knowledge, highlight important messages from recent management guidelines, emphasize aspects of our practice that we consider particularly useful to optimize patient outcomes, and suggest future areas of research.

UNASSIGNED: Patients with high-grade gliomas are at risk of developing increased intracranial hypertension (ICHT) in relation to the increase in volume of their tumor. ICP change cannot be measured by invasive method but can be estimated by using routine clinical signs, in combination with a standard imaging method, magnetic resonance imaging (MRI). A non-invasive monitoring of ICP could be of interest in high-grade glioma, in particular after radiotherapy treatment with as major side effect a cerebral oedema.
UNASSIGNED: This prospective clinical study aimed to compare the ICP changes (estimated by a non-invasive method based upon distortion product otoacoustic emissions (DPOAE) monitoring) with volume changes observed on MRI in patients with high-grade gliomas treated with radiotherapy. DPOAE measurements were performed one month after the end of radiotherapy and then every 3 months for one year. At each visit, the patient also underwent MRI as well as an evaluation of clinical signs.
UNASSIGNED: The variation in the estimate of intracranial pressure readout measured at each follow-up visit (in absolute value with respect to the baseline measurements) was significantly associated with the variation of T2/FLAIR volume (n=125; p<0.001) with a cut off value of change ICP readout of 40.2 degrees (e.i. an estimated change of 16 mm Hg).
UNASSIGNED: The GMaPIC trial confirm the hypothesis that the ICP change estimated by DPOAEs measurement using a non-invasive medical device is correlated with the change of the tumor or edema in high grade glioma after radiotherapy. The device could thus become an easy-to-use and non-invasive intracranial pressure monitoring tool for these patients.
UNASSIGNED: Clinicaltrials.gov, identifier (NCT02520492).