Search Results (32)

Background: Intracranial pressure (ICP) monitoring is crucial in managing acute brain injury (ABI) to prevent secondary brain injury. While invasive techniques remain the gold standard, they can carry notable risks, such as infection and hemorrhage. Non-invasive techniques are increasingly used, but their inter-modality correlation and concordance have not been systematically evaluated. This study aimed to assess the correlation and concordance among four commonly used non-invasive neuromonitoring tools in patients with ABI undergoing invasive ICP monitoring. Methods: This was a secondary analysis of prospectively collected data from 100 adult patients admitted to the intensive care unit with traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), or intracerebral hemorrhage (ICH) who underwent invasive ICP monitoring. Simultaneous assessments using optic nerve sheath diameter (ONSD), transcranial Doppler-derived pulsatility index (PI), estimated ICP (eICP), and the neurological pupil index (NPi) were performed. Correlation between modalities was assessed using Spearman’s correlation coefficient (ρ), and concordance was evaluated with Cohen’s kappa coefficient (k). Results: We found weak correlations between ONSD and PI (ρ = 0.29), ONSD and NPi (ρ = −0.33), and PI and NPi (ρ = −0.33); moderate correlations between ONSD and eICP (ρ = 0.54) and PI and eICP (ρ = 0.48); and a strong inverse correlation between eICP and NPi (ρ = −0.71; all p < 0.05). Concordance was generally low, with the highest agreement between PI and eICP (k = 0.69). Most other tool pairings showed poor-to-fair concordance (k ≤ 0.30). Conclusions: Non-invasive neuromonitoring tools show variable correlation and limited agreement, suggesting they are not interchangeable. Each modality captures different aspects of cerebral physiology, supporting the use of a multimodal approach to improve accuracy in ICP estimation. Full article

Background and Objectives: In coronary artery bypass grafting (CABG) surgeries, monitoring intracranial pressure (ICP) is crucial due to neurological risks. Although pulsatile flow (PF) during cardiopulmonary bypass (CPB) is considered more physiological than non-pulsatile flow (NPF), its impact on ICP remains unclear. This study aimed to compare preoperative and postoperative optic nerve sheath diameter (ONSD) measurements between PF and NPF techniques to evaluate their effect on ICP changes. Materials and Methods: Sixty patients undergoing elective CABG (aged 45–75 years, ASA II-III-IV) were enrolled and divided into two groups depending on the cardiopulmonary bypass technique determined by the surgeon: PF (Group P, n = 30) and NPF (Group NP, n = 30). ONSD measurements were performed with ultrasound before surgery (Tpreop) and after surgery (Tpostop). Hemodynamic parameters and jugular and carotid vessel diameters were also recorded. Statistical analysis included t-tests, Mann–Whitney U-tests, chi-square tests, and Pearson correlation. Results: Both groups demonstrated significant increases in ONSD postoperatively compared to preoperative values (p < 0.001). However, no statistically significant difference in the magnitude of ONSD change was observed between the PF and NPF groups (p > 0.05). Group P showed lower ejection fractions and higher total inotrope requirements compared to Group NP (p < 0.01), but these factors did not translate into differences in postoperative ICP dynamics. Conclusions: ONSD measurements increased significantly after CABG surgery, regardless of perfusion type. PF and NPF strategies were comparable in terms of their effects on ICP as reflected by ONSD changes. ONSD ultrasonography appears to be a simple, rapid, and non-invasive tool for perioperative ICP monitoring in cardiac surgery. Further studies are needed to confirm these findings with dynamic intraoperative monitoring and neurocognitive assessments. Full article

Background/Objectives: Cerebrovascular events (CVEs) are a leading cause of intensive care unit (ICU) admissions from the emergency department, often associated with high morbidity and mortality rates. Identifying reliable, non-invasive predictors of mortality in these patients is critical for improving prognostic accuracy and guiding therapeutic strategies. This retrospective cohort study evaluates the predictive value of the optic nerve sheath diameter (ONSD), measured using magnetic resonance imaging (MRI), in determining mortality among ICU patients with CVEs. Methods: This single-center, retrospective observational study included 102 patients diagnosed with CVEs and admitted to the ICU at Gaziantep City Hospital between October 2023 and March 2024. This study adhered to the Declaration of Helsinki. Ethics approval was obtained from Gaziantep Islam Science and Technology University (Decision No. 394.36.08), and the requirement for informed consent was waived due to the retrospective design. The sample size was determined using G-Power 3.1.9.4. Results: A statistically significant positive correlation was observed between the ONSD and mortality (p = 0.002). Patients with higher ONSD values demonstrated an increased mortality risk, underscoring the potential prognostic value of ONSD measurements in this population. Conclusions: MRI-based ONSD measurement offers a non-invasive method for predicting mortality in ICU patients with CVEs. Its integration into routine diagnostic protocols could enhance clinical decision-making and patient outcomes. Further multicenter studies are warranted to validate these findings and standardize ONSD measurement techniques. Full article

Neuro-ophthalmological changes have been reported after prolonged exposure to microgravity; however, the pathophysiology remains unclear. Furthermore, several countermeasures have been suggested to counteract the side effects of microgravity. The objectives of the present study were twofold: (1) to assess the neuro-ophthalmological impact of 60 days of head-down bed rest (HDBR) and (2) to determine the potential effects of an antioxidant cocktail. In this case, 20 healthy male subjects completed a 60-day HDBR and were randomly allocated into two groups: a control condition without an antioxidant cocktail (CON) and a condition with an antioxidant cocktail (NUT). The retinal nerve fibre layer thickness (RNFLT) and central retinal thickness (CRT) were assessed with spectral domain optical coherence tomography. The optic nerve sheath diameter (ONSD) was measured by ocular ultrasonography and used to assess indirect changes in the intracranial pressure (ICP). The intraocular pressure (IOP) was assessed by Goldmann applanation tonometry. The CRT tended to be reduced after HDBR. The ONSD was increased at the end and after HDBR. The IOP tended to decrease after HDBR. Finally, the antioxidant cocktail had minor impacts on the ophthalmological changes induced by HDBR. It is worth noting that two participants presented peripapillary edema. Full article

Background/Objective: Orbital diseases often require precise measurements of eyeball volume, optic nerve sheath diameter (ONSD), and apex-to-eyeball distance (AED) for accurate diagnosis and treatment planning. This study aims to automate and optimize these measurements using advanced deep learning segmentation techniques on orbital Computed Tomography (CT) scans. Methods: Orbital CT datasets from individuals of various age groups and genders were used, with annotated masks for the eyeball and optic nerve. A 2D attention U-Net architecture was employed for segmentation, enhanced with slice-level information embeddings to improve contextual understanding. After segmentation, the relevant metrics were calculated from the segmented structures and evaluated for clinical applicability. Results: The segmentation model demonstrated varying performance across orbital structures, achieving a Dice score of 0.8466 for the eyeball and 0.6387 for the optic nerve. Consequently, eyeball-related metrics, such as eyeball volume, exhibited high accuracy, with a root mean square error (RMSE) of 1.28–1.90 cm³ and a mean absolute percentage error (MAPE) of 12–21% across different genders and age groups. In contrast, the lower accuracy of optic nerve segmentation led to less reliable measurements of optic nerve sheath diameter (ONSD) and apex-to-eyeball distance (AED). Additionally, the study analyzed the automatically calculated measurements from various perspectives, revealing key insights and areas for improvement. Conclusions: Despite these challenges, the study highlights the potential of deep learning-based segmentation to automate the assessment of ocular structures, particularly in measuring eyeball volume, while leaving room for further improvement in optic nerve analysis. Full article

The optic nerve sheath diameter (ONSD) can predict intracranial pressure and outcomes in neurological disease, but it remains unclear whether a small ONSD can be accurately measured on routine CT images with a slice thickness of approximately 4–5 mm. We measured the ONSD and ONSD/eyeball transverse diameter (ETD) ratio on routine-slice (4 mm) and thin-slice (0.6–0.75 mm) brain CT images from initial scans of acute ischemic stroke (AIS) patients. ONSD-related variables, National Institutes of Health Stroke Scale (NIHSS) scores, and age were compared between good (modified Rankin Scale [mRS] ≤ 2) and poor (mRS > 2) outcomes at discharge. Among 155 patients, 38 had poor outcomes. The thin-slice ONSD was different between outcome groups (p = 0.047), while the routine-slice ONSD showed no difference. The area under the curve (AUC) values for the ONSD and ONSD/ETD were 0.58 (95% CI, 0.49–0.66) and 0.58 (95% CI, 0.50–0.66) on the routine-slice CT, and 0.60 (95% CI, 0.52–0.68) and 0.62 (95% CI, 0.54–0.69) on the thin-slice CT. The thin-slice ONSD/ETD ratio correlated with initial NIHSS scores (r = 0.225, p = 0.005). After adjusting for NIHSS scores and age, ONSD-related variables were not associated with outcomes, and adding them to a model with NIHSS scores and age did not improve performance (all p-values > 0.05). Although ONSD measurements were not an independent outcome predictor, they correlated with stroke severity, and the thin-slice ONSD provided a slightly better prognostic performance than the routine-slice ONSD. Full article

Background: The objective of this investigation was to formulate a model for predicting intracranial pressure (ICP) by utilizing optic nerve sheath diameter (ONSD) during endovascular treatment for an aneurysmal subarachnoid hemorrhage (aSAH), incorporating explainable predictive modeling. Methods: ONSD measurements were conducted using a handheld ultrasonography device during the course of endovascular treatment (n = 126, mean age 58.82 ± 14.86 years, and female ratio 67.46%). The optimal ONSD threshold associated with an increased ICP was determined. Additionally, the association between ONSD and ICP was validated through the application of a linear regression machine learning model. The correlation between ICP and various factors was explored through the modeling. Results: With an ICP threshold set at 20 cmH₂O, 82 patients manifested an increased ICP, with a corresponding ONSD of 0.545 ± 0.08 cm. Similarly, with an ICP threshold set at 25 cmH₂O, 44 patients demonstrated an increased ICP, with a cutoff ONSD of 0.553 cm. Conclusions: We revealed a robust correlation between ICP and ONSD. ONSD exhibited a significant association and demonstrated potential as a predictor of ICP in patients with an ICP ≥ 25 cmH₂O. The findings suggest its potential as a valuable index in clinical practice, proposing a reference value of ONSD for increased ICP in the institution. Full article

In addition to general anesthesia and mechanical ventilation, robotic-assisted laparoscopic radical prostatectomy (RALP) necessitates maintaining a capnoperitoneum and placing the patient in a pronounced downward tilt (Trendelenburg position). While the effects of the resulting fluid shift on the cardiovascular system seem to be modest and well tolerated, the effects on the brain and the blood–brain barrier have not been thoroughly investigated. Previous studies indicated that select patients showed an increase in the optic nerve sheath diameter (ONSD), detected by ultrasound during RALP, which suggests an elevation in intracranial pressure. We hypothesize that the intraoperative fluid shift results in endothelial dysfunction and reduced cerebral clearance, potentially leading to transient neuronal damage. This prospective, monocentric, non-randomized, controlled clinical trial will compare RALP to conventional open radical prostatectomy (control group) in a total of 50 subjects. The primary endpoint will be the perioperative concentration of neurofilament light chain (NfL) in blood using single-molecule array (SiMoA) as a measure for neuronal damage. As secondary endpoints, various other markers for endothelial function, inflammation, and neuronal damage as well as the ONSD will be assessed. Perioperative stress will be evaluated by questionnaires and stress hormone levels in saliva samples. Furthermore, the subjects will participate in functional tests to evaluate neurocognitive function. Each subject will be followed up until discharge. Conclusion: This trial aims to expand current knowledge as well as to develop strategies for improved monitoring and higher safety of patients undergoing RALP. The trial was registered with the German Clinical Trials Register DRKS00031041 on 11 January 2023. Full article

Introduction: Traumatic brain injury (TBI) is one of the most common causes of death and an important burden to the worldwide healthcare system and society. There is a lack of guidelines for types of monitoring or neuroprotective therapy. The aim of this pilot study was to assess its feasibility and, furthermore, to evaluate the impact of Cerebrolysin on the following clinical outcomes: length of stay, Glasgow Outcome Scale (GOS) and mortality. Methods: A cohort of 56 patients was included in this non-randomised, real-time, pre–post-interventional study. The patients were assessed with the Glasgow Coma Scale (GCS) and divided into two groups: severe (GCS < 8) and non-severe (GCS > 8). After the radiological examination (CT scan), the patients were qualified for an immediate neurosurgical procedure if needed. The patients were admitted to the intensive care unit, where a standardised protocol for TBI treatment was implemented. Additional neuromonitoring was applied. Results: There were 56 patients (19 females; 33.9%), of which 41 were considered severe cases; the patients were allocated to the Cerebrolysin (n = 25) or control groups (n = 31). In a generalised linear model (GLM) approach, the use of Cerebrolysin was associated with a decrease in the probability of death in non-severe patients (by 0.333 (standard error (SE) = 0.157, p = 0.034)) but not in severe patients (estimate (Est.) = −0.115, SE = 0.127, p = 0.364). Patients who received Cerebrolysin and who were neuromonitored had favourable outcomes and better survival rates. Conclusions: A multimodal treatment approach with monitoring and Cerebrolysin may have a beneficial effect on patients with less severe TBIs; however, the present study has multiple limitations, and further research is needed. Full article

Background: To investigate whether ultrasound-based optic nerve sheath diameter (US-ONSD) is a reliable measure to follow up children with idiopathic intracranial hypertension (IIH). In addition, to analyze the inter- and intra-individual relationships between US-ONSD and intracranial pressure (ICP), and to investigate whether an individualized mathematical regression equation obtained from two paired US-ONSD/ICP values can be used to approximate ICP from US-ONSD values. Methods: 159 US examinations and 53 invasive ICP measures via lumbar puncture (LP) were performed in 28 children with IIH. US-ONSD was measured using a 12 Mhz linear transducer and compared to ICP values. In 15 children, a minimum of 2 paired US-ONSD/ICP determinations were performed, and repeated-measures correlation (rmcorr) and intra-individual correlations were analyzed. Results: The cohort correlation between US-ONSD and ICP was moderate (r = 0.504, p < 0.01). Rmcorr (r = 0.91, p < 0.01) and intra-individual correlations (r = 0.956–1) of US-ONSD and ICP were excellent. A mathematical regression equation can be calculated from two paired US-ONSD/ICP values and applied to the individual patient to approximate ICP from US-ONSD. Conclusions: Related to excellent intra-individual correlations between US-ONSD and ICP, an individualized regression formula, created from two pairs of US-ONSD/ICP values, may be used to directly approximate ICP based on US-ONSD values. Hence, US-ONSD may become a non-invasive and reliable measure to control treatment efficacy in pediatric IIH. Full article

Neuromonitoring is a critical tool for emergency rooms and intensive care units to promptly identify and treat brain injuries. The case report of a patient with status epilepticus necessitating orotracheal intubation and intravenous lorazepam administration is presented. A pattern of epileptiform activity was detected in the left temporal region, and intravenous Acyclovir was administered based on the diagnostic hypothesis of herpetic meningoencephalitis. The neurointensivist opted for multimodal non-invasive bedside neuromonitoring due to the complexity of the patient’s condition. A Brain4care (B4C) non-invasive intracranial compliance monitor was utilized alongside the assessment of an optic nerve sheath diameter (ONSD) and transcranial Doppler (TCD). Based on the collected data, a diagnosis of intracranial hypertension (ICH) was made and a treatment plan was developed. After the neurosurgery team’s evaluation, a stereotaxic biopsy of the temporal lesion revealed a grade 2 diffuse astrocytoma, and an urgent total resection was performed. Research suggests that monitoring patients in a dedicated neurologic intensive care unit (Neuro ICU) can lead to improved outcomes and shorter hospital stays. In addition to being useful for patients with a primary brain injury, neuromonitoring may also be advantageous for those at risk of cerebral hemodynamic impairment. Lastly, it is essential to note that neuromonitoring technologies are non-invasive, less expensive, safe, and bedside-accessible approaches with significant diagnostic and monitoring potential for patients at risk of brain abnormalities. Multimodal neuromonitoring is a vital tool in critical care units for the identification and management of acute brain trauma as well as for patients at risk of cerebral hemodynamic impairment. Full article

Ultrasonographic optic nerve sheath diameter (ONSD) measurement is an accurate, portable, and non-invasive method of detecting raised intracranial pressure that can also reflect dynamic, real-time changes in intracranial pressure fluctuations. Various studies have shown the mean range of ONSD to vary greatly across different population groups. This study aimed to determine the mean ONSD in healthy Black South African adults. In this cross-sectional study, healthy black South African adult participants underwent optic nerve sheath ultrasound of the right eye, with the diameter being measured at 3 mm behind the retina in two different planes. The average of the two measurements was used to find the mean optic nerve sheath diameter. This measurement was compared to that found in a Canadian adult population, and the effect of age, gender, and co-morbidities on ONSD was assessed. A total of 99 participants were included in this study, of which 39 were male and 60 were female. The mean ONSD was found to be 5.1 mm (SD ± 0.33). This value was significantly higher than the mean ONSD observed in the Canadian population (p < 0.001). There was no significant difference found between the mean ONSD in males and females (p = 0.652), and both age and presence of co-morbidities were not found to significantly correlate with ONSD. (p = 0.693 and p = 0.974, respectively). Full article

Background and Objectives: Supraglottic airway devices (SADs) are known to be useful in eliminating the drawbacks of laryngoscopy and tracheal intubation, especially ocular pressure and stress responses. The ultrasonographic measurement of optic nerve sheath diameter (ONSD) reflects increases in intracranial pressure (ICP). In our study, we aimed to compare the effects of SADs on hemodynamic response and ONSD. Materials and Methods: Our prospective study included 90 ASA I–II patients over the age of 18 who did not have a history of difficult intubation or ophthalmic pathology. The patients were randomly divided into three groups based on the laryngeal mask airway (LMA) devices used: ProSeal LMA (pLMA, n = 30), LMA Supreme (sLMA, n = 30), and I-gel (n = 30). The bilateral ONSD measurements and hemodynamic data of the patients who underwent standard anesthesia induction and monitoring were recorded before induction (T0) and 1 min (T1), 5 min (T5), and 10 min (T10) after SAD placement. Results: At all measurement times, the hemodynamic responses and ONSD values of the groups were similar. In all three groups, intergroup hemodynamic changes at T0 and T1 were similar and higher than those at other times of measurement (p < 0.001). The ONSD values of all groups increased at T1, and they tended to return to baseline values afterward (p < 0.001). Conclusions: We concluded that all three SADs could be used safely because they preserved both hemodynamic stability and ONSD changes in their placement processes, and they did not cause elevations in ONSD to an extent that would lead to increased ICP. Full article

Background: The measurement of optic nerve sheath diameter (ONSD) as a non-invasive method of estimating intracranial pressure has been widely reported in the literature. However, few studies have evaluated the accuracy of magnetic resonance imaging (MRI) in assessing ONSD measurements, although it is considered a very reliable method, it is not easily repeatable, expensive and is not readily available bedside. Herein, an assessment of the intra- and inter-rater reliability of ONSD assessment using MRI was conducted. Methods: A consecutive, prospective cohort of patients with suspected idiopathic normal-pressure hydrocephalus was analyzed. ONSD MRI measurements of the transverse and sagittal diameters at a distance of 3 mm behind the papilla were evaluated twice each by two expert neuroradiologists. The correlations between MRI examiners were calculated using the concordance correlation coefficient (CCC). Results: Fifty patients were included in the study. ONSD MRI average measurements were substantially higher than clinically expected (>5 mm). Considering intra-rater concordance, only one of the two neuroradiologists achieved an excellent score at CCC. Only a moderate inter-observer CCC for MRI assessment was found at all diameters. Conclusions: The use of a widespread MRI sequence (3D T1) to measure ONSD is not an accurate method since it may overestimate measurements and is dependent upon an operator. Full article

Background and Objectives: Cardiopulmonary bypass (CPB) is an extracorporeal circuit that provides surgical access to an immobile and bloodless area, allowing for technical and procedural advances in cardiothoracic surgery. CBP can alter the integrity of the blood–brain barrier and cause changes in intracranial pressure (ICP) postoperatively. Optical nerve sheath diameter (ONSD) measurement is among the alternative non-invasive methods for ICP monitoring. In this study, we aimed to evaluate the optic nerve sheath diameter measurements under the guidance of ultrasonography for ICP changes during the extracorporeal circulation process. Materials and Methods: The study population included 21 patients over 18 years of age who required extracorporeal circulation. Demographic data of the patients, such as age, gender, comorbidity, American Society of Anesthesiologists (ASA) classification and reason for operation (coronary artery disease or mitral or aortic valve disease) were recorded. The ONSD was measured and evaluated before the extracorporeal circulation (first time) and at the 30th minute (second time), 60th minute (third time) and 90th minute (fourth time) of the extracorporeal circulation. Non-invasive ICP (ICP ONSD) values were calculated based on the ONSD values found. Results: The mean ONSD values measured before the extracorporeal circulation of the patients were found to be 4.13 mm (3.8–4.6) for the right eye and 4.36 mm (4.1–4.7) for the left eye. Calculated nICPONSD values of 11.0 mm Hg (1.0–21.0) for the right eye and 10.89 mm Hg (1.0–21.0) for the left eye were found. It was observed that there was a significant increase in the ONSD and nlCPONSD values recorded during the extracorporeal circulation of all patients compared to the baseline values (p < 0.005). Conclusions: During extracorporeal circulation, ultrasound-guided ONSD measurement is an easy, inexpensive and low-complication method that can be performed at the bedside during the operation to monitor ICP changes. Full article